National Library of Energy BETA

Sample records for ignition system spark

  1. Low current extended duration spark ignition system

    DOE Patents [OSTI]

    Waters, Stephen Howard; Chan, Anthony Kok-Fai

    2005-08-30

    A system for firing a spark plug is disclosed. The system includes a timing controller configured to send a first timing signal and a second timing signal. The system also includes an ignition transformer having a primary winding and a secondary winding and a spark-plug that is operably associated with the secondary winding. A first switching element is disposed between the timing controller and the primary winding of the ignition transformer. The first switching element controls a supply of power to the primary winding based on the first timing signal. Also, a second switching element is disposed between the timing controller and the primary winding of the ignition transformer. The second switching element controls the supply of power to the primary winding based on the second timing signal. A method for firing a spark plug is also disclosed.

  2. Laser spark distribution and ignition system

    DOE Patents [OSTI]

    Woodruff, Steven (Morgantown, WV); McIntyre, Dustin L. (Morgantown, WV)

    2008-09-02

    A laser spark distribution and ignition system that reduces the high power optical requirements for use in a laser ignition and distribution system allowing for the use of optical fibers for delivering the low peak energy pumping pulses to a laser amplifier or laser oscillator. An optical distributor distributes and delivers optical pumping energy from an optical pumping source to multiple combustion chambers incorporating laser oscillators or laser amplifiers for inducing a laser spark within a combustion chamber. The optical distributor preferably includes a single rotating mirror or lens which deflects the optical pumping energy from the axis of rotation and into a plurality of distinct optical fibers each connected to a respective laser media or amplifier coupled to an associated combustion chamber. The laser spark generators preferably produce a high peak power laser spark, from a single low power pulse. The laser spark distribution and ignition system has application in natural gas fueled reciprocating engines, turbine combustors, explosives and laser induced breakdown spectroscopy diagnostic sensors.

  3. Laser Spark Distribution and Ignition System - Energy Innovation Portal

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Vehicles and Fuels Vehicles and Fuels Industrial Technologies Industrial Technologies Electricity Transmission Electricity Transmission Advanced Materials Advanced Materials Find More Like This Return to Search Laser Spark Distribution and Ignition System A method of creating sparks in lean fuel/air mixtures without expensive,short-lifetime spark plugs National Energy Technology Laboratory Contact NETL About This Technology Publications: PDF Document Publication Laser Spark Distribution and

  4. EBDI® - Application of a High BMEP Downsized Spark Ignited Engine |

    Office of Energy Efficiency and Renewable Energy (EERE) Indexed Site

    Department of Energy EBDI® - Application of a High BMEP Downsized Spark Ignited Engine EBDI® - Application of a High BMEP Downsized Spark Ignited Engine Application of a High BMEP Downsized Spark Ignited Engine PDF icon deer09_beazley.pdf More Documents & Publications Fuel-Induced System Responses The Role Unconventional Fuels May Play in Altering Exhaust Conditions from Conventional and Low Temperature Modes of Combustion Effect of Compression Ratio and Piston Geometry on RCCI load

  5. Simultaneous dual mode combustion engine operating on spark ignition and homogenous charge compression ignition

    DOE Patents [OSTI]

    Fiveland, Scott B.; Wiggers, Timothy E.

    2004-06-22

    An engine particularly suited to single speed operation environments, such as stationary power generators. The engine includes a plurality of combustion cylinders operable under homogenous charge compression ignition, and at least one combustion cylinder operable on spark ignition concepts. The cylinder operable on spark ignition concepts can be convertible to operate under homogenous charge compression ignition. The engine is started using the cylinders operable under spark ignition concepts.

  6. Fundamental Studies of Ignition Process in Large Natural Gas Engines Using Laser Spark Ignition

    SciTech Connect (OSTI)

    Azer Yalin; Bryan Willson

    2008-06-30

    Past research has shown that laser ignition provides a potential means to reduce emissions and improve engine efficiency of gas-fired engines to meet longer-term DOE ARES (Advanced Reciprocating Engine Systems) targets. Despite the potential advantages of laser ignition, the technology is not seeing practical or commercial use. A major impediment in this regard has been the 'open-path' beam delivery used in much of the past research. This mode of delivery is not considered industrially practical owing to safety factors, as well as susceptibility to vibrations, thermal effects etc. The overall goal of our project has been to develop technologies and approaches for practical laser ignition systems. To this end, we are pursuing fiber optically coupled laser ignition system and multiplexing methods for multiple cylinder engine operation. This report summarizes our progress in this regard. A partial summary of our progress includes: development of a figure of merit to guide fiber selection, identification of hollow-core fibers as a potential means of fiber delivery, demonstration of bench-top sparking through hollow-core fibers, single-cylinder engine operation with fiber delivered laser ignition, demonstration of bench-top multiplexing, dual-cylinder engine operation via multiplexed fiber delivered laser ignition, and sparking with fiber lasers. To the best of our knowledge, each of these accomplishments was a first.

  7. Special Feature: Energy - The Spark that Ignited DOE Supercomputing

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Energy - The Spark that Ignited DOE Supercomputing Special Feature: Energy - The Spark that Ignited DOE Supercomputing Scientific Computing for Energy Independence and a Clean Energy Future September 16, 2013 Contact: Linda Vu, lvu@lbl.gov, +1 510 495 2402 1280px-OREGONSODD-EVENPLANREDUCEDTHELINESATGASSTATIONSDURINGTHEFUELCRISISINTHEFALLANDWINTEROF1973-74....-NARA-555498.jpg Oregon's odd-even plan reduced the lines at gas stations during the fuel crisis in the fall and winter of 1973-74. This

  8. Improving the Efficiency of Spark Ignited, Stoichiometric Natural Gas

    Office of Energy Efficiency and Renewable Energy (EERE) Indexed Site

    Engines | Department of Energy Spark Ignited, Stoichiometric Natural Gas Engines Improving the Efficiency of Spark Ignited, Stoichiometric Natural Gas Engines This work focused on using camless engine technology to improve the efficiency of a natural gas engine. Late intake close timing and cylinder deactivation were utilized to meet a peak BTE > 40%. PDF icon p-09_giordano.pdf More Documents & Publications Advanced Natural Gas Reciprocating Engines (ARES) - Presentation by Cummins,

  9. Turbocharged Spark Ignited Direct Injection - A Fuel Economy Solution for

    Office of Energy Efficiency and Renewable Energy (EERE) Indexed Site

    The US | Department of Energy Turbocharged Spark Ignited Direct Injection - A Fuel Economy Solution for The US Turbocharged Spark Ignited Direct Injection - A Fuel Economy Solution for The US Turbocharged SIDI is the most promising advanced gasoline technology; combines existing & proven technologies in a synergistic manner, offers double digit fuel economy benefits, much lower cost than diesel or hybrid. PDF icon deer09_whitaker.pdf More Documents & Publications E85 Optimized Engine

  10. Ignition system monitoring assembly

    SciTech Connect (OSTI)

    Brushwood, John Samuel

    2003-11-04

    An ignition system monitoring assembly for use in a combustion engine is disclosed. The assembly includes an igniter having at least one positioning guide with at least one transmittal member being maintained in a preferred orientation by one of the positioning guides. The transmittal member is in optical communication with a corresponding target region, and optical information about the target region is conveyed to the reception member via the transmittal member. The device allows real-time observation of optical characteristics of the target region. The target region may be the spark gap between the igniter electrodes, or other predetermined locations in optical communication with the transmittal member. The reception member may send an output signal to a processing member which, in turn, may produce a response to the output signal.

  11. Burner ignition system

    DOE Patents [OSTI]

    Carignan, Forest J. (Bedford, MA)

    1986-01-21

    An electronic ignition system for a gas burner is battery operated. The battery voltage is applied through a DC-DC chopper to a step-up transformer to charge a capacitor which provides the ignition spark. The step-up transformer has a significant leakage reactance in order to limit current flow from the battery during initial charging of the capacitor. A tank circuit at the input of the transformer returns magnetizing current resulting from the leakage reactance to the primary in succeeding cycles. An SCR in the output circuit is gated through a voltage divider which senses current flow through a flame. Once the flame is sensed, further sparks are precluded. The same flame sensor enables a thermopile driven main valve actuating circuit. A safety valve in series with the main gas valve responds to a control pressure thermostatically applied through a diaphragm. The valve closes after a predetermined delay determined by a time delay orifice if the pilot gas is not ignited.

  12. Method for operating a spark-ignition, direct-injection internal combustion engine

    DOE Patents [OSTI]

    Narayanaswamy, Kushal; Koch, Calvin K.; Najt, Paul M.; Szekely, Jr., Gerald A.; Toner, Joel G.

    2015-06-02

    A spark-ignition, direct-injection internal combustion engine is coupled to an exhaust aftertreatment system including a three-way catalytic converter upstream of an NH3-SCR catalyst. A method for operating the engine includes operating the engine in a fuel cutoff mode and coincidentally executing a second fuel injection control scheme upon detecting an engine load that permits operation in the fuel cutoff mode.

  13. Spark ignited turbulent flame kernel growth. Annual report, January--December, 1992

    SciTech Connect (OSTI)

    Santavicca, D.A.

    1994-06-01

    Cyclic combustion variations in spark-ignition engines limit the use of dilute charge strategies for achieving low NO{sub x} emissions and improved fuel economy. Results from an experimental study of the effect of incomplete fuel-air mixing (ifam) on spark-ignited flame kernel growth in turbulent propane-air mixtures are presented. The experiments were conducted in a turbulent flow system that allows for independent variation of flow parameters, ignition system parameters, and the degree of fuel-air mixing. Measurements were made at 1 atm and 300 K conditions. Five cases were studied; a premixed and four incompletely mixed cases with 6%, 13%, 24% and 33% RMS (root-mean-square) fluctuations in the fuel/air equivalence ratio. High speed laser shadowgraphy at 4,000 frames-per-second was used to record flame kernel growth following spark ignition, from which the equivalent flame kernel radius as a function of time was determined. The effect of ifam was evaluated in terms of the flame kernel growth rate, cyclic variations in the flame kernel growth, and the rate of misfire. The results show that fluctuations in local mixture strength due to ifam cause the flame kernel surface to become wrinkled and distorted; and that the amount of wrinkling increases as the degree of ifam. Ifam was also found to result in a significant increase in cyclic variations in the flame kernel growth. The average flame kernel growth rates for the premixed and the incompletely mixed cases were found to be within the experimental uncertainty except for the 33%-RMS-fluctuation case where the growth rate is significantly lower. The premixed and 6%-RMS-fluctuation cases had a 0% misfire rate. The misfire rates were 1% and 2% for the 13%-RMS-fluctuation and 24%-RMS-fluctuation cases, respectively; however, it drastically increased to 23% in the 33%-RMS-fluctuation case.

  14. Extending lean operating limit and reducing emissions of methane spark-ignited engines using a microwave-assisted spark plug

    DOE Public Access Gateway for Energy & Science Beta (PAGES Beta)

    Rapp, Vi H.; DeFilippo, Anthony; Saxena, Samveg; Chen, Jyh-Yuan; Dibble, Robert W.; Nishiyama, Atsushi; Moon, Ahsa; Ikeda, Yuji

    2012-01-01

    Amore » microwave-assisted spark plug was used to extend the lean operating limit (lean limit) and reduce emissions of an engine burning methane-air. In-cylinder pressure data were collected at normalized air-fuel ratios of λ = 1.46, λ = 1.51, λ = 1.57, λ = 1.68, and λ = 1.75. For each λ, microwave energy (power supplied to the magnetron per engine cycle) was varied from 0 mJ (spark discharge alone) to 1600 mJ. At lean conditions, the results showed adding microwave energy to a standard spark plug discharge increased the number of complete combustion cycles, improving engine stability as compared to spark-only operation. Addition of microwave energy also increased the indicated thermal efficiency by 4% at λ = 1.68. At λ = 1.75, the spark discharge alone was unable to consistently ignite the air-fuel mixture, resulting in frequent misfires. Although microwave energy produced more consistent ignition than spark discharge alone at λ = 1.75, 59% of the cycles only partially burned. Overall, the microwave-assisted spark plug increased engine performance under lean operating conditions (λ = 1.68) but did not affect operation at conditions closer to stoichiometric.« less

  15. Dynamic instabilities in spark-ignited combustion engines with high exhaust gas recirculation

    SciTech Connect (OSTI)

    Daw, C Stuart; FINNEY, Charles E A

    2011-01-01

    We propose a cycle-resolved dynamic model for combustion instabilities in spark-ignition engines operating with high levels of exhaust gas recirculation (EGR). High EGR is important for increasing fuel efficiency and implementing advanced low-emission combustion modes such as homogenous charge compression ignition (HCCI). We account for the complex combustion response to cycle-to-cycle feedback by utilizing a global probability distribution that describes the pre-spark state of in-cylinder fuel mixing. The proposed model does a good job of simulating combustion instabilities observed in both lean-fueling engine experiments and in experiments where nitrogen dilution is used to simulate some of the combustion inhibition of EGR. When used to simulate high internal EGR operation, the model exhibits a range of global bifurcations and chaos that appear to be very robust. We use the model to show that it should be possible to reduce high EGR combustion instabilities by switching from internal to external EGR. We also explain why it might be helpful to deliberately stratify the fuel in the pre-spark gas mixture. It might be possible to extend the simple approach used in this model to other chemical reaction systems with spatial inhomogeneity.

  16. Conversion of a diesel engine to a spark ignition natural gas engine

    SciTech Connect (OSTI)

    1996-09-01

    Requirements for alternatives to diesel-fueled vehicles are developing, particularly in urban centers not in compliance with mandated air quality standards. An operator of fleets of diesel- powered vehicles may be forced to either purchase new vehicles or equip some of the existing fleets with engines designed or modified to run on alternative fuels. In converting existing vehicles, the operator can either replace the existing engine or modify it to burn an alternative fuel. Work described in this report addresses the problem of modifying an existing diesel engine to operate on natural gas. Tecogen has developed a technique for converting turbocharged automotive diesel engines to operate as dedicated spark-ignition engines with natural gas fuel. The engine cycle is converted to a more-complete-expansion cycle in which the expansion ratio of the original engine is unchanged while the effective compression ratio is lowered, so that engine detonation is avoided. The converted natural gas engine, with an expansion ratio higher than in conventional spark- ignition natural gas engines, offers thermal efficiency at wide-open- throttle conditions comparable to its diesel counterpart. This allows field conversion of existing engines. Low exhaust emissions can be achieved when the engine is operated with precise control of the fuel air mixture at stoichiometry with a 3-way catalyst. A Navistar DTA- 466 diesel engine with an expansion ratio of 16.5 to 1 was converted in this way, modifying the cam profiles, increasing the turbocharger boost pressure, incorporating an aftercooler if not already present, and adding a spark-ignition system, natural gas fuel management system, throttle body for load control, and an electronic engine control system. The proof-of-concept engine achieved a power level comparable to that of the diesel engine without detonation. A conversion system was developed for the Navistar DT 466 engine. NOx emissions of 1.5 g/bhp-h have been obtained.

  17. Methanol as a fuel for a lean turbocharged spark ignition engine

    SciTech Connect (OSTI)

    Pannone, G.M.; Johnson, R.T.

    1989-01-01

    Lean turbocharged operation with methanol was characterized using a single-cylinder spark, ignition engine. Efficiency, exhaust emissions, and combustion properties were measured over a range of air/fuel ratios at two naturally-aspirated and three turbocharged conditions. When compared to stoichiometric, naturally-aspirated operation, the lean turbocharged conditions improved efficiency while reducing carbon monoxide and oxides of nitrogen emissions. However, unburned fuel and aldehyde emissions increased. If used in conjunction with an oxidizing catalyst and appropriate feedback controls, lean turbocharged operation has the potential of improving efficiency and exhaust emissions performance over a stoichiometric, three-way catalyst system.

  18. Thermal ignition combustion system

    DOE Patents [OSTI]

    Kamo, Roy (Columbus, IN); Kakwani, Ramesh M. (Columbus, IN); Valdmanis, Edgars (Columbus, IN); Woods, Melvins E. (Columbus, IN)

    1988-01-01

    The thermal ignition combustion system comprises means for providing walls defining an ignition chamber, the walls being made of a material having a thermal conductivity greater than 20 W/m.degree. C. and a specific heat greater than 480 J/kg.degree. C. with the ignition chamber being in constant communication with the main combustion chamber, means for maintaining the temperature of the walls above a threshold temperature capable of causing ignition of a fuel, and means for conducting fuel to the ignition chamber.

  19. Thermal ignition combustion system

    DOE Patents [OSTI]

    Kamo, R.; Kakwani, R.M.; Valdmanis, E.; Woods, M.E.

    1988-04-19

    The thermal ignition combustion system comprises means for providing walls defining an ignition chamber, the walls being made of a material having a thermal conductivity greater than 20 W/m C and a specific heat greater than 480 J/kg C with the ignition chamber being in constant communication with the main combustion chamber, means for maintaining the temperature of the walls above a threshold temperature capable of causing ignition of a fuel, and means for conducting fuel to the ignition chamber. 8 figs.

  20. Fiber laser coupled optical spark delivery system

    DOE Patents [OSTI]

    Yalin, Azer (Fort Collins, CO); Willson, Bryan (Fort Collins, CO); Defoort, Morgan (Fort Collins, CO); Joshi, Sachin (Fort Collins, CO); Reynolds, Adam (Fort Collins, CO)

    2008-03-04

    A spark delivery system for generating a spark using a laser beam is provided, and includes a laser light source and a laser delivery assembly. The laser delivery assembly includes a hollow fiber and a launch assembly comprising launch focusing optics to input the laser beam in the hollow fiber. The laser delivery assembly further includes exit focusing optics that demagnify an exit beam of laser light from the hollow fiber, thereby increasing the intensity of the laser beam and creating a spark. Other embodiments use a fiber laser to generate a spark. Embodiments of the present invention may be used to create a spark in an engine. Yet other embodiments include collecting light from the spark or a flame resulting from the spark and conveying the light for diagnostics. Methods of using the spark delivery systems and diagnostic systems are provided.

  1. Performance and emissions characteristics of alternative fuels in spark ignition engines

    SciTech Connect (OSTI)

    Swain, M.R.; Maxwell, R.L.; Swain, M.N.; Bedsworth, K.; Adt, R.R. Jr.; Pappas, J.M.

    1984-01-01

    A formal ongoing program to characterize the performance and exhaust characteristics of automotive-type powerplants fueled by conventional and alternative fuels is reported. This report contains the information obtained during the past three years when four alternative fuels and two baseline fuels were evaluated in three engines. The four alternative fuels were a simulated gasoline made to represent coal derived gasoline, methyl aryl ethers blended at the 10% level in an unleaded gasoline, gasoline made from methanol, and a blend of Indolene plus methanol and higher alcohols. The two baseline fuels were, Indolene and Gulf unleaded regular gasoline. The engines tested were a pre-mixed carbureted SI (spark ignition) engine, a carbureted three-valve stratified-charge SI engine and a pre-mixed carbureted SI engine with a closed-loop three-way catalyst emission control system.

  2. Development of High Efficiency Clean Combustion Engine Designs for Spark-Ignition and Compression-Ignition Internal Combustion Engines

    SciTech Connect (OSTI)

    Marriott, Craig; Gonzalez, Manual; Russell, Durrett

    2011-06-30

    This report summarizes activities related to the revised STATEMENT OF PROJECT OBJECTIVES (SOPO) dated June 2010 for the Development of High-Efficiency Clean Combustion engine Designs for Spark-Ignition and Compression-Ignition Internal Combustion Engines (COOPERATIVE AGREEMENT NUMBER DE-FC26-05NT42415) project. In both the spark- (SI) and compression-ignition (CI) development activities covered in this program, the goal was to develop potential production-viable internal combustion engine system technologies that both reduce fuel consumption and simultaneously met exhaust emission targets. To be production-viable, engine technologies were also evaluated to determine if they would meet customer expectations of refinement in terms of noise, vibration, performance, driveability, etc. in addition to having an attractive business case and value. Prior to this activity, only proprietary theoretical / laboratory knowledge existed on the combustion technologies explored The research reported here expands and develops this knowledge to determine series-production viability. Significant SI and CI engine development occurred during this program within General Motors, LLC over more than five years. In the SI program, several engines were designed and developed that used both a relatively simple multi-lift valve train system and a Fully Flexible Valve Actuation (FFVA) system to enable a Homogeneous Charge Compression Ignition (HCCI) combustion process. Many technical challenges, which were unknown at the start of this program, were identified and systematically resolved through analysis, test and development. This report documents the challenges and solutions for each SOPO deliverable. As a result of the project activities, the production viability of the developed clean combustion technologies has been determined. At this time, HCCI combustion for SI engines is not considered production-viable for several reasons. HCCI combustion is excessively sensitive to control variables such as internal dilution level and charge temperature. As a result, HCCI combustion has limited robustness when variables exceed the required narrow ranges determined in this program. HCCI combustion is also not available for the entire range of production engine speeds and loads, (i.e., the dynamic range is limited). Thus, regular SI combustion must be employed for a majority of the full dynamic range of the engine. This degrades the potential fuel economy impact of HCCI combustion. Currently-available combustion control actuators for the simple valve train system engine do not have the authority for continuous air - fuel or torque control for managing the combustion mode transitions between SI and HCCI and thus, require further refinement to meet customer refinement expectations. HCCI combustion control sensors require further development to enable robust long-term HCCI combustion control. Finally, the added technologies required to effectively manage HCCI combustion such as electric cam phasers, central direct fuel injection, cylinder pressure sensing, high-flow exhaust gas recirculation system, etc. add excessive on-engine cost and complexity that erodes the production-viability business

  3. Fiber coupled optical spark delivery system

    DOE Patents [OSTI]

    Yalin, Azer (Fort Collins, CO); Willson, Bryan (Fort Collins, CO); Defoort, Morgan (Fort Collins, CO)

    2008-08-12

    A spark delivery system for generating a spark using a laser beam is provided, the spark delivery system including a laser light source and a laser delivery assembly. The laser delivery assembly includes a hollow fiber and a launch assembly comprising launch focusing optics to input the laser beam in the hollow fiber. In addition, the laser delivery assembly includes exit focusing optics that demagnify an exit beam of laser light from the hollow fiber, thereby increasing the intensity of the laser beam and creating a spark. In accordance with embodiments of the present invention, the assembly may be used to create a spark in a combustion engine. In accordance with other embodiments of the present invention, a method of using the spark delivery system is provided. In addition, a method of choosing an appropriate fiber for creating a spark using a laser beam is also presented.

  4. Ignition assist systems for direct-injected, diesel cycle, medium-duty alternative fuel engines: Final report phase 1

    SciTech Connect (OSTI)

    Chan, A.K.

    2000-02-23

    This report is a summary of the results of Phase 1 of this contract. The objective was to evaluate the potential of assist technologies for direct-injected alternative fuel engines vs. glow plug ignition assist. The goal was to demonstrate the feasibility of an ignition system life of 10,000 hours and a system cost of less than 50% of the glow plug system, while meeting or exceeding the engine thermal efficiency obtained with the glow plug system. There were three tasks in Phase 1. Under Task 1, a comprehensive review of feasible ignition options for DING engines was completed. The most promising options are: (1) AC and the ''SmartFire'' spark, which are both long-duration, low-power (LDLP) spark systems; (2) the short-duration, high-power (SDHP) spark system; (3) the micropilot injection ignition; and (4) the stratified charge plasma ignition. Efforts concentrated on investigating the AC spark, SmartFire spark, and short-duration/high-power spark systems. Using proprietary pricing information, the authors predicted that the commercial costs for the AC spark, the short-duration/high-power spark and SmartFire spark systems will be comparable (if not less) to the glow plug system. Task 2 involved designing and performing bench tests to determine the criteria for the ignition system and the prototype spark plug for Task 3. The two most important design criteria are the high voltage output requirement of the ignition system and the minimum electrical insulation requirement for the spark plug. Under Task 3, all the necessary hardware for the one-cylinder engine test was designed. The hardware includes modified 3126 cylinder heads, specially designed prototype spark plugs, ignition system electronics, and parts for the system installation. Two 3126 cylinder heads and the SmartFire ignition system were procured, and testing will begin in Phase 2 of this subcontract.

  5. Turbocharged Spark Ignited Direct Injection - A Fuel Economy...

    Office of Energy Efficiency and Renewable Energy (EERE) Indexed Site

    E85 Optimized Engine Two-Stage Variable Compression Ratio (VCR) System to Increase Efficiency in Gasoline Powertrains Cold-Start Performance and Emissions Behavior of Alcohol Fuels ...

  6. Improving the Efficiency of Spark Ignited, Stoichiometric Natural...

    Office of Energy Efficiency and Renewable Energy (EERE) Indexed Site

    Advanced Natural Gas Reciprocating Engines (ARES) - Presentation by Cummins, Inc., June 2011 Compact, electro-hydraulic, variable valve actuation system providing variable lift, ...

  7. Critical radius for sustained propagation of spark-ignited spherical flames

    SciTech Connect (OSTI)

    Kelley, Andrew P.; Jomaas, Grunde; Law, Chung K.

    2009-05-15

    An experimental study was performed to determine the requirements for sustained propagation of spark-ignited hydrogen-air and butane-air flames at atmospheric and elevated pressures. Results show that sustained propagation is always possible for mixtures whose Lewis number is less than unity, as long as a flame can be initially established. However, for mixtures whose Lewis number is greater than unity, sustained propagation depends on whether the initially ignited flame can attain a minimum radius. This minimum radius was determined for mixtures of different equivalence ratios and pressures, and was found to agree moderately well with the theoretically predicted critical radius beyond which there is no solution for the adiabatic, quasi-steady propagation of the spherical flame. The essential roles of pressure, detailed chemistry, and the need to use local values in the quantitative evaluation of the flame response parameters are emphasized. (author)

  8. Spark discharge trace element detection system

    DOE Patents [OSTI]

    Adler-Golden, S.; Bernstein, L.S.; Bien, F.

    1988-08-23

    A spark discharge trace element detection system is provided which includes a spark chamber including a pair of electrodes for receiving a sample of gas to be analyzed at no greater than atmospheric pressure. A voltage is provided across the electrodes for generating a spark in the sample. The intensity of the emitted radiation in at least one primary selected narrow band of the radiation is detected. Each primary band corresponds to an element to be detected in the gas. The intensity of the emission in each detected primary band is integrated during the afterglow time interval of the spark emission and a signal representative of the integrated intensity of the emission in each selected primary bond is utilized to determine the concentration of the corresponding element in the gas. 12 figs.

  9. Premix charge, compression ignition combustion system optimization...

    Office of Energy Efficiency and Renewable Energy (EERE) Indexed Site

    Premix charge, compression ignition combustion system optimization Premix charge, compression ignition combustion system optimization Presentation given at DEER 2006, August 20-24,...

  10. Lean-burn hydrogen spark-ignited engines: the mechanical equivalent to the fuel cell

    SciTech Connect (OSTI)

    Aceves, S.M.; Smith, J.R.

    1996-10-01

    Fuel cells are considered as the ideal power source for future vehicles, due to their high efficiency and low emissions. However, extensive use of fuel cells in light-duty vehicles is likely to be years away, due to their high manufacturing cost. Hydrogen-fueled, spark-ignited, homogeneous-charge engines offer a near-term alternative to fuel cells. Hydrogen in a spark-ignited engine can be burned at very low equivalence ratios, so that NO[sub x] emissions can be reduced to less than 10 ppm without catalyst. HC and CO emissions may result from oxidation of engine oil, but by proper design are negligible (a few ppm). Lean operation also results in increased indicated efficiency due to the thermodynamic properties of the gaseous mixture contained in the cylinder. The high effective octane number of hydrogen allows the use of a high compression ratio, further increasing engine efficiency. In this paper, a simplified engine model is used for predicting hydrogen engine efficiency and emissions. The model uses basic thermodynamic equations for the compression and expansion processes, along with an empirical correlation for heat transfer, to predict engine indicated efficiency. A friction correlation and a supercharger/turbocharger model are then used to calculate brake thermal efficiency. The model is validated with many 1345 experimental points obtained in a recent evaluation of a hydrogen research engine. The experimental data are used to adjust the empirical constants in the heat release rate and heat transfer correlation. The adjusted engine model predicts pressure traces, indicated efficiency and NO,, emissions with good accuracy over the range of speed, equivalence ratio and manifold pressure experimentally covered.

  11. Ethanol Blend Effects On Direct Injection Spark-Ignition Gasoline Vehicle Particulate Matter Emissions

    SciTech Connect (OSTI)

    Storey, John Morse; Lewis Sr, Samuel Arthur; Barone, Teresa L

    2010-01-01

    Direct injection spark-ignition (DISI) gasoline engines can offer better fuel economy and higher performance over their port fuel-injected counterparts, and are now appearing increasingly in more U.S. vehicles. Small displacement, turbocharged DISI engines are likely to be used in lieu of large displacement engines, particularly in light-duty trucks and sport utility vehicles, to meet fuel economy standards for 2016. In addition to changes in gasoline engine technology, fuel composition may increase in ethanol content beyond the 10% allowed by current law due to the Renewable Fuels Standard passed as part of the 2007 Energy Independence and Security Act (EISA). In this study, we present the results of an emissions analysis of a U.S.-legal stoichiometric, turbocharged DISI vehicle, operating on ethanol blends, with an emphasis on detailed particulate matter (PM) characterization. Gaseous species, particle mass, and particle number concentration emissions were measured for the Federal Test Procedure urban driving cycle (FTP 75) and the more aggressive US06 cycle. Particle number-size distributions and organic to elemental carbon ratios (OC/EC) were measured for 30 MPH and 80 MPH steady-state operation. In addition, particle number concentration was measured during wide open throttle accelerations (WOTs) and gradual accelerations representative of the FTP 75. For the gaseous species and particle mass measurements, dilution was carried out using a full flow constant volume sampling system (CVS). For the particle number concentration and size distribution measurements, a micro-tunnel dilution system was employed. The vehicles were fueled by a standard test gasoline and 10% (E10) and 20% (E20) ethanol blends from the same supplier. The particle mass emissions were approximately 3 and 7 mg/mile for the FTP75 and US06, respectively, with lower emissions for the ethanol blends. During steady-state operation, the geometric mean diameter of the particle-number size distribution remained approximately the same (50 nm) but the particle number concentration decreased with increasing ethanol content in the fuel. In addition, increasing ethanol content significantly reduced the number concentration of 50 and 100 nm particles during gradual and WOT accelerations.

  12. Optical diagnostics integrated with laser spark delivery system

    DOE Patents [OSTI]

    Yalin, Azer (Fort Collins, CO); Willson, Bryan (Fort Collins, CO); Defoort, Morgan (Fort Collins, CO); Joshi, Sachin (Fort Collins, CO); Reynolds, Adam (Fort Collins, CO)

    2008-09-02

    A spark delivery system for generating a spark using a laser beam is provided, and includes a laser light source and a laser delivery assembly. The laser delivery assembly includes a hollow fiber and a launch assembly comprising launch focusing optics to input the laser beam in the hollow fiber. The laser delivery assembly further includes exit focusing optics that demagnify an exit beam of laser light from the hollow fiber, thereby increasing the intensity of the laser beam and creating a spark. Other embodiments use a fiber laser to generate a spark. Embodiments of the present invention may be used to create a spark in an engine. Yet other embodiments include collecting light from the spark or a flame resulting from the spark and conveying the light for diagnostics. Methods of using the spark delivery systems and diagnostic systems are provided.

  13. Igniter for gas discharge pipe with a flame detection system

    SciTech Connect (OSTI)

    Guerra, R.E.

    1990-03-06

    This patent describes a method of burning waste gas, using an igniter of the type having a nozzle, a main gas conduit extending to the nozzle, and an electrical spark means for creating a spark in the nozzle. It comprises: mounting the igniter to a waste gas discharge pipe with the nozzle directed across the opening of the gas discharge pipe; supplying a gaseous fuel to the main gas conduit; igniting the gaseous fuel with the electrical spark means, creating a flame for igniting the waste gas being discharged from the gas discharge pipe; providing the igniter with an auxiliary gas line extending to the vicinity of the nozzle; and supplying a second and lower volume source of waste gas to the auxiliary gas line for burning at the nozzle.

  14. Laser Spark Plug Development

    SciTech Connect (OSTI)

    McIntyre, D.L.; Richardson, S.W.; Woodruff, S.D.; McMillian, M.H.; Guutam, M.

    2007-04-01

    To meet the ignition system needs of large bore high pressure lean burn natural gas engines a laser diode side pumped passively Q-switched laser igniter was designed and tested. The laser was designed to produce the optical intensities needed to initiate ignition in a lean burn high brake mean effective pressure (BMEP) engine. The experimentation explored a variety of optical and electrical input parameters that when combined produced a robust spark in air. The results show peak power levels exceeding 2 MW and peak focal intensities above 400 GW/cm2. Future research avenues and current progress with the initial prototype are presented and discussed.

  15. Hot surface ignition system control module with accelerated igniter warm-up test program

    SciTech Connect (OSTI)

    Brown, B.T.

    1986-10-07

    This patent describes a gas burner control system which consists of: a burner; an electrical resistance igniter for igniting the burner; valve means for controlling flow of gas to the burner; and a control module, including a microcomputer, for controlling operation of the igniter and the valve means, the microcomputer being programmed to provide a preselected igniter warm-up time period for enabling the igniter to attain a temperature sufficient to ignite gas, the microcomputer being further programmed to provide a test routine including a program for providing an accelerated igniter warm-up time period which is shorter than the preselected igniter warm-up time period but sufficiently long for enabling the igniter to attain at least the minimum temperature required to ignite gas, the program in the test routine being executed in response to a unique signal effected by the control module and a test device which is external from and detachably connected to the control module.

  16. Premix charge, compression ignition combustion system optimization |

    Office of Energy Efficiency and Renewable Energy (EERE) Indexed Site

    Department of Energy Premix charge, compression ignition combustion system optimization Premix charge, compression ignition combustion system optimization Presentation given at DEER 2006, August 20-24, 2006, Detroit, Michigan. Sponsored by the U.S. DOE's EERE FreedomCar and Fuel Partnership and 21st Century Truck Programs. PDF icon 2006_deer_gustafson.pdf More Documents & Publications Advanced Combustion Technology to Enable High Efficiency Clean Combustion Heavy-Duty HCCI Development

  17. A comparison of ethanol and butanol as oxygenates using a direct-injection, spark-ignition (DISI) engine.

    SciTech Connect (OSTI)

    Wallner, T.; Miers, S. A.; McConnell, S.

    2009-05-01

    This study was designed to evaluate a 'what if' scenario in terms of using butanol as an oxygenate in place of ethanol in an engine calibrated for gasoline operation. No changes to the stock engine calibration were performed for this study. Combustion analysis, efficiency, and emissions of pure gasoline, 10% ethanol, and 10% butanol blends in a modern direct-injection four-cylinder spark-ignition engine were analyzed. Data were taken at engine speeds of 1000 rpm up to 4000 rpm with load varying from 0 N m (idle) to 150 N m. Relatively minor differences existed between the three fuels for the combustion characteristics such as heat release rate, 50% mass fraction burned, and coefficient of variation in indicated mean effective pressure at low and medium engine loads. However at high engine loads the reduced knock resistance of the butanol blend forced the engine control unit to retard the ignition timing substantially, compared with the gasoline baseline and, even more pronounced, compared with the ethanol blend. Brake specific volumetric fuel consumption, which represented a normalized volumetric fuel flow rate, was lowest for the gasoline baseline fuel due to the higher energy density. The 10% butanol blend had a lower volumetric fuel consumption compared with the ethanol blend, as expected, based on energy density differences. The results showed little difference in regulated emissions between 10% ethanol and 10% butanol. The ethanol blend produced the highest peak specific NO{sub x} due to the high octane rating of ethanol and effective antiknock characteristics. Overall, the ability of butanol to perform equally as well as ethanol from an emissions and combustion standpoint, with a decrease in fuel consumption, initially appears promising. Further experiments are planned to explore the full operating range of the engine and the potential benefits of higher blend ratios of butanol.

  18. Particulate Matter Sampling and Volatile Organic Compound Removal for Characterization of Spark Ignited Direct Injection Engine Emissions

    SciTech Connect (OSTI)

    Matthias, Nicholas; Farron, Carrie; Foster, David E.; Andrie, Michael; Krieger, Roger; Najt, Paul M.; Narayanaswamy, Kushal; Solomon, Arun S.; Zelenyuk, Alla

    2012-01-01

    More stringent emissions regulations are continually being proposed to mitigate adverse human health and environmental impacts of internal combustion engines. With that in mind, it has been proposed that vehicular particulate matter (PM) emissions should be regulated based on particle number in addition to particle mass. One aspect of this project is to study different sample handling methods for number based aerosol measurements, specifically, two different methods for removing volatile organic compounds (VOCs). One method is a thermodenuder (TD) and the other is an evaporative chamber/diluter (EvCh). These sample handling methods have been implemented in an engine test cell with a spark ignited direct injection (SIDI) engine. The engine was designed for stoichiometric, homogeneous combustion. SIDI is of particular interest for improved fuel efficiency compared to other SI engines, however, the efficiency benefit comes with greater PM emissions and may therefore be subject to the proposed number based PM regulation. Another aspect of this project is to characterize PM from this engine in terms of particle number and composition.

  19. Particulate Matter Sampling and Volatile Organic Compound Removal for Characterization of Spark Ignited Direct Injection Engine Emissions

    SciTech Connect (OSTI)

    Matthias, Nicholas; Farron, Carrie; Foster, David E.; Andrie, Michael; Krieger, Roger; Najt, Paul; Narayanaswamy, Kushal; Solomon, Arun S.; Zelenyuk, Alla

    2012-01-01

    More stringent emissions regulations are continually being proposed to mitigate adverse human health and environmental impacts of internal combustion engines. With that in mind, it has been proposed that vehicular particulate matter (PM) emissions should be regulated based on particle number in addition to particle mass. One aspect of this project is to study different sample handling methods for number based aerosol measurements, specifically, two different methods for removing volatile organic compounds (VOCs). One method is a thermodenuder (TD) and the other is an evaporative chamber/diluter (EvCh). These sample handling methods have been implemented in an engine test cell with a spark ignited direct injection (SIDI) engine. The engine was designed for stoichiometric, homogeneous combustion. SIDI is of particular interest for improved fuel efficiency compared to other SI engines, however, the efficiency benefit comes with greater PM emissions and may therefore be subject to the proposed number based PM regulation. Another aspect of this project is to characterize PM from this engine in terms of particle number and composition

  20. Mechanisms of particulate matter formation in spark-ignition engines. 2: Effect of fuel, oil, and catalyst parameters

    SciTech Connect (OSTI)

    Kayes, D.; Hochgreb, S.

    1999-11-15

    A combined experimental and modeling effort was performed in order to understand how particulate matter (PM) is formed in spark-ignition (SI) internal combustion engines. Fuel type and fuel/air ratio strongly affect particle concentrations. PM emissions vary by up to 6 orders of magnitude between fuels at the same fuel/air ratio. Minimum PM concentrations are emitted at a global fuel/air ratio within 10% of stoichiometric, with the exact value depending on the particular fuel. Concentrations can increase by more than 3 orders of magnitude when the fuel/air ratio is either increased or decreased 30% from stoichiometric. Particles derived from oil consumption were found to be between 0 and 40% of the PM concentration for the oils used in the present experiments. Differences in PM emissions with and without the catalytic converter are not statistically significant. Particulate number and mass concentrations plus particle sizes are addressed in this paper, as is the correlation between PM and hydrocarbon (HC) emissions.

  1. Spark gap switch system with condensable dielectric gas

    DOE Patents [OSTI]

    Thayer, III, William J. (Kent, WA)

    1991-01-01

    A spark gap switch system is disclosed which is capable of operating at a high pulse rate comprising an insulated switch housing having a purging gas entrance port and a gas exit port, a pair of spaced apart electrodes each having one end thereof within the housing and defining a spark gap therebetween, an easily condensable and preferably low molecular weight insulating gas flowing through the switch housing from the housing, a heat exchanger/condenser for condensing the insulating gas after it exits from the housing, a pump for recirculating the condensed insulating gas as a liquid back to the housing, and a heater exchanger/evaporator to vaporize at least a portion of the condensed insulating gas back into a vapor prior to flowing the insulating gas back into the housing.

  2. Particulate Matter Sampling and Volatile Organic Compound Removal for Characterization of Spark Ignited Direct Injection Engine Emissions

    SciTech Connect (OSTI)

    Matthias, Nick; Farron, Carrie; Foster, David E.; Andrie, Mike; Krieger, Roger; Najt, Paul; Narayanaswamy, Kushal; Solomon, Arun; Zelenyuk, Alla

    2012-01-01

    More stringent emissions regulations are continually being proposed to mitigate adverse human health and environmental impacts of internal combustion. With that in mind, it has been proposed that vehicular particulate matter (PM) emissions should be regulated based on particle number in addition to particle mass. One aspect of this project is to study different sample handling methods for number based aerosol measurements, specifically, two different methods for removing volatile organic compounds (VOCs) from an aerosol sample. One method is a Dekati Thermodenuder (TD) and the other is an evaporative chamber/diluter (EvCh). These sample handling methods have been implemented for this project in an engine test cell built around a direct injection spark ignited (DISI) engine. The engine was designed for stoichiometric, homogeneous combustion. Direct injection is of particular interest for improved fuel efficiency but this comes with the production of a significant amount of (PM) and may therefore be subject to the proposed number based regulation. Another aspect of this project is to characterize PM from this engine in terms of particle number and composition. The first interesting observation is that PM number distributions, acquired using a TSI SMPS, have a large accumulation mode (30-294 nm) but a very small nuclei mode (8-30 nm). This is understood to represent a lack of condensation particles meaning that neither the exhaust conditions nor the sample handling conditions are conducive to condensation. This lack of nuclei mode does not, however, represent a lack of VOCs in the sample. It has been observed, using mass spectral analysis (limited to PM>50 nm), that PM from the DISI engine has approximately 40% organic content through varying operating conditions. This begs the question of how effective different sample handling methods are at removing these VOCs. For one specific operating condition, called Cold Start, the un-treated PM was 40% organic. The TD reduced this by 7% while the EvCh reduced it by 13%. For other operating conditions, PM treated for volatile removal actually exhibited an increase in organic fraction on the order of 5%. This addition appears to be sensitive to the gaseous hydrocarbon concentrations in the exhaust although a precise correlation has not yet been derived. It has been concluded that VOCs are tightly bound to the PM carbon core and thus are not effectively removed by either treatment method.

  3. Active flow control for maximizing performance of spark ignited stratified charge engines. Final report

    SciTech Connect (OSTI)

    Fedewa, Andrew; Stuecken, Tom; Timm, Edward; Schock, Harold J.; Shih, Tom-I.P.; Koochesfahani, Manooch; Brereton, Giles

    2002-10-15

    Reducing the cycle-to-cycle variability present in stratified-charge engines is an important step in the process of increasing their efficiency. As a result of this cycle-to-cycle variability, fuel injection systems are calibrated to inject more fuel than necessary, in an attempt to ensure that the engines fire on every cycle. When the cycle-to-cycle variability is lowered, the variation of work per cycle is reduced and the lean operating limit decreases, resulting in increased fuel economy. In this study an active flow control device is used to excite the intake flow of an engine at various frequencies. The goal of this excitation is to control the way in which vortices shed off of the intake valve, thus lowering the cycle-to-cycle variability in the flow field. This method of controlling flow is investigated through the use of three engines. The results of this study show that the active flow control device did help to lower the cycle-to-cycle variability of the in-cylinder flow field; however, the reduction did not translate directly into improved engine performance.

  4. IMPROVEMENT TO PIPELINE COMPRESSOR ENGINE RELIABILITY THROUGH RETROFIT MICRO-PILOT IGNITION SYSTEM-PHASE I

    SciTech Connect (OSTI)

    Ted Bestor

    2003-03-04

    This report documents the first year's effort towards a 3-year program to develop micropilot ignition systems for existing pipeline compressor engines. In essence, all Phase I goals and objectives were met. We intend to proceed with the Phase II research plan, as set forth by the applicable Research Management Plan. The objective for Phase I was to demonstrate the feasibility of micropilot ignition for large bore, slow speed engines operating at low compression ratios. The primary elements of Micropilot Phase I were to develop a single-cylinder test chamber to study the injection of pilot fuel into a combustion cylinder and to develop, install and test a multi-cylinder micropilot ignition system for a 4-cylinder, natural gas test engine. In all, there were twelve (12) tasks defined and executed to support these two (2) primarily elements in a stepwise fashion. Task-specific approaches and results are documented in this report. Research activities for Micropilot Phase I were conducted with the understanding that the efforts are expected to result in a commercial product to capture and disseminate the efficiency and environmental benefits of this new technology. An extensive state-of-art review was conducted to leverage the existing body of knowledge of micropilot ignition with respect to retrofit applications. Additionally, commercially-available fuel injection products were identified and applied to the program where appropriate. This approach will minimize the overall time-to-market requirements, while meeting performance and cost criteria. The four-cylinder prototype data was encouraging for the micro-pilot ignition technology when compared to spark ignition. Initial testing results showed: (1) Brake specific fuel consumption of natural gas was improved from standard spark ignition across the map, 1% at full load and 5% at 70% load. (2) 0% misfires for all points on micropilot ignition. Fuel savings were most likely due to this percent misfire improvement. (3) THC (Total Hydrocarbon) emissions were improved significantly at light load, 38% at 70% load. (4) VOC (Volatile Organic Compounds) emissions were improved above 80% load. (5) Coefficient of Variance for the IMEP (Indicated Mean Effective Pressure) was significantly less at lower loads, 76% less at 70%. These preliminary results will be substantiated and enhanced during Phase II of the Micropilot Ignition program.

  5. On the study of threshold intensity dependence on the gain and loss processes in laser induced spark ignition of molecular hydrogen

    SciTech Connect (OSTI)

    Omar, M. M. Aboulfotouh, A. M.; Gamal, Y. E. E.

    2015-03-30

    In the present work, a numerical analysis is performed to investigate the comparative contribution of the mechanisms responsible for electron gain and losses in laser spark ignition and plasma formation of H{sub 2}. The analysis considered H{sub 2} over pressure range 150 -3000 torr irradiated by a Nd:YAG laser radiation at wavelengths 1064 and 532?nm with pulse length 5.5?ns. The study based on a modified electron cascade model by one of the authors which solves numerically the time dependent Boltzmann equation as well as a set of rate equations that describe the rate of change of the excited states population. The model includes most of the physical processes that might take place during the interaction. Computations of The threshold intensity are performed for the combined and separate contribution of each of the gain and loss processes. Reasonable agreement with the measured values over the tested pressure range is obtained only for the case of the combined contribution. Basing on the calculation of the electron energy distribution function, the determined relations of the time evolution of the electrons density for selected values of the tested gas pressure region revealed that photo-ionization of the excited states could determine the time of electron generation and hence spark ignition. Collisional ionization contributes to this phenomenon only at the high pressure regime. Loss processes due to electron diffusion, vibrational excitation are found to have significant effect over examined pressure values for the two applied laser wavelengths.

  6. Laser Ignition and Diagnostic Systems Delivered by Flexible Optical...

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    (441 KB) Technology Marketing Summary Laser-based ignition systems based on state-of-the-art optical fibers and sophisticated new delivery strategies that provide both engine...

  7. Influence of fuel variables on the operation of automotive open and pre-chamber diesel and spark ignited stratified charge engines: a literature study covering petroleum and syncrude derived fuels

    SciTech Connect (OSTI)

    Needham, J.R.

    1980-09-01

    A literature study has been carried out to ascertain the influence of fuels and fuel variables on the operation of automotive diesel and spark ignited stratified charge engines with a view to understanding the impact of future fuels derived from Syncrude. The findings from the search are presented and discussed in detail, conclusions reached and recommendations made.

  8. Ignitor with stable low-energy thermite igniting system

    DOE Patents [OSTI]

    Kelly, Michael D. (West Alexandria, OH); Munger, Alan C. (Miamisburg, OH)

    1991-02-05

    A stable compact low-energy igniting system in an ignitor utilizes two components, an initiating charge and an output charge. The initiating charge is a thermite in ultra-fine powder form compacted to 50-70% of theoretical maximum density and disposed in a cavity of a header of the ignitor adjacent to an electrical ignition device, or bridgewire, mounted in the header cavity. The initiating charge is ignitable by operation of the ignition device in a hot-wire mode. The output charge is a thermite in high-density consoladated form compacted to 90-99% of theoretical maximum density and disposed adjacent to the initiating charge on an opposite end thereof from the electrical ignition device and ignitable by the initiating charge. A sleeve is provided for mounting the output charge to the ignitor header with the initiating charge confined therebetween in the cavity.

  9. IMPROVEMENT TO PIPELINE COMPRESSOR ENGINE RELIABILITY THROUGH RETROFIT MICRO-PILOT IGNITION SYSTEM

    SciTech Connect (OSTI)

    Ted Bestor

    2004-06-01

    This report documents the second year's effort towards a 3-year program to develop micropilot ignition systems for existing pipeline compressor engines. In essence, all Phase II goals and objectives were met. We intend to proceed with the Phase III research plan, as set forth by the applicable Research Management Plan. The objective for Phase II was to further develop and optimize the micropilot ignition system for large bore, slow speed engines operating at low compression ratios. The primary elements of Micropilot Phase II were to evaluate the results for the 4-cylinder system prototype developed for Phase I, then optimize this system to demonstrate the technology's readiness for the field demonstration phase. In all, there were twelve (12) tasks defined and executed to support objectives in a stepwise fashion. Task-specific approaches and results are documented in this report. Research activities for Micropilot Phase II were conducted with the understanding that the efforts are expected to result in a commercial product to capture and disseminate the efficiency and environmental benefits of this new technology. Commercially-available fuel injection products were identified and applied to the program where appropriate. Modifications to existing engine components were kept to a minimum. This approach will minimize the overall time-to-market requirements, while meeting performance and cost criteria. The optimized four-cylinder system data demonstrated significant progress compared to Phase I results, as well as traditional spark ignition systems. An extensive testing program at the EECL using the GMV-4 test engine demonstrated that: (1) In general, the engine operated more stable fewer misfires and partial combustion events when using the 3-hole injectors compared to the 5-hole injectors used in Phase I. (2) The engine had, in general, a wider range of operation with the 3-hole injectors. Minimum operational boost levels were approximately 5''Hg lower and the minimum pilot quantity that the engine would operate on was roughly cut in half. (3) A successful concept demonstration of engine lube oil pilot injection was performed where the minimum operational boost was reduced by another 5''Hg to a boost level of 3''Hg; this is, depending on altitude, in the range of boost levels of many blower and piston scavenged low BMEP engines. (4) Micropilot ignition compares very favorably to other ignitions systems. The performance of micropilot ignition with mechanical gas admission valves is very similar to the performance of precombustion chamber ignition with high pressure fuel injection. Compared to spark ignition with mechanical gas admission valves the lean limit of operation is extended by about 5''Hg. These laboratory results will be enhanced, demonstrated and commercialized by others, with management and support from CSU, during Phase III of the Micropilot Ignition program.

  10. Influence of fuel variables on the operation of automotive open and pre-chamber diesel and spark ignited stratified charge engines: a literature study covering petroleum and syncrude derived fuels, executive summary

    SciTech Connect (OSTI)

    Needham, J.R.

    1980-09-01

    A literature study was carried out to ascertain the influence of fuels and fuel variables on the operation of automotive diesel and spark ignited stratified charge engines with a view to understanding the impact of future fuels derived from syncrude. The findings from the search were presented and discussed in detail in the main report (Ricardo DP.81/539). In this executive summary, the conclusions and recommendations from the main report are presented.

  11. Ignitability testing for core drilling system. Final report

    SciTech Connect (OSTI)

    Cashdollar, K.L.; Furno, A.; Green, G.M.; Thomas, R.A.; Witwer, K.S.

    1995-06-15

    As part of a study of the hazards of the inspection of nuclear waste material stored at the Hanford, WA site, the Department of Energy (DOE) and Westinghouse Hanford Company (WHC) have developed a core drilling system to sample the material in large waste storage tanks. In support of this work, the US Bureau of Mines has studied the probability of ignition while core drilling into simulated salt cake that was permeated with a flammable gas mixture. No ignitions were observed while core drilling into the saltcake with or without a purge gas and no ignitions were observed while drilling into a steel plate.

  12. Status Of The National Ignition Campaign And National Ignition Facility Integrated Computer Control System

    SciTech Connect (OSTI)

    Lagin, L; Brunton, G; Carey, R; Demaret, R; Fisher, J; Fishler, B; Ludwigsen, P; Marshall, C; Reed, R; Shelton, R; Townsend, S

    2011-03-18

    The National Ignition Facility (NIF) at the Lawrence Livermore National Laboratory is a stadium-sized facility that will contains a 192-beam, 1.8-Megajoule, 500-Terawatt, ultraviolet laser system together with a 10-meter diameter target chamber with room for multiple experimental diagnostics. NIF is the world's largest and most energetic laser experimental system, providing a scientific center to study inertial confinement fusion (ICF) and matter at extreme energy densities and pressures. NIF's laser beams are designed to compress fusion targets to conditions required for thermonuclear burn. NIF is operated by the Integrated Computer Control System (ICCS) in an object-oriented, CORBA-based system distributed among over 1800 frontend processors, embedded controllers and supervisory servers. In the fall of 2010, a set of experiments began with deuterium and tritium filled targets as part of the National Ignition Campaign (NIC). At present, all 192 laser beams routinely fire to target chamber center to conduct fusion and high energy density experiments. During the past year, the control system was expanded to include automation of cryogenic target system and over 20 diagnostic systems to support fusion experiments were deployed and utilized in experiments in the past year. This talk discusses the current status of the NIC and the plan for controls and information systems to support these experiments on the path to ignition.

  13. Enhanced ignition for I. C. engines with premixed gases

    SciTech Connect (OSTI)

    Dale, J.D.; Oppenheim, A.K.

    1981-01-01

    The development of lean charge, fast burn engines depends crucially on enhanced ignition. Enhanced ignition involves not only high energies and long duration of ignition, but also a wide dispersion of its sources, so that combustion is carried out at as many sites throughout the charge as possible. Upon this premise, various ignition systems for I.C. engines, operating with premixed charge, are reviewed. The systems are grouped as follows: high energy spark plugs; plasma jet igniters; photochemical, laser, and microwave ignition concepts; torch cells; divided chamber stratified charge engines; flame jet igniters; combustion jet ignition concepts; EGR ignition system. The first three derive the power from electrical energy, the rest are powered by exothermic chemical reactions. The review emphasizes the concept of staging the processes of initiation and propagation of combustion. Relative positions of various ignition systems are expressed on the plane of relative energies (the ratio of energy consumed by the ignition system, or contained in a pre-chamber, to that of the compressed charge in the main chamber) and relative volumes (the ratio of the volume of the pre-chamber to that of the compressed charge). In principle, ignition systems for engines operating with premixed charge lie on the half-plane of relative energies below one, between 10/sup -5/ for standard spark plugs to 10/sup -1/ for divided chamber stratified charge engines, while their relative volumes extend from 0 for spark igniters to 0.2 for stratified charge engines. This suggests that proper compartmentization of the combustion process may lead to significant improvements in both pollution emissions from the cylinder and specific fuel consumption of I.C. engines.

  14. Detailed Chemical Kinetic Reaction Mechanisms for Primary Reference Fuels for Diesel Cetane Number and Spark-Ignition Octane Number

    SciTech Connect (OSTI)

    Westbrook, C K; Pitz, W J; Mehl, M; Curran, H J

    2010-03-03

    For the first time, a detailed chemical kinetic reaction mechanism is developed for primary reference fuel mixtures of n-hexadecane and 2,2,4,4,6,8,8-heptamethyl nonane for diesel cetane ratings. The mechanisms are constructed using existing rules for reaction pathways and rate expressions developed previously for the primary reference fuels for gasoline octane ratings, n-heptane and iso-octane. These reaction mechanisms are validated by comparisons between computed and experimental results for shock tube ignition and for oxidation under jet-stirred reactor conditions. The combined kinetic reaction mechanism contains the submechanisms for the primary reference fuels for diesel cetane ratings and submechanisms for the primary reference fuels for gasoline octane ratings, all in one integrated large kinetic reaction mechanism. Representative applications of this mechanism to two test problems are presented, one describing fuel/air autoignition variations with changes in fuel cetane numbers, and the other describing fuel combustion in a jet-stirred reactor environment with the fuel varying from pure 2,2,4,4,6,8,8-heptamethyl nonane (Cetane number of 15) to pure n-hexadecane (Cetane number of 100). The final reaction mechanism for the primary reference fuels for diesel fuel and gasoline is available on the web.

  15. Experimental Investigation of Spark-Ignited Combustion with High-Octane Biofuels and EGR. 1. Engine Load Range and Downsize Downspeed Opportunity

    SciTech Connect (OSTI)

    Splitter, Derek A; Szybist, James P

    2013-01-01

    The present study experimentally investigates spark-ignited combustion with 87 AKI E0 gasoline in its neat form and in midlevel alcohol gasoline blends with 24% vol/vol isobutanol gasoline (IB24) and 30% vol/vol ethanol gasoline (E30). A single-cylinder research engine was used with an 11.85:1 compression ratio, hydraulically actuated valves, laboratory intake air, and was capable of external exhaust gas recirculation (EGR). Experiments were conducted with all fuels to full-load conditions with = 1, using both 0% and 15% external cooled EGR. Higher octane number biofuel blends exhibited increased stoichiometric torque capability at this compression ratio, where the unique properties of ethanol enabled a doubling of the stoichiometric torque capability with E30 as compared to 87 AKI, up to 20 bar IMEPg (indicated mean effective pressure gross) at = 1. EGR provided thermodynamic advantages and was a key enabler for increasing engine efficiency for all fuel types. However, with E30, EGR was less useful for knock mitigation than gasoline or IB24. Torque densities with E30 with 15% EGR at = 1 operation were similar or better than a modern EURO IV calibration turbo-diesel engine. The results of the present study suggest that it could be possible to implement a 40% downsize + downspeed configuration (1.2 L engine) into a representative midsize sedan. For example, for a midsize sedan at a 65 miles/h cruise, an estimated fuel consumption of 43.9 miles per gallon (MPG) (engine out 102 g-CO2/km) could be achieved with similar reserve power to a 2.0 L engine with 87AKI (38.6 MPG, engine out 135 g-CO2/km). Data suggest that, with midlevel alcohol gasoline blends, engine and vehicle optimization can offset the reduced fuel energy content of alcohol gasoline blends and likely reduce vehicle fuel consumption and tailpipe CO2 emissions.

  16. Enhanced ignition for I. C. engines with premixed charge

    SciTech Connect (OSTI)

    Dale, J.D.; Oppenheim, A.K.

    1980-10-01

    The development of lean charge, fast burn engines depends crucially on enhanced ignition, since one can obtain thereby proper means for increasing the rate of burn in mixtures characterized notoriously by low normal burning speeds. Enhanced ignition involves a wide dispersion of its sources so that combustion is carried out at as many sites throughout the charge as possible. Upon this premise, various ignition systems for I.C. engines, operating with premixed charge, are reviewed. The systems are grouped within the following categories: (1) high energy spark plugs; (2) plasma jet igniters; (3) photochemical, laser, and microwave ignition concepts; (4) torch cells; (5) divided chamber stratified charge engines; (6) flame jet igniters; (7) combustion jet ignition concepts; (8) EGR ignition system. The first three derive the power from electrical energy, the rest are powered by exothermic chemical reactions at a significantly lower, practically negligible, fuel consumption. The concept of staging the processes of initiation and propagation of combustion is emphasized. Relative positions of various ignition systems are expressed on the plane of relative energies and relative volumes. In principle, ignition systems for engines operating with premixed charge lie on the half-plane of relative energies below one, between 10/sup -5/ for standard spark plugs to 10/sup -1/ for divided chamber stratified charge engines, while their relative volumes extend from 0 for spark igniters to 0.2 for stratified charge engines. This suggests that proper compartmentization of the combustion process may lead to significant improvements in both pollution emissions from the cylinder and specific fuel consumption of I.C. engines.

  17. Experimental Investigation of Spark-Ignited Combustion with High-Octane Biofuels and EGR. 2. Fuel and EGR Effects on Knock-Limited Load and Speed

    SciTech Connect (OSTI)

    Splitter, Derek A; Szybist, James P

    2013-01-01

    The present study experimentally investigates spark-ignited combustion with 87 AKI E0 gasoline in its neat form and in midlevel alcohol gasoline blends with 24% vol/vol isobutanol gasoline (IB24) and 30% vol/vol ethanol gasoline (E30). A single-cylinder research engine is used with an 11.85:1 compression ratio, hydraulically actuated valves, laboratory intake air, and was capable of external exhaust gas recirculation (EGR). Experiments were conducted with all fuels to full-load conditions with = 1, using both 0% and 15% external-cooled EGR. Higher octane number biofuel blends exhibited increased stoichiometric torque capability at this compression ratio, where the unique properties of ethanol enabled a doubling of the stoichiometric torque capability with E30 as compared to that of 87AKI, up to 20 bar IMEPg (indicating mean effective pressure gross) at = 1. The results demonstrate that for all fuels, EGR is a key enabler for increasing engine efficiency but is less useful for knock mitigation with E30 than for 87AKI gasoline or IB24. Under knocking conditions, 15% EGR is found to offer 1 CA of CA50 timing advance with E30, whereas up to 5 CA of CA50 advance is possible with knock-limited 87AKI gasoline. Compared to 87AKI, both E30 and IB24 are found to have reduced adiabatic flame temperature and shorter combustion durations, which reduce knocking propensity beyond that indicated by the octane number. However, E30+0% EGR is found to exhibit the better antiknock properties than either 87AKI+15% EGR or IB24+15% EGR, expanding the knock limited operating range and engine stoichiometric torque capability at high compression ratio. Furthermore, the fuel sensitivity (S) of E30 was attributed to reduced speed sensitivity of E30, expanding the low-speed stoichiometric torque capability at high compression ratio. The results illustrate that intermediate alcohol gasoline blends exhibit exceptional antiknock properties and performance beyond that indicated by the octane number tests, particularly E30.

  18. Emissions and fuel economy of a vehicle with a spark-ignition, direct-injection engine : Mitsubishi Legnum GDI{trademark}.

    SciTech Connect (OSTI)

    Cole, R. L.; Poola, R. B.; Sekar, R.

    1999-04-08

    A 1997 Mitsubishi Legnum station wagon with a 150-hp, 1.8-L, spark-ignition, direct-injection (SIDI) engine was tested for emissions by using the FTP-75, HWFET, SC03, and US06 test cycles and four different fuels. The purpose of the tests was to obtain fuel-economy and emissions data on SIDI vehicles and to compare the measurements obtained with those of a port-fuel-injection (PFI) vehicle. The PFI vehicle chosen for the comparison was a 1995 Dodge Neon, which meets the Partnership for a New Generation of Vehicles (PNGV) emissions goals of nonmethane hydrocarbons (NMHC) less than 0.125 g/mi, carbon monoxide (CO) less than 1.7 g/mi, nitrogen oxides (NO{sub x} ) less than 0.2 g/mi, and particulate matter (PM) less than 0.01 g/mi. The Mitsubishi was manufactured for sale in Japan and was not certified to meet current US emissions regulations. Results show that the SIDI vehicle can provide up to 24% better fuel economy than the PFI vehicle does, with correspondingly lower greenhouse gas emissions. The SIDI vehicle as designed does not meet the PNGV goals for NMHC or NO{sub x} emissions, but it does meet the goal for CO emissions. Meeting the goal for PM emissions appears to be contingent upon using low-sulfur fuel and an oxidation catalyst. One reason for the difficulty in meeting the NMHC and NO{sub x} goals is the slow (200 s) warm-up of the catalyst. Catalyst warm-up time is primarily a matter of design. The SIDI engine produces more NMHC and NO{sub x} than the PFI engine does, which puts a greater burden on the catalyst to meet the emissions goals than is the case with the PFI engine. Oxidation of NMHC is aided by unconsumed oxygen in the exhaust when the SIDI engine operates in stratified-charge mode, but the same unconsumed oxygen inhibits chemical reduction of NO{sub x} . Thus, meeting the NO{sub x} emissions goal is likely to be the greatest challenge for the SIDI engine.

  19. Rotary engine with dual spark plugs and fuel injectors

    SciTech Connect (OSTI)

    Abraham, J.; Bracco, F.V.

    1991-06-11

    This patent describes a stratified charge rotary combustion engine having a housing having a running surface surrounding a working chamber, the running surface having a two-lobed profile, the lobes forming a junction in a top-dead-center region of the housing, a rotor mounted for rotation in the working chamber, a fuel injection and ignition system placed in the top-dead center region. It includes a pilot fuel injector fuel into the working chamber; a first spark plug located upstream of the pilot fuel injector for igniting fuel injected by the pilot fuel injector, the pilot fuel injector and the first spark plug being located on a downstream side of the junction; a main fuel injector for injecting fuel into the working chamber, the ignited pilot fuel acting to ignite fuel injected by the main injector; and a second spark plug located upstream of the main fuel injector and located upstream of the junction for igniting fuel/air mixture in the working chamber.

  20. The Neutron Imaging System Fielded at the National Ignition Facility

    SciTech Connect (OSTI)

    Fittinghoff, D N; Atkinson, D P; Bower, D E; Drury, O B; Dzenitis, J M; Felker, B; Frank, M; Liddick, S N; Moran, M J; Roberson, G P; Weiss, P B; Grim, G P; Aragonez, R J; Archuleta, T N; Batha, S H; Clark, D D; Clark, D J; Danly, C R; Day, R D; Fatherley, V E; Finch, J P; Garcia, F P; Gallegos, R A; Guler, N; Hsu, A H; Jaramillo, S A; Loomis, E N; Mares, D; Martinson, D D; Merrill, F E; Morgan, G L; Munson, C; Murphy, T J; Oertel, J A; Polk, P J; Schmidt, D W; Tregillis, I L; Valdez, A C; Volegov, P L; Wang, T F; Wilde, C H; Wilke, M D; Wilson, D C; Buckles, R A; Cradick, J R; Kaufman, M I; Lutz, S S; Malone, R M; Traille, A

    2011-10-24

    We have fielded a neutron imaging system at the National Ignition Facility to collect images of fusion neutrons produced in the implosion of inertial confinement fusion experiments and scattered neutrons from (n, n') reactions of the source neutrons in the surrounding dense material. A description of the neutron imaging system will be presented, including the pinhole array aperture, the line-of-sight collimation, the scintillator-based detection system and the alignment systems and methods. Discussion of the alignment and resolution of the system will be presented. We will also discuss future improvements to the system hardware.

  1. Spark Spread

    Gasoline and Diesel Fuel Update (EIA)

    Spark Spread Figure 1 Source: U.S. Energy Information Administration, based on SNL Energy. The spark spread is a common metric for estimating the profitability of natural gas-fired electric generators. The spark spread is the difference between the price received by a generator for electricity produced and the cost of the natural gas needed to produce that electricity. It is typically calculated using daily spot prices for natural gas and power at various regional trading points. The chart above

  2. The Neutron Imaging System Fielded at the National Ignition Facility

    SciTech Connect (OSTI)

    Merrill, F E; Buckles, R; Clark, D D; Danly, C R; Drury, O B; Dzenitis, J M; Fatherley, V E; Fittinghoff, D N; Gallegos, R; Grim, G P; Guler, N; Loomis, E N; Lutz, S; Malone, R M; Martinson, D D; Mares, D; Morley, D J; Morgan, G L; Oertel, J A; Tregillis, I L; Volegov, P L; Weiss, P B; Wilde, C H

    2012-08-01

    A neutron imaging diagnostic has recently been commissioned at the National Ignition Facility (NIF). This new system is an important diagnostic tool for inertial fusion studies at the NIF for measuring the size and shape of the burning DT plasma during the ignition stage of Inertial Confinement Fusion (ICF) implosions. The imaging technique utilizes a pinhole neutron aperture, placed between the neutron source and a neutron detector. The detection system measures the two dimensional distribution of neutrons passing through the pinhole. This diagnostic has been designed to collect two images at two times. The long flight path for this diagnostic, 28 m, results in a chromatic separation of the neutrons, allowing the independently timed images to measure the source distribution for two neutron energies. Typically the first image measures the distribution of the 14 MeV neutrons and the second image of the 6-12 MeV neutrons. The combination of these two images has provided data on the size and shape of the burning plasma within the compressed capsule, as well as a measure of the quantity and spatial distribution of the cold fuel surrounding this core.

  3. Target diagnostic system for the national ignition facility (invited)

    SciTech Connect (OSTI)

    Leeper, R.J.; Chandler, G.A.; Cooper, G.W.; Derzon, M.S.; Fehl, D.L.; Hebron, D.E.; Moats, A.R.; Noack, D.D.; Porter, J.L.; Ruggles, L.E.; Ruiz, C.L.; Torres, J.A.; Cable, M.D.; Bell, P.M.; Clower, C.A.; Hammel, B.A.; Kalantar, D.H.; Karpenko, V.P.; Kauffman, R.L.; Kilkenny, J.D.; Lee, F.D.; Lerche, R.A.; MacGowan, B.J.; Moran, M.J.; Nelson, M.B.; Olson, W.; Orzechowski, T.J.; Phillips, T.W.; Ress, D.; Tietbohl, G.L.; Trebes, J.E.; Bartlett, R.J.; Berggren, R.; Caldwell, S.E.; Chrien, R.E.; Failor, B.H.; Fernandez, J.C.; Hauer, A.; Idzorek, G.; Hockaday, R.G.; Murphy, T.J.; Oertel, J.; Watt, R.; Wilke, M.; Bradley, D.K.; Knauer, J.; Petrasso, R.D.; Li, C.K.

    1997-01-01

    A review of recent progress on the design of a diagnostic system proposed for ignition target experiments on the National Ignition Facility (NIF) will be presented. This diagnostic package contains an extensive suite of optical, x ray, gamma ray, and neutron diagnostics that enable measurements of the performance of both direct and indirect driven NIF targets. The philosophy used in designing all of the diagnostics in the set has emphasized redundant and independent measurement of fundamental physical quantities relevant to the operation of the NIF target. A unique feature of these diagnostics is that they are being designed to be capable of operating in the high radiation, electromagnetic pulse, and debris backgrounds expected on the NIF facility. The diagnostic system proposed can be categorized into three broad areas: laser characterization, hohlraum characterization, and capsule performance diagnostics. The operating principles of a representative instrument from each class of diagnostic employed in this package will be summarized and illustrated with data obtained in recent prototype diagnostic tests. {copyright} {ital 1997 American Institute of Physics.}

  4. Methanol with dimethyl ether ignition promotor as fuel for compression ignition engines

    SciTech Connect (OSTI)

    Brook, D.L.; Cipolat, D.; Rallis, C.J.

    1984-08-01

    Reduction of the world dependence upon crude oil necessitates the use of long term alternative fuels for internal combustion engines. Alcohols appear to offer a solution as in the short term they can be manufactured from natural gas and coal, while ultimately they may be produced from agricultural products. A fair measure of success has been achieved in using alcohols in spark ignition engines. However the more widely used compression ignition engines cannot utilize unmodified pure alcohols. The current techniques for using alcohol fuels in compression ignition engines all have a number of shortcomings. This paper describes a novel technique where an ignition promotor, dimethyl ether (DME), is used to increase the cetane rating of methanol. The systems particular advantage is that the DME can be catalyzed from the methanol base fuel, in situ. This fuel system matches the performance characteristics of diesel oil fuel.

  5. A photographic study of fuel spray ignition in a rapid compression machine

    SciTech Connect (OSTI)

    Solomon, A.S.P.

    1986-01-01

    The process of spark ignition of fuel sprays in a rapid compression machine was analyzed using high-speed schlieren photography and pressure-time data. The combustion chamber studied simulates in a two-dimensional sense the three-dimensional arrangement of the piston bowl, injector and spark plug in a typical direct-injection stratified-charge (DISC) engine. The test hardware included a flat-seat straight-hole injector, a high-energy ignition system and an extended-electrode spark plug. The influence of amount of fuel injected, ignition dwell period (time between start of injection and start of ignition), swirl rate and direction, and spark-plug electrode-tip location on the ignition process was examined. For the test conditions studied, excessive spray penetration and fuel impingement on the walls was observed. The ignition process was observed to be governed by the delayed formation, growth and transport of a flame kernel which spreads to complete the major portion of the burn only after the injection process has been completed. The factors found to influence the evolution of the flame kernel could be possible mechanisms for the high cyclic variability and high hydrocarbon emissions observed for DISC engines of the type simulated.

  6. HYDROGEN IGNITION MECHANISM FOR EXPLOSIONS IN NUCLEAR FACILITY PIPE SYSTEMS

    SciTech Connect (OSTI)

    Leishear, R

    2010-05-02

    Hydrogen and oxygen generation due to the radiolysis of water is a recognized hazard in pipe systems used in the nuclear industry, where the accumulation of hydrogen and oxygen at high points in the pipe system is expected, and explosive conditions exist. Pipe ruptures at nuclear facilities were attributed to hydrogen explosions inside pipelines, in nuclear facilities, i.e., Hamaoka, Nuclear Power Station in Japan, and Brunsbuettel in Germany. Prior to these accidents an ignition source for hydrogen was questionable, but these accidents, demonstrated that a mechanism was, in fact, available to initiate combustion and explosion. Hydrogen explosions may occur simultaneously with water hammer accidents in nuclear facilities, and a theoretical mechanism to relate water hammer to hydrogen deflagrations and explosions is presented herein.

  7. Final Scientific and Technical Report - Practical Fiber Delivered Laser Ignition Systems for Vehicles

    SciTech Connect (OSTI)

    Yalin, Azer

    2014-03-30

    Research has characterized advanced kagome fiber optics for their use in laser ignition systems. In comparison to past fibers used in laser ignition, these fibers have the important advantage of being relatively bend-insensitivity, so that they can be bent and coiled without degradation of output energy or beam quality. The results are very promising for practical systems. For pulse durations of ~12 ns, the fibers could deliver >~10 mJ pulses before damage onset. A study of pulse duration showed that by using longer pulse duration (~20 – 30 ns), it is possible to carry even higher pulse energy (by factor of ~2-3) which also provides future opportunities to implement longer duration sources. Beam quality measurements showed nearly single-mode output from the kagome fibers (i.e. M2 close to 1) which is the optimum possible value and, combined with their high pulse energy, shows the suitability of the fibers for laser ignition. Research has also demonstrated laser ignition of an engine including reliable (100%) ignition of a single-cylinder gasoline engine using the laser ignition system with bent and coiled kagome fiber. The COV of IMEP was <2% which is favorable for stable engine operation. These research results, along with the continued reduction in cost of laser sources, support our commercial development of practical laser ignition systems.

  8. THE ODTX SYSTEM FOR THERMAL IGNITION AND THERMAL SAFETY STUDY OF ENERGETIC MATERIALS

    SciTech Connect (OSTI)

    Hsu, P C; Hust, G; Howard, M; Maienschein, J L

    2010-03-03

    Understanding the response of energetic material to thermal event is very important for the storage and handling of energetic materials. The One Dimensional Time to Explosion (ODTX) system at the Lawrence Livermore National Laboratory (LLNL) can precisely measure times to explosion and minimum ignition temperatures of energetic materials at elevated temperatures. These measurements provide insight into the relative ease of thermal ignition and allow for the determination of kinetic parameters. The ODTX system can potentialy be a good tool to measure violence of the thermal ignition by monitoring the size of anvil cavity. Recent ODTX experimental data on various energetic materials (solid and liquids) are reported in this paper.

  9. Large eddy simulation of forced ignition of an annular bluff-body burner

    SciTech Connect (OSTI)

    Subramanian, V.; Domingo, P.; Vervisch, L.

    2010-03-15

    The optimization of the ignition process is a crucial issue in the design of many combustion systems. Large eddy simulation (LES) of a conical shaped bluff-body turbulent nonpremixed burner has been performed to study the impact of spark location on ignition success. This burner was experimentally investigated by Ahmed et al. [Combust. Flame 151 (2007) 366-385]. The present work focuses on the case without swirl, for which detailed measurements are available. First, cold-flow measurements of velocities and mixture fractions are compared with their LES counterparts, to assess the prediction capabilities of simulations in terms of flow and turbulent mixing. Time histories of velocities and mixture fractions are recorded at selected spots, to probe the resolved probability density function (pdf) of flow variables, in an attempt to reproduce, from the knowledge of LES-resolved instantaneous flow conditions, the experimentally observed reasons for success or failure of spark ignition. A flammability map is also constructed from the resolved mixture fraction pdf and compared with its experimental counterpart. LES of forced ignition is then performed using flamelet fully detailed tabulated chemistry combined with presumed pdfs. Various scenarios of flame kernel development are analyzed and correlated with typical flow conditions observed in this burner. The correlations between, velocities and mixture fraction values at the sparking time and the success or failure of ignition, are then further discussed and analyzed. (author)

  10. Laser ignition

    DOE Patents [OSTI]

    Early, James W. (Los Alamos, NM); Lester, Charles S. (San Juan Pueblo, NM)

    2002-01-01

    In the apparatus of the invention, a first excitation laser or other excitation light source capable of producing alternating beams of light having different wavelengths is used in tandem with one or more ignitor lasers to provide a compact, durable, engine deployable fuel ignition laser system. Reliable fuel ignition is provided over a wide range of fuel conditions by using the single remote excitation light source for pumping one or more small lasers located proximate to one or more fuel combustion zones with alternating wavelengths of light.

  11. Laser ignition

    DOE Patents [OSTI]

    Early, James W. (Los Alamos, NM); Lester, Charles S. (San Juan Pueblo, NM)

    2002-01-01

    In the apparatus of the invention, a first excitation laser or other excitation light source is used in tandem with an ignitor laser to provide a compact, durable, engine deployable fuel ignition laser system. The beam from the excitation light source is split with a portion of it going to the ignitor laser and a second portion of it being recombined with the first portion after a delay before injection into the ignitor laser. Reliable fuel ignition is provided over a wide range of fuel conditions by using a single remote excitation light source for one or more small lasers located proximate to one or more fuel combustion zones.

  12. Distributed ignition method and apparatus for a combustion engine

    DOE Patents [OSTI]

    Willi, Martin L.; Bailey, Brett M.; Fiveland, Scott B.; Gong, Weidong

    2006-03-07

    A method and apparatus for operating an internal combustion engine is provided. The method comprises the steps of introducing a primary fuel into a main combustion chamber of the engine, introducing a pilot fuel into the main combustion chamber of the engine, determining an operating load of the engine, determining a desired spark plug ignition timing based on the engine operating load, and igniting the primary fuel and pilot fuel with a spark plug at the desired spark plug ignition timing. The method is characterized in that the octane number of the pilot fuel is lower than the octane number of the primary fuel.

  13. Fast Ignition

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Fast Ignition Researchers Study Fast Ignition University of California at San Diego researchers participate in experiments on the Titan laser at LLNL's Jupiter Laser Facility to study fast ignition. The approach being taken by the National Ignition Facility to achieve thermonuclear ignition and burn is called the "central hot spot" scenario. This technique relies on simultaneous compression and ignition of a spherical fuel capsule in an implosion, roughly like in a diesel engine (see

  14. A HYDROGEN IGNITION MECHANISM FOR EXPLOSIONS IN NUCLEAR FACILITY PIPING SYSTEMS

    SciTech Connect (OSTI)

    Leishear, R.

    2013-03-28

    Hydrogen explosions may occur simultaneously with water hammer accidents in nuclear facilities, and a theoretical mechanism to relate water hammer to hydrogen deflagrations and explosions is presented herein. Hydrogen and oxygen generation due to the radiolysis of water is a recognized hazard in pipe systems used in the nuclear industry, where the accumulation of hydrogen and oxygen at high points in the pipe system is expected, and explosive conditions may occur. Pipe ruptures in nuclear reactor cooling systems were attributed to hydrogen explosions inside pipelines, i.e., Hamaoka, Nuclear Power Station in Japan, and Brunsbuettel in Germany. Prior to these accidents, an ignition source for hydrogen was not clearly demonstrated, but these accidents demonstrated that a mechanism was, in fact, available to initiate combustion and explosion. A new theory to identify an ignition source and explosion cause is presented here, and further research is recommended to fully understand this explosion mechanism.

  15. IMPROVEMENT TO PIPELINE COMPRESSOR ENGINE RELIABILITY THROUGH RETROFIT MICRO-PILOT IGNITION SYSTEM -- PHASE III

    SciTech Connect (OSTI)

    Scott Chase; Daniel Olsen; Ted Bestor

    2005-03-01

    This report documents the third year's effort towards a 3-year program conducted by the Engines & Energy Conversion Laboratory (EECL) at Colorado State University (CSU) to develop micropilot ignition systems for existing pipeline compressor engines. Research activities for the overall program were conducted with the understanding that the efforts are to result in a commercial product to capture and disseminate the efficiency and environmental benefits of this new technology. Commercially-available fuel injection products were identified and applied to the program where appropriate. This approach will minimize the overall time-to-market requirements, while meeting performance and cost criteria. Two earlier phases of development precede this report. The objective for Phase I was to demonstrate the feasibility of retrofit micropilot ignition (RMI) systems for large bore, slow speed engines operating at low compression ratios under laboratory conditions at the EECL. The objective for Phase II was to further develop and optimize the micropilot ignition system at the EECL for large bore, slow speed engines operating at low compression ratios. These laboratory results were enhanced, then verified via a field demonstration project during Phase III of the Micropilot Ignition program. An Implementation Team of qualified engine retrofit service providers was assembled to install the retrofit micropilot ignition system for an engine operated by El Paso Pipeline Group at a compressor station near Window Rock, Arizona. Testing of this demonstration unit showed that the same benefits identified by laboratory testing at CSU, i.e., reduced fuel consumption and exhaust emissions (NOx, THC, CO, and CH2O). Installation efforts at Window Rock were completed towards the end of the budget period, which did not leave sufficient time to complete the durability testing. These efforts are ongoing, with funding provided by El Paso Pipeline Group, and the results will be documented in a report. Commercialization of the retrofit micropilot ignition (RMI) technology is awaiting a ''market pull'', which is expected to materialize as the results of the field demonstration become known and accepted. The Implementation Team, comprised of Woodward Governor Company, Enginuity LLC, Hoerbiger Corporation of America, and DigiCon Inc., has direct experience with the technology development and implementation, and stands ready to promote and commercialize the RMI system.

  16. Pulse-actuated fuel-injection spark plug

    DOE Patents [OSTI]

    Murray, Ian; Tatro, Clement A.

    1978-01-01

    A replacement spark plug for reciprocating internal combustion engines that functions as a fuel injector and as a spark plug to provide a "stratified-charge" effect. The conventional carburetor is retained to supply the main fuel-air mixture which may be very lean because of the stratified charge. The replacement plug includes a cylindrical piezoelectric ceramic which contracts to act as a pump whenever an ignition pulse is applied to a central rod through the ceramic. The rod is hollow at its upper end for receiving fuel, it is tapered along its lower length to act as a pump, and it is flattened at its lower end to act as a valve for fuel injection from the pump into the cylinder. The rod also acts as the center electrode of the plug, with the spark jumping from the plug base to the lower end of the rod to thereby provide spark ignition that has inherent proper timing with the fuel injection.

  17. Spark Distributed Analytic Framework

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    To connect to the Scala Spark Shell, do: spark-shell --master SPARKURL --driver-memory 15G --executor-memory 20G The --driver-memory flag sets how much of the 128 GB (64 GB...

  18. ITP Industrial Distributed Energy: CHP and Bioenergy Systems for Landfills and Wastewater Treatment Plants

    Office of Energy Efficiency and Renewable Energy (EERE) Indexed Site

    Systems for Landfills and Wastewater Treatment Plants November 7, 2007 Denver, Colorado Paul Lemar Jr., President pll@rdcnet.com www.rdcnet.com www.distributed-generation.com Reciprocating Engines for ADG and LFG z Reciprocating engines are either Otto (spark ignition) or Diesel (compression ignition) cycle systems z Natural gas engines, as well as those powered by ADG or LFG, are typically spark ignition systems z Some dual fuel engines have been developed using ADG/LFG with a portion of diesel

  19. Laser ignition

    DOE Patents [OSTI]

    Early, James W. (Los Alamos, NM); Lester, Charles S. (San Juan Pueblo, NM)

    2002-01-01

    In the apparatus of the invention, a first excitation laser or other excitation light source is used in tandem with an ignitor laser to provide a compact, durable, engine deployable fuel ignition laser system. Reliable fuel ignition is provided over a wide range of fuel conditions by using a single remote excitation light source for one or more small lasers located proximate to one or more fuel combustion zones. In the embodiment of the invention claimed herein, the beam from the excitation light source is split with a portion of it going to the ignitor laser and a second portion of it being combined with either the first portion after a delay before injection into the ignitor laser.

  20. Laser ignition

    DOE Patents [OSTI]

    Early, James W. (Los Alamos, NM); Lester, Charles S. (San Juan Pueblo, NM)

    2003-01-01

    In the apparatus of the invention, a first excitation laser or other excitation light source is used in tandem with an ignitor laser to provide a compact, durable, engine deployable fuel ignition laser system. Reliable fuel ignition is provided over a wide range of fuel conditions by using a single remote excitation light source for one or more small lasers located proximate to one or more fuel combustion zones. In a third embodiment, alternating short and long pulses of light from the excitation light source are directed into the ignitor laser. Each of the embodiments of the invention can be multiplexed so as to provide laser light energy sequentially to more than one ignitor laser.

  1. Rotating arc spark plug

    DOE Patents [OSTI]

    Whealton, John H.; Tsai, Chin-Chi

    2003-05-27

    A spark plug device includes a structure for modification of an arc, the modification including arc rotation. The spark plug can be used in a combustion engine to reduce emissions and/or improve fuel economy. A method for operating a spark plug and a combustion engine having the spark plug device includes the step of modifying an arc, the modifying including rotating the arc.

  2. US Department of Energy - Office of FreedomCar and Vehicle Technologies and US Centers for Disease Control and Prevention - National Institute for Occupational Safety and Health Inter-Agency Agreement Research on "The Analysis of Genotoxic Activities of Exhaust Emissions from Mobile Natural Gas, Diesel, and Spark-Ignition Engines"

    SciTech Connect (OSTI)

    William E. Wallace

    2006-09-30

    The US Department of Energy-Office of Heavy Vehicle Technologies (now the DOE-Office of FreedomCar and Vehicle Technologies) signed an Interagency Agreement (IAA) with National Institute for Occupational Safety and Health (NIOSH), No.01-15 DOE, 9/4/01, for 'The analysis of genotoxic activities of exhaust emissions from mobile natural gas, diesel, and spark-ignition engines'; subsequently modified on 3/27/02 (DOE IAG No.01-15-02M1); subsequently modified 9/02/03 (IAA Mod No. 01-15-03M1), as 'The analysis of genotoxic activities of exhaust emissions from mobile internal combustion engines: identification of engine design and operational parameters controlling exhaust genotoxicity'. The DOE Award/Contract number was DE-AI26-01CH11089. The IAA ended 9/30/06. This is the final summary technical report of National Institute for Occupational Safety and Health research performed with the US Department of Energy-Office of FreedomCar and Vehicle Technologies under that IAA: (A) NIOSH participation was requested by the DOE to provide in vitro genotoxicity assays of the organic solvent extracts of exhaust emissions from a suite of in-use diesel or spark-ignition vehicles; (B) research also was directed to develop and apply genotoxicity assays to the particulate phase of diesel exhaust, exploiting the NIOSH finding of genotoxicity expression by diesel exhaust particulate matter dispersed into the primary components of the surfactant coating the surface of the deep lung; (C) from the surfactant-dispersed DPM genotoxicity findings, the need for direct collection of DPM aerosols into surfactant for bioassay was recognized, and design and developmental testing of such samplers was initiated.

  3. design a high-resolution diagnostic system for the National Ignition

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Facility | Princeton Plasma Physics Lab design a high-resolution diagnostic system for the National Ignition Facility By John Greenwald November 16, 2015 Tweet Widget Google Plus One Share on Facebook Kenneth Hill and Manfred Bitter inspect an X-ray crystal spectrometer to be used to study OMEGA EP laser-produced plasmas. (Photo by Elle Starkman/Office of Communications) Kenneth Hill and Manfred Bitter inspect an X-ray crystal spectrometer to be used to study OMEGA EP laser-produced plasmas.

  4. Compression ignition engine having fuel system for non-sooting combustion and method

    DOE Patents [OSTI]

    Bazyn, Timothy; Gehrke, Christopher

    2014-10-28

    A direct injection compression ignition internal combustion engine includes a fuel system having a nozzle extending into a cylinder of the engine and a plurality of spray orifices formed in the nozzle. Each of the spray orifices has an inner diameter dimension of about 0.09 mm or less, and define inter-orifice angles between adjacent spray orifice center axes of about 36.degree. or greater such that spray plumes of injected fuel from each of the spray orifices combust within the cylinder according to a non-sooting lifted flame and gas entrainment combustion pattern. Related methodology is also disclosed.

  5. Initial Activation and Operation of the Power Conditioning System for the National Ignition Facility

    SciTech Connect (OSTI)

    Newton, M A; Kamm, R E; Fulkerson, E S; Hulsey, S D; Lao, N; Parrish, G L; Pendleton, D L; Petersen, D E; Polk, M; Tuck, J M; Ullery, G T; Moore, W B

    2003-08-20

    The NIF Power Conditioning System (PCS) resides in four Capacitor Bays, supplying energy to the Master and Power Amplifiers which reside in the two adjacent laser bays. Each capacitor bay will initially house 48 individual power conditioning modules, shown in Figure 2, with space reserved for expansion to 54 modules. The National Ignition Facility (NIF) Power Conditioning System (PCS) is a modular capacitive energy storage system that will be capable of storing nearly 400 MJ of electrical energy and delivering that energy to the nearly 8000 flashlamps in the NIF laser. The first sixteen modules of the power conditioning system have been built, tested and installed. Activation of the first nine power conditioning modules has been completed and commissioning of the first ''bundle'' of laser beamlines has begun. This paper will provide an overview of the power conditioning system design and describe the status and results of initial testing and activation of the first ''bundle'' of power conditioning modules.

  6. Use of the target diagnostic control system in the National Ignition Facility

    SciTech Connect (OSTI)

    Shelton, R; Lagin, L; Nelson, J

    2011-07-25

    The extreme physics of targets shocked by NIF's 192-beam laser are observed by a diverse suite of diagnostics including optical backscatter, time-integrated, time resolved and gated X-ray sensors, laser velocity interferometry, and neutron time of flight. Diagnostics to diagnose fusion ignition implosion and neutron emissions have been developed. A Diagnostic Control System (DCS) for both hardware and software facilitates development and eases integration. Each complex diagnostic typically uses an ensemble of electronic instruments attached to sensors, digitizers, cameras, and other devices. In the DCS architecture each instrument is interfaced to a low-cost Window XP processor and Java application. Instruments are aggregated as needed in the supervisory system to form an integrated diagnostic. The Java framework provides data management, control services and operator GUI generation. During the past several years, over thirty-six diagnostics have been deployed using this architecture in support of the National Ignition Campaign (NIC). The DCS architecture facilitates the expected additions and upgrades to diagnostics as more experiments are performed. This paper presents the DCS architecture, framework and our experiences in using it during the NIC to operate, upgrade and maintain a large set of diagnostic instruments.

  7. IGNITION IMPROVEMENT OF LEAN NATURAL GAS MIXTURES

    SciTech Connect (OSTI)

    Jason M. Keith

    2005-02-01

    This report describes work performed during a thirty month project which involves the production of dimethyl ether (DME) on-site for use as an ignition-improving additive in a compression-ignition natural gas engine. A single cylinder spark ignition engine was converted to compression ignition operation. The engine was then fully instrumented with a cylinder pressure transducer, crank shaft position sensor, airflow meter, natural gas mass flow sensor, and an exhaust temperature sensor. Finally, the engine was interfaced with a control system for pilot injection of DME. The engine testing is currently in progress. In addition, a one-pass process to form DME from natural gas was simulated with chemical processing software. Natural gas is reformed to synthesis gas (a mixture of hydrogen and carbon monoxide), converted into methanol, and finally to DME in three steps. Of additional benefit to the internal combustion engine, the offgas from the pilot process can be mixed with the main natural gas charge and is expected to improve engine performance. Furthermore, a one-pass pilot facility was constructed to produce 3.7 liters/hour (0.98 gallons/hour) DME from methanol in order to characterize the effluent DME solution and determine suitability for engine use. Successful production of DME led to an economic estimate of completing a full natural gas-to-DME pilot process. Additional experimental work in constructing a synthesis gas to methanol reactor is in progress. The overall recommendation from this work is that natural gas to DME is not a suitable pathway to improved natural gas engine performance. The major reasons are difficulties in handling DME for pilot injection and the large capital costs associated with DME production from natural gas.

  8. Spark-safe low-voltage detonator

    DOE Patents [OSTI]

    Lieberman, Morton L. (Albuquerque, NM)

    1989-01-01

    A column of explosive in a low-voltage detonator which makes it spark-safe ncludes an organic secondary explosive charge of HMX in the form of a thin pad disposed in a bore of a housing of the detonator in an ignition region of the explosive column and adjacent to an electrical ignition device at one end of the bore. The pad of secondary charge has an axial thickness within the range of twenty to thirty percent of its diameter. The explosive column also includes a first explosive charge of CP disposed in the housing bore in the ignition region of the explosive column next to the secondary charge pad on a side opposite from the ignition device. The first CP charge is loaded under sufficient pressure, 25 to 40 kpsi, to provide mechanical confinement of the pad of secondary charge and physical coupling thereof with the ignition device. The explosive column further includes a second explosive charge of CP disposed in the housing bore in a transition region of the explosive column next to the first CP charge on a side opposite from the pad of secondary charge. The second CP charge is loaded under sufficient pressure, about 10 kpsi, to allow occurrence of DDT. The first explosive CP charge has an axial thickness within the range of twenty to thirty percent of its diameter, whereas the second explosive CP charge contains a series of increments (nominally 4) each of which has an axial thickness-to-diameter ratio of one to two.

  9. Devices to improve the performance of a conventional two-stroke spark

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    ignition engine (Conference) | SciTech Connect Devices to improve the performance of a conventional two-stroke spark ignition engine Citation Details In-Document Search Title: Devices to improve the performance of a conventional two-stroke spark ignition engine × You are accessing a document from the Department of Energy's (DOE) SciTech Connect. This site is a product of DOE's Office of Scientific and Technical Information (OSTI) and is provided as a public service. Visit OSTI to utilize

  10. 2011 Status of the Automatic Alignment System for the National Ignition Facility

    SciTech Connect (OSTI)

    Wilhelmsen, K; Awwal, A; Burkhart, S; McGuigan, D; Kamm, V M; Leach, R; Lowe-Webb, R; Wilson, R

    2011-07-19

    Automated alignment for the National Ignition Facility (NIF) is accomplished using a large-scale parallel control system that directs 192 laser beams along the 300-m optical path. The beams are then focused down to a 50-micron spot in the middle of the target chamber. The entire process is completed in less than 50 minutes. The alignment system commands 9,000 stepping motors for highly accurate adjustment of mirrors and other optics. 41 control loops per beamline perform parallel processing services running on a LINUX cluster to analyze high-resolution images of the beams and their references. This paper describes the status the NIF automatic alignment system and the challenges encountered as NIF development has transitioned from building the laser, to becoming a research project supporting a 24 hour, 7 day laser facility. NIF is now a continuously operated system where performance monitoring is increasingly more critical for operation, maintenance, and commissioning tasks. Equipment wear and the effects of high energy neutrons from fusion experiments are issues which alter alignment efficiency and accuracy. New sensors needing automatic alignment assistance are common. System modifications to improve efficiency and accuracy are prevalent. Handling these evolving alignment and maintenance needs while minimizing the impact on NIF experiment schedule is expected to be an on-going challenge for the planned 30 year operational life of NIF.

  11. Flame Arrival Measurement By Instrumented Spark Plug or Head Gasket

    Energy Science and Technology Software Center (OSTI)

    1995-04-10

    PLUGBIN was developed to support Sandia technologies involving instrumented head gaskets and spark plugs for engine research and development. It acquires and processes measurements of flame arrival and pressure from a spark ignition. Flame arrival is determined from analog ionization-probe or visible-emission signals, and/or digitial signals from a dedicated flame arrival measurement processor. The pressure measurements are analyzed to determine the time of peak pressure and the time to burn 10 and 90 percent ofmore » the charge. Histograms are then calculated and displayed for each measurement.« less

  12. Ignition Experiments

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Ignition Experiments The goal of many NIF experiments is to create a self-sustaining "burn" of fusion fuel (the hydrogen isotopes deuterium and tritium) that produces as much or more energy than the energy required to initiate the fusion reaction-an event called ignition. In moving closer to achieving ignition, NIF researchers are fulfilling the vision of early laser pioneers who conceived of using the x rays generated by a powerful, brief laser pulse to fuse hydrogen isotopes and

  13. Advanced ignition and propulsion technology program

    SciTech Connect (OSTI)

    Oldenborg, R.; Early, J.; Lester, C.

    1998-11-01

    This is the final report of a three-year, Laboratory Directed Research and Development (LDRD) project at the Los Alamos National Laboratory (LANL). Reliable engine re-ignition plays a crucial role in enabling commercial and military aircraft to fly safely at high altitudes. This project addressed research elements critical to the optimization of laser-based igniter. The effort initially involved a collaborative research and development agreement with B.F. Goodrich Aerospace and Laser Fare, Inc. The work involved integrated experiments with theoretical modeling to provide a basic understanding of the chemistry and physics controlling the laser-induced ignition of fuel aerosols produced by turbojet engine injectors. In addition, the authors defined advanced laser igniter configurations that minimize laser packaging size, weight, complexity and power consumption. These innovative ignition concepts were shown to reliably ignite jet fuel aerosols over a broad range of fuel/air mixture and a t fuel temperatures as low as -40 deg F. The demonstrated fuel ignition performance was highly superior to that obtained by the state-of-the-art, laser-spark ignition method utilizing comparable laser energy. The authors also developed a laser-based method that effectively removes optically opaque deposits of fuel hydrocarbon combustion residues from laser window surfaces. Seven patents have been either issued or are pending that resulted from the technology developments within this project.

  14. Plasma jet ignition device

    DOE Patents [OSTI]

    McIlwain, Michael E.; Grant, Jonathan F.; Golenko, Zsolt; Wittstein, Alan D.

    1985-01-15

    An ignition device of the plasma jet type is disclosed. The device has a cylindrical cavity formed in insulating material with an electrode at one end. The other end of the cylindrical cavity is closed by a metal plate with a small orifice in the center which plate serves as a second electrode. An arc jumping between the first electrode and the orifice plate causes the formation of a highly-ionized plasma in the cavity which is ejected through the orifice into the engine cylinder area to ignite the main fuel mixture. Two improvements are disclosed to enhance the operation of the device and the length of the plasma plume. One improvement is a metal hydride ring which is inserted in the cavity next to the first electrode. During operation, the high temperature in the cavity and the highly excited nature of the plasma breaks down the metal hydride, liberating hydrogen which acts as an additional fuel to help plasma formation. A second improvement consists of a cavity insert containing a plurality of spaced, metal rings. The rings act as secondary spark gap electrodes reducing the voltage needed to maintain the initial arc in the cavity.

  15. Spark-safe low-voltage detonator

    DOE Patents [OSTI]

    Lieberman, M.L.

    1988-07-01

    A column of explosive in a low-voltage detonator which makes it spark-safe includes an organic secondary explosive charge of HMX in the form of a thin pad disposed in a bore of a housing of the detonator in an ignition region of the explosive column and adjacent to an electrical ignition device at one end of the bore. The pad of secondary charge has an axial thickness within the range of twenty to thirty percent of its diameter. The explosive column also includes a first explosive charge of CP disposed in the housing bore in the ignition region of the explosive column next to the secondary charge pad on a side opposite from the ignition device. The first CP charge is loaded under sufficient pressure, 25 to 40 kpsi, to provide mechanical confinement of the pad of secondary charge and physical coupling thereof with the ignition device. The explosive column further includes a second explosive charge of CP disposed in the housing bore in a transition region of the explosive column next to the first CP charge on a side opposite from the pad of secondary charge. The second CP charge is loaded under sufficient pressure, about 10 kpsi, to allow occurrence of DDT. The first explosive CP charge has an axial thickness within the range of twenty to thirty percent of its diameter, whereas the second explosive CP charge contains a series of increments (nominally 4), each of which has an axial thickness-to-diameter ratio of one to two. 2 figs.

  16. Combustion, Control, and Fuel Effects in a Spark Assisted HCCI Engine

    Office of Scientific and Technical Information (OSTI)

    Equipped with Variable Valve Timing (Conference) | SciTech Connect Combustion, Control, and Fuel Effects in a Spark Assisted HCCI Engine Equipped with Variable Valve Timing Citation Details In-Document Search Title: Combustion, Control, and Fuel Effects in a Spark Assisted HCCI Engine Equipped with Variable Valve Timing Widespread implementation of homogeneous charge compression ignition (HCCI) engines is presently hindered by stability, control, and load range issues. Although the operable

  17. National Ignition Facility sub-system design requirements integrated timing system SSDR 1.5.3

    SciTech Connect (OSTI)

    Wiedwald, J.; Van Aersau, P.; Bliss, E.

    1996-08-26

    This System Design Requirement document establishes the performance, design, development, and test requirements for the Integrated Timing System, WBS 1.5.3 which is part of the NIF Integrated Computer Control System (ICCS). The Integrated Timing System provides all temporally-critical hardware triggers to components and equipment in other NIF systems.

  18. National Ignition Facility sub-system design requirements computer system SSDR 1.5.1

    SciTech Connect (OSTI)

    Spann, J.; VanArsdall, P.; Bliss, E.

    1996-09-05

    This System Design Requirement document establishes the performance, design, development and test requirements for the Computer System, WBS 1.5.1 which is part of the NIF Integrated Computer Control System (ICCS). This document responds directly to the requirements detailed in ICCS (WBS 1.5) which is the document directly above.

  19. Ignition and Inertial Confinement Fusion at The National Ignition Facility

    SciTech Connect (OSTI)

    Moses, E

    2009-10-01

    The National Ignition Facility (NIF), the world's largest and most powerful laser system for inertial confinement fusion (ICF) and for studying high-energy-density (HED) science, is now operational at Lawrence Livermore National Laboratory (LLNL). The NIF is now conducting experiments to commission the laser drive, the hohlraum and the capsule and to develop the infrastructure needed to begin the first ignition experiments in FY 2010. Demonstration of ignition and thermonuclear burn in the laboratory is a major NIF goal. NIF will achieve this by concentrating the energy from the 192 beams into a mm{sup 3}-sized target and igniting a deuterium-tritium mix, liberating more energy than is required to initiate the fusion reaction. NIF's ignition program is a national effort managed via the National Ignition Campaign (NIC). The NIC has two major goals: execution of DT ignition experiments starting in FY2010 with the goal of demonstrating ignition and a reliable, repeatable ignition platform by the conclusion of the NIC at the end of FY2012. The NIC will also develop the infrastructure and the processes required to operate NIF as a national user facility. The achievement of ignition at NIF will demonstrate the scientific feasibility of ICF and focus worldwide attention on laser fusion as a viable energy option. A laser fusion-based energy concept that builds on NIF, known as LIFE (Laser Inertial Fusion Energy), is currently under development. LIFE is inherently safe and can provide a global carbon-free energy generation solution in the 21st century. This paper describes recent progress on NIF, NIC, and the LIFE concept.

  20. Special Feature: Energy - The Spark that Ignited DOE Supercomputing

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Biofuels: Turning Grass into Gas If researchers can unlock the sugars stored in plant cellulose, then crops like this switchgrass could be turned into biofuels, rather than using...

  1. Advanced Lean-Burn DI Spark Ignition Fuels Research

    Broader source: Energy.gov [DOE]

    2011 DOE Hydrogen and Fuel Cells Program, and Vehicle Technologies Program Annual Merit Review and Peer Evaluation

  2. Advanced Lean-Burn DI Spark Ignition Fuels Research

    Broader source: Energy.gov [DOE]

    2012 DOE Hydrogen and Fuel Cells Program and Vehicle Technologies Program Annual Merit Review and Peer Evaluation Meeting

  3. Advanced Lean-Burn DI Spark Ignition Fuels Research

    Broader source: Energy.gov [DOE]

    2010 DOE Vehicle Technologies and Hydrogen Programs Annual Merit Review and Peer Evaluation Meeting, June 7-11, 2010 -- Washington D.C.

  4. Advanced Lean-Burn DI Spark Ignition Fuels Research

    Broader source: Energy.gov [DOE]

    2013 DOE Hydrogen and Fuel Cells Program and Vehicle Technologies Program Annual Merit Review and Peer Evaluation Meeting

  5. The Effects of Fuel Characteristics on Stoichiometric Spark-Assisted HCCI

    SciTech Connect (OSTI)

    Weall, Adam J; Szybist, James P

    2012-01-01

    The characteristics of fuel lean HCCI operation using a variety of fuels are well known and have been demonstrated using different engine concepts in the past. In contrast, stoichiometric operation of HCCI is less well documented. Recent studies have highlighted the benefits of operating at a stoichiometric condition in terms of load expansion combined with the applicability of three way catalyst technology to reduce NOx emissions. In this study the characterization of stoichiometric HCCI using gasoline-like fuels was undertaken. The fuels investigated are gasoline, a 50 vol% blend of iso-butanol and gasoline (IB50), and an 85% vol blend of ethanol and gasoline (E85). A single cylinder engine operating with direct injection and spark assist combined with a fully variable hydraulic valve actuation system allowed a wide range of operating parameters to be studied. The resultant fuel properties which differed in terms of octane rating, fuel oxygenation and heat of vaporization show that stoichiometric HCCI is possible using a range of fuels but that these fuel characteristics do have some effect on the combustion characteristics. How these fuel properties can enable an increased engine operating envelope to be achieved, in comparison with both fuel lean HCCI and conventional spark ignited combustion, is then discussed.

  6. Green Spark Ventures LLC | Open Energy Information

    Open Energy Info (EERE)

    Spark Ventures LLC Jump to: navigation, search Name: Green Spark Ventures, LLC Place: Denver, Colorado Zip: 80203 Sector: Efficiency, Renewable Energy Product: Denver-based venture...

  7. NATIONAL IGNITION FACILITY | Princeton Plasma Physics Lab

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    NATIONAL IGNITION FACILITY American Fusion News Category: National Ignition Facility Link: NATIONAL IGNITION FACILITY

  8. The Effects of Fuel Characteristics on Stoichiometric Spark-Assisted HCCI

    SciTech Connect (OSTI)

    Weall, Adam J; Szybist, James P

    2011-01-01

    The characteristics of fuel lean HCCI operation using a variety of fuels are well known and have been demonstrated using different engine concepts in the past. In contrast, stoichiometric operation of HCCI is less well documented. Recent studies have highlighted the benefits of operating at a stoichiometric condition in terms of load expansion combined with the applicability of three way catalyst technology to reduce NOx emissions. In this study the characterization of stoichiometric HCCI using gasoline-like fuels was undertaken. The fuels investigated are gasoline, a 50 vol% blend of iso-butanol and gasoline (IB50), and an 85% vol blend of ethanol and gasoline (E85). A single cylinder engine operating with direct injection and spark assist combined with a fully variable hydraulic valve actuation system allowed a wide range of operating parameters to be studied. This included the effects of negative valve overlap duration, intake valve closing and valve lift. Furthermore, the interaction between fuel injection timing and spark and how they can affect the required valve timing to achieve stoichiometric HCCI combustion are also studied. A comprehensive combustion and emissions analysis is conducted using gasoline, IB50 and E85 at an engine speed of 2000rpm over a range of operating loads. The resultant fuel properties which differed in terms of octane rating, fuel oxygenation and heat of vaporization show that stoichiometric HCCI is possible using a range of fuels but that these fuel characteristics do have some effect on the combustion characteristics. How these fuel properties can enable an increased engine operating envelope to be achieved, in comparison with both fuel lean HCCI and conventional spark ignited combustion, is then discussed.

  9. Laser ignition

    DOE Patents [OSTI]

    Early, James W.; Lester, Charles S.

    2004-01-13

    Sequenced pulses of light from an excitation laser with at least two resonator cavities with separate output couplers are directed through a light modulator and a first polarzing analyzer. A portion of the light not rejected by the first polarizing analyzer is transported through a first optical fiber into a first ignitor laser rod in an ignitor laser. Another portion of the light is rejected by the first polarizing analyzer and directed through a halfwave plate into a second polarization analyzer. A first portion of the output of the second polarization analyzer passes through the second polarization analyzer to a second, oscillator, laser rod in the ignitor laser. A second portion of the output of the second polarization analyzer is redirected by the second polarization analyzer to a second optical fiber which delays the beam before the beam is combined with output of the first ignitor laser rod. Output of the second laser rod in the ignitor laser is directed into the first ignitor laser rod which was energized by light passing through the first polarizing analyzer. Combined output of the first ignitor laser rod and output of the second optical fiber is focused into a combustible fuel where the first short duration, high peak power pulse from the ignitor laser ignites the fuel and the second long duration, low peak power pulse directly from the excitation laser sustains the combustion.

  10. Spark gap switch with spiral gas flow

    DOE Patents [OSTI]

    Brucker, John P. (Espanola, NM)

    1989-01-01

    A spark gap switch having a contaminate removal system using an injected gas. An annular plate concentric with an electrode of the switch defines flow paths for the injected gas which form a strong spiral flow of the gas in the housing which is effective to remove contaminates from the switch surfaces. The gas along with the contaminates is exhausted from the housing through one of the ends of the switch.

  11. National Ignition Facility & Photon Science What

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    7 National Ignition Facility & Photon Science What is NiF? the national ignition Facility: bringing star Power to earth The National Ignition Facility (NIF) is the world's largest and highest energy laser system. NIF is an essential experimental tool supporting the stockpile stewardship program of the u.s. department of energy's National Nuclear security Administration. Construction began in 1997, and NIF became operational in march 2009. during experiments, NIF's 192 intense laser beams are

  12. Prediction of spark kernel development in constant volume combustion

    SciTech Connect (OSTI)

    Lim, M.T.; Anderson, R.W.; Arpaci, V.S.

    1987-09-01

    Combustion initiation is studied in atmospheric pressure propane-air mixtures in a constant volume bomb with a high speed (10,000 fps) laser schlieren system. The spark current and voltage waveforms are simultaneously recorded for later model input. A phenomenological model for early flame kernel development is presented which accounts for the initial, breakdown generated, spark kernel and its subsequent growth. The kernel growth is initially controlled by the breakdown process and the subsequent electrical power input. A new, spark power induced, mass entrainment term is shown to model this initially rapid volume increase adequately while later growth is mainly dominated by diffusion. Results and model comparisons are presented for the effects of power input, spark energy, and equivalence ratio.

  13. Laser preheat enhanced ignition

    DOE Patents [OSTI]

    Early, J.W.

    1999-03-02

    A method for enhancing fuel ignition performance by preheating the fuel with laser light at a wavelength that is absorbable by the fuel prior to ignition with a second laser is provided. 11 figs.

  14. Resistance of a water spark.

    SciTech Connect (OSTI)

    Warne, Larry Kevin; Jorgenson, Roy Eberhardt; Lehr, Jane Marie

    2005-11-01

    The later time phase of electrical breakdown in water is investigated for the purpose of improving understanding of the discharge characteristics. One dimensional simulations in addition to a zero dimensional lumped model are used to study the spark discharge. The goal is to provide better electrical models for water switches used in the pulse compression section of pulsed power systems. It is found that temperatures in the discharge channel under representative drive conditions, and assuming small initial radii from earlier phases of development, reach levels that are as much as an order of magnitude larger than those used to model discharges in atmospheric gases. This increased temperature coupled with a more rapidly rising conductivity with temperature than in air result in a decreased resistance characteristic compared to preceding models. A simple modification is proposed for the existing model to enable the approximate calculation of channel temperature and incorporate the resulting conductivity increase into the electrical circuit for the discharge channel. Comparisons are made between the theoretical predictions and recent experiments at Sandia. Although present and past experiments indicated that preceding late time channel models overestimated channel resistance, the calculations in this report seem to underestimate the resistance relative to recent experiments. Some possible reasons for this discrepancy are discussed.

  15. IGNITION AND FRONTIER SCIENCE ON THE NATIONAL IGNITION FACILITY

    SciTech Connect (OSTI)

    Moses, E

    2009-06-22

    The National Ignition Facility (NIF), the world's largest and most powerful laser system for inertial confinement fusion (ICF) and experiments studying high-energy-density (HED) science, is now operational at Lawrence Livermore National Laboratory (LLNL). The NIF construction Project was certified by the Department of Energy as complete on March 30, 2009. NIF, a 192-beam Nd-glass laser facility, will produce 1.8 MJ, 500 TW of light at the third-harmonic, ultraviolet light of 351 nm. On March 10, 2009, a total 192-beam energy of 1.1 MJ was demonstrated; this is approximately 30 times more energy than ever produced in an ICF laser system. The principal goal of NIF is to achieve ignition of a deuterium-tritium (DT) fuel capsule and provide access to HED physics regimes needed for experiments related to national security, fusion energy and for broader frontier scientific exploration. NIF experiments in support of indirect drive ignition will begin in FY2009. These first experiments represent the next phase of the National Ignition Campaign (NIC). The NIC is a 1.7 billion dollar national effort to achieve fusion ignition and is coordinated through a detailed execution plan that includes the science, technology, and equipment. Equipment required for ignition experiments include diagnostics, cryogenic target manipulator, and user optics. Participants in this effort include LLNL, General Atomics (GA), Los Alamos National Laboratory (LANL), Sandia National Laboratory (SNL), and the University of Rochester Laboratory for Energetics (LLE). The primary goal for NIC is to have all of the equipment operational and integrated into the facility and be ready to begin a credible ignition campaign in 2010. With NIF now operational, the long-sought goal of achieving self-sustained nuclear fusion and energy gain in the laboratory is much closer to realization. Successful demonstration of ignition and net energy gain on NIF will be a major step towards demonstrating the feasibility of Inertial Fusion Energy (IFE) and will likely focus the world's attention on the possibility of an ICF energy option. NIF experiments to demonstrate ignition and gain will use central-hot-spot (CHS) ignition, where a spherical fuel capsule is simultaneously compressed and ignited. The scientific basis for CHS has been intensively developed and has high probability of success. Achieving ignition with CHS will open the door for other advanced concepts, such as the use of high-yield pulses of visible wavelength rather than ultraviolet and Fast Ignition concepts. Moreover, NIF will have important scientific applications in such diverse fields as astrophysics, nuclear physics and materials science. The NIC will develop the full set of capabilities required to operate NIF as a major national and international user facility. A solicitation for NIF frontier science experiments to be conducted by the academic community is planned for summer 2009. This paper summarizes the design, performance, and status of NIF, experimental plans for NIC, and will present a brief discussion of the unparalleled opportunities to explore frontier basic science that will be available on the NIF.

  16. Description and performance of the preamplifier for the National Ignition Facility (NIF) laser system

    SciTech Connect (OSTI)

    Crane, J.K.; Martinez, M., Moran, B.

    1996-12-01

    The authors describe the prototype preamplifier for the NIF laser system and discuss the performance of the regenerative amplifier and 4-pass laser systems that comprise the preamplifier.

  17. Tantalum-Tungsten Oxide Thermite Composite Prepared by Sol-Gel Synthesis and Spark Plasma Sintering

    SciTech Connect (OSTI)

    Cervantes, O; Kuntz, J; Gash, A; Munir, Z

    2009-02-13

    Energetic composite powders consisting of sol-gel derived nanostructured tungsten oxide were produced with various amounts of micrometer-scale tantalum fuel metal. Such energetic composite powders were ignition tested and results show that the powders are not sensitive to friction, spark and/or impact ignition. Initial consolidation experiments, using the High Pressure Spark Plasma Sintering (HPSPS) technique, on the sol-gel derived nanostructured tungsten oxide produced samples with higher relative density than can be achieved with commercially available tungsten oxide. The sol-gel derived nanostructured tungsten oxide with immobilized tantalum fuel metal (Ta - WO{sub 3}) energetic composite was consolidated to a density of 9.17 g.cm{sup -3} or 93% relative density. In addition those parts were consolidated without significant pre-reaction of the constituents, thus the sample retained its stored chemical energy.

  18. Are Crab nanoshots Schwinger sparks?

    SciTech Connect (OSTI)

    Stebbins, Albert; Yoo, Hojin

    2015-05-21

    The highest brightness temperature ever observed are from "nanoshots" from the Crab pulsar which we argue could be the signature of bursts of vacuum e pair production. If so this would be the first time the astronomical Schwinger effect has been observed. These "Schwinger sparks" would be an intermittent but extremely powerful, ~103 L?, 10 PeV e accelerator in the heart of the Crab. These nanosecond duration sparks are generated in a volume less than 1 m3 and the existence of such sparks has implications for the small scale structure of the magnetic field of young pulsars such as the Crab. As a result, this mechanism may also play a role in producing other enigmatic bright short radio transients such as fast radio bursts.

  19. Development of a SPARK Training Dataset

    SciTech Connect (OSTI)

    Sayre, Amanda M.; Olson, Jarrod R.

    2015-03-01

    In its first five years, the National Nuclear Security Administrations (NNSA) Next Generation Safeguards Initiative (NGSI) sponsored more than 400 undergraduate, graduate, and post-doctoral students in internships and research positions (Wyse 2012). In the past seven years, the NGSI program has, and continues to produce a large body of scientific, technical, and policy work in targeted core safeguards capabilities and human capital development activities. Not only does the NGSI program carry out activities across multiple disciplines, but also across all U.S. Department of Energy (DOE)/NNSA locations in the United States. However, products are not readily shared among disciplines and across locations, nor are they archived in a comprehensive library. Rather, knowledge of NGSI-produced literature is localized to the researchers, clients, and internal laboratory/facility publication systems such as the Electronic Records and Information Capture Architecture (ERICA) at the Pacific Northwest National Laboratory (PNNL). There is also no incorporated way of analyzing existing NGSI literature to determine whether the larger NGSI program is achieving its core safeguards capabilities and activities. A complete library of NGSI literature could prove beneficial to a cohesive, sustainable, and more economical NGSI program. The Safeguards Platform for Automated Retrieval of Knowledge (SPARK) has been developed to be a knowledge storage, retrieval, and analysis capability to capture safeguards knowledge to exist beyond the lifespan of NGSI. During the development process, it was necessary to build a SPARK training dataset (a corpus of documents) for initial entry into the system and for demonstration purposes. We manipulated these data to gain new information about the breadth of NGSI publications, and they evaluated the science-policy interface at PNNL as a practical demonstration of SPARKs intended analysis capability. The analysis demonstration sought to answer the question, Who leads research and development at PNNL, scientists or policy researchers? The analysis was inconclusive as to whether policy researchers or scientists are primary drivers for research at PNNL. However, the dataset development and analysis activity did demonstrate the utility and usability of the SPARK dataset. After the initiation of the NGSI program there is a clear increase in the number of publications of safeguards products. Employing the natural language analysis tool IN SPIRE showed the presence of vocation- and topic-specific vernacular within NGSI sub-topics. The methodology developed to define the scope of the dataset was useful in describing safeguards applications, but may be applicable for research on other topics beyond safeguards. The analysis emphasized the need for an expanded dataset to fully understand the scope of safeguards publications and research both nationally and internationally. As the SPARK dataset grows to include publications outside PNNL, topics crosscutting disciplines and DOE/NNSA locations should become more apparent. NGSI was established in 2008 to cultivate the next generation of safeguards professionals and support the development of core safeguards capabilities (NNSA 2012). Now a robust system to preserve and share institutional memory such as SPARK is needed to inspire and equip the next generation of safeguards experts, technologies, and policies.

  20. Spark Energy, LP (Massachusetts) | Open Energy Information

    Open Energy Info (EERE)

    Number: 1-877-547-7275 Website: www.sparkenergy.comenhome Twitter: @SparkEnergy Facebook: https:www.facebook.comSparkEnergy Outage Hotline: 1-800-592-2000 References: EIA...

  1. Advanced CFD Models for High Efficiency Compression Ignition Engines |

    Office of Energy Efficiency and Renewable Energy (EERE) Indexed Site

    Department of Energy CFD Models for High Efficiency Compression Ignition Engines Advanced CFD Models for High Efficiency Compression Ignition Engines Advanced CFD models for high efficiency compression-ignition engines can be used to show how turbulence-chemistry interactions influence autoignition and combustion. PDF icon p-19_raja.pdf More Documents & Publications Vehicle Technologies Office Merit Review 2014: High Efficiency GDI Engine Research, with Emphasis on Ignition Systems

  2. Spark gap with low breakdown voltage jitter

    DOE Patents [OSTI]

    Rohwein, G.J.; Roose, L.D.

    1996-04-23

    Novel spark gap devices and electrodes are disclosed. The novel spark gap devices and electrodes are suitable for use in a variety of spark gap device applications. The shape of the electrodes gives rise to local field enhancements and reduces breakdown voltage jitter. Breakdown voltage jitter of approximately 5% has been measured in spark gaps according the invention. Novel electrode geometries and materials are disclosed. 13 figs.

  3. Spark gap with low breakdown voltage jitter

    DOE Patents [OSTI]

    Rohwein, Gerald J. (Albuquerque, NM); Roose, Lars D. (Albuquerque, NM)

    1996-01-01

    Novel spark gap devices and electrodes are disclosed. The novel spark gap devices and electrodes are suitable for use in a variety of spark gap device applications. The shape of the electrodes gives rise to local field enhancements and reduces breakdown voltage jitter. Breakdown voltage jitter of approximately 5% has been measured in spark gaps according the invention. Novel electrode geometries and materials are disclosed.

  4. CHEVROLET | ELECTRIC | GREEN | SPARK EV | TECHNOLOGY. INNOVATION...

    Open Energy Info (EERE)

    CHEVROLET | ELECTRIC | GREEN | SPARK EV | TECHNOLOGY. INNOVATION & SOLUTIONS | GREENER VEHICLES Home There are currently no posts in this category. Syndicate...

  5. Progress Toward Ignition on the National Ignition Facility

    SciTech Connect (OSTI)

    Kauffman, R L

    2011-10-17

    The principal approach to ignition on the National Ignition Facility (NIF) is indirect drive. A schematic of an ignition target is shown in Figure 1. The laser beams are focused through laser entrance holes at each end of a high-Z cylindrical case, or hohlraum. The lasers irradiate the hohlraum walls producing x-rays that ablate and compress the fuel capsule in the center of the hohlraum. The hohlraum is made of Au, U, or other high-Z material. For ignition targets, the hohlraum is {approx}0.5 cm diameter by {approx}1 cm in length. The hohlraum absorbs the incident laser energy producing x-rays for symmetrically imploding the capsule. The fuel capsule is a {approx}2-mm-diameter spherical shell of CH, Be, or C filled with DT fuel. The DT fuel is in the form of a cryogenic layer on the inside of the capsule. X-rays ablate the outside of the capsule, producing a spherical implosion. The imploding shell stagnates in the center, igniting the DT fuel. NIC has overseen installation of all of the hardware for performing ignition experiments, including commissioning of approximately 50 diagnostic systems in NIF. The diagnostics measure scattered optical light, x-rays from the hohlraum over the energy range from 100 eV to 500 keV, and x-rays, neutrons, and charged particles from the implosion. An example of a diagnostic is the Magnetic Recoil Spectrometer (MRS) built by a collaboration of scientists from MIT, UR-LLE, and LLNL shown in Figure 2. MRS measures the neutron spectrum from the implosion, providing information on the neutron yield and areal density that are metrics of the quality of the implosion. Experiments on NIF extend ICF research to unexplored regimes in target physics. NIF can produce more than 50 times the laser energy and more than 20 times the power of any previous ICF facility. Ignition scale hohlraum targets are three to four times larger than targets used at smaller facilities, and the ignition drive pulses are two to five times longer. The larger targets and longer pulse lengths produce unique plasma conditions for laser-plasma instabilities that could reduce hohlraum coupling efficiency. Initial experiments have demonstrated efficient coupling of laser energy to x-rays. X-ray drive greater than 300 eV has been measured in gas-filled ignition hohlraum and shows the expected scaling with laser energy and hohlraum scale size. Experiments are now optimizing capsule implosions for ignition. Ignition conditions require assembling the fuel with sufficient density and temperature for thermonuclear burn. X-rays ablate the outside of the capsule, accelerating and spherically compressing the capsule for assembling the fuel. The implosion stagnates, heating the central core and producing a hot spot that ignites and burns the surrounding fuel. The four main characteristics of the implosion are shell velocity, central hot spot shape, fuel adiabat, and mix. Experiments studying these four characteristics of implosions are used to optimize the implosion. Integrated experiments using cryogenic fuel layer experiments demonstrate the quality of the implosion as the optimization experiments progress. The final compressed fuel conditions are diagnosed by measuring the x-ray emission from the hot core and the neutrons and charged particles produced in the fusion reactions. Metrics of the quality of the implosion are the neutron yield and the shell areal density, as well as the size and shape of the core. The yield depends on the amount of fuel in the hot core and its temperature and is a gauge of the energy coupling to the fuel. The areal density, the density of the fuel times its thickness, diagnoses the fuel assembly, which is measured using the fraction of neutrons that are down scattered passing through the dense shell. The yield and fraction of down scattered neutrons, or shell rho-r, from the cryogenic layered implosions are shown in Figure 3. The different sets of data represent results after a series of implosion optimization experiments. Both yield and areal density show significant increases as a result of the optimization. The experimental Ignition Threshold Factor (ITFX) is a measure of the progress toward ignition. ITFX is analogous to the Lawson Criterion in Magnetic Fusion. Implosions have improved by over a factor of 50 since the first cryogenic layered experiments were done in September 2010. This increase is a measure of the progress made toward the ignition goal in the past year. Optimization experiments are planned in the coming year for continued improvement in implosion performance to achieve the ignition goal. In summary, NIF has made significant progress toward ignition in the 30 months since project completion. Diagnostics and all of the supporting equipment are in place for ignition experiments. The Ignition Campaign is under way as a national collaborative effort of all the National Nuclear Security Administration (NNSA) science laboratories as well as international partners.

  6. Pyrotechnic ignition studies using a gun tunnel

    SciTech Connect (OSTI)

    Evans, N.A.

    1989-01-01

    A gun tunnel is being used to investigate the ignition characteristics of center-hole iron/potassium perchlorate thermal battery discs. Details are given of the construction, operation, and data reduction method for the gun tunnel. To simulate an igniter, this system can readily produce a pulse of hot argon at maximum pressures and temperatures up to P/sub max/ = 8 MPa and T/sub max/ = 4000K, respectively, with flow times of the order of 3 msec. For a single battery disc, a segment of the ignition boundary was found to lie in the region of T/sub max/ = 1200 to 1300K and 0.7 MPa < P/sub max/ < 2.0 MPa. The results also showed two types of ignition: prompt ignition, requiring an average delivered enthalpy /ovr /Delta/H//sub ig/ = 6 cal during an average flow time /ovr /Delta/t//sub ig/ = 0.7 msec, and delayed ignition, with /ovr /Delta/H//sub ig/ = 16 cal and /ovr /Delta/t//sub ig/ = 2.4 msec. In addition, near an ignition boundary, high speed motion photography showed the ignition delay increased to 6 msec with significant spatial non-uniformity. 1 ref., 6 figs.

  7. Stratified-charge glow plug ignition engine experiments. Topical report

    SciTech Connect (OSTI)

    Thring, R.H.; Leet, J.A.

    1991-05-01

    An investigation was conducted to study the feasibility of operating a natural gas two-stroke engine using glow plug ignition with very lean mixtures. The term Stratified-Charge Glow Plus Ignition (SCGI) was coined to describe the engine. A JLO DL 365 single-cylinder, two-stroke, diesel engine was converted first to a natural gas fueled spark-ignited engine for the baseline tests, and then to the SCGI engine. The engine was successfully run, but was found to be sensitive to various conditions such as the glow plug temperature. The engine ran very lean, to an equivalence ratio of 0.33, offering the potential of good fuel economy and low NOx emissions. Numerous photographs, diagrams, and charts are included.

  8. Thermal Issues Associated with the Lighting Systems, Electronics Racks, and Pre-Amplifier Modules in the National Ignition System

    SciTech Connect (OSTI)

    A. C. Owen; J. D. Bernardin; K. L. Lam

    1998-08-01

    This report summarizes an investigation of the thermal issues related to the National Ignition Facility. The influence of heat sources such as lighting fixtures, electronics racks, and pre-amplifier modules (PAMs) on the operational performance of the laser guide beam tubes and optical alignment hardware in the NE laser bays were investigated with experiments and numerical models. In particular, empirical heat transfer data was used to establish representative and meaningful boundary conditions and also serve as bench marks for computational fluid dynamics (CFD) models. Numerical models, constructed with a commercial CFD code, were developed to investigate the extent of thermal plumes and radiation heat transfer from the heat sources. From these studies, several design modifications were recommended including reducing the size of all fluorescent lights in the NIF laser bays to single 32 W bulb fixtures, maintaining minimum separation distances between light fixtures/electronics racks and beam transport hardware, adding motion sensors in areas of the laser bay to control light fixture operation during maintenance procedures, properly cooling all electronics racks with air-water heat exchangers with heat losses greater than 25 W/rack to the M1 laser bay, ensuring that the electronics racks are not overcooked and thus maintain their surface temperatures to within a few degrees centigrade of the mean air temperature, and insulating the electronic bays and optical support structures on the PAMs.

  9. COLLOQUIUM: In Pursuit of Ignition on the National Ignition Facility...

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Fusion (ICF) Program is conducting experiments at the National Ignition Facility (NIF) at the Lawrence Livermore National Laboratory with the goal of igniting a propagating...

  10. Analysis of Homogeneous Charge Compression Ignition (HCCI) Engines for Cogeneration Applications

    SciTech Connect (OSTI)

    Aceves, S; Martinez-Frias, J; Reistad, G

    2004-04-30

    This paper presents an evaluation of the applicability of Homogeneous Charge Compression Ignition Engines (HCCI) for small-scale cogeneration (less than 1 MWe) in comparison to five previously analyzed prime movers. The five comparator prime movers include stoichiometric spark-ignited (SI) engines, lean burn SI engines, diesel engines, microturbines and fuel cells. The investigated option, HCCI engines, is a relatively new type of engine that has some fundamental differences with respect to other prime movers. Here, the prime movers are compared by calculating electric and heating efficiency, fuel consumption, nitrogen oxide (NOx) emissions and capital and fuel cost. Two cases are analyzed. In Case 1, the cogeneration facility requires combined power and heating. In Case 2, the requirement is for power and chilling. The results show that the HCCI engines closely approach the very high fuel utilization efficiency of diesel engines without the high emissions of NOx and the expensive diesel fuel. HCCI engines offer a new alternative for cogeneration that provides a unique combination of low cost, high efficiency, low emissions and flexibility in operating temperatures that can be optimally tuned for cogeneration systems. HCCI engines are the most efficient technology that meets the oncoming 2007 CARB NOx standards for cogeneration engines. The HCCI engine appears to be a good option for cogeneration systems and merits more detailed analysis and experimental demonstration.

  11. Low profile thermite igniter

    SciTech Connect (OSTI)

    Halcomb, Danny L.; Mohler, Jonathan H.

    1991-03-05

    A thermite igniter/heat source comprising a housing, high-density thermite, and low-density thermite. The housing has a relatively low profile and can focus energy by means of a torch-like ejection of hot reaction products and is externally ignitable.

  12. Advanced CFD Models for High Efficiency Compression Ignition...

    Office of Energy Efficiency and Renewable Energy (EERE) Indexed Site

    Vehicle Technologies Office Merit Review 2014: High Efficiency GDI Engine Research, with Emphasis on Ignition Systems Advanced Combustion Modeling with STAR-CD using Transient ...

  13. Spark Energy, LP (Connecticut) | Open Energy Information

    Open Energy Info (EERE)

    Connecticut) Jump to: navigation, search Name: Spark Energy, LP Place: Connecticut Phone Number: 1-877-547-7275 Website: www.sparkenergy.comenconnect Outage Hotline:...

  14. Education Highlights: Gasoline Compression Ignition | Argonne National

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Laboratory Education Highlights: Gasoline Compression Ignition Share Description Argonne intern Kendyl Partridge from Mississippi State University worked with Argonne mentor Steve Ciatti of the Energy Systems division in studying gasoline compression ignition engines. This research will help engineers increase an engine's efficiency while reducing its environmental impact. Speakers Kendyl Partridge, Argonne National Laboratory Intern from Mississippi State University Duration 1:56 Topic

  15. Gas mixtures for spark gap closing switches

    DOE Patents [OSTI]

    Christophorou, Loucas G. (Oak Ridge, TN); McCorkle, Dennis L. (Knoxville, TN); Hunter, Scott R. (Oak Ridge, TN)

    1988-01-01

    Gas mixtures for use in spark gap closing switches comprised of fluorocarbons and low molecular weight, inert buffer gases. To this can be added a third gas having a low ionization potential relative to the buffer gas. The gas mixtures presented possess properties that optimized the efficiency spark gap closing switches.

  16. Gas mixtures for spark gap closing switches

    DOE Patents [OSTI]

    Christophorou, L.G.; McCorkle, D.L.; Hunter, S.R.

    1987-02-20

    Gas mixtures for use in spark gap closing switches comprised of fluorocarbons and low molecular weight, inert buffer gases. To this can be added a third gas having a low ionization potential relative to the buffer gas. The gas mixtures presented possess properties that optimized the efficiency spark gap closing switches. 6 figs.

  17. Combustion, Efficiency, and Fuel Effects in a Spark-Assisted...

    Office of Energy Efficiency and Renewable Energy (EERE) Indexed Site

    Combustion, Efficiency, and Fuel Effects in a Spark-Assisted HCCI Gasoline Engine Combustion, Efficiency, and Fuel Effects in a Spark-Assisted HCCI Gasoline Engine 2004 Diesel...

  18. Spark Green Energy Pvt Ltd | Open Energy Information

    Open Energy Info (EERE)

    Spark Green Energy Pvt Ltd Jump to: navigation, search Name: Spark Green Energy Pvt Ltd. Place: Mumbai, Maharashtra, India Zip: 400 050 Sector: Biomass Product: Mumbai-based...

  19. Blue Spark Technologies formerly Thin Battery Technologies Inc...

    Open Energy Info (EERE)

    Spark Technologies formerly Thin Battery Technologies Inc Jump to: navigation, search Name: Blue Spark Technologies (formerly Thin Battery Technologies Inc.) Place: Westlake, Ohio...

  20. Load Expansion of Stoichiometric HCCI Using Spark Assist and...

    Office of Energy Efficiency and Renewable Energy (EERE) Indexed Site

    of Stoichiometric HCCI Using Spark Assist and Hydraulic Valve Actuation Load Expansion of Stoichiometric HCCI Using Spark Assist and Hydraulic Valve Actuation Presentation given at...

  1. National Ignition Facility & Photon Science What

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Ignition Facility & Photon Science What is NiF? the national ignition Facility: bringing star Power to earth The National Ignition Facility (NIF) is the world's largest and...

  2. Semiconductor bridge, SCB, ignition of energetic materials

    SciTech Connect (OSTI)

    Bickes, R.W.; Grubelich, M.D.; Harris, S.M.; Merson, J.A.; Tarbell, W.W.

    1997-04-01

    Sandia National Laboratories` semiconductor bridge, SCB, is now being used for the ignition or initiation of a wide variety of exeoergic materials. Applications of this new technology arose because of a need at the system level to provide light weight, small volume and low energy explosive assemblies. Conventional bridgewire devices could not meet the stringent size, weight and energy requirements of our customers. We present an overview of SCB technology and the ignition characteristics for a number of energetic materials including primary and secondary explosives, pyrotechnics, thermites and intermetallics. We provide examples of systems designed to meet the modern requirements that sophisticated systems must satisfy in today`s market environments.

  3. Using indium tin oxide material to implement the imaging of microwave plasma ignition process

    SciTech Connect (OSTI)

    Wang, Qiang; Hou, Lingyun; Zhang, Guixin Zhang, Boya; Liu, Cheng; Wang, Zhi; Huang, Jian

    2014-02-17

    In this paper, a method is introduced to get global observation of microwave plasma ignition process at high pressure. A microwave resonator was designed with an indium tin oxide coated glass at bottom. Microwave plasma ignition was implemented in methane and air mixture at 10 bars by a 2?ms-3?kW-2.45?GHz microwave pulse, and the high speed images of the ignition process were obtained. The images visually proved that microwave plasma ignition could lead to a multi-point ignition. The system may also be applied to obtain Schlieren images, which is commonly used to observe the development of flame kernel in an ignition process.

  4. National Ignition Facility | National Nuclear Security Administration

    National Nuclear Security Administration (NNSA)

    and Evaluation Inertial Confinement Fusion ICF Facilities National Ignition ... leading to demonstrate fusion ignition and thermonuclear burn in the laboratory. ...

  5. Heating National Ignition Facility, Realistic Financial Planning...

    Office of Environmental Management (EM)

    National Ignition Facility, Realistic Financial Planning & Rapid Modification Lessons Learned Report Apr 2010 Heating National Ignition Facility, Realistic Financial Planning &...

  6. Experimental Component Characterization, Monte-Carlo-Based Image Generation and Source Reconstruction for the Neutron Imaging System of the National Ignition Facility

    SciTech Connect (OSTI)

    Barrera, C A; Moran, M J

    2007-08-21

    The Neutron Imaging System (NIS) is one of seven ignition target diagnostics under development for the National Ignition Facility. The NIS is required to record hot-spot (13-15 MeV) and downscattered (6-10 MeV) images with a resolution of 10 microns and a signal-to-noise ratio (SNR) of 10 at the 20% contour. The NIS is a valuable diagnostic since the downscattered neutrons reveal the spatial distribution of the cold fuel during an ignition attempt, providing important information in the case of a failed implosion. The present study explores the parameter space of several line-of-sight (LOS) configurations that could serve as the basis for the final design. Six commercially available organic scintillators were experimentally characterized for their light emission decay profile and neutron sensitivity. The samples showed a long lived decay component that makes direct recording of a downscattered image impossible. The two best candidates for the NIS detector material are: EJ232 (BC422) plastic fibers or capillaries filled with EJ399B. A Monte Carlo-based end-to-end model of the NIS was developed to study the imaging capabilities of several LOS configurations and verify that the recovered sources meet the design requirements. The model includes accurate neutron source distributions, aperture geometries (square pinhole, triangular wedge, mini-penumbral, annular and penumbral), their point spread functions, and a pixelated scintillator detector. The modeling results show that a useful downscattered image can be obtained by recording the primary peak and the downscattered images, and then subtracting a decayed version of the former from the latter. The difference images need to be deconvolved in order to obtain accurate source distributions. The images are processed using a frequency-space modified-regularization algorithm and low-pass filtering. The resolution and SNR of these sources are quantified by using two surrogate sources. The simulations show that all LOS configurations have a resolution of 7 microns or better. The 28 m LOS with a 7 x 7 array of 100-micron mini-penumbral apertures or 50-micron square pinholes meets the design requirements and is a very good design alternative.

  7. Scientists ignite aluminum water mix

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Scientists ignite aluminum water mix Scientists ignite aluminum water mix Don't worry, that beer can you're holding is not going to spontaneously burst into flames. June 30, 2014 Los Alamos National Laboratory chemist Bryce Tappan ignites a small quantity of aluminum nanoparticle water mixture. In open air, the compound burns like a Fourth of July sparkler. Los Alamos National Laboratory chemist Bryce Tappan ignites a small quantity of aluminum nanoparticle water mixture. In open air, the

  8. XEMC Spark Gansu JV | Open Energy Information

    Open Energy Info (EERE)

    Gansu Province, China Sector: Wind energy Product: China-based JV for wind turbine manufacture. References: XEMC & Spark & Gansu JV1 This article is a stub. You can help OpenEI...

  9. Sparks, Texas: Energy Resources | Open Energy Information

    Open Energy Info (EERE)

    is a stub. You can help OpenEI by expanding it. Sparks is a census-designated place in El Paso County, Texas.1 References US Census Bureau 2005 Place to 2006 CBSA Retrieved...

  10. National Ignition Facility | Princeton Plasma Physics Lab

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    National Ignition Facility Subscribe to RSS - National Ignition Facility National Ignition Facility Image: National Ignition Facility Summary of Assessment of Prospects for Inertial Fusion Energy Read more about Summary of Assessment of Prospects for Inertial Fusion Energy National Ignition Facility (NIF): Under Pressure: Ramp-Compression Smashes Record Read more about National Ignition Facility (NIF): Under Pressure: Ramp-Compression Smashes Record NATIONAL IGNITION FACILITY Read more about

  11. homogeneous charge compression ignition

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    homogeneous charge compression ignition - Sandia Energy Energy Search Icon Sandia Home Locations Contact Us Employee Locator Energy & Climate Secure & Sustainable Energy Future Stationary Power Energy Conversion Efficiency Solar Energy Wind Energy Water Power Supercritical CO2 Geothermal Natural Gas Safety, Security & Resilience of the Energy Infrastructure Energy Storage Nuclear Power & Engineering Grid Modernization Battery Testing Nuclear Fuel Cycle Defense Waste Management

  12. Ignition dynamics of high explosives

    SciTech Connect (OSTI)

    Ali, A.N.; Son, S.F.; Sander, R.K.; Asay, B.W.; Brewster, M.Q.

    1999-04-01

    The laser ignition of the explosives HMX (octahydro-1,3,5,7-tetranitro-1,3,5,7-tetrazocine, C{sub 4}H{sub 8}N{sub 8}O{sub 8}), {delta}-phase HMX, PBX 9501 (95% HMX, 2.5% Estane, 2.5% BDNPA/BDNPF), TATB (1,3,5-triamino-2,4,6-trinitrobenzene, C{sub 6}H{sub 6}N{sub 6}O{sub 6}), and PBX 9502 (95% TATB, 5% Kel-F) and aged PBX 9502 has been conducted with the intent to compare the relative sensitivities of those explosives and to investigate the effect of beam profile, binder addition, and porosity. It has been found that there was little difference between a gaussian beam and a top hat profile on the laser ignition of HMX. The authors observe that the addition of binder in the amounts present in PBX 9501 resulted in longer ignition delays than that of HMX. In contrast to HMX, the addition of binder to TATB in PBX 9502 shows no measurable effect. Porosity effects were considered by comparing the ignition of granular HMX and pressed HMX pellets. Porosity appears to increase ignition delay due to an increased effective absorption scale and increased convective heat loss. This porosity effect also resulted in longer ignition delays for {delta}-phase HMX than for {beta}-phase HMX. In order to simulate ignition in voids or cracks, the standard ignition experiment was modified to include a NaCl window placed at variable distances above the sample surface. When ignition experiments were performed at 29 W/cm{sup 2} and 38 W/cm{sup 2} a critical gap distance was observed of 6 {+-} 0.4 mm below which ignition was severely inhibited. This result underscores the importance of gas phase processes in ignition and illustrates that conditions can exist where simple ignition criteria such as surface temperature is inadequate.

  13. Lightweight Technology Resolved Challenge Facing the Chevy Spark...

    Office of Energy Efficiency and Renewable Energy (EERE) Indexed Site

    August 18, 2015 - 11:34am Addthis The Chevy Spark EV at the Washington Auto Show. The Chevy Spark EV at the Washington Auto Show. Technology innovation comes in many forms - ...

  14. Spark Energy, LP (New York) | Open Energy Information

    Open Energy Info (EERE)

    Place: New York Phone Number: 1-877-547-7275 Website: www.sparkenergy.comennew-yor Twitter: @SparkEnergy Facebook: https:www.facebook.comSparkEnergy Outage Hotline:...

  15. X-ray Streak Camera Cathode Development and Timing Accuracy of the 4w UV Fiducial System at the National Ignition Facility

    SciTech Connect (OSTI)

    Opachich, Y P; Palmer, N; Homoelle, D; Hatch, B W; Bell, P; Bradley, D; Kalantar, D; Browning, D; Landen, O

    2012-05-02

    The convergent ablator experiments at the National Ignition Facility (NIF) are designed to measure the peak velocity and remaining ablator mass of an indirectly driven imploding capsule. Such a measurement can be performed using an x-ray source to backlight the capsule and an x-ray streak camera to record the capsule as it implodes. The ultimate goal of this experiment is to achieve an accuracy of 2% in the velocity measurement, which translates to a {+-}2 ps temporal accuracy over any 300 ps interval for the streak camera. In order to achieve this, a 4-{omega} (263nm) temporal fiducial system has been implemented for the x-ray streak camera at NIF. Aluminum, Titanium, Gold and Silver photocathode materials have been tested. Aluminum showed the highest quantum efficiency, with five times more peak signal counts per fiducial pulse when compared to Gold. The fiducial pulse data was analyzed to determine the centroiding a statistical accuracy for incident laser pulse energies of 1 and 10 nJ, showing an accuracy of {+-}1.6 ps and {+-}0.7 ps respectively.

  16. National Ignition Facility & Photon Science

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    security maintaining the nuclear weapons stockpile As the largest, highest-energy laser ever built, the National Ignition Facility (NIF) can create conditions in the ...

  17. Lightweight Technology Resolved Challenge Facing the Chevy Spark EV Battery

    Office of Energy Efficiency and Renewable Energy (EERE) Indexed Site

    Tray and Enclosure | Department of Energy Lightweight Technology Resolved Challenge Facing the Chevy Spark EV Battery Tray and Enclosure Lightweight Technology Resolved Challenge Facing the Chevy Spark EV Battery Tray and Enclosure August 18, 2015 - 11:34am Addthis The Chevy Spark EV at the Washington Auto Show. The Chevy Spark EV at the Washington Auto Show. Technology innovation comes in many forms - sometimes, it's as simple as adapting a recent but un-commercialized innovation to a

  18. Alternative Fuels Data Center: Partnerships Spark Biodiesel Success for

    Alternative Fuels and Advanced Vehicles Data Center [Office of Energy Efficiency and Renewable Energy (EERE)]

    Essential Baking Company Partnerships Spark Biodiesel Success for Essential Baking Company to someone by E-mail Share Alternative Fuels Data Center: Partnerships Spark Biodiesel Success for Essential Baking Company on Facebook Tweet about Alternative Fuels Data Center: Partnerships Spark Biodiesel Success for Essential Baking Company on Twitter Bookmark Alternative Fuels Data Center: Partnerships Spark Biodiesel Success for Essential Baking Company on Google Bookmark Alternative Fuels Data

  19. Fusion and Ignition

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    science Fusion and Ignition What is Fusion? Fusion is the process that powers the sun and the stars. Fusion describes what happens when the nuclei of light atoms overcome the electrical resistance that keeps them apart and get close enough to activate the strong nuclear force that holds them together, or "fuse." When fused, they form a bigger nucleus; two elements combine to create a different element at the level of the nucleus. Making elements fuse requires an enormous amount of heat

  20. Spark gap device for precise switching

    DOE Patents [OSTI]

    Boettcher, G.E.

    1984-10-02

    A spark gap device for precise switching of an energy storage capacitor into an exploding bridge wire load is disclosed. Niobium electrodes having a melting point of 2,415 degrees centigrade are spaced apart by an insulating cylinder to define a spark gap. The electrodes are supported by conductive end caps which, together with the insulating cylinder, form a hermetically sealed chamber filled with an inert, ionizable gas, such as pure xenon. A quantity of solid radioactive carbon-14 within the chamber adjacent the spark gap serves as a radiation stabilizer. The sides of the electrodes and the inner wall of the insulating cylinder are spaced apart a sufficient distance to prevent unwanted breakdown initiation. A conductive sleeve may envelop the outside of the insulating member from the midpoint of the spark gap to the cap adjacent the cathode. The outer metallic surfaces of the device may be coated with a hydrogen-impermeable coating to lengthen the shelf life and operating life of the device. The device breaks down at about 1,700 volts for input voltage rates up to 570 volts/millisecond and allows peak discharge currents of up to 3,000 amperes from a 0.3 microfarad energy storage capacitor for more than 1,000 operations. 3 figs.

  1. Spark gap device for precise switching

    DOE Patents [OSTI]

    Boettcher, Gordon E. (Albuquerque, NM)

    1984-01-01

    A spark gap device for precise switching of an energy storage capacitor into an exploding bridge wire load is disclosed. Niobium electrodes having a melting point of 2,415 degrees centrigrade are spaced apart by an insulating cylinder to define a spark gap. The electrodes are supported by conductive end caps which, together with the insulating cylinder, form a hermetically sealed chamber filled with an inert, ionizable gas, such as pure xenon. A quantity of solid radioactive carbon-14 within the chamber adjacent the spark gap serves as a radiation stabilizer. The sides of the electrodes and the inner wall of the insulating cylinder are spaced apart a sufficient distance to prevent unwanted breakdown initiation. A conductive sleeve may envelop the outside of the insulating member from the midpoint of the spark gap to the cap adjacent the cathode. The outer metallic surfaces of the device may be coated with a hydrogen-impermeable coating to lengthen the shelf life and operating life of the device. The device breaks down at about 1,700 volts for input voltage rates up to 570 volts/millisecond and allows peak discharge currents of up to 3,000 amperes from a 0.3 microfarad energy storage capacitor for more than 1,000 operations.

  2. Ignite High Tech Startups | Open Energy Information

    Open Energy Info (EERE)

    Name: Ignite High Tech Startups Place: United States Sector: Services Product: General Financial & Legal Services ( Private family-controlled ) References: Ignite High Tech...

  3. An Analysis of Direct-injection spark-ignition (DISI) soot morphology

    SciTech Connect (OSTI)

    Barone, Teresa L; Storey, John Morse; Youngquist, Adam D; Szybist, James P

    2012-01-01

    We have characterized particle emissions produced by a 4-cylinder, 2.0 L DISI engine using transmission electron microscopy (TEM) and image analysis. Analyses of soot morphology provide insight to particle formation mechanisms and strategies for prevention. Particle emissions generated by two fueling strategies were investigated, early injection and injection modified for low particle number concentration emissions. A blend of 20% ethanol and 80% emissions certification gasoline was used for the study given the likelihood of increased ethanol content in widely available fuel. In total, about 200 particles and 3000 primary soot spherules were individually measured. For the fuel injection strategy which produced low particle number concentration emissions, we found a prevalence of single solid sub-25 nm particles and fractal-like aggregates. The modal diameter of single solid particles and aggregate primary particles was between 10 and 15 nm. Solid particles as small as 6 nm were present. Although nanoparticle aggregates had fractal-like morphology similar to diesel soot, the average primary particle diameter per aggregate had a much wider range that spanned from 7 to 60 nm. For the early fuel injection strategy, liquid droplets were prevalent, and the modal average primary particle diameter was between 20 and 25 nm. The presence of liquid droplets may have been the result of unburned fuel and/or lubricating oil originating from fuel impingement on the piston or cylinder wall; the larger modal aggregate primary particle diameter suggests greater fuel-rich zones in-cylinder than for the low particle number concentration point. However, both conditions produced aggregates with a wide range of primary particle diameters, which indicates heterogeneous fuel and air mixing.

  4. Advanced Lean-Burn DI Spark Ignition Fuels Research | Department of Energy

    Office of Energy Efficiency and Renewable Energy (EERE) Indexed Site

    09 DOE Hydrogen Program and Vehicle Technologies Program Annual Merit Review and Peer Evaluation Meeting, May 18-22, 2009 -- Washington D.C. PDF icon ft_06_sjoberg.pdf More Documents & Publications HCCI and Stratified-Charge CI Engine Combustion

  5. Vehicle Technologies Office Merit Review 2015: Advanced Lean-Burn DI Spark Ignition Fuels Research

    Broader source: Energy.gov [DOE]

    Presentation given by Sandia National Laboratory at 2015 DOE Hydrogen and Fuel Cells Program and vehicle technologies office annual merit review and peer evaluation meeting about advanced lean-burn...

  6. Vehicle Technologies Office Merit Review 2014: Advanced Lean-Burn DI Spark Ignition Fuels Research

    Broader source: Energy.gov [DOE]

    Presentation given by Sandia National Laboratories at 2014 DOE Hydrogen and Fuel Cells Program and Vehicle Technologies Office Annual Merit Review and Peer Evaluation Meeting about advanced lean...

  7. Advantages of Oxygenates Fuels over Gasoline in Direct Injection Spark Ignition Engines

    Broader source: Energy.gov [DOE]

    Poster presented at the 16th Directions in Engine-Efficiency and Emissions Research (DEER) Conference in Detroit, MI, September 27-30, 2010.

  8. Ignition and burn of a small magnetized fuel target

    SciTech Connect (OSTI)

    Kirkpatrick, Ronald C.

    2012-06-01

    The crucial step for inertial confinement fusion (ICF) is ignition, which leads to sufficiently high gain to enable design of a power producing system. Thus far, this step has not been demonstrated. Magnetized targets may provide an alternative path to ignition. In addition, the 1-D calculations presented here suggest that this approach may provide the gain and other characteristics needed for a practical fusion reactor.

  9. Ignition of Aluminum Particles and Clouds

    SciTech Connect (OSTI)

    Kuhl, A L; Boiko, V M

    2010-04-07

    Here we review experimental data and models of the ignition of aluminum (Al) particles and clouds in explosion fields. The review considers: (i) ignition temperatures measured for single Al particles in torch experiments; (ii) thermal explosion models of the ignition of single Al particles; and (iii) the unsteady ignition Al particles clouds in reflected shock environments. These are used to develop an empirical ignition model appropriate for numerical simulations of Al particle combustion in shock dispersed fuel explosions.

  10. NEVADA SPARKS RESIDENTS TO IMPROVE ENERGY FITNESS | Department of Energy

    Energy Savers [EERE]

    NEVADA SPARKS RESIDENTS TO IMPROVE ENERGY FITNESS NEVADA SPARKS RESIDENTS TO IMPROVE ENERGY FITNESS NEVADA SPARKS RESIDENTS TO IMPROVE ENERGY FITNESS Following significant population growth and economic prosperity in the last decade, Nevada was hit by the economic downturn with some of the highest rates of foreclosure and unemployment in the country from 2011 to 2014. The state's unemployment rate was particularly high for home improvement professionals. To combat these challenges, EnergyFit

  11. 5 Energy Education Ideas to Spark Learning Beyond the Classroom |

    Office of Energy Efficiency and Renewable Energy (EERE) Indexed Site

    Department of Energy Energy Education Ideas to Spark Learning Beyond the Classroom 5 Energy Education Ideas to Spark Learning Beyond the Classroom August 4, 2015 - 12:01pm Addthis 5 Energy Education Ideas to Spark Learning Beyond the Classroom Joshua Sneideman Joshua Sneideman Albert Einstein Distinguished Educator Fellow Did you know energy is everywhere? Think about it: energy is clearly a physics concept, but is that all it is? Like turning off the lights when you leave home, our everyday

  12. National Ignition Facility (NIF): Under Pressure: Ramp-Compression...

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    National Ignition Facility (NIF): Under Pressure: Ramp-Compression Smashes Record American Fusion News Category: National Ignition Facility Link: National Ignition Facility (NIF):...

  13. Calling All Majors: Sparking Clean Energy Interest from Students...

    Office of Energy Efficiency and Renewable Energy (EERE) Indexed Site

    Calling All Majors: Sparking Clean Energy Interest from Students in Washington Calling All ... spring 2013 "Applications in Energy Production" course get an up-close view of how ...

  14. Spark Solar Australia Proprietary Limited | Open Energy Information

    Open Energy Info (EERE)

    Jump to: navigation, search Name: Spark Solar Australia Proprietary Limited Place: O Connor, Australian Capital Territory, Australia Zip: 2602 Product: Australia-based...

  15. Evaluation of unthrottled combustion system options for light duty applications with future syncrude derived fuels. Alternative Fuels Utilization Program

    SciTech Connect (OSTI)

    Needham, J. R.; Cooper, B. M.; Norris-Jones, S. R.

    1982-12-01

    An experimental program examining the interaction between several fuel and light duty automotive engine combinations is detailed. Combustion systems addressed covered indirect and direct injection diesel and spark ignited stratified charge. Fuels primarily covered D2, naphtha and intermediate broadcut blends. Low ignition quality diesel fuels were also evaluated. The results indicate the baseline fuel tolerance of each combustion system and enable characteristics of the systems to be compared. Performance, gaseous and particulate emissions aspects were assessed. The data obtained assists in the selection of candidate combustion systems for potential future fuels. Performance and environmental penalties as appropriate are highlighted relative to the individual candidates. Areas of further work for increased understanding are also reviewed.

  16. SCB thermite igniter studies

    SciTech Connect (OSTI)

    Bickes, R.W. Jr.; Wackerbarth, D.E.; Mohler, J.H.

    1996-12-31

    The authors report on recent studies comparing the ignition threshold of temperature cycled, SCB thermite devices with units that were not submitted to temperature cycling. Aluminum/copper-oxide thermite was pressed into units at two densities, 45% of theoretical maximum density (TMD) or 47% of TMD. Half of each of the density sets underwent three thermal cycles; each cycle consisted of 2 hours at 74 C and 2 hours at {minus}54 C, with a 5 minute maximum transfer time between temperatures. The temperature cycled units were brought to ambient temperature before the threshold testing. Both the density and the thermal cycling affected the all-fire voltage. Using a 5.34 {micro}F CDU (capacitor discharge unit) firing set, the all-fire voltage for the units that were not temperature cycled increased with density from 32.99 V (45% TMD) to 39.32 V (47% TMD). The all-fire voltages for the thermally cycled units were 34.42 V (45% TMD) and 58.1 V (47% TMD). They also report on no-fire levels at ambient temperature for two component designs; the 5 minute no-fire levels were greater than 1.2 A. Units were also subjected to tests in which 1 W of RF power was injected into the bridges at 10 MHz for 5 minutes. The units survived and fired normally afterwards. Finally, units were subjected to pin-to-pin electrostatic discharge (ESD) tests. None of the units fired upon application of the ESD pulse, and all of the tested units fired normally afterwards.

  17. Pilot fuel ignited stratified charge rotary combustion engine and fuel injector therefor

    SciTech Connect (OSTI)

    Loyd, R. W.

    1980-02-12

    For a pilot fuel ignited stratified charge rotary, internal combustion engine, the fuel injection system and a fuel injector therefor comprises a fuel injector having plural discharge ports with at least one of the discharge ports located to emit a ''pilot'' fuel charge (relatively rich fuel-air mixture) into a passage in the engine housing, which passage communicates with the engine combustion chambers. An ignition element is located in the passage to ignite the ''pilot'' fuel (a relatively rich fuel-air mixture) flowing through the passage. At least one other discharge port of the fuel injector is in substantially direct communication with the combustion chambers of the engine to emit a main fuel charge into the latter. The ignited ''pilot'' fuelair mixture, when ignited, flashes into the combustion chambers to ignite the main, relatively lean, fuel-air mixture which is in the combustion chambers.

  18. June 11, 1999: National Ignition Facility | Department of Energy

    Energy Savers [EERE]

    1, 1999: National Ignition Facility June 11, 1999: National Ignition Facility June 11, 1999: National Ignition Facility June 11, 1999 Secretary Richardson dedicates the National Ignition Facility target chamber at DOE's Lawrence Livermore National Laboratory.

  19. Observing the Sparks of Life | Photosynthetic Antenna Research Center

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Observing the Sparks of Life December 31, 2013 Observing the Sparks of Life EFRC researchers isolate a photosynthetic complex - arguably the most important bit of organic chemistry on the planet - in its complete functioning state. http://science.energy.gov/discovery-and-innovation/stories/2013/127045/ In the News

  20. Laser ablation based fuel ignition

    DOE Patents [OSTI]

    Early, James W. (Los Alamos, NM); Lester, Charles S. (San Juan Pueblo, NM)

    1998-01-01

    There is provided a method of fuel/oxidizer ignition comprising: (a) application of laser light to a material surface which is absorptive to the laser radiation; (b) heating of the material surface with the laser light to produce a high temperature ablation plume which emanates from the heated surface as an intensely hot cloud of vaporized surface material; and (c) contacting the fuel/oxidizer mixture with the hot ablation cloud at or near the surface of the material in order to heat the fuel to a temperature sufficient to initiate fuel ignition.

  1. Laser ablation based fuel ignition

    DOE Patents [OSTI]

    Early, J.W.; Lester, C.S.

    1998-06-23

    There is provided a method of fuel/oxidizer ignition comprising: (a) application of laser light to a material surface which is absorptive to the laser radiation; (b) heating of the material surface with the laser light to produce a high temperature ablation plume which emanates from the heated surface as an intensely hot cloud of vaporized surface material; and (c) contacting the fuel/oxidizer mixture with the hot ablation cloud at or near the surface of the material in order to heat the fuel to a temperature sufficient to initiate fuel ignition. 3 figs.

  2. The National Ignition Facility and the Path to Fusion Energy

    SciTech Connect (OSTI)

    Moses, E

    2011-07-26

    The National Ignition Facility (NIF) is operational and conducting experiments at the Lawrence Livermore National Laboratory (LLNL). The NIF is the world's largest and most energetic laser experimental facility with 192 beams capable of delivering 1.8 megajoules of 500-terawatt ultraviolet laser energy, over 60 times more energy than any previous laser system. The NIF can create temperatures of more than 100 million degrees and pressures more than 100 billion times Earth's atmospheric pressure. These conditions, similar to those at the center of the sun, have never been created in the laboratory and will allow scientists to probe the physics of planetary interiors, supernovae, black holes, and other phenomena. The NIF's laser beams are designed to compress fusion targets to the conditions required for thermonuclear burn, liberating more energy than is required to initiate the fusion reactions. Experiments on the NIF are focusing on demonstrating fusion ignition and burn via inertial confinement fusion (ICF). The ignition program is conducted via the National Ignition Campaign (NIC) - a partnership among LLNL, Los Alamos National Laboratory, Sandia National Laboratories, University of Rochester Laboratory for Laser Energetics, and General Atomics. The NIC program has also established collaborations with the Atomic Weapons Establishment in the United Kingdom, Commissariat a Energie Atomique in France, Massachusetts Institute of Technology, Lawrence Berkeley National Laboratory, and many others. Ignition experiments have begun that form the basis of the overall NIF strategy for achieving ignition. Accomplishing this goal will demonstrate the feasibility of fusion as a source of limitless, clean energy for the future. This paper discusses the current status of the NIC, the experimental steps needed toward achieving ignition and the steps required to demonstrate and enable the delivery of fusion energy as a viable carbon-free energy source.

  3. Type B Accident Investigation, Subcontractor Employee Personal Protective Equipment Ignition Incident on February 18, 2003, at the East Tennessee Technology Park, Oak Ridge, Tennessee

    Broader source: Energy.gov [DOE]

    On February 18, 2003, a general laborer employed at the East Tennessee Technology Park (ETTP) by MACTEC Constructors, Inc. (MACTEC) was performing rebar removal with a gas-powered cut-off machine. MACTEC is a subcontractor to Bechtel Jacobs Company LL (BJC). The sparks from the cut-off machine ignited the right leg of his 100% cotton anticontamination (anti-c) coveralls and the plastic bootie.

  4. Integral low-energy thermite igniter

    DOE Patents [OSTI]

    Gibson, A.; Haws, L.D.; Mohler, J.H.

    1983-05-13

    In a thermite igniter/heat source comprising a container holding an internal igniter load, there is provided the improvement wherein the container consists essentially of consumable consolidated thermite having a low gas output upon combustion, whereby upon ignition, substantially all of the container and said load is consumed with low gas production.

  5. Integral low-energy thermite igniter

    SciTech Connect (OSTI)

    Gibson, Albert; Haws, Lowell D.; Mohler, Jonathan H.

    1984-08-14

    In a thermite igniter/heat source comprising a container holding an internal igniter load, there is provided the improvement wherein the container consists essentially of consumable consolidated thermite having a low gas output upon combustion, whereby upon ignition, substantially all of the container and said load is consumed with low gas production.

  6. Desensitizing nano powders to electrostatic discharge ignition

    SciTech Connect (OSTI)

    Steelman, Ryan; Clark, Billy; Pantoya, Michelle L.; Heaps, Ronald J.; Daniels, Michael A.

    2015-08-01

    Electrostatic discharge (ESD) is a main cause for ignition in powder media ranging from grain silos to fireworks. Nanoscale particles are orders of magnitude more ESD ignition sensitive than their micron scale counterparts. This study shows that at least 13 vol. % carbon nanotubes (CNT) added to nano-aluminum and nano-copper oxide particles (nAl + CuO) eliminates ESD ignition sensitivity. The CNT act as a conduit for electric energy and directs electric charge through the powder to desensitize the reactive mixture to ignition. For nanoparticles, the required CNT concentration for desensitizing ESD ignition acts as a diluent to quench energy propagation.

  7. High-voltage miniature igniter development

    SciTech Connect (OSTI)

    Willkens, C.A.; Axelson, S.R.; Bateman, L.S.; Croucher, D.D.

    1996-09-01

    In 1988, Norton introduced its line of low-voltage 12- and 24-V miniature igniters made from a patented ceramic/intermetallic material. These igniters demonstrated superior strength and speed in a compact low-wattage assembly for gas-fired ignition. High-voltage igniters are being developed to complete the family of igniters for gas-fired ignition. These igniters have extremely low power requirements in the range of 50--100 W, are designed to operate at line voltages of 120 V, and are leading to designs for operation up to 230 V. These were developed using compositional and dimensional changes to the low voltage igniters. The 120 V igniter has exceeded 200,000 cycles in life testing and has been submitted for agency approval. These igniters are also undergoing field testing in various demanding gas-fired appliances. The evolution of the low-voltage igniter into the high-voltage model, as well as performance and material development issues are discussed.

  8. Data Analysis, Pre-Ignition Assessment, and Post-Ignition Modeling of the Large-Scale Annular Cookoff Tests

    SciTech Connect (OSTI)

    G. Terrones; F.J. Souto; R.F. Shea; M.W.Burkett; E.S. Idar

    2005-09-30

    In order to understand the implications that cookoff of plastic-bonded explosive-9501 could have on safety assessments, we analyzed the available data from the large-scale annular cookoff (LSAC) assembly series of experiments. In addition, we examined recent data regarding hypotheses about pre-ignition that may be relevant to post-ignition behavior. Based on the post-ignition data from Shot 6, which had the most complete set of data, we developed an approximate equation of state (EOS) for the gaseous products of deflagration. Implementation of this EOS into the multimaterial hydrodynamics computer program PAGOSA yielded good agreement with the inner-liner collapse sequence for Shot 6 and with other data, such as velocity interferometer system for any reflector and resistance wires. A metric to establish the degree of symmetry based on the concept of time of arrival to pin locations was used to compare numerical simulations with experimental data. Several simulations were performed to elucidate the mode of ignition in the LSAC and to determine the possible compression levels that the metal assembly could have been subjected to during post-ignition.

  9. National Ignition Facility & Photon Science HOW NIF WORKS

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    9 National Ignition Facility & Photon Science HOW NIF WORKS beam me up: how niF works In the National Ignition Facility (NIF), 192 laser beams travel a long path, about 1,500 meters, from their birth at the master oscillator-a device that generates the single pulse that seeds the entire NIF laser system-to the center of the target chamber. As the beams move through NIF's amplifiers, their energy increases exponentially. From beginning to end, the beams' total energy grows from one- billionth

  10. Ignition feedback regenerative free electron laser (FEL) amplifier

    DOE Patents [OSTI]

    Kim, Kwang-Je (Burr Ridge, IL); Zholents, Alexander (Walnut Creek, CA); Zolotorev, Max (Oakland, CA)

    2001-01-01

    An ignition feedback regenerative amplifier consists of an injector, a linear accelerator with energy recovery, and a high-gain free electron laser amplifier. A fraction of the free electron laser output is coupled to the input to operate the free electron laser in the regenerative mode. A mode filter in this loop prevents run away instability. Another fraction of the output, after suitable frequency up conversion, is used to drive the photocathode. An external laser is provided to start up both the amplifier and the injector, thus igniting the system.

  11. Stockpile Stewardship and the National Ignition Facility

    SciTech Connect (OSTI)

    Moses, E

    2012-01-04

    The National Ignition Facility (NIF), the world's most energetic laser system, is operational at Lawrence Livermore National Laboratory (LLNL). Since the completion of the construction project in March 2009, NIF has completed nearly 150 target experiments for the National Ignition Campaign (NIC), High Energy Density Stewardship Science (HEDSS) in the areas of radiation transport, material dynamics at high pressure in the solid state, as well as fundamental science and other national security missions. NIF capabilities and infrastructure are in place to support all of its missions with over 50 X-ray, optical and nuclear diagnostic systems and the ability to shoot cryogenic targets and DT layered capsules. NIF is now qualified for use of tritium and other special materials as well as to perform high yield experiments and classified experiments. DT implosions with record indirect-drive neutron yield of 4.5 x 10{sup 14} neutrons have been achieved. A series of 43 experiments were successfully executed over a 27-day period, demonstrating the ability to perform precise experiments in new regimes of interest to HEDSS. This talk will provide an update of the progress on the NIF capabilities, NIC accomplishments, as well as HEDSS and fundamental science experimental results and an update of the experimental plans for the coming year.

  12. Develop the dual fuel conversion system for high output, medium speed diesel engines. Quarterly report number 5, November 1997--January 1998

    SciTech Connect (OSTI)

    1998-02-23

    This quarter has the authors starting out with the engine mapped out in its standard dual fuel configuration. This means that the engine is configured to be exactly what the have been selling in the past. They have worked to install the new style gas injectors, Hydraulic power unit, control lines, gas lines and associated hardware. This hardware has been tested and is operational. They have been able to start at installing the spark ignition system but have been held up because of other more pressing work.

  13. The National Ignition Facility: The Path to Ignition, High Energy Density Science and Inertial Fusion Energy

    SciTech Connect (OSTI)

    Moses, E

    2011-03-25

    The National Ignition Facility (NIF) at the Lawrence Livermore National Laboratory (LLNL) in Livermore, CA, is a Nd:Glass laser facility capable of producing 1.8 MJ and 500 TW of ultraviolet light. This world's most energetic laser system is now operational with the goals of achieving thermonuclear burn in the laboratory and exploring the behavior of matter at extreme temperatures and energy densities. By concentrating the energy from its 192 extremely energetic laser beams into a mm{sup 3}-sized target, NIF can produce temperatures above 100 million K, densities of 1,000 g/cm{sup 3}, and pressures 100 billion times atmospheric pressure - conditions that have never been created in a laboratory and emulate those in the interiors of planetary and stellar environments. On September 29, 2010, NIF performed the first integrated ignition experiment which demonstrated the successful coordination of the laser, the cryogenic target system, the array of diagnostics and the infrastructure required for ignition. Many more experiments have been completed since. In light of this strong progress, the U.S. and the international communities are examining the implication of achieving ignition on NIF for inertial fusion energy (IFE). A laser-based IFE power plant will require a repetition rate of 10-20 Hz and a 10% electrical-optical efficiency laser, as well as further advances in large-scale target fabrication, target injection and tracking, and other supporting technologies. These capabilities could lead to a prototype IFE demonstration plant in 10- to 15-years. LLNL, in partnership with other institutions, is developing a Laser Inertial Fusion Energy (LIFE) baseline design and examining various technology choices for LIFE power plant This paper will describe the unprecedented experimental capabilities of the NIF, the results achieved so far on the path toward ignition, the start of fundamental science experiments and plans to transition NIF to an international user facility providing access to researchers around the world. The paper will conclude with a discussion of LIFE, its development path and potential to enable a carbon-free clean energy future.

  14. Stephanie Sparks | U.S. DOE Office of Science (SC)

    Office of Science (SC) Website

    Room 3H-051 U.S. Department of Energy 1000 Independence Avenue, SW Washington, D.C. 20585-1290 Email: stephanie.sparks@science.doe.gov Phone: 202-287-5245 Fax:...

  15. Particle Ignition and Char Combustion

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Ignition and Char Combustion - Sandia Energy Energy Search Icon Sandia Home Locations Contact Us Employee Locator Energy & Climate Secure & Sustainable Energy Future Stationary Power Energy Conversion Efficiency Solar Energy Wind Energy Water Power Supercritical CO2 Geothermal Natural Gas Safety, Security & Resilience of the Energy Infrastructure Energy Storage Nuclear Power & Engineering Grid Modernization Battery Testing Nuclear Fuel Cycle Defense Waste Management Programs

  16. Diagnostics for Fast Ignition Science

    SciTech Connect (OSTI)

    MacPhee, A; Akli, K; Beg, F; Chen, C; Chen, H; Clarke, R; Hey, D; Freeman, R; Kemp, A; Key, M; King, J; LePape, S; Link, A; Ma, T; Nakamura, N; Offermann, D; Ovchinnikov, V; Patel, P; Phillips, T; Stephens, R; Town, R; Wei, M; VanWoerkom, L; Mackinnon, A

    2008-05-06

    The concept for Electron Fast Ignition Inertial Confinement Fusion demands sufficient laser energy be transferred from the ignitor pulse to the assembled fuel core via {approx}MeV electrons. We have assembled a suite of diagnostics to characterize such transfer. Recent experiments have simultaneously fielded absolutely calibrated extreme ultraviolet multilayer imagers at 68 and 256eV; spherically bent crystal imagers at 4 and 8keV; multi-keV crystal spectrometers; MeV x-ray bremmstrahlung and electron and proton spectrometers (along the same line of sight); nuclear activation samples and a picosecond optical probe based interferometer. These diagnostics allow careful measurement of energy transport and deposition during and following laser-plasma interactions at extremely high intensities in both planar and conical targets. Augmented with accurate on-shot laser focal spot and pre-pulse characterization, these measurements are yielding new insight into energy coupling and are providing critical data for validating numerical PIC and hybrid PIC simulation codes in an area that is crucial for many applications, particularly fast ignition. Novel aspects of these diagnostics and how they are combined to extract quantitative data on ultra high intensity laser plasma interactions are discussed, together with implications for full-scale fast ignition experiments.

  17. Cray, AMPLab, NERSC Collaboration Targets Spark Performance on HPC

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Platforms Cray, AMPLab, NERSC Collaboration Targets Spark Performance on HPC Platforms Cray, AMPLab, NERSC Collaboration Targets Spark Performance on HPC Platforms November 4, 2015 Contact: Kathy Kincade, +1 510 495 2124, kkincade@lbl.gov As data-centric workloads become increasingly common in scientific and industrial applications, a pressing concern is how to design large-scale data analytics stacks that simplify analysis of the resulting data. A new collaboration between Cray, researchers

  18. High Power Laser Innovation Sparks Geothermal Power Potential | Department

    Office of Environmental Management (EM)

    of Energy High Power Laser Innovation Sparks Geothermal Power Potential High Power Laser Innovation Sparks Geothermal Power Potential May 29, 2015 - 11:02am Addthis The Energy Department's project partner Foro Energy lab tests a high power laser tool with a patented technology that could maximize heat recovery from geothermal wells. Source: Foro Energy. The Energy Department's project partner Foro Energy lab tests a high power laser tool with a patented technology that could maximize heat

  19. Effects of Ignition and Injection Perturbation under Lean and Dilute GDI Engine Operation

    SciTech Connect (OSTI)

    Wallner, Thomas; Kaul, Brian C; Sevik, James; Scarcelli, Riccardo; Wagner, Robert M

    2015-01-01

    Turbocharged gasoline direct injection (GDI) engines are quickly becoming more prominent in light-duty automotive applications because of their potential improvements in efficiency and fuel economy. While EGR dilute and lean operation serve as potential pathways to further improve efficiencies and emissions in GDI engines, they also pose challenges for stable engine operation. Tests were performed on a single-cylinder research engine that is representative of current automotive-style GDI engines. Baseline cases were performed under steady-state operating conditions where combustion phasing and dilution levels were varied to determine the effects on indicated efficiency and combustion stability. Sensitivity studies were then carried out by introducing binary low-high perturbation of spark timing and injection duration on a cycle-by-cycle basis under EGR dilute and lean operation to determine dominant feedback mechanisms. Ignition perturbation was phased early/late of MBT timing, and injection perturbation was set fuel rich/lean of the given air-to-fuel ratio. COVIMEP was used to define acceptable operation limits when comparing different perturbation cases. Overall sensitivity data shows COVIMEP is more sensitive to injection perturbation over ignition perturbation. This is because of the greater effect injection perturbation has on combustion phasing, ignition delay, and combustion duration.

  20. Safety analysis of optically ignited explosive and pyrotechnic devices

    SciTech Connect (OSTI)

    Merson, J.A.; Salas, F.J.; Holswade, S.

    1994-05-01

    The future of optical ordnance depends on the acceptance, validation and verification of the stated safety enhancement claims of optical ordnance over existing electrical explosive devices (EED`s). Sandia has been pursuing the development of optical ordnance, with the primary motivation of this effort being the enhancement of explosive safety by specifically reducing the potential of premature detonation that can occur with low energy electrically ignited explosive devices. By using semiconductor laser diodes for igniting these devices, safety improvements can be made without being detrimental to current system concerns since the inputs required for these devices are similar to electrical systems. Laser Diode Ignition (LDI) of the energetic material provides the opportunity to remove the bridgewire and electrically conductive pins from the charge cavity, creating a Faraday cage and thus isolating the explosive or pyrotechnic materials from stray electrical ignition sources. Recent results from our continued study of safety enhancements are presented. The areas of investigation which are presented include: (1) unintended optical source analysis, specifically lightning insensitivity, (2) electromagnetic radiation (EMR) and electrostatic discharge (ESD) insensitivity analysis, and (3) powder safety.

  1. Sandia Energy - Particle Ignition and Char Combustion

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    the top right shows a collection of streaks from injected particles as they ignite and burn while flowing upward. Figure 1. Schematic of Sandia's optical entrained flow reactor...

  2. Apparatus and method for tuned unsteady flow purging of high pulse rate spark gaps

    DOE Patents [OSTI]

    Thayer, III, William J. (Kent, WA)

    1990-01-01

    A spark gap switch apparatus is disclosed which is capable of operating at a high pulse rate which comprises an insulated housing; a pair of spaced apart electrodes each having one end thereof within a first bore formed in the housing and defining a spark gap therebetween; a pressure wave reflector in the first bore in the housing and spaced from the spark gap and capable of admitting purge flow; and a second enlarged bore contiguous with the first bore and spaced from the opposite side of the spark gap; whereby pressure waves generated during discharge of a spark across the spark gap will reflect off the wave reflector and back from the enlarged bore to the spark gap to clear from the spark gap hot gases residues generated during the discharge and simultaneously restore the gas density and pressure in the spark gap to its initial value.

  3. The Role of the Federal Project Director: Lessons from the National Ignition Facility

    Broader source: Energy.gov [DOE]

    The National Ignition Facility (NIF) Facility is home of the world’s largest laser.  With 192 laser beams that can deliver more than 60 times the energy of any previous laser system, NIF represents...

  4. Direct-driveignition designs with mid-Z ablators

    SciTech Connect (OSTI)

    Lafon, M.; Betti, R.; Anderson, K. S.; Collins, T. J. B.; Epstein, R.; McKenty, P. W.; Myatt, J. F.; Shvydky, A.; Skupsky, S.

    2015-03-15

    Achieving thermonuclear ignition using direct laser illumination relies on the capability to accelerate spherical shells to high implosion velocities while maintaining shell integrity. Ablator materials of moderate atomic number Z reduce the detrimental effects of laserplasma instabilities in direct-drive implosions. To validate the physics of moderate-Z ablator materials for ignition target designs on the National Ignition Facility (NIF), hydro-equivalent targets are designed using pure plastic (CH), high-density carbon, and glass (SiO{sub 2}) ablators. The hydrodynamic stability of these targets is investigated through two-dimensional (2D) single-mode and multimode simulations. The overall stability of these targets to laser-imprint perturbations and low-mode asymmetries makes it possible to design high-gain targets. Designs using polar-drive illumination are developed within the NIF laser system specifications. Mid-Z ablator targets are an attractive candidate for direct-drive ignition since they present better overall performance than plastic ablator targets through reduced laserplasma instabilities and a similar hydrodynamic stability.

  5. Fuel quantity modulation in pilot ignited engines

    DOE Patents [OSTI]

    May, Andrew

    2006-05-16

    An engine system includes a first fuel regulator adapted to control an amount of a first fuel supplied to the engine, a second fuel regulator adapted to control an amount of a second fuel supplied to the engine concurrently with the first fuel being supplied to the engine, and a controller coupled to at least the second fuel regulator. The controller is adapted to determine the amount of the second fuel supplied to the engine in a relationship to the amount of the first fuel supplied to the engine to operate in igniting the first fuel at a specified time in steady state engine operation and adapted to determine the amount of the second fuel supplied to the engine in a manner different from the relationship at steady state engine operation in transient engine operation.

  6. Light-Duty Reactivity Controlled Compression Ignition Drive Cycle...

    Office of Energy Efficiency and Renewable Energy (EERE) Indexed Site

    Light-Duty Reactivity Controlled Compression Ignition Drive Cycle Fuel Economy and Emissions Estimates Light-Duty Reactivity Controlled Compression Ignition Drive Cycle Fuel ...

  7. Physics of compact ignition tokamak designs

    SciTech Connect (OSTI)

    Singer, C.E.; Ku, L.P.; Bateman, G.; Seidl, F.; Sugihara, M.

    1986-03-01

    Models for predicting plasma performance in compact ignition experiments are constructed on the basis of theoretical and empirical constraints and data from tokamak experiments. Emphasis is placed on finding transport and confinement models which reproduce results of both ohmically and auxiliary heated tokamak data. Illustrations of the application of the models to compact ignition designs are given.

  8. Education Highlights: Gasoline Compression Ignition | Argonne National

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Laboratory Education Highlights: Gasoline Compression Ignition Share Description Argonne intern Kendyl Partridge from Mississippi State University worked with Argonne mentor Steve Ciatti in studying gasoline compression ignition engines. This research will help engineers increase an engine's efficiency while reducing its environmental impact. Speakers Kendyl Partridge, Argonne National Laboratory Intern from Mississippi State University Duration 1:56 Topic Energy Energy efficiency Vehicles

  9. Lean-Burn Stationary Natural Gas Reciprocating Engine Operation with a Prototype Miniature Diode Side Pumped Passively Q-switched Laser Spark Plug

    SciTech Connect (OSTI)

    McIntyre, D.L.; Woodruff, S.D.; McMillian, M.H.; Richardson, S.W.; Gautam, Mridul

    2008-04-01

    To meet the ignition system needs of large bore lean burn stationary natural gas engines a laser diode side pumped passively Q-switched laser igniter was developed and used to ignite lean mixtures in a single cylinder research engine. The laser design was produced from previous work. The in-cylinder conditions and exhaust emissions produced by the miniaturized laser were compared to that produced by a laboratory scale commercial laser system used in prior engine testing. The miniaturized laser design as well as the combustion and emissions data for both laser systems was compared and discussed. It was determined that the two laser systems produced virtually identical combustion and emissions data.

  10. Fuel Cell Startup Could Spark A Revolution | GE Global Research

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Fuel Cell Startup Could Spark a Revolution Click to email this to a friend (Opens in new window) Share on Facebook (Opens in new window) Click to share (Opens in new window) Click to share on LinkedIn (Opens in new window) Click to share on Tumblr (Opens in new window) Fuel Cell Startup Could Spark a Revolution A fuel cell works like a battery, using a simple chemical reaction to provide energy. In fuel cells, this reaction involves hydrogen molecules abundant in natural gas and oxygen from

  11. ArcSafe® with Pulsed Arrested Spark Discharge

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    ArcSafe® with Pulsed Arrested Spark Discharge  2007 R&D 100 Award Entry Form ArcSafe® with Pulsed Arrested Spark Discharge  Joint Submitters Submitting Organization Sandia National Laboratories PO Box 5800, MS 1181 Albuquerque, NM 87185-1181 USA Larry Schneider Phone: (505) 845-7135 Fax: (505) 845-7685 Email: lxschne@sandia.gov AFFIRMATION: I affirm that all information submitted as a part of, or supplemental to, this entry is a fair and accurate represen- tation of this product.

  12. Calling All Majors: Sparking Clean Energy Interest from Students in

    Office of Energy Efficiency and Renewable Energy (EERE) Indexed Site

    Washington | Department of Energy Calling All Majors: Sparking Clean Energy Interest from Students in Washington Calling All Majors: Sparking Clean Energy Interest from Students in Washington November 6, 2014 - 3:55pm Addthis Students in Western Washington University’s spring 2013 “Applications in Energy Production” course get an up-close view of how energy is generated. | Photo: Courtesy of Chris Linder, Western Washington University. Students in Western Washington

  13. The Application of High Energy Ignition and Boosting/Mixing Technology to Increase Fuel Economy in Spark Ignition Gasoline Engines by Increasing EGR Dilution Capability

    Broader source: Energy.gov [DOE]

    2013 DOE Hydrogen and Fuel Cells Program and Vehicle Technologies Program Annual Merit Review and Peer Evaluation Meeting

  14. A historical analysis of the co-evolution of gasoline octane number and spark-ignition engines

    DOE Public Access Gateway for Energy & Science Beta (PAGES Beta)

    Splitter, Derek A.; Pawlowski, Alex E.; Wagner, Robert M.

    2016-01-01

    In this work, the authors reviewed engine, vehicle, and fuel data since 1925 to examine the historical and recent coupling of compression ratio and fuel antiknock properties (i.e., octane number) in the U.S. light-duty vehicle market. The analysis identified historical timeframes, trends, and illustrated how three factors: consumer preferences, technical capabilities, and regulatory legislation, affect personal mobility. Data showed that throughout history these three factors have a complex and time sensitive interplay. Long term trends in the data were identified where interaction and evolution between all three factors was observed. Specifically, transportation efficiency per unit power (gal/ton-mi/hp) was found tomore » be a good metric to integrate technical, societal, and regulatory effects into the evolutional pathway of personal mobility. From this framework, discussions of future evolutionary changes to personal mobility are also presented.« less

  15. Final report for miniature laser ignited bellows motor

    SciTech Connect (OSTI)

    Renfro, S.L.

    1994-02-18

    A miniature optically ignited actuation device has been demonstrated using a laser diode as an ignition source. This pyrotechnic driven motor provides between 4 and 6 lbs of linear force across a 0.090 inch diameter surface. The physical envelope of the device is 1/2 inch long and 1/8 inch diameter. This unique application of optical energy can be used as a mechanical link in optical arming systems or other applications where low shock actuation is desired and space is limited. An analysis was performed to determine pyrotechnic materials suitable to actuate a bellows device constructed of aluminum or stainless steel. The aluminum bellows was chosen for further development and several candidate pyrotechnics were evaluated. The velocity profile and delivered force were quantified using an non-intrusive optical motion sensor.

  16. Princeton Plasma Physics Lab - National Ignition Facility

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Feb 2013 14:30:50 +0000 jgreenwa 1361 at http:www.pppl.gov National Ignition Facility (NIF): Under Pressure: Ramp-Compression Smashes Record http:www.pppl.govnode248

  17. lasers. National Ignition Facility | National Nuclear Security...

    National Nuclear Security Administration (NNSA)

    target shot of fiscal year 2015 WASHINGTON - Last week, the National Ignition Facility (NIF) fired its 300th laser target shot in fiscal year (FY) 2015, meeting the year's goal...

  18. Low jitter spark gap switch for repetitively pulsed parallel capacitor banks

    SciTech Connect (OSTI)

    Rohwein, G. J.

    1980-01-01

    A two-section air insulated spark gap has been developed for switching multi-kilojoule plus-minus charged parallel capacitor banks which operate continuously at pulse rates up to 20 pps. The switch operates with less than 2 ns jitter, recovers its dielectric strength within 2 to 5 ms and has not shown degraded performance in sequential test runs totaling over a million shots. Its estimated life with copper electrodes is > 10/sup 7/ shots. All preliminary tests indicate that the switch is suitable for continuous running multi-kilojoule systems operating to at least 20 pps.

  19. National Ignition Facility & Photon Science

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    9 National Ignition Facility & Photon Science a new era of science a new era of experimental science laboratory experiments at the National Ignition Facility will enable researchers for the first time to study the effects on matter of extreme temperatures, pressures, and densities that exist naturally only in stars and deep inside planets. Results from this relatively new field of research, known as high-energy- density (hed) science, will mark the dawn of a new era of experimental science.

  20. Confinement scaling and ignition in tokamaks

    SciTech Connect (OSTI)

    Perkins, F.W.; Sun, Y.C.

    1985-10-01

    A drift wave turbulence model is used to compute the scaling and magnitude of central electron temperature and confinement time of tokamak plasmas. The results are in accord with experiment. Application to ignition experiments shows that high density (1 to 2) . 10/sup 15/ cm/sup -3/, high field, B/sub T/ > 10 T, but low temperature T approx. 6 keV constitute the optimum path to ignition.

  1. Ignition methods and apparatus using microwave energy

    DOE Patents [OSTI]

    DeFreitas, Dennis Michael; Migliori, Albert

    1997-01-01

    An ignition apparatus for a combustor includes a microwave energy source that emits microwave energy into the combustor at a frequency within a resonant response of the combustor, the combustor functioning as a resonant cavity for the microwave energy so that a plasma is produced that ignites a combustible mixture therein. The plasma preferably is a non-contact plasma produced in free space within the resonant cavity spaced away from with the cavity wall structure and spaced from the microwave emitter.

  2. Loss/gain on ignition test report

    SciTech Connect (OSTI)

    Winstead, M.L.

    1996-01-10

    Document provides the results of tests done on Product Cans from the HC-21C sludge stabilization process. Tests included running a simulated Thermogravimetric Analysis, TGA, on the processed material that have received Loss On Ignition (LOI) sample results that show a gain on ignition or a high LOI and reprocessing product cans with high LOIs. Also, boat material temperatures in the furnace were tracked during the testing.

  3. Infrared Thermographic Study of Laser Ignition

    SciTech Connect (OSTI)

    Mohler, Jonathan H.; Chow, Charles T. S.

    1986-07-01

    Pyrotechnic ignition has been studied in the past by making a limited number of discrete temperature-time observations during ignition. Present-day infrared scanning techniques make it possible to record thermal profiles, during ignition, with high spacial and temporal resolution. Data thus obtained can be used with existing theory to characterize pyrotechnic materials and to develop more precise kinetic models of the ignition process. Ignition has been studied theoretically and experimentally using various thermal methods. It has been shown that the whole process can, ideally, be divided into two stages. In the first stage, the sample pellet behaves like an inert body heated by an external heat source. The second stage is governed by the chemical reaction in the heated volume produced during the first stage. High speed thermographic recording of the temperature distribution in the test sample during laser ignition makes it possible to calculate the heat content at any instant. Thus, one can actually observe laser heating and the onset of self-sustained combustion in the pellet. The experimental apparatus used to make these observations is described. The temperature distributions recorded are shown to be in good agreement with those predicted by heat transfer theory. Heat content values calculated from the observed temperature distributions are used to calculate thermal and kinetic parameters for several samples. These values are found to be in reasonable agreement with theory.

  4. Infrared thermographic study of laser ignition

    SciTech Connect (OSTI)

    Mohler, J.H.; Chow, C.T.S.

    1986-07-21

    Pyrotechnic ignition has been studied in the past by making a limited number of discrete temperature-time observations during ignition. Present-day infrared scanning techniques make it possible to record thermal profiles, during ignition, with high spacial and temporal resolution. Data thus obtained can be used with existing theory to characterize pyrotechnic materials and to develop more precise kinetic models of the ignition process. Ignition has been studied theoretically and experimentally using various thermal methods. It has been shown that the whole process can, ideally, be divided into two stages. In the first stage, the sample pellet behaves like an inert body heated by an external heat source. The second stage is governed by the chemical reaction in the heated volume produced during the first stage. High speed thermographic recording of the temperature distribution in the test sample during laser ignition makes it possible to calculate the heat content at any instant. Thus, one can actually observe laser heating and the onset of self-sustained combustion in the pellet.

  5. Measurements of the Radiated Fields and Conducted Current Leakage from the Pulsed Power Systems in the National Ignition Facility at LLNL

    SciTech Connect (OSTI)

    Anderson, R A; Clancy, T J; Fulkerson, S; Petersen, D; Pendelton, D; Hulsey, S; Ullery, G; Tuck, J; Polk, M; Kamm, R; Newton, M; Moore, W B; Arnold, P; Ollis, C; Hinz, A; Robb, C; Fornes, J; Watson, J

    2003-07-31

    An important pulsed power system consideration is that they inherently generate fields and currents that can cause interference in other subsystems and diagnostics. Good pulsed power design, grounding and isolation practices can help mitigate these unwanted signals. During the laser commissioning shots for the NIF Early Light milestone at LLNL, measurements were made of the radiated field and conducted currents caused by the Power Conditioning System (PCS) modules with flash lamp load and the Plasma Electrode Pockels Cell (PEPC) driver. The measurements were made in the capacitor bay, laser bay, control room and target bay. The field measurements were made with B-dot and E-dot probes with bandwidth of about 100MHz. The current measurements were made with a clamp on probe with a bandwidth of about 20 MHz. The results of these measurements show fields and currents in the NIF Facility well below that required for interference with other subsystems. Currents on the target chamber from the pulsed power systems are well below the background noise currents.

  6. Submission of Notice of Termination of Coverage Under the National Pollutant Discharge Elimination System General Permit No. CAS000002 for WDID No. 201C349114, Lawrence Livermore National Laboratory Ignition Facility Construction Project

    SciTech Connect (OSTI)

    Brunckhorst, K

    2009-04-21

    This is the completed Notice of Termination of Coverage under the General Permit for Storm Water Discharges Associated with Construction Activity. Construction activities at the National Ignition Facility Construction Project at Lawrence Livermore National Laboratory are now complete. The Notice of Termination includes photographs of the completed construction project and a vicinity map.

  7. Neutron time-of-flight and emission time diagnostics for the National Ignition Facility

    SciTech Connect (OSTI)

    Murphy, T. J.; Jimerson, J. L.; Berggren, R. R.; Faulkner, J. R.; Oertel, J. A.; Walsh, P. J.

    2001-01-01

    Current plans call for a system of current mode neutron detectors for the National Ignition Facility for extending the range of neutron yields below that of the neutron activation system, for ion-temperature measurements over a wide yield range, and for determining the average neutron emission time. The system will need to operate over a yield range of 10{sup 6} for the lowest-yield experiments to 10{sup 19} for high-yield ignited targets. The requirements will be satisfied using several detectors located at different distances from the target. This article presents a conceptual design for the NIF nToF system.

  8. National Ignition Facility Comes to Life

    SciTech Connect (OSTI)

    Moses, E

    2003-09-01

    First conceived of nearly 15 years ago, the National Ignition Facility (NIF) is up and running and successful beyond almost everyone's expectations. During commissioning of the first four laser beams, the laser system met design specifications for everything from beam quality to energy output. NIF will eventually have 192 laser beams. Yet with just 2% of its final beam configuration complete, NIF has already produced the highest energy laser shots in the world. In July, laser shots in the infrared wavelength using four beams produced a total of 26.5 kilojoules of energy per beam, not only meeting NIF's design energy requirement of 20 kilojoules per beam but also exceeding the energy of any other infrared laser beamline. In another campaign, NIF produced over 11.4 kilojoules of energy when the infrared light was converted to green light. An earlier performance campaign of laser light that had been frequency converted from infrared to ultraviolet really proved NIF's mettle. Over 10.4 kilojoules of ultraviolet energy were produced in about 4 billionths of a second. If all 192 beamlines were to operate at these levels, over 2 megajoules of energy would result. That much energy for the pulse duration of several nanoseconds is about 500 trillion watts of power, more than 500 times the US peak generating power.

  9. Focused shock spark discharge drill using multiple electrodes

    DOE Patents [OSTI]

    Moeny, William M. (Albuquerque, NM); Small, James G. (Albuquerque, NM)

    1988-01-01

    A spark discharge focused drill provided with one pulse forming line or a number of pulse forming lines. The pulse forming line is connected to an array of electrodes which would form a spark array. One of the electrodes of each of the array is connected to the high voltage side of the pulse forming line and the other electrodes are at ground potential. When discharged in a liquid, these electrodes produce intense focused shock waves that can pulverize or fracture rock. By delaying the firing of each group of electrodes, the drill can be steered within the earth. Power can be fed to the pulse forming line either downhole or from the surface area. A high voltage source, such as a Marx generator, is suitable for pulse charging the lines.

  10. Hour of Code sparks interest in computer science

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    STEM skills Community Connections: Your link to news and opportunities from Los Alamos National Laboratory Latest Issue:Mar. 2016 all issues All Issues » submit Hour of Code sparks interest in computer science Taking the mystery out of programming February 1, 2016 Hour of Code participants work their way through fun computer programming tutorials. Hour of Code participants work their way through fun computer programming tutorials. Contacts Community Programs Director Kathy Keith Email Editor

  11. Analytical model for fast-shock ignition

    SciTech Connect (OSTI)

    Ghasemi, S. A. Farahbod, A. H.; Sobhanian, S.

    2014-07-15

    A model and its improvements are introduced for a recently proposed approach to inertial confinement fusion, called fast-shock ignition (FSI). The analysis is based upon the gain models of fast ignition, shock ignition and considerations for the fast electrons penetration into the pre-compressed fuel to examine the formation of an effective central hot spot. Calculations of fast electrons penetration into the dense fuel show that if the initial electron kinetic energy is of the order ?4.5 MeV, the electrons effectively reach the central part of the fuel. To evaluate more realistically the performance of FSI approach, we have used a quasi-two temperature electron energy distribution function of Strozzi (2012) and fast ignitor energy formula of Bellei (2013) that are consistent with 3D PIC simulations for different values of fast ignitor laser wavelength and coupling efficiency. The general advantages of fast-shock ignition in comparison with the shock ignition can be estimated to be better than 1.3 and it is seen that the best results can be obtained for the fuel mass around 1.5 mg, fast ignitor laser wavelength ?0.3??micron and the shock ignitor energy weight factor about 0.25.

  12. Ignition of THKP and TKP pyrotechnic powders :

    SciTech Connect (OSTI)

    Maharrey, Sean P.; Erikson, William W; Highley, Aaron M.; Wiese-Smith, Deneille; Kay, Jeffrey J

    2014-03-01

    We have conducted Simultaneous Thermogravimetric Modulated Beam Mass Spectrometry (STMBMS) experiments on igniter/actuator pyrotechnic powders to characterize the reactive processes controlling the ignition and combustion behavior of these materials. The experiments showed a complex, interactive reaction manifold involving over ten reaction pathways. A reduced dimensionality reaction manifold was developed from the detailed 10-step manifold and is being incorporated into existing predictive modeling codes to simulate the performance of pyrotechnic powders for NW component development. The results from development of the detailed reaction manifold and reduced manifold are presented. The reduced reaction manifold has been successfully used by SNL/NM modelers to predict thermal ignition events in small-scale testing, validating our approach and improving the capability of predictive models.

  13. Ignition of deuterium-tritium fuel targets

    DOE Patents [OSTI]

    Musinski, D.L.; Mruzek, M.T.

    1991-08-27

    Disclosed is a method of igniting a deuterium-tritium ICF fuel target to obtain fuel burn in which the fuel target initially includes a hollow spherical shell having a frozen layer of DT material at substantially uniform thickness and cryogenic temperature around the interior surface of the shell. The target is permitted to free-fall through a target chamber having walls heated by successive target ignitions, so that the target is uniformly heated during free-fall to at least partially melt the frozen fuel layer and form a liquid single-phase layer or a mixed liquid/solid bi-phase layer of substantially uniform thickness around the interior shell surface. The falling target is then illuminated from exteriorly of the chamber while the fuel layer is at substantially uniformly single or bi-phase so as to ignite the fuel layer and release energy therefrom. 5 figures.

  14. Ignition of deuterium-trtium fuel targets

    DOE Patents [OSTI]

    Musinski, Donald L. (Saline, MI); Mruzek, Michael T. (Britton, MI)

    1991-01-01

    A method of igniting a deuterium-tritium ICF fuel target to obtain fuel burn in which the fuel target initially includes a hollow spherical shell having a frozen layer of DT material at substantially uniform thickness and cryogenic temperature around the interior surface of the shell. The target is permitted to free-fall through a target chamber having walls heated by successive target ignitions, so that the target is uniformly heated during free-fall to at least partially melt the frozen fuel layer and form a liquid single-phase layer or a mixed liquid/solid bi-phase layer of substantially uniform thickness around the interior shell surface. The falling target is then illuminated from exteriorly of the chamber while the fuel layer is at substantially uniformly single or bi-phase so as to ignite the fuel layer and release energy therefrom.

  15. National Ignition Facility project acquisition plan revision 1

    SciTech Connect (OSTI)

    Clobes, A.R.

    1996-10-01

    The purpose of this National Ignition Facility Acquisition Plan is to describe the overall procurement strategy planned for the National Ignition Facility M Project. It was prepared for the NIP Prood Office by the NIF Procurement Manager.

  16. Gas turbine igniter with ball-joint support

    SciTech Connect (OSTI)

    Steber, C.E.; Travis, R.J.; Rizzo, J.A.

    1990-02-27

    This patent describes a support for an igniter for a combustor of a gas turbine, the combustor being of a type including a casing and a liner within the casing. It comprises: a ball joint; means for supporting the ball joint disposed a substantial distance outward from the casing; a body section of the igniter affixed in the ball joint; means for permitting the ball joint, and the body section to rotate through a substantial range; an igniter tip on the body section; and a hole in the liner. The igniter tip entering through the hole and into an interior of the liner. The hole being a tight fit to the igniter tip, whereby leakage past the igniter tip through the hole is limited. The substantial range being sufficient to permit fitting the igniter tip in the hole in the presence of manufacturing tolerances, and to permit the igniter tip to track the hole in the presence of differential thermal expansion during operation.

  17. "New Results from the National Ignition Facility", Dr. John Lindl...

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    goal of 1.8 MJ and 500 TW of ultraviolet light in 2012. The Ignition Campaign on the NIF is making steady progress toward achieving ignition. Utilizing precision...

  18. National Ignition Facility & Photon Science

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    5 National Ignition Facility & Photon Science how do Lasers work? how Do Lasers work? A laser can be as small as a microscopic computer chip or as immense as the National Ignition Facility (NIF), which is three football fields wide. Clearly size has nothing to do with what makes a laser. "laser" is an acronym for light amplification by stimulated emission of radiation. If the electrons in special glasses, crystals, or gases are energized, they will emit light photons in response to

  19. Combustion, Efficiency, and Fuel Effects in a Spark-Assisted HCCI Gasoline

    Office of Energy Efficiency and Renewable Energy (EERE) Indexed Site

    Engine | Department of Energy Combustion, Efficiency, and Fuel Effects in a Spark-Assisted HCCI Gasoline Engine Combustion, Efficiency, and Fuel Effects in a Spark-Assisted HCCI Gasoline Engine 2004 Diesel Engine Emissions Reduction (DEER) Conference Presentation: Oak Ridge National Laboratory, Fuel, Engines, and Emissions Research Center PDF icon 2004_deer_bunting2.pdf More Documents & Publications Enabling and Expanding HCCI in PFI Gasoline Engines with High EGR and Spark Assist

  20. Controlling And Operating Homogeneous Charge Compression Ignition (Hcci) Engines

    DOE Patents [OSTI]

    Flowers, Daniel L. (San Leandro, CA)

    2005-08-02

    A Homogeneous Charge Compression Ignition (HCCI) engine system includes an engine that produces exhaust gas. A vaporization means vaporizes fuel for the engine an air induction means provides air for the engine. An exhaust gas recirculation means recirculates the exhaust gas. A blending means blends the vaporized fuel, the exhaust gas, and the air. An induction means inducts the blended vaporized fuel, exhaust gas, and air into the engine. A control means controls the blending of the vaporized fuel, the exhaust gas, and the air and for controls the inducting the blended vaporized fuel, exhaust gas, and air into the engine.

  1. FIREBALL: Fusion Ignition Rocket Engine with Ballistic Ablative Lithium Liner

    SciTech Connect (OSTI)

    Martin, Adam K.; Eskridge, Richard H.; Lee, Michael H.; Fimognari, Peter J.

    2006-01-20

    Thermo-nuclear fusion may be the key to a high Isp, high specific power propulsion system. In a fusion system energy is liberated within, and imparted directly to, the propellant. In principle, this can overcome the performance limitations inherent in systems that require thermal power transfer across a material boundary, and/or multiple power conversion stages (NTR, NEP). A thermo-nuclear propulsion system, which attempts to overcome some of the problems inherent in the Orion concept, is described. A dense FRC plasmoid is accelerated to high velocity (in excess of 500 km/s) and is compressed into a detached liner (pulse unit). The kinetic energy of the FRC is converted into thermal and magnetic-field energy, igniting a fusion burn in the magnetically confined plasma. The fusion reaction serves as an ignition source for the liner, which is made out of detonable materials. The energy liberated in this process is converted to thrust by a pusher-plate, as in the classic Orion concept. However with this concept, the vehicle does not carry a magazine of autonomous pulse-units. By accelerating a second, heavier FRC, which acts as a piston, right behind the first one, the velocity required to initiate the fusion burn is greatly reduced.

  2. National Ignition Facility Title II Design Plan

    SciTech Connect (OSTI)

    Kumpan, S

    1997-03-01

    This National Ignition Facility (NIF) Title II Design Plan defines the work to be performed by the NIF Project Team between November 1996, when the U.S. Department of Energy (DOE) reviewed Title I design and authorized the initiation of Title H design and specific long-lead procurements, and September 1998, when Title 11 design will be completed.

  3. Deliberate ignition of hydrogen-air-steam mixtures in condensing steam environments

    SciTech Connect (OSTI)

    Blanchat, T.K.; Stamps, D.W.

    1997-05-01

    Large scale experiments were performed to determine the effectiveness of thermal glow plug igniters to burn hydrogen in a condensing steam environment due to the presence of water sprays. The experiments were designed to determine if a detonation or accelerated flame could occur in a hydrogen-air-steam mixture which was initially nonflammable due to steam dilution but was rendered flammable by rapid steam condensation due to water sprays. Eleven Hydrogen Igniter Tests were conducted in the test vessel. The vessel was instrumented with pressure transducers, thermocouple rakes, gas grab sample bottles, hydrogen microsensors, and cameras. The vessel contained two prototypic engineered systems: (1) a deliberate hydrogen ignition system and (2) a water spray system. Experiments were conducted under conditions scaled to be nearly prototypic of those expected in Advanced Light Water Reactors (such as the Combustion Engineering (CE) System 80+), with prototypic spray drop diameter, spray mass flux, steam condensation rates, hydrogen injection flow rates, and using the actual proposed plant igniters. The lack of any significant pressure increase during the majority of the burn and condensation events signified that localized, benign hydrogen deflagration(s) occurred with no significant pressure load on the containment vessel. Igniter location did not appear to be a factor in the open geometry. Initially stratified tests with a stoichiometric mixture in the top showed that the water spray effectively mixes the initially stratified atmosphere prior to the deflagration event. All tests demonstrated that thermal glow plugs ignite hydrogen-air-steam mixtures under conditions with water sprays near the flammability limits previously determined for hydrogen-air-steam mixtures under quiescent conditions. This report describes these experiments, gives experimental results, and provides interpretation of the results. 12 refs., 127 figs., 16 tabs.

  4. Dual nozzle single pump fuel injection system

    SciTech Connect (OSTI)

    Gonzalez, C.

    1992-02-25

    This patent describes an improvement in a fuel injection system in a stratified charge hybrid internal combustion engine including a main combustion chamber, a precombustion chamber connected with the main chamber, fuel injectors in the main combustion chamber and precombustion chamber which open at higher and lower pressure levels respectively to sequentially inject fuel into the prechamber and the main chamber, timed spark ignition means in the prechamber for ignition of the fuel-air mixture therein, and an engine driven and timed fuel injection pump having a variable output capacity that varies with power level position, the injection pump is supplied by a low pressure charging pump. The improvement comprises: a shuttle valve including a bore therein; a shuttle spool means positioned within the bore defining a prechamber supply chamber on one side thereof and a spool activation chamber on the opposite side thereof the spool means having a first and second position; biasing means urging the spool towards it first position with the spool actuation chamber at its minimum volume; first conduit means connecting charging pressure to the prechamber supply camber in the first position oil the spool means; second conduit means connecting the injection pump to spool actuation chamber; third conduit means connecting the spool actuating chamber with the main injector; forth conduit means connecting the prechamber supply chamber with the prechamber injector; the initial charge from the injection pump actuates the spool means from its fir to its second position.

  5. Low pressure spark gap triggered by an ion diode

    DOE Patents [OSTI]

    Prono, Daniel S. (Livermore, CA)

    1985-01-01

    Spark gap apparatus for use as an electric switch operating at high voltage, high current and high repetition rate. Mounted inside a housing are an anode, cathode and ion plate. An ionizable fluid is pumped through the chamber of the housing. A pulse of current to the ion plate causes ions to be emitted by the ion plate, which ions move into and ionize the fluid. Electric current supplied to the anode discharges through the ionized fluid and flows to the cathode. Current stops flowing when the current source has been drained. The ionized fluid recombines into its initial dielectric ionizable state. The switch is now open and ready for another cycle.

  6. Experimental and Computational Study of Nonpremixed Ignition of Dimethyl Ether in Counterflow

    SciTech Connect (OSTI)

    Zheng, X L; Lu, T F; Law, C K; Westbrook, C K

    2003-12-19

    The ignition temperature of nitrogen-diluted dimethyl ether (DME) by heated air in counterflow was experimentally determined for DME concentration from 5.9 to 30%, system pressure from 1.5 to 3.0 atmospheres, and pressure-weighted strain rate from 110 to 170/s. These experimental data were compared with two mechanisms that were respectively available in 1998 and 2003, with the latter being a substantially updated version of the former. The comparison showed that while the 1998-mechanism uniformly over-predicted the ignition temperature, the 2003-mechanism yielded surprisingly close agreement for all experimental data. Sensitivity analysis for the near-ignition state based on both mechanisms identified the deficiencies of the 1998-mechanism, particularly the specifics of the low-temperature cool flame chemistry in effecting ignition at higher temperatures, as the fuel stream is being progressively heated from its cold boundary to the high-temperature ignition region around the hot-stream boundary. The 2003-mechanism, consisting of 79 species and 398 elementary reactions, was then systematically simplified by using the directed relation graph method to a skeletal mechanism of 49 species and 251 elementary reactions, which in turn was further simplified by using computational singular perturbation method and quasi-steady-state species assumption to a reduced mechanism consisting of 33 species and 28 lumped reactions. It was demonstrated that both the skeletal and reduced mechanisms mimicked the performance of the detailed mechanism with high accuracy.

  7. SolarBridge Technologies formerly SmartSpark Energy Systems ...

    Open Energy Info (EERE)

    Texas Zip: 78731 Sector: Solar Product: Developing a micro-inverter for residential solar panels, and charge equalisers to improve life for battery-powered equipment....

  8. A study of the ignition processes in a center-hole-fired thermal battery

    SciTech Connect (OSTI)

    Guidotti, R.A.; Reinhardt, F.W.

    1998-04-01

    The ignition processes that take place during activation of a 16 cell, center hole fired thermal battery were examined by monitoring the voltage of each cell during activation. The average rise time of each cell to a voltage of 1.125 V was determined for the LiSi/LiCl-LiBr-LiF/FeS{sub 2} electrochemical system. The effects of heat pellet composition, center hole diameter, and the load on the activation parameters were examined for three different igniters. A large variability in individual cell performance was evident along with cell reversal, depending on the location of the cell in the stack. It was not possible to draw detailed statistical information of the relative ignition sequence due to the intrinsic large scatter in the data.

  9. The ePLAS Code for Ignition Studies

    SciTech Connect (OSTI)

    Mason, Rodney J

    2012-09-20

    Inertial Confinement Fusion (ICF) presents unique opportunities for the extraction of clean energy from Fusion. Intense lasers and particle beams can create and interact with such plasmas, potentially yielding sufficient energy to satisfy all our national needs. However, few models are available to help aid the scientific community in the study and optimization of such interactions. This project enhanced and disseminated the computer code ePLAS for the early understanding and control of Ignition in ICF. ePLAS is a unique simulation code that tracks the transport of laser light to a target, the absorption of that light resulting in the generation and transport of hot electrons, and the heating and flow dynamics of the background plasma. It uses an implicit electromagnetic field-solving method to greatly reduce computing demands, so that useful target interaction studies can often be completed in 15 minutes on a portable 2.1 GHz PC. The code permits the rapid scoping of calculations for the optimization of laser target interactions aimed at fusion. Recent efforts have initiated the use of analytic equations of state (EOS), K-alpha image rendering graphics, allocatable memory for source-free usage, and adaption to the latest Mac and Linux Operating Systems. The speed and utility of ePLAS are unequaled in the ICF simulation community. This project evaluated the effects of its new EOSs on target heating, compared fluid and particle models for the ions, initiated the simultaneous use of both ion models in the code, and studied long time scale 500 ps hot electron deposition for shock ignition. ePLAS has been granted EAR99 export control status, permitting export without a license to most foreign countries. Beta-test versions of ePLAS have been granted to several Universities and Commercial users. The net Project was aimed at achieving early success in the laboratory ignition of thermonuclear targets and the mastery of controlled fusion power for the nation.

  10. The National Ignition Facility: The Path to a Carbon-Free Energy Future

    SciTech Connect (OSTI)

    Stolz, C J

    2011-03-16

    The National Ignition Facility (NIF), the world's largest and most energetic laser system, is now operational at Lawrence Livermore National Laboratory (LLNL). The NIF will enable exploration of scientific problems in national strategic security, basic science and fusion energy. One of the early NIF goals centers on achieving laboratory-scale thermonuclear ignition and energy gain, demonstrating the feasibility of laser fusion as a viable source of clean, carbon-free energy. This talk will discuss the precision technology and engineering challenges of building the NIF and those we must overcome to make fusion energy a commercial reality.

  11. Method and apparatus for electrical cable testing by pulse-arrested spark discharge

    DOE Patents [OSTI]

    Barnum, John R. (Albuquerque, NM); Warne, Larry K. (Albuquerque, NM); Jorgenson, Roy E. (Albuquerque, NM); Schneider, Larry X. (Albuquerque, NM)

    2005-02-08

    A method for electrical cable testing by Pulse-Arrested Spark Discharge (PASD) uses the cable response to a short-duration high-voltage incident pulse to determine the location of an electrical breakdown that occurs at a defect site in the cable. The apparatus for cable testing by PASD includes a pulser for generating the short-duration high-voltage incident pulse, at least one diagnostic sensor to detect the incident pulse and the breakdown-induced reflected and/or transmitted pulses propagating from the electrical breakdown at the defect site, and a transient recorder to record the cable response. The method and apparatus are particularly useful to determine the location of defect sites in critical but inaccessible electrical cabling systems in aging aircraft, ships, nuclear power plants, and industrial complexes.

  12. Test report for core drilling ignitability testing

    SciTech Connect (OSTI)

    Witwer, K.S.

    1996-08-08

    Testing was carried out with the cooperation of Westinghouse Hanford Company and the United States Bureau of Mines at the Pittsburgh Research Center in Pennsylvania under the Memorandum of Agreement 14- 09-0050-3666. Several core drilling equipment items, specifically those which can come in contact with flammable gasses while drilling into some waste tanks, were tested under conditions similar to actual field sampling conditions. Rotary drilling against steel and rock as well as drop testing of several different pieces of equipment in a flammable gas environment were the specific items addressed. The test items completed either caused no ignition of the gas mixture, or, after having hardware changes or drilling parameters modified, produced no ignition in repeat testing.

  13. National Ignition Facility & Photon Science

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    security maintaining the nuclear weapons stockpile As the largest, highest-energy laser ever built, the National Ignition Facility (NIF) can create conditions in the laboratory-temperatures of 100 million degrees and pressures 100 billion times that of the earth's atmosphere-similar to those in stars and nuclear weapons. NIF is the only facility that can perform controlled, experimental studies of thermonuclear burn, the phenomenon that gives rise to the immense energy of modern nuclear weapons.

  14. Multiple laser pulse ignition method and apparatus

    DOE Patents [OSTI]

    Early, James W. (Los Alamos, NM)

    1998-01-01

    Two or more laser light pulses with certain differing temporal lengths and peak pulse powers can be employed sequentially to regulate the rate and duration of laser energy delivery to fuel mixtures, thereby improving fuel ignition performance over a wide range of fuel parameters such as fuel/oxidizer ratios, fuel droplet size, number density and velocity within a fuel aerosol, and initial fuel temperatures.

  15. Multiple laser pulse ignition method and apparatus

    DOE Patents [OSTI]

    Early, J.W.

    1998-05-26

    Two or more laser light pulses with certain differing temporal lengths and peak pulse powers can be employed sequentially to regulate the rate and duration of laser energy delivery to fuel mixtures, thereby improving fuel ignition performance over a wide range of fuel parameters such as fuel/oxidizer ratios, fuel droplet size, number density and velocity within a fuel aerosol, and initial fuel temperatures. 18 figs.

  16. Laser–plasma interactions for fast ignition

    SciTech Connect (OSTI)

    Kemp, A. J.; Fiuza, F.; Debayle, A.; Johzaki, T.; Mori, W. B.; Patel, P. K.; Sentoku, Y.; Silva, L. O.

    2014-04-17

    In the electron-driven fast-ignition approach to inertial confinement fusion, petawatt laser pulses are required to generate MeV electrons that deposit several tens of kilojoules in the compressed core of an imploded DT shell. We review recent progress in the understanding of intense laser- plasma interactions (LPI) relevant to fast ignition. Increases in computational and modeling capabilities, as well as algorithmic developments have led to enhancement in our ability to perform multidimensional particle-in-cell (PIC) simulations of LPI at relevant scales. We discuss the physics of the interaction in terms of laser absorption fraction, the laser-generated electron spectra, divergence, and their temporal evolution. Scaling with irradiation conditions such as laser intensity, f-number and wavelength are considered, as well as the dependence on plasma parameters. Different numerical modeling approaches and configurations are addressed, providing an overview of the modeling capabilities and limitations. In addition, we discuss the comparison of simulation results with experimental observables. In particular, we address the question of surrogacy of today's experiments for the full-scale fast ignition problem.

  17. Laser–plasma interactions for fast ignition

    DOE Public Access Gateway for Energy & Science Beta (PAGES Beta)

    Kemp, A. J.; Fiuza, F.; Debayle, A.; Johzaki, T.; Mori, W. B.; Patel, P. K.; Sentoku, Y.; Silva, L. O.

    2014-04-17

    In the electron-driven fast-ignition approach to inertial confinement fusion, petawatt laser pulses are required to generate MeV electrons that deposit several tens of kilojoules in the compressed core of an imploded DT shell. We review recent progress in the understanding of intense laser- plasma interactions (LPI) relevant to fast ignition. Increases in computational and modeling capabilities, as well as algorithmic developments have led to enhancement in our ability to perform multidimensional particle-in-cell (PIC) simulations of LPI at relevant scales. We discuss the physics of the interaction in terms of laser absorption fraction, the laser-generated electron spectra, divergence, and their temporalmore » evolution. Scaling with irradiation conditions such as laser intensity, f-number and wavelength are considered, as well as the dependence on plasma parameters. Different numerical modeling approaches and configurations are addressed, providing an overview of the modeling capabilities and limitations. In addition, we discuss the comparison of simulation results with experimental observables. In particular, we address the question of surrogacy of today's experiments for the full-scale fast ignition problem.« less

  18. Characterization of in situ oil shale retorts prior to ignition

    DOE Patents [OSTI]

    Turner, Thomas F. (Laramie, WY); Moore, Dennis F. (Laramie, WY)

    1984-01-01

    Method and system for characterizing a vertical modified in situ oil shale retort prior to ignition of the retort. The retort is formed by mining a void at the bottom of a proposed retort in an oil shale deposit. The deposit is then sequentially blasted into the void to form a plurality of layers of rubble. A plurality of units each including a tracer gas cannister are installed at the upper level of each rubble layer prior to blasting to form the next layer. Each of the units includes a receiver that is responsive to a coded electromagnetic (EM) signal to release gas from the associated cannister into the rubble. Coded EM signals are transmitted to the receivers to selectively release gas from the cannisters. The released gas flows through the retort to an outlet line connected to the floor of the retort. The time of arrival of the gas at a detector unit in the outlet line relative to the time of release of gas from the cannisters is monitored. This information enables the retort to be characterized prior to ignition.

  19. Joining of beta-SiC by spark plasma sintering

    SciTech Connect (OSTI)

    Grasso, Salvatore; Tatarko, Peter; Rizzo, S.; Porwal, Harshit; Hu, Chunfeng; Katoh, Yutai; Salvo, M; Reece, Michael John; Ferraris, Monica

    2014-01-01

    Spark plasma sintering (SPS) was employed to join monolithic -SiC with or without titanium as intermediate joining material. Both the localizedand rapid heating contributed to the inherent energy saving of electric current assisted joining technique. The effects of uniaxial pressure and surfacepreparation were analyzed independently with respect to the flexural strength and the morphology of the joints. In particular samples polisheddown to 1 m and joined at 1900 C for 5 min achieved the strength of the as received material. The failure occurred outside the joining interface,confirming the optimum quality of the joint. Pressure in combination with surface preparation was necessary to achieve perfect adhesion and porefree direct joining of SiC. The use of Ti foil as a joining material and pressure allowed joining of unpolished SiC.

  20. The Absence of Plasma in"Spark Plasma Sintering"

    SciTech Connect (OSTI)

    Hulbert, Dustin M.; Anders, Andre; Dudina, Dina V.; Andersson, Joakim; Jiang, Dongtao; Unuvar, Cosan; Anselmi-Tamburini, Umberto; Lavernia, Enrique J.; Mukherjee, Amiya K.

    2008-04-10

    Spark plasma sintering (SPS) is a remarkable method for synthesizing and consolidating a large variety of both novel and traditional materials. The process typically uses moderate uni-axial pressures (<100 MPa) in conjunction with a pulsing on-off DC current during operation. There are a number of mechanisms proposed to account for the enhanced sintering abilities of the SPS process. Of these mechanisms, the one most commonly put forth and the one that draws the most controversy involves the presence of momentary plasma generated between particles. This study employees three separate experimental methods in an attempt to determine the presence or absence of plasma during SPS. The methods employed include: in-situ atomic emission spectroscopy, direct visual observation and ultra-fast in-situ voltage measurements. It was found using these experimental techniques that no plasma is present during the SPS process. This result was confirmed using several different powders across a wide spectrum of SPS conditions.

  1. Multi-zone modelling of partially premixed low-temperature combustion in pilot-ignited natural-gas engines

    SciTech Connect (OSTI)

    Krishnan, S. R.; Srinivasan, K. K.

    2010-06-29

    Detailed results from a multi-zone phenomenological simulation of partially premixed advanced-injection low-pilot-ignited natural-gas low-temperature combustion are presented with a focus on early injection timings (the beginning of (pilot) injection (BOI)) and very small diesel quantities (2-3 per cent of total fuel energy). Combining several aspects of diesel and spark ignition engine combustion models, the closed-cycle simulation accounted for diesel autoignition, diesel spray combustion, and natural-gas combustion by premixed turbulent flame propagation. The cylinder contents were divided into an unburned zone, several pilot fuel zones (or 'packets') that modelled diesel evaporation and ignition, a flame zone for natural-gas combustion, and a burned zone. The simulation predicted the onset of ignition, cylinder pressures, and heat release rate profiles satisfactorily over a wide range of BOIs (20-60???° before top dead centre (before TDC)) but especially well at early BOIs. Strong coupling was observed between pilot spray combustion in the packets and premixed turbulent combustion in the flame zone and, therefore, the number of ignition centres (packets) profoundly affected flame combustion. The highest local peak temperatures (greater than 2000 K) were observed in the packets, while the flame zone was much cooler (about 1650 K), indicating that pilot diesel spray combustion is probably the dominant source of engine-out emissions of nitrogen oxide (NO x). Further, the 60???° before TDC BOI yielded the lowest average peak packet temperatures (about 1720 K) compared with the 20???° before TDC BOI (about 2480 K) and 40???° before TDC BOI (about 2700 K). These trends support experimental NO x trends, which showed the lowest NO x emissions for the 60???°, 20???°, and 40???° before TDC BOIs in that order. Parametric studies showed that increasing the intake charge temperature, pilot quantity, and natural-gas equivalence ratio all led to higher peak heat release rates and hotter packets but the pilot quantity and intake temperature affected the potential for NO x formation to a greater extent.

  2. National Ignition Facility & Photon Science Seven WonderS

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    1 National Ignition Facility & Photon Science Seven WonderS the seven wonders of niF While construction of the football-stadium- sized National Ignition Facility was a marvel of engineering, NIF is also a tour de force of science and technology development. To complete NIF construction and comissioning and to put NIF on the path to ignition experiments, scientists, engineers, and technicians had to overcome a daunting array of challenges. Working closely with industrial partners, the NIF

  3. Modeling the Number of Ignitions Following an Earthquake: Developing

    Office of Environmental Management (EM)

    Prediction Limits for Overdispersed Count Data | Department of Energy the Number of Ignitions Following an Earthquake: Developing Prediction Limits for Overdispersed Count Data Modeling the Number of Ignitions Following an Earthquake: Developing Prediction Limits for Overdispersed Count Data Modeling the Number of Ignitions Following an Earthquake: Developing Prediction Limits for Overdispersed Count Data Authors: Elizabeth J. Kelly and Raymond N. Tell PDF icon Modeling the Number of

  4. High Efficiency Fuel Reactivity Controlled Compression Ignition Combustion

    Office of Energy Efficiency and Renewable Energy (EERE) Indexed Site

    | Department of Energy Fuel Reactivity Controlled Compression Ignition Combustion High Efficiency Fuel Reactivity Controlled Compression Ignition Combustion An optimized dual-fuel PCCI concept, RCCI, is proposed. PDF icon deer10_reitz.pdf More Documents & Publications Effect of Compression Ratio and Piston Geometry on RCCI load limit Optimization of Advanced Diesel Engine Combustion Strategies Comparison of Conventional Diesel and Reactivity Controlled Compression Ignition (RCCI)

  5. High Fidelity Modeling of Premixed Charge Compression Ignition Engines |

    Office of Energy Efficiency and Renewable Energy (EERE) Indexed Site

    Department of Energy Fidelity Modeling of Premixed Charge Compression Ignition Engines High Fidelity Modeling of Premixed Charge Compression Ignition Engines Most accurate and detailed chemical kinetic models for fuels of practical interest to engine manufacturers and fuels developers are applied for high fidelity engine analysis of premixed charge compression ignition engines. PDF icon deer08_aceves.pdf More Documents & Publications Numerical Modeling of HCCI Combustion Modeling of high

  6. Effects of Ignition Quality and Fuel Composition on Critical Equivalence

    Office of Energy Efficiency and Renewable Energy (EERE) Indexed Site

    Ratio | Department of Energy Effects of Ignition Quality and Fuel Composition on Critical Equivalence Ratio Effects of Ignition Quality and Fuel Composition on Critical Equivalence Ratio Our research shows that fuel can be blended to have a low ignition quality, which is desirable for high-efficiency advanced combustion, and with a high n-paraffin content to reduce CO and THC. PDF icon deer12_lilik.pdf More Documents & Publications Vehicle Technologies Office Merit Review 2014: Fuel

  7. Stoichiometric Compression Ignition (SCI) Engine Concept | Department of

    Office of Energy Efficiency and Renewable Energy (EERE) Indexed Site

    Energy Stoichiometric Compression Ignition (SCI) Engine Concept Stoichiometric Compression Ignition (SCI) Engine Concept Presentation given at DEER 2006, August 20-24, 2006, Detroit, Michigan. Sponsored by the U.S. DOE's EERE FreedomCar and Fuel Partnership and 21st Century Truck Programs. PDF icon 2006_deer_winsor.pdf More Documents & Publications An Experimental Investigation of the Origin of Increased NOx Emissions When Fueling a Heavy-Duty Compression-Ignition Engine with Soy

  8. Optical key system

    DOE Patents [OSTI]

    Hagans, Karla G. (Livermore, CA); Clough, Robert E. (Danville, CA)

    2000-01-01

    An optical key system comprises a battery-operated optical key and an isolated lock that derives both its operating power and unlock signals from the correct optical key. A light emitting diode or laser diode is included within the optical key and is connected to transmit a bit-serial password. The key user physically enters either the code-to-transmit directly, or an index to a pseudorandom number code, in the key. Such person identification numbers can be retained permanently, or ephemeral. When a send button is pressed, the key transmits a beam of light modulated with the password information. The modulated beam of light is received by a corresponding optical lock with a photovoltaic cell that produces enough power from the beam of light to operate a password-screen digital logic. In one application, an acceptable password allows a two watt power laser diode to pump ignition and timing information over a fiberoptic cable into a sealed engine compartment. The receipt of a good password allows the fuel pump, spark, and starter systems to each operate. Therefore, bypassing the lock mechanism as is now routine with automobile thieves is pointless because the engine is so thoroughly disabled.

  9. Electron Generation and Transport in Intense Relativistic Laser-Plasma Interactions Relevant to Fast Ignition ICF

    SciTech Connect (OSTI)

    Ma, T

    2010-04-21

    The reentrant cone approach to Fast Ignition, an advanced Inertial Confinement Fusion scheme, remains one of the most attractive because of the potential to efficiently collect and guide the laser light into the cone tip and direct energetic electrons into the high density core of the fuel. However, in the presence of a preformed plasma, the laser energy is largely absorbed before it can reach the cone tip. Full scale fast ignition laser systems are envisioned to have prepulses ranging between 100 mJ to 1 J. A few of the imperative issues facing fast ignition, then, are the conversion efficiency with which the laser light is converted to hot electrons, the subsequent transport characteristics of those electrons, and requirements for maximum allowable prepulse this may put on the laser system. This dissertation examines the laser-to-fast electron conversion efficiency scaling with prepulse for cone-guided fast ignition. Work in developing an extreme ultraviolet imager diagnostic for the temperature measurements of electron-heated targets, as well as the validation of the use of a thin wire for simultaneous determination of electron number density and electron temperature will be discussed.

  10. NREL Ignites New Renewable Fuels Heating Plant - News Releases...

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Golden, Colo. - With the spark from a high intensity road flare, engineers at the U.S. Department of Energy's National Renewable Energy Laboratory lit its new, smoke-free Renewable ...

  11. Modeling the Number of Ignitions Following an Earthquake: Developing...

    Office of Environmental Management (EM)

    Developing Prediction Limits for Overdispersed Count Data Authors: Elizabeth J. Kelly and Raymond N. Tell PDF icon Modeling the Number of Ignitions Following an Earthquake:...

  12. Ultrafast Laser Diagnostics for Energetic-Material Ignition Mechanisms...

    Office of Scientific and Technical Information (OSTI)

    Technical Report: Ultrafast Laser Diagnostics for Energetic-Material Ignition Mechanisms: Tools for Physics-Based Model Development. Citation Details In-Document Search Title: ...

  13. Radiochemical tracers as a mix diagnostic for the ignition double...

    Office of Scientific and Technical Information (OSTI)

    for the ignition double-shell capsule One of the most important challenges confronting laser-driven capsule implosion experiments will be a quantitative evaluation of the...

  14. Effects of Ignition Quality and Fuel Composition on Critical...

    Office of Energy Efficiency and Renewable Energy (EERE) Indexed Site

    in Fuel Spray and Combustion Modeling for Compression Ignition Engine Applications A University Consortium on Efficient and Clean High-Pressure, Lean Burn (HPLB) Engines

  15. Cosmos Ignite Innovations Pvt Ltd | Open Energy Information

    Open Energy Info (EERE)

    Innovations Pvt Ltd Jump to: navigation, search Name: Cosmos Ignite Innovations Pvt Ltd Place: Delhi (NCT), India Zip: 110017 Product: Company started by two Stanford and New Delhi...

  16. Modeling the Fuel Spray and Combustion Process of the Ignition Quality Tester with KIVA-3V

    SciTech Connect (OSTI)

    Bogin, G. E. Jr.; DeFilippo, A.; Chen, J. Y.; Chin, G.; Luecke, J.; Ratcliff, M. A.; Zigler, B. T.; Dean, A. M.

    2010-05-01

    Discusses the use of KIVA-3V to develop a model that reproduces ignition behavior inside the Ignition Quality Tester, which measures the ignition delay of low-volatility fuels.

  17. Low emissions compression ignited engine technology

    DOE Patents [OSTI]

    Coleman, Gerald N. (Dunlap, IL); Kilkenny, Jonathan P. (Peoria, IL); Fluga, Eric C. (Dunlap, IL); Duffy, Kevin P. (East Peoria, IL)

    2007-04-03

    A method and apparatus for operating a compression ignition engine having a cylinder wall, a piston, and a head defining a combustion chamber. The method and apparatus includes delivering fuel substantially uniformly into the combustion chamber, the fuel being dispersed throughout the combustion chamber and spaced from the cylinder wall, delivering an oxidant into the combustion chamber sufficient to support combustion at a first predetermined combustion duration, and delivering a diluent into the combustion chamber sufficient to change the first predetermined combustion duration to a second predetermined combustion duration different from the first predetermined combustion duration.

  18. National Ignition Facility & Photon Science

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    1 National Ignition Facility & Photon Science limitless energy the Promise of Limitless energy harnessing the energy of the sun and stars to meet the earth's energy needs has been a decades-long scientific and engineering quest. While a self-sustaining fusion burn has been achieved for brief periods under experimental conditions, the amount of energy that went into creating it was greater than the amount of energy it generated. There was no energy gain, which is essential if fusion energy is

  19. National Ignition Facility & Photon Science

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    making a star 17 How to make a miniature star The idea for the National Ignition Facility (NIF) grew out of a decades-long effort to generate fusion burn and energy gain in the laboratory. Current nuclear power plants, which use the splitting of atoms (fission) to produce energy, have been pumping out electric power for more than 50 years. But achieving nuclear fusion burn and gain has not yet been demonstrated as viable for energy production. For fusion burn and gain to occur, a special fuel

  20. Validating hydrodynamic growth in National Ignition Facility implosions

    SciTech Connect (OSTI)

    Peterson, J. L. Casey, D. T.; Hurricane, O. A.; Raman, K. S.; Robey, H. F.; Smalyuk, V. A.

    2015-05-15

    We present new hydrodynamic growth experiments at the National Ignition Facility, which extend previous measurements up to Legendre mode 160 and convergence ratio 4, continuing the growth factor dispersion curve comparison of the low foot and high foot pulses reported by Casey et al. [Phys. Rev. E 90, 011102(R) (2014)]. We show that the high foot pulse has lower growth factor and lower growth rate than the low foot pulse. Using novel on-capsule fiducial markers, we observe that mode 160 inverts sign (changes phase) for the high foot pulse, evidence of amplitude oscillations during the Richtmyer-Meshkov phase of a spherically convergent system. Post-shot simulations are consistent with the experimental measurements for all but the shortest wavelength perturbations, reinforcing the validity of radiation hydrodynamic simulations of ablation front growth in inertial confinement fusion capsules.

  1. Bent paths of a positive streamer and a cathode-directed spark...

    Office of Scientific and Technical Information (OSTI)

    In our opinion, such propagation of the positive streamer and the cathode-directed spark leader at some angle to the background electric field lines owes to different increase ...

  2. Apparatus and method for the spectrochemical analysis of liquids using the laser spark

    DOE Patents [OSTI]

    Cremers, David A. (Los Alamos, NM); Radziemski, Leon J. (Las Cruces, NM); Loree, Thomas R. (Los Alamos, NM)

    1990-01-01

    A method and apparatus for the qualitative and quantitative spectroscopic investigation of elements present in a liquid sample using the laser spark. A series of temporally closely spaced spark pairs is induced in the liquid sample utilizing pulsed electromagnetic radiation from a pair of lasers. The light pulses are not significantly absorbed by the sample so that the sparks occur inside of the liquid. The emitted light from the breakdown events is spectrally and temporally resolved, and the time period between the two laser pulses in each spark pair is adjusted to maximize the signal-to-noise ratio of the emitted signals. In comparison with the single pulse technique, a substantial reduction in the limits of detectability for many elements has been demonstrated. Narrowing of spectral features results in improved discrimination against interfering species.

  3. Apparatus and method for the spectrochemical analysis of liquids using the laser spark

    DOE Patents [OSTI]

    Cremers, D.A.; Radziemski, L.J.; Loree, T.R.

    1984-05-01

    A method and apparatus are disclosed for the qualitative and quantitative spectroscopic investigation of elements present in a liquid sample using the laser spark. A series of temporally closely spaced spark pairs is induced in the liquid sample utilizing pulsed electromagnetic radiation from a pair of lasers. The light pulses are not significantly absorbed by the sample so that the sparks occur inside of the liquid. The emitted light from the breakdown events is spectrally and temporally resolved, and the time period between the two laser pulses in each spark pair is adjusted to maximize the signal-to-noise ratio of the emitted signals. In comparison with the single pulse technique, a substantial reduction in the limits of detectability for many elements has been demonstrated. Narrowing of spectral features results in improved discrimination against interfering species.

  4. SULI Intern: Gasoline Compression Ignition | Argonne National Laboratory

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Gasoline Compression Ignition Share Argonne intern Kendyl Partridge from Mississippi State University worked with Argonne mentor Steve Ciatti in studying gasoline compression ignition engines. This research will help engineers increase an engine's efficiency while reducing its environmental impact. Browse By - Any - Energy -Energy efficiency --Vehicles ---Alternative fuels ---Automotive engineering ---Diesel ---Electric drive technology ---Hybrid & electric vehicles ---Hydrogen & fuel

  5. Observing the Sparks of Life | U.S. DOE Office of Science (SC)

    Office of Science (SC) Website

    Observing the Sparks of Life Energy Frontier Research Centers (EFRCs) EFRCs Home Centers Research Science Highlights News & Events EFRC News EFRC Events DOE Announcements Publications History Contact BES Home 12.30.13 Observing the Sparks of Life Print Text Size: A A A Subscribe FeedbackShare Page EFRC researchers isolate a photosynthetic complex - arguably the most important bit of organic chemistry on the planet - in its complete functioning state. This work, featured in the Office of

  6. Enabling and Expanding HCCI in PFI Gasoline Engines with High EGR and Spark

    Office of Energy Efficiency and Renewable Energy (EERE) Indexed Site

    Assist | Department of Energy and Expanding HCCI in PFI Gasoline Engines with High EGR and Spark Assist Enabling and Expanding HCCI in PFI Gasoline Engines with High EGR and Spark Assist 2005 Diesel Engine Emissions Reduction (DEER) Conference Presentations and Posters PDF icon 2005_deer_wagner.pdf More Documents & Publications Vehicle Technologies Office Merit Review 2015: High-Dilution Stoichiometric Gasoline Direct-Injection (SGDI) Combustion Control Development Enabling the Next

  7. National Ignition Facility project acquisition plan

    SciTech Connect (OSTI)

    Callaghan, R.W.

    1996-04-01

    The purpose of this National Ignition Facility Acquisition Plan is to describe the overall procurement strategy planned for the National Ignition Facility (NIF) Project. The scope of the plan describes the procurement activities and acquisition strategy for the following phases of the NIF Project, each of which receives either plant and capital equipment (PACE) or other project cost (OPC) funds: Title 1 and 2 design and Title 3 engineering (PACE); Optics manufacturing facilitization and pilot production (OPC); Convention facility construction (PACE); Procurement, installation, and acceptance testing of equipment (PACE); and Start-up (OPC). Activities that are part of the base Inertial Confinement Fusion (ICF) Program are not included in this plan. The University of California (UC), operating Lawrence Livermore National Laboratory (LLNL) and Los Alamos National Laboratory, and Lockheed-Martin, which operates Sandia National Laboratory (SNL) and the University of Rochester Laboratory for Laser Energetics (UR-LLE), will conduct the acquisition of needed products and services in support of their assigned responsibilities within the NIF Project structure in accordance with their prime contracts with the Department of Energy (DOE). LLNL, designated as the lead Laboratory, will have responsibility for all procurements required for construction, installation, activation, and startup of the NIF.

  8. PBXN-9 Ignition Kinetics and Deflagration Rates

    SciTech Connect (OSTI)

    Glascoe, E; Maienschein, J; Burnham, A; Koerner, J; Hsu, P; Wemhoff, A

    2008-04-24

    The ignition kinetics and deflagration rates of PBXN-9 were measured using specially designed instruments at LLNL and compared with previous work on similar HMX based materials. Ignition kinetics were measured based on the One Dimensional Time-to-Explosion combined with ALE3D modeling. Results of these experiments indicate that PBXN-9 behaves much like other HMX based materials (i.e. LX-04, LX-07, LX-10 and PBX-9501) and the dominant factor in these experiments is the type of explosive, not the type of binder/plasticizer. In contrast, the deflagration behavior of PBXN-9 is quite different from similar high weight percent HMX based materials (i.e LX-10, LX-07 and PBX-9501). PBXN-9 burns in a laminar manner over the full pressure range studied (0-310 MPa) unlike LX-10, LX-07, and PBX-9501. The difference in deflagration behavior is attributed to the nature of the binder/plasticizer alone or in conjunction with the volume of binder present in PBXN-9.

  9. SCB ignition of pyrotechnics, thermites and intermetallics

    SciTech Connect (OSTI)

    Bickes, R.W. Jr.; Grubelich, M.C.

    1996-09-01

    We investigated ignition of pyrotechnics, metal-fuel/metal-oxide compositions (thermites), and exothermic alloy compositions (intermetallics) using a semiconductor bridge (SCB). It was shown that these materials could be ignited at low energy levels with an appropriately designed SCB, proper loading density, and good thermal isolation. Materials tested included Al/CuO, B/BaCrO{sub 4}, TiH{sub 1.65}/KClO{sub 4}, Ti/KClO{sub 4}, Zr/BaCrO{sub 4}, Zr/CuO, Zr/Fe{sub 2}O{sub 3}, Zr/KClO{sub 4}, and 100-mesh Al/Pd. Firing set was a capacitor discharge unit with charge capacitors ranging from 3 to 20,000 {mu}F at charge voltages 5-50 V. Devices functioned a few miliseconds after onset of current pulse at input energies as low as 3 mJ. We also report on a thermite torch design.

  10. Quantifying the Effects of Idle-Stop Systems on Fuel Economy in Light-Duty Passenger Vehicles

    SciTech Connect (OSTI)

    Jeff Wishart; Matthew Shirk

    2012-12-01

    Vehicles equipped with idle-stop (IS) systems are capable of engine shut down when the vehicle is stopped and rapid engine re-start for the vehicle launch. This capability reduces fuel consumption and emissions during periods when the engine is not being utilized to provide propulsion or to power accessories. IS systems are a low-cost and fast-growing technology in the industry-wide pursuit of increased vehicle efficiency, possibly becoming standard features in European vehicles in the near future. In contrast, currently there are only three non-hybrid vehicle models for sale in North America with IS systems and these models are distinctly low-volume models. As part of the United States Department of Energys Advanced Vehicle Testing Activity, ECOtality North America has tested the real-world effect of IS systems on fuel consumption in three vehicle models imported from Europe. These vehicles were chosen to represent three types of systems: (1) spark ignition with 12-V belt alternator starter; (2) compression ignition with 12-V belt alternator starter; and (3) direct-injection spark ignition, with 12-V belt alternator starter/combustion restart. The vehicles have undergone both dynamometer and on-road testing; the test results show somewhat conflicting data. The laboratory data and the portion of the on-road data in which driving is conducted on a prescribed route with trained drivers produced significant fuel economy improvement. However, the fleet data do not corroborate improvement, even though the data show significant engine-off time. It is possible that the effects of the varying driving styles and routes in the fleet testing overshadowed the fuel economy improvements. More testing with the same driver over routes that are similar with the IS system-enabled and disabled is recommended. There is anecdotal evidence that current Environmental Protection Agency fuel economy test procedures do not capture the fuel economy gains that IS systems produce in real-world driving. The program test results provide information on the veracity of these claims.

  11. Variable valve timing in a homogenous charge compression ignition engine

    DOE Patents [OSTI]

    Lawrence, Keith E.; Faletti, James J.; Funke, Steven J.; Maloney, Ronald P.

    2004-08-03

    The present invention relates generally to the field of homogenous charge compression ignition engines, in which fuel is injected when the cylinder piston is relatively close to the bottom dead center position for its compression stroke. The fuel mixes with air in the cylinder during the compression stroke to create a relatively lean homogeneous mixture that preferably ignites when the piston is relatively close to the top dead center position. However, if the ignition event occurs either earlier or later than desired, lowered performance, engine misfire, or even engine damage, can result. The present invention utilizes internal exhaust gas recirculation and/or compression ratio control to control the timing of ignition events and combustion duration in homogeneous charge compression ignition engines. Thus, at least one electro-hydraulic assist actuator is provided that is capable of mechanically engaging at least one cam actuated intake and/or exhaust valve.

  12. Ignition of ethane, propane, and butane in counterflow jets of cold fuel versus hot air under variable pressures

    SciTech Connect (OSTI)

    Fotache, C.G.; Wang, H.; Law, C.K.

    1999-06-01

    This study investigates experimentally the nonpremixed ignition of ethane, propane, n-butane, and isobutane in a configuration of opposed fuel versus heated air jets. For each of these fuels the authors explore the effects of inert dilution, system pressure, and flow strain rate, for fuel concentrations ranging between 3--100% by volume, pressures between 0.2 and 8 atm, and strain rates of 100--600 s{sup {minus}1}. Qualitatively, these fuels share a number of characteristics. First, flame ignition typically occurs after an interval of mild oxidation, characterized by minimal heat release, fuel conversion, and weak light emission. The temperature extent of this regime decreases with increasing the fuel concentration, the ambient pressure, or the flow residence time. Second, the response to strain rate, pressure, and fuel concentration is similar for all investigated fuels, in that the ignition temperatures monotonically decrease with increasing fuel content, decreasing flow strain, and increasing ambient pressure. The C{sub 4} alkanes, however, exhibit three distinct p-T ignition regimes, similar to the homogeneous explosion limits. Finally, at 1 atm, 100% fuel, and a fixed flow strain rate the ignition temperature increases in the order of ethane < propane < n-butane < i-butane. Numerical simulation was conducted for ethane ignition using detailed reaction kinetics and transport descriptions. The modeling results suggest that ignition for all fuels studied at pressures below 5 atm is initiated by fuel oxidation following the high-temperature mechanism of radical chain branching and with little contribution by low-to-intermediate temperature chemistry.

  13. Gas flow stabilized megavolt spark gap for repetitive pulses

    DOE Patents [OSTI]

    Lawson, Robert N. (Albuquerque, NM); O'Malley, Martin W. (Albuquerque, NM); Rohwein, Gerald J. (Albuquerque, NM)

    1986-01-01

    A high voltage spark gap switch including a housing having first and second end walls being spaced apart by a predetermined distance. A first electrode is positioned on the first end wall and a second electrode is positioned on the second end wall. The first and second electrodes are operatively disposed relative to each other and are spaced apart by a predetermined gap. An inlet conduit is provided for supplying gas to the first electrode. The conduit includes a nozzle for dispersing the gas in the shape of an annular jet. The gas is supplied into the housing at a predetermined velocity. A venturi housing is disposed within the second electrode. An exhaust conduit is provided for discharging gas and residue from the housing. The gas supplied at the predetermined velocity to the housing through the inlet conduit and the nozzle in an annular shape traverses the gap between the first and second electrodes and entrains low velocity gas within the housing decreasing the velocity of the gas supplied to the housing and increasing the diameter of the annular shape. The venturi disposed within the second electrode recirculates a large volume of gas to clean and cool the surface of the electrodes.

  14. Catalytic igniters and their use to ignite lean hydrogen-air mixtures

    DOE Patents [OSTI]

    McLean, William J. (Oakland, CA); Thorne, Lawrence R. (Livermore, CA); Volponi, Joanne V. (Livermore, CA)

    1988-01-01

    A catalytic igniter which can ignite a hydrogen-air mixture as lean as 5.5% hydrogen with induction times ranging from 20 s to 400 s, under conditions which may be present during a loss-of-liquid-coolant accident at a light water nuclear reactor comprises (a) a perforate catalytically active substrate, such as a platinum coated ceramic honeycomb or wire mesh screen, through which heated gases produced by oxidation of the mixture can freely flow and (b) a plurality of thin platinum wires mounted in a thermally conductive manner on the substrate and positioned thereon so as to be able to receive heat from the substrate and the heated gases while also in contact with unoxidized gases.

  15. Future prospects for compression ignition fuel in California : fuel-related implications of possible pathways to mitigation of public health threats.

    SciTech Connect (OSTI)

    Eberhardt, J. J.; Rote, D. M.; Saricks, C. L.; Stodolsky, F.

    1999-04-08

    This paper documents methods and results of an investigation of the options for and year 2010 consequences of possible new limitations on the use of diesel fuel in California, USA. California's Air Resources Board will undertake a risk management process to determine steps necessary to protect the health and safety of the public from carcinogenic species resident on diesel combustion exhaust particles. Environmental activist groups continue to call for the elimination of diesel fuel in California and other populous states. It is the declared intention of CARB not to ban or restrict diesel fuel, per se, at this time. Thus, two ''mid-course'' strategies now appear feasible: (1) Increased penetration of natural gas, LPG, and possibly lower alcohols into the transportation fuels market, to the extent that some Cl applications would revert to spark-ignition (SI) engines. (2) New specifications requiring diesel fuel reformulation based on more detailed investigation of exhaust products of individual diesel fuel constituents.

  16. Pre-ignition laser ablation of nanocomposite energetic materials

    SciTech Connect (OSTI)

    Stacy, S. C.; Massad, R. A.; Pantoya, M. L.

    2013-06-07

    Laser ignition of energetic material composites was studied for initiation with heating rates from 9.5 Multiplication-Sign 10{sup 4} to 1.7 Multiplication-Sign 10{sup 7} K/s. This is a unique heating rate regime for laser ignition studies because most studies employ either continuous wave CO{sub 2} lasers to provide thermal ignition or pulsed Nd:YAG lasers to provide shock ignition. In this study, aluminum (Al) and molybdenum trioxide (MoO{sub 3}) nanoparticle powders were pressed into consolidated pellets and ignited using a Nd:YAG laser (1064 nm wavelength) with varied pulse energy. Results show reduced ignition delay times corresponding to laser powers at the ablation threshold for the sample. Heating rate and absorption coefficient were determined from an axisymmetric heat transfer model. The model estimates absorption coefficients from 0.1 to 0.15 for consolidated pellets of Al + MoO{sub 3} at 1064 nm wavelength. Ablation resulted from fracturing caused by a rapid increase in thermal stress and slowed ignition of the pellet.

  17. Hydrogen-assisted catalytic ignition characteristics of different fuels

    SciTech Connect (OSTI)

    Zhong, Bei-Jing; Yang, Fan; Yang, Qing-Tao

    2010-10-15

    Hydrogen-assisted catalytic ignition characteristics of methane (CH{sub 4}), n-butane (n-C{sub 4}H{sub 10}) and dimethyl ether (DME) were studied experimentally in a Pt-coated monolith catalytic reactor. It is concluded that DME has the lowest catalytic ignition temperature and the least required H{sub 2} flow, while CH{sub 4} has the highest catalytic ignition temperature and the highest required H{sub 2} flow among the three fuels. (author)

  18. Fuel reactivity effects on the efficiency and operational window of dual-fuel compression ignition engines

    SciTech Connect (OSTI)

    Splitter, Derek A; Reitz, Rolf

    2014-01-01

    Fuel reactivity effects on the efficiency and operational window of dual-fuel compression ignition engines

  19. Simulations of Inertial Confinement Fusion Driven by a Novel Synchrotron Radiation-Based X-Ray Igniter

    SciTech Connect (OSTI)

    Shlyaptsev, V; Tatchyn, R

    2004-01-13

    The advantages and challenges of using a powerful x-ray source for the fast ignition of compressed Inertial Confinement Fusion (ICF) targets have been considered. The requirements for such a source together with the optics to focus the x-rays onto compressed DT cores lead to a conceptual design based on Energy Recovery Linacs (ERLs) and long wigglers to produce x-ray pulses with the appropriate phase space properties. A comparative assessment of the parameters of the igniter system indicates that the technologies for building it, although expensive, are physically achievable. Our x-ray fast ignition (XFI) scheme requires substantially smaller energy for the initiation of nuclear fusion reactions than other methods.

  20. Modeling the Number of Ignitions Following an Earthquake: Developing...

    Office of Environmental Management (EM)

    the likelihood of various fire scenarios. The first component of the approach is a statistical model to predict the number of ignitions for a new earthquake event. This model is...

  1. The National Ignition Facility (NIF) - September 23, 2010 | Department...

    Broader source: Energy.gov (indexed) [DOE]

    NIF03.23.10(1).pdf More Documents & Publications The National Ignition Facility (NIF) - September 23, 2010 EIS-0236-S1: Supplemental Environmental Impact Statement EIS-0236-S1:...

  2. The National Ignition Facility (NIF) - September 23, 2010 | Department...

    Broader source: Energy.gov (indexed) [DOE]

    NIF03.23.10.pdf More Documents & Publications The National Ignition Facility (NIF) - September 23, 2010 EIS-0236-S1: Supplemental Environmental Impact Statement EIS-0236-S1:...

  3. Compact Ignition Tokamak Program: status of FEDC studies

    SciTech Connect (OSTI)

    Flanagan, C.A.

    1985-01-01

    Viewgraphs on the Compact Ignition Tokamak Program comprise the report. The technical areas discussed are the mechanical configuration status, magnet analysis, stress analysis, cooling between burns, TF coil joint, and facility/device layout options. (WRF)

  4. Gasoline Compression Ignition - Start of Injection Timing Sweep...

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Contact Us For more information, contact Greg Cunningham at (630) 252-8232 or media@anl.gov. Gasoline Compression Ignition - Start of Injection Timing Sweep (VERIFI) Share Topic...

  5. Ignition technique for an in situ oil shale retort

    DOE Patents [OSTI]

    Cha, Chang Y. (Golden, CO)

    1983-01-01

    A generally flat combustion zone is formed across the entire horizontal cross-section of a fragmented permeable mass of formation particles formed in an in situ oil shale retort. The flat combustion zone is formed by either sequentially igniting regions of the surface of the fragmented permeable mass at successively lower elevations or by igniting the entire surface of the fragmented permeable mass and controlling the rate of advance of various portions of the combustion zone.

  6. High-Efficiency Clean Combustion Design for Compression Ignition Engines |

    Office of Energy Efficiency and Renewable Energy (EERE) Indexed Site

    Department of Energy High-Efficiency Clean Combustion Design for Compression Ignition Engines High-Efficiency Clean Combustion Design for Compression Ignition Engines Presentation given at DEER 2006, August 20-24, 2006, Detroit, Michigan. Sponsored by the U.S. DOE's EERE FreedomCar and Fuel Partnership and 21st Century Truck Programs. PDF icon 2006_deer_potter.pdf More Documents & Publications Visualization of UHC Emissions for Low-Temperature Diesel Engine Combustion Sources and

  7. Hydrocarbon fouling of SCR during Premixed Charge Compression Ignition

    Office of Energy Efficiency and Renewable Energy (EERE) Indexed Site

    (PCCI) combustion | Department of Energy fouling of SCR during Premixed Charge Compression Ignition (PCCI) combustion Hydrocarbon fouling of SCR during Premixed Charge Compression Ignition (PCCI) combustion Analyzed the effects of higher hydrocarbon emissions from PCCI combustion on SCR catalysts in operating a light-duty 1.9-liter GM diesel engine in both PCCI and conventional combustion modes PDF icon deer11_parks.pdf More Documents & Publications Efficient Emissions Control for

  8. Ultrafast Laser Diagnostics for Energetic-Material Ignition Mechanisms:

    Office of Scientific and Technical Information (OSTI)

    Tools for Physics-Based Model Development. (Technical Report) | SciTech Connect Ultrafast Laser Diagnostics for Energetic-Material Ignition Mechanisms: Tools for Physics-Based Model Development. Citation Details In-Document Search Title: Ultrafast Laser Diagnostics for Energetic-Material Ignition Mechanisms: Tools for Physics-Based Model Development. We present the results of an LDRD project to develop diagnostics to perform fundamental measurements of material properties during shock

  9. Energetics Measurements of Silver Halfraum Targets at the National Ignition

    Office of Scientific and Technical Information (OSTI)

    Facility (Journal Article) | SciTech Connect Journal Article: Energetics Measurements of Silver Halfraum Targets at the National Ignition Facility Citation Details In-Document Search Title: Energetics Measurements of Silver Halfraum Targets at the National Ignition Facility Authors: May, M J ; Fournier, K B ; Brown, C G ; Dunlop, W H ; Kane, J O ; Mirkarimi, P B ; Moody, J ; Patterson, R ; Schneider, M ; Widmann, K Publication Date: 2013-09-09 OSTI Identifier: 1229821 Report Number(s):

  10. Ultrafast Laser Diagnostics for Energetic-Material Ignition Mechanisms:

    Office of Scientific and Technical Information (OSTI)

    Tools for Physics-Based Model Development. (Technical Report) | SciTech Connect Technical Report: Ultrafast Laser Diagnostics for Energetic-Material Ignition Mechanisms: Tools for Physics-Based Model Development. Citation Details In-Document Search Title: Ultrafast Laser Diagnostics for Energetic-Material Ignition Mechanisms: Tools for Physics-Based Model Development. × You are accessing a document from the Department of Energy's (DOE) SciTech Connect. This site is a product of DOE's Office

  11. Heating National Ignition Facility, Realistic Financial Planning & Rapid

    Broader source: Energy.gov (indexed) [DOE]

    Modification Lessons Learned Report Apr 2010 | Department of Energy 628 National Ignition Facility Realistic Financial Planning Rapid Modification are Essential Lessons Learned Report Apr 2010.pdf More Documents & Publications EIS-0236-S1: Record of Decision EIS-0236-S1: Supplemental Environmental Impact Statement DOE/EIS-0236, Oakland Operations Office, National Ignition Facility Final Supplemental Environmental Impact Statement to the Stockpile Stewardship and Management Programmatic

  12. Characterization of Dual-Fuel Reactivity Controlled Compression Ignition

    Office of Energy Efficiency and Renewable Energy (EERE) Indexed Site

    (RCCI) Using Hydrated Ethanol and Diesel Fuel | Department of Energy Dual-Fuel Reactivity Controlled Compression Ignition (RCCI) Using Hydrated Ethanol and Diesel Fuel Characterization of Dual-Fuel Reactivity Controlled Compression Ignition (RCCI) Using Hydrated Ethanol and Diesel Fuel This study uses numerical simulations to explore the use of wet ethanol as the low-reactivity fuel and diesel as the high-reactivity fuel for RCCI operation in a heavy-duty diesel engine. PDF icon

  13. Efficiency Considerations of Diesel Premixed Charge Compression Ignition

    Office of Energy Efficiency and Renewable Energy (EERE) Indexed Site

    Combustion | Department of Energy Efficiency Considerations of Diesel Premixed Charge Compression Ignition Combustion Efficiency Considerations of Diesel Premixed Charge Compression Ignition Combustion Poster presented at the 16th Directions in Engine-Efficiency and Emissions Research (DEER) Conference in Detroit, MI, September 27-30, 2010. PDF icon p-06_jacobs.pdf More Documents & Publications Biodiesel's Enabling Characteristics in Attaining Low Temperature Diesel Combustion

  14. Ultrafast Laser Diagnostics for Energetic-Material Ignition Mechanisms:

    Office of Scientific and Technical Information (OSTI)

    Tools for Physics-Based Model Development. (Technical Report) | SciTech Connect Technical Report: Ultrafast Laser Diagnostics for Energetic-Material Ignition Mechanisms: Tools for Physics-Based Model Development. Citation Details In-Document Search Title: Ultrafast Laser Diagnostics for Energetic-Material Ignition Mechanisms: Tools for Physics-Based Model Development. We present the results of an LDRD project to develop diagnostics to perform fundamental measurements of material properties

  15. Delivering Innovations That Create Jobs: National Lab Ignites Business for

    Office of Energy Efficiency and Renewable Energy (EERE) Indexed Site

    Entrepreneurs | Department of Energy Delivering Innovations That Create Jobs: National Lab Ignites Business for Entrepreneurs Delivering Innovations That Create Jobs: National Lab Ignites Business for Entrepreneurs November 17, 2011 - 1:59pm Addthis DEP Shape Memory Therapeutics, Inc. is working to treat aneurysms with exclusively licensed LLNL-developed polymer materials that "remember" their shape. LLNL is a leader in the development of shape memory polymers, for use in medical

  16. Theory of hydro-equivalent ignition for inertial fusion and its applications to OMEGA and the National Ignition Facility

    SciTech Connect (OSTI)

    Nora, R.; Betti, R.; Bose, A.; Woo, K. M.; Christopherson, A. R.; Meyerhofer, D. D.; McCrory, R. L.

    2014-05-15

    The theory of ignition for inertial confinement fusion capsules [R. Betti et al., Phys. Plasmas 17, 058102 (2010)] is used to assess the performance requirements for cryogenic implosion experiments on the Omega Laser Facility. The theory of hydrodynamic similarity is developed in both one and two dimensions and tested using multimode hydrodynamic simulations with the hydrocode DRACO [P. B. Radha et al., Phys. Plasmas 12, 032702 (2005)] of hydro-equivalent implosions (implosions with the same implosion velocity, adiabat, and laser intensity). The theory is used to scale the performance of direct-drive OMEGA implosions to the National Ignition Facility (NIF) energy scales and determine the requirements for demonstrating hydro-equivalent ignition on OMEGA. Hydro-equivalent ignition on OMEGA is represented by a cryogenic implosion that would scale to ignition on the NIF at 1.8?MJ of laser energy symmetrically illuminating the target. It is found that a reasonable combination of neutron yield and areal density for OMEGA hydro-equivalent ignition is 3 to 6??10{sup 13} and ?0.3?g/cm{sup 2}, respectively, depending on the level of laser imprinting. This performance has not yet been achieved on OMEGA.

  17. The development of laser ignited deflagration-to-detonation transition (DDT) detonators and pyrotechnic actuators

    SciTech Connect (OSTI)

    Merson, J.A.; Salas, F.J.

    1994-05-01

    The use of laser ignited explosive components has been recognized as a safety enhancement over existing electrical explosive devices (EEDs). Sandia has been pursuing the development of optical ordnance for many years with recent emphasis on developing optical deflagration-to-detonation (DDT) detonators and pyrotechnic actuators. These low energy optical ordnance devices can be ignited with either a semiconductor diode laser, laser diode arrays or a solid state rod laser. By using a semiconductor laser diode, the safety improvement can be made without sacrificing performance since the input energy required for the laser diode and the explosive output are similar to existing electrical systems. The use of higher powered laser diode arrays or rod lasers may have advantages in fast DDT applications or lossy optical environments such as long fiber applications and applications with numerous optical connectors. Recent results from our continued study of optical ignition of explosive and pyrotechnic materials are presented. These areas of investigation can be separated into three different margin categories: (1) the margin relative to intended inputs ( i.e. powder performance as a function of laser input variation), (2) the margin relative to anticipated environments (i.e. powder performance as a function of thermal environment variation), and (3) the margin relative to unintended environments (i.e. responses to abnormal environments or safety).

  18. The development of laser ignited deflagration-to-detonation transition (DDT) detonators and pyrotechnic actuators

    SciTech Connect (OSTI)

    Merson, J.A.; Salas, F.J.; Harlan, J.G.

    1993-11-01

    The use of laser ignited explosive components has been recognized as a safety enhancement over existing electrical explosive devices (EEDs). Sandia has been pursuing the development of optical ordnance for many years with recent emphasis on developing optical deflagration-to-detonation (DDT) detonators and pyrotechnic actuators. These low energy optical ordnance devices can be ignited with either a semiconductor diode laser, laser diode arrays or a solid state rod laser. By using a semiconductor laser diode, the safety improvement can be made without sacrificing performance since the input energy required for the laser diode and the explosive output are similar to existing electrical systems. The use of higher powered laser diode arrays or rod lasers may have advantages in fast DDT applications or lossy optical environments such as long fiber applications and applications with numerous optical connectors. Recent results from our continued study of optical ignition of explosive and pyrotechnic materials are presented. These areas of investigation can be separated into three different margin categories: (1) the margin relative to intended inputs (i.e. powder performance as a function of laser input variation), (2) the margin relative to anticipated environments (i.e. powder performance as a function of thermal environment variation), and (3) the margin relative to unintended environments (i.e. responses to abnormal environments or safety).

  19. Chemical kinetic analysis of hydrogen-air ignition and reaction times

    SciTech Connect (OSTI)

    Rogers, R.C.; Schexnayder, C.J. Jr.

    1981-07-01

    An anaytical study of hydrogen air kinetics was performed. Calculations were made over a range of pressure from 0.2 to 4.0 atm, temperatures from 850 to 2000 K, and mixture equivalence ratios from 0.2 to 2.0. The finite rate chemistry model included 60 reactions in 20 species of the H2-O2-N2 system. The calculations also included an assessment of how small amounts of the chemicals H2O, NOx, H2O2, and O3 in the initial mixture affect ignition and reaction times, and how the variation of the third body efficiency of H2O relative of N2 in certain key reactions may affect reaction time. The results indicate that for mixture equivalence ratios between 0.5 and 1.7, ignition times are nearly constant however, the presence of H2O and NO can have significant effects on ignition times, depending on the mixture temperature. Reaction time is dominantly influenced by pressure but is nearly independent of initial temperature, equivalence ratio, and the addition of chemicals. Effects of kinetics on reaction at supersonic combustor conditions are discussed.

  20. Fuel burner having a intermittent pilot with pre-ignition testing

    SciTech Connect (OSTI)

    Peterson, S.M.

    1991-07-30

    This patent describes improvement in a fuel burner having a main burner and a pilot burner for lighting the main burner, an electrically-powered igniter for lighting the pilot burner, a source of electric energy, an igniter power supply receiving a demand signal and supplying power to the igniter responsive to the demand signal, a pilot sensor adjacent to the pilot burner and supplying a pilot signal responsive to presence of a pilot flame, and a main burner valve controlling flow of fuel to the main burner and opening responsive to the pilot signal. The improvement comprises: a pilot burner valve controlling flow of fuel to the pilot burner and opening responsive to a pilot valve control signal; igniter sensing means in sensing relation to the igniter for providing an igniter signal responsive to operation of the igniter; and pilot valve control means receiving the igniter signal, for providing the pilot valve control signal responsive to the igniter signal.

  1. Proceedings of the 1996 spring technical conference of the ASME Internal Combustion Engine Division. Volume 2: Engine design and engine systems; ICE-Volume 26-2

    SciTech Connect (OSTI)

    Uzkan, T.

    1996-12-31

    Although the cost of the petroleum crude has not increased much within the last decade, the drive to develop internal combustion engines is still continuing. The basic motivation of this drive is to reduce both emissions and costs. Recent developments in computer chip production and information management technology have opened up new applications in engine controls and monitoring. The development of new information is continuing at a rapid pace. Some of these research and development results were presented at the 1996 Spring Technical Conference of the ASME Internal Combustion Engine Division in Youngstown, Ohio, April 21--24, 1996. The papers presented covered various aspects of the design, development, and application of compression ignition and spark ignition engines. The conference was held at the Holiday Inn Metroplex Complex and hosted by Altronic Incorporated of Girard, Ohio. The written papers submitted to the conference have been published in three conference volumes. Volume 2 includes the papers on the topics of engine design, engine systems, and engine user experience.

  2. Optimally Controlled Flexible Fuel Powertrain System

    SciTech Connect (OSTI)

    Hakan Yilmaz; Mark Christie; Anna Stefanopoulou

    2010-12-31

    The primary objective of this project was to develop a true Flex Fuel Vehicle capable of running on any blend of ethanol from 0 to 85% with reduced penalty in usable vehicle range. A research and development program, targeting 10% improvement in fuel economy using a direct injection (DI) turbocharged spark ignition engine was conducted. In this project a gasoline-optimized high-technology engine was considered and the hardware and configuration modifications were defined for the engine, fueling system, and air path. Combined with a novel engine control strategy, control software, and calibration this resulted in a highly efficient and clean FFV concept. It was also intended to develop robust detection schemes of the ethanol content in the fuel integrated with adaptive control algorithms for optimized turbocharged direct injection engine combustion. The approach relies heavily on software-based adaptation and optimization striving for minimal modifications to the gasoline-optimized engine hardware system. Our ultimate objective was to develop a compact control methodology that takes advantage of any ethanol-based fuel mixture and not compromise the engine performance under gasoline operation.

  3. Advantages of Oxygenates Fuels over Gasoline in Direct Injection...

    Office of Energy Efficiency and Renewable Energy (EERE) Indexed Site

    Advantages of Oxygenates Fuels over Gasoline in Direct Injection Spark Ignition Engines Advantages of Oxygenates Fuels over Gasoline in Direct Injection Spark Ignition Engines ...

  4. National Ignition Facility Configuration Management Plan

    SciTech Connect (OSTI)

    Cabral, S G; Moore, T L

    2002-10-01

    This Configuration Management Plan (CMP) describes the technical and administrative management process for controlling the National Ignition Facility (NIF) Project configuration. The complexity of the NIF Project (i.e., participation by multiple national laboratories and subcontractors involved in the development, fabrication, installation, and testing of NIF hardware and software, as well as construction and testing of Project facilities) requires implementation of the comprehensive configuration management program defined in this plan. A logical schematic illustrating how the plan functions is provided in Figure 1. A summary of the process is provided in Section 4.0, Configuration Change Control. Detailed procedures that make up the overall process are referenced. This CMP is consistent with guidance for managing a project's configuration provided in Department of Energy (DOE) Order 430.1, Guide PMG 10, ''Project Execution and Engineering Management Planning''. Configuration management is a formal discipline comprised of the following four elements: (1) Identification--defines the functional and physical characteristics of a Project and uniquely identifies the defining requirements. This includes selection of components of the end product(s) subject to control and selection of the documents that define the project and components. (2) Change management--provides a systematic method for managing changes to the project and its physical and functional configuration to ensure that all changes are properly identified, assessed, reviewed, approved, implemented, tested, and documented. (3) Data management--ensures that necessary information on the project and its end product(s) is systematically recorded and disseminated for decision-making and other uses. Identifies, stores and controls, tracks status, retrieves, and distributes documents. (4) Assessments and validation--ensures that the planned configuration requirements match actual physical configurations and approved changes are implemented according to the change requirements documents.

  5. Controlling the Electrostatic Discharge Ignition Sensitivity of Composite Energetic Materials Using Carbon Nanotube Additives

    SciTech Connect (OSTI)

    Kade H. Poper; Eric S. Collins; Michelle L. Pantoya; Michael Daniels

    2014-10-01

    Powder energetic materials are highly sensitive to electrostatic discharge (ESD) ignition. This study shows that small concentrations of carbon nanotubes (CNT) added to the highly reactive mixture of aluminum and copper oxide (Al + CuO) significantly reduces ESD ignition sensitivity. CNT act as a conduit for electric energy, bypassing energy buildup and desensitizing the mixture to ESD ignition. The lowest CNT concentration needed to desensitize ignition is 3.8 vol.% corresponding to percolation corresponding to an electrical conductivity of 0.04 S/cm. Conversely, added CNT increased Al + CuO thermal ignition sensitivity to a hot wire igniter.

  6. Electrical Cable Testing by Pulse-Arrested Spark Discharge (PASD) - Energy

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Innovation Portal Startup America Startup America Industrial Technologies Industrial Technologies Energy Storage Energy Storage Electricity Transmission Electricity Transmission Building Energy Efficiency Building Energy Efficiency Find More Like This Return to Search Electrical Cable Testing by Pulse-Arrested Spark Discharge (PASD) Sandia National Laboratories Contact SNL About This Technology Publications: PDF Document Publication Market Sheet (796 KB) Technology Marketing SummarySandia

  7. Vehicle Technologies Office Merit Review 2014: The Application of High Energy Ignition and Boosting/Mixing Technology to Increase Fuel Economy in Spark Ignition Gasoline Engines by Increasing EGR Dilution Capability

    Broader source: Energy.gov [DOE]

    Presentation given by General Motors LLC at 2014 DOE Hydrogen and Fuel Cells Program and Vehicle Technologies Office Annual Merit Review and Peer Evaluation Meeting about the application of high...

  8. Methane ignition catalyzed by in situ generated palladium nanoparticles

    SciTech Connect (OSTI)

    Shimizu, T.; Abid, A.D.; Poskrebyshev, G.; Wang, H. [Department of Aerospace and Mechanical Engineering, University of Southern California, Los Angeles, CA 90089 (United States); Nabity, J.; Engel, J.; Yu, J. [TDA Research, Inc., 12345 W. 52nd Ave, Wheat Ridge, CO 80033 (United States); Wickham, D. [Reaction Systems, LLC, 19039 E. Plaza Drive, Suite 290, Parker, CO 80134 (United States); Van Devener, B.; Anderson, S.L. [Department of Chemistry, University of Utah, Salt Lake City, UT 84112 (United States); Williams, S. [Air Force Research Laboratory, Mail Stop RZA, 1950 Fifth Street, WPAFB, OH 45433 (United States)

    2010-03-15

    Catalytic ignition of methane over the surfaces of freely-suspended and in situ generated palladium nanoparticles was investigated experimentally and numerically. The experiments were conducted in a laminar flow reactor. The palladium precursor was a compound (Pd(THD){sub 2}, THD: 2,2,6,6-tetramethyl-3,5-heptanedione) dissolved in toluene and injected into the flow reactor as a fine aerosol, along with a methane-oxygen-nitrogen mixture. For experimental conditions chosen in this study, non-catalytic, homogeneous ignition was observed at a furnace temperature of {proportional_to}1123 K, whereas ignition of the same mixture with the precursor was found to be {proportional_to}973 K. In situ production of Pd/PdO nanoparticles was confirmed by scanning mobility, transmission electron microscopy and X-ray photoelectron spectroscopy analyses of particles collected at the reactor exit. The catalyst particle size distribution was log-normal. Depending on the precursor loading, the median diameter ranged from 10 to 30 nm. The mechanism behind catalytic ignition was examined using a combined gas-phase and gas-surface reaction model. Simulation results match the experiments closely and suggest that palladium nanocatalyst significantly shortens the ignition delay times of methane-air mixtures over a wide range of conditions. (author)

  9. WILDFIRE IGNITION RESISTANCE ESTIMATOR WIZARD SOFTWARE DEVELOPMENT REPORT

    SciTech Connect (OSTI)

    Phillips, M.; Robinson, C.; Gupta, N.; Werth, D.

    2012-10-10

    This report describes the development of a software tool, entitled WildFire Ignition Resistance Estimator Wizard (WildFIRE Wizard, Version 2.10). This software was developed within the Wildfire Ignition Resistant Home Design (WIRHD) program, sponsored by the U. S. Department of Homeland Security, Science and Technology Directorate, Infrastructure Protection & Disaster Management Division. WildFIRE Wizard is a tool that enables homeowners to take preventive actions that will reduce their homes vulnerability to wildfire ignition sources (i.e., embers, radiant heat, and direct flame impingement) well in advance of a wildfire event. This report describes the development of the software, its operation, its technical basis and calculations, and steps taken to verify its performance.

  10. The effect of shock dynamics on compressibility of ignition-scale National Ignition Facility implosions

    DOE Public Access Gateway for Energy & Science Beta (PAGES Beta)

    Zylstra, A. B.; Frenje, J. A.; Séguin, F. H.; Hicks, D. G.; Dewald, E. L.; Robey, H. F.; Rygg, J. R.; Meezan, N. B.; Rosenberg, M. J.; Rinderknecht, H. G.; et al

    2014-11-03

    The effects of shock dynamics on compressibility of indirect-drive ignition-scale surrogate implosions, CH shells filled with D3He gas, have been studied using charged-particle spectroscopy. Spectral measurements of D3He protons produced at the shock-bang time probe the shock dynamics and in-flight characteristics of an implosion. The proton shock yield is found to vary by over an order of magnitude. A simple model relates the observed yield to incipient hot-spot adiabat, suggesting that implosions with rapid radiation-power increase during the main drive pulse may have a 2x higher hot-spot adiabat, potentially reducing compressibility. A self-consistent 1-D implosion model was used to infermore » the areal density (pR) and the shell center-of-mass radius (Rcm) from the downshift of the shock-produced D3He protons. The observed pR at shock-bang time is substantially higher for implosions, where the laser drive is on until near the compression bang time ('short-coast'), while longer-coasting implosions have lower pR. This corresponds to a much larger temporal difference between the shock- and compression-bang time in the long-coast implosions (~800 ps) than in the short-coast (~400 ps); this will be verified with a future direct bang-time diagnostic. This model-inferred differential bang time contradicts radiation-hydrodynamic simulations, which predict constant 700–800 ps differential independent of coasting time. This result is potentially explained by uncertainties in modeling late-time ablation drive on the capsule. In an ignition experiment, an earlier shock-bang time resulting in an earlier onset of shell deceleration, potentially reducing compression and, thus, fuel pR.« less

  11. National Ignition Facility & Photon Science NIF Fun Facts

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    7 National Ignition Facility & Photon Science NIF Fun Facts niF Fun Facts The National Ignition Facility (NIF), became operational in march 2009. Planning began in the early 1990s, and ground was broken for the facility on may 29, 1997-12 years to the day before NIF's dedication. Construction Construction of the main NIF building, known as the "conventional facility," was completed in 2001. * Building height: 10 stories * Building width: 3 football fields * Cubic meters of soil

  12. Correlating cookoff violence with pre-ignition damage.

    SciTech Connect (OSTI)

    Wente, William Baker; Hobbs, Michael L.; Kaneshige, Michael Jiro

    2010-03-01

    Predicting the response of energetic materials during accidents, such as fire, is important for high consequence safety analysis. We hypothesize that responses of ener-getic materials before and after ignition depend on factors that cause thermal and chemi-cal damage. We have previously correlated violence from PETN to the extent of decom-position at ignition, determined as the time when the maximum Damkoehler number ex-ceeds a threshold value. We seek to understand if our method of violence correlation ap-plies universally to other explosive starting with RDX.

  13. Exhaust gas recirculation in a homogeneous charge compression ignition engine

    DOE Patents [OSTI]

    Duffy, Kevin P. (Metamora, IL); Kieser, Andrew J. (Morton, IL); Rodman, Anthony (Chillicothe, IL); Liechty, Michael P. (Chillicothe, IL); Hergart, Carl-Anders (Peoria, IL); Hardy, William L. (Peoria, IL)

    2008-05-27

    A homogeneous charge compression ignition engine operates by injecting liquid fuel directly in a combustion chamber, and mixing the fuel with recirculated exhaust and fresh air through an auto ignition condition of the fuel. The engine includes at least one turbocharger for extracting energy from the engine exhaust and using that energy to boost intake pressure of recirculated exhaust gas and fresh air. Elevated proportions of exhaust gas recirculated to the engine are attained by throttling the fresh air inlet supply. These elevated exhaust gas recirculation rates allow the HCCI engine to be operated at higher speeds and loads rendering the HCCI engine a more viable alternative to a conventional diesel engine.

  14. Features of a point design for fast ignition

    SciTech Connect (OSTI)

    Tabak, M; Clark, D; Town, R J; Key, M H; Amendt, P; Ho, D; Meeker, D J; Shay, H D; Lasinski, B F; Kemp, A; Divol, L; Mackinnon, A J; Patel, P; Strozzi, D; Grote, D P

    2009-10-26

    Fast Ignition is an inertial fusion scheme in which fuel is first assembled and then heated to the ignition temperature with an external heating source. In this note we consider cone and shell implosions where the energy supplied by short pulse lasers is transported to the fuel by electrons. We describe possible failure modes for this scheme and how to overcome them. In particular, we describe two sources of cone tip failure, an axis jet driven from the compressed fuel mass and hard photon preheat leaking through the implosion shell, and laser prepulse that can change the position of laser absorption and the angular distribution of the emitted electrons.

  15. High-speed laser-induced fluorescence and spark plug absorption sensor diagnostics for mixing and combustion studies in engines

    SciTech Connect (OSTI)

    Cundy, Michael; Schucht, Torsten; Thiele, Olaf; Sick, Volker

    2009-02-01

    Simultaneous high-speed in-cylinder measurements of laser-induced fluorescence of biacetyl as a fuel tracer and mid-infrared broadband absorption of fuel and combustion products (water and carbon dioxide) using a spark plug probe are compared in an optical engine. The study addresses uncertainties and the applicability of absorption measurements at a location slightly offset to the spark plug when information about mixing at the spark plug is desired. Absorbance profiles reflect important engine operation events, such as valve opening and closing, mixing, combustion, and outgassing from crevices.

  16. Solar Project to Spark Students' Studies, School's Savings |...

    Office of Energy Efficiency and Renewable Energy (EERE) Indexed Site

    stands out, saves energy Arizona Teachers Prepare Students for Green Economy View of the solar panel system atop Warren Easton Senior High School in New Orleans. | Photo courtesy...

  17. Optimization of the process of plasma ignition of coal

    SciTech Connect (OSTI)

    Peregudov, V.S.

    2009-04-15

    Results are given of experimental and theoretical investigations of plasma ignition of coal as a result of its thermochemical preparation in application to the processes of firing up a boiler and stabilizing the flame combustion. The experimental test bed with a commercial-scale burner is used for determining the conditions of plasma ignition of low-reactivity high-ash anthracite depending on the concentration of coal in the air mixture and velocity of the latter. The calculations produce an equation (important from the standpoint of practical applications) for determining the energy expenditure for plasma ignition of coal depending on the basic process parameters. The tests reveal the difficulties arising in firing up a boiler with direct delivery of pulverized coal from the mill to furnace. A scheme is suggested, which enables one to reduce the energy expenditure for ignition of coal and improve the reliability of the process of firing up such a boiler. Results are given of calculation of plasma thermochemical preparation of coal under conditions of lower concentration of oxygen in the air mixture.

  18. CO/sub 2/-laser ignition of DAPP targets

    SciTech Connect (OSTI)

    Brannon, P.J.

    1981-07-01

    A pulse derived by shuttering a CO/sub 2/ laser operating in the cw mode has been used to ignite a diallyl phthalate pyrotechnic (DAPP) material. Data from this work along with some data taken earlier, while operating the laser in the pulse mode, are presented. When operating in the cw mode, a pulse is mechanically chopped out of the beam and focussed onto the DAPP material. It was found that the shuttered cw mode of operation gives a more reproducible pulse and a more accurate determination of the incident energy than the pulse mode does. The pulse widths for threshold ignition (50% ignitions) at different power levels have been determined for 254 and 127 mm-focal-length lenses which were used to focus the beam on the target. It was also found that targets could be penetrated without ignition of the DAPP material. A 2.54 mm-thick DAPP target is penetrated by the laser beam if the energy per unit area exceeds 29 +1 J/mm/sup 2/. Based on this study, recommendations are given for improving the present test procedures used for DAPP material.

  19. Drying low rank coal and retarding spontaneous ignition

    SciTech Connect (OSTI)

    Bixel, J.C.; Bellow, E.J.; Heaney, W.F.; Facinelli, S.H.

    1989-05-09

    A method is described of producing a dried particulate coal fuel having a reduced tendency to ignite spontaneously comprising spraying and intimately mixing the dried coal with an aqueous emulsion of a material selected from the group consisting of foots oils, petrolatum filtrate, and hydrocracker recycle oil.

  20. Director of the National Ignition Facility, Lawrence Livermore National

    National Nuclear Security Administration (NNSA)

    Laboratory | National Nuclear Security Administration the National Ignition Facility, Lawrence Livermore National Laboratory | National Nuclear Security Administration Facebook Twitter Youtube Flickr RSS People Mission Managing the Stockpile Preventing Proliferation Powering the Nuclear Navy Emergency Response Recapitalizing Our Infrastructure Countering Nuclear Terrorism About Our Programs Our History Who We Are Our Leadership Our Locations Budget Our Operations Library Bios Congressional

  1. Properties of laser radiation scattering by a laser-induced spark plasma revisited after 40 years

    SciTech Connect (OSTI)

    Malyutin, A A

    2008-05-31

    Experimental studies of a laser-induced spark produced in air by 1.05-{mu}m, 100-ns pulses with spatial TEM{sub 00}, TEM{sub 01} and TEM{sub 02} modes are described. It is found that when the spark is observed at an angle of 90{sup 0} to the laser beam axis, the scattered radiation has the maximal intensity outside the beam waist. The intensity ratio of the scattered laser radiation for two orthogonal polarisations is {approx}100, and the spatial structures of their depolarisation considerably differ. These properties are explained by using a model of the Fresnel reflection from the spherical front of the plasma-undisturbed gas interface. (laser radiation scattering)

  2. Peculiarities of the angular distribution of laser radiation intensity scattered by laser-spark plasma in air

    SciTech Connect (OSTI)

    Malyutin, A A; Podvyaznikov, V A; Chevokin, V K

    2010-02-28

    The spatiotemporal study of the diagram of laser radiation scattering by the laser-spark plasma produced by 3-ns and 50-ns pulses is performed. It is shown that radiation appearing outside the laser beam cone is scattered during the first one - two nanoseconds after the air breakdown, when the spark plasma is located in the vicinity of the laser beam waist and has a shape close to spherical.

  3. High Efficiency, Low Emissions Homogeneous Charge Compression Ignition (HCCI) Engines

    SciTech Connect (OSTI)

    2011-01-31

    This is the final report of the High Efficiency Clean Combustion (HECC) Research Program for the U.S. Department of Energy. Work under this co-funded program began in August 2005 and finished in July 2010. The objective of this program was to develop and demonstrate a low emission, high thermal efficiency engine system that met 2010 EPA heavy-duty on-highway truck emissions requirements (0.2g/bhp-hr NOx, 0.14g/bhp-hr HC and 0.01g/bhp-hr PM) with a thermal efficiency of 46%. To achieve this goal, development of diesel homogenous charge compression ignition (HCCI) combustion was the chosen approach. This report summarizes the development of diesel HCCI combustion and associated enabling technologies that occurred during the HECC program between August 2005 and July 2010. This program showed that although diesel HCCI with conventional US diesel fuel was not a feasible means to achieve the program objectives, the HCCI load range could be increased with a higher volatility, lower cetane number fuel, such as gasoline, if the combustion rate could be moderated to avoid excessive cylinder pressure rise rates. Given the potential efficiency and emissions benefits, continued research of combustion with low cetane number fuels and the effects of fuel distillation are recommended. The operation of diesel HCCI was only feasible at part-load due to a limited fuel injection window. A 4% fuel consumption benefit versus conventional, low-temperature combustion was realized over the achievable operating range. Several enabling technologies were developed under this program that also benefited non-HCCI combustion. The development of a 300MPa fuel injector enabled the development of extended lifted flame combustion. A design methodology for minimizing the heat transfer to jacket water, known as precision cooling, will benefit conventional combustion engines, as well as HCCI engines. An advanced combustion control system based on cylinder pressure measurements was developed. A Well-to-wheels analysis of the energy flows in a mobile vehicle system and a 2nd Law thermodynamic analysis of the engine system were also completed under this program.

  4. Software solutions manage the definition, operation, maintenance and configuration control of the National Ignition Facility

    SciTech Connect (OSTI)

    Dobson, D; Churby, A; Krieger, E; Maloy, D; White, K

    2011-07-25

    The National Ignition Facility (NIF) is the world's largest laser composed of millions of individual parts brought together to form one massive assembly. Maintaining control of the physical definition, status and configuration of this structure is a monumental undertaking yet critical to the validity of the shot experiment data and the safe operation of the facility. The NIF business application suite of software provides the means to effectively manage the definition, build, operation, maintenance and configuration control of all components of the National Ignition Facility. State of the art Computer Aided Design software applications are used to generate a virtual model and assemblies. Engineering bills of material are controlled through the Enterprise Configuration Management System. This data structure is passed to the Enterprise Resource Planning system to create a manufacturing bill of material. Specific parts are serialized then tracked along their entire lifecycle providing visibility to the location and status of optical, target and diagnostic components that are key to assessing pre-shot machine readiness. Nearly forty thousand items requiring preventive, reactive and calibration maintenance are tracked through the System Maintenance & Reliability Tracking application to ensure proper operation. Radiological tracking applications ensure proper stewardship of radiological and hazardous materials and help provide a safe working environment for NIF personnel.

  5. Simulation of hydrogen and hydrogen-assisted propane ignition in Pt catalyzed microchannel

    SciTech Connect (OSTI)

    Seshadri, Vikram; Kaisare, Niket S.

    2010-11-15

    This paper deals with self-ignition of catalytic microburners from ambient cold-start conditions. First, reaction kinetics for hydrogen combustion is validated with experimental results from the literature, followed by validation of a simplified pseudo-2D microburner model. The model is then used to study the self-ignition behavior of lean hydrogen/air mixtures in a Platinum-catalyzed microburner. Hydrogen combustion on Pt is a very fast reaction. During cold start ignition, hydrogen conversion reaches 100% within the first few seconds and the reactor dynamics are governed by the ''thermal inertia'' of the microburner wall structure. The self-ignition property of hydrogen can be used to provide the energy required for propane ignition. Two different modes of hydrogen-assisted propane ignition are considered: co-feed mode, where the microburner inlet consists of premixed hydrogen/propane/air mixtures; and sequential feed mode, where the inlet feed is switched from hydrogen/air to propane/air mixtures after the microburner reaches propane ignition temperature. We show that hydrogen-assisted ignition is equivalent to selectively preheating the inlet section of the microburner. The time to reach steady state is lower at higher equivalence ratio, lower wall thermal conductivity, and higher inlet velocity for both the ignition modes. The ignition times and propane emissions are compared. Although the sequential feed mode requires slightly higher amount of hydrogen, the propane emissions are at least an order of magnitude lower than the other ignition modes. (author)

  6. Near-critical phase explosion promoting breakdown plasma ignition during laser ablation of graphite

    SciTech Connect (OSTI)

    Ionin, A. A.; Kudryashov, S. I.; Seleznev, L. V.

    2010-07-15

    Removal rate, air shock, and ablative recoil pressure parameters were measured as a function of laser intensity I{sub peak} during nanosecond laser ablation of graphite. Surface vaporization of molten graphite at low intensities I{sub peak}<0.15 GW/cm{sup 2} was observed to transform into its near-critical phase explosion (intense homogeneous boiling) at the threshold intensity I{sub PE}approx =0.15 GW/cm{sup 2} in the form of a drastic, correlated rise of removal rate, air shock, and ablative recoil pressure magnitudes. Just above this threshold (I{sub peak}>=0.25 GW/cm{sup 2}), the explosive mass removal ended up with saturation of the removal rate, much slower increase of the air and recoil pressure magnitudes, and appearance of a visible surface plasma spark. In this regime, the measured far-field air shock pressure amplitude exhibits a sublinear dependence on laser intensity (propor toI{sub peak}{sup 4/9}), while the source plasma shock pressure demonstrates a sublinear trend (propor toI{sub peak}{sup 3/4}), both indicating the subcritical character of the plasma. Against expectations, in this regime the plasma recoil pressure increases versus I{sub peak} superlinearly (propor toI{sub peak}{sup 1.1}), rather than sublinearly (propor toI{sub peak}{sup 3/4}), with the mentioned difference related to the intensity-dependent initial spatial plasma dimensions within the laser waist on the graphite surface and to the plasma formation time during the heating laser pulse (overall, the pressure source effect). The strict coincidence of the phase explosion, providing high (kbar) hydrodynamic pressures of ablation products, and the ignition of ablative laser plasma in the carbon plume may indicate the ablative pressure-dependent character of the underlying optical breakdown at the high plume pressures, initiating the plasma formation. The experimental data evidence that the spatiotemporal extension of the plasma in the laser plume and ambient air during the heating laser pulse is supported by fast lateral electron and radiative heat conduction (laser-supported combustion wave regime), rather than by propagation of a strong shock wave (laser-supported detonation wave regime).

  7. A Robust In-Situ Warp-Correction Algorithm For VISAR Streak Camera Data at the National Ignition Facility

    SciTech Connect (OSTI)

    Labaria, G; Warrick, A L; Celliers, P M; Kalantar, D H

    2015-01-12

    The National Ignition Facility (NIF) at the Lawrence Livermore National Laboratory is a 192-beam pulsed laser system for high-energy-density physics experiments. Sophisticated diagnostics have been designed around key performance metrics to achieve ignition. The Velocity Interferometer System for Any Reflector (VISAR) is the primary diagnostic for measuring the timing of shocks induced into an ignition capsule. The VISAR system utilizes three streak cameras; these streak cameras are inherently nonlinear and require warp corrections to remove these nonlinear eff ects. A detailed calibration procedure has been developed with National Security Technologies (NSTec) and applied to the camera correction analysis in production. However, the camera nonlinearities drift over time, aff ecting the performance of this method. An in-situ fi ber array is used to inject a comb of pulses to generate a calibration correction in order to meet the timing accuracy requirements of VISAR. We develop a robust algorithm for the analysis of the comb calibration images to generate the warp correction that is then applied to the data images. Our algorithm utilizes the method of thin-plate splines (TPS) to model the complex nonlinear distortions in the streak camera data. In this paper, we focus on the theory and implementation of the TPS warp-correction algorithm for the use in a production environment.

  8. Energy Department Solid-State Lighting Efforts Spark New Paradigm

    Broader source: Energy.gov [DOE]

    Breakthroughs in solid-state lighting (SSL) technology, driven in part by Energy Department research investments, are leading to sweeping changes in the way lighting experts view the vast economic potential of future lighting systems and their growing benefits to society.

  9. Calculating the dynamics of High Explosive Violent Response (HEVR) after ignition

    SciTech Connect (OSTI)

    Reaugh, J E

    2008-10-15

    We are developing models to describe the circumstances when molecular and composite explosives undergo a rapid release of energy without detonating, and to describe the evolution of the energy release. The models also apply to the behavior of rocket propellants subject to mechanical insult, whether for accidents (Hazards) or the suite of standardized tests used to assess whether the system can be designated an Insensitive Munition (IM). In the applications described here, we are studying a UK-developed HMX (1,3,5,7-tetranitro-1,3,5,7-tetraazacyclooctane) explosive, which is 91% by weight HMX and 9% binder-plasticizer. Most explosives and propellants, when subjected to a mechanical insult such as a drop or impact that is well below the threshold for detonation, have been observed to react. In some circumstances the reaction can be violent. This behavior is known as High Explosive Violent Response (HEVR). Fundamental to our model is the observation that the mechanical insult produces damage in a volume of the explosive near the trajectory of the impactor. The damage is manifest as surface area through the creation of cracks and fragments, and also as porosity through the separation of crack faces and isolation of the fragments. Open porosity permits a flame to spread easily and so ignite the newly formed surface area. The additional surface area leads to a direct increase in the mass-burning rate. As the kinetic energy and power of the insult increases, the degree of damage and the volume of damage both increase. Upon a localized ignition, the flame spreads to envelop the damaged volume, and the pressure rises at an accelerated rate until neither mechanical strength nor inertial confinement can successfully contain the pressure. The confining structure begins to expand. This reduces the pressure and may even extinguish the flame. Both the mass of explosive involved and the rate at which the gas is produced contribute to each of several different measures of violence. Such measures include damage to the confinement, the velocity and fragment size distributions from what was the confinement, and air blast. In the first phase (advisory) model described in [1], the surface to volume ratio and the ignition parameter are calibrated by comparison with experiments using the UK explosive. In order to achieve the second phase (interactive) model, and so calculate the pressure developed and the velocity imparted to the confinement, we need to calculate the spread of the ignition front, the subsequent burn behavior behind that front, and the response of unburned and partially burned explosive to pressurization. A preliminary model to do such calculations is described here.

  10. Inertial Confinement Fusion and the National Ignition Facility (NIF)

    SciTech Connect (OSTI)

    Ross, P.

    2012-08-29

    Inertial confinement fusion (ICF) seeks to provide sustainable fusion energy by compressing frozen deuterium and tritium fuel to extremely high densities. The advantages of fusion vs. fission are discussed, including total energy per reaction and energy per nucleon. The Lawson Criterion, defining the requirements for ignition, is derived and explained. Different confinement methods and their implications are discussed. The feasibility of creating a power plant using ICF is analyzed using realistic and feasible numbers. The National Ignition Facility (NIF) at Lawrence Livermore National Laboratory is shown as a significant step forward toward making a fusion power plant based on ICF. NIF is the worlds largest laser, delivering 1.8 MJ of energy, with a peak power greater than 500 TW. NIF is actively striving toward the goal of fusion energy. Other uses for NIF are discussed.

  11. Nuclear diagnostics for the National Ignition Facility (invited)

    SciTech Connect (OSTI)

    Murphy, Thomas J.; Barnes, Cris W.; Berggren, R. R.; Bradley, P.; Caldwell, S. E.; Chrien, R. E.; Faulkner, J. R.; Gobby, P. L.; Hoffman, N.; Jimerson, J. L.

    2001-01-01

    The National Ignition Facility (NIF), currently under construction at the Lawrence Livermore National Laboratory, will provide unprecedented opportunities for the use of nuclear diagnostics in inertial confinement fusion experiments. The completed facility will provide 2 MJ of laser energy for driving targets, compared to the approximately 40 kJ that was available on Nova and the approximately 30 kJ available on Omega. Ignited NIF targets are anticipated to produce up to 10{sup 19} DT neutrons. In addition to a basic set of nuclear diagnostics based on previous experience, these higher NIF yields are expected to allow innovative nuclear diagnostic techniques to be utilized, such as neutron imaging, recoil proton techniques, and gamma-ray-based reaction history measurements.

  12. High Efficiency GDI Engine Research, with Emphasis on Ignition Systems

    Broader source: Energy.gov [DOE]

    2013 DOE Hydrogen and Fuel Cells Program and Vehicle Technologies Program Annual Merit Review and Peer Evaluation Meeting

  13. High load operation in a homogeneous charge compression ignition engine

    DOE Patents [OSTI]

    Duffy, Kevin P. (Metamora, IL); Kieser, Andrew J. (Morton, IL); Liechty, Michael P. (Chillicothe, IL); Hardy, William L. (Peoria, IL); Rodman, Anthony (Chillicothe, IL); Hergart, Carl-Anders (Peoria, IL)

    2008-12-23

    A homogeneous charge compression ignition engine is set up by first identifying combinations of compression ratio and exhaust gas percentages for each speed and load across the engines operating range. These identified ratios and exhaust gas percentages can then be converted into geometric compression ratio controller settings and exhaust gas recirculation rate controller settings that are mapped against speed and load, and made available to the electronic

  14. Groundbreaking at National Ignition Facility | National Nuclear Security

    National Nuclear Security Administration (NNSA)

    Administration at National Ignition Facility | National Nuclear Security Administration Facebook Twitter Youtube Flickr RSS People Mission Managing the Stockpile Preventing Proliferation Powering the Nuclear Navy Emergency Response Recapitalizing Our Infrastructure Countering Nuclear Terrorism About Our Programs Our History Who We Are Our Leadership Our Locations Budget Our Operations Library Bios Congressional Testimony Fact Sheets Newsletters Press Releases Photo Gallery Jobs Apply for Our

  15. The National Ignition Facility: Studying the Stars in the Laboratory

    SciTech Connect (OSTI)

    Boyd, R

    2008-09-17

    The National Ignition Facility, to be completed in 2009, will be the highest energy laser ever built. The high temperatures and densities it will produce will enable a number of experiments in inertial confinement fusion and stockpile stewardship, as well as in nuclear astrophysics, X-ray astronomy, hydrodynamics, and planetary science. The National Ignition Facility, NIF (1), located at Lawrence Livermore National Lab, (LLNL) is expected to produce inertial confinement fusion (ICF) by delivering sufficient laser energy to compress and heat a millimeter-radius pellet of DT sufficiently to produce fusion to {sup 4}He+neutron and 17.6 MeV per reaction. NIF will be completed by March, 2009, at which time a National Ignition Campaign (2), NIC, a series of experiments to optimize the ICF parameters, will begin. Although NIF is a research facility, a successful NIC would have implications for future energy sources. In addition to the goal of ICF, NIF will support programs in stockpile stewardship. However, the conditions that NIF creates will simulate those inside stars and planets sufficiently closely to provide compelling motivation for experiments in basic high-energy-density (HED) science especially, for the first time, in nuclear astrophysics.

  16. Electrically heated particulate filter enhanced ignition strategy

    DOE Patents [OSTI]

    Gonze, Eugene V; Paratore, Jr., Michael J

    2012-10-23

    An exhaust system that processes exhaust generated by an engine is provided. The system generally includes a particulate filter (PF) that filters particulates from the exhaust wherein an upstream end of the PF receives exhaust from the engine. A grid of electrically resistive material is applied to an exterior upstream surface of the PF and selectively heats exhaust passing through the grid to initiate combustion of particulates within the PF. A catalyst coating applied to at least one of the PF and the grid. A control module estimates a temperature of the grid and controls the engine to produce a desired exhaust product to increase the temperature of the grid.

  17. Nonpremixed ignition, laminar flame propagation, and mechanism reduction of n-butanol, iso-butanol, and methyl butanoate

    SciTech Connect (OSTI)

    Lu, Wei; Kelley, A. P.; Law, C. K.

    2011-01-01

    The non-premixed ignition temperature of n-butanol (CH{sub 3}CH{sub 2}CH{sub 2}CH{sub 2}OH), iso-butanol ((CH{sub 3}){sub 2}CHCH{sub 2}OH) and methyl butanoate (CH{sub 3}CH{sub 2}CH{sub 2}COOCH{sub 3}) was measured in a liquid pool assembly by heated oxidizer in a stagnation flow for system pressures of 1 and 3 atm. In addition, the stretch-corrected laminar flame speeds of mixtures of airn-butanol/iso-butanol/methyl butanoate were determined from the outwardly propagating spherical flame at initial pressures of up to 2 atm, for an extensive range of equivalence ratio. The ignition temperature and laminar flame speeds of n-butanol and methyl butanoate were computationally simulated with three recently developed kinetic mechanisms in the literature. Dominant reaction pathways to ignition and flame propagation were identified and discussed through a chemical explosive mode analysis (CEMA) and sensitivity analysis. The detailed models were further reduced through a series of systematic strategies. The reduced mechanisms provided excellent agreement in both homogeneous and diffusive combustion environments and greatly improved the computation efficiency.

  18. Effect of reinforcement phase on the mechanical property of tungsten nanocomposite synthesized by spark plasma sintering

    SciTech Connect (OSTI)

    Lee, Jin -Kyu; Kim, Song -Yi; Ott, Ryan T.; Kim, Jin -Young; Eckert, Jrgen; Lee, Min -Ha

    2015-07-15

    Nanostructured tungsten composites were fabricated by spark plasma sintering of nanostructured composite powders. The composite powders, which were synthesized by mechanical milling of tungsten and Ni-based alloy powders, are comprised of alternating layers of tungsten and metallic glass several hundred nanometers in size. The mechanical behavior of the nanostructured W composite is similar to pure tungsten, however, in contrast to monolithic pure tungsten, some macroscopic compressive plasticity accompanies the enhanced maximum strength up to 2.4 GPa by introducing reinforcement. As a result, we have found that the mechanical properties of the composites strongly depend on the uniformity of the nano-grained tungsten matrix and reinforcement phase distribution.

  19. A geophysical shock and air blast simulator at the National Ignition...

    Office of Scientific and Technical Information (OSTI)

    The energy partitioning energy coupling experiments at the National Ignition Facility (NIF) have been designed to measure simultaneously the coupling of energy from a...

  20. Numerical routines for predicting ignition in pyrotechnic devices

    SciTech Connect (OSTI)

    Pierce, K.G.

    1986-06-01

    Two numerical models of the thermal processes leading to ignition in a pyrotechnic device have been developed. These models are based on finite difference approximations to the heat diffusion equation, with temperature-dependent thermal properties, in a single spatial coordinate. The derivation of the finite difference equations is discussed and the methods employed at boundaries and interfaces are given. The sources of the thermal-properties data are identified and how these data are used is explained. The program structure is explained and example runs of the programs are given.

  1. Lawrence Livermore National Laboratory is home to the National Ignition

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    is home to the National Ignition Facility (NIF), which began full operations in March 2009. NIF's 192 powerful laser beams, housed in a 10-story building the size of 3 football fields, can deliver nearly 2 million joules of ultraviolet laser energy in billionth-of-a- second pulses to the target chamber center. When NIF's laser beams focus all of their energy on a target the size of a pencil eraser, they briefly produce extraordinary temperature and pressure conditions within the target. The

  2. Ethane ignition and oxidation behind reflected shock waves

    SciTech Connect (OSTI)

    de Vries, Jaap; Hall, Joel M.; Simmons, Stefanie L.; Kalitan, Danielle M.; Petersen, Eric L.; Rickard, Matthew J.A.

    2007-07-15

    Several diluted C{sub 2}H{sub 6}/O{sub 2}/Ar mixtures of varying concentrations and equivalence ratios (0.5<{phi}<2.0) were studied at temperatures between 1218 and 1860 K and at pressures between 0.57 and 3.0 atm using a shock tube. The argon dilution ranged from 91 to 98% by volume. Reaction progress was monitored using chemiluminescence emission from OH{sup *} and CH{sup *} at 307 and 431 nm, respectively. The dependence of ignition delay time on temperature, activation energy, and reactant concentrations is given in a master correlation of all the experimental data. The overall activation energy was found to be 39.6 kcal/mol over the range of conditions studied. For the first time in a shock-tube C{sub 2}H{sub 6} oxidation study, detailed species profile data and quantitative OH{sup *} time histories were documented, in addition to ignition delay times, and compared against modern detailed mechanisms. Because of the comprehensive scope of the present study and the high precision of the experimental data, several conclusions can be drawn that could not have been reached from earlier studies. Although there is some discrepancy among previous ethane oxidation data, the present work clearly shows the convergence of ignition delay time measurements to those herein and the remarkable accuracy of current kinetics models over most of the parameter space explored, despite the variation in the literature data. However, two areas shown to still need more measurements and better modeling are those of higher pressures and fuel-rich ethane-air mixtures. After appropriate OH{sup *} and CH{sup *} submechanisms are added, two modern chemical kinetics mechanisms containing high-temperature ethane chemistry are compared to the data to gauge the current state of C{sub 2}H{sub 6} oxidation modeling over the conditions of this study. The reproduction of the OH{sup *} and CH{sup *} profiles, together with {tau}{sub ign} predictions by these models, are compared against the profiles and ignition times found in the experimental data. The models are then used to identify some key reactions in ethane oxidation and CH formation under the conditions of this study. (author)

  3. The First Experiments on the National Ignition Facility

    SciTech Connect (OSTI)

    Landen, O L; Glenzer, S; Froula, D; Dewald, E; Suter, L J; Schneider, M; Hinkel, D; Fernandez, J; Kline, J; Goldman, S; Braun, D; Celliers, P; Moon, S; Robey, H; Lanier, N; Glendinning, G; Blue, B; Wilde, B; Jones, O; Schein, J; Divol, L; Kalantar, D; Campbell, K; Holder, J; MacDonald, J; Niemann, C; Mackinnon, A; Collins, R; Bradley, D; Eggert, J; Hicks, D; Gregori, G; Kirkwood, R; Young, B; Foster, J; Hansen, F; Perry, T; Munro, D; Baldis, H; Grim, G; Heeter, R; Hegelich, B; Montgomery, D; Rochau, G; Olson, R; Turner, R; Workman, J; Berger, R; Cohen, B; Kruer, W; Langdon, B; Langer, S; Meezan, N; Rose, H; Still, B; Williams, E; Dodd, E; Edwards, J; Monteil, M; Stevenson, M; Thomas, B; Coker, R; Magelssen, G; Rosen, P; Stry, P; Woods, D; Weber, S; Alvarez, S; Armstrong, G; Bahr, R; Bourgade, J; Bower, D; Celeste, J; Chrisp, M; Compton, S; Cox, J; Constantin, C; Costa, R; Duncan, J; Ellis, A; Emig, J; Gautier, C; Greenwood, A; Griffith, R; Holdner, F; Holtmeier, G; Hargrove, D; James, T; Kamperschroer, J; Kimbrough, J; Landon, M; Lee, D; Malone, R; May, M; Montelongo, S; Moody, J; Ng, E; Nikitin, A; Pellinen, D; Piston, K; Poole, M; Rekow, V; Rhodes, M; Shepherd, R; Shiromizu, S; Voloshin, D; Warrick, A; Watts, P; Weber, F; Young, P; Arnold, P; Atherton, L J; Bardsley, G; Bonanno, R; Borger, T; Bowers, M; Bryant, R; Buckman, S; Burkhart, S; Cooper, F; Dixit, S; Erbert, G; Eder, D; Ehrlich, B; Felker, B; Fornes, J; Frieders, G; Gardner, S; Gates, C; Gonzalez, M; Grace, S; Hall, T; Haynam, C; Heestand, G; Henesian, M; Hermann, M; Hermes, G; Huber, S; Jancaitis, K; Johnson, S; Kauffman, B; Kelleher, T; Kohut, T; Koniges, A E; Labiak, T; Latray, D; Lee, A; Lund, D; Mahavandi, S; Manes, K R; Marshall, C; McBride, J; McCarville, T; McGrew, L; Menapace, J; Mertens, E; Munro, D; Murray, J; Neumann, J; Newton, M; Opsahl, P; Padilla, E; Parham, T; Parrish, G; Petty, C; Polk, M; Powell, C; Reinbachs, I; Rinnert, R; Riordan, B; Ross, G; Robert, V; Tobin, M; Sailors, S; Saunders, R; Schmitt, M; Shaw, M; Singh, M; Spaeth, M; Stephens, A; Tietbohl, G; Tuck, J; Van Wonterghem, B; Vidal, R; Wegner, P; Whitman, P; Williams, K; Winward, K; Work, K

    2005-11-11

    A first set of laser-plasma interaction, hohlraum energetics and hydrodynamic experiments have been performed using the first 4 beams of the National Ignition Facility (NIF), in support of indirect drive Inertial Confinement Fusion (ICF) and High Energy Density Physics (HEDP). In parallel, a robust set of optical and x-ray spectrometers, interferometer, calorimeters and imagers have been activated. The experiments have been undertaken with laser powers and energies of up to 8 TW and 17 kJ in flattop and shaped 1-9 ns pulses focused with various beam smoothing options.

  4. Gas-filled hohlraum experiments at the national ignition facility.

    SciTech Connect (OSTI)

    Fernndez, J. C.; Gautier, D. C.; Goldman, S. R.; Grimm, B. M.; Hegelich, B. M.; Kline, J. L.; Montgomery, D. S.; Lanier, N. E.; Rose, H. A.; Schmidt, D. M.; Swift, D. C.; Workman, J. B.; Alvarez, Sharon; Bower, Dan.; Braun, Dave.; Campbell, K.; DeWald, E.; Glenzer, S.; Holder, J.; Kamperschroer, J. H.; Kimbrough, Joe; Kirkwood, Robert; Landen, O. L.; Mccarville, Tom; Macgowan, B.; Mackinnon, A.; Niemann, C.; Schein, J.; Schneider, M; Watts, Phil; Young, Ben-li 194154; Young B.

    2004-01-01

    The summary of this paper is: (1) We have fielded on NIF a gas-filled hohlraum designed for future ignition experiments; (2) Wall-motion measurements are consistent with LASNEX simulations; (3) LPI back-scattering results have confounded expectations - (a) Stimulated Brillouin (SBS) dominates Raman (SRS) for any gas-fill species, (b) Measured SBS time-averaged reflectivity values are high, peak values are even higher, (c) SRS and SBS peak while laser-pulse is rising; and (4) Plasma conditions at the onset of high back-scattering yield high SBS convective linear gain - Wavelengths of the back-scattered light is predicted by linear theory.

  5. ENERGY PARTITIONING, ENERGY COUPLING (EPEC) EXPERIMENTS AT THE NATIONAL IGNITION FACILITY

    SciTech Connect (OSTI)

    Fournier, K B; Brown, C G; May, M J; Dunlop, W H; Compton, S M; Kane, J O; Mirkarimi, P B; Guyton, R L; Huffman, E

    2012-01-05

    The energy-partitioning, energy-coupling (EPEC) experiments at the National Ignition Facility (NIF) will simultaneously measure the coupling of energy into both ground shock and air-blast overpressure from a laser-driven target. The source target for the experiment is positioned at a known height above the ground-surface simulant and is heated by four beams from NIF. The resulting target energy density and specific energy are equal to those of a low-yield nuclear device. The ground-shock stress waves and atmospheric overpressure waveforms that result in our test system are hydrodynamically scaled analogs of seismic and air-blast phenomena caused by a nuclear weapon. In what follows, we discuss the motivation for our investigation and briefly describe NIF. Then, we introduce the EPEC experiments, including diagnostics, in more detail.

  6. Wildfire ignition resistant home design(WIRHD) program: Full-scale testing and demonstration final report.

    SciTech Connect (OSTI)

    Quarles, Stephen, L.; Sindelar, Melissa

    2011-12-13

    The primary goal of the Wildfire ignition resistant home design(WIRHD) program was to develop a home evaluation tool that could assess the ignition potential of a structure subjected to wildfire exposures. This report describes the tests that were conducted, summarizes the results, and discusses the implications of these results with regard to the vulnerabilities to homes and buildings.

  7. Progress in Fast Ignition Studies with Electrons and Protons

    SciTech Connect (OSTI)

    MacKinnon, A. J.; Chen, H.; Hey, D.; Key, M. H.; MacPhee, A. G.; Patel, P. K.; Ping, Y.; Akli, K. U.; Stephens, R. B.; Bartal, T.; Beg, F. N.; Chawla, S.; Chen, S.; Higginson, D.; King, J. A.; Ma, T.; Wei, M. S.; Chen, C. D.; Chowdhury, E.; Link, A.

    2009-09-10

    Isochoric heating of inertially confined fusion plasmas by laser driven MeV electrons or protons is an area of great topical interest in the inertial confinement fusion community, particularly with respect to the fast ignition (FI) concept for initiating burn in a fusion capsule. In order to investigate critical aspects needed for a FI point design, experiments were performed to study 1) laser-to-electrons or protons conversion issues and 2) laser-cone interactions including prepulse effects. A large suite of diagnostics was utilized to study these important parameters. Using cone--wire surrogate targets it is found that pre-pulse levels on medium scale lasers such as Titan at Lawrence Livermore National Laboratory produce long scale length plasmas that strongly effect coupling of the laser to FI relevant electrons inside cones. The cone wall thickness also affects coupling to the wire. Conversion efficiency to protons has also been measured and modeled as a function of target thickness, material. Conclusions from the proton and electron source experiments will be presented. Recent advances in modeling electron transport and innovative target designs for reducing igniter energy and increasing gain curves will also be discussed. In conclusion, a program of study will be presented based on understanding the fundamental physics of the electron or proton source relevant to FI.

  8. Finite Mach number spherical shock wave, application to shock ignition

    SciTech Connect (OSTI)

    Vallet, A.; Ribeyre, X.; Tikhonchuk, V.

    2013-08-15

    A converging and diverging spherical shock wave with a finite initial Mach number M{sub s0} is described by using a perturbative approach over a small parameter M{sub s}{sup ?2}. The zeroth order solution is the Guderley's self-similar solution. The first order correction to this solution accounts for the effects of the shock strength. Whereas it was constant in the Guderley's asymptotic solution, the amplification factor of the finite amplitude shock ?(t)?dU{sub s}/dR{sub s} now varies in time. The coefficients present in its series form are iteratively calculated so that the solution does not undergo any singular behavior apart from the position of the shock. The analytical form of the corrected solution in the vicinity of singular points provides a better physical understanding of the finite shock Mach number effects. The correction affects mainly the flow density and the pressure after the shock rebound. In application to the shock ignition scheme, it is shown that the ignition criterion is modified by more than 20% if the fuel pressure prior to the final shock is taken into account. A good agreement is obtained with hydrodynamic simulations using a Lagrangian code.

  9. Ignition and extinction phenomena in helium micro hollow cathode discharges

    SciTech Connect (OSTI)

    Kulsreshath, M. K.; Schwaederle, L.; Dufour, T.; Lefaucheux, P.; Dussart, R.; Overzet, L. J.

    2013-12-28

    Micro hollow cathode discharges (MHCD) were produced using 250??m thick dielectric layer of alumina sandwiched between two nickel electrodes of 8??m thickness. A through cavity at the center of the chip was formed by laser drilling technique. MHCD with a diameter of few hundreds of micrometers allowed us to generate direct current discharges in helium at up to atmospheric pressure. A slowly varying ramped voltage generator was used to study the ignition and the extinction periods of the microdischarges. The analysis was performed by using electrical characterisation of the V-I behaviour and the measurement of He*({sup 3}S{sub 1}) metastable atoms density by tunable diode laser spectroscopy. At the ignition of the microdischarges, 2??s long current peak as high as 24?mA was observed, sometimes followed by low amplitude damped oscillations. At helium pressure above 400?Torr, an oscillatory behaviour of the discharge current was observed just before the extinction of the microdischarges. The same type of instability in the extinction period at high pressure also appeared on the density of He*({sup 3}S{sub 1}) metastable atoms, but delayed by a few ?s relative to the current oscillations. Metastable atoms thus cannot be at the origin of the generation of the observed instabilities.

  10. Direct Injection Compression Ignition Diesel Automotive Technology Education GATE Program

    SciTech Connect (OSTI)

    Anderson, Carl L

    2006-09-25

    The underlying goal of this prqject was to provide multi-disciplinary engineering training for graduate students in the area of internal combustion engines, specifically in direct injection compression ignition engines. The program was designed to educate highly qualified engineers and scientists that will seek to overcome teclmological barriers preventing the development and production of cost-effective high-efficiency vehicles for the U.S. market. Fu1iher, these highly qualified engineers and scientists will foster an educational process to train a future workforce of automotive engineering professionals who are knowledgeable about and have experience in developing and commercializing critical advanced automotive teclmologies. Eight objectives were defmed to accomplish this goal: 1. Develop an interdisciplinary internal co1nbustion engine curriculum emphasizing direct injected combustion ignited diesel engines. 2. Encourage and promote interdisciplinary interaction of the faculty. 3. Offer a Ph.D. degree in internal combustion engines based upon an interdisciplinary cuniculum. 4. Promote strong interaction with indusuy, develop a sense of responsibility with industry and pursue a self sustaining program. 5. Establish collaborative arrangements and network universities active in internal combustion engine study. 6. Further Enhance a First Class educational facility. 7. Establish 'off-campus' M.S. and Ph.D. engine programs of study at various indusuial sites. 8. Extend and Enhance the Graduate Experience.

  11. Effect of reinforcement phase on the mechanical property of tungsten nanocomposite synthesized by spark plasma sintering

    DOE Public Access Gateway for Energy & Science Beta (PAGES Beta)

    Lee, Jin -Kyu; Kim, Song -Yi; Ott, Ryan T.; Kim, Jin -Young; Eckert, Jürgen; TU Dresden, Dresden; Lee, Min -Ha

    2015-07-15

    Nanostructured tungsten composites were fabricated by spark plasma sintering of nanostructured composite powders. The composite powders, which were synthesized by mechanical milling of tungsten and Ni-based alloy powders, are comprised of alternating layers of tungsten and metallic glass several hundred nanometers in size. The mechanical behavior of the nanostructured W composite is similar to pure tungsten, however, in contrast to monolithic pure tungsten, some macroscopic compressive plasticity accompanies the enhanced maximum strength up to 2.4 GPa by introducing reinforcement. As a result, we have found that the mechanical properties of the composites strongly depend on the uniformity of the nano-grainedmore » tungsten matrix and reinforcement phase distribution.« less

  12. Spark-induced radiation from hydrogen or deuterium-loaded palladium

    SciTech Connect (OSTI)

    Klema, E.D.; Iseler, G.W.

    1996-09-01

    Three sets of experiments were conducted to investigate the radiation produced by spark discharge on (a) oxidized palladium samples, (b) oxidized palladium samples loaded with hydrogen, and (c) oxidized palladium samples loaded with deuterium. In the first set, no radiation was measured above background; in the second set, 24-keV X rays were observed, and in the third set, 17-keV X rays were produced. The intensities of the hydrogen X rays were measured over a period of 12 days. During this time, the daily fluctuations overshadowed any long-term variation that might be present. The deuterium X rays were followed over a period of 26 weeks. Again, the intensities fluctuated with time, obscuring the long-term trend; in one case, there was a 40% change from one day to the next. 3 refs.

  13. Investigation of a rotary valving system with variable valve timing for internal combustion engines: Final technical report

    SciTech Connect (OSTI)

    Cross, P.C.; Hansen, C.N.

    1994-11-18

    The objective of the program was to provide a functional demonstration of the Hansen Rotary Valving System with Variable Valve timing (HRVS/VVT), capable of throttleless inlet charge control, as an alternative to conventional poppet-valves for use in spark ignited internal combustion engines. The goal of this new technology is to secure benefits in fuel economy, broadened torque band, vibration reduction, and overhaul accessibility. Additionally, use of the variable valve timing capability to vary the effective compression ratio is expected to improve multi-fuel tolerance and efficiency. Efforts directed at the design of HRVS components proved to be far more extensive than had been anticipated, ultimately requiring that proof-trial design/development work be performed. Although both time and funds were exhausted before optical or ion-probe types of in-cylinder investigation could be undertaken, a great deal of laboratory data was acquired during the course of the design/development work. This laboratory data is the basis for the information presented in this Final Report.

  14. Shock-ignition relevant experiments with planar targets on OMEGA

    SciTech Connect (OSTI)

    Hohenberger, M.; Hu, S. X.; Anderson, K. S.; Boehly, T. R.; Sangster, T. C.; Seka, W.; Stoeckl, C.; Yaakobi, B.; Theobald, W.; Lafon, M.; Nora, R.; Fusion Science Center, University of Rochester, Rochester, New York 14623 ; Betti, R.; Meyerhofer, D. D.; Fusion Science Center, University of Rochester, Rochester, New York 14623; Departments of Mechanical Engineering and Physics, University of Rochester, Rochester, New York 14627 ; Casner, A.; Fratanduono, D. E.; Ribeyre, X.; Schurtz, G.

    2014-02-15

    We report on laser-driven, strong-shock generation and hot-electron production in planar targets in the presence of a pre-plasma at shock-ignition (SI) relevant laser and pre-plasma conditions. 2-D simulations reproduce the shock dynamics well, indicating ablator shocks of up to 75 Mbar have been generated. We observe hot-electron temperatures of ?70?keV at intensities of 1.4??10{sup 15}?W/cm{sup 2} with multiple overlapping beams driving the two-plasmon decay instability. When extrapolated to SI-relevant intensities of ?10{sup 16}?W/cm{sup 2}, the hot electron temperature will likely exceed 100?keV, suggesting that tightly focused beams without overlap are better suited for launching the ignitor shock.

  15. A simplified model of TiH1.65/KClO4 pyrotechnic ignition.

    SciTech Connect (OSTI)

    Chen, Ken Shuang

    2009-04-01

    A simplified model was developed and is presented in this report for simulating thermal transport coupled with chemical reactions that lead to the pyrotechnic ignition of TiH1.65/KClO4 powder. The model takes into account Joule heating via a bridgewire, thermal contact resistance at the wire/powder interface, convective heat loss to the surroundings, and heat released from the TiH1.65- and KClO4-decomposition and TiO2-oxidation reactions. Chemical kinetic sub-models were put forth to describe the chemical reaction rate(s) and quantify the resultant heat release. The simplified model predicts pyrotechnic ignition when heat from the pyrotechnic reactions is accounted for. Effects of six key parameters on ignition were examined. It was found that the two reaction-rate parameters and the thermal contact resistance significantly affect the dynamic ignition process whereas the convective heat transfer coefficient essentially has no effect on the ignition time. Effects of the initial/ambient temperature and electrical current load through the wire are as expected. Ignition time increases as the initial/ambient temperature is lowered or the wire current load is reduced. Lastly, critical needs such as experiments to determine reaction-rate and other model-input parameters and to measure temperature profiles, time to ignition and burn-rate data for model validation as well as efforts in incorporating reaction-rate dependency on pressure are pointed out.

  16. Polar-direct-drive experiments on the National Ignition Facility

    DOE Public Access Gateway for Energy & Science Beta (PAGES Beta)

    Hohenberger, M.; Radha, P. B.; Myatt, J. F.; LePape, S.; Marozas, J. A.; Marshall, F. J.; Michel, D. T.; Regan, S. P.; Seka, W.; Shvydky, A.; et al

    2015-05-11

    To support direct-drive inertial confinement fusion experiments at the National Ignition Facility (NIF) [G. H. Miller, E. I. Moses, and C. R. Wuest, Opt. Eng. 43, 2841 (2004)] in its indirect-drive beam configuration, the polar-direct-drive (PDD) concept [S. Skupsky et al., Phys. Plasmas 11, 2763 (2004)] has been proposed. Ignition in PDD geometry requires direct-drive–specific beam smoothing, phase plates, and repointing the NIF beams toward the equator to ensure symmetric target irradiation. First experiments to study the energetics and preheat in PDD implosions at the NIF have been performed. These experiments utilize the NIF in its current configuration, including beammore » geometry, phase plates, and beam smoothing. Room-temperature, 2.2-mm-diam plastic shells filled with D₂ gas were imploded with total drive energies ranging from ~500 to 750 kJ with peak powers of 120 to 180 TW and peak on-target irradiances at the initial target radius from 8 10¹⁴ to 1.2 10¹⁵W/cm². Results from these initial experiments are presented, including measurements of shell trajectory, implosion symmetry, and the level of hot-electron preheat in plastic and Si ablators. Experiments are simulated with the 2-D hydrodynamics code DRACO including a full 3-D ray-trace to model oblique beams, and models for nonlocal electron transport and cross-beam energy transport (CBET). These simulations indicate that CBET affects the shell symmetry and leads to a loss of energy imparted onto the shell, consistent with the experimental data.« less

  17. Polar-direct-drive experiments on the National Ignition Facility

    SciTech Connect (OSTI)

    Hohenberger, M.; Radha, P. B.; Myatt, J. F.; Marozas, J. A.; Marshall, F. J.; Michel, D. T.; Regan, S. P.; Seka, W.; Shvydky, A.; Sangster, T. C.; Betti, R.; Boehly, T. R.; Bonino, M. J.; Collins, T. J. B.; Craxton, R. S.; Delettrez, J. A.; Edgell, D. H.; Epstein, R.; Fiksel, G.; Froula, D. H.; and others

    2015-05-15

    To support direct-drive inertial confinement fusion experiments at the National Ignition Facility (NIF) [G. H. Miller, E. I. Moses, and C. R. Wuest, Opt. Eng. 43, 2841 (2004)] in its indirect-drive beam configuration, the polar-direct-drive (PDD) concept [S. Skupsky et al., Phys. Plasmas 11, 2763 (2004)] has been proposed. Ignition in PDD geometry requires direct-drivespecific beam smoothing, phase plates, and repointing the NIF beams toward the equator to ensure symmetric target irradiation. First experiments to study the energetics and preheat in PDD implosions at the NIF have been performed. These experiments utilize the NIF in its current configuration, including beam geometry, phase plates, and beam smoothing. Room-temperature, 2.2-mm-diam plastic shells filled with D{sub 2} gas were imploded with total drive energies ranging from ?500 to 750?kJ with peak powers of 120 to 180 TW and peak on-target irradiances at the initial target radius from 8??10{sup 14} to 1.2??10{sup 15?}W/cm{sup 2}. Results from these initial experiments are presented, including measurements of shell trajectory, implosion symmetry, and the level of hot-electron preheat in plastic and Si ablators. Experiments are simulated with the 2-D hydrodynamics code DRACO including a full 3-D ray-trace to model oblique beams, and models for nonlocal electron transport and cross-beam energy transport (CBET). These simulations indicate that CBET affects the shell symmetry and leads to a loss of energy imparted onto the shell, consistent with the experimental data.

  18. Fuel Effects on Ignition and Their Impact on Advanced Combustion Engines (Poster)

    SciTech Connect (OSTI)

    Taylor, J.; Li, H.; Neill, S.

    2006-08-01

    The objective of this report is to develop a pathway to use easily measured ignition properties as metrics for characterizing fuels in advanced combustion engine research--correlate IQT{trademark} measured parameters with engine data. In HCCL engines, ignition timing depends on the reaction rates throughout compression stroke: need to understand sensitivity to T, P, and [O{sub 2}]; need to rank fuels based on more than one set of conditions; and need to understand how fuel composition (molecular species) affect ignition properties.

  19. Ion beam requirements for fast ignition of inertial fusion targets (Journal

    Office of Scientific and Technical Information (OSTI)

    Article) | SciTech Connect Ion beam requirements for fast ignition of inertial fusion targets Citation Details In-Document Search Title: Ion beam requirements for fast ignition of inertial fusion targets Ion beam requirements for fast ignition are investigated by numerical simulation taking into account new effects, such as ion beam divergence, not included before. We assume that ions are generated by the TNSA scheme in a curved foil placed inside a re-entrant cone and focused on the cone

  20. A low cost igniter utilizing an SCB and titanium sub-hydride potassium perchlorate pyrotechnic

    SciTech Connect (OSTI)

    Bickes, R.W. Jr.; Grubelich, M.C.; Hartman, J.K.; McCampbell, C.B.; Churchill, J.K.

    1993-12-31

    A conventional NSI (NASA standard initiator) normally employs a hot-wire ignition element to ignite ZPP (zirconium potassium perchlorate). With minor modifications to the interior of a header similar to an NSI device to accommodate an SCB (semiconductor bridge), a low cost initiator was obtained. In addition, the ZPP was replaced with THKP (titanium subhydride potassium perchlorate) to obtain increased overall gas production and reduced static-charge sensitivity. This paper reports on the all-fire and no-fire levels obtained and on a dual mix device that uses THKP as the igniter mix and a thermite as the output mix.

  1. Advanced Concept Exploration for Fast Ignition Science Program, Final Report

    SciTech Connect (OSTI)

    Stephens, Richard Burnite; McLean, Harry M.; Theobald, Wolfgang; Akli, Kramer U.; Beg, Farhat N.; Sentoku, Yasuhiko; Schumacher, Douglass W.; Wei, Mingsheng

    2013-09-04

    The Fast Ignition (FI) Concept for Inertial Confinement Fusion (ICF) has the potential to provide a significant advance in the technical attractiveness of Inertial Fusion Energy reactors. FI differs from conventional central hot spot (CHS) target ignition by decoupling compression from heating: using a laser (or heavy ion beam or Z pinch) drive pulse (10s of nanoseconds) to create a dense fuel and a second, much shorter (~10 picoseconds) high intensity pulse to ignite a small volume within the dense fuel. The physics of fast ignition process was the focus of our Advanced Concept Exploration (ACE) program. Ignition depends critically on two major issues involving Relativistic High Energy Density (RHED) physics: The laser-induced creation of fast electrons and their propagation in high-density plasmas. Our program has developed new experimental platforms, diagnostic packages, computer modeling analyses, and taken advantage of the increasing energy available at laser facilities to advance understanding of the fundamental physics underlying these issues. Our program had three thrust areas: Understand the production and characteristics of fast electrons resulting from FI relevant laser-plasma interactions and their dependence on laser prepulse and laser pulse length. Investigate the subsequent fast electron transport in solid and through hot (FI-relevant) plasmas. Conduct and understand integrated core-heating experiments by comparison to simulations. Over the whole period of this project (three years for this contract), we have greatly advanced our fundamental understanding of the underlying properties in all three areas: Comprehensive studies on fast electron source characteristics have shown that they are controlled by the laser intensity distribution and the topology and plasma density gradient. Laser pre-pulse induced pre-plasma in front of a solid surface results in increased stand-off distances from the electron origin to the high density target as well as large and erratic spread of the electron beam with increasing short pulse duration. We have demonstrated, using newly available higher contrast lasers, an improved energy coupling, painting a promising picture for FI feasibility. Our detailed experiments and analyses of fast electron transport dependence on target material have shown that it is feasible to collimate fast electron beam by self-generated resistive magnetic fields in engineered targets with a rather simple geometry. Stable and collimated electron beam with spot size as small as 50-?m after >100-?m propagation distance (an angular divergence angle of 20!) in solid density plasma targets has been demonstrated with FI-relevant (10-ps, >1-kJ) laser pulses Such collimated beam would meet the required heating beam size for FI. Our new experimental platforms developed for the OMEGA laser (i.e., i) high resolution 8 keV backlighter platform for cone-in-shell implosion and ii) the 8 keV imaging with Cu-doped shell targets for detailed transport characterization) have enabled us to experimentally confirm fuel assembly from cone-in-shell implosion with record-high areal density. We have also made the first direct measurement of fast electron transport and spatial energy deposition in integrated FI experiments enabling the first experiment-based benchmarking of integrated simulation codes. Executing this program required a large team. It was managed as a collaboration between General Atomics (GA), Lawrence Livermore National Laboratory (LLNL), and the Laboratory for Laser Energetics (LLE). GA fulfills its responsibilities jointly with the University of California, San Diego (UCSD), The Ohio State University (OSU) and the University of Nevada at Reno (UNR). The division of responsibility was as follows: (1) LLE had primary leadership for channeling studies and the integrated energy transfer, (2) LLNL led the development of measurement methods, analysis, and deployment of diagnostics, and (3) GA together with UCSD, OSU and UNR studied the detailed energy-transfer physics. The experimental program was carried out using the Titan laser at the Jupiter Laser Facility at LLNL, the OMEGA and OMEGA EP lasers at LLE and the Texas Petawatt laser at the University of Texas, Austin. Modeling has been pursued on large computing facilities at LLNL, OSU, and UCSD using codes developed (by us and others) within the HEDLP program, commercial codes, and by leveraging existing simulations codes developed by the National Nuclear Security Administration ICF program. One important aspect of this program was the involvement and training of young scientists including postdoctoral fellows and graduate students. This project generated an impressive forty articles in high quality journals including nine (two under review) in Physical Review Letters during the three years of this grant and five graduate students completed their doctoral dissertations.

  2. Knock-free engine control system for turbocharged automotive engine

    SciTech Connect (OSTI)

    Hirabayashi, Y.

    1985-04-09

    In a turbocharged internal combustion engine, in order to optimize engine torque output spark timing control and boost pressure control are coordinated in such a manner that spark advance angle is adjusted only when the measured boost pressure equals a predetermined value and is allowed to vary only within a specified range advanced from a reference value derived from an empirical memory table on the basis of engine speed and boost pressure. When engine operating conditions are such that spark advance angle would fall outside of the specified range, spark advance angle is then held at the empirical value and boost pressure is adjusted in order to optimize engine torque. The coordinated control system can also be designed to respond to exhaust gas temperature on a first-priority basis, i.e., when exhaust temperature is sensed to be dangerously high, boost pressure is reduced regardless of other engine conditions.

  3. Method and apparatus for igniting an in situ oil shale retort

    DOE Patents [OSTI]

    Burton, Robert S. (Grand Junction, CO); Rundberg, Sten I. (Debeque, CO); Vaughn, James V. (Debeque, CO); Williams, Thomas P. (Debeque, CO); Benson, Gregory C. (Grand Junction, CO)

    1981-01-01

    A technique is provided for igniting an in situ oil shale retort having an open void space over the top of a fragmented mass of particles in the retort. A conduit is extended into the void space through a hole in overlying unfragmented formation and has an open end above the top surface of the fragmented mass. A primary air pipe having an open end above the open end of the conduit and a liquid atomizing fuel nozzle in the primary air pipe above the open end of the primary air pipe are centered in the conduit. Fuel is introduced through the nozzle, primary air through the pipe, and secondary air is introduced through the conduit for vortical flow past the open end of the primary air pipe. The resultant fuel and air mixture is ignited for combustion within the conduit and the resultant heated ignition gas impinges on the fragmented mass for heating oil shale to an ignition temperature.

  4. Effect of ignition conditions on upward flame spread on a composite material in a corner configuration

    SciTech Connect (OSTI)

    Ohlemiller, T.; Cleary, T.; Shields, J.

    1996-12-31

    This paper focuses on the issue of fire growth on composite materials beyond the region immediately subjected to an ignition source. Suppression of this growth is one of the key issues in realizing the safe usage of composite structural materials. A vinyl ester/glass composite was tested in the form of a 90{degrees} comer configuration with an inert ceiling segment 2.44 m above the top of the fire source. The igniter was a propane burner, either 23 or 38 cm in width with power output varied from 30 to 150 Kw. Upward flame spread rate and heat release rate were measured mainly for a brominated vinyl ester resin but limited results were also obtained for a non-flame retarded vinyl ester and a similar composite coated with an intumescent paint. Rapid fire growth beyond the igniter region was seen for the largest igniter power case; the intumescent coating successfully prevented fire growth for this case.

  5. X-ray area backlighter development at the National Ignition Facility...

    Office of Scientific and Technical Information (OSTI)

    the National Ignition Facility (invited) 1D spectral imaging was used to characterize the K-shell emission of Z 30-35 and Z 40-42 laser-irradiated foils at the National...

  6. Qualitative assessment of the ignition of highly flammable fuels by primary explosives

    SciTech Connect (OSTI)

    Elischer, P.P.; De Yong, L.

    1983-06-01

    An assessment of the ignition of fuel/air mixtures and of fabrics soaked with different fuels (ethanol, n-hexane and diethyl ether) by primary explosives has been carried out.

  7. X-ray area backlighter development at the National Ignition Facility...

    Office of Scientific and Technical Information (OSTI)

    Journal Article: X-ray area backlighter development at the National Ignition Facility (NIF) Citation Details In-Document Search Title: X-ray area backlighter development at the...

  8. Tungsten bridge for the low energy ignition of explosive and energetic materials

    DOE Patents [OSTI]

    Benson, David A. (Albuquerque, NM); Bickes, Jr., Robert W. (Albuquerque, NM); Blewer, Robert S. (Albuquerque, NM)

    1990-01-01

    A tungsten bridge device for the low energy ignition of explosive and energetic materials is disclosed. The device is fabricated on a silicon-on-sapphire substrate which has an insulating bridge element defined therein using standard integrated circuit fabrication techniques. Then, a thin layer of tungsten is selectively deposited on the silicon bridge layer using chemical vapor deposition techniques. Finally, conductive lands are deposited on each end of the tungsten bridge layer to form the device. It has been found that this device exhibits substantially shorter ignition times than standard metal bridges and foil igniting devices. In addition, substantially less energy is required to cause ignition of the tungsten bridge device of the present invention than is required for common metal bridges and foil devices used for the same purpose.

  9. Tungsten bridge for the low energy ignition of explosive and energetic materials

    DOE Patents [OSTI]

    Benson, D.A.; Bickes, R.W. Jr.; Blewer, R.S.

    1990-12-11

    A tungsten bridge device for the low energy ignition of explosive and energetic materials is disclosed. The device is fabricated on a silicon-on-sapphire substrate which has an insulating bridge element defined therein using standard integrated circuit fabrication techniques. Then, a thin layer of tungsten is selectively deposited on the silicon bridge layer using chemical vapor deposition techniques. Finally, conductive lands are deposited on each end of the tungsten bridge layer to form the device. It has been found that this device exhibits substantially shorter ignition times than standard metal bridges and foil igniting devices. In addition, substantially less energy is required to cause ignition of the tungsten bridge device of the present invention than is required for common metal bridges and foil devices used for the same purpose. 2 figs.

  10. Homogeneous Charge Compression Ignition (HCCI) R&D | Department of Energy

    Office of Energy Efficiency and Renewable Energy (EERE) Indexed Site

    Homogeneous Charge Compression Ignition (HCCI) R&D Homogeneous Charge Compression Ignition (HCCI) R&D 2002 DEER Conference Presentation: Lawrence Livermore National Laboratory PDF icon 2002_deer_aceves.pdf More Documents & Publications Detailed Modeling of HCCI and PCCI combustion and Multi-cylinder HCCI Engine Control Bridging the Gap between Fundamental Physics and Chemistry and Applied Models for HCCI Engines Modeling of HCCI and PCCI Combustion Processes

  11. "New Results from the National Ignition Facility", Dr. John Lindl, Lawrence

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Livermore National Laboratory | Princeton Plasma Physics Lab November 7, 2012, 4:15pm Colloquia MBG Auditorium "New Results from the National Ignition Facility", Dr. John Lindl, Lawrence Livermore National Laboratory Since completion of the NIF construction project in March 2009, a wide variety of diagnostics, facility infrastructure, and experimental platforms have been qualified. NIF reached its design goal of 1.8 MJ and 500 TW of ultraviolet light in 2012. The Ignition Campaign

  12. Utilizing the Rapid Ignition Region of HCCI to Attain > 60% BTE |

    Office of Energy Efficiency and Renewable Energy (EERE) Indexed Site

    Department of Energy Rapid Ignition Region of HCCI to Attain > 60% BTE Utilizing the Rapid Ignition Region of HCCI to Attain > 60% BTE HCCI is inherently able to produce such rapid combustion (10 … 100µs) that it is effectively constant volume combustion. Constant volume combustion offers significant opportunity for dramatically improving ICRE BTE. However, to be used with conventional ICRE slider-crank kinematics, HCCI must transformed to a moderated mode of combustion that is far

  13. Effect of Premixed Charge Compression Ignition on Vehicle Fuel Economy and

    Office of Energy Efficiency and Renewable Energy (EERE) Indexed Site

    Emissions Reduction over Transient Driving Cycles | Department of Energy Premixed Charge Compression Ignition on Vehicle Fuel Economy and Emissions Reduction over Transient Driving Cycles Effect of Premixed Charge Compression Ignition on Vehicle Fuel Economy and Emissions Reduction over Transient Driving Cycles In conventional vehicles, most engine operating points over a UDDS driving cycle stay within PCCI operation limits but PCCI in HEVs is limited because of higher loads and many

  14. Spherical strong-shock generation for shock-ignition inertial fusion

    Office of Scientific and Technical Information (OSTI)

    (Journal Article) | SciTech Connect Spherical strong-shock generation for shock-ignition inertial fusion Citation Details In-Document Search Title: Spherical strong-shock generation for shock-ignition inertial fusion Recent experiments on the Laboratory for Laser Energetics' OMEGA laser have been carried out to produce strong shocks in solid spherical targets with direct laser illumination. The shocks are launched at pressures of several hundred Mbars and reach Gbar upon convergence. The

  15. Ignition properties of n-butane and iso-butane in a rapid compression machine

    SciTech Connect (OSTI)

    Gersen, S.; Darmeveil, J.H.; Mokhov, A.V.; Levinsky, H.B.

    2010-02-15

    Autoignition delay times of n-butane and iso-butane have been measured in a Rapid Compression Machine in the temperature range 660-1010 K, at pressures varying from 14 to 36 bar and at equivalence ratios {phi} = 1.0 and {phi} = 0.5. Both butane isomers exhibit a negative-temperature-coefficient (NTC) region and, at low temperatures, two-stage ignition. At temperatures below {proportional_to}900 K, the delay times for iso-butane are longer than those for the normal isomer, while above this temperature both butanes give essentially the same results. At temperatures above {proportional_to}720 K the delay times of the lean mixtures are twice those for stoichiometric compositions; at T < 720 K, the equivalence ratio is seen to have little influence on the ignition behavior. Increasing the pressure from 15 bar to 30 bar decreases the amplitude of the NTC region, and reduces the ignition delay time for both isomers by roughly a factor of 3. In the region in which two-stage ignition is observed, 680-825 K, the duration of the first ignition stage decreases sharply in the range 680-770 K, but is essentially flat above 770 K. Good quantitative agreement is found between the measurements and calculations for n-butane using a comprehensive model for butane ignition, including both delay times in the two-stage region, with substantial differences being observed for iso-butane, particularly in the NTC region. (author)

  16. Development and Benchmarking of a Hybrid PIC Code For Dense Plasmas and Fast Ignition

    SciTech Connect (OSTI)

    Witherspoon, F. Douglas; Welch, Dale R.; Thompson, John R.; MacFarlane, Joeseph J.; Phillips, Michael W.; Bruner, Nicki; Mostrom, Chris; Thoma, Carsten; Clark, R. E.; Bogatu, Nick; Kim, Jin-Soo; Galkin, Sergei; Golovkin, Igor E.; Woodruff, P. R.; Wu, Linchun; Messer, Sarah J.

    2014-05-20

    Radiation processes play an important role in the study of both fast ignition and other inertial confinement schemes, such as plasma jet driven magneto-inertial fusion, both in their effect on energy balance, and in generating diagnostic signals. In the latter case, warm and hot dense matter may be produced by the convergence of a plasma shell formed by the merging of an assembly of high Mach number plasma jets. This innovative approach has the potential advantage of creating matter of high energy densities in voluminous amount compared with high power lasers or particle beams. An important application of this technology is as a plasma liner for the flux compression of magnetized plasma to create ultra-high magnetic fields and burning plasmas. HyperV Technologies Corp. has been developing plasma jet accelerator technology in both coaxial and linear railgun geometries to produce plasma jets of sufficient mass, density, and velocity to create such imploding plasma liners. An enabling tool for the development of this technology is the ability to model the plasma dynamics, not only in the accelerators themselves, but also in the resulting magnetized target plasma and within the merging/interacting plasma jets during transport to the target. Welch pioneered numerical modeling of such plasmas (including for fast ignition) using the LSP simulation code. Lsp is an electromagnetic, parallelized, plasma simulation code under development since 1995. It has a number of innovative features making it uniquely suitable for modeling high energy density plasmas including a hybrid fluid model for electrons that allows electrons in dense plasmas to be modeled with a kinetic or fluid treatment as appropriate. In addition to in-house use at Voss Scientific, several groups carrying out research in Fast Ignition (LLNL, SNL, UCSD, AWE (UK), and Imperial College (UK)) also use LSP. A collaborative team consisting of HyperV Technologies Corp., Voss Scientific LLC, FAR-TECH, Inc., Prism Computational Sciences, Inc. and Advanced Energy Systems Inc. joined efforts to develop new physics and numerical models for LSP in several key areas to enhance the ability of LSP to model high energy density plasmas (HEDP). This final report details those efforts. Areas addressed in this research effort include: adding radiation transport to LSP, first in 2D and then fully 3D, extending the EMHD model to 3D, implementing more advanced radiation and electrode plasma boundary conditions, and installing more efficient implicit numerical algorithms to speed complex 2-D and 3-D computations. The new capabilities allow modeling of the dominant processes in high energy density plasmas, and further assist the development and optimization of plasma jet accelerators, with particular attention to MHD instabilities and plasma/wall interaction (based on physical models for ion drag friction and ablation/erosion of the electrodes). In the first funding cycle we implemented a solver for the radiation diffusion equation. To solve this equation in 2-D, we used finite-differencing and applied the parallelized sparse-matrix solvers in the PETSc library (Argonne National Laboratory) to the resulting system of equations. A database of the necessary coefficients for materials of interest was assembled using the PROPACEOS and ATBASE codes from Prism. The model was benchmarked against Prism's 1-D radiation hydrodynamics code HELIOS, and against experimental data obtained from HyperV's separately funded plasma jet accelerator development program. Work in the second funding cycle focused on extending the radiation diffusion model to full 3-D, continued development of the EMHD model, optimizing the direct-implicit model to speed up calculations, add in multiply ionized atoms, and improved the way boundary conditions are handled in LSP. These new LSP capabilities were then used, along with analytic calculations and Mach2 runs, to investigate plasma jet merging, plasma detachment and transport, restrike and advanced jet accelerator design. In addition, a strong linkage to diagnostic measureme

  17. Nuclear imaging of the fuel assembly in ignition experiments

    SciTech Connect (OSTI)

    Grim, G. P.; Guler, N.; Merrill, F. E.; Morgan, G. L.; Danly, C. R.; Volegov, P. L.; Wilde, C. H.; Wilson, D. C.; Clark, D. S.; Hinkel, D. E.; Jones, O. S.; Raman, K. S.; Izumi, N.; Fittinghoff, D. N.; Drury, O. B.; Alger, E. T.; Arnold, P. A.; Ashabranner, R. C.; Atherton, L. J.; Barrios, M. A.; Batha, S.; Bell, P. M.; Benedetti, L. R.; Berger, R. L.; Bernstein, L. A.; Berzins, L. V.; Betti, R.; Bhandarkar, S. D.; Bionta, R. M.; Bleuel, D. L.; Boehly, T. R.; Bond, E. J.; Bowers, M. W.; Bradley, D. K.; Brunton, G. K.; Buckles, R. A.; Burkhart, S. C.; Burr, R. F.; Caggiano, J. A.; Callahan, D. A.; Casey, D. T.; Castro, C.; Celliers, P. M.; Cerjan, C. J.; Chandler, G. A.; Choate, C.; Cohen, S. J.; Collins, G. W.; Cooper, G. W.; Cox, J. R.; Cradick, J. R.; Datte, P. S.; Dewald, E. L.; Di Nicola, P.; Di Nicola, J. M.; Divol, L.; Dixit, S. N.; Dylla-Spears, R.; Dzenitis, E. G.; Eckart, M. J.; Eder, D. C.; Edgell, D. H.; Edwards, M. J.; Eggert, J. H.; Ehrlich, R. B.; Erbert, G. V.; Fair, J.; Farley, D. R.; Felker, B.; Fortner, R. J.; Frenje, J. A.; Frieders, G.; Friedrich, S.; Gatu-Johnson, M.; Gibson, C. R.; Giraldez, E.; Glebov, V. Y.; Glenn, S. M.; Glenzer, S. H.; Gururangan, G.; Haan, S. W.; Hahn, K. D.; Hammel, B. A.; Hamza, A. V.; Hartouni, E. P.; Hatarik, R.; Hatchett, S. P.; Haynam, C.; Hermann, M. R.; Herrmann, H. W.; Hicks, D. G.; Holder, J. P.; Holunga, D. M.; Horner, J. B.; Hsing, W. W.; Huang, H.; Jackson, M. C.; Jancaitis, K. S.; Kalantar, D. H.; Kauffman, R. L.; Kauffman, M. I.; Khan, S. F.; Kilkenny, J. D.; Kimbrough, J. R.; Kirkwood, R.; Kline, J. L.; Knauer, J. P.; Knittel, K. M.; Koch, J. A.; Kohut, T. R.; Kozioziemski, B. J.; Krauter, K.; Krauter, G. W.; Kritcher, A. L.; Kroll, J.; Kyrala, G. A.; Fortune, K. N. La; LaCaille, G.; Lagin, L. J.; Land, T. A.; Landen, O. L.; Larson, D. W.; Latray, D. A.; Leeper, R. J.; Lewis, T. L.; LePape, S.; Lindl, J. D.; Lowe-Webb, R. R.; Ma, T.; MacGowan, B. J.; MacKinnon, A. J.; MacPhee, A. G.; Malone, R. M.; Malsbury, T. N.; Mapoles, E.; Marshall, C. D.; Mathisen, D. G.; McKenty, P.; McNaney, J. M.; Meezan, N. B.; Michel, P.; Milovich, J. L.; Moody, J. D.; Moore, A. S.; Moran, M. J.; Moreno, K.; Moses, E. I.; Munro, D. H.; Nathan, B. R.; Nelson, A. J.; Nikroo, A.; Olson, R. E.; Orth, C.; Pak, A. E.; Palma, E. S.; Parham, T. G.; Patel, P. K.; Patterson, R. W.; Petrasso, R. D.; Prasad, R.; Ralph, J. E.; Regan, S. P.; Rinderknecht, H.; Robey, H. F.; Ross, G. F.; Ruiz, C. L.; Se?guin, F. H.; Salmonson, J. D.; Sangster, T. C.; Sater, J. D.; Saunders, R. L.; Schneider, M. B.; Schneider, D. H.; Shaw, M. J.; Simanovskaia, N.; Spears, B. K.; Springer, P. T.; Stoeckl, C.; Stoeffl, W.; Suter, L. J.; Thomas, C. A.; Tommasini, R.; Town, R. P.; Traille, A. J.; Wonterghem, B. Van; Wallace, R. J.; Weaver, S.; Weber, S. V.; Wegner, P. J.; Whitman, P. K.; Widmann, K.; Widmayer, C. C.; Wood, R. D.; Young, B. K.; Zacharias, R. A.; Zylstra, A.

    2013-01-01

    First results from the analysis of neutron image data collected on implosions of cryogenically layered deuterium-tritium capsules during the 2011-2012 National Ignition Campaign are reported. The data span a variety of experimental designs aimed at increasing the stagnation pressure of the central hotspot and areal density of the surrounding fuel assembly. Images of neutrons produced by deuteriumtritium fusion reactions in the hotspot are presented, as well as images of neutrons that scatter in the surrounding dense fuel assembly. The image data are compared with 1D and 2D model predictions, and consistency checked using other diagnostic data. The results indicate that the size of the fusing hotspot is consistent with the model predictions, as well as other imaging data, while the overall size of the fuel assembly, inferred from the scattered neutron images, is systematically smaller than models prediction. Preliminary studies indicate these differences are consistent with a significant fraction (20%25%) of the initial deuterium-tritium fuel mass outside the compact fuel assembly, due either to low mode mass asymmetry or high mode 3D mix effects at the ablator-ice interface.

  18. Method for fabricating an ignitable heterogeneous stratified metal structure

    DOE Patents [OSTI]

    Barbee, T.W. Jr.; Weihs, T.

    1996-08-20

    A multilayer structure has a selectable: (1) propagating reaction front velocity V; (2) reaction initiation temperature attained by application of external energy; and (3) amount of energy delivered by a reaction of alternating unreacted layers of the multilayer structure. Because V is selectable and controllable, a variety of different applications for the multilayer structures are possible, including but not limited to their use as igniters, in joining applications, in fabrication of new materials, as smart materials and in medical applications and devices. The multilayer structure has a period D, and an energy release rate constant K. Two or more alternating unreacted layers are made of different materials and separated by reacted zones. The period D is equal to a sum of the widths of each single alternating reaction layer of a particular material, and also includes a sum of reacted zone widths, t{sub i}, in the period D. The multilayer structure has a selectable propagating reaction front velocity V, where V=K(1/D{sup n}){times}[1-(t{sub i}/D)] and n is about 0.8 to 1.2. 8 figs.

  19. Preliminary hazards analysis for the National Ignition Facility

    SciTech Connect (OSTI)

    Brereton, S.J.

    1993-10-01

    This report documents the Preliminary Hazards Analysis (PHA) for the National Ignition Facility (NIF). In summary, it provides: a general description of the facility and its operation; identification of hazards at the facility; and details of the hazards analysis, including inventories, bounding releases, consequences, and conclusions. As part of the safety analysis procedure set forth by DOE, a PHA must be performed for the NIF. The PHA characterizes the level of intrinsic potential hazard associated with a facility, and provides the basis for hazard classification. The hazard classification determines the level of safety documentation required, and the DOE Order governing the safety analysis. The hazard classification also determines the level of review and approval required for the safety analysis report. The hazards of primary concern associated with NIF are radiological and toxicological in nature. The hazard classification is determined by comparing facility inventories of radionuclides and chemicals with threshold values for the various hazard classification levels and by examining postulated bounding accidents associated with the hazards of greatest significance. Such postulated bounding accidents cannot take into account active mitigative features; they must assume the unmitigated consequences of a release, taking into account only passive safety features. In this way, the intrinsic hazard level of the facility can be ascertained.

  20. Dynamic control of a homogeneous charge compression ignition engine

    DOE Patents [OSTI]

    Duffy, Kevin P. (Metamora, IL); Mehresh, Parag (Peoria, IL); Schuh, David (Peoria, IL); Kieser, Andrew J. (Morton, IL); Hergart, Carl-Anders (Peoria, IL); Hardy, William L. (Peoria, IL); Rodman, Anthony (Chillicothe, IL); Liechty, Michael P. (Chillicothe, IL)

    2008-06-03

    A homogenous charge compression ignition engine is operated by compressing a charge mixture of air, exhaust and fuel in a combustion chamber to an autoignition condition of the fuel. The engine may facilitate a transition from a first combination of speed and load to a second combination of speed and load by changing the charge mixture and compression ratio. This may be accomplished in a consecutive engine cycle by adjusting both a fuel injector control signal and a variable valve control signal away from a nominal variable valve control signal. Thereafter in one or more subsequent engine cycles, more sluggish adjustments are made to at least one of a geometric compression ratio control signal and an exhaust gas recirculation control signal to allow the variable valve control signal to be readjusted back toward its nominal variable valve control signal setting. By readjusting the variable valve control signal back toward its nominal setting, the engine will be ready for another transition to a new combination of engine speed and load.

  1. Formative time of breakdown modeled for the ignition of air and n-butane mixtures using effective ionization coefficients

    SciTech Connect (OSTI)

    Kudryavtsev, A. A.; Popugaev, S. D.; Demidov, V. I.; Adams, S. F.; Jiao, C. Q.

    2008-12-15

    It is shown that simulations of ignition by electric arc discharge in n-butane and air mixtures have interesting features, which deviate from results obtained by simple extension of calculations based on methanelike fuels. In particular, it is demonstrated that lowering the temperature of the n-butane-air mixture before ignition under certain conditions will actually decrease the ignition stage time as well as the required electric field.

  2. Advances in Inertial Confinement Fusion at the National Ignition Facility (NIF)

    SciTech Connect (OSTI)

    Moses, E

    2009-10-15

    The 192-beam National Ignition Facility (NIF) at the Lawrence Livermore National Laboratory (LLNL) in Livermore, CA, is now operational and conducting experiments. NIF, the flagship facility of the U.S. Inertial Confinement Fusion (ICF) Program, will achieve high-energy-density conditions never previously obtained in the laboratory - temperatures over 100 million K, densities of 1,000 g/cm3, and pressures exceeding 100 billion atmospheres. Such conditions exist naturally only in the interiors of the stars and during thermonuclear burn. Demonstration of ignition and thermonuclear burn in the laboratory is a major NIF goal. To date, the NIF laser has demonstrated all pulse shape, beam quality, energy, and other specifications required to meet the ignition challenge. On March 10, 2009, the NIF laser delivered 1.1 MJ of ultraviolet laser energy to target chamber center, approximately 30 times more energy than any previous facility. The ignition program at NIF is the National Ignition Campaign (NIC), a national collaboration for ignition experimentation with participation from General Atomics, LLNL, Los Alamos National Laboratory (LANL), Sandia National Laboratories (SNL), and the University of Rochester Laboratory for Laser Energetics (LLE). The achievement of ignition at NIF will demonstrate the scientific feasibility of ICF and focus worldwide attention on fusion as a viable energy option. A particular energy concept under investigation is the LIFE (Laser Inertial Fusion Energy) scheme. The LIFE engine is inherently safe, minimizes proliferation concerns associated with the nuclear fuel cycle, and can provide a sustainable carbon-free energy generation solution in the 21st century. This talk will describe NIF and its potential as a user facility and an experimental platform for high-energy-density science, NIC, and the LIFE approach for clean, sustainable energy.

  3. Near Field Intensity Trends of Main Laser Alignment Images in the National Ignition Facility (NIF)

    SciTech Connect (OSTI)

    Leach, R R; Beltsar, I; Burkhart, S; Lowe-Webb, R; Kamm, V M; Salmon, T; Wilhelmsen, K

    2015-01-22

    The National Ignition Facility (NIF) utilizes 192 high-energy laser beams focused with enough power and precision on a hydrogen-filled spherical, cryogenic target to potentially initiate a fusion reaction. NIF has been operational for six years; during that time, thousands of successful laser firings or shots have been executed. Critical instrument measurements and camera images are carefully recorded for each shot. The result is a massive and complex database or ‘big data’ archive that can be used to investigate the state of the laser system at any point in its history or to locate and track trends in the laser operation over time. In this study, the optical light throughput for more than 1600 NIF shots for each of the 192 main laser beams and 48 quads was measured over a three year period from January 2009 to October 2012. The purpose was to verify that the variation in the transmission of light through the optics over time performed within design expectations during this time period. Differences between average or integrated intensity from images recorded by the input sensor package (ISP) and by the output sensor package (OSP) in the NIF beam-line were examined. A metric is described for quantifying changes in the integrated intensity measurements and was used to view potential trends. Results are presented for the NIF input and output sensor package trends and changes over the three year time-frame.

  4. A geophysical shock and air blast simulator at the National Ignition Facility

    SciTech Connect (OSTI)

    Fournier, K. B.; Brown, C. G.; May, M. J.; Compton, S.; Walton, O. R.; Shingleton, N.; Kane, J. O.; Holtmeier, G.; Loey, H.; Mirkarimi, P. B.; Dunlop, W. H.; Guyton, R. L.; Huffman, E.

    2014-09-01

    The energy partitioning energy coupling experiments at the National Ignition Facility (NIF) have been designed to measure simultaneously the coupling of energy from a laser-driven target into both ground shock and air blast overpressure to nearby media. The source target for the experiment is positioned at a known height above the ground-surface simulant and is heated by four beams from the NIF. The resulting target energy density and specific energy are equal to those of a low-yield nuclear device. The ground-shock stress waves and atmospheric overpressure waveforms that result in our test system are hydrodynamically scaled analogs of full-scale seismic and air blast phenomena. This report summarizes the development of the platform, the simulations, and calculations that underpin the physics measurements that are being made, and finally the data that were measured. Agreement between the data and simulation of the order of a factor of two to three is seen for air blast quantities such as peak overpressure. Historical underground test data for seismic phenomena measured sensor displacements; we measure the stresses generated in our ground-surrogate medium. We find factors-of-a-few agreement between our measured peak stresses and predictions with modern geophysical computer codes.

  5. n-Butane: Ignition delay measurements at high pressure and detailed chemical kinetic simulations

    SciTech Connect (OSTI)

    Healy, D.; Curran, H.J.; Donato, N.S.; Aul, C.J.; Petersen, E.L.; Zinner, C.M.; Bourque, G.

    2010-08-15

    Ignition delay time measurements were recorded at equivalence ratios of 0.3, 0.5, 1, and 2 for n-butane at pressures of approximately 1, 10, 20, 30 and 45 atm at temperatures from 690 to 1430 K in both a rapid compression machine and in a shock tube. A detailed chemical kinetic model consisting of 1328 reactions involving 230 species was constructed and used to validate the delay times. Moreover, this mechanism has been used to simulate previously published ignition delay times at atmospheric and higher pressure. Arrhenius-type ignition delay correlations were developed for temperatures greater than 1025 K which relate ignition delay time to temperature and concentration of the mixture. Furthermore, a detailed sensitivity analysis and a reaction pathway analysis were performed to give further insight to the chemistry at various conditions. When compared to existing data from the literature, the model performs quite well, and in several instances the conditions of earlier experiments were duplicated in the laboratory with overall good agreement. To the authors' knowledge, the present paper presents the most comprehensive set of ignition delay time experiments and kinetic model validation for n-butane oxidation in air. (author)

  6. A full fuel-cycle analysis of energy and emissions impacts of...

    Office of Scientific and Technical Information (OSTI)

    use in five types of motor vehicles--spark-ignition vehicles, compression-ignition vehicles, hybrid electric vehicles, battery-powered electric vehicles, and fuel-cell vehicles. ...

  7. Auto-ignition during instationary jet evolution of dimethyl ether (DME) in a high-pressure atmosphere

    SciTech Connect (OSTI)

    Fast, G.; Kuhn, D.; Class, A.G.; Maas, U.

    2009-01-15

    The auto-ignition process during transient injection of gaseous dimethyl ether (DME) in a constant high-pressure atmosphere is studied experimentally by laser-optical methods and compared with numerical calculations. With different non-intrusive measurement techniques jet properties and auto-ignition are investigated at high temporal and spatial resolution. The open jet penetrates a constant pressure oxidative atmosphere of up to 4 MPa. During the transient evolution, the fuel jet entrains air at up to 720 K. The subsequent auto-ignition of the ignitable part of the jet occurs simultaneously over a wide spatial extension. The ignition delay times are not affected by variation of the nozzle exit velocity. Thus, the low-temperature oxidation is slow compared with the shorter time scales of mixing, so that chemical kinetics is dominating the process. The typical two-stage ignition is resolved optically with high-speed shadowgraphy at a sampling rate of 10 kHz. The 2D fields of jet velocity and transient mixture fraction are measured phase-coupled with Particle Image Velocimetry (PIV) and Tracer Laser Induced Fluorescence (LIF) during the time-frame of ignition. The instationary Probability Density Functions (PDF) of mixture fraction are described very well by Beta functions within the complete area of the open jet. Additional 1D flamelet simulations of the auto-ignition process are computed with a detailed reaction mechanism for DME [S. Fischer, F. Dryer, H. Curran, Int. J. Chem. Kinet. 32 (12) (2000) 713-740; H. Curran, S. Fischer, F. Dryer, Int. J. Chem. Kinet. 32 (12) (2000) 741-759]. Calculated ignition delay times are in very good agreement with the measured mean ignition delay times of 3 ms. Supplemental flamelet simulations address the influence of DME and air temperature, pressure and strain. Underneath a critical strain rate the air temperature is identified to be the most sensitive factor on ignition delay time. (author)

  8. Application of Pulse Spark Discharges for Scale Prevention and Continuous Filtration Methods in Coal-Fired Power Plant

    SciTech Connect (OSTI)

    Cho, Young; Fridman, Alexander

    2012-06-30

    The overall objective of the present work was to develop a new scale-prevention technology by continuously precipitating and removing dissolved mineral ions (such as calcium and magnesium) in cooling water while the COC could be doubled from the present standard value of 3.5. The hypothesis of the present study was that if we could successfully precipitate and remove the excess calcium ions in cooling water, we could prevent condenser-tube fouling and at the same time double the COC. The approach in the study was to utilize pulse spark discharges directly in water to precipitate dissolved mineral ions in recirculating cooling water into relatively large suspended particles, which could be removed by a self-cleaning filter. The present study began with a basic scientific research to better understand the mechanism of pulse spark discharges in water and conducted a series of validation experiments using hard water in a laboratory cooling tower. Task 1 of the present work was to demonstrate if the spark discharge could precipitate the mineral ions in water. Task 2 was to demonstrate if the selfcleaning filter could continuously remove these precipitated calcium particles such that the blowdown could be eliminated or significantly reduced. Task 3 was to demonstrate if the scale could be prevented or minimized at condenser tubes with a COC of 8 or (almost) zero blowdown. In Task 1, we successfully completed the validation study that confirmed the precipitation of dissolved calcium ions in cooling water with the supporting data of calcium hardness over time as measured by a calcium ion probe. In Task 2, we confirmed through experimental tests that the self-cleaning filter could continuously remove precipitated calcium particles in a simulated laboratory cooling tower such that the blowdown could be eliminated or significantly reduced. In addition, chemical water analysis data were obtained which were used to confirm the COC calculation. In Task 3, we conducted a series of heat transfer fouling tests using a condenser heat exchanger in the laboratory cooling tower, from which we confirmed that the plasma water treatment technology could prevent or significantly mitigate mineral foulings in condenser tubes when compared with the no-treatment case. With the completion of the present work, a cooling water treatment technology using pulse spark discharges is currently ready for field-validation tests. The plasma water treatment technology is a true mechanical water softener with almost no maintenance, which continuously converts hard water to soft water spending a relatively small amount of energy. Such a mechanical water softener could find wide-spread applications to solve hard water problems both in industry and at home.

  9. Apparatus and method for igniting an in situ oil shale retort

    DOE Patents [OSTI]

    Chambers, Carlon C. (Grand Junction, CO)

    1981-01-01

    A method and apparatus for conducting such method are disclosed for igniting a fragmented permeable mass of formation particles in an in situ oil shale retort. The method is conducted by forming a hole through unfragmented formation to the fragmented mass. An oxygen-containing gas is introduced into the hole. A fuel is introduced into a portion of the hole spaced apart from the fragmented mass. The fuel and oxygen-containing gas mix forming a combustible mixture which is ignited for establishing a combustion zone in a portion of the hole spaced apart from the fragmented mass. The hot gas generated in the combustion zone is conducted from the hole into the fragmented mass for heating a portion of the fragmented mass above an ignition temperature of oil shale.

  10. Homogenous charge compression ignition engine having a cylinder including a high compression space

    DOE Patents [OSTI]

    Agama, Jorge R.; Fiveland, Scott B.; Maloney, Ronald P.; Faletti, James J.; Clarke, John M.

    2003-12-30

    The present invention relates generally to the field of homogeneous charge compression engines. In these engines, fuel is injected upstream or directly into the cylinder when the power piston is relatively close to its bottom dead center position. The fuel mixes with air in the cylinder as the power piston advances to create a relatively lean homogeneous mixture that preferably ignites when the power piston is relatively close to the top dead center position. However, if the ignition event occurs either earlier or later than desired, lowered performance, engine misfire, or even engine damage, can result. Thus, the present invention divides the homogeneous charge between a controlled volume higher compression space and a lower compression space to better control the start of ignition.

  11. Modeling and Experimental Investigation of Methylcyclohexane Ignition in a Rapid Compression Machine

    SciTech Connect (OSTI)

    Pitz, W J; Naik, C V; Mhaold?in, T N; Curran, H J; Orme, J P; Simmie, J M; Westbrook, C K

    2005-10-13

    A new mechanism for the oxidation of methylcyclohexane has been developed. The mechanism combined a newly-developed low temperature mechanism with a previously developed high temperature mechanism. Predictions from the chemical kinetic model have been compared to experimentally measured ignition delay times from a rapid compression machine. Predicted ignition delay times using the initial estimates of the methylcyclohexyl peroxy radical isomerization rate constants were much longer than those measured at low temperatures. The initial estimates of isomerization rate constants were modified based on the experimental findings of Gulati and Walker that indicate a much slower rate of isomerization. Predictions using the modified rate constants for isomerizations yielded faster ignition at lower temperatures that greatly improved the agreement between model predictions and the experimental data. These findings point to much slower isomerization rates for methylcyclohexyl peroxy radicals than previously expected.

  12. High-density carbon ablator ignition path with low-density gas-filled rugby hohlraum

    SciTech Connect (OSTI)

    Amendt, Peter; Ho, Darwin D.; Jones, Ogden S.

    2015-04-15

    A recent low gas-fill density (0.6?mg/cc {sup 4}He) cylindrical hohlraum experiment on the National Ignition Facility has shown high laser-coupling efficiency (>96%), reduced phenomenological laser drive corrections, and improved high-density carbon capsule implosion symmetry [Jones et al., Bull. Am. Phys. Soc. 59(15), 66 (2014)]. In this Letter, an ignition design using a large rugby-shaped hohlraum [Amendt et al., Phys. Plasmas 21, 112703 (2014)] for high energetics efficiency and symmetry control with the same low gas-fill density (0.6?mg/cc {sup 4}He) is developed as a potentially robust platform for demonstrating thermonuclear burn. The companion high-density carbon capsule for this hohlraum design is driven by an adiabat-shaped [Betti et al., Phys. Plasmas 9, 2277 (2002)] 4-shock drive profile for robust high gain (>10) 1-D ignition performance and large margin to 2-D perturbation growth.

  13. Report from the Integrated Modeling Panel at the Workshop on the Science of Ignition on NIF

    SciTech Connect (OSTI)

    Marinak, M; Lamb, D

    2012-07-03

    This section deals with multiphysics radiation hydrodynamics codes used to design and simulate targets in the ignition campaign. These topics encompass all the physical processes they model, and include consideration of any approximations necessary due to finite computer resources. The section focuses on what developments would have the highest impact on reducing uncertainties in modeling most relevant to experimental observations. It considers how the ICF codes should be employed in the ignition campaign. This includes a consideration of how the experiments can be best structured to test the physical models the codes employ.

  14. Fuel mixture stratification as a method for improving homogeneous charge compression ignition engine operation

    DOE Patents [OSTI]

    Dec, John E. (Livermore, CA); Sjoberg, Carl-Magnus G. (Livermore, CA)

    2006-10-31

    A method for slowing the heat-release rate in homogeneous charge compression ignition ("HCCI") engines that allows operation without excessive knock at higher engine loads than are possible with conventional HCCI. This method comprises injecting a fuel charge in a manner that creates a stratified fuel charge in the engine cylinder to provide a range of fuel concentrations in the in-cylinder gases (typically with enough oxygen for complete combustion) using a fuel with two-stage ignition fuel having appropriate cool-flame chemistry so that regions of different fuel concentrations autoignite sequentially.

  15. Improvement of performance and emissions of a compression ignition methanol engine with dimethyl ether

    SciTech Connect (OSTI)

    Guo, J.; Chikahisa, Takemi; Murayama, Tadashi; Miyano, Masaharu

    1994-10-01

    Dimethyl ether (DME) has very good compression ignition characteristics and can be converted from methanol using a {gamma}-alumina catalyst. In this study a torch ignition chamber (TIC) head with TIC close to the center of the main combustion chamber was designed for the TIC method. The possibility of improvements in reducing the quantities of DME and emission were investigated by optimizing the TIC position, methanol injection timing, DME injection timing, and intake and exhaust throttling. It was found that the necessary amount of DME was greatly reduced when optimizing methanol and DME injection timings. 2 refs., 16 figs., 1 tab.

  16. Semiconductor bridge, SCB, ignition studies of Al/CuO thermite

    SciTech Connect (OSTI)

    Bickes, R.W. Jr.; Wackerbarth, D.E.; Mohler, J.H.

    1997-04-01

    The authors briefly summarize semiconductor bridge operation and review their ignition studies of Al/CuO thermite as a function of the capacitor discharge unit (CDU) firing set capacitance, charge holder material and morphology of the CuO. Ignition thresholds were obtained using a brass charge holder and a non-conducting fiber-glass-epoxy composite material, G10. At - 18 C and a charge voltage of 50V, the capacitance thresholds were 30.1 {mu}F and 2.0 {mu}F respectively. They also present new data on electrostatic discharge (ESD) and radio frequency (RF) vulnerability tests.

  17. Prospects for high-gain, high yield National Ignition Facility targets driven by 2(omega) (green) light

    SciTech Connect (OSTI)

    Suter, L J; Glenzer, S; Haan, S; Hammel, B; Manes, K; Meezan, N; Moody, J; Spaeth, M; Divol, L; Oades, K; Stevenson, M

    2003-12-16

    The National Ignition Facility (NIF), operating at green (2{omega}) light, has the potential to drive ignition targets with significantly more energy than the 1.8 MJ it will produce with its baseline, blue (3{omega}) operations. This results in a greatly increased 'target design space', providing a number of exciting opportunities for fusion research. These include the prospect of ignition experiments with capsules absorbing energies in the vicinity of 1 MJ. This significant increase in capsule absorbed energy over the original designs at {approx}150 kJ could allow high-gain, high yield experiments on NIF. This paper reports the progress made exploring 2{omega} for NIF ignition, including potential 2{omega} laser performance, 2{omega} ignition target designs and 2{omega} Laser Plasma Interaction (LPI) studies.

  18. Two-dimensional simulations of thermonuclear burn in ignition-scale inertial confinement fusion targets under compressed axial magnetic fields

    SciTech Connect (OSTI)

    Perkins, L. J.; Logan, B. G.; Zimmerman, G. B.; Werner, C. J.

    2013-07-15

    We report for the first time on full 2-D radiation-hydrodynamic implosion simulations that explore the impact of highly compressed imposed magnetic fields on the ignition and burn of perturbed spherical implosions of ignition-scale cryogenic capsules. Using perturbations that highly convolute the cold fuel boundary of the hotspot and prevent ignition without applied fields, we impose initial axial seed fields of 20100 T (potentially attainable using present experimental methods) that compress to greater than 4 10{sup 4} T (400 MG) under implosion, thereby relaxing hotspot areal densities and pressures required for ignition and propagating burn by ?50%. The compressed field is high enough to suppress transverse electron heat conduction, and to allow alphas to couple energy into the hotspot even when highly deformed by large low-mode amplitudes. This might permit the recovery of ignition, or at least significant alpha particle heating, in submarginal capsules that would otherwise fail because of adverse hydrodynamic instabilities.

  19. Time-resolved measurements of the hot-electron population in ignition-scale experiments on the National Ignition Facility (invited)

    SciTech Connect (OSTI)

    Hohenberger, M. Stoeckl, C.; Albert, F.; Palmer, N. E.; Dppner, T.; Divol, L.; Dewald, E. L.; Bachmann, B.; MacPhee, A. G.; LaCaille, G.; Bradley, D. K.; Lee, J. J.

    2014-11-15

    In laser-driven inertial confinement fusion, hot electrons can preheat the fuel and prevent fusion-pellet compression to ignition conditions. Measuring the hot-electron population is key to designing an optimized ignition platform. The hot electrons in these high-intensity, laser-driven experiments, created via laser-plasma interactions, can be inferred from the bremsstrahlung generated by hot electrons interacting with the target. At the National Ignition Facility (NIF) [G. H. Miller, E. I. Moses, and C. R. Wuest, Opt. Eng. 43, 2841 (2004)], the filter-fluorescer x-ray (FFLEX) diagnostica multichannel, hard x-ray spectrometer operating in the 20500 keV rangehas been upgraded to provide fully time-resolved, absolute measurements of the bremsstrahlung spectrum with ?300 ps resolution. Initial time-resolved data exhibited significant background and low signal-to-noise ratio, leading to a redesign of the FFLEX housing and enhanced shielding around the detector. The FFLEX x-ray sensitivity was characterized with an absolutely calibrated, energy-dispersive high-purity germanium detector using the high-energy x-ray source at NSTec Livermore Operations over a range of K-shell fluorescence energies up to 111 keV (U K{sub ?}). The detectors impulse response function was measured in situ on NIF short-pulse (?90 ps) experiments, and in off-line tests.

  20. Use of plasma fuel systems at thermal power plants in Russia, Kazakhstan, China, and Turkey

    SciTech Connect (OSTI)

    Karpenko, E.I.; Karpenko, Y.E.; Messerle, V.E.; Ustimenko, A.B.

    2009-05-15

    The technology of plasma ignition of solid fuels is described, as well as its creation and development steps, the technoeconomic characteristics of plasma igniter systems, schemes of their installation in pulverized-coal boilers, and results of their application at pulverized coal-fired power plants.

  1. Process and apparatus for igniting a burner in an inert atmosphere

    DOE Patents [OSTI]

    Coolidge, Dennis W. (Katy, TX); Rinker, Franklin G. (Perrysburg, OH)

    1994-01-01

    According to this invention there is provided a process and apparatus for the ignition of a pilot burner in an inert atmosphere without substantially contaminating the inert atmosphere. The process includes the steps of providing a controlled amount of combustion air for a predetermined interval of time to the combustor then substantially simultaneously providing a controlled mixture of fuel and air to the pilot burner and to a flame generator. The controlled mixture of fuel and air to the flame generator is then periodically energized to produce a secondary flame. With the secondary flame the controlled mixture of fuel and air to the pilot burner and the combustion air is ignited to produce a pilot burner flame. The pilot burner flame is then used to ignited a mixture of main fuel and combustion air to produce a main burner flame. The main burner flame then is used to ignite a mixture of process derived fuel and combustion air to produce products of combustion for use as an inert gas in a heat treatment process.

  2. Prompt laser ignition and transition to detonation in a secondary explosive

    SciTech Connect (OSTI)

    Setchell, R.E.; Trott, W.M.

    1994-05-01

    A two-stage approach to achieving detonation in a secondary explosive was developed in previous studies in which ignition resulted from low-energy hot wires or from laser diodes. In the current study, this approach was examined in some detail for the case of ignition by a pulsed, solid-state (rod) laser. An initial series of experiments used Nd/glass, ND/YAG, and Ti/sapphire lasers to investigate the ignition of graphite-doped HMX in highly confined optical fixtures that incorporated a fast piezoelectric pressure transducer. Experimental parameters included the laser power history and the explosive column length. The results of these experiments guided a second series of experiments in which the ignition column explosive was terminated by a thin rupture disc in contact with a transition column of low density HMX or some other material. The transition column was terminated with a piezoelectric time-of-arrival detector for determining overall function times. Parameters investigated included different laser sources, rupture disc thicknesses, and the transition column explosive characteristics. Overall function times less than 50 microseconds were obtained, and trends established by the various parameter studies indicate that further reductions in function time can be achieved.

  3. Reactivity Controlled Compression Ignition (RCCI) Combustion on a Multi-Cylinder Light-Duty Diesel Engine

    SciTech Connect (OSTI)

    Curran, Scott; Hanson, Reed M; Wagner, Robert M

    2012-01-01

    Reactivity controlled compression ignition is a low-temperature combustion technique that has been shown, both in computational fluid dynamics modeling and single-cylinder experiments, to obtain diesel-like efficiency or better with ultra-low nitrogen oxide and soot emissions, while operating primarily on gasoline-like fuels. This paper investigates reactivity controlled compression ignition operation on a four-cylinder light-duty diesel engine with production-viable hardware using conventional gasoline and diesel fuel. Experimental results are presented over a wide speed and load range using a systematic approach for achieving successful steady-state reactivity controlled compression ignition combustion. The results demonstrated diesel-like efficiency or better over the operating range explored with low engine-out nitrogen oxide and soot emissions. A peak brake thermal efficiency of 39.0% was demonstrated for 2600 r/min and 6.9 bar brake mean effective pressure with nitrogen oxide emissions reduced by an order of magnitude compared to conventional diesel combustion operation. Reactivity controlled compression ignition emissions and efficiency results are compared to conventional diesel combustion operation on the same engine.

  4. Prompt laser ignition and transition to detonation in a secondary explosive

    SciTech Connect (OSTI)

    Setchell, R.E.; Trott, W.M.

    1995-05-01

    A two-stage approach to achieving detonation in a secondary explosive was developed in previous studies in which ignition resulted from low-energy hot wires or from laser diodes. In the current study, this approach was examined in some detail for the case of ignition by a pulsed, solid-state (rod) laser. An initial series of experiments used Nd/glass, Nd/YAG, and Ti/sapphire lasers to investigate the ignition of graphite-doped HMX in highly confined optical fixtures that incorporated a fast piezoelectric pressure transducer. Experimental parameters included the laser power history and the explosive column length. The results of these experiments guided a second series of experiments in which the ignition column explosive was terminated by a thin rupture disc in contact with a transition column of low-density HMX or some other material. The transition column was terminated with a piezoelectric time-of-arrival detector for determining overall function times. Parameters investigated included different laser sources, rupture disc thicknesses, and the transition column explosive characteristics. Overall function times less than 50 microseconds were obtained, and trends established by the various parameter studies indicate that further reductions in function time can be achieved.

  5. Experimental demonstration of early time, hohlraum radiation symmetry tuning for indirect drive ignition experiments

    SciTech Connect (OSTI)

    Dewald, E. L.; Milovich, J.; Thomas, C.; Sorce, C.; Glenn, S.; Landen, O. L.; Kline, J.

    2011-09-15

    Early time radiation symmetry at the capsule for indirect drive ignition on the National Ignition Facility (NIF) [G. H. Miller, E. I. Moses, and C. R. Wuest, Nucl. Fusion 44, 228 (2004)] will be inferred from the instantaneous soft x-ray re-emission pattern of a high-Z sphere replacing the ignition capsule. This technique was tested on the OMEGA laser facility [J. M. Soures, R. L. McCrory, T. Boehly et al., Laser Part. Beams 11, 317 (1991)] in near full ignition scale vacuum hohlraums using an equivalent experimental setup to the one planned for NIF. Two laser cones entering each laser entrance hole heat the hohlraums to radiation temperatures of 100 eV, mimicking the NIF ignition pulse foot drive. The experiments have demonstrated accuracies of {+-}1.5% ({+-}2%) in inferred P{sub 2}/P{sub 0} (P{sub 4}/P{sub 0}) Legendre mode incident flux asymmetry and consistency between 900 eV and 1200 eV re-emission patterns. We have also demonstrated the expected tuning capability of P{sub 2}/P{sub 0}, from positive (pole hot) to negative (waist hot), decreasing linearly with the inner/outer beams power fraction. P{sub 4}/P{sub 0} on the other hand shows very little variation with power fraction. We developed a simple analytical viewfactor model that is in good agreement with both measured P{sub 2}/P{sub 0} and P{sub 4}/P{sub 0} and their dependence on inner beam power fraction.

  6. Transition from cool flame to thermal flame in compression ignition process

    SciTech Connect (OSTI)

    Yamada, Hiroyuki; Suzaki, Kotaro; Goto, Yuichi; Tezaki, Atsumu

    2008-07-15

    The mechanism that initiates thermal flames in compression ignition has been studied. Experimentally, a homogeneous charge compression ignition (HCCI) engine was used with DME, n-heptane, and n-decane. Arrhenius plots of the heat release rate in the HCCI experiments showed that rates of heat release with DME, n-heptane, and n-decane exhibited a certain activation energy that is identical to that of the H{sub 2}O{sub 2} decomposition reaction. The same feature was observed in diesel engine operation using ordinary diesel fuel with advanced ignition timing to make ignition occur after the end of fuel injection. These experimental results were reproduced in nondimensional simulations using kinetic mechanisms for DME, n-heptane, and n-decane, the last being developed by extending the n-heptane mechanism. Methanol addition, which suppresses low-temperature oxidation (LTO) and delays the ignition timing, had no effect on the activation energy obtained from the Arrhenius plot of heat release rate. Nevertheless, methanol addition lowered the heat release rates during the prethermal flame process. This is because H{sub 2}O{sub 2} formation during cool flame was reduced by adding methanol. The mechanism during the transition process from cool flame to thermal flame can be explained quantitatively using thermal explosion theory, in which the rate-determining reaction is H{sub 2}O{sub 2} decomposition, assuming that heat release in this period is caused by partial oxidation of DME and HCHO initiated with the reaction with OH produced though H{sub 2}O{sub 2} decomposition. (author)

  7. A Concept Exploration Program in Fast Ignition Inertial Fusion — Final Report

    SciTech Connect (OSTI)

    Stephens, Richarad Burnite; Freeman, Richard R.; Van Woekom, L. D.; Key, M.; MacKinnon, Andrew J.; Wei, Mingsheng

    2014-02-27

    The Fast Ignition (FI) approach to Inertial Confinement Fusion (ICF) holds particular promise for fusion energy because the independently generated compression and ignition pulses allow ignition with less compression, resulting in (potentially) higher gain. Exploiting this concept effectively requires an understanding of the transport of electrons in prototypical geometries and at relevant densities and temperatures. Our consortium, which included General Atomics (GA), The Ohio State University (OSU), the University of California, San Diego (UCSD), University of California, Davis (UC-Davis), and Princeton University under this grant (~$850K/yr) and Lawrence Livermore National Laboratory (LLNL) under a companion grant, won awards in 2000, renewed in 2005, to investigate the physics of electron injection and transport relevant to the FI concept, which is crucial to understand electron transport in integral FI targets. In the last two years we have also been preparing diagnostics and starting to extend the work to electron transport into hot targets. A complementary effort, the Advanced Concept Exploration (ACE) program for Fast Ignition, was funded starting in 2006 to integrate this understanding into ignition schemes specifically suitable for the initial fast ignition attempts on OMEGA and National Ignition Facility (NIF), and during that time these two programs have been managed as a coordinated effort. This result of our 7+ years of effort has been substantial. Utilizing collaborations to access the most capable laser facilities around the world, we have developed an understanding that was summarized in a Fusion Science & Technology 2006, Special Issue on Fast Ignition. The author lists in the 20 articles in that issue are dominated by our group (we are first authors in four of them). Our group has published, or submitted 67 articles, including 1 in Nature, 2 Nature Physics, 10 Physical Review Letters, 8 Review of Scientific Instruments, and has been invited to give numerous talks at national and international conferences (including APS-DPP, IAEA, FIW). The advent of PW capabilities – at Rutherford Appleton Lab (UK) and then at Titan (LLNL) (2005 and 2006, respectively), was a major step toward experiments in ultra-high intensity high-energy FI relevant regime. The next step comes with the activation of OMEGA EP at LLE, followed shortly by NIF-ARC at LLNL. These capabilities allow production of hot dense material for electron transport studies. In this transitional period, considerable effort has been spent in developing the necessary tools and experiments for electron transport in hot and dense plasmas. In addition, substantial new data on electron generation and transport in metallic targets has been produced and analyzed. Progress in FI detailed in §2 is related to the Concept Exploration Program (CEP) objectives; this section is a summary of the publications and presentations listed in §5. This work has benefited from the synergy with work on related Department of Energy (DOE) grants, the Fusion Science Center and the Fast Ignition Advanced Concept Exploration grant, and from our interactions with overseas colleagues, primarily at Rutherford Appleton Laboratory in the UK, and the Institute for Laser Engineering in Japan.

  8. Effect of Premixed Charge Compression Ignition on Vehicle Fuel...

    Office of Energy Efficiency and Renewable Energy (EERE) Indexed Site

    Evaluation of 2010 Urea-SCR Technology for Hybrid Vehicles using PSAT System Simulations Vehicle Technologies Office Merit Review 2015: Impacts of Advanced Combustion Engines ...

  9. Pre-ignition confinement and deflagration violence in LX-10 and PBX 9501

    SciTech Connect (OSTI)

    Tringe, J. W. Glascoe, E. A.; McClelland, M. A.; Greenwood, D.; Chambers, R. D.; Springer, H. K.; Levie, H. W.

    2014-08-07

    In thermal explosions of the nitramine octahydro-1,3,5,7-tetranitro-1,3,5,7-tetrazocine (HMX)-based explosives LX-10 and PBX-9501, the pre-ignition spatial and temporal heating profile defines the ignition location. The ignition location then determines the extent of inertial confinement and the violence of the resulting deflagration. In this work, we present results of experiments in which ?23?g cylinders of LX-10 and PBX 9501 in thin-walled aluminum confinement vessels were subjected to identical heating profiles but which presented starkly different energy release signatures. Post-explosion LX-10 containment vessels were completely fragmented, while the PBX 9501 vessels were merely ruptured. Flash x-ray radiography images show that the initiation location for the LX-10 is a few mm farther from the end caps of the vessel relative to the initiation location of PBX 9501. This difference increases deflagration confinement for LX-10 at the time of ignition and extends the pressurization time during which the deflagration front propagates in the explosive. The variation in the initiation location, in turn, is determined by the thermal boundary conditions, which differ for these two explosives because of the larger coefficient of thermal expansion and greater thermal stability of the Viton binder in LX-10 relative to the estane and bis(2,2-dinitropropyl) acetal/formal binder of the PBX 9501. The thermal profile and initiation location were modeled for LX-10 using the hydrodynamics and structures code ALE3D; results indicate temperatures in the vicinity of the ignition location in excess of 274?C near the time of ignition. The conductive burn rates for these two explosives, as determined by flash x-ray radiography, are comparable in the range 0.10.2?mm/?s, somewhat faster than rates observed by strand burner experiments for explosives in the temperature range 150180?C and pressures up to 100?MPa. The thinnest-wall aluminum containment vessels presented here rupture at lower pressures, in the range 10?MPa, suggesting that moderately higher temperatures and pressures are present near the deflagration front. For these explosives, however the most important property for determining deflagration violence is the degree of inertial confinement.

  10. Advanced Liquid Natural Gas Onboard Storage System

    SciTech Connect (OSTI)

    Greg Harper; Charles Powars

    2003-10-31

    Cummins Westport Incorporated (CWI) has designed and developed a liquefied natural gas (LNG) vehicle fuel system that includes a reciprocating pump with the cold end submerged in LNG contained in a vacuum-jacketed tank. This system was tested and analyzed under the U.S. Department of Energy (DOE) Advanced LNG Onboard Storage System (ALOSS) program. The pumped LNG fuel system developed by CWI and tested under the ALOSS program is a high-pressure system designed for application on Class 8 trucks powered by CWI's ISX G engine, which employs high-pressure direct injection (HPDI) technology. A general ALOSS program objective was to demonstrate the feasibility and advantages of a pumped LNG fuel system relative to on-vehicle fuel systems that require the LNG to be ''conditioned'' to saturation pressures that exceeds the engine fuel pressure requirements. These advantages include the capability to store more fuel mass in given-size vehicle and station tanks, and simpler lower-cost LNG refueling stations that do not require conditioning equipment. Pumped LNG vehicle fuel systems are an alternative to conditioned LNG systems for spark-ignition natural gas and port-injection dual-fuel engines (which typically require about 100 psi), and they are required for HPDI engines (which require over 3,000 psi). The ALOSS program demonstrated the feasibility of a pumped LNG vehicle fuel system and the advantages of this design relative to systems that require conditioning the LNG to a saturation pressure exceeding the engine fuel pressure requirement. LNG tanks mounted on test carts and the CWI engineering truck were repeatedly filled with LNG saturated at 20 to 30 psig. More fuel mass was stored in the vehicle tanks as well as the station tank, and no conditioning equipment was required at the fueling station. The ALOSS program also demonstrated the general viability and specific performance of the CWI pumped LNG fuel system design. The system tested as part of this program is designed to be used on Class 8 trucks with CWI ISX G HPDI engines. Extensive test cart and engineering truck tests of the pump demonstrated good durability and the high-pressure performance needed for HPDI application. The LNG tanks manufactured by Taylor-Wharton passed SAE J2343 Recommended Practice drop tests and accelerated road-load vibration tests. NER and hold-time tests produced highly consistent results. Additional tests confirmed the design adequacy of the liquid level sensor, vaporizer, ullage volume, and other fuel system components. While the testing work performed under this program focused on a high-pressure pumped LNG fuel system design, the results also validate the feasibility of a low-pressure pumped fuel system. A low-pressure pumped fuel system could incorporate various design refinements including a simpler and lighter-weight pump, which would decrease costs somewhat relative to a high-pressure system.

  11. Chemical Kinetic Reaction Mechanisms for Combustion of Hydrocarbon and Other Types of Chemical Fuels

    DOE Data Explorer [Office of Scientific and Technical Information (OSTI)]

    Reaction mechanisms have been tested and validated extensively through comparisons between computed results and measured data from laboratory experiments (e.g., shock tubes, laminar flames, rapid compression machines, flow reactors, stirred reactors) and from practical systems (e.g., diesel engines, spark-ignition engines, homogeneous charge, compression ignition (HCCI) engines). These kinetic models are used to examine a wide range of combustion systems.

  12. Rotary engine cooling system

    SciTech Connect (OSTI)

    Jones, C.

    1988-07-26

    A rotary internal combustion engine is described comprising: a rotor housing forming a trochoidal cavity therein; an insert of refractory material received in the recess, an element of a fuel injection and ignition system extending through the housing and insert bores, and the housing having cooling passages extending therethrough. The cooling passages are comprised of drilled holes.

  13. 2015 UTSR Poster Presentations Prediction of Auto-Ignition Regimes...

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Bond Coats for Thermal Barrier Coating Systems Based on High Entropy Alloys Derek Hass, DVTI Autoignition of a Jet-A Spray in a Hot, Vitiated Air Flow Aimee Williams, Georgia...

  14. Zone heated inlet ignited diesel particulate filter regeneration

    DOE Patents [OSTI]

    Gonze, Eugene V [Pinckney, MI; Ament, Frank [Troy, MI

    2012-06-26

    An exhaust system that processes exhaust generated by an engine is provided. The system includes: a particulate filter (PF) that is disposed downstream of the engine and that filters particulates from the exhaust; and a grid that includes electrically resistive material that is segmented by non-conductive material into a plurality of zones and wherein the grid is applied to an exterior upstream surface of the PF.

  15. Ignition of a combustible gas mixture by a high-current electric discharge in a closed volume

    SciTech Connect (OSTI)

    Berezhetskaya, N. K.; Gritsinin, S. I.; Kop'ev, V. A.; Kossyi, I. A.; Kuleshov, P. S.; Popov, N. A.; Starik, A. M.; Tarasova, N. M.

    2009-06-15

    Results are presented from experimental studies and numerical calculations of the ignition of a stoichiometric CH{sub 4}: O{sub 2} gas mixture by a high-current gliding discharge. It is shown that this type of discharge generates an axially propagating thermal wave (precursor) that penetrates into the gas medium and leads to fast gas heating. This process is followed by an almost simultaneous ignition of the gas mixture over the entire reactor volume.

  16. The effect of diluent gases on ignition delay times in the shock tube and in the rapid compression machine

    SciTech Connect (OSTI)

    Wuermel, J.; Silke, E.J.; Curran, H.J.; O Conaire, M.S.; Simmie, J.M.

    2007-10-15

    The diluent gas used in the preparation of test fuel/oxygen mixtures is inert and does not take part in the chemical reaction. However, it does have an effect on the measured ignition delay time both in rapid compression machines and in shock tubes - argon decelerates ignition in the RCM, but accelerates it in the shock tube under some conditions. This opposite effect is due to the times scales involved in these experimental devices. Typical ignition delay times in the RCM are in the region of 1-200 ms, while those in the shock tube are much shorter (10-1000 {mu}s). Comparative RCM experiments and simulations for helium, argon, xenon, and nitrogen have shown extreme heat loss in the postcompression period, particularly for helium. Autoignition measurements of 2,3-dimethylpentane have highlighted a direct dependency of ignition delay time on the type of diluent used, where longer ignition delay time were recorded with argon. This increased ignition delay time is due to the extreme cooling of argon in the postcompression period. This observation was strengthened by comparative experiments with helium and argon, where the diluent effect was even stronger for helium, caused by its higher thermal conductivity. In the shock tube, the diluent effect is opposite to that in the RCM. For dilute mixtures of isooctane, calculations have predicted that mixtures with argon will ignite faster than those with nitrogen, based on the relative heat capacities of the two diluent gases. Overall, we conclude that the choice of diluent gases in experimental devices must be made with care, as ignition delay times can depend strongly on the type of diluent gas used. (author)

  17. Modeling the Auto-Ignition of Biodiesel Blends with a Multi-Step Model

    SciTech Connect (OSTI)

    Toulson, Dr. Elisa; Allen, Casey M; Miller, Dennis J; McFarlane, Joanna; Schock, Harold; Lee, Tonghun

    2011-01-01

    There is growing interest in using biodiesel in place of or in blends with petrodiesel in diesel engines; however, biodiesel oxidation chemistry is complicated to directly model and existing surrogate kinetic models are very large, making them computationally expensive. The present study describes a method for predicting the ignition behavior of blends of n-heptane and methyl butanoate, fuels whose blends have been used in the past as a surrogate for biodiesel. The autoignition is predicted using a multistep (8-step) model in order to reduce computational time and make this a viable tool for implementation into engine simulation codes. A detailed reaction mechanism for n-heptane-methyl butanoate blends was used as a basis for validating the multistep model results. The ignition delay trends predicted by the multistep model for the n-heptane-methyl butanoate blends matched well with that of the detailed CHEMKIN model for the majority of conditions tested.

  18. SHOCK INITIATION EXPERIMENTS ON THE TATB BASED EXPLOSIVE RX-03-GO WITH IGNITION AND GROWTH MODELING

    SciTech Connect (OSTI)

    Vandersall, K S; Garcia, F; Tarver, C M

    2009-06-23

    Shock initiation experiments on the TATB based explosive RX-03-GO (92.5% TATB, 7.5% Cytop A by weight) were performed to obtain in-situ pressure gauge data, characterize the run-distance-to-detonation behavior, and calculate Ignition and Growth modeling parameters. A 101 mm diameter propellant driven gas gun was utilized to initiate the explosive sample with manganin piezoresistive pressure gauge packages placed between sample slices. The RX-03-GO formulation utilized is similar to that of LX-17 (92.5% TATB, 7.5% Kel-f by weight) with the notable differences of a new binder material and TATB that has been dissolved and recrystallized in order to improve the purity and morphology. The shock sensitivity will be compared with that of prior data on LX-17 and other TATB formulations. Ignition and Growth modeling parameters were obtained with a reasonable fit to the experimental data.

  19. Summary of the first neutron image data collected at the National Ignition Facility

    SciTech Connect (OSTI)

    Grim, G P; Archuleta, T N; Aragonez, R J; Atkinson, D P; Batha, S H; Barrios, M A; Bower, D E; Bradley, D K; Buckles, R A; Clark, D D; Clark, D J; Cradick, J R; Danly, C; Drury, O B; Fatherley, V E; Finch, J P; Garcia, F P; Gallegos, R A; Guler, N; Glenn, S M; Hsu, A H; Izumi, N; Jaramillo, S A; Kyrala, G A; Pape, S L; Loomis, E N; Mares, D; Martinson, D D; Ma, T; MacKinnon, A J; Merrill, F E; Morgan, G L; Munson, C; Murphy, T J; Polk, P J; Schmidt, D W; Tommasini, T; Tregillis, I L; Valdez, A C; Volegov, P L; Wang, T F; Wilde, C H; Wilke, M D; Wilson, D C; Dzenitis, J M; Felker, B; Fittinghoff, D N; Frank, M; Liddick, S N; Moran, M J; Roberson, G P; Weiss, P B; Kauffman, M I; Lutz, S S; Malone, R M; Traille, A

    2011-11-01

    A summary of data and results from the first neutron images produced by the National Ignition Facility (NIF), Lawrence Livermore National Laboratory, Livermore, CA, USA are presented. An overview of the neutron imaging technique is presented, as well as a synopsis of the data collected and measurements made to date. Data form directly driven, DT filled microballoons, as well as, indirectly driven, cryogenically layered ignition experiments are presented. The data presented show that the primary cores from directly driven implosions are approximately twice as large, 64 {+-} 3 {mu}m, as indirect cores 25 {+-} 4 and 29 {+-} 4 {mu}m and more asymmetric, P2/P0 = 47% vs. -14% and 7%. Further, comparison with the size and shape of X-ray image data on the same implosions show good agreement, indicating X-ray emission is dominated by the hot regions of the implosion.

  20. Extending operating range of a homogeneous charge compression ignition engine via cylinder deactivation

    DOE Patents [OSTI]

    Hergart, Carl-Anders; Hardy, William L.; Duffy, Kevin P.; Liechty, Michael P.

    2008-05-27

    An HCCI engine has the ability to operate over a large load range by utilizing a lower cetane distillate diesel fuel to increase ignition delay. This permits more stable operation at high loads by avoidance of premature combustion before top dead center. During low load conditions, a portion of the engines cylinders are deactivated so that the remaining cylinders can operate at a pseudo higher load while the overall engine exhibits behavior typical of a relatively low load.

  1. HEC-DPSSL 2012 Workshop, NIF Tour: National Ignition Facility & Photon

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Science NIF Tour TEXT SIZE Workshops About Organizing Committee Agenda Deadlines Abstract Submission Venue NIF Tour Directions Lake Tahoe Workshop Sign-up NIF Tour Non-US Citizen Deadline: July 11, 2012 US Citizen Deadline: August 10, 2012 Lawrence Livermore National Laboratory is home to the National Ignition Facility (NIF). NIF is a national resource — a unique experimental facility addressing compelling national security, energy, and science missions. NIF's 192 powerful laser beams,

  2. Modeling the Number of Ignitions Following an Earthquake: Developing Prediction Limits for Overdispersed Count Data

    Office of Environmental Management (EM)

    LA-UR-11-01857 Approved for public release; distribution I unlimited. Title: Modeling the Number of Ignitions Following an Earthquake: Developing Prediction Limits for Overdispersed Count Data Authors: Elizabeth J. Kelly and Raymond N. Tell Intended Use: Deliverable to SB-TS: Safety Basis Technical Services Los Alamos National Laboratory, an affirmative action/equal opportunity employer, is operated by the Los Alamos National Security, LLC for the National Nuclear Security Administration of the

  3. Isobutane ignition delay time measurements at high pressure and detailed chemical kinetic simulations

    SciTech Connect (OSTI)

    Healy, D.; Curran, H.J.; Donato, N.S.; Aul, C.J.; Petersen, E.L.; Zinner, C.M.; Bourque, G.

    2010-08-15

    Rapid compression machine and shock-tube ignition experiments were performed for real fuel/air isobutane mixtures at equivalence ratios of 0.3, 0.5, 1, and 2. The wide range of experimental conditions included temperatures from 590 to 1567 K at pressures of approximately 1, 10, 20, and 30 atm. These data represent the most comprehensive set of experiments currently available for isobutane oxidation and further accentuate the complementary attributes of the two techniques toward high-pressure oxidation experiments over a wide range of temperatures. The experimental results were used to validate a detailed chemical kinetic model composed of 1328 reactions involving 230 species. This mechanism has been successfully used to simulate previously published ignition delay times as well. A thorough sensitivity analysis was performed to gain further insight to the chemical processes occurring at various conditions. Additionally, useful ignition delay time correlations were developed for temperatures greater than 1025 K. Comparisons are also made with available isobutane data from the literature, as well as with 100% n-butane and 50-50% n-butane-isobutane mixtures in air that were presented by the authors in recent studies. In general, the kinetic model shows excellent agreement with the data over the wide range of conditions of the present study. (author)

  4. Summary of the First Neutron Image Data Collected at the National Ignition Facility

    SciTech Connect (OSTI)

    Grim, G P; Aragonez, R J; Batha, S H; Clark, D D; Clark, D J; Clark, D J; Fatherley, V E; Finch, J P; Garcia, F P; Gallegos, R A; Guler, N; Hsu, A H; Jaramillo, S A; Loomis, E N; Mares, D; Martinson, D D; Merrill, F E; Morgan, G L; Munson, C; Murphy, T J; Polk, P J; Schmidt, D W; Tregillis, I L; Valdez, A C; Volegov, P L; Wang, T.-S. F; Wilde, C H; Wilke, M D; Wilson, D C; Atkinson, D P; Bower, D E; Drury, O B; Dzenitis, J M; Felker, B; Fittinghoff, D N; Frank, M; Liddick, S N; Moran, M J; Roberson, G P; Weiss, P; Buckles, R A; Cradick, J R; Kaufman, M I; Lutz, S S; Malone, R M

    2011-11-01

    A summary of data and results from the first neutron images produced by the National Ignition Facility (NIF), Lawrence Livermore National Laboratory, Livermore, CA, USA are presented. An overview of the neutron imaging technique is presented, as well as a synopsis of the data collected and measurements made to date. Data form directly driven, DT filled microballoons, as well as, indirectly driven, cryogenically layered ignition experiments are presented. The data presented show that the primary cores from directly driven implosions are approximately twice as large, 64 +/- 3 um, as indirect cores (25 +/- 4 and 29 +/- 4 um and more asymmetric, P2/P0 = 47% vs. -14% and -7%. Further, comparison with the size and shape of X-ray image data from on the same implosions show good agreement, indicating X-ray emission is dominated by the hot regions of the implosion. This work was performed for the U.S. Department of Energy, National Nuclear Security Administration and by the National Ignition Campaign partners; Lawrence Livermore National Laboratory (LLNL), University of Rochester -Laboratory for Laser Energetics (LLE), General Atomics(GA), Los Alamos National Laboratory (LANL), Sandia National Laboratory (SNL). Other contributors include Lawrence Berkeley National Laboratory (LBNL), Massachusetts Institute of Technology (MIT), Atomic Weapons Establishment (AWE), England, and Commissariat `a l Energie Atomique (CEA), France.

  5. Underwater vapor phase burning of aluminum particles and on aluminum ignition during steam explosions

    SciTech Connect (OSTI)

    Epstein, M. )

    1991-09-01

    Recently reported experimental studies on aluminum-water steam explosions indicate that there may be a critical metal temperature at which the process changes over from a physical explosion to one which is very violent and involves the rapid liberation of chemical energy. In this report we examine the hypothesis that vapor-phase burning of aluminum is a necessary condition for the occurrence of such ignition-type'' steam explosions. An available two-phase stagnation flow film-boiling model is used to calculate the steam flux to the vaporizing aluminum surface. Combining this calculation with the notion that there is an upper limit to the magnitude of the metal vaporization rate at which the reaction regime must change from vapor phase to surface burning, leads to prediction of the critical metal surface temperature below which vapor phase burning is impossible. The critical temperature is predicted for both the aluminum-water pre-mixture configuration in which coarse drops of aluminum are falling freely through water and for the finely-fragmented aluminum drops in the wake of the pressure shock that triggers'' the explosion. Vapor phase burning is predicted to be possible during the pre-mixture phase but not very likely during the trigger phase of a steam explosion. The implications of these findings in terms of the validity of the hypothesis that ignition may begin with the vapor phase burning of aluminum is discussed. Recently postulated, alternative mechanisms of underwater aluminum ignition are also discussed.

  6. Underwater vapor phase burning of aluminum particles and on aluminum ignition during steam explosions

    SciTech Connect (OSTI)

    Epstein, M.

    1991-09-01

    Recently reported experimental studies on aluminum-water steam explosions indicate that there may be a critical metal temperature at which the process changes over from a physical explosion to one which is very violent and involves the rapid liberation of chemical energy. In this report we examine the hypothesis that vapor-phase burning of aluminum is a necessary condition for the occurrence of such ``ignition-type`` steam explosions. An available two-phase stagnation flow film-boiling model is used to calculate the steam flux to the vaporizing aluminum surface. Combining this calculation with the notion that there is an upper limit to the magnitude of the metal vaporization rate at which the reaction regime must change from vapor phase to surface burning, leads to prediction of the critical metal surface temperature below which vapor phase burning is impossible. The critical temperature is predicted for both the aluminum-water pre-mixture configuration in which coarse drops of aluminum are falling freely through water and for the finely-fragmented aluminum drops in the wake of the pressure shock that ``triggers`` the explosion. Vapor phase burning is predicted to be possible during the pre-mixture phase but not very likely during the trigger phase of a steam explosion. The implications of these findings in terms of the validity of the hypothesis that ignition may begin with the vapor phase burning of aluminum is discussed. Recently postulated, alternative mechanisms of underwater aluminum ignition are also discussed.

  7. Activation of Air and Utilities in the National Ignition Facility

    SciTech Connect (OSTI)

    Khater, H; Pohl, B; Brererton, S

    2010-04-08

    Detailed 3-D modeling of the NIF facility is developed to accurately simulate the radiation environment within the NIF. Neutrons streaming outside the NIF Target Chamber will activate the air present inside the Target Bay and the Ar gas inside the laser tubes. Smaller levels of activity are also generated in the Switchyard air and in the Ar portion of the SY laser beam path. The impact of neutron activation of utilities located inside the Target Bay is analyzed for variety of shot types. The impact of activating TB utilities on dose received by maintenance personnel post-shot is analyzed. The current NIF facility model includes all important features of the Target Chamber, shielding system, and building configuration. Flow of activated air from the Target Bay is controlled by the HVAC system. The amount of activated Target Bay air released through the stack is very small and does not pose significant hazard to personnel or the environment. Activation of Switchyard air is negligible. Activation of Target Bay utilities result in a manageable dose rate environment post high yield (20 MJ) shots. The levels of activation generated in air and utilities during D-D and THD shots are small and do not impact work planning post shots.

  8. Fabrication and Spark plasma sintering of nanostructured bismuth telluride (Bi{sub 2}Te{sub 3})

    SciTech Connect (OSTI)

    Saleemi, Mohsin; Toprak, Muhammet S.; Li, Shanghua; Johnsson, Mats; Muhammed, Mamoun

    2012-06-26

    Thermoelectric (TE) devices can harvest residual low-grade waste heat energy. Bismuth telluride (Bi{sub 2}Te{sub 3}) and its alloys are mostly used TE materials in the bulk form for making TE modules. We report a simple, fast and very high yield synthetic process for the bulk Bi{sub 2}Te{sub 3} nanopowders with hexagonal plate like morphology. Spark plasma sintering (SPS) process has been optimized in order to preserve nanostructure while achieving a high compaction density of the pellets. Electron microscopy analysis was used to determine the effect of SPS parameters during compaction on the grain growth. Optimal conditions for the fabricated nanopowder was determined as 673 K, 70 MPa pressure with no holding time, which resulted in average lateral grain size in the range of 165-190 nm for a compact density of 98%. About 50% reduction of thermal conductivity was observed as compared to its bulk counterparts, revealing the feasibility of suggested route in the preservation of nanostructure and enhanced phonon scattering.

  9. Reactor Chamber and Balance-of-Plant Characteristics for a Fast-Ignition Heavy-Ion Fusion Power Plant

    SciTech Connect (OSTI)

    Medin, Stanislav; Churazov, Mikhail; Koshkarev, Dmitri; Sharkov, Boris; Orlov, Yurii; Suslin, Viktor; Zemskov, Eugeni

    2003-05-15

    The concept of a fast-ignition heavy-ion fusion (FIHIF) power plant involves a cylindrical target and superhigh energy ion beams. The driver produces one plus/minus charge state multimass platinum ions with energy of 100 GeV. The driver efficiency and the target gain are taken as 0.25 and 100, respectively. The preliminary data on the energy fluxes delivered to the reactor chamber wall by the 500-MJ fusion yield are presented. The reactor chamber designed has two sections. In the first section, the microexplosions occur, and in the second section of bigger volume the expansion and condensation of vapors take place. The response of the blanket and the thin liquid film at the first-wall surface is evaluated. Lithium-lead eutectic is taken as a coolant. The evaporated mass and the condensation time are estimated, taking into account major thermophysical effects. The estimated neutron spectrum from the FIHIF target gives an average neutron energy of 11.9 MeV. The mechanical stresses in the construction material due to neutron energy release are evaluated. The outlet coolant chamber temperature is taken as 550 deg. C. The heat conversion system consisting of three coolant loops provides a net efficiency of the FIHIF power plant of 0.37.

  10. Final Project Report "Advanced Concept Exploration For Fast Ignition Science Program"

    SciTech Connect (OSTI)

    STEPHENS, Richard B.; McLEAN, Harry M.; THEOBALD, Wolfgang; AKLI, Kramer; BEG, Farhat N.; SENTOKU, Yasuiko; SCHUMACHER, Douglas; WEI, Mingsheng S.

    2014-01-31

    The Fast Ignition (FI) Concept for Inertial Confinement Fusion has the potential to provide a significant advance in the technical attractiveness of Inertial Fusion Energy (IFE) reactors. FI differs from conventional central hot spot (CHS) target ignition by decoupling compression from heating: using the laser (or heavy ion beam or Z pinch) drive pulse (10s of ns) to create a dense fuel and a second, much shorter (~10 ps) high intensity pulse to ignite a small region of it. There are two major physics issues concerning this concept; controlling the laser-induced generation of large electron currents and their propagation through high density plasmas. This project has addressed these two significant scientific issues in Relativistic High Energy Density (RHED) physics. Learning to control relativistic laser matter interaction (and the limits and potential thereof) will enable a wide range of applications. While these physics issues are of specific interest to inertial fusion energy science, they are also important for a wide range of other HED phenomena, including high energy ion beam generation, isochoric heating of materials, and the development of high brightness x-ray sources. Generating, controlling, and understanding the extreme conditions needed to advance this science has proved to be challenging: Our studies have pushed the boundaries of physics understanding and are at the very limits of experimental, diagnostic, and simulation capabilities in high energy density laboratory physics (HEDLP). Our research strategy has been based on pursuing the fundamental physics underlying the Fast Ignition (FI) concept. We have performed comprehensive study of electron generation and transport in fast-ignition targets with experiments, theory, and numerical modeling. A major issue is that the electrons produced in these experiments cannot be measured directlyonly effects due to their transport. We focused mainly on x-ray continuum photons from bremsstrahlung and x-ray line radiation from K-shell fluorescence. Integrated experiments, which combine target compression with short-pulse laser heating, yield additional information on target heating efficiency. This indirect way of studying the underlying behavior of the electrons must be validated with computational modeling to understand the physics and improve the design. This program execution required a large, well-organized team and it was managed by a joint Collaboration between General Atomics (GA), Lawrence Livermore National Laboratory (LLNL), and the Laboratory for Laser Energetics (LLE). The Collaboration was formed 8 years ago to understand the physics issues of the Fast Ignition concept, building on the strengths of each partner. GA fulfills its responsibilities jointly with the University of California, San Diego (UCSD), The Ohio State University (OSU) and the University of Nevada at Reno (UNR). Since RHED physics is pursued vigorously in many countries, international researchers have been an important part of our efforts to make progress. The division of responsibility was as follows: (1) LLE had primary leadership for channeling studies and the integrated energy transfer, (2) LLNL led the development of measurement methods, analysis, and deployment of diagnostics, and (3) GA together with UCSD, OSU and UNR studied the detailed energy-transfer physics. The experimental program was carried out using the Titan laser at the Jupiter Laser Facility at LLNL, the OMEGA and OMEGA EP lasers at LLE and the Texas Petawatt laser (TPW) at UT Austin. Modeling has been pursued on large computing facilities at LLNL, OSU, and UCSD using codes developed (by us and others) within the HEDLP program, commercial codes, and by leveraging existing supercomputer codes developed by the NNSA ICF program. This Consortium brought together all the componentsresources, facilities, and personnelnecessary to accomplish its aggressive goals. The ACE Program has been strongly collaborative, taking advantage of the expertise of the participating institutions to provide a research effort

  11. Stability of shocks relating to the shock ignition inertial fusion energy scheme

    SciTech Connect (OSTI)

    Davie, C. J. Bush, I. A.; Evans, R. G.

    2014-08-15

    Motivated by the shock ignition approach to improve the performance of inertial fusion targets, we make a series of studies of the stability of shock waves in planar and converging geometries. We examine stability of shocks moving through distorted material and driving shocks with non-uniform pressure profiles. We then apply a fully 3D perturbation, following this spherically converging shock through collapse to a distorted plane, bounce and reflection into an outgoing perturbed, broadly spherical shock wave. We find broad shock stability even under quite extreme perturbation.

  12. Two stroke homogenous charge compression ignition engine with pulsed air supplier

    DOE Patents [OSTI]

    Clarke, John M. (Chillicothe, IL)

    2003-08-05

    A two stroke homogenous charge compression ignition engine includes a volume pulsed air supplier, such as a piston driven pump, for efficient scavenging. The usage of a homogenous charge tends to decrease emissions. The use of a volume pulsed air supplier in conjunction with conventional poppet type intake and exhaust valves results in a relatively efficient scavenging mode for the engine. The engine preferably includes features that permit valving event timing, air pulse event timing and injection event timing to be varied relative to engine crankshaft angle. The principle use of the invention lies in improving diesel engines.

  13. Construction safety program for the National Ignition Facility Appendix A: Safety Requirements

    SciTech Connect (OSTI)

    Cerruti, S.J.

    1997-01-14

    These rules apply to all LLNL employees, non-LLNL employees (including contract labor, supplemental labor, vendors, personnel matrixed/assigned from other National Laboratories, participating guests, visitors and students) and construction contractors/subcontractors. The General Safety and Health rules shall be used by management to promote accident prevention through indoctrination, safety and health training and on-the-job application. As a condition for contracts award, all contractors and subcontractors and their employees must certify on Form S & H A-1 that they have read and understand, or have been briefed and understand, the National Ignition Facility OCIP Project General Safety Rules.

  14. Heavy-Duty Stoichiometric Compression Ignition Engine with Improved Fuel Economy over Alternative Technologies for Meeting 2010 On-Highway Emission

    SciTech Connect (OSTI)

    Kirby J. Baumgard; Richard E. Winsor

    2009-12-31

    The objectives of the reported work were: to apply the stoichiometric compression ignition (SCI) concept to a 9.0 liter diesel engine; to obtain engine-out NO{sub x} and PM exhaust emissions so that the engine can meet 2010 on-highway emission standards by applying a three-way catalyst for NO{sub x} control and a particulate filter for PM control; and to simulate an optimize the engine and air system to approach 50% thermal efficiency using variable valve actuation and electric turbo compounding. The work demonstrated that an advanced diesel engine can be operated at stoichiometric conditions with reasonable particulate and NOx emissions at full power and peak torque conditions; calculated that the SCI engine will operate at 42% brake thermal efficiency without advanced hardware, turbocompounding, or waste heat recovery; and determined that EGR is not necessary for this advanced concept engine, and this greatly simplifies the concept.

  15. The operation results with the modified charging equipment and ignition furnace at Kwangyang No. 2 sinter plant

    SciTech Connect (OSTI)

    Lee, K.J.; Pi, Y.J.; Kim, J.R.; Lee, J.N.

    1996-12-31

    There will be another blast furnace, the production capacity of which is 3.0 million tonnes per year in 1999 and mini mill plant, the production capacity of which is 1.8 million tonnes per year in 1996 at Kwangyang Works. Therefore, the coke oven gas and burnt lime will be deficient and more sinter will be needed. To meet with these situations, the authors modified the charging equipment and ignition furnace at Kwangyang No. 2 sinter plant in April 1995. After the modification of the charging equipment and ignition furnace, the consumption of burnt lime and coke oven gas could be decreased and the sinter productivity increased in spite of the reduction of burnt lime consumption. This report describes the operation results with the modification of the charging equipment and ignition furnace in No. 2 sinter plant Kwangyang works.

  16. DRIVE CYCLE EFFICIENCY AND EMISSIONS ESTIMATES FOR REACTIVITY CONTROLLED COMPRESSION IGNITION IN A MULTI-CYLINDER LIGHT-DUTY DIESEL ENGINE

    SciTech Connect (OSTI)

    Curran, Scott; Briggs, Thomas E; Cho, Kukwon; Wagner, Robert M

    2011-01-01

    In-cylinder blending of gasoline and diesel to achieve Reactivity Controlled Compression Ignition (RCCI) has been shown to reduce NOx and PM emissions while maintaining or improving brake thermal efficiency as compared to conventional diesel combustion (CDC). The RCCI concept has an advantage over many advanced combustion strategies in that by varying both the percent of premixed gasoline and EGR rate, stable combustion can be extended over more of the light-duty drive cycle load range. Changing the percent premixed gasoline changes the fuel reactivity stratification in the cylinder providing further control of combustion phasing and pressure rise rate than the use of EGR alone. This paper examines the combustion and emissions performance of light-duty diesel engine using direct injected diesel fuel and port injected gasoline to carry out RCCI for steady-state engine conditions which are consistent with a light-duty drive cycle. A GM 1.9L four-cylinder engine with the stock compression ratio of 17.5:1, common rail diesel injection system, high-pressure EGR system and variable geometry turbocharger was modified to allow for port fuel injection with gasoline. Engine-out emissions, engine performance and combustion behavior for RCCI operation is compared against both CDC and a premixed charge compression ignition (PCCI) strategy which relies on high levels of EGR dilution. The effect of percent of premixed gasoline, EGR rate, boost level, intake mixture temperature, combustion phasing and pressure rise rate is investigated for RCCI combustion for the light-duty modal points. Engine-out emissions of NOx and PM were found to be considerably lower for RCCI operation as compared to CDC and PCCI, while HC and CO emissions were higher. Brake thermal efficiency was similar or higher for many of the modal conditions for RCCI operation. The emissions results are used to estimate hot-start FTP-75 emissions levels with RCCI and are compared against CDC and PCCI modes.

  17. Demonstration of a 13 keV Kr K-shell X-Ray Source at the National Ignition

    Office of Scientific and Technical Information (OSTI)

    Facility (Journal Article) | SciTech Connect Journal Article: Demonstration of a 13 keV Kr K-shell X-Ray Source at the National Ignition Facility Citation Details In-Document Search Title: Demonstration of a 13 keV Kr K-shell X-Ray Source at the National Ignition Facility Authors: Fournier, K B ; May, M J ; Colvin, J D ; Barrios, M A ; Patterson, J R ; Regan, S P Publication Date: 2013-05-29 OSTI Identifier: 1095970 Report Number(s): LLNL-JRNL-638276 DOE Contract Number: W-7405-ENG-48

  18. Experimental and Kinetic Modeling Study of Extinction and Ignition of Methyl Decanoate in Laminar Nonpremixed Flows

    SciTech Connect (OSTI)

    Seshadri, K; Lu, T; Herbinet, O; Humer, S; Niemann, U; Pitz, W J; Law, C K

    2008-01-09

    Methyl decanoate is a large methyl ester that can be used as a surrogate for biodiesel. In this experimental and computational study, the combustion of methyl decanoate is investigated in nonpremixed, nonuniform flows. Experiments are performed employing the counterflow configuration with a fuel stream made up of vaporized methyl decanoate and nitrogen, and an oxidizer stream of air. The mass fraction of fuel in the fuel stream is measured as a function of the strain rate at extinction, and critical conditions of ignition are measured in terms of the temperature of the oxidizer stream as a function of the strain rate. It is not possible to use a fully detailed mechanism for methyl decanoate to simulate the counterflow flames because the number of species and reactions is too large to employ with current flame codes and computer resources. Therefore a skeletal mechanism was deduced from a detailed mechanism of 8555 elementary reactions and 3036 species using 'directed relation graph' method. This skeletal mechanism has only 713 elementary reactions and 125 species. Critical conditions of ignition were calculated using this skeletal mechanism and are found to agree well with experimental data. The predicted strain rate at extinction is found to be lower than the measurements. In general, the methyl decanoate mechanism provides a realistic kinetic tool for simulation of biodiesel fuels.

  19. Hydrodynamic instability growth and mix experiments at the National Ignition Facility

    SciTech Connect (OSTI)

    Smalyuk, V. A.; Barrios, M.; Caggiano, J. A.; Casey, D. T.; Cerjan, C. J.; Clark, D. S.; Edwards, M. J.; Haan, S. W.; Hammel, B. A.; Hamza, A.; Hsing, W. W.; Hurricane, O.; Kroll, J.; Landen, O. L.; Lindl, J. D.; Ma, T.; McNaney, J. M.; Mintz, M.; Parham, T.; Peterson, J. L.; and others

    2014-05-15

    Hydrodynamic instability growth and its effects on implosion performance were studied at the National Ignition Facility [G. H. Miller, E. I. Moses, and C. R. Wuest, Opt. Eng. 443, 2841 (2004)]. Implosion performance and mix have been measured at peak compression using plastic shells filled with tritium gas and containing embedded localized carbon-deuterium diagnostic layers in various locations in the ablator. Neutron yield and ion temperature of the deuterium-tritium fusion reactions were used as a measure of shell-gas mix, while neutron yield of the tritium-tritium fusion reaction was used as a measure of implosion performance. The results have indicated that the low-mode hydrodynamic instabilities due to surface roughness were the primary culprits for yield degradation, with atomic ablator-gas mix playing a secondary role. In addition, spherical shells with pre-imposed 2D modulations were used to measure instability growth in the acceleration phase of the implosions. The capsules were imploded using ignition-relevant laser pulses, and ablation-front modulation growth was measured using x-ray radiography for a shell convergence ratio of ?2. The measured growth was in good agreement with that predicted, thus validating simulations for the fastest growing modulations with mode numbers up to 90 in the acceleration phase. Future experiments will be focused on measurements at higher convergence, higher-mode number modulations, and growth occurring during the deceleration phase.

  20. Shock tube ignition of ethanol, isobutene and MTBE: Experiments and modeling

    SciTech Connect (OSTI)

    Curran, H.J.; Dunphy, M.P.; Simmie, J.M.; Westbrook, C.K.; Pitz, W.J.

    1991-11-22

    The ignition of ethanol, isobutene and methyl tert-butyl ether (MTBE) has been studied experimentally in a shock tube and computationally with a detailed chemical kinetic model. Experimental results, consisting of ignition delay measurements, were obtained for a range of fuel/oxygen mixtures diluted in Argon, with temperatures varying over a range of 1100--1900 K. The numerical model consisted of a detailed kinetic reaction mechanism with more than 400 elementary reactions, chosen to describe reactions of each fuel and the smaller hydrocarbon and other species produced during their oxidation. The overall agreement between experimental and computed results was excellent, particularly for mixtures with greater than 0.3% fuel. The greatest sensitivity in the computed results was found to falloff parameters in the dissociation reactions of isobutene, ethane, methane, and ethyl and vinyl radicals, to the C{sub 3}H{sub 4} and C{sub 3}H{sub 5} reaction submechanisms in the model, and to the reactions in the H{sub 2}-O{sub 2}-Co submechanism.

  1. Vehicle Technologies Office Merit Review 2015: High Efficiency GDI Engine Research, with Emphasis on Ignition Systems

    Broader source: Energy.gov [DOE]

    Presentation given by Argonne National Laboratory at 2015 DOE Hydrogen and Fuel Cells Program and Vehicle Technologies Office Annual Merit Review and Peer Evaluation Meeting about high efficiency...

  2. design a high-resolution diagnostic system for the National Ignition...

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    laboratory conditions that produce similar extreme states of matter. The spectrometer for NIF will be the second for high-energy-density physics that Hill and Bitter have designed....

  3. Vehicle Technologies Office Merit Review 2014: High Efficiency GDI Engine Research, with Emphasis on Ignition Systems

    Broader source: Energy.gov [DOE]

    Presentation given by Argonne National Laboratory at 2014 DOE Hydrogen and Fuel Cells Program and Vehicle Technologies Office Annual Merit Review and Peer Evaluation Meeting about high efficiency...

  4. Application of Hydrogen Assisted Lean Operation to Natural Gas-Fueled Reciprocating Engines (HALO)

    SciTech Connect (OSTI)

    Chad Smutzer

    2006-01-01

    Two key challenges facing Natural Gas Engines used for cogeneration purposes are spark plug life and high NOx emissions. Using Hydrogen Assisted Lean Operation (HALO), these two keys issues are simultaneously addressed. HALO operation, as demonstrated in this project, allows stable engine operation to be achieved at ultra-lean (relative air/fuel ratios of 2) conditions, which virtually eliminates NOx production. NOx values of 10 ppm (0.07 g/bhp-hr NO) for 8% (LHV H2/LHV CH4) supplementation at an exhaust O2 level of 10% were demonstrated, which is a 98% NOx emissions reduction compared to the leanest unsupplemented operating condition. Spark ignition energy reduction (which will increase ignition system life) was carried out at an oxygen level of 9%, leading to a NOx emission level of 28 ppm (0.13 g/bhp-hr NO). The spark ignition energy reduction testing found that spark energy could be reduced 22% (from 151 mJ supplied to the coil) with 13% (LHV H2/LHV CH4) hydrogen supplementation, and even further reduced 27% with 17% hydrogen supplementation, with no reportable effect on NOx emissions for these conditions and with stable engine torque output. Another important result is that the combustion duration was shown to be only a function of hydrogen supplementation, not a function of ignition energy (until the ignitability limit was reached). The next logical step leading from these promising results is to see how much the spark energy reduction translates into increase in spark plug life, which may be accomplished by durability testing.

  5. Ablation driven by hot electrons generated during the ignitor laser pulse in shock ignition

    SciTech Connect (OSTI)

    Piriz, A. R.; Rodriguez Prieto, G. [E.T.S.I. Industriales, Universidad de Castilla-La Mancha and Instituto de Investigaciones Energeticas, 13071 Ciudad Real (Spain); Tahir, N. A. [GSI Helmholtzzentrum fuer Schwerionenforschung, Planckstrasse 1, 64291 Darmstadt (Germany); Zhang, Y. [School of Physics and Optoelectronic Technology, Dalian University of Technology, 116024 Dalian (China); Liu, S. D.; Zhao, Y. T. [Institute of Modern Physics, Chinese Academy of Science, 730000 Lanzhou (China)

    2012-12-15

    An analytical model for the ablation driven by hot electrons is presented. The hot electrons are assumed to be generated during the high intensity laser spike used to produce the ignitor shock wave in the shock ignition driven inertial fusion concept, and to carry on the absorbed laser energy in its totality. Efficient energy coupling requires to keep the critical surface sufficiently close to the ablation front and this goal can be achieved for high laser intensities provided that the laser wavelength is short enough. Scaling laws for the ablation pressure and the other relevant magnitudes of the ablation cloud are found in terms of the laser and target parameters. The effect of the preformed plasma assembled by the compression pulse, previous to the ignitor, is also discussed. It is found that a minimum ratio between the compression and the ignitor pulses would be necessary for the adequate matching of the corresponding scale lengths.

  6. A soft x-ray transmission grating imaging-spectrometer for the National Ignition Facility

    SciTech Connect (OSTI)

    Moore, A S; Guymer, T M; Kline, J L; Morton, J; Taccetti, M; Lanier, N E; Bentley, C; Workman, J; Peterson, B; Mussack, K; Cowan, J; Prasad, R; Richardson, M; Burns, S; Kalantar, D H; Benedetti, L R; Bell, P; Bradley, D; Hsing, W; Stevenson, M

    2012-05-01

    A soft x-ray transmission grating spectrometer has been designed for use on high energy-density physics experiments at the National Ignition Facility (NIF); coupled to one of the NIF gated x-ray detectors (GXD) it records sixteen time-gated spectra between 250 and 1000eV with 100ps temporal resolution. The trade-off between spectral and spatial resolution leads to an optimized design for measurement of emission around the peak of a 100-300eV blackbody spectrum. Performance qualification results from the NIF, the Trident Laser Facility and VUV beamline at the National Synchrotron Light Source (NSLS), evidence a <100{micro}m spatial resolution in combination with a source-size limited spectral resolution that is <10eV at photon energies of 300eV.

  7. Laser irradiance scaling in polar direct drive implosions on the National Ignition Facility

    SciTech Connect (OSTI)

    Murphy, T. J.; Krasheninnikova, N. S.; Kyrala, G. A.; Bradley, P. A.; Baumgaertel, J. A.; Cobble, J. A.; Hakel, P.; Hsu, S. C.; Kline, J. L.; Montgomery, D. S.; Obrey, K. A. D.; Shah, R. C.; Tregillis, I. L.; Schmitt, M. J.; Kanzleiter, R. J.; Batha, S. H.; Wallace, R. J.; Bhandarkar, S. D.; Fitzsimmons, P.; Hoppe, M. L.; Nikroo, A.; Hohenberger, M.; McKenty, P. W.; Rinderknecht, H. G.; Rosenberg, M. J.; Petrasso, R. D.

    2015-09-17

    Polar-direct-drive experiments conducted at the National Ignition Facility [E. I. Moses, Fusion Sci. Technol. 54, 361 (2008)] performed at laser irradiance between 1 and 2×1015 W/cm2 exhibit increased hard x-ray emission, decreased neutron yield, and reduced areal density as the irradiance is increased. Experimental x-ray images at the higher irradiances show x-ray emission at the equator, as well as degraded symmetry, that is not predicted in hydrodynamic simulations using flux-limited energy transport, but that appear when non-local electron transport together with a model to account for cross beam energy transfer (CBET) is utilized. The reduction in laser power for equatorial beams required in the simulations to reproduce the effects of CBET on the observed symmetry also reproduces the yield degradation consistent with experimental data.

  8. A High-Resolution Integrated Model of the National Ignition Campaign Cryogenic Layered Experiments

    DOE Public Access Gateway for Energy & Science Beta (PAGES Beta)

    Jones, O. S.; Callahan, D. A.; Cerjan, C. J.; Clark, D. S.; Dixit, S. M.; Dopppner, T.; Dylla-Spears, R. J.; Dzentitis, E. G.; Farley, D. R.; Glenn, S. M.; et al

    2012-05-29

    A detailed simulation-based model of the June 2011 National Ignition Campaign (NIC) cryogenic DT experiments is presented. The model is based on integrated hohlraum-capsule simulations that utilize the best available models for the hohlraum wall, ablator, and DT equations of state and opacities. The calculated radiation drive was adjusted by changing the input laser power to match the experimentally measured shock speeds, shock merger times, peak implosion velocity, and bangtime. The crossbeam energy transfer model was tuned to match the measured time-dependent symmetry. Mid-mode mix was included by directly modeling the ablator and ice surface perturbations up to mode 60.more »Simulated experimental values were extracted from the simulation and compared against the experiment. The model adjustments brought much of the simulated data into closer agreement with the experiment, with the notable exception of the measured yields, which were 15-40% of the calculated yields.« less

  9. Laser irradiance scaling in polar direct drive implosions on the National Ignition Facility

    DOE Public Access Gateway for Energy & Science Beta (PAGES Beta)

    Murphy, T. J.; Krasheninnikova, N. S.; Kyrala, G. A.; Bradley, P. A.; Baumgaertel, J. A.; Cobble, J. A.; Hakel, P.; Hsu, S. C.; Kline, J. L.; Montgomery, D. S.; et al

    2015-09-17

    Polar-direct-drive experiments conducted at the National Ignition Facility [E. I. Moses, Fusion Sci. Technol. 54, 361 (2008)] performed at laser irradiance between 1 and 2×1015 W/cm2 exhibit increased hard x-ray emission, decreased neutron yield, and reduced areal density as the irradiance is increased. Experimental x-ray images at the higher irradiances show x-ray emission at the equator, as well as degraded symmetry, that is not predicted in hydrodynamic simulations using flux-limited energy transport, but that appear when non-local electron transport together with a model to account for cross beam energy transfer (CBET) is utilized. The reduction in laser power for equatorialmore » beams required in the simulations to reproduce the effects of CBET on the observed symmetry also reproduces the yield degradation consistent with experimental data.« less

  10. DIESEL OXIDATION CATALYST CONTROL OF HYDROCARBON AEROSOLS FROM REACTIVITY CONTROLLED COMPRESSION IGNITION COMBUSTION

    SciTech Connect (OSTI)

    Prikhodko, Vitaly Y; Parks, II, James E; Barone, Teresa L; Curran, Scott; Cho, Kukwon; Lewis Sr, Samuel Arthur; Storey, John Morse; Wagner, Robert M

    2011-01-01

    Reactivity Controlled Compression Ignition (RCCI) is a novel combustion process that utilizes two fuels with different reactivity to stage and control combustion and enable homogeneous combustion. The technique has been proven experimentally in previous work with diesel and gasoline fuels; low NOx emissions and high efficiencies were observed from RCCI in comparison to conventional combustion. In previous studies on a multi-cylinder engine, particulate matter (PM) emission measurements from RCCI suggested that hydrocarbons were a major component of the PM mass. Further studies were conducted on this multi-cylinder engine platform to characterize the PM emissions in more detail and understand the effect of a diesel oxidation catalyst (DOC) on the hydrocarbon-dominated PM emissions. Results from the study show that the DOC can effectively reduce the hydrocarbon emissions as well as the overall PM from RCCI combustion. The bimodal size distribution of PM from RCCI is altered by the DOC which reduces the smaller mode 10 nm size particles.

  11. The National Ignition Facility: Ushering in a new age for high energy density science

    SciTech Connect (OSTI)

    Moses, E. I.; Boyd, R. N.; Remington, B. A.; Keane, C. J.; Al-Ayat, R.

    2009-04-15

    The National Ignition Facility (NIF) [E. I. Moses, J. Phys.: Conf. Ser. 112, 012003 (2008); https://lasers.llnl.gov/], completed in March 2009, is the highest energy laser ever constructed. The high temperatures and densities achievable at NIF will enable a number of experiments in inertial confinement fusion and stockpile stewardship, as well as access to new regimes in a variety of experiments relevant to x-ray astronomy, laser-plasma interactions, hydrodynamic instabilities, nuclear astrophysics, and planetary science. The experiments will impact research on black holes and other accreting objects, the understanding of stellar evolution and explosions, nuclear reactions in dense plasmas relevant to stellar nucleosynthesis, properties of warm dense matter in planetary interiors, molecular cloud dynamics and star formation, and fusion energy generation.

  12. PLANNING TOOLS FOR ESTIMATING RADIATION EXPOSURE AT THE NATIONAL IGNITION FACILITY

    SciTech Connect (OSTI)

    Verbeke, J; Young, M; Brereton, S; Dauffy, L; Hall, J; Hansen, L; Khater, H; Kim, S; Pohl, B; Sitaraman, S

    2010-10-22

    A set of computational tools was developed to help estimate and minimize potential radiation exposure to workers from material activation in the National Ignition Facility (NIF). AAMI (Automated ALARA-MCNP Interface) provides an efficient, automated mechanism to perform the series of calculations required to create dose rate maps for the entire facility with minimal manual user input. NEET (NIF Exposure Estimation Tool) is a web application that combines the information computed by AAMI with a given shot schedule to compute and display the dose rate maps as a function of time. AAMI and NEET are currently used as work planning tools to determine stay-out times for workers following a given shot or set of shots, and to help in estimating integrated doses associated with performing various maintenance activities inside the target bay. Dose rate maps of the target bay were generated following a low-yield 10{sup 16} D-T shot and will be presented in this paper.

  13. Radiation transport and energetics of laser-driven half-hohlraums at the National Ignition Facility

    SciTech Connect (OSTI)

    Moore, A. S. [Directorate Science and Technology, AWE Aldermaston, Reading (United Kingdom); Cooper, A. B.R. [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States); Schneider, M. B. [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States); MacLaren, S. [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States); Graham, P. [Directorate Science and Technology, AWE Aldermaston, Reading (United Kingdom); Lu, K. [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States); Seugling, R. [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States); Satcher, J. [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States); Klingmann, J. [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States); Comley, A. J. [Directorate Science and Technology, AWE Aldermaston, Reading (United Kingdom); Marrs, R. [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States); May, M. [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States); Widmann, K. [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States); Glendinning, G. [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States); Castor, J. [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States); Sain, J. [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States); Back, C. A. [General Atomics, San Diego, CA (United States); Hund, J. [General Atomics, San Diego, CA (United States); Baker, K. [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States); Hsing, W. W. [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States); Foster, J. [Directorate Science and Technology, AWE Aldermaston, Reading (United Kingdom); Young, B. [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States); Young, P. [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States)

    2014-06-01

    Experiments that characterize and develop a high energy-density half-hohlraum platform for use in bench-marking radiation hydrodynamics models have been conducted at the National Ignition Facility (NIF). Results from the experiments are used to quantitatively compare with simulations of the radiation transported through an evolving plasma density structure, colloquially known as an N-wave. A half-hohlraum is heated by 80 NIF beams to a temperature of 240 eV. This creates a subsonic di#11;usive Marshak wave which propagates into a high atomic number Ta2O5 aerogel. The subsequent radiation transport through the aerogel and through slots cut into the aerogel layer is investigated. We describe a set of experiments that test the hohlraum performance and report on a range

  14. X-ray area backlighter development at the National Ignition Facility (invited)

    SciTech Connect (OSTI)

    Barrios, M. A. Fournier, K. B.; Smith, R.; Lazicki, A.; Rygg, R.; Fratanduono, D. E.; Eggert, J.; Park, H.-S.; Huntington, C.; Bradley, D. K.; Landen, O. L.; Collins, G. W.; Regan, S. P.; Epstein, R.

    2014-11-15

    1D spectral imaging was used to characterize the K-shell emission of Z ? 3035 and Z ? 4042 laser-irradiated foils at the National Ignition Facility. Foils were driven with up to 60 kJ of 3? light, reaching laser irradiances on target between 0.5 and 20 10{sup 15} W/cm{sup 2}. Laser-to-X-ray conversion efficiency (CE) into the He{sub ?} line (plus satellite emission) of 1.0%1.5% and 0.15%0.2% was measured for Z ? 3032 and Z ? 4042, respectively. Measured CE into He{sub ?} (plus satellite emission) of Br (Z = 35) compound foils (either KBr or RbBr) ranged between 0.16% and 0.29%. Measured spectra are compared with 1D non-local thermodynamic equilibrium atomic kinetic and radiation transport simulations, providing a fast and accurate predictive capability.

  15. Kinetics of ignition of saturated hydrocarbons by nonequilibrium plasma: C{sub 2}H{sub 6} -to C{sub 5}H{sub 12}-containing mixtures

    SciTech Connect (OSTI)

    Kosareva, I.N.; Aleksandrova, N.L.; Kindyshevaa, S.V.; Starikovskaia, S.M.; Starikovskii, A.Yu.

    2009-01-15

    The kinetics of ignition in C{sub n}H{sub 2n+2}:O{sub 2}:Ar mixtures for n=2 to 5 has been studied experimentally and numerically after a high-voltage nanosecond discharge. The ignition delay time behind a reflected shock wave was measured with and without the discharge. It was shown that the initiation of the discharge with a specific deposited energy of 10-30 mJ/cm{sup 3} leads to an order of magnitude decrease in the ignition delay time. Discharge processes and following chain chemical reactions with energy release were simulated. The generation of atoms, radicals and excited and charged particles was numerically simulated using the measured time-resolved discharge current and electric field in the discharge phase. The calculated densities of the active particles were used as input data to simulate plasma-assisted ignition. The sensitivity of the results to variation in electron cross sections, reaction rates and radical composition was investigated. Good agreement was obtained between the calculated ignition delay times and the experimental data. The analysis of the simulation results showed that the effect of nonequilibrium plasma on the ignition delay is associated with faster development of chain reactions, due to atoms and radicals produced by the electron impact dissociation of molecules in the discharge phase. Finally, we studied the role of various hydrocarbon radicals in the plasma-assisted ignition of the mixtures under consideration. (author)

  16. Ion Fast Ignition-Establishing a Scientific Basis for Inertial Fusion Energy --- Final Report

    SciTech Connect (OSTI)

    Stephens, Richard Burnite; Foord, Mark N.; Wei, Mingsheng; Beg, Farhat N.; Schumacher, Douglass W.

    2013-10-31

    The Fast Ignition (FI) Concept for Inertial Confinement Fusion (ICF) has the potential to provide a significant advance in the technical attractiveness of Inertial Fusion Energy reactors. FI differs from conventional ?central hot spot? (CHS) target ignition by decoupling compression from heating: using a laser (or heavy ion beam or Z pinch) drive pulse (10?s of nanoseconds) to create a dense fuel and a second, much shorter (~10 picoseconds) high intensity pulse to ignite a small volume within the dense fuel. The compressed fuel is opaque to laser light. The ignition laser energy must be converted to a jet of energetic charged particles to deposit energy in the dense fuel. The original concept called for a spray of laser-generated hot electrons to deliver the energy; lack of ability to focus the electrons put great weight on minimizing the electron path. An alternative concept, proton-ignited FI, used those electrons as intermediaries to create a jet of protons that could be focused to the ignition spot from a more convenient distance. Our program focused on the generation and directing of the proton jet, and its transport toward the fuel, none of which were well understood at the onset of our program. We have developed new experimental platforms, diagnostic packages, computer modeling analyses, and taken advantage of the increasing energy available at laser facilities to create a self-consistent understanding of the fundamental physics underlying these issues. Our strategy was to examine the new physics emerging as we added the complexity necessary to use proton beams in an inertial fusion energy (IFE) application. From the starting point of a proton beam accelerated from a flat, isolated foil, we 1) curved it to focus the beam, 2) attached the foil to a superstructure, 3) added a side sheath to protect it from the surrounding plasma, and finally 4) studied the proton beam behavior as it passed through a protective end cap into plasma. We built up, as we proceeded, a self-consistent picture of the quasi-neutral plasma jet that is the proton beam that, for the first time, included the role of the hot electrons in shaping the jet. Controlling them?through design of the accelerating surface and its connection to the surrounding superstructure?is critical; their uniform spread across the proton accelerating area is vital, but their presence in the jet opposes focus; their electron flow away from the acceleration area reduces conversion efficiency but can also increase focusing ability. The understanding emerging from our work and the improved simulation tools we have developed allow designing structures that optimize proton beams for focused heating. Our findings include: ? The achievable focus of proton beams is limited by the thermal pressure gradient in the laser-generated hot electrons that drive the process. This bending can be suppressed using a controlled flow of hot electrons along the surrounding cone wall, which induces a local transverse focusing sheath electric field. The resultant (vacuum-focused) spot can meet IFE requirements. ? Confinement of laser-generated electrons to the proton accelerating area can be achieved by supporting targets on thin struts. That increases laser-to-proton conversion energy by ~50%. As noted above, confinement should not be total; necessary hot-electron leakage into the surrounding superstructure for proton focusing can be controlled by with the strut width/number. ? Proton jets are further modified as they enter the fuel through the superstructure?s end cap. They can generate currents during that transit that further focus the proton beams. We developed a new ion stopping module for LSP code that properly accounted for changes in stopping power with ionization (e.g. temperature), and will be using it in future studies. The improved understanding, new experimental platforms, and the self-consistent modeling capability allow researchers a new ability to investigate the interaction of large ion currents with warm dense matter. That is of direct importance to the creation and investiga

  17. Air separation membranes : an alternative to EGR in large bore natural gas engines.

    SciTech Connect (OSTI)

    Biruduganti, M.; Gupta, S.; Bihari, B.; McConnell, S.; Sekar, R.; Energy Systems

    2010-08-01

    Air separation membranes (ASMs) could potentially replace exhaust gas recirculation (EGR) technology in engines due to the proven benefits in NOx reduction but without the drawbacks of EGR. Previous investigations of nitrogen-enriched air (NEA) combustion using nitrogen bottles showed up to 70% NOx reduction with modest 2% nitrogen enrichment. The investigation in this paper was performed with an ASM capable of delivering at least 3.5% NEA to a single-cylinder spark-ignited natural gas engine. Low temperature combustion is one of the pathways to meet the mandatory ultra low NOx emissions levels set by regulatory agencies. In this study, a comparative assessment is made between natural gas combustion in standard air and 2% NEA. Enrichment beyond this level degraded engine performance in terms of power density, brake thermal efficiency (BTE), and unburned hydrocarbon emissions for a given equivalence ratio. The ignition timing was optimized to yield maximum brake torque for standard air and NEA. Subsequently, conventional spark ignition was replaced by laser ignition (LI) to extend lean ignition limit. Both ignition systems were studied under a wide operating range from {Psi} :1.0 to the lean misfire limit. It was observed that with 2% NEA, for a similar fuel quantity, the equivalence ratio {Psi} increases by 0.1 relative to standard air conditions. Analysis showed that lean burn operation along with NEA and alternative ignition source, such as LI, could pave the pathway for realizing lower NO{sub x} emissions with a slight penalty in BTE.

  18. Pulse combustor with controllable oscillations

    DOE Patents [OSTI]

    Richards, George A. (Morgantown, WV); Welter, Michael J. (Columbiana, OH); Morris, Gary J. (Morgantown, WV)

    1992-01-01

    A pulse combustor having thermally induced pulse combustion in a continuously flowing system is described. The pulse combustor is fitted with at lease one elongated ceramic body which significantly increases the heat transfer area in the combustion chamber of the combustor. The ceramic body or bodies possess sufficient mass and heat capacity to ignite the fuel-air charge once the ceramic body or bodies are heated by conventional spark plug initiated combustion so as to provide repetitive ignition and combustion of sequentially introduced fuel-air charges without the assistance of the spark plug and the rapid quenching of the flame after each ignition in a controlled manner so as to provide a selective control over the oscillation frequency and amplitude. Additional control over the heat transfer in the combustion chamber is provided by employing heat exchange mechanisms for selectively heating or cooling the elongated ceramic body or bodies and/or the walls of the combustion chamber.

  19. Method and system for controlled combustion engines

    DOE Patents [OSTI]

    Oppenheim, A. K. (Berkeley, CA)

    1990-01-01

    A system for controlling combustion in internal combustion engines of both the Diesel or Otto type, which relies on establishing fluid dynamic conditions and structures wherein fuel and air are entrained, mixed and caused to be ignited in the interior of a multiplicity of eddies, and where these structures are caused to sequentially fill the headspace of the cylinders.

  20. Performance of High-Convergence, Layered DT Implosions on Power-Scaling Experiments at National Ignition Facility

    SciTech Connect (OSTI)

    Smalyuk, V. A.; Atherton, L. J.; Benedetti, L. R.; Bionta, R.; Bleuel, D.; Bond, E.; Bradley, D. K.; Caggiano, J.; Callahan, D. A.; Casey, D. T.; Celliers, P. M.; Cerjan, C. J.; Clark, D.; Dewald, E. L.; Dixit, S. N.; Doeppner, T.; Edgell, D. H.; Edwards, M. J.; Frenje, J.; Gatu-Johnson, M.; Glebov, V. Y.; Glenn, S.; Glenzer, S. H.; Grim, G.; Haan, S. W.; Hammel, B. A.; Hartouni, E.; Hatarik, R.; Hatchett, S.; Hicks, D.; Hsing, W. W.; Izumi, N.; Jones, O. S.; Key, M. H.; Khan, S. F.; Kilkenny, J. D.; Kline, J. L.; Knauer, J.; Kyrala, G. A.; Landen, O. L.; Pape, S. L.; Lindl, J. D.; Ma, T.; MacGowan, B. J.; Mackinnon, A. J.; MacPhee, A. G.; McNaney, J.; Meezan, N. B.; Moody, J. D.; Moore, A.; Moran, M.; Moses, E. I.; Pak, A.; Parham, T; Park, H. -S.; Patel, P. K.; Petrasso, R.; Ralph, J. E.; Regan, S. P.; Remington, B. A.; Robey, H. F.; Ross, J. S.; Spears, B. K.; Springer, P. T.; Suter, L J; Tommasini, R.; Town, R. P.; Weber, S. V.; Widmann, K.

    2013-10-19

    The radiation-driven, low-adiabat, cryogenic DT layered plastic capsule implosions were carried out on the National Ignition Facility (NIF) to study the sensitivity of performance to peak power and drive duration. An implosion with extended drive and at reduced peak power of 350 TW achieved the highest compression with fuel areal density of ~1.3±0.1 g/cm 2, representing a significant step from previously measured ~1.0 g/cm2 toward a goal of 1.5 g/cm 2. Moreover, for future experiments will focus on understanding and mitigating hydrodynamic instabilities and mix, and improving symmetry required to reach the threshold for thermonuclear ignition on NIF.

  1. Performance of High-Convergence, Layered DT Implosions on Power-Scaling Experiments at National Ignition Facility

    DOE Public Access Gateway for Energy & Science Beta (PAGES Beta)

    Smalyuk, V. A.; Atherton, L. J.; Benedetti, L. R.; Bionta, R.; Bleuel, D.; Bond, E.; Bradley, D. K.; Caggiano, J.; Callahan, D. A.; Casey, D. T.; et al

    2013-10-19

    The radiation-driven, low-adiabat, cryogenic DT layered plastic capsule implosions were carried out on the National Ignition Facility (NIF) to study the sensitivity of performance to peak power and drive duration. An implosion with extended drive and at reduced peak power of 350 TW achieved the highest compression with fuel areal density of ~1.3±0.1 g/cm 2, representing a significant step from previously measured ~1.0 g/cm2 toward a goal of 1.5 g/cm 2. Moreover, for future experiments will focus on understanding and mitigating hydrodynamic instabilities and mix, and improving symmetry required to reach the threshold for thermonuclear ignition on NIF.

  2. Cyclic Combustion Variations in Dual Fuel Partially Premixed Pilot-Ignited Natural Gas Engines

    SciTech Connect (OSTI)

    Srinivasan, K. K.; Krishnan, S. R.

    2012-05-09

    Dual fuel pilot ignited natural gas engines are identified as an efficient and viable alternative to conventional diesel engines. This paper examines cyclic combustion fluctuations in conventional dual fuel and in dual fuel partially premixed low temperature combustion (LTC). Conventional dual fueling with 95% (energy basis) natural gas (NG) substitution reduces NOx emissions by almost 90%t relative to straight diesel operation; however, this is accompanied by 98% increase in HC emissions, 10 percentage points reduction in fuel conversion efficiency (FCE) and 12 percentage points increase in COVimep. Dual fuel LTC is achieved by injection of a small amount of diesel fuel (2-3 percent on an energy basis) to ignite a premixed natural gas???????¢????????????????air mixture to attain very low NOx emissions (less than 0.2 g/kWh). Cyclic variations in both combustion modes were analyzed by observing the cyclic fluctuations in start of combustion (SOC), peak cylinder pressures (Pmax), combustion phasing (Ca50), and the separation between the diesel injection event and Ca50 (termed ???????¢????????????????relative combustion phasing???????¢???????????????). For conventional dual fueling, as % NG increases, Pmax decreases, SOC and Ca50 are delayed, and cyclic variations increase. For dual fuel LTC, as diesel injection timing is advanced from 20???????????????° to 60???????????????°BTDC, the relative combustion phasing is identified as an important combustion parameter along with SoC, Pmax, and CaPmax. For both combustion modes, cyclic variations were characterized by alternating slow and fast burn cycles, especially at high %NG and advanced injection timings. Finally, heat release return maps were analyzed to demonstrate thermal management strategies as an effective tool to mitigate cyclic combustion variations, especially in dual fuel LTC.

  3. A Study of Detonation Diffraction in the Ignition-and-Growth Model

    SciTech Connect (OSTI)

    Kapila, A K; Schwendeman, D W; Bdzil, J B; Henshaw, W D

    2006-04-14

    Heterogeneous high-energy explosives are morphologically, mechanically and chemically complex. As such, their ab-initio modeling, in which well-characterized phenomena at the scale of the microstructure lead to a rationally homogenized description at the scale of observation, is a subject of active research but not yet a reality. An alternative approach is to construct phenomenological models, in which forms of constitutive behavior are postulated with an eye on the perceived picture of the micro-scale phenomena, and which are strongly linked to experimental calibration. Most prominent among these is the ignition-and-growth model conceived by Lee and Tarver. The model treats the explosive as a homogeneous mixture of two distinct constituents, the unreacted explosive and the products of reaction. To each constituent is assigned an equation of state, and a single reaction-rate law is prescribed for the conversion of the explosive to products. It is assumed that the two constituents are always in pressure and temperature equilibrium. The purpose of this paper is to investigate in detail the behavior of the model in situations where a detonation turns a corner and undergoes diffraction. A set of parameters appropriate for the explosive LX-17 is selected. The model is first examined analytically for steady, planar, 1-D solutions and the reaction-zone structure of Chapman-Jouguet detonations is determined. A computational study of two classes of problems is then undertaken. The first class corresponds to planar, 1-D initiation by an impact, and the second to corner turning and diffraction in planar and axisymmetric geometries. The 1-D initiation, although interesting in its own right, is utilized here as a means for interpretation of the 2-D results. It is found that there are two generic ways in which 1-D detonations are initiated in the model, and that these scenarios play a part in the post-diffraction evolution as well. For the parameter set under study the model shows detonation failure, but only locally and temporarily, and does not generate sustained dead zones. The computations employ adaptive mesh refinement and are finely resolved. Results are obtained for a rigid confinement of the explosive. Compliant confinement represents its own computational challenges and is currently under study. Also under development is an extended ignition-and-growth model which takes into account observed desensitization of heterogeneous explosives by weak shocks.

  4. Analysis of ignition behavior in a turbocharged direct injection dual fuel engine using propane and methane as primary fuels

    SciTech Connect (OSTI)

    Polk, A. C.; Gibson, C. M.; Shoemaker, N. T.; Srinivasan, K. K.; Krishnan, S. R.

    2011-10-05

    This paper presents experimental analyses of the ignition delay (ID) behavior for diesel-ignited propane and diesel-ignited methane dual fuel combustion. Two sets of experiments were performed at a constant speed (1800 rev/min) using a 4-cylinder direct injection diesel engine with the stock ECU and a wastegated turbocharger. First, the effects of fuel-air equivalence ratios (Ω pilot ∼ 0.2-0.6 and Ω overall ∼ 0.2-0.9) on IDs were quantified. Second, the effects of gaseous fuel percent energy substitution (PES) and brake mean effective pressure (BMEP) (from 2.5 to 10 bar) on IDs were investigated. With constant Ω pilot (> 0.5), increasing Ω overall with propane initially decreased ID but eventually led to premature propane autoignition; however, the corresponding effects with methane were relatively minor. Cyclic variations in the start of combustion (SOC) increased with increasing Ω overall (at constant Ω pilot), more significantly for propane than for methane. With increasing PES at constant BMEP, the ID showed a nonlinear (initially increasing and later decreasing) trend at low BMEPs for propane but a linearly decreasing trend at high BMEPs. For methane, increasing PES only increased IDs at all BMEPs. At low BMEPs, increasing PES led to significantly higher cyclic SOC variations and SOC advancement for both propane and methane. Finally, the engine ignition delay (EID) was also shown to be a useful metric to understand the influence of ID on dual fuel combustion.

  5. An electron/ion spectrometer with the ability of low energy electron measurement for fast ignition experiments

    SciTech Connect (OSTI)

    Ozaki, T.; Sakagami, H. [National Institute for Fusion Science, 322-6, Oroshi, Toki, Gifu 509-5292 (Japan); Kojima, S.; Arikawa, Y.; Shiraga, H.; Fujioka, S. [Institute of Laser Engineering, Osaka University, 2-6, Yamada-oka, Suita, Osaka 565-0871 (Japan); Kato, R., E-mail: ozaki@nifs.ac.jp [Institute of Scientific and Industrial Research, Osaka University, 8-1, Mihogaoka, Ibaraki, Osaka 567-0047 (Japan)

    2014-11-15

    An electron energy spectrometer (ESM) is one of the most fundamental diagnostics in the fast ignition experiment. It is necessary to observe the spectra down to a low energy range in order to obtain the accurate deposition efficiency toward the core. Here, we realize the suitable ESM by using a ferrite magnet with a moderate magnetic field of 0.3 T and a rectangular magnetic circuit covered with a steel plate in the inlet side.

  6. Development of the CD Symcap platform to study gas-shell mix in implosions at the National Ignition Facility

    SciTech Connect (OSTI)

    Casey, D. T.; Smalyuk, V. A.; Tipton, R. E.; Pino, J. E.; Remington, B. A.; Rowley, D. P.; Weber, S. V.; Barrios, M.; Benedetti, L. R.; Bleuel, D. L.; Bond, E. J.; Bradley, D. K.; Caggiano, J. A.; Callahan, D. A.; Cerjan, C. J.; Edwards, M. J.; Fittinghoff, D.; Glenn, S.; Haan, S. W.; Hamza, A.; and others

    2014-09-15

    Surrogate implosions play an important role at the National Ignition Facility (NIF) for isolating aspects of the complex physical processes associated with fully integrated ignition experiments. The newly developed CD Symcap platform has been designed to study gas-shell mix in indirectly driven, pure T{sub 2}-gas filled CH-shell implosions equipped with 4 ?m thick CD layers. This configuration provides a direct nuclear signature of mix as the DT yield (above a characterized D contamination background) is produced by D from the CD layer in the shell, mixing into the T-gas core. The CD layer can be placed at different locations within the CH shell to probe the depth and extent of mix. CD layers placed flush with the gas-shell interface and recessed up to 8??m have shown that most of the mix occurs at the inner-shell surface. In addition, time-gated x-ray images of the hotspot show large brightly radiating objects traversing through the hotspot around bang-time, which are likely chunks of CH/CD plastic. This platform is a powerful new capability at the NIF for understanding mix, one of the key performance issues for ignition experiments.

  7. Development of the CD symcap platform to study gas-shell mix in implosions at the National Ignition Facility

    SciTech Connect (OSTI)

    Casey, D. T.; Smalyuk, V. A.; Tipton, R. E.; Pino, J. E.; Grim, G. P.; Remington, B. A.; Rowley, D. P.; Weber, S. V.; Barrios, M.; Benedetti, L. R.; Bleuel, D. L.; Bond, E. J.; Bradley, D. K.; Caggiano, J. A.; Callahan, D. A.; Cerjan, C. J.; Chen, K. C.; Edgell, D. H.; Edwards, M. J.; Fittinghoff, D.; Frenje, J. A.; Gatu-Johnson, M.; Glebov, V. Y.; Glenn, S.; Guler, N.; Haan, S. W.; Hamza, A.; Hatarik, R.; Herrmann, H. W.; Hoover, D.; Hsing, W. W.; Izumi, N.; Kervin, P.; Khan, S.; Kilkenny, J. D.; Kline, J.; Knauer, J.; Kyrala, G.; Landen, O. L.; Ma, T.; MacPhee, A. G.; McNaney, J. M.; Mintz, M.; Moore, A.; Nikroo, A.; Pak, A.; Parham, T.; Petrasso, R.; Rinderknecht, H. G.; Sayre, D. B.; Schneider, M.; Stoeffl, W.; Tommasini, R.; Town, R. P.; Widmann, K.; Wilson, D. C.; Yeamans, C. B.

    2014-09-09

    Surrogate implosions play an important role at the National Ignition Facility (NIF) for isolating aspects of the complex physical processes associated with fully integrated ignition experiments. The newly developed CD Symcap platform has been designed to study gas-shell mix in indirectly driven, pure T?-gas filled CH-shell implosions equipped with 4 ?m thick CD layers. This configuration provides a direct nuclear signature of mix as the DT yield (above a characterized D contamination background) is produced by D from the CD layer in the shell, mixing into the T-gas core. The CD layer can be placed at different locations within the CH shell to probe the depth and extent of mix. CD layers placed flush with the gas-shell interface and recessed up to 8 ?m have shown that most of the mix occurs at the inner-shell surface. In addition, time-gated x-ray images of the hotspot show large brightly-radiating objects traversing through the hotspot around bang-time, which are likely chunks of CH/CD plastic. This platform is a powerful new capability at the NIF for understanding mix, one of the key performance issues for ignition experiments.

  8. Development of the CD symcap platform to study gas-shell mix in implosions at the National Ignition Facility

    DOE Public Access Gateway for Energy & Science Beta (PAGES Beta)

    Casey, D. T.; Smalyuk, V. A.; Tipton, R. E.; Pino, J. E.; Grim, G. P.; Remington, B. A.; Rowley, D. P.; Weber, S. V.; Barrios, M.; Benedetti, L. R.; et al

    2014-09-09

    Surrogate implosions play an important role at the National Ignition Facility (NIF) for isolating aspects of the complex physical processes associated with fully integrated ignition experiments. The newly developed CD Symcap platform has been designed to study gas-shell mix in indirectly driven, pure T₂-gas filled CH-shell implosions equipped with 4 μm thick CD layers. This configuration provides a direct nuclear signature of mix as the DT yield (above a characterized D contamination background) is produced by D from the CD layer in the shell, mixing into the T-gas core. The CD layer can be placed at different locations within themore » CH shell to probe the depth and extent of mix. CD layers placed flush with the gas-shell interface and recessed up to 8 μm have shown that most of the mix occurs at the inner-shell surface. In addition, time-gated x-ray images of the hotspot show large brightly-radiating objects traversing through the hotspot around bang-time, which are likely chunks of CH/CD plastic. This platform is a powerful new capability at the NIF for understanding mix, one of the key performance issues for ignition experiments.« less

  9. Design of precision mounts for optimizing the conversion efficiency of KDP crystals for the National Ignition Facility

    SciTech Connect (OSTI)

    Hibbard, R.L., LLNL

    1998-03-30

    A key design challenge for the National Ignition Facility (NIF), being constructed at Lawrence Livermore National Laboratory (LLNL), [Hibbard, R L , 1998], is the frequency converter consisting of two KDP crystals and a focusing lens Frequency conversion is a critical performance factor for NIF and the optical mount design for this plays a key role in meeting design specifications The frequency converter is a monolithic cell that mounts the optics and is the point on the beamline where the frequency conversion crystals are optimally aligned and the cell is focused on target The lasing medium is neodymium in phosphate glass with a fundamental frequency (1{omega}) of 1 053 {micro}m Sum frequency generation in a pair of conversion crystals (KDP/KD*P) produces 1 8 MJ of the third harmonic light (3{omega} or {lambda}=O 35 pm). The phase-matching scheme on NIF is type I second harmonic generation followed by type II sum-frequency-mixing of the residual fundamental and the second harmonic light This laser unlike previous laser system designs, must achieve high conversion efficiency, 85%, which is close to the 90 8% theoretical maximum As a result, this design is very sensitive to angular variations in beam propagation and in the crystal axes orientation. Factors that influence the phase matching angle include crystal inhomogeneity, residual and induced stress in the crystals, the crystals` natural and mounted surface figure, mounting imperfections and gravity sag These angular variations need to be controlled within a 40 {micro}rad error budget. The optical mount contributions to the angular error budget are 20 {micro}rad and are what make the frequency converter in the Final Optics Cell (FOC) such a challenging precision design. The premise of using full edge support in the FOC design is primarily driven by the spherical target chamber design that has optics mounted at multiple longitudinal angles and thus gravity sag in the crystals that needs to be minimized To meet the angular performance requirements, a precision monolithic cell with full edge support for mounting the optics to 10 {micro}rad angular and 1-5 {micro}m flatness tolerances is required The NIF frequency converter design is a major step in improving both conversion efficiency and precision of the mount design Another major consideration in the FOC design is the trade-off between cost of manufacturing the cell and the performance of the mount An interesting balance of what can be accomplished with a conventional machine tool in a commercial shop to produce prototype FOC` s will be discussed Metrology issues involved in qualifying the FOC are also discussed.

  10. The effects of early time laser drive on hydrodynamic instability growth in National Ignition Facility implosions

    SciTech Connect (OSTI)

    Peterson, J. L.; Clark, D. S.; Suter, L. J.; Masse, L. P.

    2014-09-15

    Defects on inertial confinement fusion capsule surfaces can seed hydrodynamic instability growth and adversely affect capsule performance. The dynamics of shocks launched during the early period of x-ray driven National Ignition Facility (NIF) implosions determine whether perturbations will grow inward or outward at peak implosion velocity and final compression. In particular, the strength of the first shock, launched at the beginning of the laser pulse, plays an important role in determining Richtmyer-Meshkov (RM) oscillations on the ablation front. These surface oscillations can couple to the capsule interior through subsequent shocks before experiencing Rayleigh-Taylor (RT) growth. We compare radiation hydrodynamic simulations of NIF implosions to analytic theories of the ablative RM and RT instabilities to illustrate how early time laser strength can alter peak velocity growth. We develop a model that couples the RM and RT implosion phases and captures key features of full simulations. We also show how three key parameters can control the modal demarcation between outward and inward growth.

  11. Higher velocity, high-foot implosions on the National Ignition Facility laser

    SciTech Connect (OSTI)

    Callahan, D. A.; Hurricane, O. A.; Hinkel, D. E.; Dppner, T.; Ma, T.; Park, H.-S.; Barrios Garcia, M. A.; Berzak Hopkins, L. F.; Casey, D. T.; Cerjan, C. J.; Dewald, E. L.; Dittrich, T. R.; Edwards, M. J.; Haan, S. W.; Hamza, A. V.; Kritcher, A. L.; Landen, O. L.; LePape, S.; MacPhee, A. G.; Milovich, J. L.; and others

    2015-05-15

    By increasing the velocity in high foot implosions [Dittrich et al., Phys. Rev. Lett. 112, 055002 (2014); Park et al., Phys. Rev. Lett. 112, 055001 (2014); Hurricane et al., Nature 506, 343 (2014); Hurricane et al., Phys. Plasmas 21, 056314 (2014)] on the National Ignition Facility laser, we have nearly doubled the neutron yield and the hotspot pressure as compared to the implosions reported upon last year. The implosion velocity has been increased using a combination of the laser (higher power and energy), the hohlraum (depleted uranium wall material with higher opacity and lower specific heat than gold hohlraums), and the capsule (thinner capsules with less mass). We find that the neutron yield from these experiments scales systematically with a velocity-like parameter of the square root of the laser energy divided by the ablator mass. By connecting this parameter with the inferred implosion velocity (v), we find that for shots with primary yield >1 10{sup 15} neutrons, the total yield ??v{sup 9.4}. This increase is considerably faster than the expected dependence for implosions without alpha heating (?v{sup 5.9}) and is additional evidence that these experiments have significant alpha heating.

  12. The high-foot implosion campaign on the National Ignition Facility

    SciTech Connect (OSTI)

    Hurricane, O. A. Callahan, D. A.; Casey, D. T.; Dewald, E. L.; Dittrich, T. R.; Dppner, T.; Barrios Garcia, M. A.; Hinkel, D. E.; Berzak Hopkins, L. F.; Kervin, P.; Pape, S. Le; Ma, T.; MacPhee, A. G.; Milovich, J. L.; Moody, J.; Pak, A. E.; Patel, P. K.; Park, H.-S.; Remington, B. A.; Robey, H. F.; and others

    2014-05-15

    The High-Foot platform manipulates the laser pulse-shape coming from the National Ignition Facility laser to create an indirect drive 3-shock implosion that is significantly more robust against instability growth involving the ablator and also modestly reduces implosion convergence ratio. This strategy gives up on theoretical high-gain in an inertial confinement fusion implosion in order to obtain better control of the implosion and bring experimental performance in-line with calculated performance, yet keeps the absolute capsule performance relatively high. In this paper, we will cover the various experimental and theoretical motivations for the high-foot drive as well as cover the experimental results that have come out of the high-foot experimental campaign. At the time of this writing, the high-foot implosion has demonstrated record total deuterium-tritium yields (9.310{sup 15}) with low levels of inferred mix, excellent agreement with implosion simulations, fuel energy gains exceeding unity, and evidence for the bootstrapping associated with alpha-particle self-heating.

  13. Higher velocity, high-foot implosions on the National Ignition Facility laser

    SciTech Connect (OSTI)

    Callahan, D. A.; Hurricane, O. A.; Hinkel, D. E.; Dppner, T.; Ma, T.; Park, H. -S.; Barrios Garcia, M. A.; Berzak Hopkins, L. F.; Casey, D. T.; Cerjan, C. J.; Dewald, E. L.; Dittrich, T. R.; Edwards, M. J.; Haan, S. W.; Hamza, A. V.; Kline, J. L.; Knauer, J. P.; Kritcher, A. L.; Landen, O. L.; LePape, S.; MacPhee, A. G.; Milovich, J. L.; Nikroo, A.; Pak, A. E.; Patel, P. K.; Rygg, J. R.; Ralph, J. E.; Salmonson, J. D.; Spears, B. K.; Springer, P. T.; Tommasini, R.; Benedetti, L. R.; Bionta, R. M.; Bond, E. J.; Bradley, D. K.; Caggiano, J. A.; Field, J. E.; Fittinghoff, D. N.; Frenje, J.; Gatu Johnson, M.; Grim, G. P.; Hatarik, R.; Merrill, F. E.; Nagel, S. R.; Izumi, N.; Khan, S. F.; Town, R. P. J.; Sayre, D. B.; Volegov, P.; Wilde, C. H.

    2015-05-15

    By increasing the velocity in high foot implosions [Dittrich et al., Phys. Rev. Lett. 112, 055002 (2014); Park et al., Phys. Rev. Lett. 112, 055001 (2014); Hurricane et al., Nature 506, 343 (2014); Hurricane et al., Phys. Plasmas 21, 056314 (2014)] on the National Ignition Facility laser, we have nearly doubled the neutron yield and the hotspot pressure as compared to the implosions reported upon last year. The implosion velocity has been increased using a combination of the laser (higher power and energy), the hohlraum (depleted uranium wall material with higher opacity and lower specific heat than gold hohlraums), and the capsule (thinner capsules with less mass). We find that the neutron yield from these experiments scales systematically with a velocity-like parameter of the square root of the laser energy divided by the ablator mass. By connecting this parameter with the inferred implosion velocity (v), we find that for shots with primary yield >1e15 neutrons, the total yield ~ v???. This increase is considerably faster than the expected dependence for implosions without alpha heating ( ~v???) and is additional evidence that these experiments have significant alpha heating.

  14. A method for achieving ignition of a low voltage gas discharge device

    DOE Patents [OSTI]

    Kovarik, Vincent J. (Bohemia, NY); Hershcovitch, Ady (Mt. Sinai, NY); Prelec, Krsto (Setauket, NY)

    1988-01-01

    An electronic device of the type wherein current flow is conducted by an ionized gas comprising a cathode of the type heated by ionic bombardment, an anode, means for maintaining a predetermined pressure in the region between the anode and the cathode and means for maintaining a field in the region. The field, which is preferably a combined magnetic and electric field, is oriented so that the mean distance traveled by electrons before reaching the anode is increased. Because of this increased distance traveled electrons moving to the anode will ionize a larger number of gas atoms, thus reducing the voltage necesary to initiate gas breakdown. In a preferred embodiment the anode is a main hollow cathode and the cathode is a smaller igniter hollow cathode located within and coaxial with the main hollow cathode. An axial magnetic field is provided in the region between the hollow cathodes in order to facilitate gas breakdown in that region and initiate plasma discharge from the main hollow cathode.

  15. Alpha storage regime in high temperature sub-ignited D-T tokamaks

    SciTech Connect (OSTI)

    Zweben, S.J.; Furth, H.P.; Mikkelsen, D.R.; Redi, M.H.; Strachan, J.D.

    1988-07-01

    Alpha particle parameters in sub-ignited D-T tokamaks like TFTR can be optimized in a high temperature ''alpha storage regime '' in which the alpha particle thermalization time /tau//sub ..cap alpha../ is long (approx.1.0 sec) and in which the alpha particle source rate S/sub ..cap alpha../ is enhanced due to a beam-target and beam-beam reactions (by a factor of approx.2-3). Near reactor-level alpha instability parameters ..beta../sub ..cap alpha../(0) approx. n/sub ..cap alpha../(0)/n/sub e/(O) approx. 1% are predicted by simulation codes when Q approx. 0.5-1, while present TFTR ''supershots'' already have ..beta../sub ..cap alpha../(O) approx. n/sub /alpha/(O)/n/sub e/(O) /approx/ 0.1-0.2%. Plasmas in this regime can be used to test theories of collective alpha instabilities for the first time, and can be used to provide a strong (but transient) alpha heating pulse. An experimental scenario to exploit this regime is described. 28 refs., 5 figs., 5 tabs.,

  16. The shock/shear platform for planar radiation-hydrodynamics experiments on the National Ignition Facility

    SciTech Connect (OSTI)

    Doss, F. W.; Kline, J. L.; Flippo, K. A.; Perry, T. S.; DeVolder, B. G.; Tregillis, I.; Loomis, E. N.; Merritt, E. C.; Murphy, T. J.; Welser-Sherrill, L.; Fincke, J. R.

    2015-04-17

    An indirectly-driven shock tube experiment fielded on the National Ignition Facility (NIF) was used to create a high-energy-density hydrodynamics platform at unprecedented scale. Scaling up a shear-induced mixing experiment previously fielded at OMEGA, the NIF shear platform drives 130 ?m/ns shocks into a CH foam-filled shock tube (~ 60 mg/cc) with interior dimensions of 1.5 mm diameter and 5 mm length. The pulse-shaping capabilities of the NIF are used to extend the drive for >10 ns, and the large interior tube volumes are used to isolate physics-altering edge effects from the region of interest. The scaling of the experiment to the NIF allows for considerable improvement in maximum driving time of hydrodynamics, in fidelity of physics under examination, and in diagnostic clarity. Details of the experimental platform and post-shot simulations used in the analysis of the platform-qualifying data are presented. Hydrodynamic scaling is used to compare shear data from OMEGA with that from NIF, suggesting a possible change in the dimensionality of the instability at late times from one platform to the other.

  17. Three-dimensional simulations of National Ignition Facility implosions: Insight into experimental observables

    SciTech Connect (OSTI)

    Spears, Brian K. Munro, David H.; Sepke, Scott; Caggiano, Joseph; Clark, Daniel; Hatarik, Robert; Kritcher, Andrea; Sayre, Daniel; Yeamans, Charles; Knauer, James; Hilsabeck, Terry; Kilkenny, Joe

    2015-05-15

    We simulate in 3D both the hydrodynamics and, simultaneously, the X-ray and neutron diagnostic signatures of National Ignition Facility (NIF) implosions. We apply asymmetric radiation drive to study the impact of low mode asymmetry on diagnostic observables. We examine X-ray and neutron images as well as neutron spectra for these perturbed implosions. The X-ray images show hot spot evolution on small length scales and short time scales, reflecting the incomplete stagnation seen in the simulation. The neutron images show surprising differences from the X-ray images. The neutron spectra provide additional measures of implosion asymmetry. Flow in the hot spot alters the neutron spectral peak, namely, the peak location and width. The changes in the width lead to a variation in the apparent temperature with viewing angle that signals underlying hot spot asymmetry. We compare our new expectations based on the simulated data with NIF data. We find that some recent cryogenic layered experiments show appreciable temperature anisotropy indicating residual flow in the hot spot. We also find some trends in the data that do not reflect our simulation and theoretical understanding.

  18. Advanced laser particle accelerator development at LANL: from fast ignition to radiation oncology

    SciTech Connect (OSTI)

    Flippo, Kirk A; Gaillard, Sandrine A; Offermann, D T; Cobble, J A; Schmitt, M J; Gautier, D C; Kwan, T J T; Montgomery, D S; Kluge, Thomas; Bussmann, Micheal; Bartal, T; Beg, F N; Gall, B; Geissel, M; Korgan, G; Kovaleski, S; Lockard, T; Malekos, S; Schollmeier, M; Sentoku, Y; Cowan, T E

    2010-01-01

    Laser-plasma accelerated ion and electron beam sources are an emerging field with vast prospects, and promise many superior applications in a variety of fields such as hadron cancer therapy, compact radioisotope generation, table-top nuclear physics, laboratory astrophysics, nuclear forensics, waste transmutation, SN M detection, and inertial fusion energy. LANL is engaged in several projects seeking to develop compact high current and high energy ion and electron sources. We are especially interested in two specific applications: ion fast ignition/capsule perturbation and radiation oncology in conjunction with our partners at the ForschungsZentrum Dresden-Rossendorf (FZD). Laser-to-beam conversion efficiencies of over 10% are needed for practical applications, and we have already shown inherent etliciencies of >5% from flat foils, on Trident using only a 5th of the intensity and energy of the Nova Petawatt. With clever target designs, like structured curved cone targets, we have also been able to achieve major ion energy gains, leading to the highest energy laser-accelerated proton beams in the world. These new target designs promise to help usher in the next generation of particle sources realizing the potential of laser-accelerated beams.

  19. Mode 1 drive asymmetry in inertial confinement fusion implosions on the National Ignition Facility

    SciTech Connect (OSTI)

    Spears, Brian K. Edwards, M. J.; Hatchett, S.; Kritcher, A.; Lindl, J.; Munro, D.; Patel, P.; Robey, H. F.; Town, R. P. J.; Kilkenny, J.; Knauer, J.

    2014-04-15

    Mode 1 radiation drive asymmetry (pole-to-pole imbalance) at significant levels can have a large impact on inertial confinement fusion implosions at the National Ignition Facility (NIF). This asymmetry distorts the cold confining shell and drives a high-speed jet through the hot spot. The perturbed hot spot shows increased residual kinetic energy and reduced internal energy, and it achieves reduced pressure and neutron yield. The altered implosion physics manifests itself in observable diagnostic signatures, especially the neutron spectrum which can be used to measure the neutron-weighted flow velocity, apparent ion temperature, and neutron downscattering. Numerical simulations of implosions with mode 1 asymmetry show that the resultant simulated diagnostic signatures are moved toward the values observed in many NIF experiments. The diagnostic output can also be used to build a set of integrated implosion performance metrics. The metrics indicate that P{sub 1} has a significant impact on implosion performance and must be carefully controlled in NIF implosions.

  20. Backlighter development at the National Ignition Facility (NIF). Zinc to Zirconium

    DOE Public Access Gateway for Energy & Science Beta (PAGES Beta)

    Barrios, M. A.; Fournier, K. B.; Regan, S. P.; Landen, O.; May, M.; Opachich, Y. P.; Widmann, K.; Bradley, D. K.; Collins, G. W.

    2013-06-07

    A K-shell X-ray emission from laser-irradiated planar Zn, Ge, Br, and Zr foils was measured at the National Ignition Facility for laser irradiances in the range of 0.6–9.5 × 1015 W/cm 2. The incident laser power had a pre-pulse to enhance the laser-to-X-ray conversion efficiency (CE) of a 2–5 ns constant-intensity pulse used as the main laser drive. The measured CE into the 8–16 keV energy band ranged from 0.43% to 2%, while the measured CE into the He-like resonance 1s2–1s2p(1P) and intercombination 1s2–1s2p(3P) transitions, as well as from their 1s2(2s,2p)l–1s2p(2s,2p)l satellite transitions for l = 1, 2, 3, correspondingmore » to the Li-, Be-, and B-like resonances, respectively, ranged from 0.3% to 1.5%. Moreover, absolute and relative CE measurements are consistent with X-ray energy scaling of (hν) -3 to (hν) -5, where hν is the X-ray energy. The temporal evolution of the broadband X-ray power was similar to the main laser drive for ablation plasmas having a critical density surface.« less