National Library of Energy BETA

Sample records for hydrokinetic axial flow

  1. Effects of Large Energetic Vortices on Axial-Flow Hydrokinetic Turbines B. Gunawan1

    E-Print Network [OSTI]

    Siefert, Chris

    Effects of Large Energetic Vortices on Axial-Flow Hydrokinetic Turbines B. Gunawan1 , V.S. Neary1 C production in a model MHK turbine. Results show that the power generated by the turbine is significantly at the centerline of the energy extraction plane, or axial-flow turbine hub elevation, provide high resolution

  2. Evaluation of behaviour and survival of fish exposed to an axial-flow hydrokinetic turbine

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

    Amaral, Stephen; Bevelhimer, Mark S; Cada, Glenn F; Giza, Daniel; Jacobsen, Paul; McMahon, Brian; Pracheil, Brenda M

    2015-01-01

    Previous studies have evaluated fish injury and mortality at hydrokinetic (HK) turbines, but because these studies focused on the impacts of these turbines in situ they were unable to evaluate fish responses to controlled environmental characteristics (e.g., current velocity and light or dark conditions). In this study, we used juvenile hybrid Striped Bass (HSB; Striped Bass Morone saxatilis White Bass M. chrysops; N D 620), Rainbow Trout Oncorhynchus mykiss (N D 3,719), and White Sturgeon Acipenser transmontanus (N D 294) in a series of laboratory experiments to (1) evaluate the ability of fish to avoid entrainment through an axial-flow HKmore »turbine, (2) evaluate fish injury and survival associated with turbine entrainment, and (3) compare the effects of different HK turbines on fish. We found that the probability of turbine entrainment was species dependent and highest for HSB. Across species, current velocity influenced entrainment probability. Among entrained fish, observed survival rates were generally >0.95. The probability of injury for surviving entrained fish only differed from that for nonentrained fish for Rainbow Trout and in general was not >0.20. The probability of injury following entrainment was greater only for HSB, although there were no differences in injury rates between fish that were turbine entrained and those that were not, suggesting that injuries were not turbine related. Taking turbine entrainment, survival, and injury estimates together allowed us to estimate the probability of a randomly selected fish in a population proximate to an HK turbine surviving passage or remaining uninjured after passage. For species and current velocities for which there was a significant effect due to entrainment, we estimated, for instance, that HSB had a survival probability of 0.95 and that Rainbow Trout and White Sturgeon had a >0.99 probability of survival. Similarly, by combining these estimates with those from previous studies, we derived total passage survival probabilities >0.90 but generally approaching 1.00 across different HK turbine types, fish species, and fish lengths.« less

  3. Evaluation of behavior and survival of fish exposed to an axial-flow hydrokinetic turbine

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

    Amaral, Stephen V.; Bevelhimer, Mark S.; ?ada, Glenn F.; Giza, Daniel J.; Jacobson, Paul T.; McMahon, Brian J.; Pracheil, Brenda M.

    2015-02-06

    Previous studies have evaluated fish injury and mortality at hydrokinetic (HK) turbines, but because these studies focused on the impacts of these turbines in situ they were unable to evaluate fish responses to controlled environmental characteristics (e.g., current velocity and light or dark conditions). In this study, we used juvenile hybrid Striped Bass (HSB; Striped Bass Morone saxatilis White Bass M. chrysops; N D 620), Rainbow Trout Oncorhynchus mykiss (N D 3,719), and White Sturgeon Acipenser transmontanus (N D 294) in a series of laboratory experiments to (1) evaluate the ability of fish to avoid entrainment through an axial-flow HKmore »turbine, (2) evaluate fish injury and survival associated with turbine entrainment, and (3) compare the effects of different HK turbines on fish. We found that the probability of turbine entrainment was species dependent and highest for HSB. Across species, current velocity influenced entrainment probability. Among entrained fish, observed survival rates were generally >0.95. The probability of injury for surviving entrained fish only differed from that for nonentrained fish for Rainbow Trout and in general was not >0.20. The probability of injury following entrainment was greater only for HSB, although there were no differences in injury rates between fish that were turbine entrained and those that were not, suggesting that injuries were not turbine related. Taking turbine entrainment, survival, and injury estimates together allowed us to estimate the probability of a randomly selected fish in a population proximate to an HK turbine surviving passage or remaining uninjured after passage. For species and current velocities for which there was a significant effect due to entrainment, we estimated, for instance, that HSB had a survival probability of 0.95 and that Rainbow Trout and White Sturgeon had a >0.99 probability of survival. By combining these estimates with those from previous studies, we derived total passage survival probabilities >0.90 but generally approaching 1.00 across different HK turbine types, fish species, and fish lengths.« less

  4. Measurement of velocity deficit at the downstream of a 1:10 axial hydrokinetic turbine B. Gunawan1

    E-Print Network [OSTI]

    Siefert, Chris

    plane from upstream to downstream of the turbine at x/D = -10, -5, -3, -2, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10Measurement of velocity deficit at the downstream of a 1:10 axial hydrokinetic turbine model B, Minneapolis, MN 55414. ABSTRACT Wake recovery constrains the downstream spacing and density of turbines

  5. Piezoelectric axial flow microvalve

    DOE Patents [OSTI]

    Gemmen, Randall; Thornton, Jimmy; Vipperman, Jeffrey S.; Clark, William W.

    2007-01-09

    This invention is directed to a fuel cell operable with a quantity of fuel and a quantity of an oxidizer to produce electrical power, the fuel cell including a fuel cell body including a labyrinth system structured to permit the fuel and the oxidizer to flow therethrough; at least a first catalyst in fluid communication with the labyrinth; and at least a first microvalve operably disposed within at least a portion of the labyrinth. The microvalve utilizes a deflectable member operable upon the application of a voltage from a voltage source. The microvalve includes an elongated flow channel formed therein and extending substantially longitudinally between the first and second ends to permit substantially longitudinal flow of the fluid therethrough and between the first and second ends; and the deflectable member disposed on the valve body, the deflectable member including at least a first piezoelectric portion that is piezoelectrically operable to deflect the deflectable member between an open position and a closed position upon the application of a voltage, the deflectable member in the closed position being operable to resist the flow of the fluid through the flow channel.

  6. Flow Split Venturi, Axially-Rotated Valve

    DOE Patents [OSTI]

    Walrath, David E. (Laramie, WY); Lindberg, William R. (Laramie, WY); Burgess, Robert K. (Sheridan, WY); LaBelle, James (Murrieta, CA)

    2000-02-22

    The present invention provides an axially-rotated valve which permits increased flow rates and lower pressure drop (characterized by a lower loss coefficient) by using an axial eccentric split venturi with two portions where at least one portion is rotatable with respect to the other portion. The axially-rotated valve typically may be designed to avoid flow separation and/or cavitation at full flow under a variety of conditions. Similarly, the valve is designed, in some embodiments, to produce streamlined flow within the valve. An axially aligned outlet may also increase the flow efficiency. A typical cross section of the eccentric split venturi may be non-axisymmetric such as a semicircular cross section which may assist in both throttling capabilities and in maximum flow capacity using the design of the present invention. Such a design can include applications for freeze resistant axially-rotated valves and may be fully-opened and fully-closed in one-half of a complete rotation. An internal wide radius elbow typically connected to a rotatable portion of the eccentric venturi may assist in directing flow with lower friction losses. A valve actuator may actuate in an axial manner yet be uniquely located outside of the axial flow path to further reduce friction losses. A seal may be used between the two portions that may include a peripheral and diametrical seal in the same plane. A seal separator may increase the useful life of the seal between the fixed and rotatable portions.

  7. Free Flow Power Partners to Improve Hydrokinetic Turbine Performance...

    Energy Savers [EERE]

    as the device performed as expected, with no discernible harm to river-dwelling fish. Free Flow has also completed preliminary designs of utility-scale installations at a...

  8. Simulating Collisions for Hydrokinetic Turbines

    SciTech Connect (OSTI)

    Richmond, Marshall C.; Romero Gomez, Pedro DJ; Rakowski, Cynthia L.

    2013-10-01

    Evaluations of blade-strike on an axial-flow Marine Hydrokinetic turbine were conducted using a conventional methodology as well as an alternative modeling approach proposed in the present document. The proposed methodology integrates the following components into a Computa- tional Fluid Dynamics (CFD) model: (i) advanced eddy-resolving flow simulations, (ii) ambient turbulence based on field data, (iii) moving turbine blades in highly transient flows, and (iv) Lagrangian particles to mimic the potential fish pathways. The sensitivity of blade-strike prob- ability to the following conditions was also evaluated: (i) to the turbulent environment, (ii) to fish size and (iii) to mean stream flow velocity. The proposed methodology provided fraction of collisions and offered the capability of analyzing the causal relationships between the flow envi- ronment and resulting strikes on rotating blades. Overall, the conventional methodology largely overestimates the probability of strike, and lacks the ability to produce potential fish and aquatic biota trajectories as they interact with the rotating turbine. By using a set of experimental corre- lations of exposure-response of living fish colliding on moving blades, the occurrence, frequency and intensity of the particle collisions was next used to calculate the survival rate of fish crossing the MHK turbine. This step indicated survival rates always greater than 98%. Although the proposed CFD framework is computationally more expensive, it provides the advantage of evaluating multiple mechanisms of stress and injury of hydrokinetic turbine devices on fish.

  9. Interactions between turbulent open channel flow, power and the wake of an axial-flow marine turbine

    E-Print Network [OSTI]

    Siefert, Chris

    turbine Leonardo P. Chamorro1 , Craig Hill1 , Vincent Neary2 , Budi Gunawan2 , Roger Arndt1 , Fotis-flow marine hydrokinetic turbines was lacking. Advancing this area of knowledge within the field of marine and hydrokinetic energy research, development, and deployment will lead to more efficient turbine operations

  10. Modeling shrouded stator cavity flows in axial-flow compressors

    SciTech Connect (OSTI)

    Wellborn, S.R.; Tolchinsky, I.; Okiishi, T.H.

    2000-01-01

    Experiments and computational analyses were completed to understand the nature of shrouded stator cavity flows. From this understanding, a one-dimensional model of the flow through shrouded stator cavities was developed. This model estimates the leakage mass flow, temperature rise, and angular momentum increase through the cavity, given geometry parameters and the flow conditions at the interface between the cavity and primary flow path. This cavity model consists of two components, one that estimates the flow characteristics through the labyrinth seals and the other that predicts the transfer of momentum due to windage. A description of the one-dimensional model is given. The incorporation and use of the one-dimensional model in a multistage compressor primary flow analysis tool is described. The combination of this model and the primary flow solver was used to reliably simulate the significant impact on performance of the increase of hub seal leakage in a twelve-stage axial-flow compressor. Observed higher temperatures of the hub region fluid, different stage matching, and lower overall efficiencies and core flow than expected could be correctly linked to increased hub seal clearance with this new technique. The importance of including these leakage flows in compressor simulations is shown.

  11. Scalable Low-head Axial-type Venturi-flow Energy Scavenger |...

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

    Scalable Low-head Axial-type Venturi-flow Energy Scavenger Scalable Low-head Axial-type Venturi-flow Energy Scavenger Scalable Low-head Axial-type Venturi-flow Energy Scavenger...

  12. Technological cost%3CU%2B2010%3Ereduction pathways for axial%3CU%2B2010%3Eflow turbines in the marine hydrokinetic environment.

    SciTech Connect (OSTI)

    Laird, Daniel L.; Johnson, Erick L.; Ochs, Margaret Ellen; Boren, Blake

    2013-05-01

    This report considers and prioritizes potential technical costreduction pathways for axialflow turbines designed for tidal, river, and ocean current resources. This report focuses on technical research and development costreduction pathways related to the device technology rather than environmental monitoring or permitting opportunities. Three sources of information were utilized to understand current cost drivers and develop a list of potential costreduction pathways: a literature review of technical work related to axialflow turbines, the U.S. Department of Energy Reference Model effort, and informal webinars and other targeted interactions with industry developers. Data from these various information sources were aggregated and prioritized with respect to potential impact on the lifetime levelized cost of energy. The four most promising costreduction pathways include structural design optimization; improved deployment, maintenance, and recovery; system simplicity and reliability; and array optimization.

  13. Design, build and test of an axial flow hydrokinetic turbine with fatigue analysis

    E-Print Network [OSTI]

    Ketcham, Jerod W

    2010-01-01

    OpenProp is an open source propeller and turbine design and analysis code that has been in development since 2007 by MIT graduate students under the supervision of Professor Richard Kimball. In order to test the performance ...

  14. Effects of Large Energetic Vortices on Axial-Flow Hydrokinetic Turbines

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

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Homesum_a_epg0_fpd_mmcf_m.xls" ,"Available from WebQuantityBonneville Power Administration would like submitKansas Nuclear Profile 2010MesoscopyStaff »VehicleEffective

  15. Marine & Hydrokinetic Technologies

    SciTech Connect (OSTI)

    2011-07-01

    This fact sheet describes the Wind and Water Power Program's current approach to supporting the development and deployment of marine and hydrokinetic technologies.

  16. Rheological properties of soft-glassy flows from hydro-kinetic simulations

    E-Print Network [OSTI]

    R. Benzi; M. Bernaschi; M. Sbragaglia; S. Succi

    2014-02-28

    Based on numerical simulations of a lattice kinetic model for soft-glassy materials, we characterize the global rheology of a dense emulsion-like system, under three representative load conditions: Couette flow, time-oscillating Strain and Kolmogorov flow. It is found that in all cases the rheology is described by a Herschel-Bulkley (HB) relation, $\\sigma = {\\sigma}_{Y} + A S^{\\beta}$, with the yield stress ${\\sigma}_{Y}$ largely independent of the loading scenario. A proper rescaling of the HB parameters permits to describe heterogeneous flows with space-dependent stresses, based on the notion of cooperativity, as recently proposed to characterize the degree of non-locality of stress relaxation phenomena in soft-glassy materials.

  17. Effect of circumferential groove casing treatment parameters on axial compressor flow range

    E-Print Network [OSTI]

    Hanley, Brian K. (Brian Kyle)

    2010-01-01

    The impact on compressor flow range of circumferential casing grooves of varying groove depth, groove axial location, and groove axial extent is assessed against that of a smooth casing wall using computational experiments. ...

  18. Environmental Effects of Hydrokinetic Turbines on Fish: Desktop and Laboratory Flume Studies

    SciTech Connect (OSTI)

    Jacobson, Paul T.; Amaral, Stephen V.; Castro-Santos, Theodore; Giza, Dan; Haro, Alexander J.; Hecker, George; McMahon, Brian; Perkins, Norman; Pioppi, Nick

    2012-12-31

    This collection of three reports describes desktop and laboratory flume studies that provide information to support assessment of the potential for injury and mortality of fish that encounter hydrokinetic turbines of various designs installed in tidal and river environments. Behavioral responses to turbine exposure also are investigated to support assessment of the potential for disruptions to upstream and downstream movements of fish. The studies: (1) conducted an assessment of potential injury mechanisms using available data from studies with conventional hydro turbines; (2) developed theoretical models for predicting blade strike probabilities and mortality rates; and (3) performed flume testing with three turbine designs and several fish species and size groups in two laboratory flumes to estimate survival rates and document fish behavior. The project yielded three reports which this document comprises. The three constituent documents are addressed individually below Fish Passage Through Turbines: Application of Conventional Hydropower Data to Hydrokinetic Technologies Fish passing through the blade sweep of a hydrokinetic turbine experience a much less harsh physical environment than do fish entrained through conventional hydro turbines. The design and operation of conventional turbines results in high flow velocities, abrupt changes in flow direction, relatively high runner rotational and blade speeds, rapid and significant changes in pressure, and the need for various structures throughout the turbine passageway that can be impacted by fish. These conditions generally do not occur or are not significant factors for hydrokinetic turbines. Furthermore, compared to conventional hydro turbines, hydrokinetic turbines typically produce relatively minor changes in shear, turbulence, and pressure levels from ambient conditions in the surrounding environment. Injuries and mortality from mechanical injuries will be less as well, mainly due to low rotational speeds and strike velocities, and an absence of structures that can lead to grinding or abrasion injuries. Additional information is needed to rigorously assess the nature and magnitude of effects on individuals and populations, and to refine criteria for design of more fish-friendly hydrokinetic turbines. Evaluation of Fish Injury and Mortality Associated with Hydrokinetic Turbines Flume studies exposed fish to two hydrokinetic turbine designs to determine injury and survival rates and to assess behavioral responses. Also, a theoretical model developed for predicting strike probability and mortality of fish passing through conventional hydro turbines was adapted for use with hydrokinetic turbines and applied to the two designs evaluated during flume studies. The flume tests were conducted with the Lucid spherical turbine (LST), a Darrieus-type (cross flow) turbine, and the Welka UPG, an axial flow propeller turbine. Survival rates for rainbow trout tested with the LST were greater than 98% for both size groups and approach velocities evaluated. Turbine passage survival rates for rainbow trout and largemouth bass tested with the Welka UPG were greater than 99% for both size groups and velocities evaluated. Injury rates of turbine-exposed fish were low with both turbines and generally comparable to control fish. Video observations of the LST demonstrated active avoidance of turbine passage by a large proportion fish despite being released about 25 cm upstream of the turbine blade sweep. Video observations from behavior trials indicated few if any fish pass through the turbines when released farther upstream. The theoretical predictions for the LST indicated that strike mortality would begin to occur at an ambient current velocity of about 1.7 m/s for fish with lengths greater than the thickness of the leading edge of the blades. As current velocities increase above 1.7 m/s, survival was predicted to decrease for fish passing through the LST, but generally remained high (greater than 90%) for fish less than 200 mm in length. Strike mortality was not predicted to occur duri

  19. Effects of axial turbine tip shroud cavity flow on performance and durability

    E-Print Network [OSTI]

    Palmer, Timothy R. (Timothy Richard)

    2015-01-01

    Flow through tip shroud cavity in a representative axial turbine vane-rotor stage environment is assessed for its role in loss generation and turbine durability. Steady and unsteady three-dimensional flow computations, ...

  20. Estimation of the Risks of Collision or Strike to Freshwater Aquatic Organisms Resulting from Operation of Instream Hydrokinetic Turbines

    SciTech Connect (OSTI)

    Schweizer, Peter E; Cada, Glenn F; Bevelhimer, Mark S

    2010-05-01

    Hydrokinetic energy technologies have been proposed as renewable, environmentally preferable alternatives to fossil fuels for generation of electricity. Hydrokinetic technologies harness the energy of water in motion, either from waves, tides or from river currents. For energy capture from free-flowing rivers, arrays of rotating devices are most commonly proposed. The placement of hydrokinetic devices in large rivers is expected to increase the underwater structural complexity of river landscapes. Moore and Gregory (1988) found that structural complexity increased local fish populations because fish and other aquatic biota are attracted to structural complexity that provides microhabitats with steep flow velocity gradients (Liao 2007). However, hydrokinetic devices have mechanical parts, blades, wings or bars that move through the water column, posing a potential strike or collision risk to fish and other aquatic biota. Furthermore, in a setting with arrays of hydrokinetic turbines the cumulative effects of multiple encounters may increase the risk of strike. Submerged structures associated with a hydrokinetic (HK) project present a collision risk to aquatic organisms and diving birds (Cada et al. 2007). Collision is physical contact between a device or its pressure field and an organism that may result in an injury to that organism (Wilson et al. 2007). Collisions can occur between animals and fixed submerged structures, mooring equipment, horizontal or vertical axis turbine rotors, and structures that, by their individual design or in combination, may form traps. This report defines strike as a special case of collision where a moving part, such as a rotor blade of a HK turbine intercepts the path of an organism of interest, resulting in physical contact with the organism. The severity of a strike incidence may range from minor physical contact with no adverse effects to the organism to severe strike resulting in injury or death of the organism. Harmful effects to animal populations could occur directly (e.g., from strike mortality of individuals) or indirectly (e.g., if the loss of prey species to strike reduces food for predators). Although actively swimming or passively drifting animals may collide with any of the physical structures associated with hydrokinetic devices, turbine rotors are the most likely sources for risk of strike or significant collision (DOE 2009). It is also possible that during a close encounter with a HK device no physical contact will be made between the device and the organism, either because the animal avoids the device by successfully changing its direction of movement, or by successfully evading any moving parts of the device. Oak Ridge National Laboratory (ORNL) has been funded by the US Department of Energy (DOE) Waterpower Program to evaluate strike potential and consequences for Marine and Hydrokinetic (MHK) technologies in rivers and estuaries of the United States. We will use both predictive models and laboratory/field experiments to evaluate the likelihood and consequences of strike at HK projects in rivers. Efforts undertaken at ORNL address three objectives: (1) Assess strike risk for marine and freshwater organisms; (2) Develop experimental procedures to assess the risk and consequences of strike; and (3) Conduct strike studies in experimental flumes and field installations of hydrokinetic devices. During the first year of the study ORNL collected information from the Federal Energy Regulatory Commission (FERC) MHK database about geographical distribution of proposed hydrokinetic projects (what rivers or other types of systems), HK turbine design (horizontal axis, vertical axis, other), description of proposed axial turbine (number of blades, size of blades, rotation rate, mitigation measures), and number of units per project. Where site specific information was available, we compared the location of proposed projects rotors within the channel (e.g., along cutting edge bank, middle of thalweg, near bottom or in midwater) to the general locations of fish in the river (shoreline,

  1. Secondary air interaction with main flow in axial turbines

    E-Print Network [OSTI]

    Zlatinov, Metodi B. (Metodi Blagoev)

    2011-01-01

    Secondary air, known as purge air, is injected through seals in the hub and shroud of axial turbines to prevent hot gas ingestion into the endwall cavities. An investigation into the interaction of purge ow with turbine ...

  2. Submersible Generator for Marine Hydrokinetics

    SciTech Connect (OSTI)

    Robert S. Cinq-Mars; Timothy Burke; Dr. James Irish; Brian Gustafson; Dr. James Kirtley; Dr. Aiman Alawa

    2011-09-01

    A submersible generator was designed as a distinct and critical subassembly of marine hydrokinetics systems, specifically tidal and stream energy conversion. The generator is designed to work with both vertical and horizontal axis turbines. The final product is a high-pole-count, radial-flux, permanent magnet, rim mounted generator, initially rated at twenty kilowatts in a two-meter-per-second flow, and designed to leverage established and simple manufacturing processes. The generator was designed to work with a 3 meter by 7 meter Gorlov Helical Turbine or a marine hydrokinetic version of the FloDesign wind turbine. The team consisted of experienced motor/generator design engineers with cooperation from major US component suppliers (magnetics, coil winding and electrical steel laminations). Support for this effort was provided by Lucid Energy Technologies and FloDesign, Inc. The following tasks were completed: � Identified the conditions and requirements for MHK generators. � Defined a methodology for sizing and rating MHK systems. � Selected an MHK generator topology and form factor. � Completed electromechanical design of submersible generator capable of coupling to multiple turbine styles. � Investigated MHK generator manufacturing requirements. � Reviewed cost implications and financial viability. � Completed final reporting and deliverables

  3. Effect of flow oscillations on axial energy transport in a porous material

    SciTech Connect (OSTI)

    Siegel, R. (NASA Lewis Research Center, Cleveland, OH (USA))

    1987-02-01

    It has been shown analytically and experimentally that flow oscillations of a fluid within a channel can enhance the axial transfer of energy. The transport arises from an axial gradient in fluid temperature resulting from having reservoirs at different temperatures at either end of the channel. The present analysis develops relations for axial energy diffusion in a porous medium with oscillating flow. In some devices, such as the Sterling engine, there are regenerators with oscillating flow. Axial transport in the regenerator provides an energy loss; hence it is desirable to determine what factors can limit this diffusion. A regenerator in the form of a porous medium is difficult to model since the flow is continually disrupted by the irregularities of the porous structure. The formulation here will employ an internal heat transfer coefficient that couples the fluid and solid temperatures. The final result shows how the diffusion depends on the magnitude of the heat transfer coefficient and the maximum fluid displacement.

  4. Performance characteristics of a low pressure cyclone for axial-flow fan exhausts 

    E-Print Network [OSTI]

    Simpson, Shay Lynn

    1996-01-01

    on axial-flow fan exhausts to significantly reduce particulate emissions. Average emission concentrations, cut-point diameters, PMIO emission concentrations, and fractional efficiencies from this cyclone operating at different cyclone inlet velocities...

  5. Enviro effects of hydrokinetic turbines on fish | Department...

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

    effects of hydrokinetic turbines on fish Enviro effects of hydrokinetic turbines on fish Enviro effects of hydrokinetic turbines on fish 47fish-hkturbineinteractionseprijacobs...

  6. Blood flow through axially symmetric sections of compliant vessels: new effective closed models

    E-Print Network [OSTI]

    Canic, Suncica

    Blood flow through axially symmetric sections of compliant vessels: new effective closed models S-Stokes) equations for blood flow in compliant vessels. Several "effec- tive" one-dimensional models have been used independent ring model) to model the vessel wall behavior. In this work we obtain an effective system

  7. Active control of tip clearance flow in axial compressors

    E-Print Network [OSTI]

    Bae, Jinwoo W

    2001-01-01

    Control of compressor tip clearance flows is explored in a linear cascade using three types of fluidic actuators; Normal Synthetic Jet (NSJ; unsteady jet normal to the mean flow with zero net mass flux), Directed Synthetic ...

  8. A viscous instability in axially symmetric laminar shear flows

    E-Print Network [OSTI]

    Shakura, Nikolai

    2015-01-01

    A viscous instability in shearing laminar axisymmetric hydrodynamic flows around a gravitating center is described. In the linearized hydrodynamic equations written in the Boussinesq approximation with microscopic molecular transport coefficients, the instability arises when the viscous dissipation is taken into account in the energy equation. Using the local WKB approximation, we derive a third-order algebraic dispersion equation with two modes representing the modified Rayleigh modes R+ and R-, and the third X-mode. We show that in thin accretion flows the viscosity destabilizes one of the Rayleigh modes in a wide range of wavenumbers, while the X-mode always remains stable. In Keplerian flows, the instability increment is found to be a few Keplerian rotational periods at wavelengths with $kr\\sim 10-50$. This instability may cause turbulence in astrophysical accretion discs even in the absence of magnetic field.

  9. Dynamic control of rotating stall in axial flow compressors using aeromechanical feedback

    SciTech Connect (OSTI)

    Gysling, D.L.; Greitzer, E.M.

    1995-07-01

    Dynamic control of rotating stall in an axial flow compressor has been implemented using aeromechanical feedback. The control strategy developed used an array of wall jets, upstream of a single-stage compressor, which were regulated by locally reacting reed valves. These reed valves responded to the small-amplitude flow-field pressure perturbations that precede rotating stall. The valve design was such that the combined system, compressor plus reed valve controller, was stable under operating conditions that had been unstable without feedback. A 10 percent decrease in the stalling flow coefficient was obtained using the control strategy, and the extension of stall flow range was achieved with no measurable change in the steady-state performance of the compression system. The experiments demonstrate the first use of aeromechanical feedback to extend the stable operating range of an axial flow compressor, and the first use of local feedback and dynamic compensation techniques to suppress rotating stall. The design of the experiment was based on a two-dimensional stall inception model, which incorporated the effect of the aeromechanical feedback. The physical mechanism for rotating stall in axial flow compressors was examined with focus on the role of dynamic feedback in stabilizing compression system instability. As predicted and experimentally demonstrated, the effectiveness of the aeromechanical control strategy depends on a set of nondimensional control parameters that determine the interaction of the control strategy and the rotating stall dynamics.

  10. Measurement of the three-dimensional tip region flow field in an axial compressor

    SciTech Connect (OSTI)

    Stauter, R.C. )

    1993-07-01

    A two-color, five-beam LDV system has been configured to make simultaneous three-component velocity measurements of the flow field in a two-stage axial compressor model. The system has been used to make time-resolved measurements both between compressor blade rows and within the rotating blade passages in an axial compressor. The data show the nature and behavior of the complex, three-dimensional flow phenomena present in the tip region of a compressor as the convect downstream. In particular, the nature of the tip leakage vortex is apparent, being manifested by high blockage as well as the expected vortical motion. The data indicate that the radial flows associated with the tip leakage vortex begin to decrease while within the rotor passage, and that they temporarily increase aft of the passage.

  11. Simulating Blade-Strike on Fish passing through Marine Hydrokinetic Turbines

    SciTech Connect (OSTI)

    Romero Gomez, Pedro DJ; Richmond, Marshall C.

    2014-06-16

    The study reported here evaluated the occurrence, frequency, and intensity of blade strike of fish on an axial-flow marine hydrokinetic turbine by using two modeling approaches: a conventional kinematic formulation and a proposed Lagrangian particle- based scheme. The kinematic model included simplifying assumptions of fish trajectories such as distribution and velocity. The proposed method overcame the need for such simplifications by integrating the following components into a computational fluid dynamics (CFD) model: (i) advanced eddy-resolving flow simulation, (ii) generation of ambient turbulence based on field data, (iii) moving turbine blades in highly transient flows, and (iv) Lagrangian particles to mimic the potential fish pathways. The test conditions to evaluate the blade-strike probability and fish survival rate were: (i) the turbulent environment, (ii) the fish size, and (iii) the approaching flow velocity. The proposed method offered the ability to produce potential fish trajectories and their interaction with the rotating turbine. Depending upon the scenario, the percentile of particles that registered a collision event ranged from 6% to 19% of the released sample size. Next, by using a set of experimental correlations of the exposure-response of living fish colliding with moving blades, the simulated collision data were used as input variables to estimate the survival rate of fish passing through the operating turbine. The resulting survival rates were greater than 96% in all scenarios, which is comparable to or better than known survival rates for conventional hydropower turbines. The figures of strike probability and mortality rate were amplified by the kinematic model. The proposed method offered the advantage of expanding the evaluation of other mechanisms of stress and injury on fish derived from hydrokinetic turbines and related devices.

  12. Marine and Hydrokinetic Technology (MHK) Instrumentation, Measurement...

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

    Technology (MHK) Instrumentation, Measurement, and Computer Modeling Workshop Marine and Hydrokinetic Technology (MHK) Instrumentation, Measurement, and Computer Modeling Workshop...

  13. Impact of unsteady flow processes on the performance of a high speed axial flow compressor

    E-Print Network [OSTI]

    Botros, Barbara Brenda

    2008-01-01

    This thesis examines the unsteady interactions between blade rows in a high Mach number, highly-loaded compressor stage. Two straight vane/rotor configurations with different axial spacing between vane and rotor are ...

  14. Rotor whirl forces induced by the tip clearance effect in axial flow compressors

    SciTech Connect (OSTI)

    Ehrich, F. )

    1993-10-01

    It is now widely recognized that destabilizing forces, tending to generate forward rotor whirl, are generated in axial flow turbines as a result of the nonuniform torque induced by the nonuniform tip-clearance in a deflected rotor--the so called Thomas/Alford force. It is also recognized that there will be a similar effect in axial flow compressors, but qualitative considerations cannot definitively establish the magnitude or even the direction of the induced whirling forces--that is, if they will tend to forward or backward whirl. Applying a parallel compressor model to simulate the operation of a compressor rotor deflected radially in its clearance, it is possible to derive a quantitative estimate of the proportionality factor [beta] which relates the Thomas/Alford force in axial flow compressors (i.e., the tangential force generated by a radial deflection of the rotor) to the torque level in the compressor. The analysis makes use of experimental data from the GE Aircraft Engines Low Speed Research Compressor facility comparing the performance of three different axial flow compressors, each with four stages (typical of a mid-block of an aircraft gas turbine compressor) at two different clearances. It is found that the value of [beta] is in the range of +0.27 to [minus]0.71 in the vicinity of the stages' nominal operating line and +0.08 to [minus]1.25 in the vicinity of the stages' operation at peak efficiency. The value of [beta] reaches a level of between [minus]1.16 and [minus]3.36 as the compressor is operated near its stalled condition.

  15. Tip clearance flows in axial compressors: stall inception and stability enhancement

    E-Print Network [OSTI]

    Weichert, Stephanie April

    2012-02-07

    and 91 figures. Part of this dissertation has been presented in the following publication: Weichert, S., Day, I. & Freeman, C. (2011) Self-Regulating Casing Treat- ment for Axial Compressor Stability Enhancement. Proceedings of ASME Turbo Expo 2011, June... -span if unspecified W Rotor Relative Flow Velocity, mid-span if unspecified xii Superscripts and Subscripts 0 Stagnation condition 1 Rotor inlet conditions 2 Rotor exit, stator inlet conditions 3 Stator exit conditions a1 Deverson compressor bellmouth inlet d2...

  16. Multnomah County Hydrokinetic Feasibility Study: Final Feasibility Study Report

    SciTech Connect (OSTI)

    Stephen Spain

    2012-03-15

    HDR has completed a study of the technical, regulatory, and economic feasibility of installing hydrokinetic turbines under the Morrison, Broadway, and Sellwood bridges. The primary objective of installing hydrokinetic turbines is a demonstration of in-stream hydrokinetic technologies for public education and outreach. Due to the low gradient of the Lower Willamette and the effects of the tide, velocities in the area in consideration are simply not high enough to economically support a commercial installation. While the velocities in the river may at times provide enough energy for a commercial turbine to reach capacity, the frequency and duration of high flow events which provide suitable velocities is not sufficient to support a commercial hydrokinetic installation. We have observed that over an 11 year period, daily average velocities in the Lower Willamette exceeded a nominal cut-in speed of 0.75 m/s only 20% of the time, leaving net zero power production for the remaining 80% of days. The Sellwood Bridge site was estimated to have the best hydrokinetic resource, with an estimated average annual production of about 9,000 kWh. The estimated production could range from 2,500 kWh to 15,000 kWh. Based on these energy estimates, the amount of revenue generated through either a power purchase agreement (PPA) or recovered through net metering is not sufficient to repay the project costs within the life of the turbine. The hydrokinetic resource at the Morrison and Broadway Bridges is slightly smaller than at the Sellwood Bridge. While the Broadway and Morrison Bridges have existing infrastructure that could be utilized, the project is not expected to generate enough revenue to repay the investment. Despite low velocities and energy production, the sites themselves are favorable for installation of a demonstration or experimental project. With high public interest in renewable energy, the possibility exists to develop a hydrokinetic test site which could provide developers and scientists a location to temporarily deploy and test hydrokinetic devices, and also function as an educational tool for the general public. Bridge piers provide an excellent pre-existing anchor point for hydrokinetic devices, and existing infrastructure at the Morrison and Broadway Bridges may reduce installation costs. Opportunity exists to partner with local universities with engineering and environmental interest in renewable energy. A partnership with Portland State University�¢����s engineering school could provide students with an opportunity to learn about hydrokinetics through senior design projects. Oregon State University and University of Washington, which are partnered through the Northwest National Marine Renewable Energy Center (NNMREC) to study and test hydrokinetic technology, are also relatively local to the site. In addition to providing an opportunity for both public and private entities to learn technically about in-stream kinetics, this approach will encourage grant funding for outreach, education, and product development, while also serving as a positive community relations opportunity for the County and its partners.

  17. Marine and Hydrokinetic Technology Database

    DOE Data Explorer [Office of Scientific and Technical Information (OSTI)]

    DOE’s Marine and Hydrokinetic Technology Database provides up-to-date information on marine and hydrokinetic renewable energy, both in the U.S. and around the world. The database includes wave, tidal, current, and ocean thermal energy, and contains information on the various energy conversion technologies, companies active in the field, and development of projects in the water. Depending on the needs of the user, the database can present a snapshot of projects in a given region, assess the progress of a certain technology type, or provide a comprehensive view of the entire marine and hydrokinetic energy industry. Results are displayed as a list of technologies, companies, or projects. Data can be filtered by a number of criteria, including country/region, technology type, generation capacity, and technology or project stage. The database was updated in 2009 to include ocean thermal energy technologies, companies, and projects.

  18. New Report States That Hydrokinetic Turbines Have Minimal Environmenta...

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

    New Report States That Hydrokinetic Turbines Have Minimal Environmental Impacts on Fish New Report States That Hydrokinetic Turbines Have Minimal Environmental Impacts on Fish...

  19. Environmental Effects of Hydrokinetic Turbines on Fish: Desktop...

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

    Environmental Effects of Hydrokinetic Turbines on Fish: Desktop and Laboratory Flume Studies Environmental Effects of Hydrokinetic Turbines on Fish: Desktop and Laboratory Flume...

  20. Proceedings of the Hydrokinetic and Wave Energy Technologies...

    Office of Environmental Management (EM)

    Proceedings of the Hydrokinetic and Wave Energy Technologies Technical and Environmental Issues Workshop Proceedings of the Hydrokinetic and Wave Energy Technologies Technical and...

  1. Assessment and Mapping of the Riverine Hydrokinetic Resource...

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

    Assessment and Mapping of the Riverine Hydrokinetic Resource in the Continental United States Marine and Hydrokinetic Energy Projects Water Power for a Clean Energy Future...

  2. Request for Information Regarding the Testing of Marine and Hydrokinet...

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

    Request for Information Regarding the Testing of Marine and Hydrokinetic Systems Request for Information Regarding the Testing of Marine and Hydrokinetic Systems January 14, 2015 -...

  3. Potential Impacts of Hydrokinetic and Wave Energy Conversion...

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

    Potential Impacts of Hydrokinetic and Wave Energy Conversion Technologies on Aquatic Environments Potential Impacts of Hydrokinetic and Wave Energy Conversion Technologies on...

  4. Sandia Energy - Marine Hydrokinetics Technology: Market Acceleration

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

    on aquatic organisms, with early emphasis on the effects of electromagnetic fields (EMF), acoustic noise from currenttidal, wave and riverine hydrokinetic generators, toxicity...

  5. Energy 101: Marine and Hydrokinetic Energy

    ScienceCinema (OSTI)

    None

    2014-06-26

    See how marine and hydrokinetic technologies harness the energy of the ocean's waves, tides, and currents and convert it into electricity to power our homes, buildings and cities.

  6. Marine and Hydrokinetic Technologies Fact Sheet

    Office of Energy Efficiency and Renewable Energy (EERE)

    This fact sheet describes the Wind and Water Power Program's current approach to supporting the development and deployment of marine and hydrokinetic technologies.

  7. Energy 101: Marine and Hydrokinetic Energy

    SciTech Connect (OSTI)

    2013-04-29

    See how marine and hydrokinetic technologies harness the energy of the ocean's waves, tides, and currents and convert it into electricity to power our homes, buildings and cities.

  8. Sandia Energy - Investigations on Marine Hydrokinetic Turbine...

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

    Marine Hydrokinetic Turbine Foil Structural Health Monitoring Presented at GMREC METS Home Renewable Energy Energy Water Power News News & Events Systems Analysis Investigations on...

  9. Performance Evaluation of Axial Flow AG-1 FC and Prototype FM (High Strength) HEPA Filters - 13123

    SciTech Connect (OSTI)

    Giffin, Paxton K.; Parsons, Michael S.; Wilson, John A.; Waggoner, Charles A. [Institute for Clean Energy Technology, Mississippi State University, 205 Research Blvd Starkville, MS 39759 (United States)] [Institute for Clean Energy Technology, Mississippi State University, 205 Research Blvd Starkville, MS 39759 (United States)

    2013-07-01

    High efficiency particulate air (HEPA) filters are routinely used in DOE nuclear containment activities. The Nuclear Air Cleaning Handbook (NACH) stipulates that air cleaning devices and equipment used in DOE nuclear applications must meet the American Society of Mechanical Engineers (ASME) Code on Nuclear Air and Gas Treatment (AG-1) standard. This testing activity evaluates two different axial flow HEPA filters, those from AG-1 Sections FC and FM. Section FM is under development and has not yet been added to AG-1 due to a lack of qualification data available for these filters. Section FC filters are axial flow units that utilize a fibrous glass filtering medium. The section FM filters utilize a similar fibrous glass medium, but also have scrim backing. The scrim-backed filters have demonstrated the ability to endure pressure impulses capable of completely destroying FC filters. The testing activities presented herein will examine the total lifetime loading for both FC and FM filters under ambient conditions and at elevated conditions of temperature and relative humidity. Results will include loading curves, penetration curves, and testing condition parameters. These testing activities have been developed through collaborations with representatives from the National Nuclear Security Administration (NNSA), DOE Office of Environmental Management (DOE-EM), New Mexico State University, and Mississippi State University. (authors)

  10. Analysis of instability inception in high-speed multistage axial-flow compressors

    SciTech Connect (OSTI)

    Hendricks, G.J.; Sabnis, J.S.; Feulner, M.R.

    1997-10-01

    A nonlinear, two-dimensional, compressible dynamic model has been developed to study rotating stall/surge inception and development in high-speed, multistage, axial flow compressors. The flow dynamics are represented by the unsteady Euler equations, solved in each interblade row gap and inlet and exit ducts as two-dimensional domains, and in each blade passage as a one-dimensional domain. The resulting equations are solved on a computational grid. The boundary conditions between domains are represented by ideal turning coupled with empirical loss and deviation correlations. Results are presented comparing model simulations to instability inception data of an eleven stage, high-pressure-ratio compressor operating at both part and full power, and the results analyzed in the context of a linear modal analysis.

  11. Flow and axial dispersion in a sinusoidal-walled tube: Effects of inertial and unsteady flows

    SciTech Connect (OSTI)

    Richmond, Marshall C.; Perkins, William A.; Scheibe, Timothy D.; Lambert, Adam; Wood, Brian D.

    2013-12-01

    Dispersion in porous media flows has been the subject of much experimental, theoretical and numerical study. Here we consider a wavy-walled tube (a three-dimensional tube with sinusoidally-varying diameter) as a simplified conceptualization of flow in porous media, where constrictions represent pore throats and expansions pore bodies. A theoretical model for effective (macroscopic) longitudinal dispersion in this system has been developed by volume averaging the microscale velocity field. Direct numerical simulation using computational fluid dynamics (CFD) methods was used to compute velocity fields by solving the Navier-Stokes equations, and also to numerically solve the volume averaging closure problem, for a range of Reynolds numbers (Re) spanning the low-Re to inertial flow regimes, including one simulation at Re = 449 for which unsteady flow was observed. Dispersion values were computed using both the volume averaging solution and a random walk particle tracking method, and results of the two methods were shown to be consistent. Our results are compared to experimental measurements of dispersion in porous media and to previous theoretical results for the low-Re, Stokes flow regime. In the steady inertial regime we observe an power-law increase in effective longitudinal dispersion (DL) with Re, consistent with previous results. This rapid rate of increase is caused by trapping of solute in expansions due to flow separation (eddies). For the unsteady case (Re = 449), the rate of increase of DL with Re was smaller than that observed at lower Re. Velocity fluctuations in this regime lead to increased rates of solute mass transfer between the core flow and separated flow regions, thus diminishing the amount of tailing caused by solute trapping in eddies and thereby reducing longitudinal dispersion.

  12. Bifurcation analysis of surge and rotating stall in axial flow compressors

    SciTech Connect (OSTI)

    Abed, E.H. ); Houpt, P.K. . Corporate Research and Development Center); Hosny, W.M. . Engine Operability Div.)

    1993-10-01

    The surge and rotating stall post-instability behaviors of axial flow compressors are investigated from a bifurcation-theoretic perspective, using a model and system data presented by Greitzer (1976a). For this model, a sequence of local and global bifurcations of the nonlinear system dynamics is uncovered. This includes a global bifurcation of a pair of large-amplitude periodic solutions. Resulting from this bifurcation are a stable oscillation (surge) and an unstable oscillation (antisurge). The latter oscillation is found to have a deciding significance regarding the particular post-instability behavior experienced by the compressor. These results are used to reconstruct Greitzer's (1976b) findings regarding the manner in which post-instability behavior depends on system parameters. Although the model does not directly reflect non axisymmetric dynamics, use of a steady-state compressor characteristic approximating the measured characteristic of Greitzer (1976a) is found to result in conclusions that compare well with observation. Thus, the paper gives a convenient and simple explanation of the boundary between surge and rotating stall behaviors, without the use of more intricate models and analyses including non axisymmetric flow dynamics.

  13. Marine and Hydrokinetic Renewable Energy Devices, Potential Navigational Hazards and Mitigation Measures

    SciTech Connect (OSTI)

    Cool, Richard, M.; Hudon, Thomas, J.; Basco, David, R.; Rondorf, Neil, E.

    2009-12-01

    On April 15, 2008, the Department of Energy (DOE) issued a Funding Opportunity Announcement for Advanced Water Power Projects which included a Topic Area for Marine and Hydrokinetic Renewable Energy Market Acceleration Projects. Within this Topic Area, DOE identified potential navigational impacts of marine and hydrokinetic renewable energy technologies and measures to prevent adverse impacts on navigation as a sub-topic area. DOE defines marine and hydrokinetic technologies as those capable of utilizing one or more of the following resource categories for energy generation: ocean waves; tides or ocean currents; free flowing water in rivers or streams; and energy generation from the differentials in ocean temperature. PCCI was awarded Cooperative Agreement DE-FC36-08GO18177 from the DOE to identify the potential navigational impacts and mitigation measures for marine hydrokinetic technologies. A technical report addressing our findings is available on this Science and Technology Information site under the Product Title, "Marine and Hydrokinetic Renewable Energy Technologies: Potential Navigational Impacts and Mitigation Measures". This product is a brochure, primarily for project developers, that summarizes important issues in that more comprehensive report, identifies locations where that report can be downloaded, and identifies points of contact for more information.

  14. Rotating stall control of an axial flow compressor using pulsed air injection

    SciTech Connect (OSTI)

    D`Andrea, R.; Behnken, R.L.

    1997-10-01

    This paper presents the use of pulsed air injection to control rotating stall in a low-speed, axial flow compressor. In the first part of the paper, the injection of air is modeled as an unsteady shift of the compressor characteristic, and incorporated into a low dimensional model of the compressor. By observing the change in the bifurcation behavior of this model subject to nonlinear feedback, the viability of various air injection orientations is established. An orientation consistent with this analysis is then used for feedback control. By measuring the unsteady pressures near the rotor face, a control algorithm determines the magnitude and phase of the first mode of rotating stall and controls the injection of air in the front of the rotor face. Experimental results show that this technique eliminates the hysteresis loop normally associated with rotating stall. A parametric study is used to determine the optimal control parameters for suppression of stall. The resulting control strategy is also shown to suppress surge when a plenum is present. Using a high-fidelity model, the main features of the experimental results are duplicated via simulations.

  15. Marine and Hydrokinetic Energy Projects, Fiscal Years 2008-2014

    SciTech Connect (OSTI)

    2014-03-24

    This report covers the Wind and Water Power Technologies Office's Marine and Hydrokinetic Energy Projects from 2008 to 2014.

  16. Exit blade geometry and part-load performance of small axial flow propeller turbines: An experimental investigation

    SciTech Connect (OSTI)

    Singh, Punit; Nestmann, Franz

    2010-09-15

    A detailed experimental investigation of the effects of exit blade geometry on the part-load performance of low-head, axial flow propeller turbines is presented. Even as these turbines find important applications in small-scale energy generation using micro-hydro, the relationship between the layout of blade profile, geometry and turbine performance continues to be poorly characterized. The experimental results presented here help understand the relationship between exit tip angle, discharge through the turbine, shaft power, and efficiency. The modification was implemented on two different propeller runners and it was found that the power and efficiency gains from decreasing the exit tip angle could be explained by a theoretical model presented here based on classical theory of turbomachines. In particular, the focus is on the behaviour of internal parameters like the runner loss coefficient, relative flow angle at exit, mean axial flow velocity and net tangential flow velocity. The study concluded that the effects of exit tip modification were significant. The introspective discussion on the theoretical model's limitation and test facility suggests wider and continued experimentation pertaining to the internal parameters like inlet vortex profile and exit swirl profile. It also recommends thorough validation of the model and its improvement so that it can be made capable for accurate characterization of blade geometric effects. (author)

  17. US Department of Energy (DOE) National Lab Activities in Marine Hydrokinetics: Scaled Model

    E-Print Network [OSTI]

    Siefert, Chris

    US Department of Energy (DOE) National Lab Activities in Marine Hydrokinetics: Scaled Model Testing turbines specifically designed by the US Department of Energy for its Marine and Hydrokinetic Research. Keywords-- current energy conversion, performance testing, reference models, marine hydrokinetic

  18. Molecular tagging velocimetry measurements of axial flow in a concentrated vortex core

    E-Print Network [OSTI]

    Koochesfahani, Manoochehr M.

    , hydrocyclones) and natural (e.g., tornadoes, hurricanes, dust devils) flow fields. The interaction of vortices

  19. Marine and Hydrokinetic Renewable Energy Technologies: Potential Navigational Impacts and Mitigation Measures

    SciTech Connect (OSTI)

    Cool, Richard, M.; Hudon, Thomas, J.; Basco, David, R.; Rondorf, Neil, E.

    2009-12-10

    On April 15, 2008, the Department of Energy (DOE) issued a Funding Opportunity Announcement for Advanced Water Power Projects which included a Topic Area for Marine and Hydrokinetic Renewable Energy Market Acceleration Projects. Within this Topic Area, DOE identified potential navigational impacts of marine and hydrokinetic renewable energy technologies and measures to prevent adverse impacts on navigation as a sub-topic area. DOE defines marine and hydrokinetic technologies as those capable of utilizing one or more of the following resource categories for energy generation: ocean waves; tides or ocean currents; free flowing water in rivers or streams; and energy generation from the differentials in ocean temperature. PCCI was awarded Cooperative Agreement DE-FC36-08GO18177 from the DOE to identify the potential navigational impacts and mitigation measures for marine hydrokinetic technologies, as summarized herein. The contract also required cooperation with the U.S. Coast Guard (USCG) and two recipients of awards (Pacific Energy Ventures and reVision) in a sub-topic area to develop a protocol to identify streamlined, best-siting practices. Over the period of this contract, PCCI and our sub-consultants, David Basco, Ph.D., and Neil Rondorf of Science Applications International Corporation, met with USCG headquarters personnel, with U.S. Army Corps of Engineers headquarters and regional personnel, with U.S. Navy regional personnel and other ocean users in order to develop an understanding of existing practices for the identification of navigational impacts that might occur during construction, operation, maintenance, and decommissioning. At these same meetings, “standard” and potential mitigation measures were discussed so that guidance could be prepared for project developers. Concurrently, PCCI reviewed navigation guidance published by the USCG and international community. This report summarizes the results of this effort, provides guidance in the form of a checklist for assessing the navigational impacts of potential marine and hydrokinetic projects, and provides guidance for improving the existing navigational guidance promulgated by the USCG in Navigation Vessel Inspection Circular 02 07. At the request of the USCG, our checklist and mitigation guidance was written in a generic nature so that it could be equally applied to offshore wind projects. PCCI teleconferenced on a monthly basis with DOE, Pacific Energy Ventures and reVision in order to share information and review work products. Although the focus of our effort was on marine and hydrokinetic technologies, as defined above, this effort drew upon earlier work by the USCG on offshore wind renewable energy installations. The guidance provided herein can be applied equally to marine and hydrokinetic technologies and to offshore wind, which are collectively referred to by the USCG as Renewable Energy Installations.

  20. A numerical investigation of transonic axial compressor rotor flow using a low-Reynolds-number {kappa}-{epsilon} turbulence model

    SciTech Connect (OSTI)

    Arima, T.; Sonoda, T.; Shirotori, M.; Tamura, A.; Kikuchi, K.

    1999-01-01

    The authors have developed a computer simulation code for three-dimensional viscous flow in turbomachinery based on the time-averaged compressible Navier-Stokes equations and a low-Reynolds-number {kappa}-{epsilon} turbulence model. It is described in detail in this paper. The code is used to compute the flow fields for two types of rotor (a transonic fan NASA Rotor 67 and a transonic axial compressor NASA rotor 37), and numerical results are compared to experimental data based on aerodynamic probe and laser anemometer measurements. In the case of Rotor 67, calculated and experimental results are compared under the design speed to validate the code. The calculated results show good agreement with the experimental data, such as the rotor performance map and the spanwise distribution of total pressure, total temperature, and flow angle downstream of the rotor. In the case of Rotor 37, detailed comparisons between the numerical results and the experimental data are made under the design speed condition to assess the overall quality of the numerical solution. Furthermore, comparisons under the part-speed condition are used to investigate a flow field without passage shock. The results are well predicted qualitatively. However, considerable quantitative discrepancies remain in predicting the flow near the tip. In order to assess the predictive capabilities of the developed code, computed flow structures are presented with the experimental data for each rotor and the cause of the discrepancies is discussed.

  1. Evaporative capillary instability for flow in porous media under the influence of axial electric field

    SciTech Connect (OSTI)

    Kumar Awasthi, Mukesh, E-mail: mukeshiitr.kumar@gmail.com [Department of Mathematics, University of Petroleum and Energy Studies, Dehradun (India)

    2014-04-15

    We study the linear analysis of electrohydrodynamic capillary instability of the interface between two viscous, incompressible and electrically conducting fluids in a fully saturated porous medium, when the phases are enclosed between two horizontal cylindrical surfaces coaxial with the interface and, when there is mass and heat transfer across the interface. The fluids are subjected to a constant electric field in the axial direction. Here, we use an irrotational theory in which the motion and pressure are irrotational and the viscosity enters through the jump in the viscous normal stress in the normal stress balance at the interface. A quadratic dispersion relation that accounts for the growth of axisymmetric waves is obtained and stability criterion is given in terms of a critical value of wave number as well as electric field. It is observed that heat transfer has stabilizing effect on the stability of the considered system while medium porosity destabilizes the interface. The axial electric field has dual effect on the stability analysis.

  2. Assessment and Mapping of the Riverine Hydrokinetic Resource...

    Office of Environmental Management (EM)

    and results of the most rigorous assessment to date of the riverine hydrokinetic energy resource in the contiguous 48 states and Alaska, excluding tidal waters. Assessment...

  3. Assessment and Mapping of the Riverine Hydrokinetic Resource...

    Open Energy Info (EERE)

    riverine hydrokinetic energy resource in the contiguous 48 states and Alaska, excluding tidal waters. The assessment provides estimates of the gross, naturally available...

  4. Environmental Effects of Hydrokinetic Turbines on Fish: Desktop...

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

    provide information to support assessment of the potential for injury and mortality of fish that encounter hydrokinetic turbines of various designs installed in tidal and river...

  5. Environmental Effects of Hydrokinetic Turbines on Fish: Desktop...

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

    Environmental Effects of Hydrokinetic Turbines on Fish: Desktop and Laboratory Flume Studies 2012 Project Manager: Paul T. Jacobson 1 Principal Investigators: Stephen V. Amaral 2...

  6. First Commercial, Grid-Connected, Hydrokinetic Tidal Energy Project...

    Office of Science (SC) Website

    First Commercial, Grid-Connected, Hydrokinetic Tidal Energy Project in North America Small Business Innovation Research (SBIR) and Small Business Technology Transfer (STTR) SBIR...

  7. Sandia Energy - Biofouling Studies on Sandia's Marine Hydrokinetic...

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

    News News & Events Systems Analysis Materials Science Biofouling Studies on Sandia's Marine Hydrokinetic Coatings Initiated at PNNL's Sequim Bay Previous Next Biofouling Studies...

  8. Upcoming Funding Opportunity for Marine and Hydrokinetic Development...

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

    of Energy (DOE) announced a Notice of Intent to issue a funding opportunity titled "Marine and Hydrokinetic (MHK) Research and Development University Consortium." The goal of...

  9. Funding Opportunity Announcement for a Marine and Hydrokinetic...

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

    the U.S. Department of Energy (DOE) announced a 4 million funding opportunity titled "Marine and Hydrokinetic Development University Consortium." This funding opportunity is...

  10. Sandia Energy - Biofouling Studies on Sandia's Marine Hydrokinetic...

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

    Energy Water Power Partnership News News & Events Biofouling Studies on Sandia's Marine Hydrokinetic (MHK) Coatings Initiated at PNNL's Sequim Bay Previous Next Biofouling...

  11. Upcoming Funding Opportunity for Competitive Marine and Hydrokinetic...

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

    Competitive Marine and Hydrokinetic (MHK) Demonstrations at the Navy's Wave Energy Test Site (WETS)." The goal of this funding opportunity is to collect important performance and...

  12. Request for Information for Marine and Hydrokinetic Environmental...

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

    Water Power Program is seeking feedback from the marine and hydrokinetic (MHK) industry, academia, research laboratories, government agencies, and other stakeholders regarding the...

  13. Funding Opportunity Announcement for a Marine and Hydrokinetic...

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

    Announces 7.25 Million for Projects to Advance America's Emerging Marine & Hydrokinetic Industry Energy Department Announces 10 Million for Full-Scale Wave Energy Device Testing...

  14. Combustion in a Transonic Flow with Large Axial and Transverse Pressure Gradients

    E-Print Network [OSTI]

    Liu, Feng

    that we have named "turbine burners." References 1­7 present the progress to date on this emerging for bypass flows (turbofans), afterburners, and turbine burners. A simplified thermodynamic cy- cle portrayed for the turbine burner is given in Figure 2. Turbine burners are shown with continuous com- bustion through

  15. A study in three-dimensional chaotic dynamics: Granular flow and transport in a bi-axial spherical tumbler

    SciTech Connect (OSTI)

    Christov, Ivan C.; Lueptow, Richard M.; Ottino, Julio M.; Sturman, Rob

    2014-05-22

    We study three-dimensional (3D) chaotic dynamics through an analysis of transport in a granular flow in a half-full spherical tumbler rotated sequentially about two orthogonal axes (a bi-axial “blinking” tumbler). The flow is essentially quasi-two-dimensional in any vertical slice of the sphere during rotation about a single axis, and we provide an explicit exact solution to the model in this case. Hence, the cross-sectional flow can be represented by a twist map, allowing us to express the 3D flow as a linked twist map (LTM). We prove that if the rates of rotation about each axis are equal, then (in the absence of stochasticity) particle trajectories are restricted to two-dimensional (2D) surfaces consisting of a portion of a hemispherical shell closed by a “cap''; if the rotation rates are unequal, then particles can leave the surface they start on and traverse a volume of the tumbler. The period-one structures of the governing LTM are examined in detail: analytical expressions are provided for the location of period-one curves, their extent into the bulk of the granular material, and their dependence on the protocol parameters (rates and durations of rotations). Exploiting the restriction of trajectories to 2D surfaces in the case of equal rotation rates about the axes, a method is proposed for identifying and constructing 3D Kolmogorov--Arnold--Moser (KAM) tubes around the normally elliptic period-one curves. The invariant manifold structure arising from the normally hyperbolic period-one curves is also examined. When the motion is restricted to 2D surfaces, the structure of manifolds of the hyperbolic points in the bulk differs from that corresponding to hyperbolic points in the flowing layer. Each is reminiscent of a template provided by a non-integrable perturbation to a Hamiltonian system, though the governing LTM is not. This highlights the novel 3D chaotic behaviors observed in this model dynamical system.

  16. A study in three-dimensional chaotic dynamics: Granular flow and transport in a bi-axial spherical tumbler

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

    Christov, Ivan C.; Lueptow, Richard M.; Ottino, Julio M.; Sturman, Rob

    2014-05-22

    We study three-dimensional (3D) chaotic dynamics through an analysis of transport in a granular flow in a half-full spherical tumbler rotated sequentially about two orthogonal axes (a bi-axial “blinking” tumbler). The flow is essentially quasi-two-dimensional in any vertical slice of the sphere during rotation about a single axis, and we provide an explicit exact solution to the model in this case. Hence, the cross-sectional flow can be represented by a twist map, allowing us to express the 3D flow as a linked twist map (LTM). We prove that if the rates of rotation about each axis are equal, then (inmore »the absence of stochasticity) particle trajectories are restricted to two-dimensional (2D) surfaces consisting of a portion of a hemispherical shell closed by a “cap''; if the rotation rates are unequal, then particles can leave the surface they start on and traverse a volume of the tumbler. The period-one structures of the governing LTM are examined in detail: analytical expressions are provided for the location of period-one curves, their extent into the bulk of the granular material, and their dependence on the protocol parameters (rates and durations of rotations). Exploiting the restriction of trajectories to 2D surfaces in the case of equal rotation rates about the axes, a method is proposed for identifying and constructing 3D Kolmogorov--Arnold--Moser (KAM) tubes around the normally elliptic period-one curves. The invariant manifold structure arising from the normally hyperbolic period-one curves is also examined. When the motion is restricted to 2D surfaces, the structure of manifolds of the hyperbolic points in the bulk differs from that corresponding to hyperbolic points in the flowing layer. Each is reminiscent of a template provided by a non-integrable perturbation to a Hamiltonian system, though the governing LTM is not. This highlights the novel 3D chaotic behaviors observed in this model dynamical system.« less

  17. Stage effects on stalling and recovery of a high-speed 10-stage axial-flow compressor

    SciTech Connect (OSTI)

    Copenhaver, W.W.

    1988-01-01

    Results of a high-speed 10-stage axial-flow compressor test involving overall compressor and individual stage performance while stalling and operating in quasi-steady rotating stall are described. Test procedures and data-acquisition methods used to obtain the dynamic stalling and quasi-steady in-stall data are explained. Unstalled and in-stall time-averaged data obtained from the compressor operating at five different shaft speeds and one off-schedule variable vane condition are presented. Effects of compressor speed and variable geometry on overall compressor in-stall pressure rise and hysteresis extent are illustrated through the use of quasi-steady-stage temperature rise and pressure-rise characteristics. Results indicate that individual stage performance during overall compressor rotating stall operation varies considerably throughout the length of the compressor. The measured high-speed 10-stage test compressor individual stage pressure and temperature characteristics were input into a stage-by-stage dynamic compressor performance model. Comparison of the model results and measured pressures provided the additional validation necessary to demonstrate the model's ability to predict high-speed multistage compressor stalling and in-stall performance.

  18. Flow Flow Flow Flow Flow Flow Flow Flow Flow Flow

    E-Print Network [OSTI]

    Marchese, Francis

    Flow Flow Flow Flow Flow Flow Flow Flow Flow Flow Flow Flow Flow Flow Flow Flow Flow Flow Flow Flow Flow Flow Flow Flow Flow Flow Flow Flow Flow Flow Flow Flow Flow Flow Flow Flow Flow Flow Flow Flow Flow Flow Flow Flow Flow Flow Flow Flow Flow Flow Flow Flow Flow Flow Flow Flow Flow Flow Flow Flow

  19. EXPERIMENTAL AND NUMERICAL ANALYSIS OF THE FLOW INSIDE A CONFIGURATION INCLUDING AN AXIAL PUMP AND A TUBULAR

    E-Print Network [OSTI]

    Boyer, Edmond

    pressure signals upstream and downstream the pump and the exchanger. The pressure fluctuations. Keywords: Axial Pump, Pressure Fluctuations, Cavitation, Tubular Exchanger, Test Bench NOMENCLATURE Roman AND A TUBULAR EXCHANGER Mois´es Solis, Florent Ravelet,a) Sofiane Khelladi, and Farid Bakir Arts et Metiers

  20. Performance Evaluation of HYCOM-GOM for Hydrokinetic Resource Assessment in the Florida Strait

    SciTech Connect (OSTI)

    Neary, Vincent S; Gunawan, Budi; Ryou, Albert S

    2012-06-01

    The U.S. Department of Energy (DoE) is assessing and mapping the potential off-shore ocean current hydrokinetic energy resources along the U.S. coastline, excluding tidal currents, to facilitate market penetration of water power technologies. This resource assessment includes information on the temporal and three-dimensional spatial distribution of the daily averaged power density, and the overall theoretical hydrokinetic energy production, based on modeled historical simulations spanning a 7-year period of record using HYCOM-GOM, an ocean current observation assimilation model that generates a spatially distributed three-dimensional representation of daily averaged horizontal current magnitude and direction time series from which power density time series and their statistics can be derived. This study ascertains the deviation of HYCOM-GOM outputs, including transport (flow) and power density, from outputs based on three independent observation sources to evaluate HYCOM-GOM performance. The three independent data sources include NOAA s submarine cable data of transport, ADCP data at a high power density location, and HF radar data in the high power density region of the Florida Strait. Comparisons with these three independent observation sets indicate discrepancies with HYCOM model outputs, but overall indicate that the HYCOM-GOM model can provide an adequate assessment of the ocean current hydrokinetic resource in high power density regions like the Florida Strait. Additional independent observational data, in particular stationary ADCP measurements, would be useful for expanding this model performance evaluation study. ADCP measurements are rare in ocean environments not influenced by tides, and limited to one location in the Florida Strait. HF radar data, although providing great spatial coverage, is limited to surface currents only.

  1. Effect of boundary conditions on axial flow in a concentrated vortex core Richard K. Cohn and Manoochehr M. Koochesfahani

    E-Print Network [OSTI]

    Koochesfahani, Manoochehr M.

    of confined flows such as vortex chambers, and swirl separators (e.g., hydrocyclones). More recently

  2. Abrasion Testing of Critical Components of Hydrokinetic Devices

    SciTech Connect (OSTI)

    Worthington, Monty; Ali, Muhammad; Ravens, Tom

    2013-12-06

    The objective of the Abrasion Testing of Critical Components of Hydrokinetic Devices (Project) was to test critical components of hydrokinetic devices in waters with high levels of suspended sediment – information that is widely applicable to the hydrokinetic industry. Tidal and river sites in Alaska typically have high suspended sediment concentrations. High suspended sediment also occurs in major rivers and estuaries throughout the world and throughout high latitude locations where glacial inputs introduce silt into water bodies. In assessing the vulnerability of technology components to sediment induced abrasion, one of the greatest concerns is the impact that the sediment may have on device components such as bearings and seals, failures of which could lead to both efficiency loss and catastrophic system failures.

  3. Marine Hydrokinetic Energy Regulators Workshop: Lessons from Wind

    SciTech Connect (OSTI)

    Baring-Gould, E. Ian

    2015-09-03

    Ian Baring-Gould presented these lessons learned from wind energy to an audience of marine hydrokinetic regulators. Lessons learned spanned the areas of technology advances, using collaborative approaches to involve key stakeholders; using baseline studies to measure and prioritize wildlife impacts, and look at avoidance and mitigation options early in the process.

  4. Identifying How Marine and Hydrokinetic Devices Affect Aquatic Environments

    SciTech Connect (OSTI)

    Cada, G. F.; Copping, Andrea E.; Roberts, Jesse

    2011-04-24

    Significant research is under way to determine the potential environmental effects of marine and hydrokinetic energy systems. This research, being guided and funded by the U.S. Department of Energy, is intended to address knowledge gaps and facilitate installation and operation of these systems.

  5. Inertial waves and mean velocity profiles in a rotating pipe and a circular annulus with axial flow

    E-Print Network [OSTI]

    Yang, Yantao; Wu, J Z; Orlandi, Paolo

    2015-01-01

    In this paper we solve the inviscid inertial wave solutions in a circular pipe or annulus rotating constantly about its axis with moderate angular speed. The solutions are constructed by the so-called helical wave functions. We reveal that the mean velocity profiles must satisfy certain conditions to accommodate the inertial waves at the bulk region away from boundary. These conditions require the axial and azimuthal components of the mean velocity take the shapes of the zeroth and first order Bessel functions of the first kind, respectively. The theory is then verified by data obtained from direct numerical simulations for both rotating pipe and circular annulus, and excellent agreement is found between theory and numerical results. Large scale vortex clusters are found in the bulk region where the mean velocity profiles match the theoretical predictions. The success of the theory in rotating pipe, circular annulus, and streamwise rotating channel suggests that such inertial waves are quite common in wall bo...

  6. Hydro-kinetic approach to relativistic heavy ion collisions

    E-Print Network [OSTI]

    Akkelin, S V; Karpenko, Iu A; Sinyukov, Yu M

    2008-01-01

    We develop a combined hydro-kinetic approach which incorporates hydrodynamical expansion of the systems formed in \\textit{A}+\\textit{A} collisions and their dynamical decoupling described by escape probabilities. The method corresponds to a generalized relaxation time ($\\tau_{\\text{rel}}$) approximation for Boltzmann equation applied to inhomogeneous expanding systems; at small $\\tau_{\\text{rel}}$ it also allows one to catch the viscous effects in hadronic component - hadron-resonance gas. We demonstrate how the approximation of sudden freeze-out can be obtained within this dynamical picture of continuous emission and find that hypersurfaces, corresponding to sharp freeze-out limit, are momentum dependent. The pion $m_{T}$ spectra are computed in the developed hydro-kinetic model, and compared with those obtained from ideal hydrodynamics with the Cooper-Frye isothermal prescription. Our results indicate that there does not exist a universal freeze-out temperature for pions with different momenta, and support ...

  7. 2014 Water Power Program Peer Review: Marine and Hydrokinetic Technologies, Compiled Presentations (Presentation)

    SciTech Connect (OSTI)

    Not Available

    2014-02-01

    This document represents a collection of all presentations given during the EERE Wind and Water Power Program's 2014 Marine and Hydrokinetic Peer Review. The purpose of the meeting was to evaluate DOE-funded hydropower and marine and hydrokinetic R&D projects for their contribution to the mission and goals of the Water Power Program and to assess progress made against stated objectives.

  8. Free Flow Power Partners to Improve Hydrokinetic Turbine Performance and

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

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Home Page on Google Bookmark EERE: Alternative Fuels Data Center Home Page on Delicious Rank EERE: Alternative Fuelsof Energy Services » ProgramPolicySenateFlyer, Title VIFormatBlogFred L.Cost

  9. JEDI Marine and Hydrokinetic Model: User Reference Guide

    SciTech Connect (OSTI)

    Goldberg, M.; Previsic, M.

    2011-04-01

    The Jobs and Economic Development Impact Model (JEDI) for Marine and Hydrokinetics (MHK) is a user-friendly spreadsheet-based tool designed to demonstrate the economic impacts associated with developing and operating MHK power systems in the United States. The JEDI MHK User Reference Guide was developed to assist users in using and understanding the model. This guide provides information on the model's underlying methodology, as well as the sources and parameters used to develop the cost data utilized in the model. This guide also provides basic instruction on model add-in features, operation of the model, and a discussion of how the results should be interpreted.

  10. Marine and Hydrokinetic Technology Glossary | Open Energy Information

    Open Energy Info (EERE)

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Home Page on Google Bookmark EERE: Alternative Fuels Data Center Home Page on QA:QAsource History View NewTexas:Montezuma,Information MHKMHK5TransportManitouChangeMarcMarine and Hydrokinetic

  11. Split Venturi, Axially-Rotated Valve

    DOE Patents [OSTI]

    Walrath, David E. (Laramie, WY); Lindberg, William R. (Laramie, WY); Burgess, Robert K. (Sheridan, WY)

    2000-08-29

    The present invention provides an axially-rotated valve which permits increased flow rates and lower pressure drop (characterized by a lower loss coefficient) by using an axial eccentric split venturi with two portions where at least one portion is rotatable with respect to the other portion. The axially-rotated valve typically may be designed to avoid flow separation and/or cavitation at full flow under a variety of conditions. Similarly, the valve is designed, in some embodiments, to produce streamlined flow within the valve. A typical cross section of the eccentric split venturi may be non-axisymmetric such as a semicircular cross section which may assist in both throttling capabilities and in maximum flow capacity using the design of the present invention. Such a design can include applications for freeze resistant axially-rotated valves and may be fully-opened and fully-closed in one-half of a complete rotation. An internal wide radius elbow typically connected to a rotatable portion of the eccentric venturi may assist in directing flow with lower friction losses. A valve actuator may actuate in an axial manner yet be uniquely located outside of the axial flow path to further reduce friction losses. A seal may be used between the two portions that may include a peripheral and diametrical seal in the same plane.

  12. Hydro-kinetic approach to relativistic heavy ion collisions

    E-Print Network [OSTI]

    S. V. Akkelin; Y. Hama; Iu. A. Karpenko; Yu. M. Sinyukov

    2008-08-28

    We develop a combined hydro-kinetic approach which incorporates a hydrodynamical expansion of the systems formed in \\textit{A}+\\textit{A} collisions and their dynamical decoupling described by escape probabilities. The method corresponds to a generalized relaxation time ($\\tau_{\\text{rel}}$) approximation for the Boltzmann equation applied to inhomogeneous expanding systems; at small $\\tau_{\\text{rel}}$ it also allows one to catch the viscous effects in hadronic component - hadron-resonance gas. We demonstrate how the approximation of sudden freeze-out can be obtained within this dynamical picture of continuous emission and find that hypersurfaces, corresponding to a sharp freeze-out limit, are momentum dependent. The pion $m_{T}$ spectra are computed in the developed hydro-kinetic model, and compared with those obtained from ideal hydrodynamics with the Cooper-Frye isothermal prescription. Our results indicate that there does not exist a universal freeze-out temperature for pions with different momenta, and support an earlier decoupling of higher $p_{T}$ particles. By performing numerical simulations for various initial conditions and equations of state we identify several characteristic features of the bulk QCD matter evolution preferred in view of the current analysis of heavy ion collisions at RHIC energies.

  13. Live Webinar on the Funding Opportunity for Marine and Hydrokinetic Research and Development University Consortium

    Office of Energy Efficiency and Renewable Energy (EERE)

    On April 24, 2014 from 1:00 - 2:30 PM EDT, the Water Power Program will hold a live webinar to provide information to potential applicants for the Marine and Hydrokinetic (MHK) Research and...

  14. Advanced Turbulence Measurements and Signal Processing for Hydropower Flow Characterization

    E-Print Network [OSTI]

    and developed a data post-processing method to reduce the cost of flow and turbulence measurements at MHKAdvanced Turbulence Measurements and Signal Processing for Hydropower Flow Characterization and flow characterization within full scale conventional hydropower systems, at marine and hydrokinetic

  15. Marine and Hydrokinetic Energy Development Technical Support and General Environmental Studies Report on Outreach to Stakeholders for Fiscal Year 2009

    SciTech Connect (OSTI)

    Copping, Andrea E.; Geerlofs, Simon H.

    2010-01-22

    Report on activities working with stakeholders in the emerging marine and hydrokinetic energy industry during FY09, for DOE EERE Office of Waterpower.

  16. Field Measurements at River and Tidal Current Sites for Hydrokinetic Energy Development: Best Practices Manual

    SciTech Connect (OSTI)

    Neary, Vincent S; Gunawan, Budi

    2011-09-01

    In this report, existing data collection techniques and protocols for characterizing open channel flows are reviewed and refined to further address the needs of the MHK industry. The report provides an overview of the hydrodynamics of river and tidal channels, and the working principles of modern acoustic instrumentation, including best practices in remote sensing methods that can be applied to hydrokinetic energy site characterization. Emphasis is placed upon acoustic Doppler velocimeter (ADV) and acoustic-Doppler current profiler (ADCP) instruments, as these represent the most practical and economical tools for use in the MHK industry. Incorporating the best practices as found in the literature, including the parameters to be measured, the instruments to be deployed, the instrument deployment strategy, and data post-processing techniques. The data collected from this procedure aims to inform the hydro-mechanical design of MHK systems with respect to energy generation and structural loading, as well as provide reference hydrodynamics for environmental impact studies. The standard metrics and protocols defined herein can be utilized to guide field experiments with MHK systems.

  17. Sandia National Laboratories environmental fluid dynamics code. Marine Hydrokinetic Module User's Manual

    SciTech Connect (OSTI)

    James, Scott Carlton; Roberts, Jesse D.

    2014-03-01

    This document describes the marine hydrokinetic (MHK) input file and subroutines for the Sandia National Laboratories Environmental Fluid Dynamics Code (SNL-EFDC), which is a combined hydrodynamic, sediment transport, and water quality model based on the Environmental Fluid Dynamics Code (EFDC) developed by John Hamrick [1], formerly sponsored by the U.S. Environmental Protection Agency, and now maintained by Tetra Tech, Inc. SNL-EFDC has been previously enhanced with the incorporation of the SEDZLJ sediment dynamics model developed by Ziegler, Lick, and Jones [2-4]. SNL-EFDC has also been upgraded to more accurately simulate algae growth with specific application to optimizing biomass in an open-channel raceway for biofuels production [5]. A detailed description of the input file containing data describing the MHK device/array is provided, along with a description of the MHK FORTRAN routine. Both a theoretical description of the MHK dynamics as incorporated into SNL-EFDC and an explanation of the source code are provided. This user manual is meant to be used in conjunction with the original EFDC [6] and sediment dynamics SNL-EFDC manuals [7]. Through this document, the authors provide information for users who wish to model the effects of an MHK device (or array of devices) on a flow system with EFDC and who also seek a clear understanding of the source code, which is available from staff in the Water Power Technologies Department at Sandia National Laboratories, Albuquerque, New Mexico.

  18. THORs Power Method for Hydrokinetic Devices - Final Report

    SciTech Connect (OSTI)

    J. Turner Hunt; Joel Rumker

    2012-08-08

    Ocean current energy represents a vast untapped source of renewable energy that exists on the outer continental shelf areas of the 5 major continents. Ocean currents are unidirectional in nature and are perpetuated by thermal and salinity sea gradients, as well as coriolis forces imparted from the earth's rotation. This report details THORs Power Method, a breakthrough power control method that can provide dramatic increases to the capacity factor over and above existing marine hydrokinetic (MHK) devices employed in the extraction of energy from ocean currents. THORs Power Method represents a constant speed, variable depth operational method that continually locates the ocean current turbine at a depth at which the rated power of the generator is routinely achieved. Variable depth operation is achieved by using various vertical force effectors, including ballast tanks for variable weight, a hydrodynamic wing for variable lift or down force and drag flaps for variable vehicle drag forces.

  19. Laboratory Experiments on the Effects of Blade Strike from Hydrokinetic Energy Technologies on Larval and Juvenile Freshwater Fishes

    SciTech Connect (OSTI)

    Schweizer, Peter E; Cada, Glenn F; Bevelhimer, Mark S

    2012-03-01

    There is considerable interest in the development of marine and hydrokinetic energy projects in rivers, estuaries, and coastal ocean waters of the United States. Hydrokinetic (HK) technologies convert the energy of moving water in river or tidal currents into electricity, without the impacts of dams and impoundments associated with conventional hydropower or the extraction and combustion of fossil fuels. The Federal Energy Regulatory Commission (FERC) maintains a database that displays the geographical distribution of proposed HK projects in inland and tidal waters (FERC 2012). As of March 2012, 77 preliminary permits had been issued to private developers to study HK projects in inland waters, the development of which would total over 8,000 MW. Most of these projects are proposed for the lower Mississippi River. In addition, the issuance of another 27 preliminary permits for HK projects in inland waters, and 3 preliminary permits for HK tidal projects (totaling over 3,100 MW) were under consideration by FERC. Although numerous HK designs are under development (see DOE 2009 for a description of the technologies and their potential environmental effects), the most commonly proposed current-based projects entail arrays of rotating devices, much like submerged wind turbines, that are positioned in the high-velocity (high energy) river channels. The many diverse HK designs imply a diversity of environmental impacts, but a potential impact common to most is the risk for blade strike to aquatic organisms. In conventional hydropower generation, research on fish passage through reaction turbines at low-head dams suggested that strike and mortality for small fish could be low. As a consequence of the large surface area to mass ratio of small fish, the drag forces in the boundary layer flow at the surface of a rotor blade may pull small fish around the leading edge of a rotor blade without making physical contact (Turnpenny 1998, Turnpenny et al. 2000). Although there is concern that small, fragile fish early life stages may be unable to avoid being struck by the blades of hydrokinetic turbines, we found no empirical data in the published literature that document survival of earliest life-stage fish in passage by rotor blades. In addition to blade strike, research on passage of fish through conventional hydropower turbines suggested that fish mortalities from passage through the rotor swept area could also occur due to shear stresses and pressure chances in the water column (Cada et al. 1997, Turnpenny 1998). However, for most of the proposed HK turbine designs the rotors are projected to operate a lower RPM (revolutions per minute) than observed from conventional reaction turbines; the associated shear stress and pressure changes are expected to be lower and pose a smaller threat to fish survival (DOE 2009). Only a limited number of studies have been conducted to examine the risk of blade strike from hydrokinetic technologies to fish (Turnpenny et al. 1992, Normandeau et al. 2009, Seitz et al. 2011, EPRI 2011); the survival of drifting or weakly swimming fish (especially early life stages) that encounter rotor blades from hydrokinetic (HK) devices is currently unknown. Our study addressed this knowledge gap by testing how fish larvae and juveniles encountered different blade profiles of hydrokinetic devices and how such encounters influenced survivorship. We carried out a laboratory study designed to improve our understanding of how fish larvae and juvenile fish may be affected by encounters with rotor blades from HK turbines in the water column of river and ocean currents. (For convenience, these early life stages will be referred to as young of the year, YOY). The experiments developed information needed to quantify the risk (both probability and consequences) of rotor-blade strike to YOY fish. In particular, this study attempted to determine whether YOY drifting in a high-velocity flow directly in the path of the blade leading edge will make contact with the rotor blade or will bypass the blade while entrained in the boundary l

  20. Measuring axial pump thrust

    DOE Patents [OSTI]

    Suchoza, B.P.; Becse, I.

    1988-11-08

    An apparatus for measuring the hydraulic axial thrust of a pump under operation conditions is disclosed. The axial thrust is determined by forcing the rotating impeller off of an associated thrust bearing by use of an elongate rod extending coaxially with the pump shaft. The elongate rod contacts an impeller retainer bolt where a bearing is provided. Suitable measuring devices measure when the rod moves to force the impeller off of the associated thrust bearing and the axial force exerted on the rod at that time. The elongate rod is preferably provided in a housing with a heat dissipation mechanism whereby the hot fluid does not affect the measuring devices. 1 fig.

  1. Measuring axial pump thrust

    DOE Patents [OSTI]

    Suchoza, Bernard P. (McMurray, PA); Becse, Imre (Washington, PA)

    1988-01-01

    An apparatus for measuring the hydraulic axial thrust of a pump under operation conditions is disclosed. The axial thrust is determined by forcing the rotating impeller off of an associated thrust bearing by use of an elongate rod extending coaxially with the pump shaft. The elongate rod contacts an impeller retainer bolt where a bearing is provided. Suitable measuring devices measure when the rod moves to force the impeller off of the associated thrust bearing and the axial force exerted on the rod at that time. The elongate rod is preferably provided in a housing with a heat dissipation mechanism whereby the hot fluid does not affect the measuring devices.

  2. DISCRETE ELEMENT MODELING OF BLADE–STRIKE FREQUENCY AND SURVIVAL OF FISH PASSING THROUGH HYDROKINETIC TURBINES

    SciTech Connect (OSTI)

    Romero Gomez, Pedro DJ; Richmond, Marshall C.

    2014-04-17

    Evaluating the consequences from blade-strike of fish on marine hydrokinetic (MHK) turbine blades is essential for incorporating environmental objectives into the integral optimization of machine performance. For instance, experience with conventional hydroelectric turbines has shown that innovative shaping of the blade and other machine components can lead to improved designs that generate more power without increased impacts to fish and other aquatic life. In this work, we used unsteady computational fluid dynamics (CFD) simulations of turbine flow and discrete element modeling (DEM) of particle motion to estimate the frequency and severity of collisions between a horizontal axis MHK tidal energy device and drifting aquatic organisms or debris. Two metrics are determined with the method: the strike frequency and survival rate estimate. To illustrate the procedure step-by-step, an exemplary case of a simple runner model was run and compared against a probabilistic model widely used for strike frequency evaluation. The results for the exemplary case showed a strong correlation between the two approaches. In the application case of the MHK turbine flow, turbulent flow was modeled using detached eddy simulation (DES) in conjunction with a full moving rotor at full scale. The CFD simulated power and thrust were satisfactorily comparable to experimental results conducted in a water tunnel on a reduced scaled (1:8.7) version of the turbine design. A cloud of DEM particles was injected into the domain to simulate fish or debris that were entrained into the turbine flow. The strike frequency was the ratio of the count of colliding particles to the crossing sample size. The fish length and approaching velocity were test conditions in the simulations of the MHK turbine. Comparisons showed that DEM-based frequencies tend to be greater than previous results from Lagrangian particles and probabilistic models, mostly because the DEM scheme accounts for both the geometric aspects of the passage event ---which the probabilistic method does--- as well as the fluid-particle interactions ---which the Lagrangian particle method does. The DEM-based survival rates were comparable to laboratory results for small fish but not for mid-size fish because of the considerably different turbine diameters. The modeling framework can be used for applications that aim at evaluating the biological performance of MHK turbine units during the design phase and to provide information to regulatory agencies needed for the environmental permitting process.

  3. Wave and Hydrokinetics Interest Group 1st Meeting of 2009/2010 Year

    E-Print Network [OSTI]

    Wave and Hydrokinetics Interest Group 1st Meeting of 2009/2010 Year: With a Focus on wave Energy, Inc. All rights reserved. Marine Wave Energy Interest Group · Bill Toman, PG&E WaveConnect Project Manager is Chairman · Agenda 8:30-9:00 USA Project Status: PG&E WaveConnect, OPT Reedsport and Coos Bay

  4. OCEANS`13 MTS/IEEE SAN DIEGO, SEPTEMBER 2013 1 Electromechanical Emulation of Hydrokinetic

    E-Print Network [OSTI]

    Siefert, Chris

    interesting due to the high power density of river and tidal water currents as well as ocean waves that have Abstract--The pace of research and development efforts to integrate renewable power sources into modern paramount. In particular, hydrokinetic power is appealing due to its high energy density and superior

  5. Siting Study Framework and Survey Methodology for Marine and Hydrokinetic Energy Projects in Offshore Southeast Florida

    SciTech Connect (OSTI)

    Vinick, Charles

    2011-09-26

    Presentation from the 2011 Water Peer Review in which principal investigator discusses project progess to Investigate areas offshore southeast Florida that appeared most suitable for siting of marine and hydrokinetic energy conversion facilities that may be proposed in the Atlantic Ocean offshore of southeast Florida.

  6. Evaluating Effects of Stressors from Marine and Hydrokinetic Energy

    SciTech Connect (OSTI)

    Copping, Andrea E.; Blake, Kara M.; Hanna, Luke A.; Brandt, Charles A.; Ward, Jeffrey A.; Brandenberger, Jill M.; Gill, Gary A.; Carlson, Thomas J.; Elster, Jennifer L.; Jones, Mark E.; Watson, Bruce E.; Jepsen, Richard A.; Metzinger, Kurt

    2012-09-30

    Potential environmental effects of marine and hydrokinetic (MHK) energy development are not well understood, yet regulatory agencies are required to make decisions in spite of substantial uncertainty about environmental impacts and their long-term consequences. An understanding of risks associated with interactions between MHK installations and aquatic receptors, including animals, habitats, and ecosystems, can help define key uncertainties and focus regulatory actions and scientific studies on interactions of most concern. During FY 2012, Pacific Northwest National Laboratory (PNNL) continued to follow project developments on the two marine and hydrokinetic projects reviewed for Environmental Risk Evaluation System (ERES) screening analysis in FY 2011: a tidal project in the Gulf of Maine using Ocean Renewable Power Company TidGenTM turbines and a wave project planned for the coast of Oregon using Aquamarine Oyster surge devices. The ERES project in FY 2012 also examined two stressor–receptor interactions previously identified through the screening process as being of high importance: 1) the toxicity effects of antifouling coatings on MHK devices on aquatic resources and 2) the risk of a physical strike encounter between an adult killer whale and an OpenHydro turbine blade. The screening-level assessment of antifouling paints and coatings was conducted for two case studies: the Snohomish County Public Utility District No. 1 (SnoPUD) tidal turbine energy project in Admiralty Inlet, Puget Sound, Washington, and the Ocean Power Technologies (OPT) wave buoy project in Reedsport, Oregon. Results suggest minimal risk to aquatic biota from antifouling coatings used on MHK devices deployed in large estuaries or open ocean environments. For the strike assessment of a Southern Resident Killer Whale (SRKW) encountering an OpenHydro tidal turbine blade, PNNL teamed with colleagues from Sandia National Laboratories (SNL) to carry out an analysis of the mechanics and biological consequences of different blade strike scenarios. Results of these analyses found the following: 1) a SRKW is not likely to experience significant tissue injury from impact by an OpenHydro turbine blade; and 2) if whale skin behaves similarly to the materials considered as surrogates for the upper dermal layers of whale skin, it would not be torn by an OpenHydro blade strike. The PNNL/SNL analyses could not provide insight into the potential for more subtle changes to SRKWs from an encounter with a turbine, such as changes in behavior, or inform turbine interactions for other whales or other turbines. These analyses were limited by the available time frame in which results were needed and focused on the mechanical response of whale tissues and bone to blade strike. PNNL proposes that analyses of additional turbine designs and interactions with other marine mammals that differ in size, body conformation, and mass be performed.

  7. Assssment and Mapping of the Riverine Hydrokinetic Resource in the Continental United States

    SciTech Connect (OSTI)

    Jacobson, Paul T.; Ravens, Thomas M.; Cunningham, Keith W.; Scott, George

    2012-12-14

    The U.S. Department of Energy (DOE) funded the Electric Power Research Institute and its collaborative partners, University of Alaska ? Anchorage, University of Alaska ? Fairbanks, and the National Renewable Energy Laboratory, to provide an assessment of the riverine hydrokinetic resource in the continental United States. The assessment benefited from input obtained during two workshops attended by individuals with relevant expertise and from a National Research Council panel commissioned by DOE to provide guidance to this and other concurrent, DOE-funded assessments of water based renewable energy. These sources of expertise provided valuable advice regarding data sources and assessment methodology. The assessment of the hydrokinetic resource in the 48 contiguous states is derived from spatially-explicit data contained in NHDPlus ?a GIS-based database containing river segment-specific information on discharge characteristics and channel slope. 71,398 river segments with mean annual flow greater than 1,000 cubic feet per second (cfs) mean discharge were included in the assessment. Segments with discharge less than 1,000 cfs were dropped from the assessment, as were river segments with hydroelectric dams. The results for the theoretical and technical resource in the 48 contiguous states were found to be relatively insensitive to the cutoff chosen. Raising the cutoff to 1,500 cfs had no effect on estimate of the technically recoverable resource, and the theoretical resource was reduced by 5.3%. The segment-specific theoretical resource was estimated from these data using the standard hydrological engineering equation that relates theoretical hydraulic power (Pth, Watts) to discharge (Q, m3 s-1) and hydraulic head or change in elevation (??, m) over the length of the segment, where ? is the specific weight of water (9800 N m-3): ??? = ? ? ?? For Alaska, which is not encompassed by NPDPlus, hydraulic head and discharge data were manually obtained from Idaho National Laboratory?s Virtual Hydropower Prospector, Google Earth, and U.S. Geological Survey gages. Data were manually obtained for the eleven largest rivers with average flow rates greater than 10,000 cfs and the resulting estimate of the theoretical resource was expanded to include rivers with discharge between 1,000 cfs and 10,000 cfs based upon the contribution of rivers in the latter flow class to the total estimate in the contiguous 48 states. Segment-specific theoretical resource was aggregated by major hydrologic region in the contiguous, lower 48 states and totaled 1,146 TWh/yr. The aggregate estimate of the Alaska theoretical resource is 235 TWh/yr, yielding a total theoretical resource estimate of 1,381 TWh/yr for the continental US. The technically recoverable resource in the contiguous 48 states was estimated by applying a recovery factor to the segment-specific theoretical resource estimates. The recovery factor scales the theoretical resource for a given segment to take into account assumptions such as minimum required water velocity and depth during low flow conditions, maximum device packing density, device efficiency, and flow statistics (e.g., the 5 percentile flow relative to the average flow rate). The recovery factor also takes account of ?back effects? ? feedback effects of turbine presence on hydraulic head and velocity. The recovery factor was determined over a range of flow rates and slopes using the hydraulic model, HEC-RAS. In the hydraulic modeling, presence of turbines was accounted for by adjusting the Manning coefficient. This analysis, which included 32 scenarios, led to an empirical function relating recovery factor to slope and discharge. Sixty-nine percent of NHDPlus segments included in the theoretical resource estimate for the contiguous 48 states had an estimated recovery factor of zero. For Alaska, data on river slope was not readily available; hence, the recovery factor was estimated based on the flow rate alone. Segment-specific estimates of the theoretical resource were multiplied by the corresponding recovery factor to estimate

  8. Live Webinar on the Marine and Hydrokinetic Demonstrations at The Navy's Wave Energy Test Site Funding Opportunity Announcement

    Broader source: Energy.gov [DOE]

    On Wednesday, May 7, 2014 from 3:00 PM - 4:30 PM EDT the Water Power Program will hold an informational webinar on the Marine and Hydrokinetic (MHK) Demonstrations at The Navy's Wave Energy Test...

  9. US Synthetic Corp (TRL 4 Component)- The Development of Open, Water Lubricated Polycrystalline Diamond Thrust Bearings for use in Marine Hydrokinetic (MHK) Energy Machines

    Broader source: Energy.gov [DOE]

    US Synthetic Corp (TRL 4 Component) - The Development of Open, Water Lubricated Polycrystalline Diamond Thrust Bearings for use in Marine Hydrokinetic (MHK) Energy Machines

  10. Investigating the Influence of the Added Mass Effect to Marine Hydrokinetic Horizontal-Axis Turbines Using a General Dynamic Wake Wind Turbine Code

    SciTech Connect (OSTI)

    Maniaci, D. C.; Li, Y.

    2011-10-01

    This paper describes a recent study to investigate the applicability of a horizontal-axis wind turbine (HAWT) structural dynamics and unsteady aerodynamics analysis program (FAST and AeroDyn respectively) to modeling the forces on marine hydrokinetic (MHK) turbines. This paper summarizes the added mass model that has been added to AeroDyn. The added mass model only includes flow acceleration perpendicular to the rotor disc, and ignores added mass forces caused by blade deflection. A model of the National Renewable Energy Laboratory's (NREL) Unsteady Aerodynamics Experiment (UAE) Phase VI wind turbine was analyzed using FAST and AeroDyn with sea water conditions and the new added mass model. The results of this analysis exhibited a 3.6% change in thrust for a rapid pitch case and a slight change in amplitude and phase of thrust for a case with 30{sup o} of yaw.

  11. Investigating the Influence of the Added Mass Effect to Marine Hydrokinetic Horizontal-Axis Turbines Using a General Dynamic Wake Wind Turbine Code: Preprint

    SciTech Connect (OSTI)

    Maniaci, D. C.; Li, Y.

    2012-04-01

    This paper describes a recent study to investigate the applicability of a horizontal-axis wind turbine (HAWT) structural dynamics and unsteady aerodynamics analysis program (FAST and AeroDyn respectively) to modeling the forces on marine hydrokinetic (MHK) turbines. It summarizes the added mass model that has been added to AeroDyn. The added mass model only includes flow acceleration perpendicular to the rotor disc, and ignores added mass forces caused by blade deflection. A model of the National Renewable Energy Laboratory's (NREL) Unsteady Aerodynamics Experiment (UAE) Phase VI wind turbine was analyzed using FAST and AeroDyn with sea water conditions and the new added mass model. The results of this analysis exhibited a 3.6% change in thrust for a rapid pitch case and a slight change in amplitude and phase of thrust for a case with 30 degrees of yaw.

  12. Department of Energy Awards $37 Million for Marine and Hydrokinetic...

    Energy Savers [EERE]

    and free-flowing rivers represent a promising energy source located close to centers of electricity demand. The Department of Energy is working with industry, universities,...

  13. Report to Congress on the Potential Environmental Effects of Marine and Hydrokinetic Energy Technologies

    SciTech Connect (OSTI)

    Cada, Glenn

    2009-12-01

    This report focuses on potential impacts of marine and hydrokinetic technologies to aquatic environments (i.e. rivers, estuaries, and oceans), fish and fish habitats, ecological relationships, and other marine and freshwater aquatic resources. The report does not address impacts to terrestrial ecosystems and organisms that are common to other electricity-generating technologies (e.g., construction and maintenance of transmission lines) or possible effects on the human environment, including: human use conflicts, aesthetics, viewsheds, noise in the terrestrial environment, light, recreation, transportation, navigation, cultural resources, socioeconomic impacts.

  14. 2011 Marine Hydrokinetic Device Modeling Workshop: Final Report; March 1, 2011

    SciTech Connect (OSTI)

    Li, Y.; Reed, M.; Smith, B.

    2011-10-01

    This report summarizes the NREL Marine and Hydrokinetic Device Modeling Workshop. The objectives for the modeling workshop were to: (1) Review the designs of existing MHK device prototypes and discuss design and optimization procedures; (2) Assess the utility and limitations of modeling techniques and methods presently used for modeling MHK devices; (3) Assess the utility and limitations of modeling methods used in other areas, such as naval architecture and ocean engineering (e.g., oil & gas industry); and (4) Identify the necessary steps to link modeling with other important components that analyze MHK devices (e.g., tank testing, PTO design, mechanical design).

  15. Microsoft PowerPoint - MVD Hydrokinetics, SW Regional Hydropower Conference, 10 June 2010, rev 1.pptx

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

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Homesum_a_epg0_fpd_mmcf_m.xls" ,"Available from WebQuantityBonneville Power Administration wouldMass map shines light on darkMicroorganismsnow widely usingOverview ofWeSchoolHydrokinetic

  16. Chapter 4: Advancing Clean Electric Power Technologies | Marine and Hydrokinetic Power Technology Assessment

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

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Homesum_a_epg0_fpd_mmcf_m.xls" ,"Available from WebQuantity of Natural GasAdjustmentsShirleyEnergyTher i n c i p a lCaribElectricSouthApplying caulk to 13.1Carbon DioxideHydrokinetic

  17. Title: Sustainable Communities Based on a New Clean Energy Source -Marine & Hydrokinetic Power: Roosevelt Island and Beyond

    E-Print Network [OSTI]

    Walter, M.Todd

    Title: Sustainable Communities Based on a New Clean Energy Source - Marine & Hydrokinetic Power Earth Hour "a symbol of our commitment to sustainable energy for all," and underscored the need to "fuel in September launched an initiative to achieve universal and sustainable access to this vital resource, called

  18. Simulating Environmental Changes Due to Marine Hydrokinetic Energy Installations

    E-Print Network [OSTI]

    Siefert, Chris

    increasing attention upon renewable energy as a global solution to both energy and environmental challenges. Renewable energy sources such as wind power, solar power, or hydroelectric dams are increasingly implemented their potential environmental effects. When MHK devices extract energy from a system, volumetric flows and tidal

  19. International Standards Development for Marine and Hydrokinetic Renewable Energy - Final Report on Technical Status

    SciTech Connect (OSTI)

    Rondorf, Neil E.; Busch, Jason; Kimball, Richard

    2011-10-29

    This report summarizes the progress toward development of International Standards for Marine and Hydrokinetic Renewable Energy, as funded by the U.S. Department of Energy (DOE) under the International Electrotechnical Commission (IEC) Technical Committee 114. The project has three main objectives: 1. Provide funding to support participation of key U.S. industry technical experts in 6 (originally 4) international working groups and/or project teams (the primary standards-making committees) and to attend technical meetings to ensure greater U.S. involvement in the development of these standards. 2. Provide a report to DOE and industry stakeholders summarizing the IEC standards development process for marine and hydrokinetic renewable energy, new international standards and their justifications, and provide standards guidance to industry members. 3. Provide a semi-annual (web-based) newsletter to the marine renewable energy community. The newsletter will educate industry members and stakeholders about the processes, progress, and needs of the US efforts to support the international standards development effort. The newsletter is available at www.TC114.us

  20. Proceedings of the Hydrokinetic and Wave Energy Technologies Technical and Environmental Issues Workshop

    SciTech Connect (OSTI)

    2006-03-01

    Renewable energy technologies offer the promise of non-polluting alternatives to fossil and nuclear-fueled power plants to meet growing demand for electrical energy. Two emerging categories of renewable energy technologies, hydrokinetic and wave energy conversion devices, offer ways to tap the energy of moving water without impoundment (dams) or diversion required by many conventional hydroelectric facilities. These technologies include devices designed for deployment in natural streams, tidal estuaries, ocean currents, and constructed waterways, as well as devices designed to capture the energy of ocean waves. On October 26-28, 2005, 54 representatives from government, non-governmental organizations, and private business met to (1) identify the varieties of hydrokinetic energy and wave technology devices, their stages of development, and the projected cost to bring each to market; (2) identify where these technologies can best operate; (3) identify the potential environmental issues associated with these technologies and possible mitigation measures; (4) develop a list of research needs and/or practical solutions to address unresolved environmental issues. These workshop proceedings include detailed summaries of the 24 presentations made and the discussions that followed.

  1. Small core axial compressors for high efficiency jet aircraft

    E-Print Network [OSTI]

    DiOrio, Austin Graf

    2012-01-01

    This thesis quantifies mechanisms that limit efficiency in small core axial compressors, defined here as compressor exit corrected flow between 1.5 and 3.0 lbm/s. The first part of the thesis describes why a small engine ...

  2. Axially Tapered And Bilayer Microchannels For Evaporative Cooling Devices

    DOE Patents [OSTI]

    Nilson, Robert (Cardiff, CA); Griffiths, Stewart (Livermore, CA)

    2005-10-04

    The invention consists of an evaporative cooling device comprising one or more microchannels whose cross section is axially reduced to control the maximum capillary pressure differential between liquid and vapor phases. In one embodiment, the evaporation channels have a rectangular cross section that is reduced in width along a flow path. In another embodiment, channels of fixed width are patterned with an array of microfabricated post-like features such that the feature size and spacing are gradually reduced along the flow path. Other embodiments incorporate bilayer channels consisting of an upper cover plate having a pattern of slots or holes of axially decreasing size and a lower fluid flow layer having channel widths substantially greater than the characteristic microscale dimensions of the patterned cover plate. The small dimensions of the cover plate holes afford large capillary pressure differentials while the larger dimensions of the lower region reduce viscous flow resistance.

  3. Remote Monitoring of the Structural Health of Hydrokinetic Composite Turbine Blades

    SciTech Connect (OSTI)

    J.L. Rovey K. Chandrashekhara

    2012-09-21

    A health monitoring approach is investigated for hydrokinetic turbine blade applications. In-service monitoring is critical due to the difficult environment for blade inspection and the cost of inspection downtime. Composite blade designs have advantages that include long life in marine environments and great control over mechanical properties. Experimental strain characteristics are determined for static loads and free-vibration loads. These experiments are designed to simulate the dynamic characteristics of hydrokinetic turbine blades. Carbon/epoxy symmetric composite laminates are manufactured using an autoclave process. Four-layer composite beams, eight-layer composite beams, and two-dimensional eight-layer composite blades are instrumented for strain. Experimental results for strain measurements from electrical resistance gages are validated with theoretical characteristics obtained from in-house finite-element analysis for all sample cases. These preliminary tests on the composite samples show good correlation between experimental and finite-element strain results. A health monitoring system is proposed in which damage to a composite structure, e.g. delamination and fiber breakage, causes changes in the strain signature behavior. The system is based on embedded strain sensors and embedded motes in which strain information is demodulated for wireless transmission. In-service monitoring is critical due to the difficult environment for blade inspection and the cost of inspection downtime. Composite blade designs provide a medium for embedding sensors into the blades for in-situ health monitoring. The major challenge with in-situ health monitoring is transmission of sensor signals from the remote rotating reference frame of the blade to the system monitoring station. In the presented work, a novel system for relaying in-situ blade health measurements in hydrokinetic systems is described and demonstrated. An ultrasonic communication system is used to transmit sensor data underwater from the rotating frame of the blade to a fixed relay station. Data are then broadcast via radio waves to a remote monitoring station. Results indicate that the assembled system can transmit simulated sensor data with an accuracy of ±5% at a maximum sampling rate of 500 samples/sec. A power investigation of the transmitter within the blade shows that continuous max-sampling operation is only possible for short durations (~days), and is limited due to the capacity of the battery power source. However, intermittent sampling, with long periods between samples, allows for the system to last for very long durations (~years). Finally, because the data transmission system can operate at a high sampling rate for short durations or at a lower sampling rate/higher duty cycle for long durations, it is well-suited for short-term prototype and environmental testing, as well as long-term commercially-deployed hydrokinetic machines.

  4. Assessing the Effects of Marine and Hydrokinetic Energy Development on Marine and Estuarine Resources

    SciTech Connect (OSTI)

    Ward, Jeffrey A.; Schultz, Irvin R.; Woodruff, Dana L.; Roesijadi, Guritno; Copping, Andrea E.

    2010-07-30

    The world’s oceans and estuaries offer an enormous potential to meet the nation’s growing demand for energy. The use of marine and hydrokinetic (MHK) devices to harness the power of wave and tidal energy could contribute significantly toward meeting federal- and state-mandated renewable energy goals while supplying a substantial amount of clean energy to coastal communities. Locations along the eastern and western coasts of the United States between 40° and 70° north latitude are ideal for MHK deployment, and recent estimates of energy potential for the coasts of Washington, Oregon, and California suggest that up to 25 gigawatts could be generated from wave and tidal devices in these areas. Because energy derived from wave and tidal devices is highly predictable, their inclusion in our energy portfolio could help balance available sources of energy production, including hydroelectric, coal, nuclear, wind, solar, geothermal, and others.

  5. Cyclone reactor with internal separation and axial recirculation

    DOE Patents [OSTI]

    Becker, Frederick E. (Reading, MA); Smolensky, Leo A. (Concord, MA)

    1989-01-01

    A cyclone combustor apparatus contains a circular partition plate containing a central circular aperture. The partition plate divides the apparatus into a cylindrical precombustor chamber and a combustor chamber. A coal-water slurry is passed axially into the inlet end of the precombustor chamber, and primary air is passed tangentially into said chamber to establish a cyclonic air flow. Combustion products pass through the partition plate aperture and into the combustor chamber. Secondary air may also be passed tangentially into the combustor chamber adjacent the partition plate to maintain the cyclonic flow. Flue gas is passed axially out of the combustor chamber at the outlet end and ash is withdrawn tangentially from the combuston chamber at the outlet end. A first mixture of flue gas and ash may be tangentially withdrawn from the combustor chamber at the outlet end and recirculated to the axial inlet of the precombustor chamber with the coal-water slurry. A second mixture of flue gas and ash may be tangentially withdrawn from the outlet end of the combustor chamber and passed to a heat exchanger for cooling. Cooled second mixture is then recirculated to the axial inlet of the precombustor chamber. In another embodiment a single cyclone combustor chamber is provided with both the recirculation streams of the first mixture and the second mixture.

  6. Cyclone reactor with internal separation and axial recirculation

    DOE Patents [OSTI]

    Becker, F.E.; Smolensky, L.A.

    1988-07-19

    A cyclone combustor apparatus contains a circular partition plate containing a central circular aperture is described. The partition plate divides the apparatus into a cylindrical precombustor chamber and a combustor chamber. A coal-water slurry is passed axially into the inlet end of the precombustor chamber, and primary air is passed tangentially into said chamber to establish a cyclonic air flow. Combustion products pass through the partition plate aperture and into the combustor chamber. Secondary air may also be passed tangentially into the combustor chamber adjacent the partition plate to maintain the cyclonic flow. Flue gas is passed axially out of the combustor chamber at the outlet end and ash is withdrawn tangentially from the combustor chamber at the outlet end. A first mixture of flue gas and ash may be tangentially withdrawn from the combustor chamber at the outlet end and recirculated to the axial inlet of the precombustor chamber with the coal-water slurry. A second mixture may be tangentially withdrawn from the outlet end and passed to a heat exchanger for cooling. Cooled second mixture is then recirculated to the axial inlet of the precombustor chamber. In another embodiment a single cyclone combustor chamber is provided with both the recirculation streams of the first mixture and the second mixture. 10 figs.

  7. Siting Study Framework and Survey Methodology for Marine and Hydrokinetic Energy Project in Offshore Southeast Florida

    SciTech Connect (OSTI)

    Vinick, Charles; Riccobono, Antonino, MS; Messing, Charles G., Ph.D.; Walker, Brian K., Ph.D.; Reed, John K., Ph.D.

    2012-02-28

    Dehlsen Associates, LLC was awarded a grant by the United States Department of Energy (DOE) Golden Field Office for a project titled 'Siting Study Framework and Survey Methodology for Marine and Hydrokinetic Energy Project in Offshore Southeast Florida,' corresponding to DOE Grant Award Number DE-EE0002655 resulting from DOE funding Opportunity Announcement Number DE-FOA-0000069 for Topic Area 2, and it is referred to herein as 'the project.' The purpose of the project was to enhance the certainty of the survey requirements and regulatory review processes for the purpose of reducing the time, efforts, and costs associated with initial siting efforts of marine and hydrokinetic energy conversion facilities that may be proposed in the Atlantic Ocean offshore Southeast Florida. To secure early input from agencies, protocols were developed for collecting baseline geophysical information and benthic habitat data that can be used by project developers and regulators to make decisions early in the process of determining project location (i.e., the siting process) that avoid or minimize adverse impacts to sensitive marine benthic habitat. It is presumed that such an approach will help facilitate the licensing process for hydrokinetic and other ocean renewable energy projects within the study area and will assist in clarifying the baseline environmental data requirements described in the U.S. Department of the Interior Bureau of Ocean Energy Management, Regulation and Enforcement (formerly Minerals Management Service) final regulations on offshore renewable energy (30 Code of Federal Regulations 285, published April 29, 2009). Because projects generally seek to avoid or minimize impacts to sensitive marine habitats, it was not the intent of this project to investigate areas that did not appear suitable for the siting of ocean renewable energy projects. Rather, a two-tiered approach was designed with the first step consisting of gaining overall insight about seabed conditions offshore southeastern Florida by conducting a geophysical survey of pre-selected areas with subsequent post-processing and expert data interpretation by geophysicists and experienced marine biologists knowledgeable about the general project area. The second step sought to validate the benthic habitat types interpreted from the geophysical data by conducting benthic video and photographic field surveys of selected habitat types. The goal of this step was to determine the degree of correlation between the habitat types interpreted from the geophysical data and what actually exists on the seafloor based on the benthic video survey logs. This step included spot-checking selected habitat types rather than comprehensive evaluation of the entire area covered by the geophysical survey. It is important to note that non-invasive survey methods were used as part of this study and no devices of any kind were either temporarily or permanently attached to the seabed as part of the work conducted under this project.

  8. Environmentally Benign and Permanent Modifications to Prevent Biofouling on Marine and Hydrokinetic Devices

    SciTech Connect (OSTI)

    Zheng Zhang

    2012-04-19

    Semprus Biosciences is developing environmentally benign and permanent modifications to prevent biofouling on Marine and Hydrokinetic (MHK) devices. Biofouling, including growth on external surfaces by bacteria, algae, barnacles, mussels, and other marine organisms, accumulate quickly on MHK devices, causing mechanical wear and changes in performance. Biofouling on crucial components of hydrokinetic devices, such as rotors, generators, and turbines, imposes substantial mass and hydrodynamic loading with associated efficiency loss and maintenance costs. Most antifouling coatings leach toxic ingredients, such as copper and tributyltin, through an eroding process, but increasingly stringent regulation of biocides has led to interest in the development of non-biocidal technologies to control fouling. Semprus Biosciences research team is developing modifications to prevent fouling from a broad spectrum of organisms on devices of all shapes, sizes, and materials for the life of the product. The research team designed and developed betaine-based polymers as novel underwater coatings to resist the attachment of marine organisms. Different betaine-based monomers and polymers were synthesized and incorporated within various coating formulations. The formulations and application methods were developed on aluminum panels with required adhesion strength and mechanical properties. The coating polymers were chemically stable under UV, hydrolytic and oxidative environments. The sulfobetaine formulations are applicable as nonleaching and stable underwater coatings. For the first time, coating formulations modified with highly packed sulfobetaine polymers were prepared and demonstrated resistance to a broad spectrum of marine organisms. Assays for comparing nonfouling performance were developed to evaluate protein adsorption and bacteria attachment. Barnacle settlement and removal were evaluated and a 60-day field test was performed. Silicone substrates including a commercial fouling release coating were used for comparison. Compared with the unmodified silicone substrates, the sulfobetaine-modified formulations were able to exhibit a 98% reduction in fibrinogen adsorption, 97.0% (E. coli), 99.6% (S. aureus), and 99.5% (C. lytica) reduction in bacteria attachment, and 100% reduction in barnacles cyprid attachment. In addition to the significant improvement in fouling resistance of various organisms, the 60-day field test also showed an evident efficacy from visual assessment, foul rating, and fouling removal test. The research confirmed that the novel antifouling mechanism of betaine polymers provides a new avenue for marine coating development. The developed coatings out-performed currently used nontoxic underwater coatings in a broad spectrum of fouling resistance. By further developing formulations and processing methods for specific devices, the technology is ready for the next stage of development with demonstration in MHK systems.

  9. Marine and Hydrokinetic Technology (MHK) Instrumentation, Measurement, and Computer Modeling Workshop

    SciTech Connect (OSTI)

    Musial, W.; Lawson, M.; Rooney, S.

    2013-02-01

    The Marine and Hydrokinetic Technology (MHK) Instrumentation, Measurement, and Computer Modeling Workshop was hosted by the National Renewable Energy Laboratory (NREL) in Broomfield, Colorado, July 9-10, 2012. The workshop brought together over 60 experts in marine energy technologies to disseminate technical information to the marine energy community and collect information to help identify ways in which the development of a commercially viable marine energy industry can be accelerated. The workshop was comprised of plenary sessions that reviewed the state of the marine energy industry and technical sessions that covered specific topics of relevance. Each session consisted of presentations, followed by facilitated discussions. During the facilitated discussions, the session chairs posed several prepared questions to the presenters and audience to encourage communication and the exchange of ideas between technical experts. Following the workshop, attendees were asked to provide written feedback on their takeaways and their best ideas on how to accelerate the pace of marine energy technology development. The first four sections of this document give a general overview of the workshop format, provide presentation abstracts and discussion session notes, and list responses to the post-workshop questions. The final section presents key findings and conclusions from the workshop that suggest how the U.S. Department of Energy and national laboratory resources can be utilized to most effectively assist the marine energy industry.

  10. Identification and Prioritization of Analysis Cases for Marine and Hydrokinetic Energy Risk Screening

    SciTech Connect (OSTI)

    Anderson, Richard M.; Unwin, Stephen D.; Van Cleve, Frances B.

    2010-06-16

    In this report we describe the development of the Environmental Risk Evaluation System (ERES), a risk-informed analytical process for estimating the environmental risks associated with the construction and operation of marine and hydrokinetic energy generation projects. The development process consists of two main phases of analysis. In the first phase, preliminary risk analyses will take the form of screening studies in which key environmental impacts and the uncertainties that create risk are identified, leading to a better-focused characterization of the relevant environmental effects. Existence of critical data gaps will suggest areas in which specific modeling and/or data collection activities should take place. In the second phase, more detailed quantitative risk analyses will be conducted, with residual uncertainties providing the basis for recommending risk mitigation and monitoring activities. We also describe the process used for selecting three cases for fiscal year 2010 risk screening analysis using the ERES. A case is defined as a specific technology deployed in a particular location involving certain environmental receptors specific to that location. The three cases selected satisfy a number of desirable criteria: 1) they correspond to real projects whose deployment is likely to take place in the foreseeable future; 2) the technology developers are willing to share technology and project-related data; 3) the projects represent a diversity of technology-site-receptor characteristics; 4) the projects are of national interest, and 5) environmental effects data may be available for the projects.

  11. Quadrennial Technology Review 2015: Technology Assessments--Marine and Hydrokinetic Power

    SciTech Connect (OSTI)

    Sam Baldwin, Gilbert Bindewald, Austin Brown, Charles Chen, Kerry Cheung, Corrie Clark, Joe Cresko,

    2015-10-07

    Marine and hydrokinetic (MHK) technologies convert the energy of waves, tides, and river and ocean currents into electricity. With more than 50% of the U.S. population living within 50 miles of the nation’s coasts, MHK technologies hold significant potential to supply renewable electricity to consumers in coastal load centers, particularly in the near term in areas with high costs of electricity and longer term in high resource areas in close proximity to major coastal load centers. MHK resource assessments identify a total U.S. technical resource potential of approximately 1250–1850 terawatt-hours (TWh) of generation per year from ocean wave, ocean current, ocean tidal, and river current energy. Of this, the U.S. continental technical resource potential is approximately 500–750 TWh/year. For context, roughly 90,000 homes can be powered by 1 TWh of electricity generation each year. A cost-effective MHK industry could provide a substantial amount of electricity for the nation owing in large part to its unique advantages as a source of energy, including its vast resource potential, its close proximity to major coastal load centers, and its long-term predictability and near-term forecastability.

  12. Marine and Hydrokinetic Technology (MHK) Instrumentation, Measurement, and Computer Modeling Workshop

    SciTech Connect (OSTI)

    Musial, W.; Lawson, M.; Rooney, S.

    2013-02-01

    The Marine and Hydrokinetic Technology (MHK) Instrumentation, Measurement, and Computer Modeling Workshop was hosted by the National Renewable Energy Laboratory (NREL) in Broomfield, Colorado, July 9–10, 2012. The workshop brought together over 60 experts in marine energy technologies to disseminate technical information to the marine energy community, and to collect information to help identify ways in which the development of a commercially viable marine energy industry can be accelerated. The workshop was comprised of plenary sessions that reviewed the state of the marine energy industry and technical sessions that covered specific topics of relevance. Each session consisted of presentations, followed by facilitated discussions. During the facilitated discussions, the session chairs posed several prepared questions to the presenters and audience to encourage communication and the exchange of ideas between technical experts. Following the workshop, attendees were asked to provide written feedback on their takeaways from the workshop and their best ideas on how to accelerate the pace of marine energy technology development. The first four sections of this document give a general overview of the workshop format, provide presentation abstracts, supply discussion session notes, and list responses to the post-workshop questions. The final section presents key findings and conclusions from the workshop that suggest what the most pressing MHK technology needs are and how the U.S. Department of Energy (DOE) and national laboratory resources can be utilized to assist the marine energy industry in the most effective manner.

  13. The deep structure of Axial Volcano Michael West

    E-Print Network [OSTI]

    West, Michael

    available on Web #12;The deep structure of Axial Volcano IV. Magma Reservoir beneath Axial Volcano AxialThe deep structure of Axial Volcano Michael West Thesis defense, June 4, 2001 #12;Motivation What at Axial may be interpreted (NeMO, Neptune) #12;The deep structure of Axial Volcano IV. Magma Reservoir

  14. Psoriasis and psoriatic arthritis, axial type

    E-Print Network [OSTI]

    White, Katherine L.

    2001-01-01

    Psoriasis and psoriatic arthritis, axial type Katherine L.has a 20-year history of psoriasis, progressive psoriaticof psoriatic arthritis and psoriasis: a randomized trial.

  15. An Unbroken Axial Vector Current Conservation Law

    E-Print Network [OSTI]

    Rasulkhozha S. Sharafiddinov

    2015-05-28

    The mass, energy and momentum of the neutrino of a true flavor have an axial-vector nature. As a consequence, the left-handed truly neutral neutrino in an axial-vector field of emission can be converted into a right-handed one and vice versa. This predicts the unidenticality of masses, energies and momenta of neutrinos of the different components. Recognizing such a difference in masses, energies, momenta and accepting that the left-handed axial-vector neutrino and the right-handed antineutrino of true neutrality refer to long-lived C-odd leptons, and the right-handed truly neutral neutrino and the left-handed axial-vector antineutrino are of short-lived fermions of C-oddity, we would write a new CP-even Dirac equation taking into account the flavor symmetrical axial-vector mass, energy and momentum matrices. Their presence explains the spontaneous mirror symmetry violation, confirming that an axial-vector current conservation law has never violated. They reflect the availability of a mirror Minkowski space in which a neutrino is characterized by left as well as by right space-time coordinates. Therefore, it is not surprising that whatever the main purposes experiments about a quasielastic axial-vector mass say in favor of an axial-vector mirror Minkowski space-time.

  16. Axial interaction free-electron laser

    DOE Patents [OSTI]

    Carlsten, B.E.

    1997-09-02

    Electron orbits from a helical axial wiggler in an axial guide field are absolutely unstable as power is extracted from the particles. For off-axis beams an axial FEL mechanism exists when the axial electric field in a TM mode is wiggled to interact with the axial velocity of the electrons that form the beam. The interaction strength is comparable to that for helical FELs and is insensitive to beam orbit errors. The orbits for this mechanism are extremely stable in the absence of space charge and lead to high extraction efficiencies without particle phasing incoherence or interception. This interaction mechanism is suitable for use with intense annular electron beams for high power generation at microwave frequencies. 5 figs.

  17. Axial interaction free-electron laser

    DOE Patents [OSTI]

    Carlsten, Bruce E. (Los Alamos, NM)

    1997-01-01

    Electron orbits from a helical axial wiggler in an axial guide field are absolutely unstable as power is extracted from the particles. For off-axis beams an axial FEL mechanism exists when the axial electric field in a TM mode is wiggled to interact with the axial velocity of the electrons that form the beam. The interaction strength is comparable to that for helical FELs and is insensitive to beam orbit errors. The orbits for this mechanism are extremely stable in the absence of space charge and lead to high extraction efficiencies without particle phasing incoherence or interception. This interaction mechanism is suitable for use with intense annular electron beams for high power generation at microwave frequencies.

  18. Marine Hydrokinetic Turbine Power-Take-Off Design for Optimal Performance and Low Impact on Cost-of-Energy: Preprint

    SciTech Connect (OSTI)

    Beam, M.; Kline, B.; Elbing, B.; Straka, W.; Fontaine, A.; Lawson, M.; Li, Y.; Thresher, R.; Previsic, M.

    2012-04-01

    Marine hydrokinetic devices are becoming a popular method for generating marine renewable energy worldwide. These devices generate electricity by converting the kinetic energy of moving water, wave motion or currents, into electrical energy through the use of a Power-Take-Off (PTO) system. Most PTO systems incorporate a mechanical or hydraulic drive train, power generator and electric control/conditioning system to deliver the generated electric power to the grid at the required state. Like wind turbine applications, the PTO system must be designed for high reliability, good efficiency, and long service life with reasonable maintenance requirements, low cost and an appropriate mechanical design for anticipated applied steady and unsteady loads. The ultimate goal of a PTO design is high efficiency, low maintenance and cost with a low impact on the device Cost-of-Energy (CoE).

  19. Marine Hydrokinetic Turbine Power-Take-Off Design for Optimal Performance and Low Impact on Cost-of-Energy: Preprint

    SciTech Connect (OSTI)

    Beam, M.; Kline, B.; Elbing, B.; Straka, W.; Fontaine, A.; Lawson, M.; Li, Y.; Thresher, R.; Previsic, M.

    2013-02-01

    Marine hydrokinetic devices are becoming a popular method for generating marine renewable energy worldwide. These devices generate electricity by converting the kinetic energy of moving water, wave motion or currents, into electrical energy through the use of a power-take-off (PTO) system. Most PTO systems incorporate a mechanical or hydraulic drivetrain, power generator, and electric control/conditioning system to deliver the generated electric power to the grid at the required state. Like wind turbine applications, the PTO system must be designed for high reliability, good efficiency, and long service life with reasonable maintenance requirements, low cost, and an appropriate mechanical design for anticipated applied steady and unsteady loads. The ultimate goal of a PTO design is high efficiency and low maintenance and cost, with a low impact on the device cost-of-energy (CoE).

  20. Performance limits of axial turbomachine stages

    E-Print Network [OSTI]

    Hall, David Kenneth

    2011-01-01

    This thesis assesses the limits of stage efficiency for axial compressor and turbine stages. A stage model is developed, consisting of a specified geometry and a surface velocity distribution with turbulent boundary layers. ...

  1. Chiral corrections to hyperon axial form factors

    SciTech Connect (OSTI)

    Jiang Fujiun; Tiburzi, B. C.

    2008-05-01

    We study the complete set of flavor-changing hyperon axial-current matrix elements at small momentum transfer. Using partially quenched heavy baryon chiral perturbation theory, we derive the chiral and momentum behavior of the axial and induced pseudoscalar form factors. The meson pole contributions to the latter posses a striking signal for chiral physics. We argue that the study of hyperon axial matrix elements enables a systematic lattice investigation of the efficacy of three-flavor chiral expansions in the baryon sector. This can be achieved by considering chiral corrections to SU(3) symmetry predictions, and their partially quenched generalizations. In particular, despite the presence of eight unknown low-energy constants, we are able to make next-to-leading order symmetry breaking predictions for two linear combinations of axial charges.

  2. Isosinglet Versus Octet Scalar Axial Current

    E-Print Network [OSTI]

    Kirchbach, M

    1998-01-01

    The flavor SU(3)_f group symmetry of QCD is systematically considered as the heavy charmed quark limit of SU(4)_f. Within that scheme the introduction of an octet axial current suggests physical manifestations of the SU(4)_f flavor singlet axial current. As long as the latter is known to be nonobservable due to instanton effects, Gell-Mann's choice for the realization of the su(3)_f algebra does not apply to the particular case of neutral axial currents. Rather, Weyl's choice for the SU(4)_f generators has to be used which leads to a neutral strong axial current having same structure as the weak one. According to that, the light quark flavors participate the neutral axial vector current exclusively via the third component of its isotriplet part, while the strange quarks create a purely isosinglet component. An octet axial current part is absent. As a consequence, the contact gradient coupling of octet scalar pseudoscalar mesons to the nucleon will be an isosinglet rather than an octet scalar. It will, therefo...

  3. An Unbroken Axial Vector Current Conservation Law

    E-Print Network [OSTI]

    Sharafiddinov, Rasulkhozha S

    2015-01-01

    The mass, energy and momentum of the neutrino of a true flavor have an axial-vector nature. As a consequence, the left-handed truly neutral neutrino in an axial-vector field of emission can be converted into a right-handed one and vice versa. This predicts the unidenticality of masses, energies and momenta of neutrinos of the different components. Recognizing such a difference in masses, energies, momenta and accepting that the left-handed axial-vector neutrino and the right-handed antineutrino of true neutrality refer to long-lived C-odd leptons, and the right-handed truly neutral neutrino and the left-handed axial-vector antineutrino are of short-lived fermions of C-oddity, we would write a new CP-even Dirac equation taking into account the flavor symmetrical axial-vector mass, energy and momentum matrices. Their presence explains the spontaneous mirror symmetry violation, confirming that an axial-vector current conservation law has never violated. They reflect the availability of a mirror Minkowski space i...

  4. CALTECH ASCI TECHNICAL REPORT 130 Axial motion and scalar transport in stretched spiral vortices

    E-Print Network [OSTI]

    Barr, Al

    of Technology, Pasadena, California 91125 T. S. Lundgren Department of Aerospace Engineering and Mechanics-vortex flow. The dominant term in the velocity energy spectrum contributed by the axial velocity is found of the azimuthal velocity. This gives a k 7/3 spectrum at large wave numbers, compared to the k 5/3 component

  5. Scalar Resonances in Axially Symmetric Spacetimes

    E-Print Network [OSTI]

    Ignacio F. Ranea-Sandoval; Héctor Vucetich

    2015-03-12

    We study properties of resonant solutions to the scalar wave equation in several axially symmetric spacetimes. We prove that non-axial resonant modes do not exist neither in the Lanczos dust cylinder, the $(2+1)$ extreme BTZ spacetime nor in a class of simple rotating wormhole solutions. Moreover, we find unstable solutions to the wave equation in the Lanczos dust cylinder and in the $r^2 <0$ region of the extreme $(2+1)$ BTZ spacetime, two solutions that possess closed timelike curves. Similarities with previous results obtained for the Kerr spacetime are explored.

  6. Skyrme RPA for spherical and axially symmetric nuclei

    E-Print Network [OSTI]

    Anton Repko; Jan Kvasil; V. O. Nesterenko; P. -G. Reinhard

    2015-10-05

    Random Phase Approximation (RPA) is the basic method for calculation of excited states of nuclei over the Hartree-Fock ground state, suitable also for energy density functionals (EDF or DFT). We developed a convenient formalism for expressing densities and currents in a form of reduced matrix elements, which allows fast calculation of spectra for spherical nuclei. All terms of Skyrme functional were taken into account, so it is possible to calculate electric, magnetic and vortical/toroidal/compression transitions and strength functions of any multipolarity. Time-odd (spin) terms in Skyrme functional become important for magnetic M1 and isovector toroidal E1 transitions. It was also found that transition currents in pygmy region (low-lying part of E1 resonance) exhibit isoscalar toroidal flow, so the previously assumed picture of neutron-skin vibration is not the only mechanism present in pygmy transitions. RPA calculations with heavy axially-symmetric nuclei now become feasible on ordinary PC. Detailed formulae for axial Skyrme RPA are given. Some numerical results are shown in comparison with the approximate approach of separable RPA, previously developed in our group for fast calculation of strength functions.

  7. Co-axial, high energy gamma generator

    DOE Patents [OSTI]

    Reijonen, Jani Petteri (Princeton, NJ); Gicquel, Frederic (Pennington, NJ)

    2011-08-16

    A gamma ray generator includes an ion source in a first chamber. A second chamber is configured co-axially around the first chamber at a lower second pressure. Co-axially arranged plasma apertures separate the two chambers and provide for restricted passage of ions and gas from the first to the second chamber. The second chamber is formed by a puller electrode having at least one long channel aperture to draw ions from the first chamber when the puller electrode is subject to an appropriate applied potential. A plurality of electrodes rings in the third chamber in third pressure co-axially surround the puller electrode and have at least one channel corresponding to the at least one puller electrode aperture and plasma aperture. The electrode rings increase the energy of the ions to a selected energy in stages in passing between successive pairs of the electrodes by application of an accelerating voltage to the successive pairs of accelerator electrodes. A target disposed co-axially around the plurality of electrodes receives the beam of accelerated ions, producing gamma rays.

  8. Simulation of in-core neutron noise measurements for axial void profile reconstruction in boiling water reactors

    SciTech Connect (OSTI)

    Dykin, V.; Pazsit, I.

    2012-07-01

    A possibility to reconstruct the axial void profile from the simulated in-core neutron noise which is caused by density fluctuations in a Boiling Water Reactor (BWR) heated channel is considered. For this purpose, a self-contained model of the two-phase flow regime is constructed which has quantitatively and qualitatively similar properties to those observed in real BWRs. The model is subsequently used to simulate the signals of neutron detectors induced by the corresponding perturbations in the flow density. The bubbles are generated randomly in both space and time using Monte-Carlo techniques. The axial distribution of the bubble production is chosen such that the mean axial void fraction and void velocity follow the actual values of BWRs. The induced neutron noise signals are calculated and then processed by the standard signal analysis methods such as Auto-Power Spectral Density (APSD) and Cross-Power Spectral Density (CPSD). Two methods for axial void and velocity profiles reconstruction are discussed: the first one is based on the change of the break frequency of the neutron auto-power spectrum with axial core elevation, while the second refers to the estimation of transit times of propagating steam fluctuations between different axial detector positions. This paper summarizes the principles of the model and presents a numerical testing of the qualitative applicability to estimate the required parameters for the reconstruction of the void fraction profile from the neutron noise measurements. (authors)

  9. Skyrme RPA for spherical and axially symmetric nuclei

    E-Print Network [OSTI]

    Repko, Anton; Nesterenko, V O; Reinhard, P -G

    2015-01-01

    Random Phase Approximation (RPA) is the basic method for calculation of excited states of nuclei over the Hartree-Fock ground state, suitable also for energy density functionals (EDF or DFT). We developed a convenient formalism for expressing densities and currents in a form of reduced matrix elements, which allows fast calculation of spectra for spherical nuclei. All terms of Skyrme functional were taken into account, so it is possible to calculate electric, magnetic and vortical/toroidal/compression transitions and strength functions of any multipolarity. Time-odd (spin) terms in Skyrme functional become important for magnetic M1 and isovector toroidal E1 transitions. It was also found that transition currents in pygmy region (low-lying part of E1 resonance) exhibit isoscalar toroidal flow, so the previously assumed picture of neutron-skin vibration is not the only mechanism present in pygmy transitions. RPA calculations with heavy axially-symmetric nuclei now become feasible on ordinary PC. Detailed formul...

  10. Sandia Energy - EC Publications

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

    HEALTH MONITORING OF MARINE HYDROKINETIC STRUCTURES (91) Field Measurements at River and Tidal Current Sites for Hydrokinetic Energy Development: Best Practices Manual (40) Flow...

  11. Chiral corrections and the axial charge of the delta

    SciTech Connect (OSTI)

    Jiang Fujiun; Tiburzi, Brian C.

    2008-07-01

    Chiral corrections to the delta axial charge are determined using heavy baryon chiral perturbation theory. Knowledge of this axial coupling is necessary to assess virtual-delta contributions to nucleon and delta observables. We give isospin relations useful for a lattice determination of the axial coupling. Furthermore, we detail partially quenched chiral corrections, which are relevant to address partial quenching and/or mixed action errors in lattice calculations of the delta axial charge.

  12. Piping inspection carriage having axially displaceable sensor

    DOE Patents [OSTI]

    Zollinger, William T. (Martinez, GA); Treanor, Richard C. (Augusta, GA)

    1994-01-01

    A pipe inspection instrument carriage for use with a pipe crawler for performing internal inspections of piping surfaces. The carriage has a front leg assembly, a rear leg assembly and a central support connecting the two assemblies and for mounting an instrument arm having inspection instruments. The instrument arm has a y-arm mounted distally thereon for axially aligning the inspection instrumentation and a mounting block, a linear actuator and axial movement arm for extending the inspection instruments radially outward to operably position the inspection instruments on the piping interior. Also, the carriage has a rotation motor and gear assembly for rotating the central support and the front leg assembly with respect to the rear leg assembly so that the inspection instruments azimuthally scan the piping interior. The instrument carriage allows performance of all piping inspection operations with a minimum of moving parts, thus decreasing the likelihood of performance failure.

  13. Piping inspection carriage having axially displaceable sensor

    DOE Patents [OSTI]

    Zollinger, W.T.; Treanor, R.C.

    1994-12-06

    A pipe inspection instrument carriage is described for use with a pipe crawler for performing internal inspections of piping surfaces. The carriage has a front leg assembly, a rear leg assembly and a central support connecting the two assemblies and for mounting an instrument arm having inspection instruments. The instrument arm has a Y-arm mounted distally thereon for axially aligning the inspection instrumentation and a mounting block, a linear actuator and axial movement arm for extending the inspection instruments radially outward to operably position the inspection instruments on the piping interior. Also, the carriage has a rotation motor and gear assembly for rotating the central support and the front leg assembly with respect to the rear leg assembly so that the inspection instruments azimuthally scan the piping interior. The instrument carriage allows performance of all piping inspection operations with a minimum of moving parts, thus decreasing the likelihood of performance failure. 4 figures.

  14. Regulatory Assistance, Stakeholder Outreach, and Coastal and Marine Spatial Planning Activities in Support of Marine and Hydrokinetic Energy Deployment

    SciTech Connect (OSTI)

    Geerlofs, Simon H.; Copping, Andrea E.; Van Cleve, Frances B.; Blake, Kara M.; Hanna, Luke A.

    2011-09-30

    This fiscal year 2011 progress report summarizes activities carried out under DOE Water Power Task 2.1.7, Permitting and Planning. Activities under Task 2.1.7 address the concerns of a wide range of stakeholders with an interest in the development of the marine and hydrokinetic (MHK) energy industry, including regulatory and resource management agencies, tribes, nongovernmental organizations, and industry. Objectives for Task 2.1.7 are the following: • to work with stakeholders to streamline the MHK regulatory permitting process • to work with stakeholders to gather information on needs and priorities for environmental assessment of MHK development • to communicate research findings and directions to the MHK industry and stakeholders • to engage in spatial planning processes in order to further the development of the MHK industry. These objectives are met through three subtasks, each of which is described in this report: • 2.1.7.1—Regulatory Assistance • 2.1.7.2—Stakeholder Outreach • 2.1.7.3—Coastal and Marine Spatial Planning. As MHK industry partners work with the regulatory community and stakeholders to plan, site, permit, and license MHK technologies, they have an interest in a predictable, efficient, and transparent process. Stakeholders and regulators have an interest in processes that result in sustainable use of ocean space with minimal effects to existing ocean users. Both stakeholders and regulators have an interest in avoiding legal challenges by meeting the intent of federal, state, and local laws that govern siting and operation of MHK technologies. The intention of work under Task 2.1.7 is to understand and work to address these varied interests, reduce conflict, identify efficiencies, and ultimately reduce the regulatory costs, time, and potential environmental impacts associated with developing, siting, permitting, and deploying MHK systems.

  15. Validation of an in-flight flow visualization scheme to quantitatively measure vortical flow phenomena 

    E-Print Network [OSTI]

    Dorsett, Kenneth Merle

    1993-01-01

    A flow visualization measurement scheme was validated in flight. Strake vortex trajectories and axial core velocities were determined using pulsed smoke and high speed video. A gothic strake, operated at an angle of attack of 220 and a Reynolds...

  16. An analytical model of axial compressor off-design performance

    SciTech Connect (OSTI)

    Camp, T.R.; Horlock, J.H. . Whittle Lab.)

    1994-07-01

    An analysis is presented of the off-design performance of multistage axial-flow compressors. It is based on an analytical solution, valid for small perturbations in operating conditions from the design point, and provides an insight into the effects of choices made during the compressor design process on performance and off-design stage matching. It is shown that the mean design value of stage loading coefficient ([psi] = [Delta]h[sub 0]/U[sup 2]) has a dominant effect on off-design performance, whereas the stage-wise distribution of stage loading coefficient and the design value of flow coefficient have little influence. The powerful effects of variable stator vanes on stage-matching are also demonstrated and these results are shown to agree well with previous work. The slope of the working line of a gas turbine engine, overlaid on overall compressor characteristics, is shown to have a strong effect on the off-design stage-matching through the compressor. The model is also used to analyze design changes to the compressor geometry and to show how errors in estimates of annulus blockage, decided during the design process, have less effect on compressor performance than has previously been thought.

  17. Multi-cylinder axial stratified charging studied

    SciTech Connect (OSTI)

    Not Available

    1982-05-01

    Charge stratification can be obtained inside a noncylindrical combustion chamber of a fuel injected multi-cylinder engine by properly timing the injection event, directing the fuel spray into the inlet port, and imparting swirl to the inlet charge. A production 1.8-liter engine modified to operate as an axially stratified-charge engine showed 50% improvement in combustion stability, 3.5% lower fuel consumption, five research octane number lower octane requirement, and increased tolerance to dilute mixtures when compared with an unmodified engine.

  18. Nuclear Axial Currents in Chiral Effective Field Theory

    E-Print Network [OSTI]

    Baroni, A; Pastore, S; Schiavilla, R; Viviani, M

    2015-01-01

    Two-nucleon axial charge and current operators are derived in chiral effective field theory up to one loop. The derivation is based on time-ordered perturbation theory, and accounts for cancellations between the contributions of irreducible diagrams and the contributions due to non-static corrections from energy denominators of reducible diagrams. Ultraviolet divergencies associated with the loop corrections are isolated in dimensional regularization. The resulting axial current is finite and conserved in the chiral limit, while the axial charge requires renormalization. A complete set of contact terms for the axial charge up to the relevant order in the power counting is constructed.

  19. An analysis of axial compressor fouling and a blade cleaning method

    SciTech Connect (OSTI)

    Tarabrin, A.P.; Schurovsky, V.A.; Bodrov, A.I.; Stalder, J.P.

    1998-04-01

    The paper describes the phenomenon of axial compressor fouling due to aerosols contained in the air. Key parameters having effect on the level of fouling are determined. A mathematical model of a progressive compressor fouling using the stage-by-stage calculation method is developed. Calculation results on the influence of fouling on the compressor performance are presented. A new index of sensitivity of axial compressors to fouling is suggested. The paper gives information about Turbotect`s deposit cleaning method of compressor blading and the results of its application on an operating industrial gas turbine. Regular on-line and off-line washings of the compressor flow path made it possible to maintain a high level of engine efficiency and output.

  20. FINAL TECHNICAL REPORT: Underwater Active Acoustic Monitoring Network For Marine And Hydrokinetic Energy Projects

    SciTech Connect (OSTI)

    Stein, Peter J.; Edson, Patrick L.

    2013-12-20

    This project saw the completion of the design and development of a second generation, high frequency (90-120 kHz) Subsurface-Threat Detection Sonar Network (SDSN). The system was deployed, operated, and tested in Cobscook Bay, Maine near the site the Ocean Renewable Power Company TidGen™ power unit. This effort resulted in a very successful demonstration of the SDSN detection, tracking, localization, and classification capabilities in a high current, MHK environment as measured by results from the detection and tracking trials in Cobscook Bay. The new high frequency node, designed to operate outside the hearing range of a subset of marine mammals, was shown to detect and track objects of marine mammal-like target strength to ranges of approximately 500 meters. This performance range results in the SDSN system tracking objects for a significant duration - on the order of minutes - even in a tidal flow of 5-7 knots, potentially allowing time for MHK system or operator decision-making if marine mammals are present. Having demonstrated detection and tracking of synthetic targets with target strengths similar to some marine mammals, the primary hurdle to eventual automated monitoring is a dataset of actual marine mammal kinematic behavior and modifying the tracking algorithms and parameters which are currently tuned to human diver kinematics and classification.

  1. Feedback control of inertial microfluidics using axial control forces

    E-Print Network [OSTI]

    Christopher Prohm; Holger Stark

    2014-02-03

    Inertial microfluidics is a promising tool for many lab-on-a-chip applications. Particles in channel flows with Reynolds numbers above one undergo cross-streamline migration to a discrete set of equilibrium positions in square and rectangular channel cross sections. This effect has been used extensively for particle sorting and the analysis of particle properties. Using the lattice Boltzmann method, we determine equilibrium positions in square and rectangular cross sections and classify their types of stability for different Reynolds numbers, particle sizes, and channel aspect ratios. Our findings thereby help to design microfluidic channels for particle sorting. Furthermore, we demonstrate how an axial control force, which slows down the particles, shifts the stable equilibrium position towards the channel center. Ultimately, the particles then stay on the centerline for forces exceeding a threshold value. This effect is sensitive to particle size and channel Reynolds number and therefore suggests an efficient method for particle separation. In combination with a hysteretic feedback scheme, we can even increase particle throughput.

  2. Screening Analysis for the Environmental Risk Evaluation System Task 2.1.1.2: Evaluating Effects of Stressors Fiscal Year 2011 Progress Report - Environmental Effects of Marine and Hydrokinetic Energy

    SciTech Connect (OSTI)

    Copping, Andrea E.; Blake, Kara M.; Anderson, Richard M.; Zdanski, Laura C.; Gill, Gary A.; Ward, Jeffrey A.

    2011-09-01

    Potential environmental effects of marine and hydrokinetic (MHK) energy development are not well understood, and yet regulatory agencies are required to make decisions in spite of substantial uncertainty about environmental impacts and their long-term consequences. An understanding of risks associated with interactions between MHK installations and aquatic receptors, including animals, habitats, and ecosystems, can help define key uncertainties and focus regulatory actions and scientific studies on interactions of most concern. As a first step in developing the Pacific Northwest National Laboratory (PNNL) Environmental Risk Evaluation System (ERES), PNNL scientists conducted a preliminary risk screening analysis on three initial MHK cases. During FY 2011, two additional cases were added: a tidal project in the Gulf of Maine using Ocean Renewable Power Company TidGenTM turbines and a wave project planned for the coast of Oregon using Aquamarine Oyster surge devices. Through an iterative process, the screening analysis revealed that top-tier stressors in the two FY 2011 cases were the dynamic effects of the device (e.g., strike), accidents/disasters, and effects of the static physical presence of the device (e.g., habitat alteration). Receptor interactions with these stressors at the highest tiers of risk were dominated by threatened and endangered animals. Risk to the physical environment from changes in flow regime also ranked high. Peer review of this process and results will be conducted in early FY 2012. The ERES screening analysis provides an analysis of vulnerability of environmental receptors to stressors associated with MHK installations, probability analysis is needed to determine specific risk levels to receptors. “Risk” has two components: (1) The likelihood, or “probability”, of the occurrence of a given interaction or event, and (2) the potential “consequence” if that interaction or event were to occur. During FY 2011, the ERES screening analysis focused primarily on the second component of risk, “consequence”, with focused probability analysis for interactions where data was sufficient for probability modeling. Consequence analysis provides an assessment of vulnerability of environmental receptors to stressors associated with MHK installations. Probability analysis is needed to determine specific risk levels to receptors and requires significant data inputs to drive risk models. During FY 2011, two stressor-receptor interactions were examined for the probability of occurrence. The two interactions (spill probability due to an encounter between a surface vessel and an MHK device; and toxicity from anti-biofouling paints on MHK devices) were seen to present relatively low risks to marine and freshwater receptors of greatest concern in siting and permitting MHK devices. A third probability analysis was scoped and initial steps taken to understand the risk of encounter between marine animals and rotating turbine blades. This analysis will be completed in FY 2012.

  3. The Shaft Torque of a Tandem Axial-Piston Pump

    E-Print Network [OSTI]

    Manring, Noah D.

    The Shaft Torque of a Tandem Axial- Piston Pump Noah D. Manring Viral S. Mehta Mechanical of this study is to identify the best indexed position of two rotating groups within a tandem axial-piston pump characteristics of the pump, other vibration aspects of the machine are also expected to be reduced. In particular

  4. Effects of inlet geometries on flow recirculation in an axial-flow pump 

    E-Print Network [OSTI]

    Alpan, Kenan

    1984-01-01

    , e) hydraulic surging on the suction side, f) intense vortices with high velocities resulting with high wall static pressures at the pump inlet, g) formation of intense cavitation, h) severe pressure pulsations and noise, i) loss of energy...) mechanical seal damage. Despite elaborate research in the field of cavitation no study has been done to determine its interaction with recirculation. It is believed that they both contribute to the blade erosion. Homogenous liquids such as water are more...

  5. Torsional Alfven Waves in Solar Magnetic Flux Tubes of Axial Symmetry

    E-Print Network [OSTI]

    Murawski, K; Musielak, Z E; Srivastava, A K; Kraskiewicz, J

    2015-01-01

    Aims: Propagation and energy transfer of torsional Alfv\\'en waves in solar magnetic flux tubes of axial symmetry is studied. Methods: An analytical model of a solar magnetic flux tube of axial symmetry is developed by specifying a magnetic flux and deriving general analytical formulae for the equilibrium mass density and a gas pressure. The main advantage of this model is that it can be easily adopted to any axisymmetric magnetic structure. The model is used to simulate numerically the propagation of nonlinear Alfv\\'en waves in such 2D flux tubes of axial symmetry embedded in the solar atmosphere. The waves are excited by a localized pulse in the azimuthal component of velocity and launched at the top of the solar photosphere, and they propagate through the solar chromosphere, transition region, and into the solar corona. Results: The results of our numerical simulations reveal a complex scenario of twisted magnetic field lines and flows associated with torsional Alfv\\'en waves as well as energy transfer to t...

  6. Numerical simulation of the flow field and the lifting forces in the bristle tip region of a brush seal 

    E-Print Network [OSTI]

    Phung, Anh Ngoc

    1995-01-01

    , bristle diameter, bristle free length, seal backplate diameter, and lift-off gap. Numerical flow visualization illustrates the three-dimensional flow field, showing the circumferential, axial, and radial components of velocity near the bristle surface...

  7. Marine & Hydrokinetic Technologies

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

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Homesum_a_epg0_fpd_mmcf_m.xls" ,"Available from WebQuantity of Natural GasAdjustmentsShirleyEnergyTher i nAand DOE Safetyof Energy ThisSites |and theDepartmentPROGRAM C L E A N C

  8. Siting Methodologies for Hydrokinetics

    Energy Savers [EERE]

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Home Page on Google Bookmark EERE: Alternative Fuels Data Center Home Page on QA:QA J-E-1 SECTION J APPENDIX E LIST OF APPLICABLE DIRECTIVES Pursuant toPower WindDepartment of Energy SiteFee09

  9. Optimization of the axial power shape in pressurized water reactors

    E-Print Network [OSTI]

    Malik, Mushtaq Ahmad

    1981-01-01

    Analytical and numerical methods have been applied to find the optimum axial power profile in a PWR with respect to uranium utilization. The preferred shape was found to have a large central region of uniform power density, ...

  10. Applications of axial and radial compressor dynamic system modeling

    E-Print Network [OSTI]

    Spakovszky, Zoltán S. (Zoltán Sándor), 1972-

    2001-01-01

    The presented work is a compilation of four different projects related to axial and centrifugal compression systems. The projects are related by the underlying dynamic system modeling approach that is common in all of them. ...

  11. Design of high temperature high speed electromagnetic axial thrust bearing 

    E-Print Network [OSTI]

    Mohiuddin, Mohammad Waqar

    2002-01-01

    The National Aeronautics and Space Administration (NASA) is researching the magnetic bearings to use it as a better alternative to conventional bearings. This research was to develop an axial thrust electromagnetic bearing for high performance jet...

  12. Hyperon axial charges in two-flavor chiral perturbation theory

    SciTech Connect (OSTI)

    Jiang Fujiun; Tiburzi, Brian C.

    2009-10-01

    We use two-flavor heavy baryon chiral perturbation theory to investigate the isovector axial charges of the spin one-half hyperons. Expressions for these hyperon axial charges are derived at next-to-leading order in the chiral expansion. We utilize phenomenological and lattice QCD inputs to assess the convergence of the two-flavor theory, which appears to be best for cascades.

  13. Impact of axial diffusion on nitric oxide exchange in the lungs

    E-Print Network [OSTI]

    George, Steven C.

    Impact of axial diffusion on nitric oxide exchange in the lungs HYE-WON SHIN1 AND STEVEN C. GEORGE1, Hye-Won, and Steven C. George. Impact of axial diffusion on nitric oxide exchange in the lungs. J Appl of the lungs, but neglects axial diffusion. We incorporated axial diffusion into a one-dimensional trumpet

  14. Flow conditioner for fuel injector for combustor and method for low-NO.sub.x combustor

    DOE Patents [OSTI]

    Dutta, Partha; Smith, Kenneth O.; Ritz, Frank J.

    2013-09-10

    An injector for a gas turbine combustor including a catalyst coated surface forming a passage for feed gas flow and a channel for oxidant gas flow establishing an axial gas flow through a flow conditioner disposed at least partially within an inner wall of the injector. The flow conditioner includes a length with an interior passage opening into upstream and downstream ends for passage of the axial gas flow. An interior diameter of the interior passage smoothly reduces and then increases from upstream to downstream ends.

  15. Axially staggered seed-blanket reactor fuel module construction

    DOE Patents [OSTI]

    Cowell, Gary K. (Monroeville, PA); DiGuiseppe, Carl P. (West Mifflin, PA)

    1985-01-01

    A heterogeneous nuclear reactor of the seed-blanket type is provided wher the fissile (seed) and fertile (blanket) nuclear fuels are segregated axially within each fuel element such that fissile and fertile regions occur in an alternating pattern along the length of the fuel element. Further, different axial stacking patterns are used for the fuel elements of at least two module types such that when modules of different types are positioned adjacent to one another, the fertile regions of the modules are offset or staggered. Thus, when a module of one type is surrounded by modules of the second type the fertile regions thereof will be surrounded on all sides by fissile material. This provides enhanced neutron communication both radially and axially, thereby resulting in greater power oscillation stability than other axial arrangements. The arrangements of the fissile and fertile regions in an alternating axial manner minimizes the radial power peaking factors and provides a more optional thermal-hydraulic design than is afforded by radial arrangements.

  16. Pinch instabilities in Taylor-Couette flow Dima Shalybkov*

    E-Print Network [OSTI]

    or Hartmann number exceeds some critical value, destabilizes every flow including flows which are stable. The interval length is zero for a critical Hartmann number and increases with an increasing Hartmann number. The critical Hartmann numbers and length of the unstable axial wave number intervals are the same for every

  17. Axial symmetries in lattice QCD with Kaplan fermions

    E-Print Network [OSTI]

    Vadim Furman; Yigal Shamir

    1994-11-23

    This paper develops in detail a lattice definition of QCD based on the chiral defect fermions recently introduced by Kaplan. The revised version provides missing technical details in the proof that non-singlet axial symmetries become exact in the limit of an infinite fifth dimension. Also several minor errors are corrected.

  18. Neutrino Physics and Nuclear Axial Two-Body Interactions

    E-Print Network [OSTI]

    A. B. Balantekin; H. Yuksel

    2004-11-06

    We consider the counter-term describing isoscalar axial two-body currents in the nucleon-nucleon interaction, L1A, in the effective field theory approach. We determine this quantity using the solar neutrino data. We investigate the variation of L1A when different sets of data are used.

  19. Tube bending with axial pull and internal pressure 

    E-Print Network [OSTI]

    Agarwal, Rohit

    2004-09-30

    such as axial force and internal pressure which can be used to achieve better shape control and thickness distribution of the tube. Based on plasticity theories, an analytical model is developed to predict cross section distortion and thickness change of tubes...

  20. Crossflow instability in rotor-stator flows with throughflow , M.-P. Chauve

    E-Print Network [OSTI]

    Paris-Sud XI, Université de

    Crossflow instability in rotor-stator flows with throughflow S. Poncet , M.-P. Chauve We study. As the axial velocity profiles exhibit inflexion points, this instability is of crossflow type. From

  1. Steady-state axial pressure losses along the exterior of deformed fuel cladding: Multirod Burst Test (MRBT) bundles B-1 and B-2. [PWR; BWR

    SciTech Connect (OSTI)

    Mincey, J.F.

    1980-01-01

    The experimental and COBRA-IV computational data presented in this report confirm that increased pressure losses, induced by the steady-state axial flow of water exterior to deformed Multirod Burst Test (MRBT) bundles B-1 and B-2, may be closely predicted using a bundle-averaged approach for describing flow channel restrictions. One anomaly that was encountered using this technique occurred while modeling the B-2 flow test data near a severe channel restriction: the COBRA-IV results tended to underestimate experimental pressure losses.

  2. Axial force imparted by a current-free magnetically expanding plasma

    SciTech Connect (OSTI)

    Takahashi, Kazunori [Space Plasma, Power and Propulsion Laboratory, Research School of Physics and Engineering, Australian National University, Canberra ACT 0200 (Australia); Department of Electrical Engineering and Computer Science, Iwate University, Morioka 020-8551 (Japan); Lafleur, Trevor; Charles, Christine; Alexander, Peter; Boswell, Rod W. [Space Plasma, Power and Propulsion Laboratory, Research School of Physics and Engineering, The Australian National University, Canberra ACT 0200 (Australia)

    2012-08-15

    The axial force imparted from a magnetically expanding, current-free, radiofrequency plasma is directly measured. For an argon gas flow rate of 25 sccm and an effective rf input power of {approx}800W, a maximum force of {approx}6mN is obtained; {approx}3mN of which is transmitted via the expanding magnetic field. The measured forces are reasonably compared with a simple fluid model associated with the measured electron pressure. The model suggests that the total force is the sum of an electron pressure inside the source and a Lorentz force due to the electron diamagnetic drift current and the applied radial magnetic field. It is shown that the Lorentz force is greatest near the magnetic nozzle surface where the radial pressure gradient is largest.

  3. Effects of Electromagnetic Fields on Fish and Invertebrates Task 2.1.3: Effects on Aquatic Organisms Fiscal Year 2012 Progress Report Environmental Effects of Marine and Hydrokinetic Energy

    SciTech Connect (OSTI)

    Woodruff, Dana L.; Cullinan, Valerie I.; Copping, Andrea E.; Marshall, Kathryn E.

    2013-05-20

    Energy generated by the world’s oceans and rivers offers the potential to make substantial contributions to the domestic and global renewable energy supply. However, the marine and hydrokinetic (MHK) energy industry faces challenges related to siting, permitting, construction, and operation of pilotand commercial-scale facilities. One of the challenges is to understand the potential effects to marine organisms from electromagnetic fields, which are produced as a by-product of transmitting power from offshore to onshore locations through underwater transmission cables. This report documents the progress of the third year of research (fiscal year 2012) to investigate environmental issues associated with marine and hydrokinetic energy (MHK) generation. This work was conducted by Pacific Northwest National Laboratory (PNNL) for the U.S. Department of Energy’s (DOE’s) Office of Energy Efficiency and Renewable Energy (EERE) Wind and Water Technologies Office. The report addresses the effects of electromagnetic fields (EMFs) on selected marine species where significant knowledge gaps exist. The species studied this fiscal year included one fish and two crustacean species: the Atlantic halibut (Hippoglossus hippoglossus), Dungeness crab (Metacarcinus magister), and American lobster (Homarus americanus).

  4. Modeling for control of rotating stall in high-speed multistage axial compressors

    SciTech Connect (OSTI)

    Feulner, M.R.; Hendricks, G.J.; Paduano, J.D.

    1996-01-01

    Using a two-dimensional compressible flow representation of axial compressor dynamics, a control-theoretic input-output model is derived, which is of general utility in rotating stall/surge active control studies. The derivation presented here begins with a review of the fluid dynamic model, which is a two-dimensional stage stacking technique that accounts for blade row pressure rise, loss, and deviation as well as blade row and interblade row compressible flow. This model is extended to include the effects of the upstream and downstream geometry and boundary conditions, and then manipulated into a transfer function form that dynamically relates actuator motion to sensor measurements. Key relationships in this input-output form are then approximated using rational polynomials. Further manipulation yields an approximate model in standard form for studying active control of rotating stall and surge. As an example of high current relevance, the transfer function from an array of jet actuators to an array of static pressure sensors is derived. Numerical examples are also presented, including a demonstration of the importance of proper choice of sensor and actuator locations, as well as a comparison between sensor types. Under a variety of conditions, it was found that sensor locations near the front of the compressor or in the downstream gap are consistently the best choices, based on a quadratic optimization criterion and a specific three-stage compressor model. The modeling and evaluation procedures presented here are a first step toward a rigorous approach to the design of active control systems for high-speed axial compressors.

  5. Active stabilization of rotating stall in a three-stage axial compressor

    SciTech Connect (OSTI)

    Haynes, J.M.; Hendricks, G.J.; Epstein, A.H. . Gas Turbine Lab.)

    1994-04-01

    A three-stage, low-speed axial research compressor has been actively stabilized by damping low-amplitude circumferentially traveling waves, which can grow into rotating stall. Using a circumferential array of hot-wire sensors, and an array of high-speed individually positioned control vanes as the actuator, the first and second spatial harmonics of the compressor were stabilized down to a characteristic slope of 0.9, yielding an 8 percent increase in operating flow range. Stabilization of the third spatial harmonic did not alter the stalling flow coefficient. The actuators were also used open loop to determine the forced response behavior of the compressor. A system identification procedure applied to the forced response data then yielded the compressor transfer function. The Moore-Greitzer two-dimensional stability model was modified as suggested by the measurements to include the effect of blade row time lags on the compressor dynamics. This modified Moore-Greitzer model was then used to predict both the open and closed-loop dynamic response of the compressor. The model predictions agreed closely with the experimental results. In particular, the model predicted both the mass flow at stall without control and the design parameters needed by, and the range extension realized from, active control.

  6. Liquid metal flow encasing a magnetic cavity A. B. Hassam,a)

    E-Print Network [OSTI]

    Lathrop, Daniel P.

    Liquid metal flow encasing a magnetic cavity A. B. Hassam,a) J. F. Drake, Deepak Goel, and D. P August 1999; accepted 23 November 1999 A stationary equilibrium of a liquid metal flowing past an axial field. The liquid metal flow can be maintained by a sufficiently high pressure head. The scheme

  7. Pulsed Gradient Spin Echo Nuclear Magnetic Resonance Imaging of Diffusion in Granular Flow

    SciTech Connect (OSTI)

    Seymour, Joseph D.; Caprihan, Arvind; Altobelli, Stephen A.; Fukushima, Eiichi

    2000-01-10

    We derive the formalism to obtain spatial distributions of collisional correlation times for macroscopic particles undergoing granular flow from pulsed gradient spin echo nuclear magnetic resonance diffusion data. This is demonstrated with an example of axial motion in the shear flow regime of a 3D granular flow in a horizontal rotating cylinder at one rotation rate. (c) 2000 The American Physical Society.

  8. A Comparative Study of Modular Axial Flux Podded Generators for Marine Current Turbines

    E-Print Network [OSTI]

    Brest, Université de

    A Comparative Study of Modular Axial Flux Podded Generators for Marine Current Turbines Sofiane turbines (MCTs). Due to the submarine environment, maintenance operations are very hard, very costly current turbine, axial flux permanent magnet generator, design, optimization. Nomenclature MCT = Marine

  9. Self-Organizing Map and Axial Spatial Arrangement Topological Mapping of Alternative Designs

    E-Print Network [OSTI]

    Self-Organizing Map and Axial Spatial Arrangement Topological Mapping of Alternative Designs and Axial Spatial Arrangement:Topological Mapping of Alternative Designs properties of the objects alternatives, make it difficult to compare alternatives, and require tedious user intervention. One

  10. Design and optimization of a bi-axial vibration-driven electromagnetic...

    Office of Scientific and Technical Information (OSTI)

    Design and optimization of a bi-axial vibration-driven electromagnetic generator Citation Details In-Document Search Title: Design and optimization of a bi-axial vibration-driven...

  11. Introducing light vector and axial vector mesons in the union of chiral and heavy quark symmetries

    SciTech Connect (OSTI)

    Kamal, A.N.; Xu, Q.P. (Theoretical Physics Institute and Department of Physics, University of Alberta, Edmonton, Alberta, T6G 2J1 (Canada))

    1994-02-01

    We introduce light vector and axial vector mesons as gauge particles in a (broken) local SU[sub [ital L

  12. A Moore-Greitzer axial compressor model with spool Jan Tommy Gravdahl and Olav Egeland

    E-Print Network [OSTI]

    Gravdahl, Jan Tommy

    A Moore-Greitzer axial compressor model with spool dynamics. Jan Tommy Gravdahl and Olav Egeland applies to centrifugal compressors. It seems that the modeling and control of an axial com- pression) Table 1: Development in compressor stall/surge- control. A=Axial, C=Centrifugal, M=Modeling, C

  13. A new estimation of the axial shielding factors for multishell cylindrical shields

    E-Print Network [OSTI]

    Paperno, Eugene

    A new estimation of the axial shielding factors for multishell cylindrical shields Eugene Paperno double and multiple-shell axial magnetic shielding is obtained as a result of numerical verification of the new algorithm, a new formula describing multishell axial magnetic shielding is suggested. © 2000

  14. Damage detection for applications undergoing axial (membrane) response

    SciTech Connect (OSTI)

    Duffey, T.A. [Duffey (T.A.), Tijeras, NM (United States); Farrar, C.R.; Doebling, S.W. [Los Alamos National Lab., NM (United States)

    1997-12-01

    This paper extends and applies recently reported damage identification methods, previously utilized for flexural vibrations only, to axial-type vibrations. The methods are applied to an 8-DOF linear spring-mass system, which models a multi-degree-of-freedom axial or membrane system. The goal of the work is to detect damage (as indicated by reduction in stiffness of one or more of the elements) as well as to locate the damage elements. Two damage detection methods were investigated--the change-in-flexibility method and the damage-index method. Both were found to successfully locate the damaged element(s) for 10% reduction in element stiffness. The change-in-flexibility method indicated damage location even when only a limited number of lower modes were included.

  15. Fuel axial relocation in ballooning fuel rods. [PWR; BWR

    SciTech Connect (OSTI)

    Siefken, L.J.

    1983-01-01

    Fuel movement, in the longitudinal direction in ballooning fuel rods, shifts the position of heat generation and may cause an increase in cladding temperature in the ballooning region. This paper summarizes the axial fuel relocation data obtained in fuel rod tests conducted in the United States and the Federal Republic of Germany, describes a model for calculating fuel axial relocation, and gives a quantitative analysis of the impact of fuel relocation on cladding temperature. The amount of fuel relocation in 18 ballooned fuel rods was determined from neutron radiographs, niobium gamma decay counts, and photomicrographs. The fuel rods had burnups in the range of 0 to 35,000 MWd/t and cladding hoop strains varying from 0 to 72%.

  16. Axially staged combustion system for a gas turbine engine

    DOE Patents [OSTI]

    Bland, Robert J. (Oviedo, FL)

    2009-12-15

    An axially staged combustion system is provided for a gas turbine engine comprising a main body structure having a plurality of first and second injectors. First structure provides fuel to at least one of the first injectors. The fuel provided to the one first injector is adapted to mix with air and ignite to produce a flame such that the flame associated with the one first injector defines a flame front having an average length when measured from a reference surface of the main body structure. Each of the second injectors comprising a section extending from the reference surface of the main body structure through the flame front and having a length greater than the average length of the flame front. Second structure provides fuel to at least one of the second injectors. The fuel passes through the one second injector and exits the one second injector at a location axially spaced from the flame front.

  17. Quantifying non-axial deformations in rat myocardium 

    E-Print Network [OSTI]

    Aghassibake, Kristina Diane

    2005-02-17

    Nearly forty years after the introduction of the sliding filament theory, Zahalak expanded Huxley?s cross-bridge model from a uniaxial description of length changes in the fiber direction to a three-dimensional model that accounts for non-axial active..., and is therefore a viscoelastic material. However, in the case of cyclic loading, myocardium behaves elastically when the loading and unloading phases are considered independently; hence, 16 many investigators choose to treat myocardium as a pseudoelastic...

  18. Anisotropic flow

    E-Print Network [OSTI]

    S. A. Voloshin

    2002-11-20

    Recent experimental results on directed and elliptic flow, theoretical developments, and new techniques for anisotropic flow analysis are reviewed.

  19. Viscous throughflow modeling of axial compressor bladerows using a tangential blade force hypothesis

    SciTech Connect (OSTI)

    Gallimore, S.J.

    1998-10-01

    This paper describes the modeling of axial compressor blade rows in an axisymmetric viscous throughflow method. The basic method, which has been reported previously, includes the effects of spanwise mixing, using a turbulent diffusion model, and endwall shear within the throughflow calculation. The blades are modeled using a combination of existing two-dimensional blade performance predictions for loss and deviation away from the annulus walls and a novel approach using tangential blade forces in the endwall regions. Relatively simple assumptions about the behavior of the tangential static pressure force imposed by the blades allow the secondary deviations produced by tip clearance flows and the boundary layer flows at fixed blade ends to be calculated in the axisymmetric model. Additional losses are assigned in these regions based on the calculated deviations. The resulting method gives realistic radial distributions of loss and deviation across the whole span at both design and off-design operating conditions, providing a quick method of estimating the magnitudes of these effects in the preliminary design process. Results from the method are compared to measured data in low and high-speed compressors and multistage three-dimensional viscous CFD predictions.

  20. A study of spike and modal stall phenomena in a low-speed axial compressor

    SciTech Connect (OSTI)

    Camp, T.R.; Day, I.J.

    1998-07-01

    This paper presents a study of stall inception mechanisms in a low-speed axial compressor. Previous work has identified two common flow breakdown sequences, the first associated with a short length-scale disturbance known as a spike, and the second with a longer length-scale disturbance known as a modal oscillation. In this paper the physical differences between these two mechanisms are illustrated with detailed measurements. Experimental results are also presented that relate the occurrence of the two stalling mechanisms to the operating conditions of the compressor. It is shown that the stability criteria for the two disturbances are different: Long length-scale disturbances are related to a two-dimensional instability of the whole compression system, while short length-scale disturbances indicate a three-dimensional breakdown of the flow-field associated with high rotor incidence angles. Based on the experimental measurements, a simple model is proposed that explains the type of stall inception pattern observed in a particular compressor. Measurements from a single-stage low-speed compressor and from a multistage high-speed compressor are presented in support of the model.

  1. Sound field near hydrothermal vents on Axial Seamount, Juan de Fuca Ridge. Technical report

    SciTech Connect (OSTI)

    Little, S.A.; Stolzenbach, K.D.; Purdy, G.M.

    1990-08-10

    High-quality acoustic noise measurements were obtained by two hydrophones located 3 m and 40 m from an active hydrothermal vent on Axial Seamount, Juan de Fuca Ridge, in an effort to determine the feasibility of monitoring hydrothermal vent activity through flow noise generation. Most of the measured noise field could be attributed to ambient ocean noise sources of microseisms, distant shipping, and weather, punctuated by local ships and biological sources. Long-period, low-velocity, water/rock interface waves were detected with high amplitudes which rapidly decayed with distance from the seafloor. Detection of vent signals was hampered by unexpected spatial nonstationarity due to the shadowing effects of the calders wall. No continuous vent signals were deemed significant based on a criterion of 90% probability of detection and 5% probability of false alarm. However, a small signal near 40 Hz, with a power level of 0.0001 Pa sq/Hz was noticed on two records taken within 3 m of the Inferno black smoker. The frequency of this signal is consistent with predictions, and the power level suggests the occurrence of jet noise amplification due to convected density inhomogeneities. Keywords: Seamounts; Flow noise; Underwater acoustics; Acoustic measurement; Geothermy/noise; Ocean ridges; Underwater sound signals; Reprints; North Pacific Ocean. (EDC).

  2. Anomalous junctions characterized by Raman spectroscopy in Si{sub x}Ge{sub 1?x} nanowires with axially degraded components

    SciTech Connect (OSTI)

    Xia, Minggang, E-mail: xiamg@mail.xjtu.edu.cn [Laboratory of Nanostructure and Physics Properties, and MOE Key Laboratory for Non-equilibrium Synthesis and Modulation of Condensed Matter, School of Science, Xi'an Jiaotong University, 710049 (China); Department of Optical Information Science and Technology, School of Science, Xi'an Jiaotong University, 710049 (China); Han, Jinyun; Cheng, Zhaofang; Liang, Chunping; Zhang, Shengli [Laboratory of Nanostructure and Physics Properties, and MOE Key Laboratory for Non-equilibrium Synthesis and Modulation of Condensed Matter, School of Science, Xi'an Jiaotong University, 710049 (China); Department of Applied Physics, School of Science, Xi'an Jiaotong University, Shaanxi 710049 (China)

    2014-09-08

    The characterization of junctions in nanowires by high-resolution transmission electron microscopy with spherical aberration correction is tricky and tedious. Many disadvantages also exist, including rigorous sample preparation and structural damage inflicted by high-energy electrons. In this work, we present a simple, low-cost, and non-destructive Raman spectroscopy method of characterizing anomalous junctions in nanowires with axially degraded components. The Raman spectra of Si{sub x}Ge{sub 1?x} nanowires with axially degraded components are studied in detail using a confocal micro-Raman spectrometer. Three Raman peaks (?{sub Si–Si}?=?490?cm{sup ?1}, ?{sub Si–Ge}?=?400?cm{sup ?1}, and ?{sub Ge–Ge}?=?284?cm{sup ?1}) up-shift with increased Si content. This up-shift originates in the bond compression induced by a confined effect on the radial direction of nanowire. The anomalous junctions in Si{sub x}Ge{sub 1?x} nanowires with axially degraded components are then observed by Raman spectroscopy and verified by transmission electron microscopy energy-dispersive X-ray spectroscopy. The anomalous junctions of Si{sub x}Ge{sub 1?x} nanowires with axially degraded components are due to the vortex flow of inlet SiH{sub 4} and GeH{sub 4} gas in their synthesis. The anomalous junctions can be used as raw materials for fabricating devices with special functions.

  3. Crushing modes of aluminium tubes under axial compression

    E-Print Network [OSTI]

    Florent Henri Marc Rémy Pled; Wenyi Yan; Cui'E Wen

    2014-08-21

    A numerical study of the crushing of circular aluminium tubes with and without aluminium foam fillers has been carried out to investigate their buckling behaviours under axial compression. A crushing mode classification chart has been established for empty tubes. The influence of boundary conditions on crushing mode has also been investigated. The effect of foam filler on the crushing mode of tubes filled with foam was then examined. The predicted results would assist the design of crashworthy tube components with the preferred crushing mode with the maximum energy absorption.

  4. Axial clad strain behavior of sphere-pac fuel pins 

    E-Print Network [OSTI]

    Thomas, James Kelly

    1986-01-01

    d (Head of Depar trnent) May 1986 ABSTRACT Axial Clad Str ain Behavior of Spher e-Pac Fuel Pins (May 1986) James Kelly Thomas, B. S. , Texas AAM Univer sity Chairman of Advisor y Committee: Dn. K. L. Peddicor d Advanced nuclear f'uels ar e... being investigated to extend the lifetime and oper ating f'lexibility of fuel pins. An alter native to pellet f'uel that might satisfy these goals is spher e-pac nuclear fuel. Spher e-pac ir radiations have been per formed in the U. S. , Switzer land...

  5. Spatiotemporal focusing does not always improve axial intensity localization

    E-Print Network [OSTI]

    Cheng, Ya; Wang, Zhaohui; Li, Guihua; Zeng, Bin; He, Fei; Chu, Wei; Yao, Jinping; Qiao, Lingling

    2015-01-01

    We report on an experimental comparison on critical intensities of nonlinear self-focusing in air with conventional focusing and spatiotemporal focusing schemes. Our results show that the conventional focusing with the focal lens completely filled with the incident beam allows for the strongest axial intensity confinement against the self-focusing effect. This is because that in the high-numerical-aperture condition, the focal spot will have a compact size which results in a high focal intensity. Meanwhile, the Rayleigh length of the focused beam will be substantially shortened which efficiently postpones the onset of self-focusing.

  6. The anomalous transport of axial charge: topological vs non-topological fluctuations

    E-Print Network [OSTI]

    Ioannis Iatrakis; Shu Lin; Yi Yin

    2015-08-16

    Axial charge imbalance is an essential ingredient in novel effects associated with chiral anomaly such as chiral magnetic effects (CME). In a non-Abelian plasma with chiral fermions, local axial charge can be generated a) by topological fluctuations which would create domains with non-zero winding number b) by conventional non-topological thermal fluctuations. We provide a holographic evaluations of medium's response to dynamically generated axial charge density in hydrodynamic limit and examine if medium's response depends on the microscopic origins of axial charge imbalance. We show a local domain with non-zero winding number would induce a non-dissipative axial current due to chiral anomaly. We illustrate holographically that a local axial charge imbalance would be damped out with the damping rate related to Chern-Simon diffusive constant. By computing chiral magnetic current in the presence of dynamically generated axial charge density, we found that the ratio of CME current over the axial charge density is independent of the origin of axial charge imbalance in low frequency and momentum limit. Finally, a stochastic hydrodynamic equation of the axial charge is formulated by including both types of fluctuations.

  7. IEEE Trans. Magn., vol. 38, pp. 3324-3326, 2002 1 Abstract--Conventional analytical description of axial

    E-Print Network [OSTI]

    Paperno, Eugene

    --Amorphous Metglas material, axial (longitudinal) shielding equation, demagnetizing factor, cylindrical shields

  8. SIMULATION OF TIP LEAKAGE FLOW AROUND PARTIAL SQUEALER RIMS IN AXIAL TURBINES

    E-Print Network [OSTI]

    Camci, Cengiz

    is to protect the blade tip and cooling system from smear damage. This is a way of obtaining tighter design visualizations in extremely small geometrical features encountered near blade tip sections. After describing the control of squealer rims are described in various planes parallel to the blade tip platform on which

  9. Suction recirculation and its effects upon axial-flow pump power consumption 

    E-Print Network [OSTI]

    Prince, Tony M.

    1983-01-01

    1 Test Procedure Outline 2 Section and Pump Critical Flowrates and Speeds. 63 91 3 Power Coefficient and Reynolds Number Based on Cone Radius. 100 4 Power Coefficient and Reynolds Number Based on Surface Area. 101 5 Power Coefficient... Variation with NPSH with Q rl 54 Head Variation with NPSH with Q 2 . r2 55 Head Variation with NPSH with Q 3. r3' 120 128 129 130 131 134 135 136 CHAPTER I INTRODUCTION Pumps of different types are used to displace liquids from one location...

  10. Development of a transonic front stage of an axial flow compressor for industrial gas turbines

    SciTech Connect (OSTI)

    Katoh, Y.; Ishii, H.; Tsuda, Y.; Yanagida, M. . Mechanical Engineering Research Lab.); Kashiwabara, Y. . Dept. of Mechanical Systems Engineering)

    1994-10-01

    This paper describes the aerodynamic blade design of a highly loaded three-stage compressor, which is a model compressor for the front stage of an industrial gas turbine. Test results are presented that confirm design performance. Some surge and rotating stall measurement results are also discussed. The first stator blade in this test compressor operates in the high subsonic range at the inlet. To reduce the pressure loss due to blade surface shock waves, a shock-free airfoil is designed to replace the first stator blade in an NACA-65 airfoil in a three-stage compressor. Comparison of the performance of both blades shows that the shock-free airfoil blade reduces pressure loss. This paper also presents some experimental results for MCA (multicircular arc) airfoils, which are used for first rotor blades.

  11. Competition between modes with different axial structures in gyrotrons

    SciTech Connect (OSTI)

    Khutoryan, Eduard M.; Nusinovich, Gregory S.; Sinitsyn, Oleksandr V.

    2014-09-15

    This study was motivated by some experiments in which it was found that during the voltage rise, instead of expected excitation of a high-frequency parasitic mode, the excitation of a lower-frequency parasitic mode takes place in a certain range of voltages. For explaining this fact, the dependence of start currents of possible competing modes on the beam voltage was carried out in the cold-cavity approximation and by using the self-consistent approach. It was found that in the case of cavities, which consist of the combination of a section of constant radius waveguide and a slightly uptapered waveguide, these two approaches yield completely different results. Thus, experimentally observed excitation of the low-frequency parasitic mode can be explained by the self-consistent modification of the axial profile of the excited field, which has strong influence on the diffractive quality factor of competing modes. This modification is especially pronounced in the case of excitation of modes with many axial variations which can be excited in the region of beam interaction with the backward-wave component of such modes.

  12. Electrostatic waves in carbon nanotubes with an axial magnetic field

    SciTech Connect (OSTI)

    Abdikian, Alireza; Bagheri, Mehran

    2013-10-15

    Based on a linearized hydrodynamic model and within the quasi-static approximation, the dispersion relation of electrostatic waves propagating through single-walled carbon nanotubes subject to an axial magnetic field is theoretically explored. In the classical limit, we obtain two main possible waves which in turn are divided into two branches, a low-frequency acoustical and a high-frequency optical plasmon branch. In the quantum case, we have found that the dispersion relation is substantially modified when the electron wavelength becomes large enough compared to the propagation wavelength of the electrostatic waves in the quantum plasma. We also show that the axial magnetic field manifest itself on the perturbed electron density through the quantum term and gives rise to the propagation of the electrostatic waves within the quantum plasma. As a result, the effect of the magnetic field is pronounced in the plasma dispersion relations in such a way that their curves approach to zero when the magnetic field is weak; and for the strong magnetic field, they asymptotically meet the constant lines.

  13. Stability and angular-momentum transport of fluid flows between corotating cylinders

    E-Print Network [OSTI]

    Avila, Marc

    2012-01-01

    Turbulent transport of angular momentum is a necessary process to explain accretion in astrophysical disks. Although the hydrodynamic stability of disk-like flows has been tested in experiments, results are contradictory and suggest either laminar or turbulent flow. Direct numerical simulations reported here show that currently investigated laboratory flows are hydrodynamically unstable and become turbulent at low Reynolds numbers. The underlying instabilities stem from the axial boundary conditions, affect the flow globally and enhance angular-momentum transport.

  14. Street-based Topological Representations and Analyses for Predicting Traffic Flow in GIS

    E-Print Network [OSTI]

    Jiang, Bin

    2007-01-01

    It is well received in the space syntax community that traffic flow is significantly correlated to a morphological property of streets, which are represented by axial lines, forming a so called axial map. The correlation co-efficient (R square value) approaches 0.8 and even a higher value according to the space syntax literature. In this paper, we study the same issue using the Hong Kong street network and the Hong Kong Annual Average Daily Traffic (AADT) datasets, and find surprisingly that street-based topological representations (or street-street topologies) tend to be better representations than the axial map. In other words, vehicle flow is correlated to a morphological property of streets better than that of axial lines. Based on the finding, we suggest the street-based topological representations as an alternative GIS representation, and the topological analyses as a new analytical means for geographic knowledge discovery.

  15. Flow visualization and leakage measurements of labyrinth seals 

    E-Print Network [OSTI]

    Johnson, James Wayne

    1996-01-01

    , seals are tested over a range of Reynolds numbers, step heights, and axial offset positions (where applicable) for a fixed annular clearance. A permanent flow visualization record for each experiment is kept and analyzed in both real-time and slow motion...

  16. A new endwall model for axial compressor throughflow calculations

    SciTech Connect (OSTI)

    Dunham, J.

    1995-10-01

    It is well recognized that the endwall regions of a compressor--in which the annulus wall flow interacts with the mainstream flow--have a major influence on its efficiency and surge margin. Despite many attempts over the years to predict the very complex flow patterns in the endwall regions, current compressor design methods still rely largely on empirical estimates of the aerodynamic losses and flow angle deviations in these regions. This paper describes a new phenomenological model of the key endwall flow phenomena treated in a circumferentially averaged way. It starts from Hirsch and de Ruyck`s annulus wall boundary layer approach, but makes some important changes. The secondary vorticities arising from passage secondary flows and from tip clearance flows are calculated. Then the radial interchanges of momentum, energy, and entropy arising from both diffusion and convection are estimated. The model is incorporated into a streamline curvature program. The empirical blade force defect terms in the boundary layers are selected from cascade data. The effectiveness of the method is illustrated by comparing the predictions with experimental results on both low-speed and high-speed multistage compressors. It is found that the radial variation of flow parameters is quite well predicted, and so is the overall performance, except when significant endwall stall occurs.

  17. Three-Dimensional Tidal Flow in an Elongated, Rotating Basin CLINTON D. WINANT

    E-Print Network [OSTI]

    Winant, Clinton D.

    Three-Dimensional Tidal Flow in an Elongated, Rotating Basin CLINTON D. WINANT Integrative-dimensional tidal circulation in an elongated basin of arbitrary depth is described with a linear, constant parcels tend to corkscrew into and out of the basin in a tidal period. The axial flow is only weakly

  18. Numerical modeling of heat transfer and fluid flow in rotor-stator cavities with throughflow

    E-Print Network [OSTI]

    Boyer, Edmond

    Numerical modeling of heat transfer and fluid flow in rotor-stator cavities with throughflow S the dynamical effects from the heat transfer process. The fluid flow in an enclosed disk system with axial with heat transfer along the stator, which corresponds to the experiment of Djaoui et al. [2]. Our results

  19. Thermoacoustic mixture separation with an axial temperature gradient

    SciTech Connect (OSTI)

    Geller, Drew W; Swift, Gregory A

    2008-01-01

    The theory of thermoacoustic mixture separation is extended to include the effect of a nonzero axial temperature gradient. The analysis yields a new term in the second-order mole flux that is proportional to the temperature gradient and to the square of the volumetric velocity and is independent of the phasing of the wave. Because of this new term, thermoacoustic separation stops at a critical temperature gradient and changes direction above that gradient. For a traveling wave, this gradient is somewhat higher than that predicted by a simple four-step model. An experiment tests the theory for temperature gradients from 0 to 416 K/m in 50-50 He-Ar mixtures.

  20. Axially symmetric dissipative fluids in the quasi--static approximation

    E-Print Network [OSTI]

    Herrera, L; Ospino, J; Carot, J

    2015-01-01

    Using a framework based on the $1+3$ formalism we carry out a study on axially and reflection symmetric dissipative fluids, in the quasi--static regime. We first derive a set of invariantly defined "velocities", which allow for an inambiguous definition of the quasi--static approximation. Next we rewrite all the relevant equations in this aproximation and extract all the possible, physically relevant, consequences ensuing the adoption of such an approximation. In particular we show how the vorticity, the shear and the dissipative flux, may lead to situations where different kind of "velocities" change of sign within the fluid distribution with respect to theirs sign on the boundary surface. It is shown that states of gravitational radiation are not {\\it a priori} incompatible with the quasistatic--regime. However, any such state must last for an infinite period of time, thereby diminishing its physical relevance.

  1. Teleparallel Energy-Momentum Distribution of Static Axially Symmetric Spacetimes

    E-Print Network [OSTI]

    M. Sharif; M. Jamil Amir

    2007-04-17

    This paper is devoted to discuss the energy-momentum for static axially symmetric spacetimes in the framework of teleparallel theory of gravity. For this purpose, we use the teleparallel versions of Einstein, Landau-Lifshitz, Bergmann and M$\\ddot{o}$ller prescriptions. A comparison of the results shows that the energy density is different but the momentum turns out to be constant in each prescription. This is exactly similar to the results available in literature using the framework of General Relativity. It is mentioned here that M$\\ddot{o}$ller energy-momentum distribution is independent of the coupling constant $\\lambda$. Finally, we calculate energy-momentum distribution for the Curzon metric, a special case of the above mentioned spacetime.

  2. Axial couplings and strong decay widths of heavy hadrons

    SciTech Connect (OSTI)

    William Detmold, C.-J. David Lin, Stefan Meinel

    2012-04-01

    We calculate the axial couplings of mesons and baryons containing a heavy quark in the static limit using lattice QCD. These couplings determine the leading interactions in heavy hadron chiral perturbation theory and are central quantities in heavy quark physics, as they control strong decay widths and the light-quark mass dependence of heavy hadron observables. Our analysis makes use of lattice data at six different pion masses, 227 MeV < m{sub {pi}} < 352 MeV, two lattice spacings, a = 0.085, 0.112 fm, and a volume of (2.7 fm){sup 3}. Our results for the axial couplings are g{sub 1} = 0.449(51), g{sub 2} = 0.84(20), and g{sub 3} = 0.71(13), where g{sub 1} governs the interaction between heavy-light mesons and pions and g{sub 2,3} are similar couplings between heavy-light baryons and pions. Using our lattice result for g{sub 3}, and constraining 1/m{sub Q} corrections in the strong decay widths with experimental data for {Sigma}{sub c}{sup (*)} decays, we obtain {Gamma}[{Sigma}{sub b}{sup (*)} {yields} {Lambda}{sub b} {pi}{sup {+-}}] = 4.2(1.0), 4.8(1.1), 7.3(1.6), 7.8(1.8) MeV for the {Sigma}{sub b}{sup +}, {Sigma}{sub b}{sup -}, {Sigma}{sub b}{sup *+}, {Sigma}{sub b}{sup *-} initial states, respectively. We also derive upper bounds on the widths of the {Xi}{sub b}{sup prime(*)} baryons.

  3. Fluid flow monitoring device

    DOE Patents [OSTI]

    McKay, M.D.; Sweeney, C.E.; Spangler, B.S. Jr.

    1993-11-30

    A flow meter and temperature measuring device are described comprising a tube with a body centered therein for restricting flow and a sleeve at the upper end of the tube to carry several channels formed longitudinally in the sleeve to the appropriate axial location where they penetrate the tube to allow pressure measurements and temperature measurements with thermocouples. The high pressure measurement is made using a channel penetrating the tube away from the body and the low pressure measurement is made at a location at the widest part of the body. An end plug seals the end of the device and holes at its upper end allow fluid to pass from the interior of the tube into a plenum. The channels are made by cutting grooves in the sleeve, the grooves widened at the surface of the sleeve and then a strip of sleeve material is welded to the grooves closing the channels. Preferably the sleeve is packed with powdered graphite before cutting the grooves and welding the strips. 7 figures.

  4. Fluid flow monitoring device

    DOE Patents [OSTI]

    McKay, Mark D. (1426 Socastee Dr., North Augusta, SC 29841); Sweeney, Chad E. (3600 Westhampton Dr., Martinez, GA 30907-3036); Spangler, Jr., B. Samuel (2715 Margate Dr., Augusta, GA 30909)

    1993-01-01

    A flow meter and temperature measuring device comprising a tube with a body centered therein for restricting flow and a sleeve at the upper end of the tube to carry several channels formed longitudinally in the sleeve to the appropriate axial location where they penetrate the tube to allow pressure measurements and temperature measurements with thermocouples. The high pressure measurement is made using a channel penetrating the tube away from the body and the low pressure measurement is made at a location at the widest part of the body. An end plug seals the end of the device and holes at its upper end allow fluid to pass from the interior of the tube into a plenum. The channels are made by cutting grooves in the sleeve, the grooves widened at the surface of the sleeve and then a strip of sleeve material is welded to the grooves closing the channels. Preferably the sleeve is packed with powdered graphite before cutting the grooves and welding the strips.

  5. Investigation of Non-synchronous Vibration Mechanism for a High Speed Axial Compressor Using Delayed DES

    E-Print Network [OSTI]

    Zha, Gecheng

    Investigation of Non-synchronous Vibration Mechanism for a High Speed Axial Compressor Using compressor. DDES is a hybrid model for turbulence simulation, which uses RANS model within the wall boundary a torsion moment causing NSV. 1 Introduction Non-synchronous vibration of axial fan/compressor is a non

  6. Design Technical Briefs Valve-Plate Design for an Axial Piston

    E-Print Network [OSTI]

    Manring, Noah D.

    standby when they are used to hold pressure at low displacements. Noisy pumps also tend to wear outJournal of Mechanical Design Technical Briefs Valve-Plate Design for an Axial Piston Pump Operating advantages of using various valve-plate slot geometries within an axial piston pump. In particular, three

  7. J. Ceomag. Geoelectr., 49, 1327-1342, 1997 Seafloor Electromagnetic Measurements above Axial Seamount,

    E-Print Network [OSTI]

    Constable, Steve

    Seamount, Juan de Fuca Ridge S. C. CONSTABLE', G. S. HEINSON2, G. ANDERSON', and A. WHITE2 'Scripps be present only beneath Axial Seamount, surrounded by a resistive lithosphere of 500-50,000 u1m. The tectonic in fractures or pipes. 1. Introduction AxialSeamountlieson the Juan deFucaRidge,about 500km westof

  8. Tinkering with the axial skeleton: vertebral number variation in ecologically divergent threespine

    E-Print Network [OSTI]

    Aguirre, Windsor E.

    for publication 25 March 2014 Understanding how the vertebral column is impacted as populations adapt to differentTinkering with the axial skeleton: vertebral number variation in ecologically divergent threespine in the axial skeleton. We examined variation of vertebral number and body shape in morphologically

  9. 1 Mayne & Schneider EVALUATING AXIAL DRILLED SHAFT RESPONSE BY SEISMIC CONE

    E-Print Network [OSTI]

    Mayne, Paul W.

    1 Mayne & Schneider EVALUATING AXIAL DRILLED SHAFT RESPONSE BY SEISMIC CONE Paul W. Mayne1 , M using the results of seismic piezocone penetration tests (SCPTU) to provide continuous profiles of small to discuss the use of seismic piezocone testing for the evaluation of both axial capacity (obtained from

  10. hydrokinetic | OpenEI Community

    Open Energy Info (EERE)

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Home Page on Google Bookmark EERE: Alternative Fuels Data Center Home Page| Open Energy Information Serbia-EnhancingEtGeorgia:Illinois:WizardYatescloud Home Dc's pictureenergygrid

  11. Marine & Hydrokinetic Technologies (Fact Sheet)

    SciTech Connect (OSTI)

    Not Available

    2011-07-01

    This document described the U.S. Department of Energy's Water Power Program efforts to promote the development and deployment of advanced water power devices.

  12. Hydrokinetic Laboratory | Open Energy Information

    Open Energy Info (EERE)

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Home Page on Google Bookmark EERE: Alternative Fuels Data Center Home Page on QA:QA J-E-1 SECTION J APPENDIXsource History View NewGuam: Energyarea,MagazineTechnologies

  13. Dispersion relation and growth rate in a Cherenkov free electron laser: Finite axial magnetic field

    SciTech Connect (OSTI)

    Kheiri, Golshad; Esmaeilzadeh, Mahdi

    2013-12-15

    A theoretical analysis is presented for dispersion relation and growth rate in a Cherenkov free electron laser with finite axial magnetic field. It is shown that the growth rate and the resonance frequency of Cherenkov free electron laser increase with increasing axial magnetic field for low axial magnetic fields, while for high axial magnetic fields, they go to a saturation value. The growth rate and resonance frequency saturation values are exactly the same as those for infinite axial magnetic field approximation. The effects of electron beam self-fields on growth rate are investigated, and it is shown that the growth rate decreases in the presence of self-fields. It is found that there is an optimum value for electron beam density and Lorentz relativistic factor at which the maximum growth rate can take place. Also, the effects of velocity spread of electron beam are studied and it is found that the growth rate decreases due to the electron velocity spread.

  14. Pressure balanced drag turbine mass flow meter

    DOE Patents [OSTI]

    Dacus, Michael W. (Gilbert, AR); Cole, Jack H. (Fayetteville, AR)

    1982-01-01

    The density of the fluid flowing through a tubular member may be measured by a device comprising a rotor assembly suspended within the tubular member, a fluid bearing medium for the rotor assembly shaft, independent fluid flow lines to each bearing chamber, and a scheme for detection of any difference between the upstream and downstream bearing fluid pressures. The rotor assembly reacts to fluid flow both by rotation and axial displacement; therefore concurrent measurements may be made of the velocity of blade rotation and also bearing pressure changes, where the pressure changes may be equated to the fluid momentum flux imparted to the rotor blades. From these parameters the flow velocity and density of the fluid may be deduced.

  15. Pressure balanced drag turbine mass flow meter

    DOE Patents [OSTI]

    Dacus, M.W.; Cole, J.H.

    1980-04-23

    The density of the fluid flowing through a tubular member may be measured by a device comprising a rotor assembly suspended within the tubular member, a fluid bearing medium for the rotor assembly shaft, independent fluid flow lines to each bearing chamber, and a scheme for detection of any difference between the upstream and downstream bearing fluid pressures. The rotor assembly reacts to fluid flow both by rotation and axial displacement; therefore concurrent measurements may be made of the velocity of blade rotation and also bearing pressure changes, where the pressure changes may be equated to the fluid momentum flux imparted to the rotor blades. From these parameters the flow velocity and density of the fluid may be deduced.

  16. Reliability of steam generator tubes with axial cracks

    SciTech Connect (OSTI)

    Cizelj, L.; Mavko, B. [Jozef Stefan Inst., Ljubljana (Slovenia). Reactor Engineering Div.; Vencelj, P. [Univ. of Ljubljana (Slovenia). Faculty of Mathematics and Physics

    1996-11-01

    An approach for estimating the failure probability of tubes containing through-wall axial cracks has already been proposed by the authors. It is based on probabilistic fracture mechanics and accounts for scatter in tube geometry and material properties, scatter in residual and operational stresses responsible for crack propagation, and characteristics of nondestructive examination and plugging procedures (e.g., detection probability, sizing accuracy, human errors). Results of preliminary tests demonstrated wide applicability of this approach and triggered some improvements. The additions to the model are extensively discussed in this paper. Capabilities are demonstrated by results of analysis of steam generator no. 1 in Slovenian nuclear power plant located in Krsko after the 1992 inspection and plugging campaign. First, the number of cracked tubes and the crack length distribution were estimated using data obtained by the 100% motorized pancake coil inspection. The inspection and plugging activities were simulated in the second step to estimate the efficiency of maintenance in terms of single and multiple-tube rupture probabilities. They were calculated as a function of maximum allowable crack length. The importance of human errors and some limitations of present nondestructive examination techniques were identified. The traditional wall thickness and crack-length-based plugging criteria are compared. The crack-length-based criterion is shown to be more efficient and more safe, especially because of strong suppression effect on probability of multiple-tube rupture. The results are considered to be important for safety and maintenance of existing plants and for further research.

  17. Negative particle planar and axial channeling and channeling collimation

    SciTech Connect (OSTI)

    Carrigan, Richard A., Jr.; /Fermilab

    2009-12-01

    While information exists on high energy negative particle channeling there has been little study of the challenges of negative particle bending and channeling collimation. Partly this is because negative dechanneling lengths are relatively much shorter. Electrons are not particularly useful for investigating negative particle channeling effects because their material interactions are dominated by channeling radiation. Another important factor is that the current central challenge in channeling collimation is the proton-proton Large Hadron Collider (LHC) where both beams are positive. On the other hand in the future the collimation question might reemerge for electon-positron or muon colliders. Dechanneling lengths increase at higher energies so that part of the negative particle experimental challenge diminishes. In the article different approaches to determining negative dechanneling lengths are reviewed. The more complicated case for axial channeling is also discussed. Muon channeling as a tool to investigate dechanneling is also discussed. While it is now possible to study muon channeling it will probably not illuminate the study of negative dechanneling.

  18. Axial magnetic field and toroidally streaming fast ions in the dense plasma focus are natural consequences of conservation laws in the curved axisymmetric geometry of the current sheath

    SciTech Connect (OSTI)

    Auluck, S. K. H.

    2014-10-15

    Direct measurement of axial magnetic field in the PF-1000 dense plasma focus (DPF), and its reported correlation with neutron emission, call for a fresh look at previous reports of existence of axial magnetic field component in the DPF from other laboratories, and associated data suggesting toroidal directionality of fast ions participating in fusion reactions, with a view to understand the underlying physics. In this context, recent work dealing with application of the hyperbolic conservation law formalism to the DPF is extended in this paper to a curvilinear coordinate system, which reflects the shape of the DPF current sheath. Locally unidirectional shock propagation in this coordinate system enables construction of a system of 7 one-dimensional hyperbolic conservation law equations with geometric source terms, taking into account all the components of magnetic field and flow velocity. Rankine-Hugoniot jump conditions for this system lead to expressions for the axial magnetic field and three components of fluid velocity having high ion kinetic energy.

  19. Axial current generation by P-odd domains in QCD matter

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

    Iatrakis, Ioannis; Yin, Yi; Lin, Shu

    2015-06-23

    The dynamics of topological domains which break parity (P) and charge-parity (CP) symmetry of QCD are studied. We derive in a general setting that those local domains will generate an axial current and quantify the strength of the induced axial current. Thus, our findings are verified in a top-down holographic model. The relation between the real time dynamics of those local domains and the chiral magnetic field is also elucidated. We finally argue that such an induced axial current would be phenomenologically important in a heavy-ion collisions experiment.

  20. Singlet axial-vector coupling constant of the nucleon in QCD without instantons

    E-Print Network [OSTI]

    Janardan P. Singh

    2015-07-19

    We have analyzed axial-vector current-current correlation functions between one-nucleon states to calculate the singlet axial-vector coupling constant of the nucleon. The octet-octet and the octet-singlet current correlators, investigated in this work, do not require any use of instanton effects. The QCD and hadronic parameters used for the evaluation of correlators have been varied by (10 - 20)%. The value of the singlet axial-vector coupling constant of the nucleon obtained from this analysis is consistent with its current determination from experiments and QCD theory.

  1. The Flow of Newtonian Fluids in Axisymmetric Corrugated Tubes

    E-Print Network [OSTI]

    Taha Sochi

    2010-06-08

    This article deals with the flow of Newtonian fluids through axially-symmetric corrugated tubes. An analytical method to derive the relation between volumetric flow rate and pressure drop in laminar flow regimes is presented and applied to a number of simple tube geometries of converging-diverging nature. The method is general in terms of fluid and tube shape within the previous restrictions. Moreover, it can be used as a basis for numerical integration where analytical relations cannot be obtained due to mathematical difficulties.

  2. The Flow of Newtonian Fluids in Axisymmetric Corrugated Tubes

    E-Print Network [OSTI]

    Sochi, Taha

    2010-01-01

    This article deals with the flow of Newtonian fluids through axially-symmetric corrugated tubes. An analytical method to derive the relation between volumetric flow rate and pressure drop in laminar flow regimes is presented and applied to a number of simple tube geometries of converging-diverging nature. The method is general in terms of fluid and tube shape within the previous restrictions. Moreover, it can be used as a basis for numerical integration where analytical relations cannot be obtained due to mathematical difficulties.

  3. Effects of nonaxisymmetric tip clearance on axial compressor performance and stability

    SciTech Connect (OSTI)

    Graf, M.B.; Wong, T.S.; Greitzer, E.M.; Marble, F.E.; Tan, C.S.; Shin, H.W.; Wisler, D.C.

    1998-10-01

    The effects of circumferentially nonuniform tip clearance on axial compressor performance and stability have been investigated experimentally and analytically. A theoretical model for compressor behavior with nonaxisymmetric tip clearance has been developed and used to design a series of first-of-a-kind experiments on a four-stage, low-speed compressor. The experiments and computational results together show clearly the central physical features and controlling parameters of compressor response to nonaxisymmetric tip clearance. It was found that the loss in stall margin was more severe than that estimated based on average clearance. The stall point was, in fact, closer to that obtained with uniform clearance at the maximum clearance level. The circumferential length scale of the tip clearance (and accompanying flow asymmetry) was an important factor in determining the stall margin reduction. For the same average clearance, the loss in peak pressure rise was 50 percent higher for an asymmetry with fundamental wavelength equal to the compressor circumference than with wavelength equal to one-half the circumference. The clearance asymmetry had much less of an effect on peak efficiency; the measured maximum efficiency decrease obtained was less than 0.4 percent compared to the 8 percent decrease in peak pressure rise due to the asymmetric clearance. The efficiency penalty due to nonaxisymmetric tip clearance was thus close to that obtained with a uniform clearance at the circumferentially averaged level. The theoretical model accurately captured the decreases in both steady-state pressure rise and stable operating range which are associated with clearance asymmetry.

  4. Flow chamber

    DOE Patents [OSTI]

    Morozov, Victor (Manassas, VA)

    2011-01-18

    A flow chamber having a vacuum chamber and a specimen chamber. The specimen chamber may have an opening through which a fluid may be introduced and an opening through which the fluid may exit. The vacuum chamber may have an opening through which contents of the vacuum chamber may be evacuated. A portion of the flow chamber may be flexible, and a vacuum may be used to hold the components of the flow chamber together.

  5. The effect of nonuniform axial heat flux distribution on the critical heat flux

    E-Print Network [OSTI]

    Todreas, Neil E.

    1965-01-01

    A systematic experimental and analytic investigation of the effect of nonuniform axial heat flux distribution on critical heat rilux was performed with water in the quality condition. Utilizing a model which ascribes the ...

  6. REVIEW OF SCIENTIFIC INSTRUMENTS 83, 103106 (2012) Practical axial optical trapping

    E-Print Network [OSTI]

    Regan, Lynne

    2012-01-01

    REVIEW OF SCIENTIFIC INSTRUMENTS 83, 103106 (2012) Practical axial optical trapping A. H. Mack,1- fer a number of practical advantages: first, a range of meth- ods is available to tether large numbers

  7. Designing for forces : an early-stage design program for axial-force structures

    E-Print Network [OSTI]

    Jordan, Alexander D. W. (Alexander David Weigert)

    2011-01-01

    Structures that carry most of their load through the axial forces of tension or compression are more materially efficient than standard structures. However, they are not as straightforward to design since the forces in the ...

  8. Axially staggered seed-blanket reactor-fuel-module construction. [LWBR

    DOE Patents [OSTI]

    Cowell, G.K.; DiGuiseppe, C.P.

    1982-10-28

    A heterogeneous nuclear reactor of the seed-blanket type is provided wherein the fissile (seed) and fertile (blanket) nuclear fuels are segregated axially within each fuel element such that fissile and fertile regions occur in an alternating pattern along the length of the fuel element. Further, different axial stacking patterns are used for the fuel elements of at least two module types such that when modules of different types are positioned adjacent to one another, the fertile regions of the modules are offset or staggered. Thus, when a module of one type is surrounded by modules of the second type the fertile regions thereof will be surrounded on all sides by fissile material. This provides enhanced neutron communication both radially and axially, thereby resulting in greater power oscillation stability than other axial arrangements.

  9. An improved blade passage model for estimating off-design axial compressor performance

    E-Print Network [OSTI]

    Brand, Maximilian Lewis

    2013-01-01

    Accurate estimates of multistage axial compressor performance at off-design operating conditions are essential to the determination of key performance metrics of aircraft gas turbine engines, such as fuel burn, thrust ...

  10. A co-axially configured submillimeter spectrometer and investigations of hydrogen bound molecular complexes 

    E-Print Network [OSTI]

    McElmurry, Blake Anthony

    2009-05-15

    The development of a co-axially configured submillimeter spectrometer is reported. The spectrometer has been constructed to observe molecular complexes that exhibit non-covalent interactions with energies much less than ...

  11. Cladding axial elongation models for FRAP-T6. [PWR; BWR

    SciTech Connect (OSTI)

    Shah, V.N.; Carlson, E.R.; Berna, G.A.

    1983-01-01

    This paper presents a description of the cladding axial elongation models developed at the Idaho National Engineering Laboratory (INEL) for use by the FRAP-T6 computer code in analyzing the response of fuel rods during reactor transients in light water reactors (LWR). The FRAP-T6 code contains models (FRACAS-II subcode) that analyze the structural response of a fuel rod including pellet-cladding-mechanical-interaction (PCMI). Recently, four models were incorporated into FRACAS-II to calculate cladding axial deformation: (a) axial PCMI, (b) trapped fuel stack, (c) fuel relocation, and (d) effective fuel thermal expansion. Comparisons of cladding axial elongation measurements from two experiments with the corresponding FRAP-T6 calculations are presented.

  12. Experimental demonstration of polarization-assisted transverse and axial optical superresolution

    E-Print Network [OSTI]

    Teich, Malvin C.

    , coaxial Gaussian beams with axially offset foci F1 and F2 are superposed. Since the Gouy phase for each of Electrical and Computer Engineering, Quantum Imaging Laboratory, Boston University, 8 Saint Marys Street

  13. High-Efficiency Deflection of High-Energy Protons through Axial...

    Office of Scientific and Technical Information (OSTI)

    High-Efficiency Deflection of High-Energy Protons through Axial Channeling in a Bent Crystal Citation Details In-Document Search Title: High-Efficiency Deflection of High-Energy...

  14. Time history analysis of axial forces (Pass Through Forces) at joints in a braced frame

    E-Print Network [OSTI]

    Paschini, Vincent

    2012-01-01

    As buildings keep getting taller, traditional braced lateral systems take more loads. This generates a phenomenon at every joint of a frame called "Pass Through Force". Pass through forces come from the transfer of axial ...

  15. Single- and Two-Phase Diversion Cross-Flows Between Triangle Tight Lattice Rod Bundle Subchannels - Data on Flow Resistance and Interfacial Friction Coefficients for the Cross-Flow

    SciTech Connect (OSTI)

    Tatsuya Higuchi; Akimaro Kawahara; Michio Sadatomi; Hiroyuki Kudo [Kumamoto University, 39-1, Kurokami 2-chome, Kumamoto 860-8555 (Japan)

    2006-07-01

    Single- and two-phase diversion cross-flows arising from the pressure difference between tight lattice subchannels are our concern in this study. In order to obtain a correlation of the diversion cross-flow, we conducted adiabatic experiments using a vertical multiple-channel with two subchannels simplifying the triangle tight lattice rod bundle for air-water flows at room temperature and atmospheric pressure. In the experiments, data were obtained on the axial variations in the pressure difference between the subchannels, the ratio of flow rate in one subchannel to the whole channel, the void fraction in each subchannel for slug-churn and annular flows in two-phase flow case. These data were analyzed by use of a lateral momentum equation based on a two-fluid model to determine both the cross-flow resistance coefficient between liquid phase and channel wall and the gas-liquid interfacial friction coefficient. The resulting coefficients have been correlated in a way similar to that developed for square lattice subchannel case by Kano et al. (2002); the cross-flow resistance coefficient data can be well correlated with a ratio of the lateral velocity due to the cross-flow to the axial one irrespective of single- and two-phase flows; the interfacial friction coefficient data were well correlated with a Reynolds number, which is based on the relative velocity between gas and liquid cross-flows as the characteristic velocity. (authors)

  16. Geological flows

    E-Print Network [OSTI]

    Yu. N. Bratkov

    2008-11-19

    In this paper geology and planetology are considered using new conceptual basis of high-speed flow dynamics. Recent photo technics allow to see all details of a flow, 'cause the flow is static during very short time interval. On the other hand, maps and images of many planets are accessible. Identity of geological flows and high-speed gas dynamics is demonstrated. There is another time scale, and no more. All results, as far as the concept, are new and belong to the author. No formulae, pictures only.

  17. Flow regimes

    SciTech Connect (OSTI)

    Liles, D.R.

    1982-01-01

    Internal boundaries in multiphase flow greatly complicate fluid-dynamic and heat-transfer descriptions. Different flow regimes or topological configurations can have radically dissimilar interfacial and wall mass, momentum, and energy exchanges. To model the flow dynamics properly requires estimates of these rates. In this paper the common flow regimes for gas-liquid systems are defined and the techniques used to estimate the extent of a particular regime are described. Also, the current computer-code procedures are delineated and introduce a potentially better method is introduced.

  18. Electron Diamagnetic Effect on Axial Force in an Expanding Plasma: Experiments and Theory

    SciTech Connect (OSTI)

    Takahashi, Kazunori [Space Plasma, Power and Propulsion Laboratory, Research School of Physics and Engineering, Australian National University, Canberra ACT 0200 (Australia); Department of Electrical Engineering and Computer Science, Iwate University, Morioka 020-8551 (Japan); Lafleur, Trevor; Charles, Christine; Alexander, Peter; Boswell, Rod W. [Space Plasma, Power and Propulsion Laboratory, Research School of Physics and Engineering, Australian National University, Canberra ACT 0200 (Australia)

    2011-12-02

    The axial force imparted from a magnetically expanding current-free plasma is directly measured for three different experimental configurations and compared with a two-dimensional fluid theory. The force component solely resulting from the expanding field is directly measured and identified as an axial force produced by the azimuthal current due to an electron diamagnetic drift and the radial component of the magnetic field. The experimentally measured forces are well described by the theory.

  19. BEC-BCS crossover driven by the axial anomaly in the NJL model

    E-Print Network [OSTI]

    Abuki, Hiroaki; Hatsuda, Tetsuo; Yamamoto, Naoki

    2010-01-01

    We study the QCD phase structure in the three-flavor Nambu--Jona-Lasinio model, incorporating the chiral-diquark interplay due to the axial anomaly. We demonstrate that for a certain range of model parameters, the low temperature critical point predicted by a Ginzburg-Landau analysis appears in the phase diagram. In addition, we show that the axial anomaly presents a new scenario for a possible BEC-BCS crossover in the color-flavor locked phase of QCD.

  20. Relativistic Hartree-Fock-Bogoliubov Theory With Density Dependent Meson Couplings in Axial Symmetry

    SciTech Connect (OSTI)

    Ebran, J.-P.; Khan, E.; Arteaga, D. Pena; Grasso, M.; Vretenar, D.

    2009-08-26

    Most nuclei on the nuclear chart are deformed, and the development of new RIB facilities allows the study of exotic nuclei near the drip lines where a successful theoretical description requires both realistic pairing and deformation approaches. Relativistic Hartree-Fock-Bogoliubov model taking into account axial deformation and pairing correlations is introduced. Preliminary illustrative results with density dependent meson-nucleon couplings in axial symmetry will be discussed.

  1. Weak axial nuclear heavy meson exchange currents and interactions of solar neutrinos with deuterons

    E-Print Network [OSTI]

    B. Mosconi; P. Ricci; E. Truhlik

    2007-02-28

    Starting from the axial heavy meson exchange currents, constructed earlier in conjunction with the Bethe--Salpeter equation, we first present the axial $\\rho$--, $\\omega$-- and $a_1$ meson exchange Feynman amplitudes that satisfy the partial conservation of the axial current. Employing these amplitudes, we derive the corresponding weak axial heavy meson exchange currents in the leading order in the 1/M expansion ($M$ is the nucleon mass), suitable for the nuclear physics calculations beyond the threshold energies and with wave functions obtained by solving the Schr\\"odinger equation with one--boson exchange potentials. The constructed currents obey the nuclear form of the partial conservation of the axial current. We apply the space component of these currents in calculations of the cross sections for the disintegration of deuterons by low energy (anti)neutrinos. The deuteron and the final state nucleon--nucleon wave functions are derived (i) from a variant of the OBEPQB potential, and (ii) from the Nijmegen 93 and Nijmegen I nucleon-nucleon interaction. The extracted values of the constant $L_{1, A}$, entering the axial exchange currents of the pionless effective field theory, are in a reasonable agreement with its value predicted by the dimensional analysis.

  2. Neutron tomography of axially symmetric objects using 14 MeV neutrons from a portable neutron generator

    SciTech Connect (OSTI)

    Andersson, P. Andersson-Sunden, E.; Sjöstrand, H.; Jacobsson-Svärd, S.

    2014-08-01

    In nuclear boiling water reactor cores, the distribution of water and steam (void) is essential for both safety and efficiency reasons. In order to enhance predictive capabilities, void distribution assessment is performed in two-phase test-loops under reactor-relevant conditions. This article proposes the novel technique of fast-neutron tomography using a portable deuterium-tritium neutron generator to determine the time-averaged void distribution in these loops. Fast neutrons have the advantage of high transmission through the metallic structures and pipes typically concealing a thermal-hydraulic test loop, while still being fairly sensitive to the water/void content. However, commercially available fast-neutron generators also have the disadvantage of a relatively low yield and fast-neutron detection also suffers from relatively low detection efficiency. Fortunately, some loops are axially symmetric, a property which can be exploited to reduce the amount of data needed for tomographic measurement, thus limiting the interrogation time needed. In this article, three axially symmetric test objects depicting a thermal-hydraulic test loop have been examined; steel pipes with outer diameter 24 mm, thickness 1.5 mm, and with three different distributions of the plastic material POM inside the pipes. Data recorded with the FANTOM fast-neutron tomography instrument have been used to perform tomographic reconstructions to assess their radial material distribution. Here, a dedicated tomographic algorithm that exploits the symmetry of these objects has been applied, which is described in the paper. Results are demonstrated in 20 rixel (radial pixel) reconstructions of the interior constitution and 2D visualization of the pipe interior is demonstrated. The local POM attenuation coefficients in the rixels were measured with errors (RMS) of 0.025, 0.020, and 0.022 cm{sup ?1}, solid POM attenuation coefficient. The accuracy and precision is high enough to provide a useful indication on the flow mode, and a visualization of the radial material distribution can be obtained. A benefit of this system is its potential to be mounted at any axial height of a two-phase test section without requirements for pre-fabricated entrances or windows. This could mean a significant increase in flexibility of the void distribution assessment capability at many existing two-phase test loops.

  3. ANALYSIS OF THE AXIAL GAP VS FIBERBOARD MOISTURE CONTENT IN A 9975 SHIPPING PACKAGE

    SciTech Connect (OSTI)

    Daugherty, W.

    2013-09-30

    The fiberboard assembly within a 9975 shipping package contains a modest amount of moisture, which can migrate to the cooler regions of the package when an internal heat load is present. Typically, this leads to increased moisture levels in the bottom fiberboard layers, along with elevated chloride levels which can leach from the fiberboard. Concerns have been raised that this condition could lead to corrosion of the stainless steel drum. It has been postulated that checking the axial gap at the top of the package against the current 1 inch maximum criterion provides a sufficient indication regarding the integrity of the fiberboard and drum. This report estimates the increase in axial gap that might be expected for a given moisture increase in the bottom fiberboard layers, and the likelihood that the increase will create a nonconforming condition that will lead to identification of the moisture increase. Using data relating the fiberboard moisture content with the degree of compaction under load, the present analysis indicates that the axial gap will increase by 0.282 inch as the bottom fiberboard layers approach the saturation point. This increase will cause approximately 58% of packages with otherwise nominal package component dimensions to fail the axial gap criterion, based on a survey of axial gap values recorded in K-Area surveillance activities. As the moisture content increases above saturation, the predicted increase in axial gap jumps to 0.405 inch, which would result in 92% or more of all packages failing the axial gap criterion. The data and analysis described in this report are specific to cane fiberboard. While it is expected that softwood fiberboard will behave similarly, such behavior has not yet been demonstrated.

  4. SOUND TRANSMISSION IN SLOWLY VARYING CIRCULAR AND ANNULAR LINED DUCTS WITH FLOW a

    E-Print Network [OSTI]

    Eindhoven, Technische Universiteit

    SOUND TRANSMISSION IN SLOWLY VARYING CIRCULAR AND ANNULAR LINED DUCTS WITH FLOW a S.W. Rienstra/CEAS Aeroacoustics Conference, June 2­4, 1998, Toulouse ABSTRACT Sound transmission through straight circular ducts by a modal expansion. A natural ex­ tension for ducts with axially slowly varying properties (diameter

  5. Three-dimensional turbulent swirling flow in a cylinder: Experiments and computations

    E-Print Network [OSTI]

    Gupta, Amit

    and an axial exhaust called a vortex finder tube. Due to the centrif- ugal action of the fluid from fluid forms an inner vortex and exits through the vortex finder tube located at the top. The out- flow through the cone is usually called the underflow and that through the vortex finder tube the overflow

  6. Axial seal system for a gas turbine steam-cooled rotor

    DOE Patents [OSTI]

    Mashey, Thomas Charles (Anderson, SC)

    2002-01-01

    An axial seal assembly is provided at the interface between adjacent wheels and spacers of a gas turbine rotor and disposed about tubes passing through openings in the rotor adjacent the rotor rim and carrying a thermal medium. Each seal assembly includes a support bushing for supporting a land of the thermal medium carrying tube, an axially registering seat bushing disposed in the opposed opening and a frustoconical seal between the seal bushing and seat. The seal bushing includes a radial flange having an annular recess for retaining the outer diameter edge of the seal, while the seat bushing has an axially facing annular surface forming a seat for engagement by the inner diameter edge of the seal.

  7. Flexural support member having a high ratio of lateral-to-axial stiffness

    DOE Patents [OSTI]

    Haas, W.M.B.

    1983-06-23

    A convoluted flexible support structure is provided which is capable of supplying a lateral to axial spring rate in excess of 1000 to 1. A support member in the form of a steel disc having a specified number of rather large radius, concentric convolutions and a thickness in the range of from about 0.01 to 0.02 inch has an axial stiffness of about 50 pounds/inch while the lateral stiffness is about 100,000 pounds/inch. The support member may be used to support a vibration device where the lateral motion of the vibrator must be highly restricted while providing relatively free axial displacement of about +-0.25 inch.

  8. The development of CACTUS : a wind and marine turbine performance simulation code.

    SciTech Connect (OSTI)

    Barone, Matthew Franklin; Murray, Jonathan

    2010-12-01

    CACTUS (Code for Axial and Cross-flow TUrbine Simulation) is a turbine performance simulation code, based on a free wake vortex method, under development at Sandia National Laboratories (SNL) as part of a Department of Energy program to study marine hydrokinetic (MHK) devices. The current effort builds upon work previously done at SNL in the area of vertical axis wind turbine simulation, and aims to add models to handle generic device geometry and physical models specific to the marine environment. An overview of the current state of the project and validation effort is provided.

  9. Production of low axial energy spread ion beams with multicusp sources

    SciTech Connect (OSTI)

    Lee, Y.H.Y.

    1998-05-01

    Multicusp ion sources are capable of producing ions with low axial energy spread which are necessary in applications such as: ion projection lithography (IPL) and focused ion beams for the next generation lithographic tools and nuclear science experiments such as radioactive ion beam production. The axial ion energy spread for multicusp source is approximately 6 eV which is too large for IPL and radioactive ion beam applications. The addition of a magnetic filter which consists of a pair of permanent magnets to the multicusp source reduces the energy spread considerably. The reduction is due to the improvement in the uniformity of the axial plasma potential distribution in the discharge region. Axial ion energy spread of the filament driven ion source has been measured using three different techniques. In all cases, it was found to be less than 2 eV. Energy spread of the radio frequency (RF) driven source has also been explored, and it was found to be less than 3 eV with the proper RF-shielding. A new multicusp source configuration has been designed and constructed to further reduce the energy spread. To achieve a more uniform axial plasma potential distribution, a cylindrical magnetic filter has been designed and constructed for a 2-cm-diameter source. This new source configuration, the co-axial source, is new in its kind. The energy spread in this source has been measured to be a record low of 0.6 eV. Because of the novelty of this device, some plasma parameters inside the source have been studied. Langmuir probe has been used to measure the plasma potential, the electron temperature and the density distribution.

  10. An axially propagating two-stream instability in the Hall thruster plasma

    SciTech Connect (OSTI)

    Tsikata, S., E-mail: sedina.tsikata@cnrs-orleans.fr [ICARE, CNRS (UPR 3021), 1C ave. de la Recherche Scientifique, 45071 Orléans (France); Cavalier, J. [Institute of Plasma Physics ASCR, Prague (Czech Republic); Héron, A. [CPHT, CNRS (UMR 7644), Ecole Polytechnique, Route de Saclay, 91128 Palaiseau (France); Honoré, C.; Grésillon, D. [LPP, CNRS (UMR 7648), Ecole Polytechnique-Univ. Paris-Sud-UPMC Univ. Paris 06, Route de Saclay, 91128 Palaiseau (France); Lemoine, N.; Coulette, D. [IJL, CNRS (UMR 7198), Université de Lorraine, BP 70239, 54506 Vandoeuvre-lès-Nancy (France)

    2014-07-15

    Collective Thomson scattering experiments reveal the presence of high-frequency, axial electron density fluctuations at millimetric wavelengths in the Hall thruster plasma. The properties of these fluctuations are investigated experimentally and via linear kinetic theory. The relative drift of electrons and ions in the axial direction is found to be insufficient to cause excitation of the observed mode. Instead, the mode is determined to be a two-stream instability arising due to the velocity difference between singly and doubly charged ion populations in the plume.

  11. Experimental on two sensors combination used in horizontal pipe gas-water two-phase flow

    SciTech Connect (OSTI)

    Wu, Hao; Dong, Feng

    2014-04-11

    Gas-water two phase flow phenomenon widely exists in production and living and the measurement of it is meaningful. A new type of long-waist cone flow sensor has been designed to measure two-phase mass flow rate. Six rings structure of conductance probe is used to measure volume fraction and axial velocity. The calibration of them have been made. Two sensors have been combined in horizontal pipeline experiment to measure two-phase flow mass flow rate. Several model of gas-water two-phase flow has been discussed. The calculation errors of total mass flow rate measurement is less than 5% based on the revised homogeneous flow model.

  12. Flow cytometer

    DOE Patents [OSTI]

    Van den Engh, G.

    1995-11-07

    A Faraday cage is described which encloses the flow chamber of a cytometer. Ground planes associated with each field deflection plate inhibit electric fields from varying the charge on designated events/droplets and further concentrates. They also increase forces applied to a passing charged event for accurate focus while concomitantly inhibiting a potential shock hazard. 4 figs.

  13. OPPDIF: A Fortran program for computing opposed-flow diffusion flames

    SciTech Connect (OSTI)

    Lutz, A.E.; Kee, R.J.; Grcar, J.F.; Rupley, F.M.

    1997-05-01

    OPPDIF is a Fortran program that computes the diffusion flame between two opposing nozzles. A similarity transformation reduces the two-dimensional axisymmetric flow field to a one-dimensional problem. Assuming that the radial component of velocity is linear in radius, the dependent variables become functions of the axial direction only. OPPDIF solves for the temperature, species mass fractions, axial and radial velocity components, and radial pressure gradient, which is an eigenvalue in the problem. The TWOPNT software solves the two-point boundary value problem for the steady-state form of the discretized equations. The CHEMKIN package evaluates chemical reaction rates and thermodynamic and transport properties.

  14. Axial obliquity control on the greenhouse carbon budget through middle-to high-latitude reservoirs

    E-Print Network [OSTI]

    Meyers, Stephen R.

    Axial obliquity control on the greenhouse carbon budget through middle- to high-latitude reservoirs for past greenhouse climates. Carbon-isotope data indicate systematic, million-year-scale transfers-stable character, they might have provided an important control on the dynamics and stability of the greenhouse

  15. Nucleon axial charge from quenched lattice QCD with domain wall fermions

    E-Print Network [OSTI]

    Shoichi Sasaki; Kostas Orginos; Shigemi Ohta; Tom Blum; for the RBCK Collaboration

    2003-07-18

    We present a quenched lattice calculation of the nucleon isovector vector and axial-vector charges gV and gA. The chiral symmetry of domain wall fermions makes the calculation of the nucleon axial charge particularly easy since the Ward-Takahashi identity requires the vector and axial-vector currents to have the same renormalization, up to lattice spacing errors of order O(a^2). The DBW2 gauge action provides enhancement of the good chiral symmetry properties of domain wall fermions at larger lattice spacing than the conventional Wilson gauge action. Taking advantage of these methods and performing a high statistics simulation, we find a significant finite volume effect between the nucleon axial charges calculated on lattices with (1.2 fm)^3 and (2.4 fm)^3 volumes (with lattice spacing, a, of about 0.15 fm). On the large volume we find gA = 1.212 +/- 0.027(statistical error) +/- 0.024(normalization error). The quoted systematic error is the dominant (known) one, corresponding to current renormalization. We discuss other possible remaining sources of error. This theoretical first principles calculation, which does not yet include isospin breaking effects, yields a value of gA only a little bit below the experimental one, 1.2670 +/- 0.0030.

  16. Vertical deformation monitoring at Axial Seamount since its 1998 eruption using deep-sea pressure sensors

    E-Print Network [OSTI]

    Chadwick, Bill

    Vertical deformation monitoring at Axial Seamount since its 1998 eruption using deep-sea pressure geodesy; bottom pressure recorder 1. Introduction The purpose of vertical deformation monitoring at active.W. Chadwick). Journal of Volcanology and Geothermal Research 150 (2006) 313­327 www

  17. Single and Tandem Axial p-i-n Nanowire Photovoltaic Devices

    E-Print Network [OSTI]

    Xie, Xiaoliang Sunney

    Single and Tandem Axial p-i-n Nanowire Photovoltaic Devices Thomas J. Kempa,, Bozhi Tian,, Dong Rip-i-n+-p+-i-n silicon nanowire (SiNW) photovoltaic elements. Scanning electron microscopy images of selectively etched. Finally, a novel single SiNW tandem solar cell consisting of synthetic integration of two photovoltaic

  18. Novel LINAC II electrode geometry to create an axial field in a multipole ion guide.

    E-Print Network [OSTI]

    Ens, Werner

    and determines the upper m/z transmission limit. A conventional LINAC has a quadrupolar DC field distortion while like the LINAC(SCIEX) suffer from a reduced mass transmission window. A wide transmission window. The axial field is created by applying the same DC potential UL to all four T-shaped electrodes

  19. Resonance behavior of liquid bridges under axial and lateral oscillating total body forces

    E-Print Network [OSTI]

    Taylor, Philip L.

    bridges that are magnetically levitated in air against gravity are subjected to either axial or lateral of the technique of time-varying magnetic levitation is that problems associated with the influence of the outer is a simple configuration that is ideal for the study of static properties (Meseguer 1983; Meseguer and Sanz

  20. Gravitational waves from a test particle scattered by a neutron star: Axial mode case

    E-Print Network [OSTI]

    Kazuhiro Tominaga; Motoyuki Saijo; Kei-ichi Maeda

    1999-09-20

    Using a metric perturbation method, we study gravitational waves from a test particle scattered by a spherically symmetric relativistic star. We calculate the energy spectrum and the waveform of gravitational waves for axial modes. Since metric perturbations in axial modes do not couple to the matter fluid of the star, emitted waves for a normal neutron star show only one peak in the spectrum, which corresponds to the orbital frequency at the turning point, where the gravitational field is strongest. However, for an ultracompact star (the radius $R \\lesssim 3M$), another type of resonant periodic peak appears in the spectrum. This is just because of an excitation by a scattered particle of axial quasinormal modes, which were found by Chandrasekhar and Ferrari. This excitation comes from the existence of the potential minimum inside of a star. We also find for an ultracompact star many small periodic peaks at the frequency region beyond the maximum of the potential, which would be due to a resonance of two waves reflected by two potential barriers (Regge-Wheeler type and one at the center of the star). Such resonant peaks appear neither for a normal neutron star nor for a Schwarzschild black hole. Consequently, even if we analyze the energy spectrum of gravitational waves only for axial modes, it would be possible to distinguish between an ultracompact star and a normal neutron star (or a Schwarzschild black hole).

  1. Cost effective combined axial fan and throttling valve control of ventilation rate

    E-Print Network [OSTI]

    Sengun, Mehmet Haluk

    Cost effective combined axial fan and throttling valve control of ventilation rate C.J. Taylor 1 P. In partic- ular, it develops a unique fan and throttling valve control system for a 22m3 test chamber, the throttling valve is employed to restrict airflow at the outlet, so generating a higher static pressure differ

  2. Three-dimensional model and simulation of vacuum arcs under axial magnetic fields

    SciTech Connect (OSTI)

    Wang Lijun; Jia Shenli; Zhou Xin; Wang Haijing; Shi Zongqian

    2012-01-15

    In this paper, a three-dimensional (3d) magneto-hydro-dynamic (MHD) model of axial magnetic field vacuum arcs (AMFVAs) is established. Based on this model, AMFVAs are simulated and analyzed. Three-dimensional spatial distributions of many important plasma parameters and electric characteristics in AMFVAs can be obtained, such as ion number density, ion temperature, electron temperature, plasma pressure, current densities along different directions (x, y, and z), ion velocities along different directions, electric fields strength along different directions, and so on. Simulation results show that there exist significant spiral-shaped rotational phenomena in the AMFVAs, this kind of rotational phenomenon also can be verified by the many related experiments (AMFVAs photographs, especially for stronger AMF strength). For current simulation results of AMFVAs, the maximal rotational velocity at anode side is about 1100 m/s. Radial electric field is increased from arc center to arc edge; axial electric field is decreased from cathode side to anode side. Radial electric field at arc edge can be larger than axial electric field. Azimuthal electric field in most regions is much smaller than radial and axial electric field, but it can reach about 1.19 kV/m. Radial magnetic field is the smallest one compared with other components, it reaches to maximum value at the position near to anode, it can influence arc characteristics.

  3. Late Quaternary constructional development of the Axial Volcanic Zone, eastern Snake River Plain, Idaho

    E-Print Network [OSTI]

    Wetmore, Paul H.

    Late Quaternary constructional development of the Axial Volcanic Zone, eastern Snake River Plain volcanic ridge that trends northeast across the middle of the eastern Snake River Plain, and acts Snake River Plain: the AVZ, the Big Lost Trough to the north, and the Arco-Big Southern Butte (ABSB

  4. Interpretation of Scalar and axial mesons in LHCb from an historical perspective

    E-Print Network [OSTI]

    F. E. Close; A. Kirk

    2015-03-24

    LHCb measurements of $B_{d,s} \\to J/\\psi + X$ are shown to be consistent with historical data on scalar and axial mesons below 2 GeV. This is in contrast to some recent interpretations of these data. Further tests of our hypotheses in other $B_{u,d,s} \\to J/\\psi + X$ decay modes are suggested.

  5. Influence of constraints on axial growth reduction of cylindrical Li-ion battery electrode particles

    E-Print Network [OSTI]

    Jeevanjyoti Chakraborty; Colin P. Please; Alain Goriely; S. Jonathan Chapman

    2014-11-24

    Volumetric expansion of silicon anode particles in a lithium-ion battery during charging may lead to the generation of undesirable internal stresses. For a cylindrical particle such growth may also lead to failure by buckling if the expansion is constrained in the axial direction due to other particles or supporting structures. To mitigate this problem, the possibility of reducing axial growth is investigated theoretically by studying simple modifications of the solid cylinder geometry. First, an annular cylinder is considered with lithiation either from the inside or from the outside. In both cases, the reduction of axial growth is not found to be significant. Next, explicit physical constraints are studied by addition of a non-growing elasto-plastic material: first, an outer annular constraint on a solid silicon cylinder, and second a rod-like inner constraint for an annular silicon cylinder. In both cases, it is found that axial growth can be reduced if the yield stress of the constraining material is significantly higher than that of silicon and/or the thickness of the constraint is relatively high. Phase diagrams are presented for both the outer and the inner constraint cases to identify desirable operating zones. Finally, to interpret the phase diagrams and isolate the key physical principles two different simplified models are presented and are shown to recover important qualitative trends of the numerical simulation results.

  6. Optical breakdown in transparent media with adjustable axial length and location

    E-Print Network [OSTI]

    Palanker, Daniel

    Optical breakdown in transparent media with adjustable axial length and location Ilya Toytman,1 of transparent materials. It might be useful for ophthalmic surgical applications including cataract surgery­430 (2006). 10. O. Brzobohatý, T. Cizmár, and P. Zemánek, "High quality quasi-Bessel beam generated by round

  7. Reducing axial offset and improving stability in PWRs by using uraniumethorium fuel

    E-Print Network [OSTI]

    Demazière, Christophe

    Reducing axial offset and improving stability in PWRs by using uraniumethorium fuel Cheuk Wah Lau a that a new type uraniumethorium (UeTh) based fuel assembly could be used to achieve a more homogenous radial that a core containing UeTh fuel assemblies also reduces the AO and improves the core stability

  8. Hydrogen bonding preference of equatorial versus axial hydroxyl groups in pyran and cyclohexane rings in organic crystals

    E-Print Network [OSTI]

    de Gispert, Adrià

    Paper Hydrogen bonding preference of equatorial versus axial hydroxyl groups in pyran of the hydrogen bonding counts in crystalline pyranose monosaccharides, we noticed that equatorial hydroxyls formed more hydrogen bonds, on average, than axial groups. A survey of the Cambridge Structural Database

  9. Experimental and Analytical Modeling of Concrete-Filled FRP Tubes Subjected to Combined Bending and Axial Loads

    E-Print Network [OSTI]

    structures were considered. Axial load - bending moment interaction curves are presented. The paper presents1 Experimental and Analytical Modeling of Concrete-Filled FRP Tubes Subjected to Combined Bending and Axial Loads Amir Fam 1 , Bart Flisak 2 and Sami Rizkalla 3 Abstract This paper presents test results

  10. Effects of Electromagnetic Fields on Fish and Invertebrates: Task 2.1.3: Effects on Aquatic Organisms - Fiscal Year 2011 Progress Report - Environmental Effects of Marine and Hydrokinetic Energy

    SciTech Connect (OSTI)

    Woodruff, Dana L.; Schultz, Irvin R.; Marshall, Kathryn E.; Ward, Jeffrey A.; Cullinan, Valerie I.

    2012-05-01

    This fiscal year (FY) 2011 progress report (Task 2.1.3 Effects on Aquatic Organisms, Subtask 2.3.1.1 Electromagnetic Fields) describes studies conducted by PNNL as part of the DOE Wind and Water Power Program to examine the potential effects of electromagnetic fields (EMF) from marine and hydrokinetic devices on aquatic organisms, including freshwater and marine fish and marine invertebrates. In this report, we provide a description of the methods and results of experiments conducted in FY 2010-FY 2011 to evaluate potential responses of selected aquatic organisms. Preliminary EMF laboratory experiments during FY 2010 and 2011 entailed exposures with representative fish and invertebrate species including juvenile coho salmon (Oncorhynchus kisutch), Atlantic halibut (Hippoglossus hippoglossus), California halibut (Paralicthys californicus), rainbow trout (Oncorhynchus mykiss), and Dungeness crab (Metacarcinus magister). These species were selected for their ecological, commercial, and/or recreational importance, as well as their potential to encounter an MHK device or transmission cable during part or all of their life cycle. Based on previous studies, acute effects such as mortality were not expected to occur from EMF exposures. Therefore, our measurement endpoints focused on behavioral responses (e.g., detection of EMF, interference with feeding behavior, avoidance or attraction to EMF), developmental changes (i.e., growth and survival from egg or larval stage to juvenile), and exposure markers indicative of physiological responses to stress. EMF intensities during the various tests ranged from 0.1 to 3 millitesla, representing a range of upper bounding conditions reported in the literature. Experiments to date have shown there is little evidence to indicate distinct or extreme behavioral responses in the presence of elevated EMF for the species tested. Several developmental and physiological responses were observed in the fish exposures, although most were not statistically significant. Additional species are currently planned for laboratory testing in the next fiscal year (e.g. an elasmobranch, American lobster) to provide a broader assessment of species important to stakeholders. The collective responses of all species will be assessed in terms of life stage, exposure scenarios, and biological relevance, to address current uncertainties related to effects of EMF on aquatic organisms.

  11. Preventing Buckling of Slender Cylindrical Structures by Internal Viscous Flows

    E-Print Network [OSTI]

    Max Linshits; Amir D. Gat

    2015-02-10

    Viscous flows within an elastic structure apply stress on the solid-liquid interface. The stress-field created by the viscous flow can be utilized to counter stress created by external forces and thus may be applied as a tool for delaying the onset of structural failure. To illustrate this concept we study viscous flow within an elastic cylinder under compressive axial force. We obtain a closed-form expression showing an approximately linear relation between the critical buckling load and the liquid inlet pressure. Our results are validated by numerical computations. We discuss future research directions of fluid-solid composite materials which create flow under external stress, yielding enhanced resistance to structural failure.

  12. Understanding order flow

    E-Print Network [OSTI]

    Evans, MDD; Lyons, Richard K.

    2006-01-01

    Understanding Order Flow October 2005 Martin D. D. Evans 1Rate Fundamentals and Order Flow, typescript, Georgetown2005), Customer Order Flow and Exchange Rate Movements: Is

  13. Linear and nonlinear stability analysis for two-dimensional ideal magnetohydrodynamics with incompressible flows

    SciTech Connect (OSTI)

    Khater, A.H.; Moawad, S.M.; Callebaut, D.K. [Department of Mathematics, Faculty of Science, Cairo University, Beni-Suef (Egypt); Departement Natuurkunde, Campus Drie Eiken, Universiteit Antwerpen - UA, B-2610 Antwerpen (Belgium)

    2005-01-01

    The equilibrium and Lyapunov stability properties for two-dimensional ideal magnetohydrodynamic (MHD) plasmas with incompressible and homogeneous (i.e., constant density) flows are investigated. In the unperturbed steady state, both the velocity and magnetic field are nonzero and have three components in a Cartesian coordinate system with translational symmetry (i.e., one ignorable spatial coordinate). It is proved that (a) the solutions of the ideal MHD steady state equations with incompressible and homogeneous flows in the plane are also valid for equilibria with the axial velocity component being a free flux function and the axial magnetic field component being a constant (b) the conditions of linearized Lyapunov stability for these MHD flows in the planar case (in which the fields have only two components) are also valid for symmetric equilibria that have a nonplanar velocity field component as well as a nonplanar magnetic field component. On using the method of convexity estimates, nonlinear stability conditions are established.

  14. \\(?\\) vector and axial-vector spectral functions in the extended linear sigma model

    E-Print Network [OSTI]

    A. Habersetzer; Francesco Giacosa

    2015-04-16

    The extended linear sigma model describes the vacuum phenomenology of scalar, pseudoscalar, vector and axial-vector mesons at energies \\(\\simeq 1\\text{ GeV}\\). We combine the chiral \\(U(2)_L\\times U(2)_R\\) symmetry of this model with a local \\(SU(2)_L\\times U(1)_Y\\) symmetry and obtain a gauge invariant effective description for electroweak interaction of hadrons in the vacuum. Vector and axial-vector spectral functions can be described well by two intermediate resonances \\(\\rho\\) and \\(a_1\\). They are implemented into this model as chiral partners and yield the predominant contributions to both spectral functions. However, the contributions that arise from the non-resonant decay channels of the weak charged \\(W\\) bosons are essential for reproducing the lineshapes of the spectral functions.

  15. A microscopic derivation of nuclear collective rotation-vibration model, axially symmetric case

    E-Print Network [OSTI]

    Parviz Gulshani

    2015-05-12

    We derive a microscopic version of the successful phenomenological hydrodynamic model of Bohr-Davydov-Faessler-Greiner for collective rotation-vibration motion of an axially symmetric deformed nucleus. The derivation is not limited to small oscillation amplitude. The nuclear Schrodinger equation is canonically transformed the to collective co-ordinates, which is then linearized using a constrained variational method. The associated constraints are imposed on the wavefunction rather than on the particle co-ordinates. The approach yields three self-consistent, time-reversal invariant, cranking-type Schrodinger equations for the rotation-vibration and intrinsic motions, and a self-consistency equation. For harmonic oscillator mean-field potentials, these equations are solved in closed forms and applied to the ground-state rotational bands in some axially-symmetric nuclei. The results are compared with the measured data.

  16. Experimental demonstration of a compact high efficient relativistic magnetron with directly axial radiation

    SciTech Connect (OSTI)

    Li Wei; Liu Yonggui; Shu Ting; Yang Hanwu; Fan Yuwei; Yuan Chengwei; Zhang Jun [College of Optoelectric Science and Engineering, National University of Defense Technology, Changsha, Hunan 410073 (China)

    2012-01-15

    A compact relativistic magnetron with axial microwave radiation is experimentally investigated. Under the modified magnetic field distribution, only connecting a special horn antenna in the axial direction, the relativistic magnetron can stably radiate high power and high efficiency microwaves. The total length of the device is {approx}0.3 m, and the volume is {approx}0.014m{sup 3}. In such working condition that the applied voltage is 539 kV and the magnetic field is {approx}0.38 T, the output microwave power is {approx}1.24 GW. Correspondingly, the total efficiency is about 34.1%. The radiating frequency is 2.35GHz, which is in agreement with the {pi} mode frequency of the theoretical expectation.

  17. Radiofrequency hydrogen ion source with permanent magnets providing axial magnetic field

    SciTech Connect (OSTI)

    Oikawa, Kohei, E-mail: oikawa@ecei.tohoku.ac.jp; Saito, Yuta; Komizunai, Shota; Takahashi, Kazunori; Ando, Akira [Department of Electrical Engineering, Tohoku University, Sendai 980-8579 (Japan)] [Department of Electrical Engineering, Tohoku University, Sendai 980-8579 (Japan)

    2014-02-15

    Uniform axial magnetic field of about 70 G is applied to a radiofrequency (rf) hydrogen ion source by arrays of permanent magnets. The plasma density and electron temperature downstream of the source and near the magnetic filter are compared with those in the previously described ion source, where the axial field has been applied by two solenoids. The source is operated at ?350 kHz and above 10 kW rf power with a field-effect-transistor-based invertor power supply in 1.5 Pa hydrogen. The results show that the plasma density of ?10{sup 19} m{sup ?3} near the source exit and ?10{sup 18} m{sup ?3} near the magnetic filter can be obtained, which are higher than those with the solenoids.

  18. Axial magnetic field generation by intense circularly polarized laser pulses in underdense plasmas

    SciTech Connect (OSTI)

    Naseri, N.; Rozmus, W. [Theoretical Physics Institute, University of Alberta, Edmonton, Alberta T6G 2J1 (Canada); Bychenkov, V. Yu. [Theoretical Physics Institute, University of Alberta, Edmonton, Alberta T6G 2J1 (Canada); P. N. Lebedev Physics Institute, Russian Academy of Sciences, Moscow 119991 (Russian Federation)

    2010-08-15

    Axial magnetic field generation by intense circularly polarized laser beams in underdense plasmas has been studied with three-dimensional particle-in-cell simulations and by means of theoretical analysis. Comparisons between analytical models and simulation results have identified an inverse Faraday effect as the main mechanism of the magnetic field generation in inhomogeneous plasmas. The source of azimuthal nonlinear currents and of the axial magnetic field depends on the transverse inhomogeneities of the electron density and laser intensity. The fields reach a maximum strength of several tens of megagauss for laser pulses undergoing relativistic self-focusing and channeling in moderately relativistic regime. Ultrarelativistic laser conditions inhibit magnetic field generation by directly reducing a source term and by generating fully evacuated plasma channels.

  19. Experimental buckling investigation of ring-stiffened cyclindrical shells under unsymmetrical axial loads

    SciTech Connect (OSTI)

    Baker, W.E.; Bennett, J.G.; Babcock, C.D.

    1983-01-01

    Six steel shells having nuclear containment-like features were fabricated and loaded to failure with an offset axial load. The shells of R/t = 500 buckled plastically. Four of the shells had reinforced circular cutouts. These penetrations were sized to cut no ring-stiffener, a single, two- or three-ring stiffeners. Reinforcing and framing around the penetrations were based upon the area-replacement rule of the applicable portion of the American Society for Mechanical Engineers (ASME) Boiler and Pressure Vessel Code and were of a design to simulate actual practice for nuclear steel containments. Prior to testing, imperfections were measured and strain gages were applied to determine information on load distribution at the ends of the cylinder and strain fields at areas likely to buckle. Buckling loads were determined for an axial load applied with an eccentricity of R/2 where R is the cylinder radius.

  20. The Flow of Power-Law Fluids in Axisymmetric Corrugated Tubes

    E-Print Network [OSTI]

    Sochi, Taha

    2010-01-01

    In this article we present an analytical method for deriving the relationship between the pressure drop and flow rate in laminar flow regimes, and apply it to the flow of power-law fluids through axially-symmetric corrugated tubes. The method, which is general with regards to fluid and tube shape within certain restrictions, can also be used as a foundation for numerical integration where analytical expressions are hard to obtain due to mathematical or practical complexities. Five converging-diverging geometries are used as examples to illustrate the application of this method.

  1. The Flow of Power-Law Fluids in Axisymmetric Corrugated Tubes

    E-Print Network [OSTI]

    Taha Sochi

    2010-06-13

    In this article we present an analytical method for deriving the relationship between the pressure drop and flow rate in laminar flow regimes, and apply it to the flow of power-law fluids through axially-symmetric corrugated tubes. The method, which is general with regards to fluid and tube shape within certain restrictions, can also be used as a foundation for numerical integration where analytical expressions are hard to obtain due to mathematical or practical complexities. Five converging-diverging geometries are used as examples to illustrate the application of this method.

  2. Charmless Hadronic B Decays into Vector, Axial Vector and Tensor Final States at BaBar

    SciTech Connect (OSTI)

    Gandini, Paolo; /Milan U. /INFN, Milan

    2012-04-06

    We present experimental measurements of branching fraction and longitudinal polarization fraction in charmless hadronic B decays into vector, axial vector and tensor final states with the final dataset of BABAR. Measurements of such kind of decays are a powerful tool both to test the Standard Model and search possible sources of new physics. In this document we present a short review of the last experimental results at BABAR concerning charmless quasi two-body decays in final states containing particles with spin 1 or spin 2 and different parities. This kind of decays has received considerable theoretical interest in the last few years and this particular attention has led to interesting experimental results at the current b-factories. In fact, the study of longitudinal polarization fraction f{sub L} in charmless B decays to vector vector (VV), vector axial-vector (VA) and axial-vector axial-vector (AA) mesons provides information on the underlying helicity structure of the decay mechanism. Naive helicity conservation arguments predict a dominant longitudinal polarization fraction f{sub L} {approx} 1 for both tree and penguin dominated decays and this pattern seems to be confirmed by tree-dominated B {yields} {rho}{rho} and B{sup +} {yields} {Omega}{rho}{sup +} decays. Other penguin dominated decays, instead, show a different behavior: the measured value of f{sub L} {approx} 0.5 in B {yields} {phi}K* decays is in contrast with naive Standard Model (SM) calculations. Several solutions have been proposed such as the introduction of non-factorizable terms and penguin-annihilation amplitudes, while other explanations invoke new physics. New modes have been investigated to shed more light on the problem.

  3. High-Efficiency Deflection of High-Energy Protons through Axial Channeling in a Bent Crystal

    E-Print Network [OSTI]

    Scandale, Walter; Baricordi, Stefano; Dalpiaz, Pietro; Fiorini, Massimiliano; Guidi, Vincenzo; Mazzolari, Andrea; Della Mea, Gianantonio; Milan, Riccardo; Ambrosi, Giovanni; Bertucci, Bruna; Burger, William J; Zuccon, Paolo; Cavoto, Gianluca; Luci, Claudio; Santacesaria, Roberta; Valente, Paolo; Vallazza, Erik; Afonin, Alexander G; Chesnokov, Yury A; Maisheev, Vladimir A; Yazynin, Igor A; Kovalenko, Alexander D; Taratin, Alexander M; Denisov, Alexander S; Gavrikov, Yury A; Ivanov, Yuri M; Lapina, Lyubov P; Malyarenko, Liudmila G; Skorobogatov, Vyacheslav V; Suvorov, Vsevolod M; Vavilov, Sergey A; Bolognini, Davide; Hasan, Said; Mozzanica, Aldo; Prest, Michela

    2008-01-01

    Beam deflection due to axial channeling in a silicon crystal bent along the [111] axis was observed with 400??GeV/c protons at the CERN Super Proton Synchrotron. The condition for doughnut scattering of protons by the atomic strings of the crystal was attained. Such a condition allowed one to observe a beam deflection of 50???rad with about 30% efficiency. The contribution of hyperchanneled states of protons to the observed beam deflection was less than 2% according to simulation results.

  4. Scattering of particles by neutron stars: Time-evolutions for axial perturbations

    E-Print Network [OSTI]

    V. Ferrari; K. D. Kokkotas

    2000-08-23

    The excitation of the axial quasi-normal modes of a relativistic star by scattered particles is studied by evolving the time dependent perturbation equations. This work is the first step towards the understanding of more complicated perturbative processes, like the capture or the scattering of particles by rotating stars. In addition, it may serve as a test for the results of the full nonlinear evolution of binary systems.

  5. Computation of the Field in an Axial Gap, Trapped-Flux Type Superconducting Electric Machine

    E-Print Network [OSTI]

    Shen, Zejun; Ainslie, Mark D.; Campbell, Archie M.; Cardwell, David A.

    2014-11-04

    Abstract—The Bulk Superconductivity Group at the University of Cambridge is currently investigating the use of high temper- ature superconductors in wire and bulk form to increase the electrical and magnetic loading of an axial gap, trapped flux... electric machines are an importantapplication of superconducting materials in both bulk and wire forms. Bulk high temperature superconductors, in partic- ular, are capable of trapping magnetic fields greater than 17 T below 30 K [1], [2], as well as up to 3...

  6. Fe XII STALKS AND THE ORIGIN OF THE AXIAL FIELD IN FILAMENT CHANNELS

    SciTech Connect (OSTI)

    Wang, Y.-M.; Sheeley, N. R. Jr.; Stenborg, G. E-mail: neil.sheeley@nrl.navy.mil

    2013-06-10

    Employing Fe XII images and line-of-sight magnetograms, we deduce the direction of the axial field in high-latitude filament channels from the orientation of the adjacent stalklike structures. Throughout the rising phase of the current solar cycle 24, filament channels poleward of latitude 30 Degree-Sign overwhelmingly obeyed the hemispheric chirality rule, being dextral (sinistral) in the northern (southern) hemisphere, corresponding to negative (positive) helicity. During the deep minimum of 2007-2009, the orientation of the Fe XII stalks was often difficult to determine, but no obvious violations of the rule were found. Although the hemispheric trend was still present during the maximum and early declining phase of cycle 23 (2000-2003), several high-latitude exceptions were identified at that time. From the observation that dextral (sinistral) filament channels form through the decay of active regions whose Fe XII features show a counterclockwise (clockwise) whorl, we conclude that the axial field direction is determined by the intrinsic helicity of the active regions. In contrast, generation of the axial field component by the photospheric differential rotation is difficult to reconcile with the observed chirality of polar crown and circular filament channels, and with the presence of filament channels along the equator. The main role of differential rotation in filament channel formation is to expedite the cancellation of flux and thus the removal of the transverse field component. We propose further that, rather than being ejected into the heliosphere, the axial field is eventually resubmerged by flux cancellation as the adjacent unipolar regions become increasingly mixed.

  7. Spectral Remittances of Chiral Sculptured Zirconia Thin Films in Non-axial propagation

    E-Print Network [OSTI]

    Babaei, Ferydon; 10.1080/09500340802130597

    2010-01-01

    The transmission and reflection spectra from a right-handed chiral sculptured zirconia thin film are calculated using the piecewise homogeneity approximation method and the Bruggeman homogenization formalism and considering that the dispersion of dielectric function happens in non-axial propagation state. First and second Bragg peaks were observed in cross-poloraized reflectances and it became clear that increasing the azimutal angle affects the spectra of linearly polarized state significantly. This is opposite to circularly polarized state.

  8. Design and market considerations for axial flux superconducting electric machine design

    E-Print Network [OSTI]

    Ainslie, Mark D; Shaw, Robert; Dawson, Lewis; Winfield, Andy; Steketee, Marina; Stockley, Simon

    2013-01-01

    In this paper, the authors investigate a number of design and market considerations for an axial flux superconducting electric machine design that uses high temperature superconductors. This work was carried out as part of the University of Cambridge's Centre for Entrepreneurial Learning ETECH Project programme, designed to accelerate entrepreneurship and diffusion of innovations based on early stage and potentially disruptive technologies from the University. The axial flux machine design is assumed to utilise high temperature superconductors in both wire (stator winding) and bulk (rotor field) forms, to operate over a temperature range of 65-77 K, and to have a power output in the range from 10s of kW up to 1 MW (typical for axial flux machines), with approximately 2-3 T as the peak trapped field in the bulk superconductors. The authors firstly investigate the applicability of this type of machine as a generator in small- and medium-sized wind turbines, including the current and forecasted market and pricin...

  9. Manipulating Magnetism: Ru-2(5+) Paddlewheels Devoid of Axial Interactions

    SciTech Connect (OSTI)

    Chiarella, Gina M [Texas A& M University; Cotton, F. A. [Texas A& M University; Murillo, Carlos A [Texas A& M University; Ventura, Karen [University of Texas at El Paso; Vilagran, Dino [University of Texas at El Paso; Wang, Xiaoping [ORNL

    2014-01-01

    Variable-temperature magnetic and structural data of two pairs of diruthenium isomers, one pair having an axial ligand and the formula Ru-2(DArF)(4)Cl (where DArF is the anion of a diarylformamidine isomer and Ar = p-anisyl or m-anisyl) and the other one being essentially identical but devoid of axial ligands and having the formula [Ru-2(DArF)(4)]BF4, show that the axial ligand has a significant effect on the electronic structure of the diruthenium unit. Variable temperature crystallographic and magnetic data as well as density functional theory calculations unequivocally demonstrate the occurrence of pi interactions between the p orbitals of the chlorine ligand and the pi* orbitals in the Ru-2(5+) units. The magnetic and structural data are consistent with the existence of combined ligand sigma/metal sigma and ligand p pi/metal-d pi interactions. Electron paramagnetic resonance data show unambiguously that the unpaired electrons are in metal-based molecular orbitals.

  10. The effect of plasma flow on line-tied magnetohydrodynamic modes

    SciTech Connect (OSTI)

    Arcudi, Francesco [Dipartimento di Energetica, Politecnico di Torino, 10129 Torino (Italy); Delzanno, Gian Luca; Finn, John M. [T-5, Applied Mathematics and Plasma Physics Group, Los Alamos National Laboratory, Los Alamos, New Mexico 87545 (United States)

    2010-06-15

    The linear stability of a linear pinch to kink modes with line-tying boundary conditions and equilibrium axial flow is studied. Numerical results in visco-resistive magnetohydrodynamics show that for long plasmas, in which the line-tying stabilization effect is weak, plasma flow is stabilizing. For shorter plasmas, near the length at which line-tying stabilizes the mode for zero flow, the flow can be destabilizing. A simple model using reduced ideal magnetohydrodynamics with a step-function current density and an even simpler one-dimensional sound wave model with equilibrium flow elucidate these effects. It is concluded that: (1) The stabilization in long plasmas is due to convective stabilization; (2) the destabilization for short plasmas can be explained using a picture involving the coupling of two stable waves, one propagating in the forward direction and one in the backward direction; and (3) strong magnetic shear suppresses the flow destabilization for short plasmas.

  11. Palladium-Catalyzed Enantioselective ?-Arylation and ?-Vinylation of Oxindoles Facilitated by an Axially Chiral P-Stereogenic Ligand

    E-Print Network [OSTI]

    Taylor, Alexander M.

    The enantioselective ?-arylation and ?-vinylation of oxindoles catalyzed by Pd and a biarylmonophosphine ligand with both axial and phosphorus-based chirogenicity is reported. The resultant quaternary carbon stereocenters ...

  12. Effect of Temporal Acquisition Parameters on the Image Quality of Ultrasound Axial Strain Time-constant Elastograms 

    E-Print Network [OSTI]

    Varghese, Joshua

    2011-08-02

    constant (TC) have been developed. The axial strain TC is a parameter that is related to the viscoelastic and poroelastic behavior of tissues. Estimation of this parameter can be done using curve fitting methods. However, the effect of temporal...

  13. Static and dynamic characteristics for a two-axial-groove bearing and a pressure-dam bearing 

    E-Print Network [OSTI]

    Al Jughaiman, Bader K.

    2009-06-02

    This thesis compares experimental static and dynamic force characteristics for a two-axial-groove bearing and a pressure-dam bearing without a relief track. The thesis also compares experimental results to predictions from a numerical analysis...

  14. Large-scale flow generation by inhomogeneous helicity

    E-Print Network [OSTI]

    Yokoi, Nobumitsu

    2015-01-01

    The effect of kinetic helicity (velocity--vorticity correlation) on turbulent momentum transport is investigated. The turbulent kinetic helicity (pseudoscalar) enters into the Reynolds stress (mirrorsymmetric tensor) expression in the form of a helicity gradient as the coupling coefficient for the mean vorticity and/or the angular velocity (axial vector), which suggests the possibility of mean-flow generation in the presence of inhomogeneous helicity. This inhomogeneous helicity effect, which was previously confirmed at the level of a turbulence- or closure-model simulation, is examined with the aid of direct numerical simulations of rotating turbulence with non-uniform helicity sustained by an external forcing. The numerical simulations show that the spatial distribution of the Reynolds stress is in agreement with the helicity-related term coupled with the angular velocity, and that a large-scale flow is generated in the direction of angular velocity. Such a large-scale flow is not induced in the case of hom...

  15. An investigation of two-phase gas-liquid slug flow

    SciTech Connect (OSTI)

    Mao, Z.

    1988-01-01

    Both experimental and numerical approaches were used in this study to explore the hydrodynamics of slug flow and its transition to the churn flow pattern. Extensive experimental data were taken using conductance wires, an electrochemical probe and a phase detection probe to simultaneously provide the axial void fraction distribution in the liquid slug, the axial profile of wall shear stress, the shape of the Taylor bubble, and the length and velocity of liquid slugs and Taylor bubbles. Data were collected for single Taylor bubbles rising in stagnant and flowing liquid as well as for continuous slug flow. A numerical method was developed for computing the flow field in the liquid slug and the falling film around a Taylor bubble. The field is first computed with a designated rise velocity and shape profile. Then the shape is adjusted to satisfy a constant pressure conditions at the free surface. It is shown that from an infinity of possible solutions the physically realistic Taylor bubble must have a rise velocity which creases a spherical nose in the vicinity of the vertex. The combination of experimental measurements and the numerical simulations reveal the details of slug flow and suggest that a circulating eddy exists at the top of a liquid slug. In contrast to conventional belief, churn flow is found to be better perceived as an extension of slug flow, instead of a distinct flow pattern. Numerical simulations for the flow around a single Taylor bubble give results in good agreement with the measured shape and the rise velocity of the bubble in both stagnant and flowing liquid for both turbulent and laminar flow. Similar computations for a train of bubbles show qualitative agreement with experiment.

  16. Three-dimensional rotating stall inception and effects of rotating tip clearance asymmetry in axial compressors

    E-Print Network [OSTI]

    Gordon, Kenneth A. (Kenneth Andrew), 1970-

    1999-01-01

    The effects of two types of flow nonuniformity on stall inception behavior were assessed with linearized stability analyses of two compressor flow models. Response to rotating tip clearance asymmetries induced by a whirling ...

  17. Steam-water two-phase flow in large diameter vertical piping at high pressures and temperatures

    SciTech Connect (OSTI)

    Hasanein, H.A.; Kawaji, Masahiro [Univ. of Toronto, Ontario (Canada); Chan, A.M.C. [Ontario Hydro Technologies, Toronto, Ontario (Canada); Yoshioka, Yuzuru [Japan Atomic Power Co., Tokyo (Japan)

    1996-08-01

    No information on steam/water two-phase flow behavior in large diameter pipes (10 inch or larger) at elevated pressures is available in the open literature. However, there are many applications, in the nuclear, chemical and petroleum industries among others where two-phase flows in large diameter pipes at elevated pressures and temperatures are encountered routinely or under accident scenarios. Experimental data on steam-water two-phase flow in a large diameter (20 inch, 50.08 cm I.D.) vertical pipe at elevated pressures and temperatures (2.8 MPa/230 C--6.4 MPa/280 C) have been obtained. Void fraction, two-phase mass flux, phase and velocity distributions as well as pressure drop along the test pipe have been measured using the Ontario Hydro Technologies (OHT) Pump Test Loop. The void fraction distributions were found to be axially symmetric and nearly flat over a wide range of two-phase flow conditions. The two-phase flow regime could be inferred from the dynamic void fluctuations data. For the 280 C tests, the flow was found to be relatively stable with bubbly flow at low average void fractions and churn turbulent or wispy-annular flow at higher void fractions. At 230 C, the flow became rather oscillatory and slugging was suspected at relatively low voids. It has also been found that the average void fractions in the test section can be determined reasonably accurately using the axial pressure drop data.

  18. Propeller Flow Meter 

    E-Print Network [OSTI]

    Enciso, Juan; Santistevan, Dean; Hla, Aung K.

    2007-10-01

    Propeller flow meters are commonly used to measure water flow rate. They can also be used to estimate irrigation water use. This publication explains how to select, install, read and maintain propeller flow meters....

  19. Bacteria in shear flow

    E-Print Network [OSTI]

    Marcos, Ph.D. Massachusetts Institute of Technology

    2011-01-01

    Bacteria are ubiquitous and play a critical role in many contexts. Their environment is nearly always dynamic due to the prevalence of fluid flow: creeping flow in soil, highly sheared flow in bodily conduits, and turbulent ...

  20. Dispersed flow film boiling

    E-Print Network [OSTI]

    Yoder, Graydon L.

    1980-01-01

    Dispersed flow consists of small liquid droplets entrained in a flowing vapor. This flow regime can occur in cryogenic equipment, in steam generators, and during nuclear reactor loss of coolant accidents. A theoretical ...

  1. Determing Degradation Of Fiberboard In The 9975 Shipping Package By Measuring Axial Gap

    SciTech Connect (OSTI)

    Hackney, E. R.; Dougherty, W. L.; Dunn, K. A.; Stefek, T. M

    2013-08-01

    Currently, thousands of model 9975 transportation packages are in use by the US Department of Energy (DOE); the design of which has been certified by DOE for shipment of Type B radioactive and fissile materials in accordance with Part 71, Title 10 Code of Federal Regulations (CFR), or 10 CFR 71, Packaging and Transportation of Radioactive Material. These transportation packages are also approved for the storage of DOE-STD-3013 containers at the Savannah River Site (SRS). As such, the 9975 has been continuously exposed to the service environment for a period of time greater than the approved transportation service life. In order to ensure the material integrity as specified in the safety basis, an extensive surveillance program is in place in K-Area Complex (KAC) to monitor the structural and thermal properties of the fiberboard of the 9975 shipping packages. The surveillance approach uses a combination of Non-Destructive Examination (NDE) field surveillance and Destructive Examination (DE) lab testing to validate the 9975 performance assumptions. The fiberboard in the 9975 is credited with thermal insulation, criticality control and resistance to crushing. During surveillance monitoring in KAC, an increased axial gap of the fiberboard was discovered on selected items packaged at Rocky Flats Environmental Technology Site (RFETS). Many of these packages were later found to contain excess moisture. Savannah River National Laboratory (SRNL) testing has resulted in a better understanding of the relationship between the fiberboard moisture level and compaction of the fiberboard under storage conditions and during transport. In laboratory testing, the higher moisture content has been shown to correspond to higher total compaction of fiberboard material and compaction rate. The fiberboard height is reduced by compression of the layers. This change is observed directly in the axial gap between the flange and the air shield. The axial gap measurement is made during the pre-use inspection or during the annual recertification process and is a screening measurement for changes in the fiberboard.

  2. Modular axial-flux permanent-magnet motor for ship propulsion drives

    SciTech Connect (OSTI)

    Caricchi, F.; Crescimbini, F.; Honorati, O.

    1999-09-01

    Original features such as compactness and lightness make slotless axial-flux permanent-magnet machines (AFPMs) eligible for application in large power motor drives devoted to the direct drive of ship propellers. This paper discusses characteristics of AFPMs designed for application in marine propulsion, and machine performances such as efficiency, weight and torque density are evaluated for a comparison with those of conventional synchronous machines. A newly-conceived modular arrangement of the machine stator winding is proposed and experimental results taken from a small-size machine prototype are finally shown.

  3. High-Efficiency Deflection of High-Energy Protons through Axial Channeling in a Bent Crystal

    SciTech Connect (OSTI)

    Scandale, Walter; Vomiero, Alberto; Baricordi, Stefano; Dalpiaz, Pietro; Fiorini, Massimiliano; Guidi, Vincenzo; Mazzolari, Andrea; Della Mea, Gianantonio; Milan, Riccardo; Ambrosi, Giovanni; Bertucci, Bruna; Burger, William J.; Zuccon, Paolo; Cavoto, Gianluca; Luci, Claudio; Santacesaria, Roberta; Valente, Paolo; Vallazza, Erik; Afonin, Alexander G.; Chesnokov, Yury A.

    2008-10-17

    Beam deflection due to axial channeling in a silicon crystal bent along the <111> axis was observed with 400 GeV/c protons at the CERN Super Proton Synchrotron. The condition for doughnut scattering of protons by the atomic strings of the crystal was attained. Such a condition allowed one to observe a beam deflection of 50 {mu}rad with about 30% efficiency. The contribution of hyperchanneled states of protons to the observed beam deflection was less than 2% according to simulation results.

  4. Axial range of conjugate adaptive optics in two-photon microscopy

    E-Print Network [OSTI]

    Paudel, Hari P; Mertz, Jerome; Bifano, Thomas

    2015-01-01

    We describe an adaptive optics technique for two-photon microscopy in which the deformable mirror used for aberration compensation is positioned in a plane conjugate to the plane of the aberration. We demonstrate in a proof-of-principle experiment that this technique yields a large field of view advantage in comparison to standard pupil-conjugate adaptive optics. Further, we show that the extended field of view in conjugate AO is maintained over a relatively large axial translation of the deformable mirror with respect to the conjugate plane. We conclude with a discussion of limitations and prospects for the conjugate AO technique in two-photon biological microscopy.

  5. Asymptotic axial symmetry of solutions of parabolic equations in bounded radial domains

    E-Print Network [OSTI]

    Saldana, Alberto

    2011-01-01

    We consider solutions of some nonlinear parabolic boundary value problems in radial bounded domains whose initial profile satisfy a reflection inequality with respect to a hyperplane containing the origin. We show that, under rather general assumptions, these solutions are asymptotically (in time) foliated Schwarz symmetric, i.e., all elements in the associated omega limit set are axially symmetric with respect to a common axis passing through the origin and nonincreasing in the polar angle from this axis. In this form, the result is new even for equilibria (i.e. solutions of the corresponding elliptic problem) and time periodic solutions.

  6. Spatiotemporal evolution of ponderomotive electron heating in axially inhomogeneous collisionless plasma

    SciTech Connect (OSTI)

    Mishra, S. K. [Institute for Plasma Research (IPR), Gandhinagar (India)] [Institute for Plasma Research (IPR), Gandhinagar (India); Sharma, A. [Institute of Physics, University of Pecs, Pecs 7624 (Hungary)] [Institute of Physics, University of Pecs, Pecs 7624 (Hungary)

    2013-07-15

    We investigate the spatiotemporal focusing dynamics of a Gaussian laser pulse in preformed collisionless plasma subjected to an axial nonuniformity in the plasma density. In order to follow up the pulse dynamics, a nonlinear Schrödinger wave equation characterizing the beam spot size in space and time frame has been derived and solved numerically to investigate the propagation characteristics as the pulse advances in the plasma. The effect of inhomogeneity on focusing length and ponderomotive electron heating have been analyzed and illustrated graphically. It is seen that ponderomotive heating is quite sensitive to the inhomogeneity parameters and the energy gain by electrons can be optimized by suitable choice of parameters.

  7. Halden In-Reactor Test to Exhibit PWR Axial Offset Anomaly

    SciTech Connect (OSTI)

    P.Bennett, B. Beverskog, R.Suther

    2004-12-01

    Many PWRs have encountered the axial offset anomaly (AOA) since the early 1990s, and these experiences have been reported widely. AOA is a phenomenon associated with localized boron hideout in corrosion product deposits (crud) on fuel surfaces. Several mitigation approaches have been developed or are underway to either delay the onset of AOA or avoid it entirely. This study describes the first phase of an experimental program designed to investigate whether the use of enriched boric acid (EBA) in the reactor coolant can mitigate AOA.

  8. Axial force imparted by a conical radiofrequency magneto-plasma thruster

    SciTech Connect (OSTI)

    Charles, C.; Takahashi, K.; Boswell, R. W. [Space Plasma, Power and Propulsion Laboratory, Research School of Physics and Engineering, Australian National University, ACT 0200 (Australia)

    2012-03-12

    Direct thrust measurements of a low pressure ({approx}0.133 Pa) conical radiofrequency (rf at 13.56 MHz) argon plasma source show a total axial force of about 5 mN for an effective rf power of 650 W and a maximum magnetic field of 0.018 T, of which a measured value of 2.5 mN is imparted by the magnetic nozzle. A simplified model of thrust including contributions from the electron pressure and from the magnetic field pressure is developed. The magnetic nozzle is modelled as a ''physical'' nozzle of increasing cross-sectional area.

  9. FLOW-THROUGH POROUS ELECTRODES

    E-Print Network [OSTI]

    Trainham, III, James Arthur

    2011-01-01

    configurations for flow redox battery applications: (i) theporous electrodes A flow-redox battery using flow-by poroustrue in battery applications, Flow..through porous

  10. Multiphase flow calculation software

    DOE Patents [OSTI]

    Fincke, James R. (Idaho Falls, ID)

    2003-04-15

    Multiphase flow calculation software and computer-readable media carrying computer executable instructions for calculating liquid and gas phase mass flow rates of high void fraction multiphase flows. The multiphase flow calculation software employs various given, or experimentally determined, parameters in conjunction with a plurality of pressure differentials of a multiphase flow, preferably supplied by a differential pressure flowmeter or the like, to determine liquid and gas phase mass flow rates of the high void fraction multiphase flows. Embodiments of the multiphase flow calculation software are suitable for use in a variety of applications, including real-time management and control of an object system.

  11. High energy density Z-pinch plasmas using flow stabilization

    SciTech Connect (OSTI)

    Shumlak, U. Golingo, R. P. Nelson, B. A. Bowers, C. A. Doty, S. A. Forbes, E. G. Hughes, M. C. Kim, B. Knecht, S. D. Lambert, K. K. Lowrie, W. Ross, M. P. Weed, J. R.

    2014-12-15

    The ZaP Flow Z-Pinch research project[1] at the University of Washington investigates the effect of sheared flows on MHD instabilities. Axially flowing Z-pinch plasmas are produced that are 100 cm long with a 1 cm radius. The plasma remains quiescent for many radial Alfvén times and axial flow times. The quiescent periods are characterized by low magnetic mode activity measured at several locations along the plasma column and by stationary visible plasma emission. Plasma evolution is modeled with high-resolution simulation codes – Mach2, WARPX, NIMROD, and HiFi. Plasma flow profiles are experimentally measured with a multi-chord ion Doppler spectrometer. A sheared flow profile is observed to be coincident with the quiescent period, and is consistent with classical plasma viscosity. Equilibrium is determined by diagnostic measurements: interferometry for density; spectroscopy for ion temperature, plasma flow, and density[2]; Thomson scattering for electron temperature; Zeeman splitting for internal magnetic field measurements[3]; and fast framing photography for global structure. Wall stabilization has been investigated computationally and experimentally by removing 70% of the surrounding conducting wall to demonstrate no change in stability behavior.[4] Experimental evidence suggests that the plasma lifetime is only limited by plasma supply and current waveform. The flow Z-pinch concept provides an approach to achieve high energy density plasmas,[5] which are large, easy to diagnose, and persist for extended durations. A new experiment, ZaP-HD, has been built to investigate this approach by separating the flow Z-pinch formation from the radial compression using a triaxial-electrode configuration. This innovation allows more detailed investigations of the sheared flow stabilizing effect, and it allows compression to much higher densities than previously achieved on ZaP by reducing the linear density and increasing the pinch current. Experimental results and scaling analyses will be presented. In addition to studying fundamental plasma science and high energy density physics, the ZaP and ZaP-HD experiments can be applied to laboratory astrophysics.

  12. Sandia Energy - Marine Hydrokinetics Technology: Reference Model...

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

    Offshore Wind High-Resolution Computational Algorithms for Simulating Offshore Wind Farms Innovative Offshore Vertical-Axis Wind Turbine Rotors Offshore Wind RD&D:...

  13. Marine and Hydrokinetic (MHK) Databases and Systems

    SciTech Connect (OSTI)

    2015-01-01

    The online information resources included in this fact sheet were developed with support from the U.S. Department of Energy, and are designed to provide the public access to information pertaining to MHK technologies, projects, and research.

  14. Sandia Energy - Marine Hydrokinetics Technology: Technology Developmen...

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

    and currenttidal power devices. Areas of focus will be on coatings, composites, and molding processes. System Reliability and Survivability Similar to other early stage...

  15. Marine and Hydrokinetic Technology (MHK) Instrumentation, Measurement...

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

    and Computer Modeling Workshop The workshop brought together over 60 experts in marine energy technologies to disseminate technical information to the marine energy...

  16. Acoustic Effects of Hydrokinetic Tidal Turbines

    SciTech Connect (OSTI)

    Polagye, Brian

    2011-11-01

    This presentation from the Water Peer Review highlights one of the program's marine and hyrokinetics environmental projects to determine the likely acoustic effects from a tidal energy device.

  17. Water Power Program: Marine and Hydrokinetic Technologies

    Office of Energy Efficiency and Renewable Energy (EERE)

    Pamphlet that describes the Office of EERE's Water Power Program in fiscal year 2009, including the fiscal year 2009 funding opportunities, the Small Business Innovation Research and Small Business Technology Transfer Programs, the U.S. hydrodynamic testing facilities, and the fiscal year 2008 Advanced Water Projects awards.

  18. Marine and Hydrokinetic Resources | Open Energy Information

    Open Energy Info (EERE)

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Home Page on Google Bookmark EERE: Alternative Fuels Data Center Home Page on QA:QAsource History View NewTexas:Montezuma,Information MHKMHK5TransportManitouChangeMarc

  19. Marine and Hydrokinetic | Open Energy Information

    Open Energy Info (EERE)

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Home Page on Google Bookmark EERE: Alternative Fuels Data Center Home Page on QA:QAsource History View NewTexas:Montezuma,Information MHKMHK5TransportManitouChangeMarcMarine andMarine and

  20. Marine & Hydrokinetic Technologies | Department of Energy

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

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Home Page on Google Bookmark EERE: Alternative Fuels Data Center Home Page on Delicious RankADVANCED MANUFACTURING OFFICESpecial Report Management ChallengesManufacturingMapandWater Power

  1. River Hydrokinetic Resource Atlas | Open Energy Information

    Open Energy Info (EERE)

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Home Page on Google Bookmark EERE: Alternative Fuels Data Center Home Page on QA:QA J-E-1 SECTION J APPENDIX ECoop Inc Jump to:Newberg,EnergyEast Jump to:Ridgway, Colorado:Ristma AG

  2. Marine and Hydrokinetic Resources | Open Energy Information

    Open Energy Info (EERE)

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  3. Siting Methodologies for Hydrokinetics | Department of Energy

    Energy Savers [EERE]

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  4. Experimental Design of Hydrokinetic Resource Characterization

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

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  5. Siting Methodologies for Hydrokinetics | Department of Energy

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

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  6. Sandia Energy - Marine Hydrokinetics Technology: Reference Model

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

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  7. Marine and Hydrokinetic Resource Assessment and Characterization |

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

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  8. Flow Distances on Open Flow Networks

    E-Print Network [OSTI]

    Guo, Liangzhu; Shi, Peiteng; Wang, Jun; Huang, Xiaohan; Zhang, Jiang

    2015-01-01

    Open flow network is a weighted directed graph with a source and a sink, depicting flux distributions on networks in the steady state of an open flow system. Energetic food webs, economic input-output networks, and international trade networks, are open flow network models of energy flows between species, money or value flows between industrial sectors, and goods flows between countries, respectively. Flow distances (first-passage or total) between any given two nodes $i$ and $j$ are defined as the average number of transition steps of a random walker along the network from $i$ to $j$ under some conditions. They apparently deviate from the conventional random walk distance on a closed directed graph because they consider the openness of the flow network. Flow distances are explicitly expressed by underlying Markov matrix of a flow system in this paper. With this novel theoretical conception, we can visualize open flow networks, calculating centrality of each node, and clustering nodes into groups. We apply fl...

  9. An Axial Vector Nature of a Neutrino with an Electroweak Mass

    E-Print Network [OSTI]

    Rasulkhozha S. Sharafiddinov

    2011-11-09

    A classification of elementary particles with respect to C-operation admits the existence of truly neutral types of fermions. Among them one can find both a Dirac and a Majorana neutrinos of an electroweak nature. Their mass includes the electric and weak parts, in the presence of which a neutrino has the anapole charge, charge radius and electric dipole moment. They constitute the paraneutrino of true neutrality, for example, at the neutrino interaction with a spinless nucleus of an axial-vector current. We derive the united equations which relate the structural components of mass to anapole, charge radius and electric dipole of each truly neutral neutrino at the level of flavour symmetry. Such a principle can explain the C-noninvariant nature of neutrinos and fields in the framework of constancy law of the size implied from the multiplication of a weak mass of the C-odd neutrino by its electric mass. From this point of view, all neutrinos of C-antisymmetricality regardless of the difference in masses of an axial-vector character, possess the same anapole with his radius as well as the identical electric dipole. Their analysis together with earlier measurements of an electric dipole moment of neutrino gives the right to accept not only the existence of truly neutral types of Dirac neutrinos and fields but also the availability of mass structure in them as the one of experimentally established facts.

  10. Broken axial symmetry as essential feature to predict radiative capture in heavy nuclei

    E-Print Network [OSTI]

    Grosse, Eckart; Massarczyk, Ralph

    2014-01-01

    Cross sections for neutron capture in the range of unresolved resonances are predicted for more than 140 spin-0 target nuclei with A > 50. Allowing the breaking of spherical and axial symmetry in nearly all these nuclei a combined parameterization for both, level density and photon strength is obtained which employs a surprisingly small number of parameters only. The strength functions used are based on a global fit to IVGDR shapes by the sum of three Lorentzians. They are based on theoretical predictions for the A-dependence of pole energies and spreading widths and add up to the TRK sum rule. For the small spins reached by capture resonance spacings are well described by a level density parameter close to the nuclear matter value; a significant collective enhancement is apparent due to the deviation from axial symmetry. Reliable predictions for compound nuclear reactions also outside the valley of stability (as important for nuclear astrophysics and for the transmutation of nuclear waste) are expected to re...

  11. Broken axial symmetry as essential feature to predict radiative capture in heavy nuclei

    E-Print Network [OSTI]

    Eckart Grosse; Arnd R. Junghans; Ralph Massarczyk

    2015-01-14

    Cross sections for neutron capture in the range of unresolved resonances are predicted for more than 140 spin-0 target nuclei with A > 50. Allowing the breaking of spherical and axial symmetry in nearly all these nuclei a combined parameterization for both, level density and photon strength is obtained which employs a surprisingly small number of parameters only. The strength functions used are based on a global fit to IVGDR shapes by the sum of three Lorentzians. They are based on theoretical predictions for the A-dependence of pole energies and spreading widths and add up to the TRK sum rule. For the small spins reached by capture resonance spacings are well described by a level density parameter close to the nuclear matter value; a significant collective enhancement is apparent due to the deviation from axial symmetry. Reliable predictions for compound nuclear reactions also outside the valley of stability (as important for nuclear astrophysics and for the transmutation of nuclear waste) are expected to result from the global parameterization presented.

  12. Fracture analysis of axially cracked pressure tube of pressurized heavy water reactor

    SciTech Connect (OSTI)

    Krishnan, S.; Bhasin, V.; Mahajan, S.C. [Bhabha Atomic Research Centre, Bombay (India)] [and others

    1997-04-01

    Three Dimensional (313) finite element elastic plastic fracture analysis was done for through wall axially cracked thin pressure tubes of 220 MWe Indian Pressurized Heavy Water Reactor. The analysis was done for Zr-2 and Zr-2.5Nb pressure tubes operating at 300{degrees}C and subjected to 9.5 Mpa internal pressure. Critical crack length was determined based on tearing instability concept. The analysis included the effect of crack face pressure due to the leaking fluid from tube. This effect was found to be significant for pressure tubes. The available formulae for calculating J (for axially cracked tubes) do not take into account the effect of crack face pressure. 3D finite element analysis also gives insight into variation of J across the thickness of pressure tube. It was observed that J is highest at the mid-surface of tube. The results have been presented in the form of across the thickness average J value and a peak factor on J. Peak factor on J is ratio of J at mid surface to average J value. Crack opening area for different cracked lengths was calculated from finite element results. The fracture assessment of pressure tubes was also done using Central Electricity Generating Board R-6 method. Ductile tearing was considered.

  13. A picoliter `fountain-pen' using co-axial dual pipettes Ofer Feinerman *, Elisha Moses

    E-Print Network [OSTI]

    Moses, Elisha

    , controlled drug infusion is presented. Two concentric pipettes can be manipulated separately and pressurized resolution of the infusion is highly controllable, and oscillatory flow can be generated. Three

  14. Portable wastewater flow meter

    DOE Patents [OSTI]

    Hunter, Robert M. (320 S. Wilson Ave., Bozeman, MT 59715)

    1999-02-02

    A portable wastewater flow meter particularly adapted for temporary use at a single location in measuring the rate of liquid flow in a circular entrance conduit of a sewer manhole both under free flow and submerged, open channel conditions and under fill pipe, surcharged conditions, comprising an apparatus having a cylindrical external surface and an inner surface that constricts the flow through the apparatus in such a manner that a relationship exists between (1) the difference between the static pressure head of liquid flowing through the entrance of the apparatus and the static pressure head of liquid flowing through the constriction, and (2) the rate of liquid flow through the apparatus.

  15. Portable wastewater flow meter

    DOE Patents [OSTI]

    Hunter, Robert M. (320 S. Wilson Ave., Bozeman, MT 59715)

    1990-01-01

    A portable wastewater flow meter particularly adapted for temporary use at a single location in measuring the rate of liquid flow in a circular entrance conduit of a sewer manhole both under free flow and submerged, open channel conditions and under full pipe, surcharged conditions, comprising an apparatus having a cylindrical external surface and an inner surface that constricts the flow through the apparatus in such a manner that a relationship exists between (1) the difference between the static pressure head of liquid flowing through the entrance of the apparatus and the static pressure head of liquid flowing through the constriction, and (2) the rate of liquid flow through the apparatus.

  16. Energy of eigen-modes in magnetohydrodynamic flows of ideal fluids

    E-Print Network [OSTI]

    I. V. Khalzov; A. I. Smolyakov; V. I. Ilgisonis

    2007-12-11

    Analytical expression for energy of eigen-modes in magnetohydrodynamic flows of ideal fluids is obtained. It is shown that the energy of unstable modes is zero, while the energy of stable oscillatory modes (waves) can assume both positive and negative values. Negative energy waves always correspond to non-symmetric eigen-modes -- modes that have a component of wave-vector along the equilibrium velocity. These results suggest that all non-symmetric instabilities in ideal MHD systems with flows are associated with coupling of positive and negative energy waves. As an example the energy of eigen-modes is calculated for incompressible conducting fluid rotating in axial magnetic field.

  17. Relaxation of axially confined 400 GeV/c protons to planar channeling in a bent crystal

    E-Print Network [OSTI]

    L. Bandiera; A. Mazzolari; E. Bagli; G. Germogli; V. Guidi; A. Sytov; I. V. Kirillin; N. F. Shul'ga; A. Berra; D. Lietti; M. Prest; D. De Salvador; E. Vallazza

    2015-11-10

    An investigation on the mechanism of relaxation of axially confined 400 GeV/c protons to planar channeling in a bent crystal was carried out at the extracted line H8 from CERN Super Proton Synchrotron. The experimental results were critically compared to computer simulations, showing a good agreement. We firmly individuated a necessary condition for the exploitation of axial confinement or its relaxation for particle beam manipulation in high-energy accelerators. We demonstrated that with a short bent crystal, aligned with one of its main axis to the beam direction, it is possible to realize either a total beam steerer or a beam splitter with adjustable intensity. In particular, in the latter case, a complete relaxation from axial confinement to planar channeling takes place, resulting in beam splitting into the two strongest skew planar channels.

  18. Relaxation of axially confined 400 GeV/c protons to planar channeling in a bent crystal

    E-Print Network [OSTI]

    Bandiera, L; Bagli, E; Germogli, G; Guidi, V; Sytov, A; Kirillin, I V; Shul'ga, N F; Berra, A; Lietti, D; Prest, M; De Salvador, D; Vallazza, E

    2015-01-01

    An investigation on the mechanism of relaxation of axially confined 400 GeV/c protons to planar channeling in a bent crystal was carried out at the extracted line H8 from CERN Super Proton Synchrotron. The experimental results were critically compared to computer simulations, showing a good agreement. We firmly individuated a necessary condition for the exploitation of axial confinement or its relaxation for particle beam manipulation in high-energy accelerators. We demonstrated that with a short bent crystal, aligned with one of its main axis to the beam direction, it is possible to realize either a total beam steerer or a beam splitter with adjustable intensity. In particular, in the latter case, a complete relaxation from axial confinement to planar channeling takes place, resulting in beam splitting into the two strongest skew planar channels.

  19. Microwave electron cyclotron electron resonance (ECR) ion source with a large, uniformly distributed, axially symmetric, ECR plasma volume

    DOE Patents [OSTI]

    Alton, Gerald D. (Kingston, TN)

    1996-01-01

    An electron cyclotron resonance (ECR) ion source includes a primary mirror coil disposed coaxially around a vacuum vessel in which a plasma is induced and introducing a solenoidal ECR-producing field throughout the length of the vacuum vessel. Radial plasma confinement is provided by a multi-cusp, multi-polar permanent magnet array disposed azimuthally around the vessel and within the primary mirror coil. Axial confinement is provided either by multi-cusp permanent magnets at the opposite axial ends of the vessel, or by secondary mirror coils disposed on opposite sides of the primary coil.

  20. Nucleon and Delta axial-vector couplings in 1/N{sub c}-Baryon Chiral Perturbation Theory

    SciTech Connect (OSTI)

    Goity, Jose Luis [JLAB; Calle Cordon, Alvaro [JLAB

    2013-08-01

    In this contribution, baryon axial-vector couplings are studied in the framework of the combined 1/N{sub c} and chiral expansions. This framework is implemented on the basis of the emergent spin-flavor symmetry in baryons at large N{sub c} and HBChPT, and linking both expansions ({xi}-expansion), where 1/N{sub c} is taken to be a quantity order p. The study is carried out including one-loop contributions, which corresponds to order xi to the third for baryon masses and order {xi} square for the axial couplings.

  1. Fluid mechanics experiments in oscillatory flow. Volume 1

    SciTech Connect (OSTI)

    Seume, J.; Friedman, G.; Simon, T.W.

    1992-03-01

    Results of a fluid mechanics measurement program is oscillating flow within a circular duct are present. The program began with a survey of transition behavior over a range of oscillation frequency and magnitude and continued with a detailed study at a single operating point. Such measurements were made in support of Stirling engine development. Values of three dimensionless parameters, Re{sub max}, Re{sub W}, and A{sub R}, embody the velocity amplitude, frequency of oscillation and mean fluid displacement of the cycle, respectively. Measurements were first made over a range of these parameters which included operating points of all Stirling engines. Next, a case was studied with values of these parameters that are representative of the heat exchanger tubes in the heater section of NASA`s Stirling cycle Space Power Research Engine (SPRE). Measurements were taken of the axial and radical components of ensemble-averaged velocity and rms-velocity fluctuation and the dominant Reynolds shear stress, at various radial positions for each of four axial stations. In each run, transition from laminar to turbulent flow, and in reverse, were identified and sufficient data was gathered to propose the transition mechanism. Models of laminar and turbulent boundary layers were used to process the data into wall coordinates and to evaluate skin friction coefficients. Such data aids in validating computational models and is useful in comparing oscillatory flow characteristics to those of fully-developed steady flow. Data were taken with a contoured entry to each end of the test section and with flush square inlets so that the effects of test section inlet geometry on transition and turbulence are documented. The following is presented in two-volumes. Volume I contains the text of the report including figures and supporting appendices. Volume II contains data reduction program listings and tabulated data (including its graphical presentation).

  2. Constraints on Axial Two-Body Currents from Solar Neutrino Data

    E-Print Network [OSTI]

    A. B. Balantekin; H. Yuksel

    2003-07-31

    We briefly review recent calculations of neutrino deuteron cross sections within the effective field theory and traditional potential model approaches. We summarize recent efforts to determine the counter term describing axial two-body currents, L_{1A}, in the effective field theory approach. We determine the counter term directly from the solar neutrino data and find several, slightly different, ranges of L_{1A} under different sets of assumptions. Our most conservative fit value with the largest uncertainty is L_{1A} = 4.5 +18/-12 fm^3. We show that the contribution of the uncertainty of L_{1A} to the analysis and interpretation of the solar neutrino data measured at the Sudbury Neutrino Observatory is significantly less than the uncertainty coming from the lack of having a better knowledge of \\theta_{13}.

  3. Failure probability of axially cracked steam generator tubes; A probabilistic fracture mechanics model

    SciTech Connect (OSTI)

    Mavko, B.; Cizelj, L. (Jozef Stefan Inst., Reactor Engineering Div., P.O. Box 100, 61111 Ljubljana, Slovenia (YU))

    1992-05-01

    In this paper a model for estimating the failure probability of axially cracked steam generator tubes is proposed. The model compares observed crack length distribution with critical crack length distribution by means of probabilistic fracture mechanics. The observed crack length is influenced by measured data, measurement reliability, sizing accuracy, and predicted crack growth rate. The critical crack length is defined by a deterministic mechanical model. All cracks are conservatively assumed to extend through the tube wall. The effect of the plugging limit is studied along with the number of cracked tubes to perform risk-based lifetime optimization of steam generators. A numerical example presented considers hypothetical accidental operating conditions during a feedwater line break.

  4. Magneto-hydrodynamics simulation study of deflagration mode in co-axial plasma accelerators

    SciTech Connect (OSTI)

    Sitaraman, Hariswaran; Raja, Laxminarayan L.

    2014-01-15

    Experimental studies by Poehlmann et al. [Phys. Plasmas 17(12), 123508 (2010)] on a coaxial electrode magnetohydrodynamic (MHD) plasma accelerator have revealed two modes of operation. A deflagration or stationary mode is observed for lower power settings, while higher input power leads to a detonation or snowplow mode. A numerical modeling study of a coaxial plasma accelerator using the non-ideal MHD equations is presented. The effect of plasma conductivity on the axial distribution of radial current is studied and found to agree well with experiments. Lower conductivities lead to the formation of a high current density, stationary region close to the inlet/breech, which is a characteristic of the deflagration mode, while a propagating current sheet like feature is observed at higher conductivities, similar to the detonation mode. Results confirm that plasma resistivity, which determines magnetic field diffusion effects, is fundamentally responsible for the two modes.

  5. Measurement and computation of heat transfer in high-pressure compressor drum geometries with axial throughflow

    SciTech Connect (OSTI)

    Long, C.A.; Morse, A.P.; Tucker, P.G.

    1997-01-01

    This paper makes comparisons between CFD computations and experimental measurements of heat transfer for the axial throughflow of cooling air in a high-pressure compressor spool rig and a plane cavity rig. The heat transfer measurements are produced using fluxmeters and by the conduction solution method from surface temperature measurements. Numerical predictions are made by solving the Navier-Stokes equations in a full three-dimensional, time-dependent form using the finite-volume method. Convergence is accelerated using a multigrid algorithm and turbulence modeled using a simple mixing length formulation. Notwithstanding systematic differences between the measurements and the computations, the level of agreement can be regarded as promising in view of the acknowledged uncertainties in the experimental data, the limitations of the turbulence model and, perhaps more importantly, the modest grid densities used for the computations.

  6. Hamiltonian dynamics of a symmetric top in external fields having axial symmetry. Levitating Orbitron

    E-Print Network [OSTI]

    Stanislav S. Zub; Sergiy I. Zub

    2015-02-13

    The symmetric top is a special case of the general top, and canonical Poisson structure on $T^*SE(3)$ is the common method of its description. This structure is invariant under the right action of $SO(3)$, but the Hamiltonian of the symmetric top is invariant only under the right action of subgroup $S^1$ that corresponds to the rotation around the symmetry axis of the symmetric top. So, its Poisson structure was obtained as the reduction $T^*SE(3)/S^1$. Next we propose the Hamiltonian that describes the wide class of the interaction models of symmetric top and axially-symmetric external field. The stability of the levitating Orbitron in relative equilibrium was proved.

  7. Measurements of the Ion Species of Cathodic Arc Plasma in an Axial Magnetic Field

    SciTech Connect (OSTI)

    Oks, Efim; Anders, Andre

    2010-10-19

    Metal and gas ion species and their charge state distributions were measured for pulsed copper cathodic arcs in argon background gas in the presence of an axial magnetic field. It was found that changing the cathode position relative to anode and ion extraction system as well as increasing the gas pressure did not much affect the arc burning voltage and the related power dissipation. However, the burning voltage and power dissipation greatly increased as the magnetic field strength was increased. The fraction of metal ions and the mean ion charge state were reduced as the discharge length was increased. The observations can be explained by the combination of charge exchange collisions and electron impact ionization. They confirm that previously published data on characteristic material-dependent charge state distributions (e.g., Anders and Yushkov, J. Appl. Phys., Vol. 91, pp. 4824-4832, 2002) are not universal but valid for high vacuum conditions and the specifics of the applied magnetic fields.

  8. Axial quasi-normal modes of Einstein-Gauss-Bonnet-dilaton neutron stars

    E-Print Network [OSTI]

    Blázquez-Salcedo, Jose Luis; Kunz, Jutta; Mojica, Sindy; Navarro-Lérida, Francisco

    2015-01-01

    We investigate axial quasi-normal modes of realistic neutron stars in Einstein-Gauss-Bonnet-dilaton gravity. We consider 8 realistic equations of state containing nuclear, hyperonic, and hybrid matter. We focus on the fundamental curvature mode and compare the results with those of pure Einstein theory. We observe that the frequency of the modes is increased by the presence of the Gauss-Bonnet-dilaton, while the impact on the damping time is typically smaller. Interestingly, we obtain that universal relations valid in pure Einstein theory still hold for Einstein-Gauss-Bonnet-dilaton gravity, and we propose a method to use these phenomenological relations to constrain the value of the Gauss-Bonnet coupling.

  9. Cyclic powder formation during pulsed injection of hexamethyldisiloxane in an axially asymmetric radiofrequency argon discharge

    SciTech Connect (OSTI)

    Despax, B.; Makasheva, K. [Universite de Toulouse, UPS, INPT, LAPLACE (Laboratoire Plasma et Conversion d'Energie), 118 route de Narbonne, F-31062 Toulouse 09 (France); CNRS, LAPLACE, F-31062 Toulouse cedex 09 (France); Caquineau, H. [Universite de Toulouse, UPS, INPT, LAPLACE (Laboratoire Plasma et Conversion d'Energie), 118 route de Narbonne, F-31062 Toulouse 09 (France)

    2012-11-01

    A new approach of periodic production of dusty plasma consisting of pulsed injection of hexamethyldisiloxane (HMDSO) in argon axially asymmetric radiofrequency (RF) discharge was investigated in this work. The range of plasma operating conditions in which this dusty plasma can exist was closely examined. The obtained results clearly show that a net periodicity in the formation/disappearance of dust particles in the plasma can be maintained on a very large scale of discharge duration. The significance of discharge axial asymmetry to the dust particles behaviour in the plasma is revealed by the development of an asymmetric in shape void shifted towards the powered RF electrode. The key role of the reactive gas and its pulsed injection on each stage of the oscillating process of formation/disappearance of dust particles is disclosed by optical and electrical measurements. It is shown that the period of dusty plasma formation/disappearance is inversely related to the HMDSO injection time. Moreover, the impact of time injection over short period (5 s) is examined. It indicates the conflicting role played by the HMDSO on the reduction of dusty plasma during the reactive gas injection and the reappearance of particles in the plasma during the time off. The electronegative behavior of the plasma in the presence of negatively charged particles seems to explain the energetic modifications in the discharge. A frequency analysis of the floating potential reveals all these cyclic processes. Particularly, in the 10-200 Hz frequency range, the presence and the evolution of dust particles in the plasma over one generation can be observed.

  10. Current scaling of axially radiated power in dynamic hohlraums and dynamic hohlraum load design for ZR.

    SciTech Connect (OSTI)

    Mock, Raymond Cecil; Nash, Thomas J.; Sanford, Thomas W. L.

    2007-03-01

    We present designs for dynamic hohlraum z-pinch loads on the 28 MA, 140 ns driver ZR. The scaling of axially radiated power with current in dynamic hohlraums is reviewed. With adequate stability on ZR this scaling indicates that 30 TW of axially radiated power should be possible. The performance of the dynamic hohlraum load on the 20 MA, 100 ns driver Z is extensively reviewed. The baseline z-pinch load on Z is a nested tungsten wire array imploding onto on-axis foam. Data from a variety of x-ray diagnostics fielded on Z are presented. These diagnostics include x-ray diodes, bolometers, fast x-ray imaging cameras, and crystal spectrometers. Analysis of these data indicates that the peak dynamic radiation temperature on Z is between 250 and 300 eV from a diameter less than 1 mm. Radiation from the dynamic hohlraum itself or from a radiatively driven pellet within the dynamic hohlraum has been used to probe a variety of matter associated with the dynamic hohlraum: the tungsten z-pinch itself, tungsten sliding across the end-on apertures, a titanium foil over the end aperture, and a silicon aerogel end cap. Data showing the existence of asymmetry in radiation emanating from the two ends of the dynamic hohlraum is presented, along with data showing load configurations that mitigate this asymmetry. 1D simulations of the dynamic hohlraum implosion are presented and compared to experimental data. The simulations provide insight into the dynamic hohlraum behavior but are not necessarily a reliable design tool because of the inherently 3D behavior of the imploding nested tungsten wire arrays.

  11. Space charge field in a FEL with axially symmetric electron beam

    SciTech Connect (OSTI)

    Goncharov, I.A.; Belyavskiy, E.D.

    1995-12-31

    Nonlinear two-dimensional theory of the space charge of an axially symmetric electron beam propagating in combined right-hand polarized wiggler and uniform axial guide fields in a presence of high-frequency electromagnetic wave is presented. The well-known TE{sub 01} mode in a cylindrical waveguide for the model of radiation fields and paraxial approximation for the wiggler field are used. Space charge field components are written in the Lagrange coordinates by the twice averaged Green`s functions of two equally charged infinitely thin discs. For that {open_quotes}compensating charges{close_quotes} method is applied in which an electron ring model is substituted by one with two different radii and signs discs. On this approach the initial Green`s functions peculiarities are eliminated and all calculations are considerably simplified. Coefficients of a twice averaged Green`s function expansion into a Fourier series are obtained by use of corresponding expansion coefficients of longitudinal Green`s functions of equal radii discs and identical rings known from the one-dimensional theory of super HF devices taking into account electron bunches periodicity. This approach permit the space charge field components for an arbitrary stratified stream to be expressed in a simple and strict enough form. The expressions obtained can be employed in a nonlinear two-dimensional FEL theory in order to investigate beam dynamical defocusing and electrons failing on the waveguide walls in the high gain regime. This is especially important for FEL operation in mm and submm.

  12. Mechanical annealing in the flow of supercooled metallic liquid

    SciTech Connect (OSTI)

    Zhang, Meng [State Key Lab of Materials Processing and Die and Mold Technology, School of Materials Science and Engineering, Huazhong University of Science and Technology, Wuhan 430074 (China); State Key Laboratory of Nonlinear Mechanics, Institute of Mechanics, Chinese Academy of Sciences, Beijing 100190 (China); Dai, Lan Hong [State Key Laboratory of Nonlinear Mechanics, Institute of Mechanics, Chinese Academy of Sciences, Beijing 100190 (China); Liu, Lin, E-mail: lliu2000@mail.hust.edu.cn [State Key Lab of Materials Processing and Die and Mold Technology, School of Materials Science and Engineering, Huazhong University of Science and Technology, Wuhan 430074 (China)

    2014-08-07

    Flow induced structural evolution in a supercooled metallic liquid Vit106a (Zr{sub 58.5}Cu{sub 15.6}Al{sub 10.3}Ni{sub 12.8}Nb{sub 2.8}, at.?%) was investigated via uni-axial compression combined with differential scanning calorimeter (DSC). Compression tests at strain rates covering the transition from Newtonian flow to non-Newtonian flow and at the same strain rate 2?×?10{sup ?1} s{sup ?1} to different strains were performed at the end of glass transition (T{sub g-end}?=?703?K). The relaxation enthalpies measured by DSC indicate that the samples underwent non-Newtonian flow contain more free volume than the thermally annealed sample (703?K, 4?min), while the samples underwent Newtonian flow contain less, namely, the free volume of supercooled metallic liquids increases in non-Newtonian flow, while decreases in Newtonian flow. The oscillated variation of the relaxation enthalpies of the samples deformed at the same strain rate 2?×?10{sup ?1} s{sup ?1} to different strains confirms that the decrease of free volume was caused by flow stress, i.e., “mechanical annealing.” Micro-hardness tests were also performed to show a similar structural evolution tendency. Based on the obtained results, the stress-temperature scaling in the glass transition of metallic glasses are supported experimentally, as stress plays a role similar to temperature in the creation and annihilation of free volume. In addition, a widening perspective angle on the glass transition of metallic glasses by exploring the 3-dimensional stress-temperature-enthalpy phase diagram is presented. The implications of the observed mechanical annealing effect on the amorphous structure and the work-hardening mechanism of metallic glasses are elucidated based on atomic level stress model.

  13. Flow Field Flow Fractionation Method Development for Applied Bioanalysis

    E-Print Network [OSTI]

    Schachermeyer, Samantha Lynn

    2013-01-01

    E. ; Caldwell, K. , Field-Flow Fractionation Handbook. JohnJ. P. , Sedimentation field-flow-fractionation: emergence ofby sedimentation field-flow fractionation. Am. Lab. (

  14. Construction of a new class of axially symmetric SU(N) monopole solutions by Neugebauer's dressing method

    SciTech Connect (OSTI)

    Pohle, H.

    1985-01-15

    In the framework of inverse scattering theory we apply Neugebauer's dressing method to the Bogomolny equation of spontaneously broken SU(N) gauge theory in the massless limit. We use this procedure to construct a new class of (N+3)-parameter solutions describing axially symmetric SU(N) monopoles.

  15. 3940 IEEE TRANSACTIONS ON MAGNETICS, Vol. 35, NO 5 SEPTEMBER 1999 Chartsfor Estimating the Axial Shielding Factors of

    E-Print Network [OSTI]

    Paperno, Eugene

    Shielding Factors of Open-EndedCylindrical Shields Eugene Paperno Dept. of Applied Science for Electronics and Materials, Kyushu University, 6-1 Kasuga-koen, Kasuga-shi,Fukuoka 816-8580.Japan Abstract-Axial shielding factors of single and double- shell open-ended cylindrical magnetic shields are calculated numerically

  16. Identification of spin wave modes in yttrium iron garnet strongly coupled to a co-axial cavity.

    E-Print Network [OSTI]

    Lambert, N. J.; Haigh, J. A.; Ferguson, A. J.

    2015-02-05

    AIP/123-QED Identification of spin wave modes in yttrium iron garnet strongly coupled to a co-axial cavity. N. J. Lambert,1 J. A. Haigh,2 and A. J. Ferguson1 1)Microelectronics Group, Cavendish Laboratory, University of Cambridge, Cambridge, CB3 0HE...

  17. Calculation of the heavy-hadron axial couplings g1, g2, and g3 using lattice QCD

    SciTech Connect (OSTI)

    Will Detmold, David Lin, Stefan Meinel

    2012-06-01

    In a recent paper [arXiv:1109.2480] we have reported on a lattice QCD calculation of the heavy-hadron axial couplings g{sub 1}, g{sub 2}, and g{sub 3}. These quantities are low-energy constants of heavy-hadron chiral perturbation theory (HH{chi}PT) and are related to the B*B{pi}, {Sigma}{sub b}*{Sigma}{sub b}{pi}, and {Sigma}{sub b}{sup (*)}{Lambda}{sub b}{pi} couplings. In the following, we discuss important details of the calculation and give further results. To determine the axial couplings, we explicitly match the matrix elements of the axial current in QCD with the corresponding matrix elements in HH{chi}PT. We construct the ratios of correlation functions used to calculate the matrix elements in lattice QCD, and study the contributions from excited states. We present the complete numerical results and discuss the data analysis in depth. In particular, we demonstrate the convergence of SU(4|2) HH{chi}PT for the axial current matrix elements at pion masses up to about 400 MeV and show the impact of the nonanalytic loop contributions. Finally, we present additional predictions for strong and radiative decay widths of charm and bottom baryons.

  18. Energy release from hadron-quark phase transition in neutron stars and the axial w mode of gravitational waves 

    E-Print Network [OSTI]

    Lin, Weikang; Li, Bao-An; Xu, Jun; Ko, Che Ming; Wen, De Hua.

    2011-01-01

    the energy release from a neutron star owing to the hadron-quark phase transition. Moreover, the frequency and damping time of the first axial w mode of gravitational waves are studied for both hyperonic and hybrid stars. We find that the energy release...

  19. Ultrasonic flow metering system

    DOE Patents [OSTI]

    Gomm, Tyler J. (Meridian, ID); Kraft, Nancy C. (Idaho Falls, ID); Mauseth, Jason A. (Pocatello, ID); Phelps, Larry D. (Pocatello, ID); Taylor, Steven C. (Idaho Falls, ID)

    2002-01-01

    A system for determining the density, flow velocity, and mass flow of a fluid comprising at least one sing-around circuit that determines the velocity of a signal in the fluid and that is correlatable to a database for the fluid. A system for determining flow velocity uses two of the inventive circuits with directional transmitters and receivers, one of which is set at an angle to the direction of flow that is different from the others.

  20. Effect of asymmetric axial strain on the behavior of the juncture vortex system 

    E-Print Network [OSTI]

    Trosper, Jeffrey Randall

    1994-01-01

    plexiglass plate. For various airfoil angles of attack, the flow in the juncture was visualized with hydrogen bubbles and with fluorescein dye and the data was recorded on videotape and analyzed quantitatively using a video-based motion analysis system...

  1. Elbow mass flow meter

    DOE Patents [OSTI]

    McFarland, Andrew R. (College Station, TX); Rodgers, John C. (Santa Fe, NM); Ortiz, Carlos A. (Bryan, TX); Nelson, David C. (Santa Fe, NM)

    1994-01-01

    Elbow mass flow meter. The present invention includes a combination of an elbow pressure drop generator and a shunt-type mass flow sensor for providing an output which gives the mass flow rate of a gas that is nearly independent of the density of the gas. For air, the output is also approximately independent of humidity.

  2. FLOW-THROUGH POROUS ELECTRODES

    E-Print Network [OSTI]

    Trainham, III, James Arthur

    2011-01-01

    Wilhelm. HBoundary conditions of a flow reactor. 1i Chemicala Packed-Bed Electrochemical Flow Reactor." Journal ofRichard, and Brian Gracon. "Flow-Through Porous Electrodes."

  3. Redox Flow Batteries, a Review

    E-Print Network [OSTI]

    Weber, Adam Z.

    2013-01-01

    Ltd." . Http://Plurionsystems.Com/Tech_Flow_Advantages.Html.plurionsystems.com/tech_flow_advantages.html [71] P. Leung,High Energy Density Redox Flow Device," ed: WO Patent

  4. An experimental and analytical study of annular two phase flow friction pressure drop in a reduced acceleration field 

    E-Print Network [OSTI]

    Wheeler, Montgomery

    1992-01-01

    instrumentation effects schematic for positive tube axial acceleration. . . . . . . . 28 2. 7 Initialization parabolas of December 17, 1991 2. 8 Initialization parabolas of August 20, 1991 2. 9 Initialization parabola of January 23, 1992 3. 1 Annular flow... uncorrected data and calibration, offset, and hydrostatic head corrected pressure drop data. . 4. 2 Reduced acceleration friction pressure drops for separate adiabatic test sections 4. 3 Comparison of friction pressure drops in reduced acceleration and I-g...

  5. Lateral flow strip assay

    DOE Patents [OSTI]

    Miles, Robin R. (Danville, CA); Benett, William J. (Livermore, CA); Coleman, Matthew A. (Oakland, CA); Pearson, Francesca S. (Livermore, CA); Nasarabadi, Shanavaz L. (Livermore, CA)

    2011-03-08

    A lateral flow strip assay apparatus comprising a housing; a lateral flow strip in the housing, the lateral flow strip having a receiving portion; a sample collection unit; and a reagent reservoir. Saliva and/or buccal cells are collected from an individual using the sample collection unit. The sample collection unit is immersed in the reagent reservoir. The tip of the lateral flow strip is immersed in the reservoir and the reagent/sample mixture wicks up into the lateral flow strip to perform the assay.

  6. Low flow fume hood

    DOE Patents [OSTI]

    Bell, Geoffrey C. (Pleasant Hill, CA); Feustel, Helmut E. (Albany, CA); Dickerhoff, Darryl J. (Berkeley, CA)

    2002-01-01

    A fume hood is provided having an adequate level of safety while reducing the amount of air exhausted from the hood. A displacement flow fume hood works on the principal of a displacement flow which displaces the volume currently present in the hood using a push-pull system. The displacement flow includes a plurality of air supplies which provide fresh air, preferably having laminar flow, to the fume hood. The displacement flow fume hood also includes an air exhaust which pulls air from the work chamber in a minimally turbulent manner. As the displacement flow produces a substantially consistent and minimally turbulent flow in the hood, inconsistent flow patterns associated with contaminant escape from the hood are minimized. The displacement flow fume hood largely reduces the need to exhaust large amounts of air from the hood. It has been shown that exhaust air flow reductions of up to 70% are possible without a decrease in the hood's containment performance. The fume hood also includes a number of structural adaptations which facilitate consistent and minimally turbulent flow within a fume hood.

  7. Measurement Of The Fluid Flow Load On A Globe Valve Stem Under Various Cavitation Conditions

    E-Print Network [OSTI]

    Ferrari, Jerome

    2009-01-01

    The evaluation of fluid forces on the stem is important for wear prediction of valve and actuator guidance parts. While estimating the axial load is straight forward, estimating and/or measuring the side load is more difficult, especially for globe valves. Therefore, measurements are carried out on an ad hoc, scale 1, model of a 2" globe valve. The body is replicated in Plexiglas to enable flow visualization and the original stem is heavily instrumented to allow force measurements in every direction. The flow loop facility used for this experiment is designed to allow fine-tuning of the cavitation intensity. The experiment is run for a set of cavitation conditions, flow rates and disc positions. The results show that the transverse force (perpendicular to the stem) can reach the order of the axial force; thus it should not be ignored. We also observed that it depends very weakly on the cavitation levels. Videos made with a high-speed camera allow an interesting understanding of the fluid flow and the cavitati...

  8. PWR FLECHT SEASET 21-rod bundle flow blockage task. Task plan report. FLECHT SEASET Program report No. 5

    SciTech Connect (OSTI)

    Hochreiter, L.E.; Basel, R.A.; Dennis, R.J.; Lee, N.; Massie, H.W. Jr.; Loftus, M.J.; Rosal, E.R.; Valkovic, M.M.

    1980-10-01

    This report presents a descriptive plan of tests for the 21-Rod Bundle Flow Blockage Task of the Full-Length Emergency Cooling Heat Transfer Separate Effects and Systems Effects Test Program (FLECHT SEASET). This task will consist of forced and gravity reflooding tests utilizing electrical heater rods to simulate PWR nuclear core fuel rod arrays. All tests will be performed with a cosine axial power profile. These tests are planned to be used to determine effects of various flow blockage configurations (shapes and distributions) on reflooding behavior, to aid in development/assessment of computational models in predicting reflooding behavior of flow blockage configurations, and to screen flow blockage configurations for future 161-rod flow blockage bundle tests.

  9. Experimental and numerical study of mixed convection with flow reversal in coaxial double-duct heat exchangers

    SciTech Connect (OSTI)

    Mare, Thierry; Voicu, Ionut; Miriel, Jacques [Laboratoire de Genie Civil et de Genie Mecanique (LGCGM), INSA de Rennes, IUT Saint Malo, 35043 Rennes (France); Galanis, Nicolas [Faculte de genie, Universite de Sherbrooke, Sherbrooke, QC (Canada); Sow, Ousmane [Laboratoire d'Energie Appliquee, Ecole superieure Polytechnique, Dakar (Senegal)

    2008-04-15

    Velocity vectors in a vertical coaxial double-duct heat exchanger for parallel ascending flow of water under conditions of laminar mixed convection have been determined experimentally using the particle image velocimetry technique. The measured velocity distributions for large annular flow rates, resulting in an essentially isothermal environment for the stream in the inner tube, are in very good agreement with corresponding numerical predictions. For flow rates of the same order of magnitude in the inner tube and the annulus, and corresponding temperature differences of about 20 C, experimental observations show that flow reversal occurs simultaneously in both streams over large axial distances for both heating and cooling of the flow in the inner tube. (author)

  10. Improved blade profile loss and deviation angle models for advanced transonic compressor bladings. Part 2: A model for supersonic flow

    SciTech Connect (OSTI)

    Koenig, W.M.; Hennecke, D.K.; Fottner, L.

    1996-01-01

    New blading concepts as used in modern transonic axial-flow compressors require improved loss and deviation angle correlations. The new model presented in this paper incorporates several elements and treats blade-row flows having subsonic and supersonic inlet conditions separately. The second part of the present report focuses on the extension of a well-known correlation for cascade losses at supersonic inlet flows. It was originally established for DCA bladings and is now modified to reflect the flow situation in blade rows having low-cambered, arbitrarily designed blades including precompression blades. Finally, the steady loss increase from subsonic to supersonic inlet-flow velocities demonstrates the matched performance of the different correlations of the new model.

  11. Deformation Behavior and TExture Evolution of Steel Alloys under Axial-Torsional Loading

    SciTech Connect (OSTI)

    Siriruk, A.; Kant, M.; Penumadu, D.; Garlea, E.; Vogel, S.

    2011-06-01

    Using hollow cylinder samples with suitable geometry obtained from round bar stock, the deformation behavior of bcc Fe based 12L14 steel alloy is evaluated under multi-axial conditions. A stacked strain gage rosette and extensometer mounted on the cylindrical surface at the mid height of the specimen provided strain tensor as a function of applied stress for pure tensile and torsion tests prior to yielding. This study examines elastic and yield behavior and effects of these with respect to texture evolution. Hollow cylinder specimen geometry (tubes) with small wall thickness and relatively (to its thickness) large inner diameter is used. The variation of observed yield surface in deviatoric plane and the effect on mode of deformation (tension versus torsion versus its combination) on stress-strain behavior is discussed. Bulk texture was studied using neutron time-of-flight diffractometer at High-Pressure-Preferred Orientation (HIPPO) - Los Alamos Neutron Science Center (LANSCE) instrument and the evolution of texture and related anisotropy for pure tension versus torsion are also included.

  12. Strain and stability of ultrathin Ge layers in Si/Ge/Si axial heterojunction nanowires

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

    Ross, Frances M.; Stach, Eric A.; Wen, Cheng -Yen; Reuter, Mark C.; Su, Dong

    2015-02-05

    The abrupt heterointerfaces in the Si/Ge materials system presents useful possibilities for electronic device engineering because the band structure can be affected by strain induced by the lattice mismatch. In planar layers, heterointerfaces with abrupt composition changes are difficult to realize without introducing misfit dislocations. However, in catalytically grown nanowires, abrupt heterointerfaces can be fabricated by appropriate choice of the catalyst. Here we grow nanowires containing Si/Ge and Si/Ge/Si structures respectively with sub-1nm thick Ge "quantum wells" and we measure the interfacial strain fields using geometric phase analysis. Narrow Ge layers show radial strains of several percent, with a correspondingmore »dilation in the axial direction. Si/Ge interfaces show lattice rotation and curvature of the lattice planes. We conclude that high strains can be achieved, compared to what is possible in planar layers. In addition, we study the stability of these heterostructures under heating and electron beam irradiation. The strain and composition gradients are supposed to the cause of the instability for interdiffusion.« less

  13. The twofold emergence of the $a_1$ axial vector meson in high energy hadronic production

    E-Print Network [OSTI]

    Jean-Louis Basdevant; Edmond L. Berger

    2015-01-19

    The high statistics COMPASS results on diffractive dissociation $\\pi N \\rightarrow \\pi \\pi \\pi N$ suggest that the isospin $I=1$ spin-parity $J^{PC}= 1^{++}$ $a_1(1260)$ resonance could be split into two states: $a_1(1260)$ decaying into an S-wave $\\rho\\pi$ system, and $a_1^\\prime(1420)$ decaying into a P-wave $f_0(980)\\pi$ system. We analyse the reaction by incorporating our previous treatment of resonant re-scattering corrections in the Drell-Deck forward production process. Our results show that the COMPASS results are fully consistent with the existence of a single axial-vector $a_1$ resonance. The characteristic structure of the production process, which differs in the two orbital angular momentum states, plays a crucial role in this determination. Provided the theoretical analysis of the reaction is done in a consistent manner, this single resonance produces two peaks at different locations in the two channels, with a rapid increase of the phase difference between their amplitudes arising mainly from the structure of the production process itself, and not from a dynamical resonance effect. In addition, this analysis clarifies questions related to the mass, width, and decay rates of the $a_1$ resonance.

  14. Pipe Flow System Holly Guest

    E-Print Network [OSTI]

    Clement, Prabhakar

    Pipe Flow System Design Holly Guest #12;Problem · An engineer is asked to compute the flow rate · Flow type: Turbulent or Laminar flow · Flow rate · Frictional head loss · Optimal diameters if a pump · = - ( . + . ) · f = friction factor · = relative roughness = · = Reynolds Number = · Laminar flow: 2000

  15. Flow patterns in vertical two-phase flow

    SciTech Connect (OSTI)

    McQuillan, K.W.; Whalley, P.B.

    1985-03-01

    This paper is concerned with the flow patterns which occur in upwards gas-liquid two-phase flow in vertical tubes. The basic flow patterns are described and the use of flow patter maps is discussed. The transition between plug flow and churn flow is modelled under the assumption that flooding of the falling liquid film limits the stability of plug flow. The resulting equation is combined with other flow pattern transition equations to produce theoretical flow pattern maps, which are then tested against experimental flow pattern data. Encouraging agreement is obtained.

  16. PWR FLECHT SEASET 163-Rod Bundle Flow Blockage Task data report. NRC/EPRI/Westinghouse report No. 13, August-October 1982

    SciTech Connect (OSTI)

    Loftus, M J; Hochreiter, L E; McGuire, M F; Valkovic, M M

    1983-10-01

    This report presents data from the 163-Rod Bundle Blow Blockage Task of the Full-Length Emergency Cooling Heat Transfer Systems Effects and Separate Effects Test Program (FLECHT SEASET). The task consisted of forced and gravity reflooding tests utilizing electrical heater rods with a cosine axial power profile to simulate PWR nuclear core fuel rod arrays. These tests were designed to determine effects of flow blockage and flow bypass on reflooding behavior and to aid in the assessment of computational models in predicting the reflooding behavior of flow blockage in rod bundle arrays.

  17. Forced Granular Orifice Flow

    E-Print Network [OSTI]

    Zheng Peng; Hepeng Zheng; Yimin Jiang

    2009-09-06

    The flow of granular material through an orifice is studied experimentally as a function of force $F$ pushing the flow. It is found that the flow rate increases linearly with $F$ -- a new, unexpected result that is in contrast to the usual view that $F$, completely screened by an arch formed around the orifice, has no way of altering the rate. Employing energy balance, we show that this behavior results mainly from dissipation in the granular material.

  18. Turbulent flow in graphene

    E-Print Network [OSTI]

    Kumar S. Gupta; Siddhartha Sen

    2010-06-05

    We demonstrate the possibility of a turbulent flow of electrons in graphene in the hydrodynamic region, by calculating the corresponding turbulent probability density function. This is used to calculate the contribution of the turbulent flow to the conductivity within a quantum Boltzmann approach. The dependence of the conductivity on the system parameters arising from the turbulent flow is very different from that due to scattering.

  19. Solids mass flow determination

    DOE Patents [OSTI]

    Macko, Joseph E. (Hempfield Township, Westmoreland County, PA)

    1981-01-01

    Method and apparatus for determining the mass flow rate of solids mixed with a transport fluid to form a flowing mixture. A temperature differential is established between the solids and fluid. The temperature of the transport fluid prior to mixing, the temperature of the solids prior to mixing, and the equilibrium temperature of the mixture are monitored and correlated in a heat balance with the heat capacities of the solids and fluid to determine the solids mass flow rate.

  20. Technique for high axial shielding factor performance of large-scale, thin, open-ended, cylindrical Metglas magnetic shields

    E-Print Network [OSTI]

    Malkowski, S; Hona, B; Mattie, C; Woods, D; Yan, H; Plaster, B; 10.1063/1.3605665

    2011-01-01

    Metglas 2705M is a low-cost commercially-available, high-permeability Cobalt-based magnetic alloy, provided as a 5.08-cm wide and 20.3-$\\mu$m thick ribbon foil. We present an optimized construction technique for single-shell, large-scale (human-size), thin, open-ended cylindrical Metglas magnetic shields. The measured DC axial and transverse magnetic shielding factors of our 0.61-m diameter and 1.83-m long shields in the Earth's magnetic field were 267 and 1500, for material thicknesses of only 122 $\\mu$m (i.e., 6 foil layers). The axial shielding performance of our single-shell Metglas magnetic shields, obtained without the use of magnetic shaking techniques, is comparable to the performance of significantly thicker, multiple-shell, open-ended Metglas magnetic shields in comparable-magnitude, low-frequency applied external fields reported previously in the literature.

  1. Introducing thermally stable inter-tube defects to assist off-axial phonon transport in carbon nanotube films

    SciTech Connect (OSTI)

    Wang, Jing [Department of Materials Science and Engineering, Texas A and M University, College Station, Texas 77843 (United States); Chen, Di; Wallace, Joseph; Gigax, Jonathan; Wang, Xuemei [Department of Nuclear Engineering, Texas A and M University, College Station, Texas, 77843 (United States); Shao, Lin, E-mail: lshao@tamu.edu [Department of Materials Science and Engineering, Texas A and M University, College Station, Texas 77843 (United States); Department of Nuclear Engineering, Texas A and M University, College Station, Texas, 77843 (United States)

    2014-05-12

    Through integrated molecular dynamics (MD) simulations and experimental studies, we demonstrated the feasibility of an ion-irradiation-and-annealing based phonon engineering technique to enhance thermal conductivity of carbon nanotube (CNT) films. Upon ion irradiation of CNT films, both inter-tube defects and intra-tube defects are introduced. Our MD simulations show that inter-tube defects created between neighboring tubes are much more stable than intra-tube defects created on tube graphitic planes. Upon thermal annealing, intra-tube defects are preferentially removed but inter-tube defects stay. Consequently, axial phonon transport increases due to reduced phonon scattering and off-axial phonon transport is sustained due to the high stability of inter-tube defects, leading to a conductivity enhancement upon annealing. The modeling predictions agree with experimental observations that thermal conductivities of CNT films were enhanced after 2?MeV hydrogen ion irradiations and conductivities were further enhanced upon post irradiation annealing.

  2. The effect of the electron-beam parameter spread on microwave generation in a three-cavity axial vircator

    E-Print Network [OSTI]

    E. A. Gurnevich; P. V. Molchanov

    2014-07-31

    The behavior of the generation efficiency and radiation spectrum of a three-cavity axial vircator versus the radius of the injected electron beam, its impedance and energy homogeneity is studied. This paper establishes that for each geometry of a three-cavity resonator, there exist the optimal (maximizing the generation efficiency) values of these parameters and determines the range within which they may vary without losing the efficiency of generation.

  3. Inclusive tau lepton hadronic decay in vector and axial-vector channels within dispersive approach to QCD

    E-Print Network [OSTI]

    Nesterenko, A V

    2015-01-01

    The dispersive approach to QCD, which properly embodies the intrinsically nonperturbative constraints originating in the kinematic restrictions on relevant physical processes and extends the applicability range of perturbation theory towards the infrared domain, is briefly overviewed. The study of OPAL (update 2012) and ALEPH (update 2014) experimental data on inclusive tau lepton hadronic decay in vector and axial-vector channels within dispersive approach is presented.

  4. Bistability between Equatorial and Axial Dipoles during Magnetic Field Reversals Christophe Gissinger,1

    E-Print Network [OSTI]

    Gissinger, Christophe

    's dynamo. DOI: 10.1103/PhysRevLett.108.234501 PACS numbers: 91.25.Cw, 47.20.Ky, 47.65.Àd, 52.65.Kj by a turbulent von Ka´rma´n swirling flow of liquid sodium due to two counter-rotating bladed disks [4

  5. Laser cooling in the Penning trap: an analytical model for cooling rates in the presence of an axializing field

    E-Print Network [OSTI]

    R. J. Hendricks; E. S. Phillips; D. M. Segal; R. C. Thompson

    2007-09-24

    Ions stored in Penning traps may have useful applications in the field of quantum information processing. There are, however, difficulties associated with the laser cooling of one of the radial motions of ions in these traps, namely the magnetron motion. The application of a small radio-frequency quadrupolar electric potential resonant with the sum of the two radial motional frequencies has been shown to couple these motions and to lead to more efficient laser cooling. We present an analytical model that enables us to determine laser cooling rates in the presence of such an 'axializing' field. It is found that this field leads to an averaging of the laser cooling rates for the two motions and hence improves the overall laser cooling efficiency. The model also predicts shifts in the motional frequencies due to the axializing field that are in qualitative agreement with those measured in recent experiments. It is possible to determine laser cooling rates experimentally by studying the phase response of the cooled ions to a near resonant excitation field. Using the model developed in this paper, we study the expected phase response when an axializing field is present.

  6. Axial and transverse acoustic radiation forces on a fluid sphere placed arbitrarily in Bessel beam standing wave tweezers

    SciTech Connect (OSTI)

    Mitri, F.G.

    2014-03-15

    The axial and transverse radiation forces on a fluid sphere placed arbitrarily in the acoustical field of Bessel beams of standing waves are evaluated. The three-dimensional components of the time-averaged force are expressed in terms of the beam-shape coefficients of the incident field and the scattering coefficients of the fluid sphere using a partial-wave expansion (PWE) method. Examples are chosen for which the standing wave field is composed of either a zero-order (non-vortex) Bessel beam, or a first-order Bessel vortex beam. It is shown here, that both transverse and axial forces can push or pull the fluid sphere to an equilibrium position depending on the chosen size parameter ka (where k is the wave-number and a the sphere’s radius). The corresponding results are of particular importance in biophysical applications for the design of lab-on-chip devices operating with Bessel beams standing wave tweezers. Moreover, potential investigations in acoustic levitation and related applications in particle rotation in a vortex beam may benefit from the results of this study. -- Highlights: •The axial and transverse forces on a fluid sphere in acoustical Bessel beams tweezers are evaluated. •The attraction or repulsion to an equilibrium position in the standing wave field is examined. •Potential applications are in particle manipulation using standing waves.

  7. Convective cores in galactic cooling flows

    E-Print Network [OSTI]

    A. Kritsuk; T. Plewa; E. Mueller

    2001-05-02

    We use hydrodynamic simulations with adaptive grid refinement to study the dependence of hot gas flows in X-ray luminous giant elliptical galaxies on the efficiency of heat supply to the gas. We consider a number of potential heating mechanisms including Type Ia supernovae and sporadic nuclear activity of a central supermassive black hole. As a starting point for this research we use an equilibrium hydrostatic recycling model (Kritsuk 1996). We show that a compact cooling inflow develops, if the heating is slightly insufficient to counterbalance radiative cooling of the hot gas in the central few kiloparsecs. An excessive heating in the centre, instead, drives a convectively unstable outflow. We model the onset of the instability and a quasi-steady convective regime in the core of the galaxy in two-dimensions assuming axial symmetry. Provided the power of net energy supply in the core is not too high, the convection remains subsonic. The convective pattern is dominated by buoyancy driven large-scale mushroom-like structures. Unlike in the case of a cooling inflow, the X-ray surface brightness of an (on average) isentropic convective core does not display a sharp maximum at the centre. A hybrid model, which combines a subsonic peripheral cooling inflow with an inner convective core, appears to be stable. We also discuss observational implications of these results.

  8. Dynamics of multiple viscoelastic carbon nanotube based nanocomposites with axial magnetic field

    SciTech Connect (OSTI)

    Karli?i?, Danilo; Caji?, Milan; Murmu, Tony; Kozi?, Predrag; Adhikari, Sondipon

    2014-06-21

    Nanocomposites and magnetic field effects on nanostructures have received great attention in recent years. A large amount of research work was focused on developing the proper theoretical framework for describing many physical effects appearing in structures on nanoscale level. Great step in this direction was successful application of nonlocal continuum field theory of Eringen. In the present paper, the free transverse vibration analysis is carried out for the system composed of multiple single walled carbon nanotubes (MSWCNT) embedded in a polymer matrix and under the influence of an axial magnetic field. Equivalent nonlocal model of MSWCNT is adopted as viscoelastically coupled multi-nanobeam system (MNBS) under the influence of longitudinal magnetic field. Governing equations of motion are derived using the Newton second low and nonlocal Rayleigh beam theory, which take into account small-scale effects, the effect of nanobeam angular acceleration, internal damping and Maxwell relation. Explicit expressions for complex natural frequency are derived based on the method of separation of variables and trigonometric method for the “Clamped-Chain” system. In addition, an analytical method is proposed in order to obtain asymptotic damped natural frequency and the critical damping ratio, which are independent of boundary conditions and a number of nanobeams in MNBS. The validity of obtained results is confirmed by comparing the results obtained for complex frequencies via trigonometric method with the results obtained by using numerical methods. The influence of the longitudinal magnetic field on the free vibration response of viscoelastically coupled MNBS is discussed in detail. In addition, numerical results are presented to point out the effects of the nonlocal parameter, internal damping, and parameters of viscoelastic medium on complex natural frequencies of the system. The results demonstrate the efficiency of the suggested methodology to find the closed form solutions for the free vibration response of multiple nanostructure systems under the influence of magnetic field.

  9. Balanced Flow Geostrophic, Inertial, Gradient, and Cyclostrophic Flow

    E-Print Network [OSTI]

    Hennon, Christopher C.

    Balanced Flow Geostrophic, Inertial, Gradient, and Cyclostrophic Flow The types of atmospheric flows describe here have the following characteristics: 1) Steady state (meaning that the flows do surfaces) These are "idealized" flows, created by balances of horizontal forces. They provide a qualitative

  10. Productivity & Energy Flow

    E-Print Network [OSTI]

    Mitchell, Randall J.

    1 Productivity & Energy Flow Ecosystem approach, focuses: on flow of energy, water, and nutrients (capture) of energy by autotrophs Gross (total) Net (total ­ costs) Secondary productivity- capture of energy by herbivores http://sciencebitz.com/?page_id=204 What Controls the Primary Productivity

  11. Elbow mass flow meter

    DOE Patents [OSTI]

    McFarland, A.R.; Rodgers, J.C.; Ortiz, C.A.; Nelson, D.C.

    1994-08-16

    The present invention includes a combination of an elbow pressure drop generator and a shunt-type mass flow sensor for providing an output which gives the mass flow rate of a gas that is nearly independent of the density of the gas. For air, the output is also approximately independent of humidity. 3 figs.

  12. Microelectromechanical flow control apparatus

    SciTech Connect (OSTI)

    Okandan, Murat (NE Albuquerque, NM)

    2009-06-02

    A microelectromechanical (MEM) flow control apparatus is disclosed which includes a fluid channel formed on a substrate from a first layer of a nonconducting material (e.g. silicon nitride). A first electrode is provided on the first layer of the nonconducting material outside the flow channel; and a second electrode is located on a second layer of the nonconducting material above the first layer. A voltage applied between the first and second electrodes deforms the fluid channel to increase its cross-sectional size and thereby increase a flow of a fluid through the channel. In certain embodiments of the present invention, the fluid flow can be decreased or stopped by applying a voltage between the first electrode and the substrate. A peristaltic pumping of the fluid through the channel is also possible when the voltage is applied in turn between a plurality of first electrodes and the substrate. A MEM flow control assembly can also be formed by providing one or more MEM flow control devices on a common substrate together with a submicron filter. The MEM flow control assembly can optionally include a plurality of pressure sensors for monitoring fluid pressure and determining flow rates through the assembly.

  13. Ultrahigh speed 1050nm swept source / Fourier domain OCT retinal and anterior segment imaging at 100,000 to 400,000 axial scans per second

    E-Print Network [OSTI]

    Potsaid, Benjamin M.

    We demonstrate ultrahigh speed swept source/Fourier domain ophthalmic OCT imaging using a short cavity swept laser at 100,000 – 400,000 axial scan rates. Several design configurations illustrate tradeoffs in imaging speed, ...

  14. Hybrid experimental-numerical determination of the loading path to fracture in TRIP780 sheets subjected to multi-axial loading

    E-Print Network [OSTI]

    Dunand, Matthieu

    2010-01-01

    The development of ductile fracture models of metals requires reliable measurements of the stress and strain histories up to the onset of fracture in multi-axial experiments. In the present work, a hybrid experimental-numerical ...

  15. Conductive and convective heat transfer in fluid flows between differentially heated and rotating cylinders

    E-Print Network [OSTI]

    Lopez, Jose M; Avila, Marc

    2015-01-01

    The flow of fluid confined between a heated rotating cylinder and a cooled stationary cylinder is a canonical experiment for the study of heat transfer in engineering. The theoretical treatment of this system is greatly simplified if the cylinders are assumed to be of infinite length or periodic in the axial direction, in which cases heat transfer occurs only through conduction as in a solid. We here investigate numerically heat transfer and the onset of turbulence in such flows by using both periodic and no-slip boundary conditions in the axial direction. We obtain a simple linear criterion that determines whether the infinite-cylinder assumption can be employed. The curvature of the cylinders enters this linear relationship through the slope and additive constant. For a given length-to-gap aspect ratio there is a critical Rayleigh number beyond which the laminar flow in the finite system is convective and so the behaviour is entirely different from the periodic case. The criterion does not depend on the Pra...

  16. Effect of flow fluctuations and nonflow on elliptic flow methods

    E-Print Network [OSTI]

    Ollitrault, Jean-Yves

    2009-01-01

    24.10.Nz I. INTRODUCTION II. FLOW METHODS Elliptic ?ow hasin the participant plane. Flow methods involve variousow e?ects are negligible. Flow ?uctuations modify both the

  17. A flowing plasma model to describe drift waves in a cylindrical helicon discharge

    SciTech Connect (OSTI)

    Chang, L.; Hole, M. J.; Corr, C. S.

    2011-04-15

    A two-fluid model developed originally to describe wave oscillations in the vacuum arc centrifuge, a cylindrical, rapidly rotating, low temperature, and confined plasma column, is applied to interpret plasma oscillations in a RF generated linear magnetized plasma [WOMBAT (waves on magnetized beams and turbulence)], with similar density and field strength. Compared to typical centrifuge plasmas, WOMBAT plasmas have slower normalized rotation frequency, lower temperature, and lower axial velocity. Despite these differences, the two-fluid model provides a consistent description of the WOMBAT plasma configuration and yields qualitative agreement between measured and predicted wave oscillation frequencies with axial field strength. In addition, the radial profile of the density perturbation predicted by this model is consistent with the data. Parameter scans show that the dispersion curve is sensitive to the axial field strength and the electron temperature, and the dependence of oscillation frequency with electron temperature matches the experiment. These results consolidate earlier claims that the density and floating potential oscillations are a resistive drift mode, driven by the density gradient. To our knowledge, this is the first detailed physics model of flowing plasmas in the diffusion region away from the RF source. Possible extensions to the model, including temperature nonuniformity and magnetic field oscillations, are also discussed.

  18. OPTIMIZATION OF COAL PARTICLE FLOW PATTERNS IN LOW NOX BURNERS

    SciTech Connect (OSTI)

    Jost O.L. Wendt; Gregory E. Ogden; Jennifer Sinclair; Stephanus Budilarto

    2001-09-04

    It is well understood that the stability of axial diffusion flames is dependent on the mixing behavior of the fuel and combustion air streams. Combustion aerodynamic texts typically describe flame stability and transitions from laminar diffusion flames to fully developed turbulent flames as a function of increasing jet velocity. Turbulent diffusion flame stability is greatly influenced by recirculation eddies that transport hot combustion gases back to the burner nozzle. This recirculation enhances mixing and heats the incoming gas streams. Models describing these recirculation eddies utilize conservation of momentum and mass assumptions. Increasing the mass flow rate of either fuel or combustion air increases both the jet velocity and momentum for a fixed burner configuration. Thus, differentiating between gas velocity and momentum is important when evaluating flame stability under various operating conditions. The research efforts described herein are part of an ongoing project directed at evaluating the effect of flame aerodynamics on NO{sub x} emissions from coal fired burners in a systematic manner. This research includes both experimental and modeling efforts being performed at the University of Arizona in collaboration with Purdue University. The objective of this effort is to develop rational design tools for optimizing low NO{sub x} burners. Experimental studies include both cold-and hot-flow evaluations of the following parameters: primary and secondary inlet air velocity, coal concentration in the primary air, coal particle size distribution and flame holder geometry. Hot-flow experiments will also evaluate the effect of wall temperature on burner performance.

  19. Analysis of Developing Gas/liquid Two-Phase Flows

    SciTech Connect (OSTI)

    Elena A. Tselishcheva; Michael Z. Podowski; Steven P. Antal; Donna Post Guillen; Matthias Beyer; Dirk Lucas

    2010-06-01

    The goal of this work is to develop a mechanistically based CFD model that can be used to simulate process equipment operating in the churn-turbulent regime. The simulations were performed using a state-of-the-art computational multiphase fluid dynamics code, NPHASE–CMFD [Antal et al,2000]. A complete four-field model, including the continuous liquid field and three dispersed gas fields representing bubbles of different sizes, was first carefully tested for numerical convergence and accuracy, and then used to reproduce the experimental results from the TOPFLOW test facility at Forschungszentrum Dresden-Rossendorf e.V. Institute of Safety Research [Prasser et al,2007]. Good progress has been made in simulating the churn-turbulent flows and comparison the NPHASE-CMFD simulations with TOPFLOW experimental data. The main objective of the paper is to demonstrate capability to predict the evolution of adiabatic churn-turbulent gas/liquid flows. The proposed modelling concept uses transport equations for the continuous liquid field and for dispersed bubble fields [Tselishcheva et al, 2009]. Along with closure laws based on interaction between bubbles and continuous liquid, the effect of height on air density has been included in the model. The figure below presents the developing flow results of the study, namely total void fraction at different axial locations along the TOPFLOW facility test section. The complete model description, as well as results of simulations and validation will be presented in the full paper.

  20. Bedrock Erosion by Granular Flow

    E-Print Network [OSTI]

    Hsu, Leslie

    2010-01-01

    of boulders later in the flow when the matrix has thickenedMaximum height of the flow is 3.3 m. Appendix A true storyThe physics of debris flows, Reviews of Geophysics 35(3),

  1. Magnetically stimulated fluid flow patterns

    SciTech Connect (OSTI)

    Martin, Jim; Solis, Kyle

    2014-03-06

    Sandia National Laboratories' Jim Martin and Kyle Solis explain research on the effects of magnetic fields on fluid flows and how they stimulate vigorous flows. Fluid flow is a necessary phenomenon in everything from reactors to cooling engines in cars.

  2. Magnetically stimulated fluid flow patterns

    ScienceCinema (OSTI)

    Martin, Jim; Solis, Kyle

    2014-08-06

    Sandia National Laboratories' Jim Martin and Kyle Solis explain research on the effects of magnetic fields on fluid flows and how they stimulate vigorous flows. Fluid flow is a necessary phenomenon in everything from reactors to cooling engines in cars.

  3. Redox Flow Batteries, a Review

    E-Print Network [OSTI]

    Weber, Adam Z.

    2013-01-01

    of a Vanadium Redox-Flow Battery to Maintain Power Quality,"Fuel System Using Redox Flow Battery," ed: WO Patentand D. B. Hickey, "Redox Flow Battery System for Distributed

  4. Controls of Wellbore Flow Regimes on Pump Effluent Composition

    SciTech Connect (OSTI)

    James Martin-Hayden; plummer; Sanford Britt

    2014-01-01

    Where well water and formation water are compositionally different or heterogeneous, pump effluent composition will vary due to partial mixing and transport induced by pumping. Investigating influences of purging and sampling methodology on composition variability requires quantification of wellbore flow regimes and mixing. As a basis for this quantification, analytical models simulating Poiseuille flow were developed to calculate flow paths and travel times. Finite element modeling was used to incorporate influences of mixing. Parabolic velocity distributions within the screened interval accelerate with cumulative inflow approaching the pump intake while an annulus of inflowing formation water contracts uniformly to displace an axial cylinder of pre-pumping well water as pumping proceeds. Increased dispersive mixing forms a more diffuse formation water annulus and the contribution of formation water to pump effluent increases more rapidly. Models incorporating viscous flow and diffusion scale mixing show that initially pump effluent is predominantly pre-pumping well water and compositions vary most rapidly. After two screen volumes of pumping, 94% of pump effluent is inflowing formation water. Where the composition of formation water and pre-pumping well water are likely to be similar, pump effluent compositions will not vary significantly and may be collected during early purging or with passive sampling. However, where these compositions are expected to be considerably different or heterogeneous, compositions would be most variable during early pumping, that is, when samples are collected during low-flow sampling. Purging of two screen volumes would be required to stabilize the content and collect a sample consisting of 94% formation water.

  5. Enviro Hurdles: Instream Flow | Department of Energy

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

    Hurdles: Instream Flow Enviro Hurdles: Instream Flow Enviro Hurdles: Instream Flow 76enviornlbevelhimer4.pptx More Documents & Publications Instream Flow Project Development and...

  6. Flow Map Manager 

    E-Print Network [OSTI]

    Moya, Maria J

    2011-11-24

    Long-distance bus companies, operate services along routes which have a flow of passengers. Along a route some passengers will leave the bus while others join. To monitor demand sufficiently well a tool is required which can help estimate...

  7. Complex Flow Workshop Report

    SciTech Connect (OSTI)

    none,

    2012-05-01

    This report documents findings from a workshop on the impacts of complex wind flows in and out of wind turbine environments, the research needs, and the challenges of meteorological and engineering modeling at regional, wind plant, and wind turbine scales.

  8. Optical flow switching

    E-Print Network [OSTI]

    Chan, Vincent W. S.

    Present-day networks are being challenged by dramatic increases in bandwidth demand of emerging applications. We will explore a new transport, ldquooptical flow switchingrdquo, that will enable significant growth and ...

  9. Parallel flow diffusion battery

    DOE Patents [OSTI]

    Yeh, H.C.; Cheng, Y.S.

    1984-01-01

    A parallel flow diffusion battery for determining the mass distribution of an aerosol has a plurality of diffusion cells mounted in parallel to an aerosol stream, each diffusion cell including a stack of mesh wire screens of different density.

  10. Parallel flow diffusion battery

    DOE Patents [OSTI]

    Yeh, Hsu-Chi (Albuquerque, NM); Cheng, Yung-Sung (Albuquerque, NM)

    1984-08-07

    A parallel flow diffusion battery for determining the mass distribution of an aerosol has a plurality of diffusion cells mounted in parallel to an aerosol stream, each diffusion cell including a stack of mesh wire screens of different density.

  11. Electrochemical flow capacitors

    DOE Patents [OSTI]

    Gogotsi, Yury; Presser, Volker; Kumbar, Emin Caglan

    2015-11-05

    The present invention generally relates to devices for energy storage technologies, and more particularly to electrochemical flow capacitor systems and applications. In some aspects, these flow capacitors have at least one electrode comprising a non-stationary solid or semi-solid composition comprising supercapacitive particles and an electrolytic solvent in electrical communication with at least one current collector, and energy is stored and/or released by charging and/or discharging the electrode(s).

  12. Electrochemical flow capacitors

    DOE Patents [OSTI]

    Gogotsi, Yury; Presser, Volker; Kumbur, Emin Caglan

    2015-10-27

    The present invention generally relates to devices for energy storage technologies, and more particularly to electrochemical flow capacitor systems and applications. In some aspects, these flow capacitors have at least one electrode comprising a non-stationary solid or semi-solid composition comprising supercapacitive particles and an electrolytic solvent in electrical communication with at least one current collector, and energy is stored and/or released by charging and/or discharging the electrode(s).

  13. The cool component and the dichotomy, lateral expansion, and axial rotation of solar X-ray jets

    SciTech Connect (OSTI)

    Moore, Ronald L.; Sterling, Alphonse C.; Falconer, David A.; Robe, Dominic

    2013-06-01

    We present results from a study of 54 polar X-ray jets that were observed in coronal X-ray movies from the X-ray Telescope on Hinode and had simultaneous coverage in movies of the cooler transition region (T ? 10{sup 5} K) taken in the He II 304 Å band of the Atmospheric Imaging Assembly (AIA) on Solar Dynamics Observatory. These dual observations verify the standard-jet/blowout-jet dichotomy of polar X-ray jets previously found primarily from XRT movies alone. In accord with models of blowout jets and standard jets, the AIA 304 Å movies show a cool (T ? 10{sup 5} K) component in nearly all blowout X-ray jets and in a small minority of standard X-ray jets, obvious lateral expansion in blowout X-ray jets but none in standard X-ray jets, and obvious axial rotation in both blowout X-ray jets and standard X-ray jets. In our sample, the number of turns of axial rotation in the cool-component standard X-ray jets is typical of that in the blowout X-ray jets, suggesting that the closed bipolar magnetic field in the jet base has substantial twist not only in all blowout X-ray jets but also in many standard X-ray jets. We point out that our results for the dichotomy, lateral expansion, and axial rotation of X-ray jets add credence to published speculation that type-II spicules are miniature analogs of X-ray jets, are generated by granule-size emerging bipoles, and thereby carry enough energy to power the corona and solar wind.

  14. Conjugate flow action functionals

    E-Print Network [OSTI]

    Daniele Venturi

    2013-10-15

    We present a new general method to construct an action functional for a non-potential field theory. The key idea relies on representing the governing equations of the theory relative to a diffeomorphic flow of curvilinear coordinates which is assumed to be functionally dependent on the solution field. Such flow, which will be called the conjugate flow of the theory, evolves in space and time similarly to a physical fluid flow of classical mechanics and it can be selected in order to symmetrize the Gateaux derivative of the field equations with respect to suitable local bilinear forms. This is equivalent to requiring that the governing equations of the field theory can be derived from a principle of stationary action on a Lie group manifold. By using a general operator framework, we obtain the determining equations of such manifold and the corresponding conjugate flow action functional. In particular, we study scalar and vector field theories governed by second-order nonlinear partial differential equations. The identification of transformation groups leaving the conjugate flow action functional invariant could lead to the discovery of new conservation laws in fluid dynamics and other disciplines.

  15. Computational Modeling of Blood Flow in the TrapEase Inferior Vena Cava Filter

    SciTech Connect (OSTI)

    Singer, M A; Henshaw, W D; Wang, S L

    2008-02-04

    To evaluate the flow hemodynamics of the TrapEase vena cava filter using three dimensional computational fluid dynamics, including simulated thrombi of multiple shapes, sizes, and trapping positions. The study was performed to identify potential areas of recirculation and stagnation and areas in which trapped thrombi may influence intrafilter thrombosis. Computer models of the TrapEase filter, thrombi (volumes ranging from 0.25mL to 2mL, 3 different shapes), and a 23mm diameter cava were constructed. The hemodynamics of steady-state flow at Reynolds number 600 was examined for the unoccluded and partially occluded filter. Axial velocity contours and wall shear stresses were computed. Flow in the unoccluded TrapEase filter experienced minimal disruption, except near the superior and inferior tips where low velocity flow was observed. For spherical thrombi in the superior trapping position, stagnant and recirculating flow was observed downstream of the thrombus; the volume of stagnant flow and the peak wall shear stress increased monotonically with thrombus volume. For inferiorly trapped spherical thrombi, marked disruption to the flow was observed along the cava wall ipsilateral to the thrombus and in the interior of the filter. Spherically shaped thrombus produced a lower peak wall shear stress than conically shaped thrombus and a larger peak stress than ellipsoidal thrombus. We have designed and constructed a computer model of the flow hemodynamics of the TrapEase IVC filter with varying shapes, sizes, and positions of thrombi. The computer model offers several advantages over in vitro techniques including: improved resolution, ease of evaluating different thrombus sizes and shapes, and easy adaptation for new filter designs and flow parameters. Results from the model also support a previously reported finding from photochromic experiments that suggest the inferior trapping position of the TrapEase IVC filter leads to an intra-filter region of recirculating/stagnant flow with very low shear stress that may be thrombogenic.

  16. Strong Room-temperature Negative Transconductance In An Axial Si/Ge Hetero-nanowire Tunneling Field-effect Transistor

    SciTech Connect (OSTI)

    Zhang, Peng; Le, Son T.; Hou, Xiaoxiao; Zaslavsky, A.; Perea, Daniel E.; Dayeh, Shadi A.; Picraux, Samuel T.

    2014-08-11

    We report on room-temperature negative transconductance (NTC) in axial Si/Ge hetero-nanowire tunneling field-effect transistors (TFETs). The NTC produces a current peak-to-valley ratio > 45, a high value for a Si-based device. We characterize the NTC characteristics over a range of gate VG and drain VD voltages, finding that NTC persists down to VD = –50 mV. The physical mechanism responsible for the NTC is the VG-induced depletion in the p-Ge section that eventually reduces the maximum electric field that triggers the tunneling ID, as confirmed via three-dimensional TCAD simulations.

  17. Observation of Pseudoscalar and Axial Vector Resonances in pi- p -> K+ K- pi0 n at 18 GeV

    E-Print Network [OSTI]

    Adams, G S

    2001-01-01

    A new measurement of the reaction pi- p -> K+ K- pi0 n has been made at a beam energy of 18 GeV. A partial wave analysis of the K+ K- pi0 system shows evidence for three pseudoscalar resonances, eta(1295), eta(1416), and eta(1485), as well as two axial vectors, f1(1285), and f1(1420). Their observed masses, widths and decay properties are reported. No signal was observed for C(1480), an IG J{PC} = 1+ 1{--} state previously reported in phi pi0 decay.

  18. Limiting current of axisymmetric relativistic charged-particle beam propagating in strong axial magnetic field in coaxial drift tube

    SciTech Connect (OSTI)

    Yatsenko, T.; Ilyenko, K.; Sotnikov, G. V.

    2012-06-15

    In the strong axial magnetic field approximation, we calculate the space-charge limited (SCL) current of axisymmetric relativistic charged-particle beam in a coaxial drift tube of finite length. Results are compared to analytical estimates and numerical modeling of SCL current in the infinitely long drift tube. For the infinitely long drift tube, which inner conductor is biased and the outer conductor is lined with a finite-width dielectric insert, analytic approximations for the SCL current in the bias voltage are developed.

  19. Electrochemical cell apparatus having axially distributed entry of a fuel-spent fuel mixture transverse to the cell lengths

    DOE Patents [OSTI]

    Reichner, P.; Dollard, W.J.

    1991-01-08

    An electrochemical apparatus is made having a generator section containing axially elongated electrochemical cells, a fresh gaseous feed fuel inlet, a gaseous feed oxidant inlet, and at least one gaseous spent fuel exit channel, where the spent fuel exit channel passes from the generator chamber to combine with the fresh feed fuel inlet at a mixing apparatus, reformable fuel mixture channel passes through the length of the generator chamber and connects with the mixing apparatus, that channel containing entry ports within the generator chamber, where the axis of the ports is transverse to the fuel electrode surfaces, where a catalytic reforming material is distributed near the reformable fuel mixture entry ports. 2 figures.

  20. PWR FLECHT SEASET 21-rod bundle flow blockage task data and analysis report. NRC/EPRI/Westinghouse Report No. 11. Appendices K-P

    SciTech Connect (OSTI)

    Loftus, M.J.; Hochreiter, L.E.; Lee, N.; McGuire, M.F.; Wenzel, A.H.; Valkovic, M.M.

    1982-09-01

    This report presents data and limited analysis from the 21-Rod Bundle Flow Blockage Task of the Full-Length Emergency Cooling Heat Transfer Separate Effects and Systems Effects Test Program (FLECHT SEASET). The tests consisted of forced and gravity reflooding tests utilizing electrical heater rods with a cosine axial power profile to simulate PWR nuclear core fuel rod arrays. Steam cooling and hydraulic characteristics tests were also conducted. These tests were utilized to determine effects of various flow blockage configurations (shapes and distributions) on reflooding behavior, to aid in development/assessment of computational models in predicting reflooding behavior of flow blockage configurations, and to screen flow blockage configurations for future 163-rod flow blockage bundle tests.

  1. Fluid Flow Estimation Through Integration of Physical Flow Configurations

    E-Print Network [OSTI]

    Garbe, Christoph S.

    Fluid Flow Estimation Through Integration of Physical Flow Configurations Christoph S. Garbe IWR, University of Heidelberg Christoph.Garbe@iwr.uni-heidelberg.de Abstract. The measurement of fluid flows is an emerging field for op- tical flow computation. In a number of such applications, a tracer is visualized

  2. Energy Flow Energy Flow Energy Flow A.Ukleja, T.Tymieniecka, I.Skillicorn 1 Azimuthal asymmetry

    E-Print Network [OSTI]

    Energy Flow Energy Flow Energy Flow A.Ukleja, T.Tymieniecka, I.Skillicorn 1 Azimuthal asymmetry using energy flow method Azimuthal angle distribution at Q2 >100 GeV2 Energy flow method.Ukleja on behalf of the ZEUS Collaboration #12; Energy Flow Energy Flow Energy Flow A.Ukleja, T.Tymieniecka, I

  3. Flow Batteries A Historical Perspective

    E-Print Network [OSTI]

    Flow Batteries A Historical Perspective Robert F. Savinell Case Western Reserve University Department of Chemical Engineering DOE Flow Battery Workshop March 2012 #12;2 OUTLINE ·The first flow cell? ·Review articles- documented progress ·Early NASA Work- some learning ·Fuel Cell and Flow Battery

  4. Two-phase flow studies

    SciTech Connect (OSTI)

    Hanold, R.J.

    1983-12-01

    The two-phase flow program is directed at understanding the hydrodynamics of two-phase flows. The two-phase flow regime is characterized by a series of flow patterns that are designated as bubble, slug, churn, and annular flow. Churn flow has received very little scientific attention. This lack of attention cannot be justified because calculations predict that the churn flow pattern will exist over a substantial portion of the two-phase flow zone in producing geothermal wells. The University of Houston is experimentally investigating the dynamics of churn flow and is measuring the holdup over the full range of flow space for which churn flow exists. These experiments are being conducted in an air/water vertical two-phase flow loop. Brown University has constructed and is operating a unique two-phase flow research facility specifically designed to address flow problems of relevance to the geothermal industry. An important feature of the facility is that it is dedicated to two-phase flow of a single substance (including evaporation and condensation) as opposed to the case of a two-component two-phase flow. This facility can be operated with horizontal or vertical test sections of constant diameter or with step changes in diameter to simulate a geothermal well profile.

  5. Experimental Investigation of the Root Cause Mechanism and Effectiveness of Mitigating Actions for Axial Offset Anomaly in Pressurized Water Reactors

    SciTech Connect (OSTI)

    Said Abdel-Khalik

    2005-07-02

    Axial offset anomaly (AOA) in pressurized water reactors refers to the presence of a significantly larger measured negative axial offset deviation than predicted by core design calculations. The neutron flux depression in the upper half of high-power rods experiencing significant subcooled boiling is believed to be caused by the concentration of boron species within the crud layer formed on the cladding surface. Recent investigations of the root-cause mechanism for AOA [1,2] suggest that boron build-up on the fuel is caused by precipitation of lithium metaborate (LiBO2) within the crud in regions of subcooled boiling. Indirect evidence in support of this hypothesis was inferred from operating experience at Callaway, where lithium return and hide-out were, respectively, observed following power reductions and power increases when AOA was present. However, direct evidence of lithium metaborate precipitation within the crud has, heretofore, not been shown because of its retrograde solubility. To this end, this investigation has been undertaken in order to directly verify or refute the proposed root-cause mechanism of AOA, and examine the effectiveness of possible mitigating actions to limit its impact in high power PWR cores.

  6. Multiphase cooling flows

    E-Print Network [OSTI]

    Peter A. Thomas

    1996-08-20

    I discuss the multiphase nature of the intracluster medium whose neglect can lead to overestimates of the baryon fraction of clusters by up to a factor of two. The multiphase form of the cooling flow equations are derived and reduced to a simple form for a wide class of self-similar density distributions. It is shown that steady-state cooling flows are \\emph{not} consistent with all possible emissivity profiles which can therefore be used as a test of the theory. In combination, they provide strong constraints on the mass distribution within the cooling radius.

  7. Variable Refrigerant Flow HVAC 

    E-Print Network [OSTI]

    Jones, S.

    2013-01-01

    Variable refrigerant flow technology HVAC CATEE 2013 San Antonio, TX ESL-KT-13-12-33 CATEE 2013: Clean Air Through Energy Efficiency Conference, San Antonio, Texas Dec. 16-18 What is the acronym VRF? ? Variable Refrigerant Flow Operates like a... heat pump utilizing VFD Inverter Compressors and LEV’s Unlike conventional commercial and residential HVAC systems in the USA The predominate method of cooling and heating in the world ESL-KT-13-12-33 CATEE 2013: Clean Air Through Energy Efficiency...

  8. Spraying Powder Materials by the High-Enthalpy Laminar Plasma Flow

    SciTech Connect (OSTI)

    Khutsishvili, M.; Kikvadze, L.

    2008-03-19

    One of the most promising engineering solutions of the problem of spraying powder materials is the proposed method of plasma spraying by the laminar plasma jet. Laminar plasma flow is characterized by small jet angle divergence; the powder particles are penetrated and accelerated mainly in the axial direction. The molten powder particles are transported almost to the surface of a treated work-piece inside the laminar plasma flow in an atmosphere of the plasma-forming gas with the acceleration on the entire transfer area, which leads to an increase in the particles velocity, a decrease of their oxidability, an increase in the powder deposition efficiency, density, adhesion strength with the surface to be coated.

  9. What flows in the chiral magnetic effect? -- Simulating the particle production with CP-breaking backgrounds

    E-Print Network [OSTI]

    Kenji Fukushima

    2015-08-23

    To address a question of whether the chiral magnetic current is a static polarization or a genuine flow of charged particles, we elucidate the numerical formulation to simulate the net production of right-handed particles and anomalous currents with CP-breaking background fields which cause an imbalance between particles and anti-particles. For a concrete demonstration we numerically impose pulsed electric and magnetic fields to confirm our answer to the question that the produced net particles flow in the dynamical chiral magnetic effect. The rate for the particle production and the chiral magnetic current generation is quantitatively consistent with the axial anomaly, while they appear with a finite response time. We emphasize the importance to quantify the response time that would suppress observable effects of the anomalous current.

  10. Magnetic field distribution in the plasma flow generated by a plasma focus discharge

    SciTech Connect (OSTI)

    Mitrofanov, K. N.; Krauz, V. I. Myalton, V. V.; Velikhov, E. P.; Vinogradov, V. P.; Vinogradova, Yu. V.

    2014-11-15

    The magnetic field in the plasma jet propagating from the plasma pinch region along the axis of the chamber in a megajoule PF-3 plasma focus facility is studied. The dynamics of plasma with a trapped magnetic flow is analyzed. The spatial sizes of the plasma jet region in which the magnetic field concentrates are determined in the radial and axial directions. The magnetic field configuration in the plasma jet is investigated: the radial distribution of the azimuthal component of the magnetic field inside the jet is determined. It is shown that the magnetic induction vector at a given point in space can change its direction during the plasma flight. Conclusions regarding the symmetry of the plasma flow propagation relative to the chamber axis are drawn.

  11. Loss mechanisms in turbine tip clearance flows

    E-Print Network [OSTI]

    Huang, Arthur (Arthur C.)

    2011-01-01

    Numerical simulations of tip clearance ow have been carried out to dene the loss generation mechanisms associated with tip leakage in unshrouded axial turbines. Mix- ing loss between the leakage, which takes the form of a ...

  12. Studies on the effect of the axial magnetic field on the x-ray bremsstrahlung in a 2.45 GHz permanent magnet microwave ion source

    SciTech Connect (OSTI)

    Kumar, Narender; Rodrigues, G., E-mail: gerosro@gmail.com; Lakshmy, P. S.; Mathur, Y.; Ahuja, R.; Kanjilal, D. [Inter University Accelerator Centre, Aruna Asaf Ali Marg, New Delhi (India)] [Inter University Accelerator Centre, Aruna Asaf Ali Marg, New Delhi (India); Baskaran, R. [Indira Gandhi Centre for Atomic Research, Kalpakkam, Tamilnadu (India)] [Indira Gandhi Centre for Atomic Research, Kalpakkam, Tamilnadu (India)

    2014-02-15

    A compact microwave ion source has been designed and developed for operation at a frequency of 2.45 GHz. The axial magnetic field is based on two permanent magnet rings, operating in the “off-resonance” mode and is tunable by moving the permanent magnets. In order to understand the electron energy distribution function, x-ray bremsstrahlung has been measured in the axial direction. Simulation studies on the x-ray bremsstrahlung have been carried out to compare with the experimental results. The effect of the axial magnetic field with respect to the microwave launching position and the position of the extraction electrode on the x-ray bremsstrahlung have been studied.

  13. The symmetry of the energy momentum tensor does not necessarily reflect the space-time symmetry: a viscous axially symmetric cosmological solution

    E-Print Network [OSTI]

    Fatemeh Bagheri; Reza Mansouri

    2014-08-03

    Applying the method of conformal metric to a given static axially symmetric vacuum solution of the Einstein equations, we have shown that there is no solution representing a cosmic ideal fluid which is asymtotically FLRW. Letting the cosmic fluid to be imperfect there are axially symmetric solutions tending to FLRW at space infinity. The solution we have found represents an axially symmetric spacetime leading to a spherically symmetric Einstein tensor. Therefore, we have found a solution of Einstein equations representing a spherically symmetric matter distribution corresponding to a spacetime which does not reflect the same symmetry. We have also found another solution of Einstein equation corresponding to the same energy tensor with spherical symmetry.

  14. Improved blade profile loss and deviation angle models for advanced transonic compressor bladings. Part 1: A model for subsonic flow

    SciTech Connect (OSTI)

    Koenig, W.M.; Hennecke, D.K.; Fottner, L.

    1996-01-01

    New blading concepts as used in modern transonic axial-flow compressors require improved loss and deviation angle correlations. The new model presented in this paper incorporates several elements and treats blade-row flows having subsonic and supersonic inlet conditions separately. In the first part of this paper two proved and well-established profile loss correlations for subsonic flows are extended to quasi-two-dimensional conditions and to custom-tailored blade designs. Instead of a deviation angle correlation, a simple method based on singularities is utilized. The comparison between the new model and a recently published model demonstrates the improved accuracy in prediction of cascade performance achieved by the new model.

  15. Flow cytometry apparatus

    DOE Patents [OSTI]

    Pinkel, Daniel (Walnut Creek, CA)

    1991-01-01

    An obstruction across the flow chamber creates a one dimensional convergence of a sheath fluid. A passageway in the construction directs flat cells near to the area of one dimensional convergence in the sheath fluid to provide proper orientation of flat cells at fast rates.

  16. US energy flow, 1991

    SciTech Connect (OSTI)

    Borg, I.Y.; Briggs, C.K.

    1992-06-01

    Trends in energy consumption and assessment of energy sources are discussed. Specific topics discussed include: energy flow charts; comparison of energy use with 1990 and earlier years; supply and demand of fossil fuels (oils, natural gas, coal); electrical supply and demand; and nuclear power.

  17. Flow cytometry apparatus

    DOE Patents [OSTI]

    Pinkel, D.

    1987-11-30

    An obstruction across the flow chamber creates a one-dimensional convergence of a sheath fluid. A passageway in the obstruction directs flat cells near to the area of one-dimensional convergence in the sheath fluid to provide proper orientation of flat cells at fast rates. 6 figs.

  18. ENERGY FLOWS CLIMATE CHANGE

    E-Print Network [OSTI]

    Schwartz, Stephen E.

    ENERGY FLOWS FORCINGS CLIMATE CHANGE A REALLY TOUGH PROBLEM Stephen E. Schwartz, BNL, 7-20-11 www average temperature 15°C or 59°F #12;ATMOSPHERIC RADIATION Power per area Energy per time per area Unit" temperature to radiative flux. #12;GLOBAL ENERGY BALANCE Global and annual average energy fluxes in watts per

  19. Simultaneous determination of the elastic modulus and density/thickness of ultrathin films utilizing micro-/nanoresonators under applied axial force

    SciTech Connect (OSTI)

    Stachiv, I., E-mail: stachiv@fzu.cz [Institute of Physics, Czech Academy of Sciences, Prague (Czech Republic); Advanced Manufacturing Institute with High-Tech Innovations, National Chung Cheng University, Chiayi County, Taiwan (China); Zapomel, J. [Institute of Thermomechanics, Czech Academy of Sciences, Prague (Czech Republic); Chen, Y.-L. [Institute of Physics, Academia Sinica, Taipei, Taiwan (China); Department of Physics, National Taiwan University, Taipei, Taiwan (China); Department of Chemical Engineering, National Tsing-Hua University, Hsinchu, Taiwan (China)

    2014-03-28

    Thin films are widely used in microelectronics, optics, filters, and various sensing devices. We propose a method to simultaneously determine the elastic modulus and density or thickness of ultrathin films deposited on various substrate materials. This methodology utilizes measurement of the resonant frequencies of the micro-/nanoresonator under intentionally applied axial tension and, consequently, the beam to string transition. Elastic modulus and density/thickness of thin film are obtained from the ratio between the resonant frequencies of the nanoresonator with and without applied axial force.

  20. Effects of anisotropy on the performance characteristics of an axially laminated anisotropic-rotor synchronous reluctance motor drive system

    SciTech Connect (OSTI)

    Isaac, F.N.; Arkadan, A.A.; Russell, A.A. [Marquette Univ., Milwaukee, WI (United States)] [Marquette Univ., Milwaukee, WI (United States); El-Antably, A.

    1998-09-01

    In the last few years, increased attention has been paid to the performance characterization and evaluation of the performance of synchronous reluctance machines. Extensive research has concentrated on different rotor structures in order to achieve high performance variable speed drives for applications such as electric vehicles. The effects of accounting for anisotropy on the performance characteristics of Axially Laminated Anisotropic (ALA) rotor Synchronous Reluctance Motor (SynRM) drive systems are studied. These effects are evaluated from the simulations of a computer aided model. The model is based on the use of an iterative approach which indirectly couples a two dimensional (2D) nonlinear finite element (FE) model, which accounts for anisotropy, to a state space model describing the SynRM drive system. The simulation results are also validated by comparison to test data of a prototype ALA rotor SynRM drive system.

  1. Observation of Pseudoscalar and Axial Vector Resonances in pi- p -> K+ K- pi0 n at 18 GeV

    SciTech Connect (OSTI)

    G.S. Adams; T. Adams; Z. Bar-Yam; J.M. Bishop; V.A. Bodyagin; D.S. Brown; N.M. Cason; S.U. Chung; J.P. Cummings; K. Danyo; A.I. Demianov; S. Denisov; V. Dorofeev; J.P. Dowd; P. Eugenio; X.L. Fan; A.M. Gribushin; R.W. Hackenburg; M. Hayek; J. Hu; E.I. Ivanov; D. Joffe; I. Kachaev; W. Kern; E. King; O.L. Kodolova; V.L. Korotkikh; M.A. Kostin; Joachim Kuhn; V. Lipaev; J.M. Losecco; M. Lu; J.J. Manak; J. Napolitano; M. Nozar; C. Olchanski; A.I. Ostrovidov; T.K. Pedlar; A. Popov; D. Ryabchikov; A.H. Sanjari; L.I. Sarycheva; K.K. Seth; N. Shenhav; X. Shen; W.D. Shephard; N.B. Sinev; D.L. Stienike; S.A. Taegar; D.R. Thompson; A. Tomaradze; I.N. Vardanyan; D.P. Weygand; D. White; H.J. Willutzki; A.A. Yershov

    2001-09-01

    The number of pseudoscalar mesons in the mass range from 1400 to 1500 MeV/c{sup 2} has been a subject of considerable interest for many years, with several experiments having presented evidence for two closely spaced states. A new measurement of the reaction {pi}{sup -} p {yields} K{sup +} K{sup -} {pi}{sup 0}n has been made at a beam energy of 18 GeV. A partial wave analysis of the K{sup +} K{sup -} {pi}{sup 0} system shows evidence for three pseudoscalar resonances, {eta}(1295), {eta}(1416), and {eta}(1485), as well as two axial vectors, f{sub 1}(1285), and f{sub 1}(1420). Their observed masses, widths and decay properties are reported. No signal was observed for C(1480), an I{sub G} J{sup PC} = 1{sup +} 1{sup --} state previously reported in {phi}{pi}{sup 0} decay.

  2. 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 20–100 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.

  3. Exact analysis of particle dynamics in combined field of finite duration laser pulse and static axial magnetic field

    SciTech Connect (OSTI)

    Sagar, Vikram; Sengupta, Sudip; Kaw, Predhiman [Institute for Plasma Research, Bhat, Gandhinagar 382428 (India)

    2012-11-15

    Dynamics of a charged particle is studied in the field of a relativistically intense linearly polarized finite duration laser pulse in the presence of a static axial magnetic field. For a finite duration laser pulse whose temporal shape is defined by Gaussian profile, exact analytical expressions are derived for the particle trajectory, momentum, and energy as function of laser phase. From the solutions, it is shown that, unlike for the monochromatic plane wave case, resonant phase locking time between the particle and laser pulse is finite. The net energy transferred to the particle does not increase monotonically but tends to saturate. It is further shown that appropriate tuning of cyclotron frequency of the particle with the characteristic frequency in the pulse spectrum can lead to the generation of accelerated particles with variable energies in MeV-TeV range.

  4. Electrochemical cell apparatus having axially distributed entry of a fuel-spent fuel mixture transverse to the cell lengths

    DOE Patents [OSTI]

    Reichner, Philip (Plum Borough, PA); Dollard, Walter J. (Churchill Borough, PA)

    1991-01-01

    An electrochemical apparatus (10) is made having a generator section (22) containing axially elongated electrochemical cells (16), a fresh gaseous feed fuel inlet (28), a gaseous feed oxidant inlet (30), and at least one gaseous spent fuel exit channel (46), where the spent fuel exit channel (46) passes from the generator chamber (22) to combine with the fresh feed fuel inlet (28) at a mixing apparatus (50), reformable fuel mixture channel (52) passes through the length of the generator chamber (22) and connects with the mixing apparatus (50), that channel containing entry ports (54) within the generator chamber (22), where the axis of the ports is transverse to the fuel electrode surfaces (18), where a catalytic reforming material is distributed near the reformable fuel mixture entry ports (54).

  5. Experimental and Analytic Study on the Core Bypass Flow in a Very High Temperature Reactor

    SciTech Connect (OSTI)

    Richard Schultz

    2012-04-01

    Core bypass flow has been one of key issues in the very high temperature reactor (VHTR) design for securing core thermal margins and achieving target temperatures at the core exit. The bypass flow in a prismatic VHTR core occurs through the control element holes and the radial and axial gaps between the graphite blocks for manufacturing and refueling tolerances. These gaps vary with the core life cycles because of the irradiation swelling/shrinkage characteristic of the graphite blocks such as fuel and reflector blocks, which are main components of a core's structure. Thus, the core bypass flow occurs in a complicated multidimensional way. The accurate prediction of this bypass flow and counter-measures to minimize it are thus of major importance in assuring core thermal margins and securing higher core efficiency. Even with this importance, there has not been much effort in quantifying and accurately modeling the effect of the core bypass flow. The main objectives of this project were to generate experimental data for validating the software to be used to calculate the bypass flow in a prismatic VHTR core, validate thermofluid analysis tools and their model improvements, and identify and assess measures for reducing the bypass flow. To achieve these objectives, tasks were defined to (1) design and construct experiments to generate validation data for software analysis tools, (2) determine the experimental conditions and define the measurement requirements and techniques, (3) generate and analyze the experimental data, (4) validate and improve the thermofluid analysis tools, and (5) identify measures to control the bypass flow and assess its performance in the experiment.

  6. Supercritical flow in rectangular expansions 

    E-Print Network [OSTI]

    Walsh, Peter.

    1968-01-01

    In recent years the occasions for design of channels to contain supercritical flow has increased considerably. Consequently there has developed a need for a method of predicting the physical characteristics of such flow based on theory...

  7. Radial flow pulse jet mixer

    DOE Patents [OSTI]

    VanOsdol, John G.

    2013-06-25

    The disclosure provides a pulse jet mixing vessel for mixing a plurality of solid particles. The pulse jet mixing vessel is comprised of a sludge basin, a flow surface surrounding the sludge basin, and a downcoming flow annulus between the flow surface and an inner shroud. The pulse jet mixing vessel is additionally comprised of an upper vessel pressurization volume in fluid communication with the downcoming flow annulus, and an inner shroud surge volume separated from the downcoming flow annulus by the inner shroud. When the solid particles are resting on the sludge basin and a fluid such as water is atop the particles and extending into the downcoming flow annulus and the inner shroud surge volume, mixing occurs by pressurization of the upper vessel pressurization volume, generating an inward radial flow over the flow surface and an upwash jet at the center of the sludge basin.

  8. HYDROLYZED WOOD SLURRY FLOW MODELING

    E-Print Network [OSTI]

    Wrathall, Jim

    2012-01-01

    LBL-10090 UC-61 HYDROLYZED WOOD SLURRY FLOW MODELING JimLBL-10090 HYDROLYZED WOOD SLURRY FLOW MODELING Jim Wrathallconversion of hydrolyzed wood slurry to fuel oil, Based on

  9. Structural power flow measurement

    SciTech Connect (OSTI)

    Falter, K.J.; Keltie, R.F.

    1988-12-01

    Previous investigations of structural power flow through beam-like structures resulted in some unexplained anomalies in the calculated data. In order to develop structural power flow measurement as a viable technique for machine tool design, the causes of these anomalies needed to be found. Once found, techniques for eliminating the errors could be developed. Error sources were found in the experimental apparatus itself as well as in the instrumentation. Although flexural waves are the carriers of power in the experimental apparatus, at some frequencies longitudinal waves were excited which were picked up by the accelerometers and altered power measurements. Errors were found in the phase and gain response of the sensors and amplifiers used for measurement. A transfer function correction technique was employed to compensate for these instrumentation errors.

  10. Ricci flow and quantum theory

    E-Print Network [OSTI]

    Robert Carroll

    2007-11-05

    We show some relations between Ricci flow and quantum theory via Fisher information and the quantum potential.

  11. Flow dynamics of the Moon

    E-Print Network [OSTI]

    Yu. N. Bratkov

    2010-04-03

    Flow analysis of big basins is given. Internal structure of flows is considered. Correlations between flows are calculated. For example, Mare Orientale is a moving basin. Orientale and Imbrium continental basins are introduced and are considered. Olbers ray crater is a result of precise interaction of the two basins. Flows of the Tycho type are studied. Two Antarctidae, an Indian Ocean, and an America are demonstrated.

  12. TEP process flow diagram

    SciTech Connect (OSTI)

    Wilms, R Scott; Carlson, Bryan; Coons, James; Kubic, William

    2008-01-01

    This presentation describes the development of the proposed Process Flow Diagram (PFD) for the Tokamak Exhaust Processing System (TEP) of ITER. A brief review of design efforts leading up to the PFD is followed by a description of the hydrogen-like, air-like, and waterlike processes. Two new design values are described; the mostcommon and most-demanding design values. The proposed PFD is shown to meet specifications under the most-common and mostdemanding design values.

  13. Convective heat flow probe

    DOE Patents [OSTI]

    Dunn, J.C.; Hardee, H.C.; Striker, R.P.

    1984-01-09

    A convective heat flow probe device is provided which measures heat flow and fluid flow magnitude in the formation surrounding a borehole. The probe comprises an elongate housing adapted to be lowered down into the borehole; a plurality of heaters extending along the probe for heating the formation surrounding the borehole; a plurality of temperature sensors arranged around the periphery of the probe for measuring the temperature of the surrounding formation after heating thereof by the heater elements. The temperature sensors and heater elements are mounted in a plurality of separate heater pads which are supported by the housing and which are adapted to be radially expanded into firm engagement with the walls of the borehole. The heat supplied by the heater elements and the temperatures measured by the temperature sensors are monitored and used in providing the desired measurements. The outer peripheral surfaces of the heater pads are configured as segments of a cylinder and form a full cylinder when taken together. A plurality of temperature sensors are located on each pad so as to extend along the length and across the width thereof, with a heating element being located in each pad beneath the temperature sensors. An expansion mechanism driven by a clamping motor provides expansion and retraction of the heater pads and expandable packet-type seals are provided along the probe above and below the heater pads.

  14. 1206 IEEE TRANSACTIONS ON PLASMA SCIENCE, VOL. 36, NO. 4, AUGUST 2008 Dual-Species Plasmas Illustrate MHD Flows

    E-Print Network [OSTI]

    Bellan, Paul M.

    to pinch down at the axial midpoint, decreasing the axial variation. The axial magnetic field are with the California Institute of Technology, Pasadena, CA 91125 USA (e-mail: eve@caltech.edu). Digital Object

  15. Microgravity Flow Regime Transition Modeling 

    E-Print Network [OSTI]

    Shephard, Adam M.

    2010-07-14

    Flow regime transitions and the modeling thereof underlie the design of microgravity two-phase systems. Through the use of the zero-g laboratory, microgravity two-phase flows can be studied. Because microgravity two-phase flows exhibit essentially...

  16. Flow regime mapping of vertical two-phase downflow in a ribbed annulus

    SciTech Connect (OSTI)

    Kielpinski, A.L.

    1992-01-01

    Two-phase flow regimes have been mapped for vertical, cocurrent downflow in a narrow annulus which is partially segmented by the presence of longitudinal ribs. This geometry and flow condition has application to the analysis of a Large-Break Loss of Coolant Accident (LB-LOCA) in the production K-Reactor at the Savannah River Site (SRS). The ribbed annular geometry, particularly the presence of non-sealing ribs, gives rise to some unique phenomenological features. The flow behavior is influenced by the partial segmentation of the annulus into four quadrants or subchannels. A random element is induced by the natural bowing of the slender tubes; the width of the azimuthal flow path between two subchannels at a given axial location is indeterminate, and can take on any value between zero and the maximum clearance of 7.6 [times] l0[sup [minus]4] m. When the rib gap is zero at a given location, it is at a maximum 180P away at the same axial location. The range of rib gaps is spanned in a single test section, as it would be also in a reactor assembly. As a result of these effects, flow regime maps obtained by other researchers for downflow in annuli are not accurate for defining flow regimes in a ribbed annulus. Flow regime transitions similar to those noted by, e.g., Bamea, were observed; the locations of these transitions were displaced with respect to the transition equations derived by Bamea. Experimental bubble rise velocity measurements were also obtained in the same test section. The bubble rise velocities were much higher than expected from the theory developed for slug bubbles in tubes, unribbed annuli, and rectangular channels. An elliptical-cap bubble rises faster than a slug bubble of the same area. Large, slug-shaped bubbles injected into the test section were observed to reduce in size as they rose, due to interaction with a longitudinal rib. They thereby adopted a shape more like an elliptical-cap bubble, hence rising faster than the original slug bubble.

  17. Flow regime mapping of vertical two-phase downflow in a ribbed annulus

    SciTech Connect (OSTI)

    Kielpinski, A.L.

    1992-12-01

    Two-phase flow regimes have been mapped for vertical, cocurrent downflow in a narrow annulus which is partially segmented by the presence of longitudinal ribs. This geometry and flow condition has application to the analysis of a Large-Break Loss of Coolant Accident (LB-LOCA) in the production K-Reactor at the Savannah River Site (SRS). The ribbed annular geometry, particularly the presence of non-sealing ribs, gives rise to some unique phenomenological features. The flow behavior is influenced by the partial segmentation of the annulus into four quadrants or subchannels. A random element is induced by the natural bowing of the slender tubes; the width of the azimuthal flow path between two subchannels at a given axial location is indeterminate, and can take on any value between zero and the maximum clearance of 7.6 {times} l0{sup {minus}4} m. When the rib gap is zero at a given location, it is at a maximum 180P away at the same axial location. The range of rib gaps is spanned in a single test section, as it would be also in a reactor assembly. As a result of these effects, flow regime maps obtained by other researchers for downflow in annuli are not accurate for defining flow regimes in a ribbed annulus. Flow regime transitions similar to those noted by, e.g., Bamea, were observed; the locations of these transitions were displaced with respect to the transition equations derived by Bamea. Experimental bubble rise velocity measurements were also obtained in the same test section. The bubble rise velocities were much higher than expected from the theory developed for slug bubbles in tubes, unribbed annuli, and rectangular channels. An elliptical-cap bubble rises faster than a slug bubble of the same area. Large, slug-shaped bubbles injected into the test section were observed to reduce in size as they rose, due to interaction with a longitudinal rib. They thereby adopted a shape more like an elliptical-cap bubble, hence rising faster than the original slug bubble.

  18. MERTOL, HALIT CENAN. Behavior of High-Strength Concrete Members Subjected to Combined Flexure and Axial Compression Loadings. (Under the direction of Dr. Sami

    E-Print Network [OSTI]

    Flexure and Axial Compression Loadings. (Under the direction of Dr. Sami Rizkalla.) The use of high in 1999 in Middle East Technical University, Ankara, Turkey. He also received his Master of Science degree of the National Research Council who administered National C

  19. GaAs nanowire array solar cells with axial p-i-n Maoqing Yao, Ningfeng Huang, Sen Cong, Chun-Yung Chi, M. Ashkan Seyedi,

    E-Print Network [OSTI]

    Zhou, Chongwu

    interconnecting scheme. Figure S1. Multi-junction solar cells. (a) Multi-junction solar cells consist of materials1 GaAs nanowire array solar cells with axial p-i-n junctions Maoqing Yao, Ningfeng Huang, Sen CongH3 are 7.56×10-7 atm and 2.14×10-4 atm. Solar cells fabrication. Transparent insulating polymer BCB

  20. Nuclear Instruments and Methods in Physics Research A 547 (2005) 663678 Determining axial fuel-rod power-density profiles from in-core

    E-Print Network [OSTI]

    Shultis, J. Kenneth

    2005-01-01

    is proposed for determining power-density profiles in nuclear reactor fuel rods from neutron flux measurementsNuclear Instruments and Methods in Physics Research A 547 (2005) 663­678 Determining axial fuel-rod power-density profiles from in-core neutron flux measurements J. Kenneth Shultisà Department

  1. MULTILAYER CERAMIC CAPACITORS/AXIAL & RADIAL LEADED KEMET Electronics Corporation, P.O. Box 5928, Greenville, S.C. 29606, (864) 963-6300

    E-Print Network [OSTI]

    Berns, Hans-Gerd

    MULTILAYER CERAMIC CAPACITORS/AXIAL & RADIAL LEADED KEMET Electronics Corporation, P.O. Box 5928, Greenville, S.C. 29606, (864) 963-6300 KEMET ® Multilayer ceramic capacitors are available in a variety materials and methods vary depending on the intended use. TEMPERATURE CHARACTERISTICS Ceramic dielectric

  2. Modified helix-like instability structure on imploding z-pinch liners that are pre-imposed with a uniform axial magnetic field

    SciTech Connect (OSTI)

    Awe, T. J., E-mail: tjawe@sandia.gov; Jennings, C. A.; McBride, R. D.; Cuneo, M. E.; Lamppa, D. C.; Martin, M. R.; Rovang, D. C.; Sinars, D. B.; Slutz, S. A.; Owen, A. C.; Gomez, M. R.; Hansen, S. B.; Herrmann, M. C.; Jones, M. C.; McKenney, J. L.; Robertson, G. K.; Rochau, G. A.; Savage, M. E.; Stygar, W. A. [Sandia National Laboratories, P.O. Box 5800, Albuquerque, New Mexico 87185 (United States)] [Sandia National Laboratories, P.O. Box 5800, Albuquerque, New Mexico 87185 (United States); Tomlinson, K. [General Atomics, San Diego, California 92121 (United States)] [General Atomics, San Diego, California 92121 (United States); and others

    2014-05-15

    Recent experiments at the Sandia National Laboratories Z Facility have, for the first time, studied the implosion dynamics of magnetized liner inertial fusion (MagLIF) style liners that were pre-imposed with a uniform axial magnetic field. As reported [T. J. Awe et al., Phys. Rev. Lett. 111, 235005 (2013)] when premagnetized with a 7 or 10?T axial field, these liners developed 3D-helix-like hydrodynamic instabilities; such instabilities starkly contrast with the azimuthally correlated magneto-Rayleigh-Taylor (MRT) instabilities that have been consistently observed in many earlier non-premagnetized experiments. The helical structure persisted throughout the implosion, even though the azimuthal drive field greatly exceeded the expected axial field at the liner's outer wall for all but the earliest stages of the experiment. Whether this modified instability structure has practical importance for magneto-inertial fusion concepts depends primarily on whether the modified instability structure is more stable than standard azimuthally correlated MRT instabilities. In this manuscript, we discuss the evolution of the helix-like instability observed on premagnetized liners. While a first principles explanation of this observation remains elusive, recent 3D simulations suggest that if a small amplitude helical perturbation can be seeded on the liner's outer surface, no further influence from the axial field is required for the instability to grow.

  3. PWR FLECHT SEASET 21-rod-bundle flow-blockage task: data and analysis report. NRC/EPRI/Westinghouse report No. 11, main report and appendices A-J

    SciTech Connect (OSTI)

    Loftus, M.J.; Hochreiter, L.E.; Lee, N.; McGuire, M.F.; Wenzel, A.H.; Valkovic, M.M.

    1982-09-01

    This report presents data and limited analysis from the 21-Rod Bundle Flow Blockage Task of the Full-Length Emergency Cooling Heat Transfer Separate Effects and Systems Effects Test Program (FLECHT SEASET). The tests consisted of forced and gravity reflooding tests utilizing electrical heater rods with a cosine axial power profile to simulate PWR nuclear core fuel rod arrays. Steam cooling and hydraulic characteristics tests were also conducted. These tests were utilized to determine effects of various flow blockage configurations (shapes and distributions) on reflooding behavior, to aid in development/assessment of computational models in predicting reflooding behavior of flow blockage configurations, and to screen flow blockage configurations for future 163-rod flow blockage bundle tests.

  4. Temperature, humidity and air flow in the emplacement drifts using convection and dispersion transport models

    SciTech Connect (OSTI)

    Danko, G.; Birkholzer, J.T.; Bahrami, D.; Halecky, N.

    2009-10-01

    A coupled thermal-hydrologic-airflow model is developed, solving for the transport processes within a waste emplacement drift and the surrounding rockmass together at the proposed nuclear waste repository at Yucca Mountain. Natural, convective air flow as well as heat and mass transport in a representative emplacement drift during post-closure are explicitly simulated, using the MULTIFLUX model. The conjugate, thermal-hydrologic transport processes in the rockmass are solved with the TOUGH2 porous-media simulator in a coupled way to the in-drift processes. The new simulation results show that large-eddy turbulent flow, as opposed to small-eddy flow, dominate the drift air space for at least 5000 years following waste emplacement. The size of the largest, longitudinal eddy is equal to half of the drift length, providing a strong axial heat and moisture transport mechanism from the hot to the cold drift sections. The in-drift results are compared to those from simplified models using a surrogate, dispersive model with an equivalent dispersion coefficient for heat and moisture transport. Results from the explicit, convective velocity simulation model provide higher axial heat and moisture fluxes than those estimated from the previously published, simpler, equivalent-dispersion models, in addition to showing differences in temperature, humidity and condensation rate distributions along the drift length. A new dispersive model is also formulated, giving a time- and location-variable function that runs generally about ten times higher in value than the highest dispersion coefficient currently used in the Yucca Mountain Project as an estimate for the equivalent dispersion coefficient in the emplacement drift. The new dispersion coefficient variation, back-calculated from the convective model, can adequately describe the heat and mass transport processes in the emplacement drift example.

  5. Water Power for a Clean Energy Future (Fact Sheet)

    SciTech Connect (OSTI)

    Not Available

    2010-07-01

    Water power technologies harness energy from rivers and oceans to generate electricity for the nation's homes and businesses, and can help the United States meet its pressing energy, environmental, and economic challenges. Water power technologies; fall into two broad categories: conventional hydropower and marine and hydrokinetic technologies. Conventional hydropower uses dams or impoundments to store river water in a reservoir. Marine and hydrokinetic technologies capture energy from waves, tides, ocean currents, free-flowing rivers, streams, and ocean thermal gradients.

  6. Flow Battery Technology

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

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Homesum_a_epg0_fpd_mmcf_m.xls" ,"Available from WebQuantity ofkandz-cm11 Outreach Home Room NewsInformation Current HABFES OctoberEvanServices »First ObservationFast(ER1)Flow Battery

  7. Fast wire-mesh sensors for gas-liquid flows - Visualisation with up to 10 000 frames per second

    SciTech Connect (OSTI)

    Prasser, H.M.; Zschau, J. [Forschungszentrum Rossendorf e.V., P.O.Box 510119, D-01314 Dresden (Germany); Peters, D.; Pietzsch, G.; Taubert, W.; Trepte, M. [Teletronic Ingenieurbuero GmbH, Bautzner Landstrasse 45, D-01454 Grosserkmannsdorf (Germany)

    2002-07-01

    A wire-mesh sensor developed by the Forschungszentrum Rossendorf produces sequences of instantaneous gas fraction distributions in a cross section at a rate of up to 10 000 frames per second and a spatial resolution of about 2-3 mm. This sensor was applied to an upwards air-liquid flow in a vertical pipe of 51.2 mm diameter. After a brief introduction of the functioning of the sensor, the paper presents results obtained in a at vertical pipe operated with an air-water mixture. Two wire-mesh sensors with a measuring matrix of 24 x 24 points (resolution 2 mm) were placed in a small axial distance behind each other. They were used to study the flow structure in the transition region from bubble to slug flow at an imaging frequency of 2 500 Hz. The two available measuring planes allowed to obtain velocity profiles of the gaseous phase. A sensor with 16 x 16 points (resolution 3 mm) was applied to visualize the transition from bubbly via churn turbulent to annular flow with 10 000 frames per second. In the churn flow region, periodic plug-like structures were found. In the annular flow the sensor is able to resolve wispy structures. (authors)

  8. Spiral Laminar Flow: A revolution in understanding?

    E-Print Network [OSTI]

    Greenaway, Alan

    Blood Flow Spiral laminar flow #12;Spiral flow in the Aorta (MRI) Computational Fluid Dynamics 0 10 20Spiral Laminar Flow: A revolution in understanding? Reintroduction of natural blood flow Laminar Flow through Runoff (3months) Proximal Anastomosis SLF TM Graft Distal Anastomosis Post-op Angios

  9. Radial flow heat exchanger

    DOE Patents [OSTI]

    Valenzuela, Javier (Hanover, NH)

    2001-01-01

    A radial flow heat exchanger (20) having a plurality of first passages (24) for transporting a first fluid (25) and a plurality of second passages (26) for transporting a second fluid (27). The first and second passages are arranged in stacked, alternating relationship, are separated from one another by relatively thin plates (30) and (32), and surround a central axis (22). The thickness of the first and second passages are selected so that the first and second fluids, respectively, are transported with laminar flow through the passages. To enhance thermal energy transfer between first and second passages, the latter are arranged so each first passage is in thermal communication with an associated second passage along substantially its entire length, and vice versa with respect to the second passages. The heat exchangers may be stacked to achieve a modular heat exchange assembly (300). Certain heat exchangers in the assembly may be designed slightly differently than other heat exchangers to address changes in fluid properties during transport through the heat exchanger, so as to enhance overall thermal effectiveness of the assembly.

  10. Active combustion flow modulation valve

    DOE Patents [OSTI]

    Hensel, John Peter; Black, Nathaniel; Thorton, Jimmy Dean; Vipperman, Jeffrey Stuart; Lambeth, David N; Clark, William W

    2013-09-24

    A flow modulation valve has a slidably translating hollow armature with at least one energizable coil wound around and fixably attached to the hollow armature. The energizable coil or coils are influenced by at least one permanent magnet surrounding the hollow armature and supported by an outer casing. Lorentz forces on the energizable coils which are translated to the hollow armature, increase or decrease the flow area to provide flow throttling action. The extent of hollow armature translation depends on the value of current supplied and the direction of translation depends on the direction of current flow. The compact nature of the flow modulation valve combined with the high forces afforded by the actuator design provide a flow modulation valve which is highly responsive to high-rate input control signals.

  11. Drains Debubbler Transport Liq. Flow

    E-Print Network [OSTI]

    Weber, Rodney

    Drains Debubbler Transport Liq. Flow (LiF) aq. Anion Cation Waste Vacuum Pump LiF H2 O Pure H2 O 1 Denuders Cyclon 16 L/min 2.5 µm cut Sample Tubing ColourFlow, mL/minTubing green/green-1 green/green-2, and Liquid Flow Rates Are Possible Cation: metrosep 2100B-100x4.0mm Eluent: 0.250g/L Dipicolinic acid 1000 u

  12. Magneto-Centrifugal Launching of Jets from Accretion Disks; 1, Cold Axisymmetric Flows

    E-Print Network [OSTI]

    Krasnopolsky, R; Blandford, R D

    1999-01-01

    The magneto-centrifugal model for jet formation is studied by time-dependent simulations reaching steady state in a cold gas with negligible fluid pressure, in an axisymmetric geometry, using a modification of the Zeus3D code adapted to parallel computers. The number of boundary conditions imposed at the coronal base takes into account the existence of the fast and Alfvenic critical surfaces, avoiding over-determination of the flow. The size and shape of the computational box is chosen to include these critical surfaces, reducing the influence of the outer boundary conditions. As there is a region, near the origin, where the inclination of field lines to the axis is too small to drive a centrifugal wind, we inject a thin, axial jet, expected to form electromagnetically near black holes. Acceleration and collimation appear for wide generic conditions. A reference run is shown in detail, with a wind leaving the computational volume in the axial direction with a poloidal velocity equal to 4 times the poloidal Al...

  13. Magneto-Centrifugal Launching of Jets from Accretion Disks. I: Cold Axisymmetric Flows

    E-Print Network [OSTI]

    R. Krasnopolsky; Z. -Y. Li; R. D. Blandford

    1999-07-29

    The magneto-centrifugal model for jet formation is studied by time-dependent simulations reaching steady state in a cold gas with negligible fluid pressure, in an axisymmetric geometry, using a modification of the Zeus3D code adapted to parallel computers. The number of boundary conditions imposed at the coronal base takes into account the existence of the fast and Alfvenic critical surfaces, avoiding over-determination of the flow. The size and shape of the computational box is chosen to include these critical surfaces, reducing the influence of the outer boundary conditions. As there is a region, near the origin, where the inclination of field lines to the axis is too small to drive a centrifugal wind, we inject a thin, axial jet, expected to form electromagnetically near black holes. Acceleration and collimation appear for wide generic conditions. A reference run is shown in detail, with a wind leaving the computational volume in the axial direction with a poloidal velocity equal to 4 times the poloidal Alfven speed, collimated inside 11 degrees. Finally, the critical surfaces, fieldlines, thrust, energy, torque and mass discharge of the outgoing wind are shown for simulations with various profiles of mass and magnetic flux at the base of the corona.

  14. Elliptic Flow at Large Viscosity

    E-Print Network [OSTI]

    Volker Koch

    2009-09-18

    In this contribution we present an alternative scenario for the large elliptic flow observed in relativistic heavy ion collisions. Motivated by recent results from Lattice QCD on flavor off-diagonal susceptibilities we argue that the matter right above $T_{c}$ can be described by single-particle dynamics in a repulsive single-particle potential, which in turn gives rise to elliptic flow. These ideas can be tested experimentally by measuring elliptic flow of heavy quarks, preferably via the measurement of $J/\\Psi$ elliptic flow.

  15. Module bay with directed flow

    SciTech Connect (OSTI)

    Torczynski, John R. (Albuquerque, NM)

    2001-02-27

    A module bay requires less cleanroom airflow. A shaped gas inlet passage can allow cleanroom air into the module bay with flow velocity preferentially directed toward contaminant rich portions of a processing module in the module bay. Preferential gas flow direction can more efficiently purge contaminants from appropriate portions of the module bay, allowing a reduced cleanroom air flow rate for contaminant removal. A shelf extending from an air inlet slit in one wall of a module bay can direct air flowing therethrough toward contaminant-rich portions of the module bay, such as a junction between a lid and base of a processing module.

  16. Kauai Groundwater Flow Model

    DOE Data Explorer [Office of Scientific and Technical Information (OSTI)]

    Nicole Lautze

    2015-01-01

    Groundwater flow model for Kauai. Data is from the following sources: Whittier, R. and A.I. El-Kadi. 2014. Human and Environmental Risk Ranking of Onsite Sewage Disposal Systems For the Hawaiian Islands of Kauai, Molokai, Maui, and Hawaii – Final. Prepared by the University of Hawaii, Dept. of Geology and Geophysics for the State of Hawaii Dept. of Health, Safe Drinking Water Branch. September 2014.; and Whittier, R.B., K. Rotzoll, S. Dhal, A.I. El-Kadi, C. Ray, G. Chen, and D. Chang. 2004. Hawaii Source Water Assessment Program Report – Volume IV – Island of Kauai Source Water Assessment Program Report. Prepared for the Hawaii Department of Health, Safe Drinking Water Branch. University of Hawaii, Water Resources Research Center. Updated 2015.

  17. The influence of current collectors on Tayler instability and electro-vortex flows in liquid metal batteries

    E-Print Network [OSTI]

    Weber, N; Priede, J; Stefani, F; Weier, T

    2014-01-01

    The Tayler instability is a kink-type flow instability which occurs when the electrical current through a conducting fluid exceeds a certain critical value. Originally studied in the astrophysical context, the instability was recently shown to be also a limiting factor for the upward scalability of liquid metal batteries. In this paper, we continue our efforts to simulate this instability for liquid metals within the framework of an integro-differential equation approach. The original solver is enhanced by multi-domain support with Dirichlet-Neumann partitioning for the static boundaries. Particular focus is laid on the detailed influence of the axial electrical boundary conditions on the characteristic features of the Tayler instability, and, secondly, on the occurrence of electro-vortex flows and their relevance for liquid metal batteries.

  18. Non--Atomic Components of Data Flow Diagrams: Stores, Persistent Flows,

    E-Print Network [OSTI]

    Symanzik, Jürgen

    Non--Atomic Components of Data Flow Diagrams: Stores, Persistent Flows, and Tests for Empty Flows J NON--ATOMIC COMPONENTS OF DATA FLOW DIAGRAMS: STORES, PERSISTENT FLOWS, AND TESTS FOR EMPTY FLOWS of these common features of traditional Data Flow Diagrams elevates the expressive power of FDFD's, or whether

  19. Marine and Hydrokinetic (MHK) Technology Development Risk Management...

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

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  20. Marine and Hydrokinetic (MHK) Technology Development Risk Management...

    Office of Environmental Management (EM)

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