National Library of Energy BETA

Sample records for turbulent nuclear combustion

  1. Turbulent combustion

    SciTech Connect (OSTI)

    Talbot, L.; Cheng, R.K. [Lawrence Berkeley Laboratory, CA (United States)

    1993-12-01

    Turbulent combustion is the dominant process in heat and power generating systems. Its most significant aspect is to enhance the burning rate and volumetric power density. Turbulent mixing, however, also influences the chemical rates and has a direct effect on the formation of pollutants, flame ignition and extinction. Therefore, research and development of modern combustion systems for power generation, waste incineration and material synthesis must rely on a fundamental understanding of the physical effect of turbulence on combustion to develop theoretical models that can be used as design tools. The overall objective of this program is to investigate, primarily experimentally, the interaction and coupling between turbulence and combustion. These processes are complex and are characterized by scalar and velocity fluctuations with time and length scales spanning several orders of magnitude. They are also influenced by the so-called {open_quotes}field{close_quotes} effects associated with the characteristics of the flow and burner geometries. The authors` approach is to gain a fundamental understanding by investigating idealized laboratory flames. Laboratory flames are amenable to detailed interrogation by laser diagnostics and their flow geometries are chosen to simplify numerical modeling and simulations and to facilitate comparison between experiments and theory.

  2. Sandia Energy - Turbulent Combustion

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

    Combustion Home Transportation Energy Predictive Simulation of Engines Reacting Flow Experiments Turbulent Combustion Turbulent CombustionAshley Otero2015-10-30T01:39:47+00...

  3. Simulation of lean premixed turbulent combustion

    E-Print Network [OSTI]

    2008-01-01

    turbulent methane combustion. Proc. Combust. Inst. , 29:in premixed turbulent combustion. Proc. Combust. Inst. ,for zero Mach number combustion. Combust. Sci. Technol. ,

  4. Four Lectures on Turbulent Combustion

    E-Print Network [OSTI]

    Peters, Norbert

    Four Lectures on Turbulent Combustion N. Peters Institut f¨ur Technische Mechanik RWTH Aachen Turbulent Combustion: Introduction and Overview 1 1.1 Moment Methods in Modeling Turbulence with Combustion and Velocity Scales . . . . . . . . . . . 11 1.4 Regimes in Premixed Turbulent Combustion

  5. Sandia Energy - Applied Turbulent Combustion

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

    and they form the basis for the creation of validated submodels that bridge fundamental energy sciences with applied device engineering and optimization. Turbulent-combustion-lab...

  6. Assessment of Combustion and Turbulence Models for the Simulation...

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

    Combustion and Turbulence Models for the Simulation of Combustion Processes in a DI Diesel Engine Assessment of Combustion and Turbulence Models for the Simulation of Combustion...

  7. Fifteen Lectures on Laminar and Turbulent Combustion

    E-Print Network [OSTI]

    Peters, Norbert

    Fifteen Lectures on Laminar and Turbulent Combustion N. Peters RWTH Aachen Ercoftac Summer School in Combustion Systems 1 Lecture 2: Calculation of Adiabatic Flame Temperatures and Chemical Equilibria 20: Laminar Diffusion Flames: Different Flow Geometries 156 Lecture 11: Turbulent Combustion: Introduction

  8. Sandia Energy - Applied Turbulent Combustion

    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 RoomPreservation of Fe(II) byMultidayAlumni >ScientificApplied Turbulent Combustion Home

  9. Reaction and diffusion in turbulent combustion

    SciTech Connect (OSTI)

    Pope, S.B. [Mechanical and Aerospace Engineering, Ithaca, NY (United States)

    1993-12-01

    The motivation for this project is the need to obtain a better quantitative understanding of the technologically-important phenomenon of turbulent combustion. In nearly all applications in which fuel is burned-for example, fossil-fuel power plants, furnaces, gas-turbines and internal-combustion engines-the combustion takes place in a turbulent flow. Designers continually demand more quantitative information about this phenomenon-in the form of turbulent combustion models-so that they can design equipment with increased efficiency and decreased environmental impact. For some time the PI has been developing a class of turbulent combustion models known as PDF methods. These methods have the important virtue that both convection and reaction can be treated without turbulence-modelling assumptions. However, a mixing model is required to account for the effects of molecular diffusion. Currently, the available mixing models are known to have some significant defects. The major motivation of the project is to seek a better understanding of molecular diffusion in turbulent reactive flows, and hence to develop a better mixing model.

  10. NUMERICAL MODELING OF TURBULENT FLOW IN A COMBUSTION TUNNEL

    E-Print Network [OSTI]

    Ghoniem, A.F.

    2013-01-01

    of turbulent combustion in a 1 ean propane~a1 of high sp r mturbulent combustion stabilized behind a step in a propane~combustion behind a step at R while Su corresponding to a propane-

  11. NUMERICAL MODELING OF TURBULENT FLOW IN A COMBUSTION TUNNEL

    E-Print Network [OSTI]

    Ghoniem, A.F.

    2013-01-01

    1VJcDona·ld, H. (1979) Combustion r 1 iodeJ·ing in Two and1979) Practical Turbulent-Combustion Interaction Models forInternation on Combustors. Combustion The 17th Symposium

  12. Turbulent Combustion in SDF Explosions

    SciTech Connect (OSTI)

    Kuhl, A L; Bell, J B; Beckner, V E

    2009-11-12

    A heterogeneous continuum model is proposed to describe the dispersion and combustion of an aluminum particle cloud in an explosion. It combines the gas-dynamic conservation laws for the gas phase with a continuum model for the dispersed phase, as formulated by Nigmatulin. Inter-phase mass, momentum and energy exchange are prescribed by phenomenological models. It incorporates a combustion model based on the mass conservation laws for fuel, air and products; source/sink terms are treated in the fast-chemistry limit appropriate for such gasdynamic fields, along with a model for mass transfer from the particle phase to the gas. The model takes into account both the afterburning of the detonation products of the C-4 booster with air, and the combustion of the Al particles with air. The model equations were integrated by high-order Godunov schemes for both the gas and particle phases. Numerical simulations of the explosion fields from 1.5-g Shock-Dispersed-Fuel (SDF) charge in a 6.6 liter calorimeter were used to validate the combustion model. Then the model was applied to 10-kg Al-SDF explosions in a an unconfined height-of-burst explosion. Computed pressure histories are compared with measured waveforms. Differences are caused by physical-chemical kinetic effects of particle combustion which induce ignition delays in the initial reactive blast wave and quenching of reactions at late times. Current simulations give initial insights into such modeling issues.

  13. A Model for Turbulent Combustion Simulation of Large Scale Hydrogen...

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

    A Model for Turbulent Combustion Simulation of Large Scale Hydrogen Explosions Event Sponsor: Argonne Leadership Computing Facility Seminar Start Date: Oct 6 2015 - 10:00am...

  14. Sandia Energy - Turbulent Mixed-Mode Combustion Studied in a...

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

    Turbulent Mixed-Mode Combustion Studied in a New Piloted Burner Home Transportation Energy CRF Office of Science Capabilities News News & Events Research & Capabilities Fuel...

  15. Sandia Energy - The CRF's Turbulent Combustion Lab (TCL) Captures...

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

    CRF's Turbulent Combustion Lab (TCL) Captures the Moment of Hydrogen Ignition Home Energy Transportation Energy CRF Facilities News News & Events Research & Capabilities The CRF's...

  16. Flame Surface Fractal Characteristics in Premixed Turbulent Combustion at High Turbulence Intensities

    E-Print Network [OSTI]

    Gülder, Ömer L.

    Flame Surface Fractal Characteristics in Premixed Turbulent Combustion at High Turbulence of the flame surfaces in premixed turbulent combustion, the fractal approach is considered to be one with diameters of 11.2 and 22.4 mm, with flames of propane­air with equivalence ratios of 0.8 and 1

  17. A Topological Framework for the Interactive Exploration of Large Scale Turbulent Combustion

    E-Print Network [OSTI]

    Bremer, Peer-Timo

    2010-01-01

    comparison of terascale combustion simulation data. Mathe-premixed hydrogen ?ames. Combustion and Flame, [7] J. L.of Large Scale Turbulent Combustion Peer-Timo Bremer 1 ,

  18. Assessment of Combustion and Turbulence Models for the Simulation of Combustion Processes in a DI Diesel Engine

    Broader source: Energy.gov [DOE]

    Various applied combustion and turbulence models were investigated along with chemical kinetic mechanisms simulating a biodiesel-fueled engine

  19. 3 - 4 Turbulent combustion Princeton.key

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

    speed (s T ) Turbulent RMS velocity in the fresh gas (u') Low turbulence zone s T a u' Bending zone Quenching l i m i t s L 0 Problem: these functions are configuration...

  20. Advanced Computational Methods for Turbulence and Combustion...

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

    of premixed lean fuels for clean, efficient combustion devices such as low-swirl burners. Over 80% of energy consumed in the U.S. occurs via the burning of fossil fuels in...

  1. LES Simulations of Turbulent Combustion in a Type Ia Supernovae

    E-Print Network [OSTI]

    New York at Stoney Brook, State University of

    to be thermonuclear explosions of white dwarfs. SNIa are important sources of energy and chemical elements deposited of the burning are all determined by the speed of thermonuclear burning [27]. The problem of turbulent combustionE= _ S. Here #21; is the electron mean free path, E is a characteristic energy per unit mass, c

  2. Paper # B03 Topic: Turbulent Flames US Combustion Meeting

    E-Print Network [OSTI]

    Pitsch, Heinz

    a crucial role in transferring chemical energy stored in fossil fuels into heat. It has been estimatedPaper # B03 Topic: Turbulent Flames 5th US Combustion Meeting Organized by the Western States subfilter model, which is designed for inhomogeneous flow in complex configurations, is employed. Laminar

  3. Combustion-turbulence interaction in the turbulent boundary layer over a hot surface

    SciTech Connect (OSTI)

    Ng, T.T.; Cheng, R.K.; Robben, F.; Talbot, L.

    1982-01-01

    The turbulence-combustion interaction in a reacting turbulent boundary layer over a heated flat plate was studied. Ethylene/air mixture with equivalence ratio of 0.35 was used. The free stream velocity was 10.5 m/s and the wall temperature was 1250/sup 0/K. Combustion structures visualization was provided by high-speed schlieren photographs. Fluid density statistics were deduced from Rayleigh scattering intensity measurements. A single-component laser Doppler velocimetry system was used to obtain mean and root-mean-square velocity distributions, the Reynolds stress, the streamwise and the cross-stream turbulent kinetic energy diffusion, and the production of turbulent kinetic energy by Reynolds stress. The combustion process was dominated by large-scale turbulent structures of the boundary layer. Combustion causes expansion of the boundary layer. No overall self-similarity is observed in either the velocity or the density profiles. Velocity fluctuations were increased in part of the boundary layer and the Reynolds stress was reduced. The turbulent kinetic energy diffusion pattern was changed significantly and a modification of the boundary layer assumption will be needed when dealing with this problem analytically. 11 figures, 1 table.

  4. A spray-suppression model for turbulent combustion

    SciTech Connect (OSTI)

    DESJARDIN,PAUL E.; TIESZEN,SHELDON R.; GRITZO,LOUIS A.

    2000-02-14

    A spray-suppression model that captures the effects of liquid suppressant on a turbulent combusting flow is developed and applied to a turbulent diffusion flame with water spray suppression. The spray submodel is based on a stochastic separated flow approach that accounts for the transport and evaporation of liquid droplets. Flame extinguishment is accounted for by using a perfectly stirred reactor (PSR) submodel of turbulent combustion. PSR pre-calculations of flame extinction times are determined using CHEMKIN and are compared to local turbulent time scales of the flow to determine if local flame extinguishment has occurred. The PSR flame extinguishment and spray submodels are incorporated into Sandia's flow fire simulation code, VULCAN, and cases are run for the water spray suppression studies of McCaffrey for turbulent hydrogen-air jet diffusion flames. Predictions of flame temperature decrease and suppression efficiency are compared to experimental data as a function of water mass loading using three assumed values of drop sizes. The results show that the suppression efficiency is highly dependent on the initial droplet size for a given mass loading. A predicted optimal suppression efficiency was observed for the smallest class of droplets while the larger drops show increasing suppression efficiency with increasing mass loading for the range of mass loadings considered. Qualitative agreement to the experiment of suppression efficiency is encouraging, however quantitative agreement is limited due to the uncertainties in the boundary conditions of the experimental data for the water spray.

  5. Gasdynamic Model of Turbulent Combustion in TNT Explosions

    SciTech Connect (OSTI)

    Kuhl, A L; Bell, J B; Beckner, V E

    2010-01-08

    A model is proposed to simulate turbulent combustion in confined TNT explosions. It is based on: (i) the multi-component gasdynamic conservation laws, (ii) a fast-chemistry model for TNT-air combustion, (iii) a thermodynamic model for frozen reactants and equilibrium products, (iv) a high-order Godunov scheme providing a non-diffusive solution of the governing equations, and (v) an ILES approach whereby adaptive mesh refinement is used to capture the energy bearing scales of the turbulence on the grid. Three-dimensional numerical simulations of explosion fields from 1.5-g PETN/TNT charges were performed. Explosions in six different chambers were studied: three calorimeters (volumes of 6.6-l, 21.2-l and 40.5-l with L/D = 1), and three tunnels (L/D = 3.8, 4.65 and 12.5 with volumes of 6.3-l) - to investigate the influence of chamber volume and geometry on the combustion process. Predicted pressures histories were quite similar to measured pressure histories for all cases studied. Experimentally, mass fraction of products, Y{sub p}{sup exp}, reached a peak value of 88% at an excess air ratio of twice stoichiometric, and then decayed with increasing air dilution; mass fractions Y{sub p}{sup calc} computed from the numerical simulations followed similar trends. Based on this agreement, we conclude that the dominant effect that controls the rate of TNT combustion with air is the turbulent mixing rate; the ILES approach along with the fast-chemistry model used here adequately captures this effect.

  6. Flow, Turbulence and Combustion 71: 333346, 2003. 2004 Kluwer Academic Publishers. Printed in the Netherlands.

    E-Print Network [OSTI]

    Daraio, Chiara

    Flow, Turbulence and Combustion 71: 333­346, 2003. © 2004 Kluwer Academic Publishers. Printed of Technology, CH-8092 Zurich, Switzerland 2CFD Research Corporation, Biomedical Technology Branch, Huntsville

  7. SYMPOSIUM ON TURBULENCE AND COMBUSTION - SPECIAL SYMPOSIUM TO BRING TOGETHER TOP RESEARCHERS IN THE FIELDS OF FLUID TURBULENCE AND COMBUSTION TO PROMOTE ADVANCES IN TURBULENT, REACTING FLOWS

    SciTech Connect (OSTI)

    Caughey, David

    2010-10-08

    A Symposium on Turbulence and Combustion was held at Cornell University on August 3-4, 2009. The overall goal of the Symposium was to promote future advances in the study of turbulence and combustion, through an unique forum intended to foster interactions between leading members of these two research communities. The Symposium program consisted of twelve invited lectures given by world-class experts in these fields, two poster sessions consisting of nearly 50 presentations, an open forum, and other informal activities designed to foster discussion. Topics covered in the lectures included turbulent dispersion, wall-bounded flows, mixing, finite-rate chemistry, and others, using experiment, modeling, and computations, and included perspectives from an international community of leading researchers from academia, national laboratories, and industry.

  8. PHYSICS OF FLUIDS 25, 055107 (2013) Turbulent premixed combustion in V-shaped flames

    E-Print Network [OSTI]

    Gülder, Ömer L.

    2013-01-01

    industrial combustion systems such as, stationary gas turbines, lean premixed and prevaporized jet engines for simulating combustion in gas turbine engines. Second, although a large body of research has been devotedPHYSICS OF FLUIDS 25, 055107 (2013) Turbulent premixed combustion in V-shaped flames

  9. Subfilter Scale Modelling for Large Eddy Simulation of Lean Hydrogen-Enriched Turbulent Premixed Combustion

    E-Print Network [OSTI]

    Groth, Clinton P. T.

    Combustion by Francisco Emanuel Hernández Pérez A thesis submitted in conformity with the requirements for Large Eddy Simulation of Lean Hydrogen-Enriched Turbulent Premixed Combustion Francisco Emanuel hydrogen combustion. In recent decades, large-eddy simulation (LES) has emerged as a promising tool

  10. Terascale High-Fidelity Simulations of Turbulent Combustion with Detailed Chemistry

    SciTech Connect (OSTI)

    Im, Hong G [University of Michigan] [University of Michigan; Trouve, Arnaud [University of Maryland] [University of Maryland; Rutland, Christopher J [University of Wisconsin] [University of Wisconsin; Chen, Jacqueline H [Sandia National Laboratories] [Sandia National Laboratories

    2012-08-13

    The TSTC project is a multi-university collaborative effort to develop a high-fidelity turbulent reacting flow simulation capability utilizing terascale, massively parallel computer technology. The main paradigm of our approach is direct numerical simulation (DNS) featuring highest temporal and spatial accuracy, allowing quantitative observations of the fine-scale physics found in turbulent reacting flows as well as providing a useful tool for development of sub-models needed in device-level simulations. The code named S3D, developed and shared with Chen and coworkers at Sandia National Laboratories, has been enhanced with new numerical algorithms and physical models to provide predictive capabilities for spray dynamics, combustion, and pollutant formation processes in turbulent combustion. Major accomplishments include improved characteristic boundary conditions, fundamental studies of auto-ignition in turbulent stratified reactant mixtures, flame-wall interaction, and turbulent flame extinction by water spray. The overarching scientific issue in our recent investigations is to characterize criticality phenomena (ignition/extinction) in turbulent combustion, thereby developing unified criteria to identify ignition and extinction conditions. The computational development under TSTC has enabled the recent large-scale 3D turbulent combustion simulations conducted at Sandia National Laboratories.

  11. Terascale High-Fidelity Simulations of Turbulent Combustion with Detailed Chemistry

    SciTech Connect (OSTI)

    Hong G. Im; Arnaud Trouve; Christopher J. Rutland; Jacqueline H. Chen

    2009-02-02

    The TSTC project is a multi-university collaborative effort to develop a high-fidelity turbulent reacting flow simulation capability utilizing terascale, massively parallel computer technology. The main paradigm of our approach is direct numerical simulation (DNS) featuring highest temporal and spatial accuracy, allowing quantitative observations of the fine-scale physics found in turbulent reacting flows as well as providing a useful tool for development of sub-models needed in device-level simulations. The code named S3D, developed and shared with Chen and coworkers at Sandia National Laboratories, has been enhanced with new numerical algorithms and physical models to provide predictive capabilities for spray dynamics, combustion, and pollutant formation processes in turbulent combustion. Major accomplishments include improved characteristic boundary conditions, fundamental studies of auto-ignition in turbulent stratified reactant mixtures, flame-wall interaction, and turbulent flame extinction by water spray. The overarching scientific issue in our recent investigations is to characterize criticality phenomena (ignition/extinction) in turbulent combustion, thereby developing unified criteria to identify ignition and extinction conditions. The computational development under TSTC has enabled the recent large-scale 3D turbulent combustion simulations conducted at Sandia National Laboratories.

  12. Evaluation of a hybrid kinetics/mixing-controlled combustion model for turbulent premixed and diffusion combustion using KIVA-2

    SciTech Connect (OSTI)

    Nguyen, H.L.; Wey, Mingjyh.

    1990-01-01

    Two dimensional calculations were made of spark ignited premixed-charge combustion and direct injection stratified-charge combustion in gasoline fueled piston engines. Results are obtained using kinetic-controlled combustion submodel governed by a four-step global chemical reaction or a hybrid laminar kinetics/mixing-controlled combustion submodel that accounts for laminar kinetics and turbulent mixing effects. The numerical solutions are obtained by using KIVA-2 computer code which uses a kinetic-controlled combustion submodel governed by a four-step global chemical reaction (i.e., it assumes that the mixing time is smaller than the chemistry). A hybrid laminar/mixing-controlled combustion submodel was implemented into KIVA-2. In this model, chemical species approach their thermodynamics equilibrium with a rate that is a combination of the turbulent-mixing time and the chemical-kinetics time. The combination is formed in such a way that the longer of the two times has more influence on the conversion rate and the energy release. An additional element of the model is that the laminar-flame kinetics strongly influence the early flame development following ignition.

  13. Twenty-Seventh Symposium (International) on Combustion/The Combustion Institute, 1998/pp. 10571064 UNSTEADY FLAMELET MODELING OF TURBULENT HYDROGEN-AIR

    E-Print Network [OSTI]

    Pitsch, Heinz

    1057 Twenty-Seventh Symposium (International) on Combustion/The Combustion Institute, 1998/pp. 1057-air diffusion flame. An unsteady flamelet is solved interactively with a CFD solver for the tur- bulent flow Modeling of combustion in turbulent diffusion flames has been shown to be already rather success- ful [1

  14. Terascale High-Fidelity Simulations of Turbulent Combustion with Detailed Chemistry: Spray Simulations

    SciTech Connect (OSTI)

    Rutland, Christopher J.

    2009-04-26

    The Terascale High-Fidelity Simulations of Turbulent Combustion (TSTC) project is a multi-university collaborative effort to develop a high-fidelity turbulent reacting flow simulation capability utilizing terascale, massively parallel computer technology. The main paradigm of the approach is direct numerical simulation (DNS) featuring the highest temporal and spatial accuracy, allowing quantitative observations of the fine-scale physics found in turbulent reacting flows as well as providing a useful tool for development of sub-models needed in device-level simulations. Under this component of the TSTC program the simulation code named S3D, developed and shared with coworkers at Sandia National Laboratories, has been enhanced with new numerical algorithms and physical models to provide predictive capabilities for turbulent liquid fuel spray dynamics. Major accomplishments include improved fundamental understanding of mixing and auto-ignition in multi-phase turbulent reactant mixtures and turbulent fuel injection spray jets.

  15. Terascale Direct Numerical Simulations of Turbulent Combustion: Capabilities and Limits (PReSS Talk)

    SciTech Connect (OSTI)

    Yoo, Chun Sang

    2009-03-26

    The rapid growth in computational capabilities has provided great opportunities for direct numerical simulations (DNS) of turbulent combustion, a type of simulations without any turbulence model. With the help of terascale high performance supercomputing (HPC) resources, we are now able to provide fundamental insight into turbulence-chemistry interaction in simple laboratory-scale turbulent flames with detailed chemistry using three-dimensional (3D) DNS. However, the actual domain size of 3D-DNS is still limited within {approx} O(10 cm{sup 3}) due to its tremendously high grid resolution required to resolve the smallest turbulent length scale as well as flame structures. Moreover, 3D-DNS will require more computing powers to investigate next-generation engines, of which operating conditions will be characterized by higher pressures, lower temperatures, and higher levels of dilution. In this talk, I will discuss the capabilities and limits of DNS of turbulent combustion and present some results of ignition/extinction characteristics of a highly diluted hydrogen flame counter-flowing against heated air. The results of our recent 3D-DNS of a spatially-developing turbulent lifted hydrogen jet flame in heated coflow will also be presented. The 3D-DNS was performed at a jet Reynolds number of 11,000 with {approx} 1 billion grid points, which required 3.5 million CPU hours on Cray XT3/XT4 at Oak Ridge National Laboratories.

  16. Lattice Boltzmann equation simulations of turbulence, mixing, and combustion 

    E-Print Network [OSTI]

    Yu, Huidan

    2006-04-12

    We explore the capability of lattice Boltzmann equation (LBE) method for complex fluid flows involving turbulence, mixing, and reaction. In the first study, LBE schemes for binary scalar mixing and multi-component reacting flow with reactions...

  17. Flow, Turbulence and Combustion 65: 393415, 2000. 2001 Kluwer Academic Publishers. Printed in the Netherlands.

    E-Print Network [OSTI]

    Pierce, Niles A.

    Flow, Turbulence and Combustion 65: 393­415, 2000. © 2001 Kluwer Academic Publishers. Printed research groups have developed adjoint CFD codes for de- sign optimisation [3, 4, 6, 8, 22, 29, 30, 44 the adjoint code from an original CFD code; both of these approaches will be discussed further in this paper

  18. TURBULENT COMBUSTION MODELING OF COAL:BIOMASS BLENDS IN A SWIRL BURNER I -PRELIMINARY RESULTS

    E-Print Network [OSTI]

    Daripa, Prabir

    coal or by ex- haust clean up technology. For the power plants, the simplest solution is the preventive- ity well into the 21st century. This dependency on coal calls for better technologies to reduceTURBULENT COMBUSTION MODELING OF COAL:BIOMASS BLENDS IN A SWIRL BURNER I - PRELIMINARY RESULTS

  19. Terascale direct numerical simulations of turbulent combustion using S3D

    SciTech Connect (OSTI)

    Chen, Jackie; Klasky, Scott A; Hawkes, Evatt R; Sankaran, Ramanan; Choudhary, Alok; Yoo, Chun S; Liao, Wei-keng; Podhorszki, Norbert

    2009-01-01

    Computational science is paramount to the understanding of underlying processes in internal combustion engines of the future that will utilize non-petroleum-based alternative fuels, including carbon-neutral biofuels, and burn in new combustion regimes that will attain high efficiency while minimizing emissions of particulates and nitrogen oxides. Next-generation engines will likely operate at higher pressures, with greater amounts of dilution and utilize alternative fuels that exhibit a wide range of chemical and physical properties. Therefore, there is a significant role for high-fidelity simulations, direct numerical simulations (DNS), specifically designed to capture key turbulence-chemistry interactions in these relatively uncharted combustion regimes, and in particular, that can discriminate the effects of differences in fuel properties. In DNS, all of the relevant turbulence and flame scales are resolved numerically using high-order accurate numerical algorithms. As a consequence terascale DNS are computationally intensive, require massive amounts of computing power and generate tens of terabytes of data. Recent results from terascale DNS of turbulent flames are presented here, illustrating its role in elucidating flame stabilization mechanisms in a lifted turbulent hydrogen/air jet flame in a hot air coflow, and the flame structure of a fuel-lean turbulent premixed jet flame. Computing at this scale requires close collaborations between computer and combustion scientists to provide optimized scaleable algorithms and software for terascale simulations, efficient collective parallel I/O, tools for volume visualization of multiscale, multivariate data and automating the combustion workflow. The enabling computer science, applied to combustion science, is also required in many other terascale physics and engineering simulations. In particular, performance monitoring is used to identify the performance of key kernels in the DNS code, S3D and especially memory intensive loops in the code. Through the careful application of loop transformations, data reuse in cache is exploited thereby reducing memory bandwidth needs, and hence, improving S3D's nodal performance. To enhance collective parallel I/O in S3D, an MPI-I/O caching design is used to construct a two-stage write-behind method for improving the performance of write-only operations. The simulations generate tens of terabytes of data requiring analysis. Interactive exploration of the simulation data is enabled by multivariate time-varying volume visualization. The visualization highlights spatial and temporal correlations between multiple reactive scalar fields using an intuitive user interface based on parallel coordinates and time histogram. Finally, an automated combustion workflow is designed using Kepler to manage large-scale data movement, data morphing, and archival and to provide a graphical display of run-time diagnostics.

  20. The role of presumed probability density function in the simulation of non premixed turbulent combustion

    E-Print Network [OSTI]

    Coclite, Alessandro; De Palma, Pietro; Cutrone, Luigi

    2013-01-01

    Flamelet Progress Variable (FPV) combustion models allow the evaluation of all thermo chemical quantities in a reacting flow by computing only the mixture fraction Z and a progress variable C. When using such a method to predict a turbulent combustion in conjunction with a turbulence model, a probability density function (PDF) is required to evaluate statistical averages (e.g., Favre average) of chemical quantities. The choice of the PDF is a compromise between computational costs and accuracy level. The aim of this paper is to investigate the influence of the PDF choice and its modeling aspects in the simulation of non premixed turbulent combustion. Three different models are considered: the standard one, based on the choice of a beta distribution for Z and a Dirac distribution for C; a model employing a beta distribution for both Z and C; a third model obtained using a beta distribution for Z and the statistical most likely distribution (SMLD) for C. The standard model, although widely used, doesn't take in...

  1. Turbulent partially premixed combustion: DNS analysis and RANS simulation

    E-Print Network [OSTI]

    Ruan, S.

    2013-03-12

    energy technologies, such as solar cell, wind power, fuel cell and nuclear energy, significant limitation remains, such as high capital costs, low energy conversion efficiency, and low public acceptance level due to 1 safety and security concerns (US... are separated and only meet in the reacting region through molecular diffusion. The compression-ignition diesel engine is one example. In the premixed mode, fuel and oxidizer (air) are fully mixed at molecular level before they are consumed in the flames...

  2. Locality and stability of the cascades of two-dimensional turbulence.

    E-Print Network [OSTI]

    Gkioulekas, Eleftherios - Department of Mathematics, University of Texas

    chemical combustion Stabilize plasma in a nuclear fusion reactor Propagation of laser through turbulence;Outline Why study turbulence? Brief overview of K41 theory (3D turbulence) Frisch reformulation of K41 theory. KLB theory (2D turbulence). My reformulation of Frisch to address 2D turbulence Locality

  3. Uncertainty quantification of cinematic imaging for development of predictive simulations of turbulent combustion.

    SciTech Connect (OSTI)

    Lawson, Matthew; Debusschere, Bert J.; Najm, Habib N.; Sargsyan, Khachik; Frank, Jonathan H.

    2010-09-01

    Recent advances in high frame rate complementary metal-oxide-semiconductor (CMOS) cameras coupled with high repetition rate lasers have enabled laser-based imaging measurements of the temporal evolution of turbulent reacting flows. This measurement capability provides new opportunities for understanding the dynamics of turbulence-chemistry interactions, which is necessary for developing predictive simulations of turbulent combustion. However, quantitative imaging measurements using high frame rate CMOS cameras require careful characterization of the their noise, non-linear response, and variations in this response from pixel to pixel. We develop a noise model and calibration tools to mitigate these problems and to enable quantitative use of CMOS cameras. We have demonstrated proof of principle for image de-noising using both wavelet methods and Bayesian inference. The results offer new approaches for quantitative interpretation of imaging measurements from noisy data acquired with non-linear detectors. These approaches are potentially useful in many areas of scientific research that rely on quantitative imaging measurements.

  4. Flow, Turbulence and Combustion 73: 95116, 2004. C 2004 Kluwer Academic Publishers. Printed in the Netherlands. 95

    E-Print Network [OSTI]

    Hunt, Julian

    Flow, Turbulence and Combustion 73: 95­116, 2004. C 2004 Kluwer Academic Publishers. Printed in the Netherlands. 95 Disappearing Wakes and Dispersion in Numerically Simulated Flows Through Tube Bundles C 2003; accepted in revised form 11 February 2004 Abstract. Flow through a staggered array or 'bundle

  5. Combustion of a hadronic star into a quark star: the turbulent and the diffusive regimes

    E-Print Network [OSTI]

    Alessandro Drago; Giuseppe Pagliara

    2015-06-27

    We argue that the full conversion of a hadronic star into a quark or a hybrid star occurs within two different regimes separated by a critical value of the density of the hadronic phase $\\overline{n_h}$. The first stage, occurring for $n_h>\\overline{n_h}$, is characterized by turbulent combustion and lasts typically a few ms. During this short time-scale neutrino cooling is basically inactive and the star heats up thanks to the heat released in the conversion. In the second stage, occurring for $n_h<\\overline{n_h}$, turbulence is not active anymore, and the conversion proceeds on a much longer time scale (of the order of tens of seconds), with a velocity regulated by the diffusion and the production of strange quarks. At the same time, neutrino cooling is also active. The interplay between the heating of the star due to the slow conversion of its outer layers (with densities smaller than $\\overline{n_h}$) and the neutrino cooling of the forming quark star leads to a quasi-plateau in the neutrino luminosity which, if observed, would possibly represent a unique signature for the existence of quark matter inside compact stars. We will discuss the phenomenological implications of this scenario in particular in connection with the time structure of long gamma-ray-bursts.

  6. Combustion of a hadronic star into a quark star: the turbulent and the diffusive regimes

    E-Print Network [OSTI]

    Drago, Alessandro

    2015-01-01

    We argue that the full conversion of a hadronic star into a quark or a hybrid star occurs within two different regimes separated by a critical value of the density of the hadronic phase $\\overline{n_h}$. The first stage, occurring for $n_h>\\overline{n_h}$, is characterized by turbulent combustion and lasts typically a few ms. During this short time-scale neutrino cooling is basically inactive and the star heats up thanks to the heat released in the conversion. In the second stage, occurring for $n_h<\\overline{n_h}$, turbulence is not active anymore, and the conversion proceeds on a much longer time scale (of the order of tens of seconds), with a velocity regulated by the diffusion and the production of strange quarks. At the same time, neutrino cooling is also active. The interplay between the heating of the star due to the slow conversion of its outer layers (with densities smaller than $\\overline{n_h}$) and the neutrino cooling of the forming quark star leads to a quasi-plateau in the neutrino luminosity...

  7. Proceedings of the Combustion Institute. Volume 30

    SciTech Connect (OSTI)

    NONE

    2005-01-15

    Papers discussed combustion theory and modelling, turbulent combustion, laser diagnostics and control, chemical kinetics, computational combustion, flames, detonations, droplet combustion, catalysis/materials synthesis, pulse detonations engines, diagnosis, engine combustion, heterogeneous combustion, pollutants (PAH and soot), kinetics, flame diagnosis, propulsion, laminar diffusion flames, lifted turbulent flames, nanoparticles, premixed turbulent flames, solid oxide fuel cells, laminar flames, stationary power systems, and plasma supported flames.

  8. Flow, Turbulence and Combustion 62: 295333, 1999. 1999 Kluwer Academic Publishers. Printed in the Netherlands.

    E-Print Network [OSTI]

    PDF of velocity and turbulent frequency or the joint PDF of velocity, wave vector, and turbulent implemented in conjunction with several velocity models. The complete model yields good comparisons and reaction are treated without mod- eling assumption [3, 4]. In contrast, standard moment closure methods

  9. An SMLD joint PDF model for turbulent non-premixed combustion using the flamelet progress-variable approach

    E-Print Network [OSTI]

    Coclite, Alessandro; De Palma, Pietro; Cutrone, Luigi; Ihme, Matthias

    2015-01-01

    This paper provides an improved flamelet/progress variable (FPV) model for the simulation of turbulent combustion, employing the statistically most likely distribution (SMLD) approach for the joint probability density function (PDF) of the mixture fraction, Z, and of the progress parameter, {\\Lambda} . Steady-state FPV models are built presuming the func- tional shape of the joint PDF of Z and {\\Lambda} in order to evaluate Favre-averages of thermody- namic quantities. The mixture fraction is widely assumed to behave as a passive scalar with a mono-modal behaviour modelled by a \\b{eta} -distribution. Moreover, under the hypothesis that Z and {\\Lambda} are statistically independent, the joint PDF coincides with the product of the two marginal PDFs. In this work we discuss these two constitutive hypotheses. The proposed model evaluates the most probable joint distribution of Z and {\\Lambda} , relaxing some crucial as- sumption on their statistical behaviour. This provides a more general model in the context of ...

  10. ASCR Workshop on Turbulent Flow Simulations at the Exascale: Opportunities and Challenges

    Broader source: Energy.gov [DOE]

    The need for accurate simulation of turbulent flows is evident across the US Department of Energy applied-science and engineering portfolio, including combustion, plasma physics, nuclear-reactor...

  11. Effects of Turbulence on the Combustion Properties of Partially Premixed Flames of Canola Methyl Ester and Diesel Blends

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

    Dhamale, N.; Parthasarathy, R. N.; Gollahalli, S. R.

    2011-01-01

    Canola methyl ester (CME) is a biofuel that is a renewable alternative energy resource and is produced by the transesterification of canola oil. The objective of this study was to document the effects of turbulence on the combustion characteristics of blends of CME and No 2 diesel fuel in a partially-premixed flame environment. The experiments were conducted with mixtures of pre-vaporized fuel and air at an initial equivalence ratio of 7 and three burner exit Reynolds numbers, 2700, 3600, and 4500. Three blends with 25, 50, and 75% volume concentration of CME were studied. The soot volume fraction was highestmore »for the pure diesel flames and did not change significantly with Reynolds number due to the mutually compensating effects of increased carbon input rate and increased air entrainment as the Reynolds number was increased. The global NOx emission index was highest and the CO emission index was the lowest for the pure CME flame, and varied non-monotonically with biofuel content in the blend The mean temperature and the NOx concentration at three-quarter flame height were generally correlated, indicating that the thermal mechanism of NOx formation was dominant in the turbulent biofuel flames also.« less

  12. Simulation of Turbulent Combustion Fields of Shock-Dispersed Aluminum Using the AMR Code

    SciTech Connect (OSTI)

    Kuhl, A L; Bell, J B; Beckner, V E; Khasainov, B

    2006-11-02

    We present a Model for simulating experiments of combustion in Shock-Dispersed-Fuel (SDF) explosions. The SDF charge consisted of a 0.5-g spherical PETN booster, surrounded by 1-g of fuel powder (flake Aluminum). Detonation of the booster charge creates a high-temperature, high-pressure source (PETN detonation products gases) that both disperses the fuel and heats it. Combustion ensues when the fuel mixes with air. The gas phase is governed by the gas-dynamic conservation laws, while the particle phase obeys the continuum mechanics laws for heterogeneous media. The two phases exchange mass, momentum and energy according to inter-phase interaction terms. The kinetics model used an empirical particle burn relation. The thermodynamic model considers the air, fuel and booster products to be of frozen composition, while the Al combustion products are assumed to be in equilibrium. The thermodynamic states were calculated by the Cheetah code; resulting state points were fit with analytic functions suitable for numerical simulations. Numerical simulations of combustion of an Aluminum SDF charge in a 6.4-liter chamber were performed. Computed pressure histories agree with measurements.

  13. AMR Code Simulations of Turbulent Combustion in Confined and Unconfined SDF Explosions

    SciTech Connect (OSTI)

    Kuhl, A L; Bell, J B; Beckner, V

    2009-05-29

    A heterogeneous continuum model is proposed to describe the dispersion and combustion of an aluminum particle cloud in an explosion. It combines the gas-dynamic conservation laws for the gas phase with a continuum model for the dispersed phase, as formulated by Nigmatulin. Inter-phase mass, momentum and energy exchange are prescribed by phenomenological models. It incorporates a combustion model based on the mass conservation laws for fuel, air and products; source/sink terms are treated in the fast-chemistry limit appropriate for such gas dynamic fields, along with a model for mass transfer from the particle phase to the gas. The model takes into account both the afterburning of the detonation products of the booster with air, and the combustion of the Al particles with air. The model equations were integrated by high-order Godunov schemes for both the gas and particle phases. Numerical simulations of the explosion fields from 1.5-g Shock-Dispersed-Fuel (SDF) charge in a 6.6 liter calorimeter were used to validate the combustion model. Then the model was applied to 10-kg Al-SDF explosions in a vented two-room structure and in an unconfined height-of-burst explosion. Computed pressure histories are in reasonable (but not perfect) agreement with measured waveforms. Differences are caused by physical-chemical kinetic effects of particle combustion which induce ignition delays in the initial reactive blast wave and quenching of reactions at late times. Current simulations give initial insights into such modeling issues.

  14. Computational Combustion

    SciTech Connect (OSTI)

    Westbrook, C K; Mizobuchi, Y; Poinsot, T J; Smith, P J; Warnatz, J

    2004-08-26

    Progress in the field of computational combustion over the past 50 years is reviewed. Particular attention is given to those classes of models that are common to most system modeling efforts, including fluid dynamics, chemical kinetics, liquid sprays, and turbulent flame models. The developments in combustion modeling are placed into the time-dependent context of the accompanying exponential growth in computer capabilities and Moore's Law. Superimposed on this steady growth, the occasional sudden advances in modeling capabilities are identified and their impacts are discussed. Integration of submodels into system models for spark ignition, diesel and homogeneous charge, compression ignition engines, surface and catalytic combustion, pulse combustion, and detonations are described. Finally, the current state of combustion modeling is illustrated by descriptions of a very large jet lifted 3D turbulent hydrogen flame with direct numerical simulation and 3D large eddy simulations of practical gas burner combustion devices.

  15. Computing supersonic non-premixed turbulent combustion by an SMLD flamelet progress variable model

    E-Print Network [OSTI]

    Coclite, A; Gurtner, M; De Palma, P; Haidnd, O J; Pascazio, G

    2015-01-01

    This paper describes the numerical simulation of the NASA Langley Research Center supersonic H2 -Air combustion chamber performed using two approaches to model the presumed probability density function (PDF) in the flamelet progress variable (FPV) framework. The first one is a standard FPV model, built presuming the functional shape of the PDFs of the mixture fraction, Z, and of the progress parameter, {\\Lambda}. In order to enhance the prediction capabilities of such a model in high-speed reacting flows, a second approach is proposed employing the statistically most likely distribution (SMLD) techcnique to presume the joint PDF of Z and {\\Lambda}, without any assumption about their behaviour. The standard and FPV-SMLD models have been developed using the low Mach number assumption. In both cases, the temperature is evaluated by solving the total-energy conservation equation, providing a more suitable approach for the simulation of supersonic combustion. By comparison with experimental data, the proposed SMLD...

  16. COMBUSTION RESEARCH PROGRAM. CHAPTER FROM ENERGY & ENVIRONMENT ANNUAL REPORT 1977

    E-Print Network [OSTI]

    Authors, Various

    2011-01-01

    Applied to Turbulent Combustion Flows J. W. Daily and C.Metals from Pulverized Coal Combustion P. Sherman and F.Applied to Turbulent Combustion Flows J. W. Daily and C.

  17. Towards predicting dynamics in turbulent premixed combustion using PIV-PLIF measurements of flow-flame microstructure

    E-Print Network [OSTI]

    Hong, Seung Hyuck

    2014-01-01

    Combustion dynamics are critical to the development of high-efficiency, low-emission and fuel-flexible combustion systems used for propulsion and power generation. Predicting the onset of dynamics remains a challenge because ...

  18. Simulations of a turbulent non-premixed flame using combined dimension reduction and tabulation for combustion chemistry

    E-Print Network [OSTI]

    Simulations of a turbulent non-premixed flame using combined dimension reduction and tabulation simulate a bluff-body-stabilized non-premixed turbulent methane/air flame. " NOx and CO emissions have been flames Dimension reduction Tabulation Constrained equilibrium a b s t r a c t The use of large chemical

  19. Proceedings of the Combustion Institute, Volume 28, 2000/pp. 903910 TURBULENT FLAME DYNAMICS OF HOMOGENEOUS SOLID PROPELLANT

    E-Print Network [OSTI]

    Apte, Sourabh V.

    luminous flame. The enhanced energy and mass transport in the turbulent region partially merges the primary-eddy-simulation technique. The contribution of large energy-carrying structures to mass, momentum, and energy transfer into the primary flame zone. The turbulence energy spectra indicate dominant harmonics in a frequency range capable

  20. An analytical investigation of primary zone combustion temperatures and NOx production for turbulent jet flames using low-BTU fuels 

    E-Print Network [OSTI]

    Carney, Christopher Mark

    1995-01-01

    The objective of this research project was to identify and determine the effect of jet burner operating variables that influence combustion of low-BTU gases. This was done by simulating the combustion of a low-BTU fuel in a jet flame and predicting...

  1. Sandia Energy - Turbulent Combustion

    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 RoomPreservation of Fe(II)GeothermalFuel MagnetizationTransportation Energy HomeTuesday September

  2. Large-eddy simulations of turbulent flow for grid-to-rod fretting in nuclear reactors

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

    Bakosi, J.; Christon, M. A.; Lowrie, R. B.; Pritchett-Sheats, L. A.; Nourgaliev, R. R.

    2013-07-12

    The grid-to-rod fretting (GTRF) problem in pressurized water reactors is a flow-induced vibration problem that results in wear and failure of the fuel rods in nuclear assemblies. In order to understand the fluid dynamics of GTRF and to build an archival database of turbulence statistics for various configurations, implicit large-eddy simulations of time-dependent single-phase turbulent flow have been performed in 3 × 3 and 5 × 5 rod bundles with a single grid spacer. To assess the computational mesh and resolution requirements, a method for quantitative assessment of unstructured meshes with no-slip walls is described. The calculations have been carriedmore »out using Hydra-TH, a thermal-hydraulics code developed at Los Alamos for the Consortium for Advanced Simulation of Light water reactors, a United States Department of Energy Innovation Hub. Hydra-TH uses a second-order implicit incremental projection method to solve the singlephase incompressible Navier-Stokes equations. The simulations explicitly resolve the large scale motions of the turbulent flow field using first principles and rely on a monotonicity-preserving numerical technique to represent the unresolved scales. Each series of simulations for the 3 × 3 and 5 × 5 rod-bundle geometries is an analysis of the flow field statistics combined with a mesh-refinement study and validation with available experimental data. Our primary focus is the time history and statistics of the forces loading the fuel rods. These hydrodynamic forces are believed to be the key player resulting in rod vibration and GTRF wear, one of the leading causes for leaking nuclear fuel which costs power utilities millions of dollars in preventive measures. As a result, we demonstrate that implicit large-eddy simulation of rod-bundle flows is a viable way to calculate the excitation forces for the GTRF problem.« less

  3. Combustion Energy Frontier Research Center Post-Doctoral Position...

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

    University and Sandia National Laboratories on advanced simulations of turbulent combustion. The project involves two simulation methodologies: direct numerical simulation...

  4. FLAME SURFACE DENSITIES IN PREMIXED COMBUSTION AT MEDIUM TO HIGH

    E-Print Network [OSTI]

    Gülder, Ömer L.

    FLAME SURFACE DENSITIES IN PREMIXED COMBUSTION AT MEDIUM TO HIGH TURBULENCE INTENSITIES O¨ MER L in turbulent premixed propane= air flames were determined experimentally. The instantaneous flame fronts were combustion regime as defined by the most recent turbulent premixed combustion dia- grams. From 100 to 800

  5. Large-eddy simulations of turbulent flow for grid-to-rod fretting in nuclear reactors

    E-Print Network [OSTI]

    Bakosi, J; Lowrie, R B; Pritchett-Sheats, L A; Nourgaliev, R R

    2013-01-01

    The grid-to-rod fretting (GTRF) problem in pressurized water reactors is a flow-induced vibration problem that results in wear and failure of the fuel rods in nuclear assemblies. In order to understand the fluid dynamics of GTRF and to build an archival database of turbulence statistics for various configurations, implicit large-eddy simulations of time-dependent single-phase turbulent flow have been performed in 3x3 and 5x5 rod bundles with a single grid spacer. To assess the computational mesh and resolution requirements, a method for quantitative assessment of unstructured meshes with no-slip walls is described. The calculations have been carried out using Hydra-TH, a thermal-hydraulics code developed at Los Alamos for the Consortium for Advanced Simulation of Light water reactors, a United States Department of Energy Innovation Hub. Hydra-TH uses a second-order implicit incremental projection method to solve the single-phase incompressible Navier-Stokes equations. The simulations explicitly resolve the la...

  6. IR-laser initiated combustion -- A step toward complete combustion

    SciTech Connect (OSTI)

    Laghai, A.; Nabavi, S.H.; Servati, H.B.; Syed, F.

    1996-09-01

    The new global environmental regulations for reducing the engine emissions from both moving and stationary sources, as well as improvement in fuel economy are the major motifs to obtain a perfect combustion process and exhaust aftertreatment methods. Infrared (IR)-Laser initiated combustion provides a very high initial temperature, which produces propagation of a turbulent thermopressure pulse that results in a fast burning and improved combustion. The role of IR is to maximize the heat generation efficiency.

  7. Hydrogen-or-Fossil-Combustion Nuclear Combined-Cycle Systems for Base- and Peak-Load Electricity Production

    SciTech Connect (OSTI)

    Forsberg, Charles W; Conklin, Jim

    2007-09-01

    A combined-cycle power plant is described that uses (1) heat from a high-temperature nuclear reactor to meet base-load electrical demands and (2) heat from the same high-temperature reactor and burning natural gas, jet fuel, or hydrogen to meet peak-load electrical demands. For base-load electricity production, fresh air is compressed; then flows through a heat exchanger, where it is heated to between 700 and 900 C by heat provided by a high-temperature nuclear reactor via an intermediate heat-transport loop; and finally exits through a high-temperature gas turbine to produce electricity. The hot exhaust from the Brayton-cycle gas turbine is then fed to a heat recovery steam generator that provides steam to a steam turbine for added electrical power production. To meet peak electricity demand, the air is first compressed and then heated with the heat from a high-temperature reactor. Natural gas, jet fuel, or hydrogen is then injected into the hot air in a combustion chamber, combusts, and heats the air to 1300 C-the operating conditions for a standard natural-gas-fired combined-cycle plant. The hot gas then flows through a gas turbine and a heat recovery steam generator before being sent to the exhaust stack. The higher temperatures increase the plant efficiency and power output. If hydrogen is used, it can be produced at night using energy from the nuclear reactor and stored until needed. With hydrogen serving as the auxiliary fuel for peak power production, the electricity output to the electric grid can vary from zero (i.e., when hydrogen is being produced) to the maximum peak power while the nuclear reactor operates at constant load. Because nuclear heat raises air temperatures above the auto-ignition temperatures of the various fuels and powers the air compressor, the power output can be varied rapidly (compared with the capabilities of fossil-fired turbines) to meet spinning reserve requirements and stabilize the electric grid. This combined cycle uses the unique characteristics of high-temperature reactors (T>700 C) to produce electricity for premium electric markets whose demands can not be met by other types of nuclear reactors. It may also make the use of nuclear reactors economically feasible in smaller electrical grids, such as those found in many developing countries. The ability to rapidly vary power output can be used to stabilize electric grid performance-a particularly important need in small electrical grids.

  8. Numerical approaches to combustion modeling. Progress in Astronautics and Aeronautics. Vol. 135

    SciTech Connect (OSTI)

    Oran, E.S.; Boris, J.P. )

    1991-01-01

    Various papers on numerical approaches to combustion modeling are presented. The topics addressed include; ab initio quantum chemistry for combustion; rate coefficient calculations for combustion modeling; numerical modeling of combustion of complex hydrocarbons; combustion kinetics and sensitivity analysis computations; reduction of chemical reaction models; length scales in laminar and turbulent flames; numerical modeling of laminar diffusion flames; laminar flames in premixed gases; spectral simulations of turbulent reacting flows; vortex simulation of reacting shear flow; combustion modeling using PDF methods. Also considered are: supersonic reacting internal flow fields; studies of detonation initiation, propagation, and quenching; numerical modeling of heterogeneous detonations, deflagration-to-detonation transition to reactive granular materials; toward a microscopic theory of detonations in energetic crystals; overview of spray modeling; liquid drop behavior in dense and dilute clusters; spray combustion in idealized configurations: parallel drop streams; comparisons of deterministic and stochastic computations of drop collisions in dense sprays; ignition and flame spread across solid fuels; numerical study of pulse combustor dynamics; mathematical modeling of enclosure fires; nuclear systems.

  9. Simulation of Lean Premixed Turbulent Combustion J. Bell1, M. Day1, A. Almgren1, M. Lijewski1, C. Rendleman1, R.

    E-Print Network [OSTI]

    Bell, John B.

    . There is considerable technological interest in developing new fuel-flexible combustion systems that can burn fuels such as hydrogen or syngas. Lean premixed systems have the potential to burn these types of fuels with high understanding of premixed combustion, they are unable to meet the challenges of designing fuel-flexible lean

  10. Standard guide for pyrophoricity/combustibility testing in support of pyrophoricity analyses of metallic uranium spent nuclear fuel

    E-Print Network [OSTI]

    American Society for Testing and Materials. Philadelphia

    2007-01-01

    1.1 This guide covers testing protocols for testing the pyrophoricity/combustibility characteristics of metallic uranium-based spent nuclear fuel (SNF). The testing will provide basic data for input into more detailed computer codes or analyses of thermal, chemical, and mechanical SNF responses. These analyses would support the engineered barrier system (EBS) design bases and safety assessment of extended interim storage facilities and final disposal in a geologic repository. The testing also could provide data related to licensing requirements for the design and operation of a monitored retrievable storage facility (MRS) or independent spent fuel storage installation (ISFSI). 1.2 This guide describes testing of metallic uranium and metallic uranium-based SNF in support of transportation (in accordance with the requirements of 10CFR71), interim storage (in accordance with the requirements of 10CFR72), and geologic repository disposal (in accordance with the requirements of 10CFR60/63). The testing described ...

  11. Studies in combustion dynamics

    SciTech Connect (OSTI)

    Koszykowski, M.L. [Sandia National Laboratories, Livermore, CA (United States)

    1993-12-01

    The goal of this program is to develop a fundamental understanding and a quantitative predictive capability in combustion modeling. A large part of the understanding of the chemistry of combustion processes comes from {open_quotes}chemical kinetic modeling.{close_quotes} However, successful modeling is not an isolated activity. It necessarily involves the integration of methods and results from several diverse disciplines and activities including theoretical chemistry, elementary reaction kinetics, fluid mechanics and computational science. Recently the authors have developed and utilized new tools for parallel processing to implement the first numerical model of a turbulent diffusion flame including a {open_quotes}full{close_quotes} chemical mechanism.

  12. Terascale direct numerical simulations of turbulent combustion using S3D This article has been downloaded from IOPscience. Please scroll down to see the full text article.

    E-Print Network [OSTI]

    was downloaded on 12/09/2010 at 06:04 Please note that terms and conditions apply. View the table of contents combustion engines of the future that will utilize non-petroleum-based alternative fuels, including carbon amounts of dilution and utilize alternative fuels that exhibit a wide range of chemical and physical

  13. Twenty-Seventh Symposium (International) on Combustion/The Combustion Institute, 1998/pp. 693702 COMPUTATIONAL AND EXPERIMENTAL STUDY OF A FORCED, TIME-

    E-Print Network [OSTI]

    Long, Marshall B.

    's cyclic history. Introduction Most practical combustion systems, such as gas turbines and industrial693 Twenty-Seventh Symposium (International) on Combustion/The Combustion Institute, 1998/pp. 693 systems that help bridge the gap between laminar and turbulent combustion. In this study, we investigate

  14. Jet plume injection and combustion system for internal combustion engines

    DOE Patents [OSTI]

    Oppenheim, Antoni K. (Kensington, CA); Maxson, James A. (Berkeley, CA); Hensinger, David M. (Albany, CA)

    1993-01-01

    An improved combustion system for an internal combustion engine is disclosed wherein a rich air/fuel mixture is furnished at high pressure to one or more jet plume generator cavities adjacent to a cylinder and then injected through one or more orifices from the cavities into the head space of the cylinder to form one or more turbulent jet plumes in the head space of the cylinder prior to ignition of the rich air/fuel mixture in the cavity of the jet plume generator. The portion of the rich air/fuel mixture remaining in the cavity of the generator is then ignited to provide a secondary jet, comprising incomplete combustion products which are injected into the cylinder to initiate combustion in the already formed turbulent jet plume. Formation of the turbulent jet plume in the head space of the cylinder prior to ignition has been found to yield a higher maximum combustion pressure in the cylinder, as well as shortening the time period to attain such a maximum pressure.

  15. Jet plume injection and combustion system for internal combustion engines

    DOE Patents [OSTI]

    Oppenheim, A.K.; Maxson, J.A.; Hensinger, D.M.

    1993-12-21

    An improved combustion system for an internal combustion engine is disclosed wherein a rich air/fuel mixture is furnished at high pressure to one or more jet plume generator cavities adjacent to a cylinder and then injected through one or more orifices from the cavities into the head space of the cylinder to form one or more turbulent jet plumes in the head space of the cylinder prior to ignition of the rich air/fuel mixture in the cavity of the jet plume generator. The portion of the rich air/fuel mixture remaining in the cavity of the generator is then ignited to provide a secondary jet, comprising incomplete combustion products which are injected into the cylinder to initiate combustion in the already formed turbulent jet plume. Formation of the turbulent jet plume in the head space of the cylinder prior to ignition has been found to yield a higher maximum combustion pressure in the cylinder, as well as shortening the time period to attain such a maximum pressure. 24 figures.

  16. Sealed Combustion

    SciTech Connect (OSTI)

    2009-05-12

    This information sheet discusses the benefits of sealed combustion appliance units in order to ensure good indoor air quality.

  17. Proceedings of the Combustion Institute, Volume 29, 2002/pp. 19711978 IMPROVED POLLUTANT PREDICTIONS IN LARGE-EDDY SIMULATIONS

    E-Print Network [OSTI]

    Pitsch, Heinz

    1971 Proceedings of the Combustion Institute, Volume 29, 2002/pp. 1971­1978 IMPROVED POLLUTANT PREDICTIONS IN LARGE-EDDY SIMULATIONS OF TURBULENT NON-PREMIXED COMBUSTION BY CONSIDERING SCALAR DISSIPATION-eddy simulation (LES) of turbulent combustion has become a subject of in- tensive research and modeling efforts

  18. Oscillatory Flame Response in Acoustically Coupled Fuel Droplet Combustion

    E-Print Network [OSTI]

    Sevilla Esparza, Cristhian Israel

    2013-01-01

    CombustionCombustion . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .Coupled Droplet Combustion . . . . . . . . . . . . Burning

  19. Hybrid fluidized bed combuster

    DOE Patents [OSTI]

    Kantesaria, Prabhudas P. (Windsor, CT); Matthews, Francis T. (Poquonock, CT)

    1982-01-01

    A first atmospheric bubbling fluidized bed furnace is combined with a second turbulent, circulating fluidized bed furnace to produce heat efficiently from crushed solid fuel. The bed of the second furnace receives the smaller sizes of crushed solid fuel, unreacted limestone from the first bed, and elutriated solids extracted from the flu gases of the first bed. The two-stage combustion of crushed solid fuel provides a system with an efficiency greater than available with use of a single furnace of a fluidized bed.

  20. Advanced Combustion

    SciTech Connect (OSTI)

    Holcomb, Gordon R.

    2013-03-05

    Topics covered in this presentation include: the continued importance of coal; related materials challenges; combining oxy-combustion & A-USC steam; and casting large superalloy turbine components.

  1. A new robust consistent hybrid finite-volume/particle method for solving the PDF model equations of turbulent reactive flows

    E-Print Network [OSTI]

    Muradoglu, Metin

    and pollution are directly related to the conversion of chemical energy into thermal energy via combustion Available online 10 September 2014 Keywords: PDF methods Consistent hybrid method Turbulent combustion Bluff rights reserved. 1. Introduction Turbulent combustion continues to be a key technology in energy

  2. Combustion Noise

    E-Print Network [OSTI]

    Dowling, Ann P.; Mahmoudi, Yasser

    2014-01-01

    Combustion noise is becoming increasingly important as a major noise source in aeroengines and ground based gas turbines. This is partially because advances in design have reduced the other noise sources, and partially because next generation...

  3. Applied combustion

    SciTech Connect (OSTI)

    1993-12-31

    From the title, the reader is led to expect a broad practical treatise on combustion and combustion devices. Remarkably, for a book of modest dimension, the author is able to deliver. The text is organized into 12 Chapters, broadly treating three major areas: combustion fundamentals -- introduction (Ch. 1), thermodynamics (Ch. 2), fluid mechanics (Ch. 7), and kinetics (Ch. 8); fuels -- coal, municipal solid waste, and other solid fuels (Ch. 4), liquid (Ch. 5) and gaseous (Ch. 6) fuels; and combustion devices -- fuel cells (Ch. 3), boilers (Ch. 4), Otto (Ch. 10), diesel (Ch. 11), and Wankel (Ch. 10) engines and gas turbines (Ch. 12). Although each topic could warrant a complete text on its own, the author addresses each of these major themes with reasonable thoroughness. Also, the book is well documented with a bibliography, references, a good index, and many helpful tables and appendices. In short, Applied Combustion does admirably fulfill the author`s goal for a wide engineering science introduction to the general subject of combustion.

  4. Assessment of Dynamic Closure for Premixed Combustion LES

    E-Print Network [OSTI]

    Langella, Ivan; Swaminathan, Nedunchezhian; Gao, Yuan; Chakraborty, Nilanjan

    2015-08-04

    model 1. Introduction High efficiency and low emission can be achieved simultaneously for power plants used in transport sectors, specifically gas turbines, using lean turbulent premixed combustion. A strong interplay between thermochemical and fluid... stream_source_info Langella et al 2015 Combustion Theory and Modelling.pdf.txt stream_content_type text/plain stream_size 77455 Content-Encoding UTF-8 stream_name Langella et al 2015 Combustion Theory and Modelling.pdf.txt Content...

  5. Generation and amplification of acoustic waves by thermal process - 2. Thermoacoustics effects in combustion

    SciTech Connect (OSTI)

    Abugov, D.I.; Obrezkov, O.I.

    1980-01-01

    Results are presented of a theoretical analysis of thermoacoustic effects observed during combustion, i.e., turbulent flame noise, amplification of acoustic waves by the combustion front, and acoustic instability of combustion in through-flow chambers. Relations are obtained which describe these phenomena. 8 refs.

  6. Combustion Theory and Modelling Vol. 11, No. 5, October 2007, 697714

    E-Print Network [OSTI]

    Sidorov, Nikita

    Combustion Theory and Modelling Vol. 11, No. 5, October 2007, 697­714 Flame propagation in a small, to the emerging micro-combustion technology, and to the understanding of the effect of small scales; Turbulent combustion 1. Introduction The propagation of premixed flames in the presence of a flow whose

  7. COMBUSTION RESEARCH - FY-1979

    E-Print Network [OSTI]

    ,

    2012-01-01

    Optical Measurement of Combustion Products by Zeeman Atomicand T. Hadeishi • . . • . • . • • . • Combustion Sources offrom Pulverized Coal Combustion J. Pennucci, R. Greif, F.

  8. Turbulent Combustion in Type Ia Supernova Models

    E-Print Network [OSTI]

    F. K. Roepke; W. Hillebrandt

    2006-09-15

    We review the astrophysical modeling of type Ia supernova explosions and describe numerical methods to implement numerical simulations of these events. Some results of such simulations are discussed.

  9. 3 - 4 Turbulent combustion Princeton.key

    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 RoomPreservationBio-InspiredAtmosphericdevicesPPONeApril 30,University RegistrationNeed2 2D7P D

  10. Advanced Computational Methods for Turbulence and Combustion

    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 News Publications Traditional Knowledge KiosksAboutHelp & Reference UsersAdvanced

  11. Sandia Energy - DISI Combustion

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

    DISI Combustion Home Transportation Energy Predictive Simulation of Engines Combustion Chemistry DISI Combustion DISI CombustionAshley Otero2015-10-28T02:44:30+00:00...

  12. Sandia Energy - Spray Combustion

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

    Spray Combustion Home Transportation Energy Predictive Simulation of Engines Engine Combustion Fuels Spray Combustion Spray CombustionAshley Otero2015-10-28T02:17:06+00:00 Fuel...

  13. Sandia Energy - Spray Combustion

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

    Spray Combustion Home Transportation Energy Predictive Simulation of Engines Engine Combustion Heavy Duty Spray Combustion Spray CombustionAshley Otero2015-10-28T02:00:56+00:00...

  14. Response of turbulent premixed flames to harmonic acoustic forcing

    E-Print Network [OSTI]

    Lieuwen, Timothy C.

    for land- based gas turbines, future aircraft engines, industrial heaters and boilers rely on premixed 1540 2006 The Combustion Institute. Published by Elsevier Inc. All rights reserved. Keywords: Flame area to a harmonic disturbance of given amplitude depends upon turbulence intensity. Low emissions combustion systems

  15. Comparative Study of Modeling a Hydrogen Nonpremixed Turbulent Flame

    E-Print Network [OSTI]

    Daraio, Chiara

    of furnaces or gas turbines as well as for the prediction of pollutants such as nitrogen oxides. with different combustion models. The predictions are validated against existing experimental data provided [1, 2]. In particular, a comparison of two "advanced" turbulent combustion models is presented

  16. LES of a Hydrogen-Enriched Lean Turbulent Premixed Flame

    E-Print Network [OSTI]

    Groth, Clinton P. T.

    - tends the lean stability limit and decreases emissions of carbon monoxide (CO), nitrogen oxides (NOx) to the prediction of H2-enriched lean methane-air turbulent premixed combustion is considered. A presumed conditional mo- ment (PCM) subfilter-scale combustion model is coupled with the flame prolongation

  17. NUMERICAL INVESTIGATION OF AN ANISOTHERMAL TURBULENT FLOW WITH EFFUSION

    E-Print Network [OSTI]

    Nicoud, Franck

    NUMERICAL INVESTIGATION OF AN ANISOTHERMAL TURBULENT FLOW WITH EFFUSION Simon Mendez CFD Team the plate. CONTEXT In gas turbines, the turbine blades and the liner of the combustion chamber are submitted. For economical reasons, computational fluid dynamics is now widely used as a design tool by combustion cham- ber

  18. Numerical simulation of turbulent jet primary breakup in Diesel engines

    E-Print Network [OSTI]

    Helluy, Philippe

    Turbulence Mixture Fraction Spray mass coupling evaporation rate moment coupling mixing heat exchange Spray 2 Bernd Binninger1 Norbert Peters1 1 Institute for Combustion Technology RWTH-Aachen 2 Mechanical composition pollutant formation Combustion stability Need to accurately model Spray Process From injection

  19. Turbulence-chemistry interactions in reacting flows

    SciTech Connect (OSTI)

    Barlow, R.S.; Carter, C.D. [Sandia National Laboratories, Livermore, CA (United States)

    1993-12-01

    Interactions between turbulence and chemistry in nonpremixed flames are investigated through multiscalar measurements. Simultaneous point measurements of major species, NO, OH, temperature, and mixture fraction are obtained by combining spontaneous Raman scattering, Rayleigh scattering, and laser-induced fluorescence (LIF). NO and OH fluorescence signals are converted to quantitative concentrations by applying shot-to-shot corrections for local variations of the Boltzmann fraction and collisional quenching rate. These measurements of instantaneous thermochemical states in turbulent flames provide insights into the fundamental nature of turbulence-chemistry interactions. The measurements also constitute a unique data base for evaluation and refinement of turbulent combustion models. Experimental work during the past year has focused on three areas: (1) investigation of the effects of differential molecular diffusion in turbulent combustion: (2) experiments on the effects of Halon CF{sub 3}Br, a fire retardant, on the structure of turbulent flames of CH{sub 4} and CO/H{sub 2}/N{sub 2}; and (3) experiments on NO formation in turbulent hydrogen jet flames.

  20. Regenerative combustion device

    DOE Patents [OSTI]

    West, Phillip B.

    2004-03-16

    A regenerative combustion device having a combustion zone, and chemicals contained within the combustion zone, such as water, having a first equilibrium state, and a second combustible state. Means for transforming the chemicals from the first equilibrium state to the second combustible state, such as electrodes, are disposed within the chemicals. An igniter, such as a spark plug or similar device, is disposed within the combustion zone for igniting combustion of the chemicals in the second combustible state. The combustion products are contained within the combustion zone, and the chemicals are selected such that the combustion products naturally chemically revert into the chemicals in the first equilibrium state following combustion. The combustion device may thus be repeatedly reused, requiring only a brief wait after each ignition to allow the regeneration of combustible gasses within the head space.

  1. Light Duty Combustion Research: Advanced Light-Duty Combustion...

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

    Light Duty Combustion Research: Advanced Light-Duty Combustion Experiments Light Duty Combustion Research: Advanced Light-Duty Combustion Experiments 2009 DOE Hydrogen Program and...

  2. Advanced Combustion

    SciTech Connect (OSTI)

    Holcomb, Gordon R.

    2013-03-11

    The activity reported in this presentation is to provide the mechanical and physical property information needed to allow rational design, development and/or choice of alloys, manufacturing approaches, and environmental exposure and component life models to enable oxy-fuel combustion boilers to operate at Ultra-Supercritical (up to 650{degrees}C & between 22-30 MPa) and/or Advanced Ultra-Supercritical conditions (760{degrees}C & 35 MPa).

  3. Turbulence and combustion interaction: High resolution local flame front structure visualization using simultaneous single-shot PLIF imaging of CH, OH, and CH{sub 2}O in a piloted premixed jet flame

    SciTech Connect (OSTI)

    Li, Z.S.; Li, B.; Sun, Z.W.; Alden, M. [Division of Combustion Physics, Lund University, P.O. Box 118, S-221 00 Lund (Sweden); Bai, X.S. [Division of Fluid Mechanics, Lund University, P.O. Box 118, S-221 00 Lund (Sweden)

    2010-06-15

    High resolution planar laser-induced fluorescence (PLIF) was applied to investigate the local flame front structures of turbulent premixed methane/air jet flames in order to reveal details about turbulence and flame interaction. The targeted turbulent flames were generated on a specially designed coaxial jet burner, in which low speed stoichiometric gas mixture was fed through the outer large tube to provide a laminar pilot flame for stabilization of the high speed jet flame issued through the small inner tube. By varying the inner tube flow speed and keeping the mixture composition as that of the outer tube, different flames were obtained covering both the laminar and turbulent flame regimes with different turbulent intensities. Simultaneous CH/CH{sub 2}O, and also OH PLIF images were recorded to characterize the influence of turbulence eddies on the reaction zone structure, with a spatial resolution of about 40 {mu}m and temporal resolution of around 10 ns. Under all experimental conditions, the CH radicals were found to exist only in a thin layer; the CH{sub 2}O were found in the inner flame whereas the OH radicals were seen in the outer flame with the thin CH layer separating the OH and CH{sub 2}O layers. The outer OH layer is thick and it corresponds to the oxidation zone and post-flame zone; the CH{sub 2}O layer is thin in laminar flows; it becomes broad at high speed turbulent flow conditions. This phenomenon was analyzed using chemical kinetic calculations and eddy/flame interaction theory. It appears that under high turbulence intensity conditions, the small eddies in the preheat zone can transport species such as CH{sub 2}O from the reaction zones to the preheat zone. The CH{sub 2}O species are not consumed in the preheat zone due to the absence of H, O, and OH radicals by which CH{sub 2}O is to be oxidized. The CH radicals cannot exist in the preheat zone due to the rapid reactions of this species with O{sub 2} and CO{sub 2} in the inner-layer of the reaction zones. The local PLIF intensities were evaluated using an area integrated PLIF signal. Substantial increase of the CH{sub 2}O signal and decrease of CH signal was observed as the jet velocity increases. These observations raise new challenges to the current flamelet type models. (author)

  4. Combustion & Health 

    E-Print Network [OSTI]

    Hamilton, W.

    2012-01-01

    stream_source_info ESL-KT-12-10-18.pdf.txt stream_content_type text/plain stream_size 4107 Content-Encoding ISO-8859-1 stream_name ESL-KT-12-10-18.pdf.txt Content-Type text/plain; charset=ISO-8859-1 FFCOMBUSTION & HEALTH... Winifred J. Hamilton, PhD, SM Clear Air Through Energy Efficiency (CATEE) Galveston, TX October 9?11, 2012 FFCOMBUSTION & HEALTH FFCOMBUSTION: THE THREAT ? Biggest threat to world ecosystems (and to human health) ? Combustion of fossil fuels...

  5. Sandia Energy - Combustion Kinetics

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

    Kinetics Home Transportation Energy Predictive Simulation of Engines Combustion Chemistry Combustion Kinetics Combustion KineticsAshley Otero2015-10-28T02:45:13+00:00 The...

  6. Sandia Energy - DISI Combustion

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

    Home Transportation Energy Predictive Simulation of Engines Engine Combustion Automotive DISI Combustion DISI CombustionAshley Otero2015-10-28T02:06:42+00:00 DISI engine in...

  7. Turbulence of a Unidirectional Flow Bjorn Birnir

    E-Print Network [OSTI]

    Birnir, Björn

    -flying aircraft. Turbulent drag also prevents the design of more fuel-efficient cars and aircrafts. Turbulence plays a role in the heat trans- fer in nuclear reactors, causes drag in oil pipelines and influence and intrigued people for centuries. Five centuries ago a fluid engineer by the name of Leonardo da Vinci tackled

  8. A filtered tabulated chemistry model for LES of premixed combustion

    SciTech Connect (OSTI)

    Fiorina, B.; Auzillon, P.; Darabiha, N.; Gicquel, O.; Veynante, D. [EM2C - CNRS, Ecole Centrale Paris, 92295 Chatenay Malabry (France); Vicquelin, R. [EM2C - CNRS, Ecole Centrale Paris, 92295 Chatenay Malabry (France); GDF SUEZ, Pole CHENE, Centre de Recherche et d'Innovation Gaz et Energies Nouvelles, 93211 Saint-Denis la Plaine (France)

    2010-03-15

    A new modeling strategy called F-TACLES (Filtered Tabulated Chemistry for Large Eddy Simulation) is developed to introduce tabulated chemistry methods in Large Eddy Simulation (LES) of turbulent premixed combustion. The objective is to recover the correct laminar flame propagation speed of the filtered flame front when subgrid scale turbulence vanishes as LES should tend toward Direct Numerical Simulation (DNS). The filtered flame structure is mapped using 1-D filtered laminar premixed flames. Closure of the filtered progress variable and the energy balance equations are carefully addressed in a fully compressible formulation. The methodology is first applied to 1-D filtered laminar flames, showing the ability of the model to recover the laminar flame speed and the correct chemical structure when the flame wrinkling is completely resolved. The model is then extended to turbulent combustion regimes by including subgrid scale wrinkling effects in the flame front propagation. Finally, preliminary tests of LES in a 3-D turbulent premixed flame are performed. (author)

  9. Advanced concepts for controlled combustion in engines. Final report

    SciTech Connect (OSTI)

    Oppenheim, A.K.

    1991-12-15

    Studies carried out at the University of California, Berkeley, over a period of four years were concerned with fluid mechanical properties of turbulent pulsed jet plumes - systems that are of particular relevance to the initiation and control of combustion in engines. The eventual purpose of this program was to provide a rational background for a fundamental refinement of stratified charge diesel engines - the development of a combustion system where the formation of pollutants is minimized, fuel economy is maximized, while fuel tolerance is optimized. The results demonstrated that this goal is attainable by means of appropriate Pulsed Jet Combustion (PJC) generators. The exothermic process of combustion is executed thereby in the form of a fireball taking place in a stratified charge generated by turbulent plumes of a PJC system.

  10. Numerical investigation of high-pressure combustion in rocket engines using Flamelet/Progress-variable models

    E-Print Network [OSTI]

    Coclite, A; De Palma, P; Pascazio, G

    2015-01-01

    The present paper deals with the numerical study of high pressure LOx/H2 or LOx/hydrocarbon combustion for propulsion systems. The present research effort is driven by the continued interest in achieving low cost, reliable access to space and more recently, by the renewed interest in hypersonic transportation systems capable of reducing time-to-destination. Moreover, combustion at high pressure has been assumed as a key issue to achieve better propulsive performance and lower environmental impact, as long as the replacement of hydrogen with a hydrocarbon, to reduce the costs related to ground operations and increase flexibility. The current work provides a model for the numerical simulation of high- pressure turbulent combustion employing detailed chemistry description, embedded in a RANS equations solver with a Low Reynolds number k-omega turbulence model. The model used to study such a combustion phenomenon is an extension of the standard flamelet-progress-variable (FPV) turbulent combustion model combined ...

  11. Partially Premixed Combustion | Department of Energy

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

    Partially Premixed Combustion Partially Premixed Combustion Published materials on partial premixed combustion (PPC) combined with Volvo's own combustion research provides...

  12. Can we characterize turbulence in premixed flames?

    SciTech Connect (OSTI)

    Lipatnikov, A.N. [Department of Applied Mechanics, Chalmers University of Technology, Gothenburg, 412 96 (Sweden)

    2009-06-15

    Modeling of premixed turbulent combustion involves averaging reaction rates in turbulent flows. The focus of most approaches to resolving this problem has been placed on determining the dependence of the mean rate w of product creation on the laminar flame speed S{sub L}, the rms turbulence velocity u', etc. The goal of the present work is to draw attention to another issue: May the input quantity u{sup '} for a model of w= w(u'/S{sub L},..) be considered to be known? The point is that heat release substantially affects turbulence and, hence, turbulence characteristics in premixed flames should be modeled. However, standard moment methods for numerically simulating turbulent flows do not allow us to evaluate the true turbulence characteristics in a flame. For instance, the Reynolds stresses in premixed flames are affected not only by turbulence itself, but also by velocity jump across flamelets. A common way to resolving this problem consists of considering the Reynolds stresses conditioned on unburned (or burned) mixture to be the true turbulence characteristics. In the present paper, this widely accepted but never proved hypothesis is put into question, first, by considering simple model constant-density problems (flame motion in an oscillating one-dimensional laminar flow; flame stabilized in a periodic shear, one-dimensional, laminar flow; turbulent mixing). In all the cases, the magnitude of velocity fluctuations, calculated using the conditioned Reynolds stresses, is affected by the intermittency of reactants and products and, hence, is not the true rms velocity. Second, the above claim is further supported by comparing balance equations for the mean and conditioned Reynolds stresses. The conditioned Reynolds stresses do not characterize the true turbulence in flames, because conditional averaging cuts off flow regions characterized by either high or low velocities. (author)

  13. Combustion chemistry

    SciTech Connect (OSTI)

    Brown, N.J. [Lawrence Berkeley Laboratory, CA (United States)

    1993-12-01

    This research is concerned with the development and use of sensitivity analysis tools to probe the response of dependent variables to model input variables. Sensitivity analysis is important at all levels of combustion modeling. This group`s research continues to be focused on elucidating the interrelationship between features in the underlying potential energy surface (obtained from ab initio quantum chemistry calculations) and their responses in the quantum dynamics, e.g., reactive transition probabilities, cross sections, and thermal rate coefficients. The goals of this research are: (i) to provide feedback information to quantum chemists in their potential surface refinement efforts, and (ii) to gain a better understanding of how various regions in the potential influence the dynamics. These investigations are carried out with the methodology of quantum functional sensitivity analysis (QFSA).

  14. Rotary internal combustion engine

    SciTech Connect (OSTI)

    Le, L.K.

    1990-11-20

    This patent describes an internal combustion engine comprising; a rotary compressor mechanism; a rotary expander mechanism; and combustion chamber means disposed between the compressor mechanism and the expander mechanism, whereby compressed air is delivered to the combustion chamber through the compressor discharge port, and pressurized gas is delivered from the combustion chamber into the expander mechanism through the pressurized gas intake port.

  15. Direct numerical simulation of turbulent reacting flows

    SciTech Connect (OSTI)

    Chen, J.H. [Sandia National Laboratories, Livermore, CA (United States)

    1993-12-01

    The development of turbulent combustion models that reflect some of the most important characteristics of turbulent reacting flows requires knowledge about the behavior of key quantities in well defined combustion regimes. In turbulent flames, the coupling between the turbulence and the chemistry is so strong in certain regimes that is is very difficult to isolate the role played by one individual phenomenon. Direct numerical simulation (DNS) is an extremely useful tool to study in detail the turbulence-chemistry interactions in certain well defined regimes. Globally, non-premixed flames are controlled by two limiting cases: the fast chemistry limit, where the turbulent fluctuations. In between these two limits, finite-rate chemical effects are important and the turbulence interacts strongly with the chemical processes. This regime is important because industrial burners operate in regimes in which, locally the flame undergoes extinction, or is at least in some nonequilibrium condition. Furthermore, these nonequilibrium conditions strongly influence the production of pollutants. To quantify the finite-rate chemistry effect, direct numerical simulations are performed to study the interaction between an initially laminar non-premixed flame and a three-dimensional field of homogeneous isotropic decaying turbulence. Emphasis is placed on the dynamics of extinction and on transient effects on the fine scale mixing process. Differential molecular diffusion among species is also examined with this approach, both for nonreacting and reacting situations. To address the problem of large-scale mixing and to examine the effects of mean shear, efforts are underway to perform large eddy simulations of round three-dimensional jets.

  16. COAL DESULFURIZATION PRIOR TO COMBUSTION

    E-Print Network [OSTI]

    Wrathall, J.

    2013-01-01

    90e COAL DESULFURIZATION PRIOR TO COMBUSTION J. Wrathall, T.of coal during combustion. The process involves the additionCOAL DESULFURIZATION PRIOR TO COMBUSTION Lawrence Berkeley

  17. Transport Properties for Combustion Modeling

    E-Print Network [OSTI]

    Brown, N.J.

    2010-01-01

    a critical role in combustion processes just as chemicalparameters are essential for combustion modeling; molecularwith Application to Combustion. Transport Theor Stat 2003;

  18. Combustion 2000

    SciTech Connect (OSTI)

    A. Levasseur; S. Goodstine; J. Ruby; M. Nawaz; C. Senior; F. Robson; S. Lehman; W. Blecher; W. Fugard; A. Rao; A. Sarofim; P. Smith; D. Pershing; E. Eddings; M. Cremer; J. Hurley; G. Weber; M. Jones; M. Collings; D. Hajicek; A. Henderson; P. Klevan; D. Seery; B. Knight; R. Lessard; J. Sangiovanni; A. Dennis; C. Bird; W. Sutton; N. Bornstein; F. Cogswell; C. Randino; S. Gale; Mike Heap

    2001-06-30

    This report is a presentation of work carried out on Phase II of the HIPPS program under DOE contract DE-AC22-95PC95144 from June 1995 to March 2001. The objective of this report is to emphasize the results and achievements of the program and not to archive every detail of the past six years of effort. These details are already available in the twenty-two quarterly reports previously submitted to DOE and in the final report from Phase I. The report is divided into three major foci, indicative of the three operational groupings of the program as it evolved, was restructured, or overtaken by events. In each of these areas, the results exceeded DOE goals and expectations. HIPPS Systems and Cycles (including thermodynamic cycles, power cycle alternatives, baseline plant costs and new opportunities) HITAF Components and Designs (including design of heat exchangers, materials, ash management and combustor design) Testing Program for Radiative and Convective Air Heaters (including the design and construction of the test furnace and the results of the tests) There are several topics that were part of the original program but whose importance was diminished when the contract was significantly modified. The elimination of the subsystem testing and the Phase III demonstration lessened the relevance of subtasks related to these efforts. For example, the cross flow mixing study, the CFD modeling of the convective air heater and the power island analysis are important to a commercial plant design but not to the R&D product contained in this report. These topics are of course, discussed in the quarterly reports under this contract. The DOE goal for the High Performance Power Plant System ( HIPPS ) is high thermodynamic efficiency and significantly reduced emissions. Specifically, the goal is a 300 MWe plant with > 47% (HHV) overall efficiency and {le} 0.1 NSPS emissions. This plant must fire at least 65% coal with the balance being made up by a premium fuel such as natural gas. To achieve these objectives requires a change from complete reliance of coal-fired systems on steam turbines (Rankine cycles) and moving forward to a combined cycle utilizing gas turbines (Brayton cycles) which offer the possibility of significantly greater efficiency. This is because gas turbine cycles operate at temperatures well beyond current steam cycles, allowing the working fluid (air) temperature to more closely approach that of the major energy source, the combustion of coal. In fact, a good figure of merit for a HIPPS design is just how much of the enthalpy from coal combustion is used by the gas turbine. The efficiency of a power cycle varies directly with the temperature of the working fluid and for contemporary gas turbines the optimal turbine inlet temperature is in the range of 2300-2500 F (1260-1371 C). These temperatures are beyond the working range of currently available alloys and are also in the range of the ash fusion temperature of most coals. These two sets of physical properties combine to produce the major engineering challenges for a HIPPS design. The UTRC team developed a design hierarchy to impose more rigor in our approach. Once the size of the plant had been determined by the choice of gas turbine and the matching steam turbine, the design process of the High Temperature Advanced Furnace (HITAF) moved ineluctably to a down-fired, slagging configuration. This design was based on two air heaters: one a high temperature slagging Radiative Air Heater (RAH) and a lower temperature, dry ash Convective Air Heater (CAH). The specific details of the air heaters are arrived at by an iterative sequence in the following order:-Starting from the overall Cycle requirements which set the limits for the combustion and heat transfer analysis-The available enthalpy determined the range of materials, ceramics or alloys, which could tolerate the temperatures-Structural Analysis of the designs proved to be the major limitation-Finally the commercialization issues of fabrication and reliability, availability and maintenance. The program that has s

  19. US National Technical Meeting of the Combustion Institute

    E-Print Network [OSTI]

    Raman, Venkat

    -diffusion hypothesis [15]. The term G accounts for the change in the PDF due to spray evaporation. G() = ( - ) W. (4 of Turbulent Spray Combustion C. Heye, H. Koo and V. Raman1 1 Department of Aerospace Engineering and Engineering Mechanics, The University of Texas at Austin, Austin, Texas 78712, USA Direct numerical simulation

  20. Solution Combustion Synthesis Impregnated Layer Combustion Synthesis is a Novel

    E-Print Network [OSTI]

    Mukasyan, Alexander

    Solution Combustion Synthesis Impregnated Layer Combustion Synthesis is a Novel Methodology Engineering University of Notre Dame University of Notre Dame #12;Outline: Overview of combustion synthesis Reaction system Combustion front analaysis Theoretical model results Conclusions Acknowledgements #12

  1. Numerical simulation of Lewis number effects on lean premixed turbulent flames

    E-Print Network [OSTI]

    Bell, John B.

    turbulent flames for lean hydrogen, propane and methane mixtures in two dimensions. Each simulation is broken indicating local extinction. Keywords: turbulent premixed combustion, low Mach number flow for propane, methane and hydrogen using de- tailed chemistry and transport, corresponding to Le > 1, Le 1

  2. Effect of chemical reactions on decaying isotropic turbulence M. Pino Martin and Graham V. Candler

    E-Print Network [OSTI]

    Martín, Pino

    Effect of chemical reactions on decaying isotropic turbulence M. Pino Marti´n and Graham V. Candler combustion flows, however the interaction between turbulent motion and the chemical reactions that occur. In hypersonic flows the dominant chemical reactions are the dissociation and recombination of nitrogen

  3. COMBUSTION RESEARCH - FY-1979

    E-Print Network [OSTI]

    ,

    2012-01-01

    relative to combustion in the single-pulse engine. FOOTNOTEto engine combustion have been conducted in a single- pulsecombustion in engines conducted in our laboratory by the use of the single pulse

  4. COMBUSTION RESEARCH - FY-1979

    E-Print Network [OSTI]

    ,

    2012-01-01

    boundary layer for propane/air combustion on a platinumDuring FY 1979 the combustion of lean propane/ air mixturescombustion characteristics of a two-dimensional flow of premixed propane/

  5. Numerical Simulation of a Premixed Turbulent V-Flame1 , M. S. Day, J. F. Grcar, M. J. Lijewski, M. Johnson, R. K. Cheng and I. G. Shepherd

    E-Print Network [OSTI]

    Bell, John B.

    and Dufour effects, and radiative heat transfer, and assume a mixture-averaged model for differential species methods, low Mach number flows Turbulent premixed combustion is a major active research topic without introducing models for turbulence or turbulence chemistry interaction. We outline the numerical

  6. The interaction of high-speed turbulence with flames: Global properties and internal flame structure

    SciTech Connect (OSTI)

    Poludnenko, A.Y.; Oran, E.S. [Laboratory for Computational Physics and Fluid Dynamics, Naval Research Laboratory, Washington, DC 20375 (United States)

    2010-05-15

    We study the dynamics and properties of a turbulent flame, formed in the presence of subsonic, high-speed, homogeneous, isotropic Kolmogorov-type turbulence in an unconfined system. Direct numerical simulations are performed with Athena-RFX, a massively parallel, fully compressible, high-order, dimensionally unsplit, reactive flow code. A simplified reaction-diffusion model represents a stoichiometric H{sub 2}-air mixture. The system being modeled represents turbulent combustion with the Damkoehler number Da=0.05 and with the turbulent velocity at the energy injection scale 30 times larger than the laminar flame speed. The simulations show that flame interaction with high-speed turbulence forms a steadily propagating turbulent flame with a flame brush width approximately twice the energy injection scale and a speed four times the laminar flame speed. A method for reconstructing the internal flame structure is described and used to show that the turbulent flame consists of tightly folded flamelets. The reaction zone structure of these is virtually identical to that of the planar laminar flame, while the preheat zone is broadened by approximately a factor of two. Consequently, the system evolution represents turbulent combustion in the thin reaction zone regime. The turbulent cascade fails to penetrate the internal flame structure, and thus the action of small-scale turbulence is suppressed throughout most of the flame. Finally, our results suggest that for stoichiometric H{sub 2}-air mixtures, any substantial flame broadening by the action of turbulence cannot be expected in all subsonic regimes. (author)

  7. MAE Seminar Series Combustion Chemistry and Laser

    E-Print Network [OSTI]

    Krovi, Venkat

    to macroscale fluid motion). In this seminar, the results of experimental efforts are presented which: 1 for the development of kinetic models used to describe the combustion of liquid hydrocarbon fuels (e.g., jet fuels, Aerospace, and Nuclear Engineering at Rensselaer Polytechnic Institute, where he is currently an Assistant

  8. Is combustion of plastics desirable?

    SciTech Connect (OSTI)

    Piasecki, B.; Rainey, D.; Fletcher, K.

    1998-07-01

    Managing waste will always entail some tradeoffs. All of the three options--recycling, landfilling and combustion--have some disadvantages. Even landfilling, which produces no emissions, fails to take advantage of the energy value inherent in plastic. Waste combustion, on the other hand, recovers the energy in plastic materials and reduces the volume of disposed solid waste by up to 90% of its initial preburn volumes. However, this management option generates emissions and produces an ash residue that must be managed. As demonstrated by recent test burns, improvements in combustion and air-pollution-control technology have dramatically reduced the health risks from emissions and ash. Recent studies have shown that plastics--in quantities even higher than those normally found in municipal solid waste--do not adversely affect levels of emissions or the quality of ash from waste-to-energy facilities. In addition, waste-to-energy facilities may be a relatively economical source of fuel, and may be a more economic solution to waste management than the other available options. A waste-to-energy plant generally produces electricity that is sold to the electric utilities for approximately six cents per kilowatt-hour, a rate that is competitive with those offered by nuclear power plants and power plants that generate energy by burning fossil fuels.

  9. Supersonic combustion engine and method of combustion initiation and distribution

    SciTech Connect (OSTI)

    Stickler, D.B.; Ballantyne, A.; Kyuman Jeong.

    1993-06-29

    A supersonic combustion ramjet engine having a combustor with a combustion zone intended to channel gas flow at relatively high speed therethrough, the engine comprising: means for substantially continuously supplying fuel into the combustion zone; and means for substantially instantaneously igniting a volume of fuel in the combustion zone for providing a spatially controlled combustion distribution, the igniting means having means for providing a diffuse discharge of energy into the volume, the volume extending across a substantially complete cross-sectional area of the combustion zone, the means for discharging energy being capable of generating free radicals within the volume of reactive fuel in the combustion zone such that fuel in the volume can initiate a controlled relatively rapid combustion of fuel in the combustion zone whereby combustion distribution in relatively high speed gas flows through the combustion zone can be initiated and controlled without dependence upon a flame holder or relatively high local static temperature in the combustion zone.

  10. Combustion Byproducts Recycling Consortium

    SciTech Connect (OSTI)

    Paul Ziemkiewicz; Tamara Vandivort; Debra Pflughoeft-Hassett; Y. Paul Chugh; James Hower

    2008-08-31

    Ashlines: To promote and support the commercially viable and environmentally sound recycling of coal combustion byproducts for productive uses through scientific research, development, and field testing.

  11. Low NOx combustion

    DOE Patents [OSTI]

    Kobayashi; Hisashi (Putnam Valley, NY), Bool, III; Lawrence E. (Aurora, NY)

    2007-06-05

    Combustion of hydrocarbon liquids and solids is achieved with less formation of NOx by feeding a small amount of oxygen into the fuel stream.

  12. Non-premixed flame-turbulence interaction in compressible turbulent flow

    SciTech Connect (OSTI)

    Livescu, D. (Daniel); Madnia, C. K.

    2002-01-01

    Nonpremixed turbulent reacting flows are intrinsically difficult to model due to the strong coupling between turbulent motions and reaction. The large amount of heat released by a typical hydrocarbon flame leads to significant modifications of the thermodynamic variables and the molecular transport coefficients and thus alters the fluid dynamics. Additionally, in nonpremixed combustion, the flame has a complex spatial structure. Localized expansions and contractions occur, enhancing the dilatational motions. Therefore, the compressibility of the flow and the heat release are intimately related. However, fundamental studies of the role of compressibility on the scalar mixing and reaction are scarce. In this paper they present results concerning the fundamental aspects of the interaction between non-premixed flame and compressible turbulence.

  13. COMBUSTION SOURCES OF NITROGEN COMPOUNDS

    E-Print Network [OSTI]

    Brown, Nancy J.

    2011-01-01

    Rasmussen, R.A. (1976). Combustion as a source of nitrousx control for stationary combustion sources. Prog. Energy,CA, March 3-4, 1977 COMBUSTION SOURCES OF NITROGEN COMPOUNDS

  14. Large eddy simulation and experimental measurements of the near-field of a large turbulent helium plume

    E-Print Network [OSTI]

    DesJardin, Paul E.

    diameters from the fuel source are of greatest interest since the bulk of the combustion takes place a fire requires accurate modeling of turbulent, combustion, and thermal radiation processes. A full description of all these processes has proven to be an enormous challenge for CFD modeling. The approach

  15. Fifteenth combustion research conference

    SciTech Connect (OSTI)

    NONE

    1993-06-01

    The BES research efforts cover chemical reaction theory, experimental dynamics and spectroscopy, thermodynamics of combustion intermediates, chemical kinetics, reaction mechanisms, combustion diagnostics, and fluid dynamics and chemically reacting flows. 98 papers and abstracts are included. Separate abstracts were prepared for the papers.

  16. One-dimensional turbulence model simulations of autoignition of hydrogen/carbon monoxide fuel mixtures in a turbulent jet

    SciTech Connect (OSTI)

    Gupta, Kamlesh G.; Echekki, Tarek [Department of Mechanical and Aerospace Engineering, North Carolina State University, NC (United States)

    2011-02-15

    The autoignition of hydrogen/carbon monoxide in a turbulent jet with preheated co-flow air is studied using the one-dimensional turbulence (ODT) model. The simulations are performed at atmospheric pressure based on varying the jet Reynolds number and the oxidizer preheat temperature for two compositions corresponding to varying the ratios of H{sub 2} and CO in the fuel stream. Moreover, simulations for homogeneous autoignition are implemented for similar mixture conditions for comparison with the turbulent jet results. The results identify the key effects of differential diffusion and turbulence on the onset and eventual progress of autoignition in the turbulent jets. The differential diffusion of hydrogen fuels results in a reduction of the ignition delay relative to similar conditions of homogeneous autoignition. Turbulence may play an important role in delaying ignition at high-turbulence conditions, a process countered by the differential diffusion of hydrogen relative to carbon monoxide; however, when ignition is established, turbulence enhances the overall rates of combustion of the non-premixed flame downstream of the ignition point. (author)

  17. Optimized Algorithms Boost Combustion Research

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

    Optimized Algorithms Boost Combustion Research Optimized Algorithms Boost Combustion Research Methane Flame Simulations Run 6x Faster on NERSC's Hopper Supercomputer November 25,...

  18. ALS Evidence Confirms Combustion Theory

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

    Evidence Confirms Combustion Theory ALS Evidence Confirms Combustion Theory Print Wednesday, 22 October 2014 11:43 Researchers recently uncovered the first step in the process that...

  19. 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.

  20. Quantum Gravity and Turbulence

    E-Print Network [OSTI]

    Vishnu Jejjala; Djordje Minic; Y. Jack Ng; Chia-Hsiung Tze

    2010-05-18

    We apply recent advances in quantum gravity to the problem of turbulence. Adopting the AdS/CFT approach we propose a string theory of turbulence that explains the Kolmogorov scaling in 3+1 dimensions and the Kraichnan and Kolmogorov scalings in 2+1 dimensions. In the gravitational context, turbulence is intimately related to the properties of spacetime, or quantum, foam.

  1. COMBUSTION RESEARCH - FY-1979

    E-Print Network [OSTI]

    ,

    2012-01-01

    United States Nuclear Regulatory Commission, 1-Jashington,United States Nuclear Regulatory Commission, Washingtonby the U.S. Nuclear Regulatory Commission through Sandia

  2. Fuels and Combustion Strategies for High-Efficiency Clean-Combustion...

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

    Combustion Strategies for High-Efficiency Clean-Combustion Engines Fuels and Combustion Strategies for High-Efficiency Clean-Combustion Engines 2012 DOE Hydrogen and Fuel Cells...

  3. Combustion and Magnetohydrodynamic Processes in Advanced Pulse Detonation Rocket Engines

    E-Print Network [OSTI]

    Cole, Lord Kahil

    2012-01-01

    CombustionEquations . . . . . . . . . . Combustion and Ionizationpulsating detonations. Combustion Theory and Modeling, 9:

  4. Theoretical studies on hydrogen ignition and droplet combustion

    E-Print Network [OSTI]

    Del Álamo, Gonzalo

    2006-01-01

    1.2 Droplet Combustion . . . . . . . . . . . . .Combustion . . . . . . . . . . . . . . . . . . . . . . . . . .Lewis, B. and von Elbe, G. Combustion, Flames and Explosions

  5. Oxy-coal Combustion Studies

    SciTech Connect (OSTI)

    J. Wendt; E. Eddings; J. Lighty; T. Ring; P. Smith; J. Thornock; Y. Jia, W. Morris; J. Pedel; D. Rezeai; L. Wang; J. Zhang; K. Kelly

    2012-01-01

    The objective of this project is to move toward the development of a predictive capability with quantified uncertainty bounds for pilot-scale, single-burner, oxy-coal operation. This validation research brings together multi-scale experimental measurements and computer simulations. The combination of simulation development and validation experiments is designed to lead to predictive tools for the performance of existing air fired pulverized coal boilers that have been retrofitted to various oxy-firing configurations. In addition, this report also describes novel research results related to oxy-combustion in circulating fluidized beds. For pulverized coal combustion configurations, particular attention is focused on the effect of oxy-firing on ignition and coal-flame stability, and on the subsequent partitioning mechanisms of the ash aerosol. To these ends, the project has focused on the following: â?¢ The development of reliable Large Eddy Simulations (LES) of oxy-coal flames using the Direct Quadrature Method of Moments (DQMOM) (Subtask 3.1). The simulations were validated for both non-reacting particle-laden jets and oxy-coal flames. â?¢ The modifications of an existing oxy-coal combustor to allow operation with high levels of input oxygen to enable in-situ laser diagnostic measurements as well as the development of strategies for directed oxygen injection (Subtask 3.2). Flame stability was quantified for various burner configurations. One configuration that was explored was to inject all the oxygen as a pure gas within an annular oxygen lance, with burner aerodynamics controlling the subsequent mixing. â?¢ The development of Particle Image Velocimetry (PIV) for identification of velocity fields in turbulent oxy-coal flames in order to provide high-fidelity data for the validation of oxy-coal simulation models (Subtask 3.3). Initial efforts utilized a laboratory diffusion flame, first using gas-fuel and later a pulverized-coal flame to ensure the methodology was properly implemented and that all necessary data and image-processing techniques were fully developed. Success at this stage of development led to application of the diagnostics in a large-scale oxy-fuel combustor (OFC). â?¢ The impact of oxy-coal-fired vs. air-fired environments on SO{sub x} (SO{sub 2}, SO{sub 3}) emissions during coal combustion in a pilot-scale circulating fluidized-bed (CFB) (Subtask 3.4). Profiles of species concentration and temperature were obtained for both conditions, and profiles of temperature over a wide range of O{sub 2} concentration were studied for oxy-firing conditions. The effect of limestone addition on SO{sub 2} and SO{sub 3} emissions were also examined for both air- and oxy- firing conditions. â?¢ The investigation of O{sub 2}/CO{sub 2} and O{sub 2}/N{sub 2} environments on SO{sub 2 emissions during coal combustion in a bench-scale single-particle fluidized-bed reactor (Subtask 3.5). Moreover, the sulfation mechanisms of limestone in O{sub 2}/CO{sub 2} and O{sub 2}/N{sub 2} environments were studied, and a generalized gassolid and diffusion-reaction single-particle model was developed to study the effect of major operating variables. â?¢ The investigation of the effect of oxy-coal combustion on ash formation, particle size distributions (PSD), and size-segregated elemental composition in a drop-tube furnace and the 100 kW OFC (Subtask 3.6). In particular, the effect of coal type and flue gas recycle (FGR, OFC only) was investigated.

  6. Stratified cross combustion engine

    SciTech Connect (OSTI)

    Rhoads, J.L.

    1981-06-23

    A piston engine is provided in which adjacent cylinder pairs share a common combustion chamber and the pistons are mounted to reciprocate substantially in phase, one of the pistons in each piston pair receiving a rich mixture which is ignited by a sparkplug in that cylinder, with the other cylinder in the cylinder pair being passive in its preferred form, and receiving through a separate intake valve either pure air or a leaner mixture into which the combusted richer mixture pours, insuring that the greatest combustion possible resulting in the greatest percentage of carbon dioxide formation as opposed to carbon monoxide is created.

  7. Dry low combustion system with means for eliminating combustion noise

    DOE Patents [OSTI]

    Verdouw, Albert J.; Smith, Duane; McCormick, Keith; Razdan, Mohan K.

    2004-02-17

    A combustion system including a plurality of axially staged tubular premixers to control emissions and minimize combustion noise. The combustion system includes a radial inflow premixer that delivers the combustion mixture across a contoured dome into the combustion chamber. The axially staged premixers having a twist mixing apparatus to rotate the fluid flow and cause improved mixing without causing flow recirculation that could lead to pre-ignition or flashback.

  8. Sandia Combustion Research: Technical review

    SciTech Connect (OSTI)

    1995-07-01

    This report contains reports from research programs conducted at the Sandia Combustion Research Facility. Research is presented under the following topics: laser based diagnostics; combustion chemistry; reacting flow; combustion in engines and commercial burners; coal combustion; and industrial processing. Individual projects were processed separately for entry onto the DOE databases.

  9. Optical monitor for observing turbulent flow

    DOE Patents [OSTI]

    Albrecht, Georg F. (Livermore, CA); Moore, Thomas R. (Rochester, NY)

    1992-01-01

    The present invention provides an apparatus and method for non-invasively monitoring turbulent fluid flows including anisotropic flows. The present invention uses an optical technique to filter out the rays travelling in a straight line, while transmitting rays with turbulence induced fluctuations in time. The output is two dimensional, and can provide data regarding the spectral intensity distribution, or a view of the turbulence in real time. The optical monitor of the present invention comprises a laser that produces a coherent output beam that is directed through a fluid flow, which phase-modulates the beam. The beam is applied to a temporal filter that filters out the rays in the beam that are straight, while substantially transmitting the fluctuating, turbulence-induced rays. The temporal filter includes a lens and a photorefractive crystal such as BaTiO.sub.3 that is positioned in the converging section of the beam near the focal plane. An imaging system is used to observe the filtered beam. The imaging system may take a photograph, or it may include a real time camera that is connected to a computer. The present invention may be used for many purposes including research and design in aeronautics, hydrodynamics, and combustion.

  10. Pressure-gain combustion. Part 1: Model development

    SciTech Connect (OSTI)

    Narayanaswami, L. [Embry-Riddle Aeronautical Univ., Daytona Beach, FL (United States); Richards, G.A. [Dept. of Energy, Morgantown, WV (United States). Morgantown Energy Technology Center

    1996-07-01

    A model for aerodynamically valved pulse combustion is presented. Particular emphasis is placed on using the model equations to identify characteristic length and time scales relevant to the design of pressure-gain combustors for gas turbine applications. The model is a control volume description of conservation laws for several regions of the pulse combustor. Combustion is modeled as a bimolecular reaction. Mixing between the fresh charge and the combustion products is modeled using a turbulent eddy time estimated from the combustor geometry and flow conditions. The model equations identify two characteristic lengths, which should be held constant during combustor scaleup, as well as certain exceptions to this approach. The effect of ambient operating pressure and inlet air temperature is also discussed.

  11. Advanced Combustion FAQs

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

    The advantage of these advanced combustion systems is that the high concentration of CO2 in the flue gas reduces the cost and improves the performance of the CO2 capture...

  12. Combustion Air Control 

    E-Print Network [OSTI]

    Hughart, C. L.

    1979-01-01

    to 100%. If the air and fuel controls are on automatic but the flue gas oxygen content cannot be lowered to 4% oxygen without the boiler smoking, burner problems may be suspected. The trouble may be traced to dirty or improperly assembled oil guns..., combustion air distribution problems, vaporizing steam control problems, oil viscosity, or flow control problems. It is very important to have all oil guns operating properly before proceeding with a combustion test. The minimum stack gas oxygen level you...

  13. Evaluation of a reduced mechanism for turbulent premixed combustion

    E-Print Network [OSTI]

    Nikolaou, Zacharias M.; Swaminathan, Nedunchezhian; Chen, Jyh-Yuan

    2014-07-21

    stricter, due to increasing levels of CO2 in the atmosphere. In light of these developments, low calo- rific value fuels such as Coke Oven Gas (COG), Blast Furnace Gas (BFG), and those coming from bio-gasifiers, are becoming increas- ingly popular... as alternative fuels for power generation using indus- trial gas-turbines [1]. These are typically multi-component fuels, involving CO; H2; H2O; CH4; CO2; O2 and N2, with their composi- reaction set usually involves more than hundreds of reactions and tens...

  14. Paper # B38 Topic: Turbulent Flames US Combustion Meeting

    E-Print Network [OSTI]

    Pitsch, Heinz

    is an increasingly important problem. Jet engines in par- ticular produce sound levels that are not only a nuisance-eddy simulation M. Ihme1 , H. Pitsch1 , and M. Kaltenbacher2 1 Department of Mechanical Engineering, Stanford, but may also impair hearing. The noise emitted by such engines is generated by different sources

  15. Sandia Energy - The CRF's Turbulent Combustion Lab (TCL) Captures the

    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 AdministrationRobust, High-Throughput AnalysisSinkholeCapabilities General overview of theBrain: Key To

  16. Pressure non-uniformity and mixing characteristics in stratified-charge rotary engine combustion

    SciTech Connect (OSTI)

    Abraham, J.; Wey, M.J.; Bracco, F.V.

    1988-01-01

    Stratified-charge combustion in rotary engines was studied using a three-dimensional model to compute intake, compression, liquid fuel injection, combustion, expansion, and exhaust. The model was applied to two engines of different displacement and at seven operating conditions. Good agreement is found between the measured pressure and the results of previous studies. The main feature of the combustion flowfield in the two engines, the slow and nonuniform mixing of fuel and air which leads to long and incomplete combustion, is attributed at least in part to low turbulent diffusivity within the rotor pocket. The TDC diffusivity in this type of rotary engine is shown to be lower than in corresponding reciprocating engines primarily because of the longer time between intake and TDC. The model also explains pressure nonuniformities that have been experimentally observed within the combustion chamber around TDC. The nonuniformity is due to the large fluid acceleration caused by the motion of the rotor. 34 references.

  17. Sandia Energy - Pressurized Combustion and Gasification

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

    oxy-fuel combustion. However, properly designing new pressurized combustion burners and boilers requires accurate data on coal devolatilization and combustion rates...

  18. Development of Advanced Combustion Technologies for Increased...

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

    Investigation of fuel effects on low-temperature combustion, particularly HCCI PCCI combustion deer09gehrke.pdf More Documents & Publications The Role of Advanced Combustion in...

  19. Engine Combustion Network (ECN): Global sensitivity analysis...

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

    Engine Combustion Network (ECN): Global sensitivity analysis of Spray A for different combustion vessels Title Engine Combustion Network (ECN): Global sensitivity analysis of Spray...

  20. Vehicle Technologies Office: 2014 Advanced Combustion Engine...

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

    2014 Advanced Combustion Engine Annual Progress Report Vehicle Technologies Office: 2014 Advanced Combustion Engine Annual Progress Report The Advanced Combustion Engine research...

  1. Constant Volume During Combustion | Department of Energy

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

    Constant Volume During Combustion Constant Volume During Combustion This presentation covers constant volume during combustion and discusses how it can alter the kinematics of...

  2. COMBUSTION-GENERATED INDOOR AIR POLLUTION

    E-Print Network [OSTI]

    Hollowell, C.D.

    2011-01-01

    Pollutants from Indoor Combustion Sources: I. Field Measure-Characteristics in Two Stage Combustion, paper presented atInternational) on Combustion, August, 1974, Tokyo, Japan. 8

  3. Vehicle Technologies Office: 2014 Advanced Combustion Engine...

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

    Advanced Combustion Engine Annual Progress Report Vehicle Technologies Office: 2014 Advanced Combustion Engine Annual Progress Report The Advanced Combustion Engine research and...

  4. COMBUSTION-GENERATED INDOOR AIR POLLUTION

    E-Print Network [OSTI]

    Hollowell, C.D.

    2011-01-01

    Ext. 6782 Combustion -Generated Indoor Air Pollution Craigcontrol of air pollution from indoor combustion sources. Ifocused on combustion-generated indoor air pollution, namely

  5. Coal Combustion Products | Department of Energy

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

    Coal Combustion Products Coal Combustion Products Coal combustion products (CCPs) are solid materials produced when coal is burned to generate electricity. Since coal provides the...

  6. Rotary internal combustion engine

    SciTech Connect (OSTI)

    Murray, J.L.

    1993-07-20

    A multi bank power plant is described comprising at least a first and a second rotary internal combustion engine connectable together in series, each of the engines comprising: a housing; a cam track internally disposed within the housing and adapted to receive a cam follower; an engine block disposed within the housing and rotatable about a central axis; an output shaft extending axially from each the engine block, each output shaft being coaxial with the other; means for coupling the output shafts together so that the output shafts rotate together in the same direction at the same speed; at least one radially arranged cylinder assembly on each block, each cylinder assembly including a cylinder having a longitudinal axis extending generally radially outwardly from the rotational axis of the block, the cylinder including means defining an end wall, a piston member disposed within the cylinder and adapted to reciprocate within the cylinder; a combustion chamber, means permitting periodic introduction of air and fuel into the combustion chamber, means for causing combustion of a compressed mixture of air and fuel within the combustion chamber, means permitting periodic exhaust of products of combustion of air and fuel from the combustion chamber, and means for imparting forces and motions of the piston within the cylinder to and from the cam track, the means comprising a cam follower operatively connected to the piston; wherein the cam track includes at least a first segment and at least a second segment thereof, the first segment having a generally positive slope wherein the segment has a generally increasing radial distance from the rotational axis of the engine block whereby as a piston moves outwardly in a cylinder on a power stroke while the cam follower is in radial register with the cam track segment, the reactive force of the respective cam follower against the cam track segment acts in a direction tending to impart rotation to the engine block.

  7. Turbulent AGN tori

    E-Print Network [OSTI]

    M. Schartmann; K. Meisenheimer; H. Klahr; M. Camenzind; S. Wolf; Th. Henning

    2008-08-05

    Recently, the MID-infrared Interferometric instrument (MIDI) at the VLTI has shown that dust tori in the two nearby Seyfert galaxies NGC 1068 and the Circinus galaxy are geometrically thick and can be well described by a thin, warm central disk, surrounded by a colder and fluffy torus component. By carrying out hydrodynamical simulations with the help of the TRAMP code (Klahr et al. 1999), we follow the evolution of a young nuclear star cluster in terms of discrete mass-loss and energy injection from stellar processes. This naturally leads to a filamentary large scale torus component, where cold gas is able to flow radially inwards. The filaments open out into a dense and very turbulent disk structure. In a post-processing step, we calculate observable quantities like spectral energy distributions or images with the help of the 3D radiative transfer code MC3D (Wolf 2003). Good agreement is found in comparisons with data due to the existence of almost dust-free lines of sight through the large scale component and the large column densities caused by the dense disk.

  8. Combustion chamber noise suppressor

    SciTech Connect (OSTI)

    Livingston, A.M.

    1986-08-19

    A combustion chamber is described for a hot fog generating machine comprising a hollow cylindrical combustion chamber shell having a closure plate at one end and outlet means at the opposite end for directing hot combustion gasses to a fogging nozzle, air inlet means disposed adjacent the outlet means, fuel inlet means and ignition means mounted in the closure plate and liner means disposed concentrically within the cylindrical combustion chamber for controlling the flow of air and combustion gasses within the shell. The liner means includes a liner base having a frustroconical configuration with the smaller diameter end thereof disposed in communication with the outlet means and with the larger diameter end thereof disposed in spaced relation to the shell, circumferentially spaced, longitudinally extending fins extending outwardly from the liner base intermediate the liner base and the shell, a cylindrical liner midsection having circumferentially spaced fins extending outwardly therefrom between the midsection and the shell with the fins supporting the midsection on the larger diameter end of the liner base.

  9. Fully Developed Turbulent Mixing in an Annular Sector

    SciTech Connect (OSTI)

    Lim, Hyun-Kyung; Zhou, Yijie; de Almeida, Valmor F; Glimm, James G

    2014-01-01

    We review recent progress on the characterization of turbulent mixing fluid flow and relate these ideas to high-speed, two-phase Couette flow with application to mixing in a centrifugal contactor. The general ideas are more broadly applicable and have been applied to the study of Rayleigh-Taylor and Richtmyer-Meshkov fluid mixing, combustion in the engine of a scram jet and the analysis of inertial confinement pellet simulations.

  10. Numerical Simulation of Premixed Turbulent Methane J. B. Bell, M. S. Day, A. S. Almgren, R. K. Cheng and I. G.

    E-Print Network [OSTI]

    Bell, John B.

    the interaction of a laminar flame with decaying isotropic turbulence. Early studies of this type using single, and assume a mixture model for species diffusion. The single-grid scheme that forms the basis for ourNumerical Simulation of Premixed Turbulent Methane Combustion J. B. Bell, M. S. Day, A. S. Almgren

  11. Combustible structural composites and methods of forming combustible structural composites

    DOE Patents [OSTI]

    Daniels, Michael A. (Idaho Falls, ID); Heaps, Ronald J. (Idaho Falls, ID); Steffler, Eric D (Idaho Falls, ID); Swank, William D. (Idaho Falls, ID)

    2011-08-30

    Combustible structural composites and methods of forming same are disclosed. In an embodiment, a combustible structural composite includes combustible material comprising a fuel metal and a metal oxide. The fuel metal is present in the combustible material at a weight ratio from 1:9 to 1:1 of the fuel metal to the metal oxide. The fuel metal and the metal oxide are capable of exothermically reacting upon application of energy at or above a threshold value to support self-sustaining combustion of the combustible material within the combustible structural composite. Structural-reinforcing fibers are present in the composite at a weight ratio from 1:20 to 10:1 of the structural-reinforcing fibers to the combustible material. Other embodiments and aspects are disclosed.

  12. Combustible structural composites and methods of forming combustible structural composites

    DOE Patents [OSTI]

    Daniels, Michael A.; Heaps, Ronald J.; Steffler, Eric D.; Swank, W. David

    2013-04-02

    Combustible structural composites and methods of forming same are disclosed. In an embodiment, a combustible structural composite includes combustible material comprising a fuel metal and a metal oxide. The fuel metal is present in the combustible material at a weight ratio from 1:9 to 1:1 of the fuel metal to the metal oxide. The fuel metal and the metal oxide are capable of exothermically reacting upon application of energy at or above a threshold value to support self-sustaining combustion of the combustible material within the combustible structural composite. Structural-reinforcing fibers are present in the composite at a weight ratio from 1:20 to 10:1 of the structural-reinforcing fibers to the combustible material. Other embodiments and aspects are disclosed.

  13. Internal combustion rotary engine

    SciTech Connect (OSTI)

    Chen, S.P.

    1993-08-24

    An internal combustion rotary engine is described comprising: an internal combustion chamber wherein a combustible fuel-air mixture is ignited for producing a driving gas flow; a central rotor having an outer surface in which at least one group of curved channels circumferentially-and-axially extending without radially extending through the central rotor; and at least one annular rotor each enclosing the central rotor having an inner surface in which a corresponding number of curved channels circumferentially-and-axially extending without radially extending through the annular rotor; when the curved channels in the central rotor communicate with the curved channels in the annular rotor, the driving gas flow circumferentially-and-axially passing between the outer surface of the central rotor and the inner surface of the annular rotor for rotating the central rotor and the annular rotor in opposite directions.

  14. Modeling of scalar dissipation rates in flamelet models for low temperature combustion engine simulations

    E-Print Network [OSTI]

    Gupta, Saurabh; Pal, Pinaki; Im, Hong G

    2014-01-01

    The flamelet approach offers a viable framework for combustion modeling of homogeneous charge compression ignition (HCCI) engines under stratified mixture conditions. Scalar dissipation rate acts as a key parameter in flamelet-based combustion models which connects the physical mixing space to the reactive space. The aim of this paper is to gain fundamental insights into turbulent mixing in low temperature combustion (LTC) engines and investigate the modeling of scalar dissipation rate. Three direct numerical simulation (DNS) test cases of two-dimensional turbulent auto-ignition of a hydrogen-air mixture with different correlations of temperature and mixture fraction are considered, which are representative of different ignition regimes. The existing models of mean and conditional scalar dissipation rates, and probability density functions (PDFs) of mixture fraction and total enthalpy are a priori validated against the DNS data.

  15. DNS of inhomogeneous reactants premixed combustion

    E-Print Network [OSTI]

    Lim, Kian Min

    2015-02-03

    of the combustion. This ushers in a new mode of combustion, called the inhomogeneous reactants premixed combustion. The present study investigates the effects of inhomogeneous reactants on premixed combustion, specifically on the interactions of an initially...

  16. Fossil turbulence and fossil turbulence waves can be dangerous

    E-Print Network [OSTI]

    Carl H Gibson

    2012-11-25

    Turbulence is defined as an eddy-like state of fluid motion where the inertial-vortex forces of the eddies are larger than any other forces that tend to damp the eddies out. By this definition, turbulence always cascades from small scales where vorticity is created to larger scales where turbulence fossilizes. Fossil turbulence is any perturbation in a hydrophysical field produced by turbulence that persists after the fluid is no longer turbulent at the scale of the perturbation. Fossil turbulence patterns and fossil turbulence waves preserve and propagate energy and information about previous turbulence. Ignorance of fossil turbulence properties can be dangerous. Examples include the Osama bin Laden helicopter crash and the Air France 447 Airbus crash, both unfairly blamed on the pilots. Observations support the proposed definitions, and suggest even direct numerical simulations of turbulence require caution.

  17. Thermal ignition combustion system

    DOE Patents [OSTI]

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

    1988-01-01

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

  18. Thermal ignition combustion system

    DOE Patents [OSTI]

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

    1988-04-19

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

  19. Pulse enhanced fluidized bed combustion

    SciTech Connect (OSTI)

    Mueller, B.

    1996-12-31

    Information is outlined on pulse enhanced fluidized bed combustion. The following topics are discussed: what is pulse enhanced fluidized bed combustion?; pulse combustors; pulsed atmospheric fluidized bed combustor (PAFBC); advantages of PAFBC; performance advantages; PAFBC facts; and PAFBC contact points.

  20. Nanoparticle Emissions from Internal Combustion Engines | Department...

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

    Nanoparticle Emissions from Internal Combustion Engines Nanoparticle Emissions from Internal Combustion Engines 2004 Diesel Engine Emissions Reduction (DEER) Conference...

  1. Enhancing Transportation Energy Security through Advanced Combustion...

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

    Transportation Energy Security through Advanced Combustion and Fuels Technologies Enhancing Transportation Energy Security through Advanced Combustion and Fuels Technologies 2005...

  2. Turbulent Nonpremixed Flames (TNF): Experimental Data Archives and Computational Submodels

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

    In the 1990s an international collaboration formed around a series of workshops that became known collectively as the International Workshop on Measurement and Computation of Turbulent Non-Premixed Flames (TNF). An online library, hosted by Sandia National Laboratory (California) was established that provides data sets and submodels or "mechanisms" for the study of turbulence-chemistry interactions in turbulent nonpremixed and partially premixed combustion. Data are organized by flame types: simple jet flames, piloted jet flames, bluff body flames, and swirl flames. These data sets provide a means for collaborative comparisons of both measured and simulated/modeled research results and also assist scientists in determining priorities for further research. More than 20 data sets or databases are available from this website, along with various downloadable files of chemical mechanisms. The website also provides an extensive bibliography and the proceedings of the workshops themselves from 1996 through 2012. Information continues to be added to this collection.

  3. Packed Bed Combustion: An Overview

    E-Print Network [OSTI]

    Hallett, William L.H.

    Packed Bed Combustion: An Overview William Hallett Dept. of Mechanical Engineering Université d'Ottawa - University of Ottawa #12;Packed Bed Combustion - University of Ottawa - CICS 2005 Introduction air fuel feedproducts xbed grate Packed Bed Combustion: fairly large particles of solid fuel on a grate, air supplied

  4. PhD Thesis: Control issues in oxy-fuel combustion

    E-Print Network [OSTI]

    Foss, Bjarne A.

    carbon intensive fuels, renewable energy sources, nuclear energy and combustion with CO2 capture. The use as it costs energy to capture the CO2. Thus it is important to maximize the eciency in such plants. One;#12;Summary Combustion of fossil fuels is the major energy source in todays society. While the use of fossil

  5. LES SOFTWARE FOR THE DESIGN OF LOW EMISSION COMBUSTION SYSTEMS FOR VISION 21 PLANTS

    SciTech Connect (OSTI)

    Clifford E. Smith; Steven M. Cannon; Virgil Adumitroaie; David L. Black; Karl V. Meredith

    2005-01-01

    In this project, an advanced computational software tool was developed for the design of low emission combustion systems required for Vision 21 clean energy plants. Vision 21 combustion systems, such as combustors for gas turbines, combustors for indirect fired cycles, furnaces and sequestrian-ready combustion systems, will require innovative low emission designs and low development costs if Vision 21 goals are to be realized. The simulation tool will greatly reduce the number of experimental tests; this is especially desirable for gas turbine combustor design since the cost of the high pressure testing is extremely costly. In addition, the software will stimulate new ideas, will provide the capability of assessing and adapting low-emission combustors to alternate fuels, and will greatly reduce the development time cycle of combustion systems. The revolutionary combustion simulation software is able to accurately simulate the highly transient nature of gaseous-fueled (e.g. natural gas, low BTU syngas, hydrogen, biogas etc.) turbulent combustion and assess innovative concepts needed for Vision 21 plants. In addition, the software is capable of analyzing liquid-fueled combustion systems since that capability was developed under a concurrent Air Force Small Business Innovative Research (SBIR) program. The complex physics of the reacting flow field are captured using 3D Large Eddy Simulation (LES) methods, in which large scale transient motion is resolved by time-accurate numerics, while the small scale motion is modeled using advanced subgrid turbulence and chemistry closures. In this way, LES combustion simulations can model many physical aspects that, until now, were impossible to predict with 3D steady-state Reynolds Averaged Navier-Stokes (RANS) analysis, i.e. very low NOx emissions, combustion instability (coupling of unsteady heat and acoustics), lean blowout, flashback, autoignition, etc. LES methods are becoming more and more practical by linking together tens to hundreds of PCs and performing parallel computations with fine grids (millions of cells). Such simulations, performed in a few weeks or less, provide a very cost-effective complement to experimental testing. In 5 years, these same calculations can be performed in 24 hours or less due to the expected increase of computing power and improved numerical techniques. This project was a four-year program. During the first year, the project included the development and implementation of improved chemistry (reduced GRI mechanism), subgrid turbulence (localized dynamic), and subgrid combustion-turbulence interaction (Linear Eddy) models into the CFD-ACE+ code. University expertise (Georgia Tech and University of California, Berkeley) was utilized to help develop and implement these advanced submodels into the unstructured, parallel CFD flow solver, CFD-ACE+. Efficient numerical algorithms that rely on in situ look-up tables or artificial neural networks were implemented for chemistry calculations. In the second year, the combustion LES software was evaluated and validated using experimental data from lab-scale and industrial test configurations. This code testing (i.e., alpha testing) was performed by CFD Research Corporation's engineers. During the third year, six industrial and academic partners used the combustion LES code and exercised it on problems of their choice (i.e., beta testing). Final feedback and optimizations were then implemented into the final release (licensed) version of the combustion LES software to the general public. An additional one-year task was added for the fourth year of this program entitled, ''LES Simulations of SIMVAL Results''. For this task, CFDRC performed LES calculations of selected DoE SIMVAL cases, and compared predictions with measurements from NETL. In addition to comparisons with NOx and CO exit measurements, comparisons were made to measured pressure oscillations. Potential areas of improvement for combustion and turbulence models were identified. In conclusion, this program advanced the state-of-the-art in combustion LES an

  6. Turbulent premixed flame front dynamics and implications for limits of flamelet hypothesis

    E-Print Network [OSTI]

    Gülder, Ömer L.

    of methane­air and propane­air stabilized on a Bunsen-type burner were studied to investigate the dynamics. The equivalence ratio was varied from 0.6 (0.7 for propane) to stoichiometric. The flame front data were obtained The Combustion Institute. Published by Elsevier Inc. All rights reserved. Keywords: Turbulent premixed flames

  7. LES/PDF based modeling of sootturbulence interactions in turbulent flames

    E-Print Network [OSTI]

    Raman, Venkat

    number density function. This LES/PDF approach is then used to simulate a turbulent natural gas jet strong correlation between the gas phase composition and soot moments. Ó 2012 The Combustion Institute and the gas-phase composition are often neglected. In this case, the PDF is written as the product of the mar

  8. The interaction of high-speed turbulence with flames: Turbulent flame speed

    SciTech Connect (OSTI)

    Poludnenko, A.Y.; Oran, E.S. [Laboratory for Computational Physics and Fluid Dynamics, Naval Research Laboratory, Washington, DC 20375 (United States)

    2011-02-15

    Direct numerical simulations of the interaction of a premixed flame with driven, subsonic, homogeneous, isotropic, Kolmogorov-type turbulence in an unconfined system are used to study the mechanisms determining the turbulent flame speed, S{sub T}, in the thin reaction zone regime. High intensity turbulence is considered with the r.m.s. velocity 35 times the laminar flame speed, S{sub L}, resulting in the Damkoehler number Da=0.05. The simulations were performed with Athena-RFX, a massively parallel, fully compressible, high-order, dimensionally unsplit, reactive-flow code. A simplified reaction-diffusion model, based on the one-step Arrhenius kinetics, represents a stoichiometric H{sub 2}-air mixture under the assumption of the Lewis number Le=1. Global properties and the internal structure of the flame were analyzed in an earlier paper, which showed that this system represents turbulent combustion in the thin reaction zone regime. This paper demonstrates that: (1) The flame brush has a complex internal structure, in which the isosurfaces of higher fuel mass fractions are folded on progressively smaller scales. (2) Global properties of the turbulent flame are best represented by the structure of the region of peak reaction rate, which defines the flame surface. (3) In the thin reaction zone regime, S{sub T} is predominantly determined by the increase of the flame surface area, A{sub T}, caused by turbulence. (4) The observed increase of S{sub T} relative to S{sub L} exceeds the corresponding increase of A{sub T} relative to the surface area of the planar laminar flame, on average, by {approx}14%, varying from only a few percent to as high as {approx}30%. (5) This exaggerated response is the result of tight flame packing by turbulence, which causes frequent flame collisions and formation of regions of high flame curvature >or similar 1/{delta}{sub L}, or ''cusps,'' where {delta}{sub L} is the thermal width of the laminar flame. (6) The local flame speed in the cusps substantially exceeds its laminar value, which results in a disproportionately large contribution of cusps to S{sub T} compared with the flame surface area in them. (7) A criterion is established for transition to the regime significantly influenced by cusp formation. In particular, at Karlovitz numbers Ka >or similar 20, flame collisions provide an important mechanism controlling S{sub T}, in addition to the increase of A{sub T} by large-scale motions and the potential enhancement of diffusive transport by small-scale turbulence. (author)

  9. Combustion powered linear actuator

    DOE Patents [OSTI]

    Fischer, Gary J. (Albuquerque, NM)

    2007-09-04

    The present invention provides robotic vehicles having wheeled and hopping mobilities that are capable of traversing (e.g. by hopping over) obstacles that are large in size relative to the robot and, are capable of operation in unpredictable terrain over long range. The present invention further provides combustion powered linear actuators, which can include latching mechanisms to facilitate pressurized fueling of the actuators, as can be used to provide wheeled vehicles with a hopping mobility.

  10. The Diesel Combustion Collaboratory: Combustion Researchers Collaborating over the Internet

    SciTech Connect (OSTI)

    C. M. Pancerella; L. A. Rahn; C. Yang

    2000-02-01

    The Diesel Combustion Collaborator (DCC) is a pilot project to develop and deploy collaborative technologies to combustion researchers distributed throughout the DOE national laboratories, academia, and industry. The result is a problem-solving environment for combustion research. Researchers collaborate over the Internet using DCC tools, which include: a distributed execution management system for running combustion models on widely distributed computers, including supercomputers; web-accessible data archiving capabilities for sharing graphical experimental or modeling data; electronic notebooks and shared workspaces for facilitating collaboration; visualization of combustion data; and video-conferencing and data-conferencing among researchers at remote sites. Security is a key aspect of the collaborative tools. In many cases, the authors have integrated these tools to allow data, including large combustion data sets, to flow seamlessly, for example, from modeling tools to data archives. In this paper the authors describe the work of a larger collaborative effort to design, implement and deploy the DCC.

  11. Internal combustion engine using premixed combustion of stratified charges

    DOE Patents [OSTI]

    Marriott, Craig D. (Rochester Hills, MI); Reitz, Rolf D. (Madison, WI

    2003-12-30

    During a combustion cycle, a first stoichiometrically lean fuel charge is injected well prior to top dead center, preferably during the intake stroke. This first fuel charge is substantially mixed with the combustion chamber air during subsequent motion of the piston towards top dead center. A subsequent fuel charge is then injected prior to top dead center to create a stratified, locally richer mixture (but still leaner than stoichiometric) within the combustion chamber. The locally rich region within the combustion chamber has sufficient fuel density to autoignite, and its self-ignition serves to activate ignition for the lean mixture existing within the remainder of the combustion chamber. Because the mixture within the combustion chamber is overall premixed and relatively lean, NO.sub.x and soot production are significantly diminished.

  12. Pressure-gain combustion

    SciTech Connect (OSTI)

    Richards, G.A.; Yip, J.; Gemmen, R.S.; Janus, M.C.; Norton, T. [USDOE Morgantown Energy Technology Center, WV (United States); Rogers, W.A. [EG and G Washington Analytical Services Center, Inc., Morgantown, WV (United States)

    1993-11-01

    Pulse combustion has been proposed for gas turbine applications in many early articles and more recently has been demonstrated to produce so-called ``pressure-gain`` in a small gas turbine. The basic concept is that the oscillatory combustion occurs as a constant-volume process, producing a gain in the stagnation pressure of air flowing through the combustor, rather than the pressure loss associated with conventional, steady combustion. If properly utilized, this pressure-gain could enhance simple-cycle gas turbine efficiency several percent, depending on the operating conditions. In addition, pulse combustors have demonstrated relatively low NO{sub x} pollutant levels in some applications. The combined potential for higher cycle efficiency and lower pollutant levels is the basis for the present investigation. Tests in progress at the Morgantown Energy Technology Center (METC) have considered a baseline pulse combustor configuration that has shown good oscillating performance, low NO{sub x} emissions, but disappointing results in terms of pressure-gain. However, a combination of numeric simulations and test data suggest that pressure-gain can be produced by a select combination of operating conditions and combustor geometry, but is especially sensitive to the combustor inlet geometry. Tests in progress will evaluate the effect of inlet geometry and operating pressure on both pollutant emissions and pressure-gain.

  13. Combustion air preheating

    SciTech Connect (OSTI)

    Wells, T.A.; Petterson, W.C.

    1986-10-14

    This patent describes a process for steam cracking hydrocarbons to cracked gases in a tubular furnace heated by burning a mixture of fuel and combustion air and subsequently quenching the cracked gases. Waste heat is recovered in the form of high pressure steam and the combustion air is preheated prior to introduction into the furnace. The improvement described here comprises: (a) superheating the high pressure steam and expanding at least a portion of the superheated high pressure steam through a first turbine to produce shaft work and superheated medium pressure steam at a temperature between 260/sup 0/ and 465/sup 0/ C.; (b) expanding at least a portion of the superheated medium pressure steam through a second turbine to produce shaft work and low pressure steam at a temperature between 120/sup 0/ and 325/sup 0/ C.; and (c) preheating the combustion air by indirect heat exchange with at least a portion of the superheated medium pressure stream and at least a portion of the low pressure steam.

  14. Observations of Edge Turbulence

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

    Edge Turbulence near the X-point of Alcator C-Mod APS-2007 (1) J.L. Terry, S.J. Zweben*, B. LaBombard, I. Cziegler, O. Grulke + , D.P. Stotler* MIT - Plasma Science and Fusion...

  15. Drying and burning wood waste using pulse combustion

    SciTech Connect (OSTI)

    Buckkowski, A.G.; Eng, P.; Kitchen, J.A. [Novadyne Ltd., Ontario (Canada)

    1995-11-01

    Development of an industrial dryer using pulse combustion as a heating source for drying wood waste has continued. Pulse combustion offers the advantage of high heat transfer, efficient combustion, low NOx emissions and a source of kinetic energy for providing a motive force for a drying system. In our experiments, the drying system consists of a pulse combustor and a vertical drying column. The wood waste is injected into the exhaust gases from the combustor where the turbulence created by the pulsations enhance the drying process by reducing the boundary layer thicknesses. The material is further dried in the vertical drying column, then separated from the conveying airstream using a cyclone. The paper discusses two aspects of the drying system. Firstly, the performance of the drying tests are reviewed. Tests with the 1,000,000 BTU/hr test rig have shown that a gas-fired pulse combustion dryer can dry materials such as sawdust and pulverized hog fuel from a moisture content of 50% down to a 30% in a single pass, or further with multiple passes, without scorching or burning. Preliminary figures show that the operating costs of the dryer are reduced due to the kinetic energy created by the pulse combustor which offsets the use of electricity. Secondly, it has been shown that a pulse combustor can be fired with wood waste and thereby providing the potential to displace natural gas or propane as a fuel. The development of the wood burning combustor is reviewed.

  16. Advanced Combustion Technology to Enable High Efficiency Clean...

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

    Technology to Enable High Efficiency Clean Combustion Advanced Combustion Technology to Enable High Efficiency Clean Combustion Summary of advanced combustion research at Cummins...

  17. US DRIVE Advanced Combustion and Emission Control Technical Team...

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

    Combustion, (2) Dilute Gasoline combustion, and (3) Clean Diesel Combustion. acecroadmapjune2013.pdf More Documents & Publications Overview of the Advanced Combustion Engine...

  18. Fuel Effects on Mixing-Controlled Combustion Strategies for High...

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

    Mixing-Controlled Combustion Strategies for High-Efficiency Clean-Combustion Engines Fuel Effects on Mixing-Controlled Combustion Strategies for High-Efficiency Clean-Combustion...

  19. Low Temperature Combustion Demonstrator for High Efficiency Clean...

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

    Demonstrator for High Efficiency Clean Combustion Low Temperature Combustion Demonstrator for High Efficiency Clean Combustion Applied low temperature combustion to the Navistar...

  20. Low-Temperature Combustion Demonstrator for High-Efficiency Clean...

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

    Low-Temperature Combustion Demonstrator for High-Efficiency Clean Combustion Low-Temperature Combustion Demonstrator for High-Efficiency Clean Combustion 2010 DOE Vehicle...

  1. Low Temperature Combustion Demonstrator for High Efficiency Clean...

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

    Low Temperature Combustion Demonstrator for High Efficiency Clean Combustion Low Temperature Combustion Demonstrator for High Efficiency Clean Combustion 2009 DOE Hydrogen Program...

  2. Internal combustion engine with rotary combustion chamber

    SciTech Connect (OSTI)

    Hansen, C.N.; Cross, P.C.

    1986-09-23

    This patent describes an internal combustion engine comprising: a block having at least one cylindrical wall surrounding a piston chamber, piston means located in the piston chamber means operable to reciprocate the piston means in the chamber, head means mounted on the block covering the chamber. The head means has an air and fuel intake passage, and exhaust gas passage, a rotary valve assembly operatively associated with the head means for controlling the flow of air and fuel into the rotary valve assembly and piston chamber and the flow of exhaust gas from rotary valve assembly and the piston chamber. The means has a housing with a bore open to the piston chamber accommodating the rotary valve assembly, the valve assembly comprising a cylindrical sleeve located in the bore, the sleeve having an inner surface, an ignition hole, and intake and exhaust ports aligned with the intake passage and exhaust gas passage, spark generating means mounted on the housing operable to generate a spark. The rotatable valving means is located within the sleeve for controlling the flow of air and fuel into the rotary valve assembly and piston chamber and the flow of exhaust gases out of the rotary valve assembly and piston chamber.

  3. Vehiculos de combustible flexible: brindando opciones en combustible...

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

    actualizada para convertidores de combustible alternativo de la EPA en su sitio web, www.epa.govotaq certdearmfrcisd0602.pdf. El E85 afecta el desempeo del...

  4. Advanced Combustion Technology to Enable High Efficiency Clean Combustion

    Broader source: Energy.gov [DOE]

    Summary of advanced combustion research at Cummins to explore strategies for fuel economy improvements (PCCI and HECC) and redced engine-out NOx emissions.

  5. Vehicle Technologies Office: Advanced Combustion Strategies

    Broader source: Energy.gov [DOE]

    The Vehicle Technologies Office (VTO) funds research focused on developing a greater understanding of engine combustion and how emissions form within engine cylinders. This work includes research on low temperature combustion, dilute (lean-burn) gasoline combustion, and clean diesel combustion, all of which can substantially contribute to increasing efficiency and lowering emissions in internal combustion engines.

  6. Tire gassification and combustion system

    SciTech Connect (OSTI)

    Nance, D.; Towne, G.A.

    1992-04-07

    This patent describes a system for disposing of a material such as vehicle tires and similar substantially organic matter and generating useful heat therefrom. It comprises gasification means for holding an amount of the material to be disposed while the material is allowed to partially combust and for containing combustible gas produced thereby, the gasification means comprising a substantially air tight gasification chamber having at least one access way for inserting the material therein; inlet means for receiving a controlled amount of oxygen containing gas into the gasification means, the inlet means comprising a tuyere disposed in the air tight gasification chamber and a blower connected to the tuyere; removal means for removing the combustible gas from the gasification means, the removal means comprising a gas outlet located above the tuyere in the gasification chamber such that substantially amounts of the combustible gases produced by the partially combusted material exits through the gas outlet; primary combustion means for receiving and mixing the combustible gas removed from the gasification means with an oxygen containing gas and burning the combustible gas; and means for directing the combustion products to a heat utilizing device.

  7. ALS Evidence Confirms Combustion Theory

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

    ALS Evidence Confirms Combustion Theory Print Researchers recently uncovered the first step in the process that transforms gas-phase molecules into solid particles like soot and...

  8. An Embedded Boundary Method for the Modeling of Unsteady Combustion in an Industrial GasFired Furnace \\Lambda

    E-Print Network [OSTI]

    Bell, John B.

    the simulation of an experimental natural gas­fired furnace are shown. 1 Introduction The ability to model the simulation of an experimental natural gas­fired furnace are shown. \\Lambda This work was performed under a a two­step scheme for natural gas combustion [30] coupled with a simplified turbulent kinetics model [6

  9. Power-law wrinkling turbulence-flame interaction model for astrophysical flames

    SciTech Connect (OSTI)

    Jackson, Aaron P.; Townsley, Dean M.; Calder, Alan C.

    2014-04-01

    We extend a model for turbulence-flame interactions (TFI) to consider astrophysical flames with a particular focus on combustion in Type Ia supernovae. The inertial range of the turbulent cascade is nearly always under-resolved in simulations of astrophysical flows, requiring the use of a model in order to quantify the effects of subgrid-scale wrinkling of the flame surface. We provide implementation details to extend a well-tested TFI model to low-Prandtl number flames for use in the compressible hydrodynamics code FLASH. A local, instantaneous measure of the turbulent velocity is calibrated for FLASH and verification tests are performed. Particular care is taken to consider the relation between the subgrid rms turbulent velocity and the turbulent flame speed, especially for high-intensity turbulence where the turbulent flame speed is not expected to scale with the turbulent velocity. Finally, we explore the impact of different TFI models in full-star, three-dimensional simulations of Type Ia supernovae.

  10. Strained flamelets for turbulent premixed flames II: Laboratory flame results

    SciTech Connect (OSTI)

    Kolla, H.; Swaminathan, N. [Department of Engineering, Cambridge University, Cambridge CB2 1PZ (United Kingdom)

    2010-07-15

    The predictive ability of strained flamelets model for turbulent premixed flames is assessed using Reynolds Averaged Navier Stokes (RANS) calculations of laboratory flames covering a wide range of conditions. Reactant-to-product (RtP) opposed flow laminar flames parametrised using the scalar dissipation rate of reaction progress variable are used as strained flamelets. Two turbulent flames: a rod stabilised V-flame studied by Robin et al. [Combust. Flame 153 (2008) 288-315] and a set of pilot stabilised Bunsen flames studied by Chen et al. [Combust. Flame 107 (1996) 223-244] are calculated using a single set of model parameters. The V-flame corresponds to the corrugated flamelets regime. The strained flamelet model and an unstrained flamelet model yield similar predictions which are in good agreement with experimental measurements for this flame. On the other hand, for the Bunsen flames which are in the thin reaction zones regime, the unstrained flamelet model predicts a smaller flame brush compared to experiment. The predictions of the strained flamelets model allowing for fluid-dynamics stretch induced attenuation of the chemical reaction are in good agreement with the experimental data. This model predictions of major and minor species are also in good agreement with experimental data. The results demonstrate that the strained flamelets model using the scalar dissipation rate can be used across the combustion regimes. (author)

  11. Combustion Byproducts Recycling Consortium

    SciTech Connect (OSTI)

    Ziemkiewicz, Paul; Vandivort, Tamara; Pflughoeft-Hassett, Debra; Chugh, Y Paul; Hower, James

    2008-08-31

    Each year, over 100 million tons of solid byproducts are produced by coal-burning electric utilities in the United States. Annual production of flue gas desulfurization (FGD) byproducts continues to increase as the result of more stringent sulfur emission restrictions. In addition, stricter limits on NOx emissions mandated by the 1990 Clean Air Act have resulted in utility burner/boiler modifications that frequently yield higher carbon concentrations in fly ash, which restricts the use of the ash as a cement replacement. Controlling ammonia in ash is also of concern. If newer, “clean coal” combustion and gasification technologies are adopted, their byproducts may also present a management challenge. The objective of the Combustion Byproducts Recycling Consortium (CBRC) is to develop and demonstrate technologies to address issues related to the recycling of byproducts associated with coal combustion processes. A goal of CBRC is that these technologies, by the year 2010, will lead to an overall ash utilization rate from the current 34% to 50% by such measures as increasing the current rate of FGD byproduct use and increasing in the number of uses considered “allowable” under state regulations. Another issue of interest to the CBRC would be to examine the environmental impact of both byproduct utilization and disposal. No byproduct utilization technology is likely to be adopted by industry unless it is more cost-effective than landfilling. Therefore, it is extremely important that the utility industry provide guidance to the R&D program. Government agencies and privatesector organizations that may be able to utilize these materials in the conduct of their missions should also provide input. The CBRC will serve as an effective vehicle for acquiring and maintaining guidance from these diverse organizations so that the proper balance in the R&D program is achieved.

  12. Experimental study of turbulent flame kernel propagation

    SciTech Connect (OSTI)

    Mansour, Mohy [National Institute of Laser Enhanced Sciences, Cairo University, Giza (Egypt); Peters, Norbert; Schrader, Lars-Uve [Institute of Combustion Technology, Aachen (Germany)

    2008-07-15

    Flame kernels in spark ignited combustion systems dominate the flame propagation and combustion stability and performance. They are likely controlled by the spark energy, flow field and mixing field. The aim of the present work is to experimentally investigate the structure and propagation of the flame kernel in turbulent premixed methane flow using advanced laser-based techniques. The spark is generated using pulsed Nd:YAG laser with 20 mJ pulse energy in order to avoid the effect of the electrodes on the flame kernel structure and the variation of spark energy from shot-to-shot. Four flames have been investigated at equivalence ratios, {phi}{sub j}, of 0.8 and 1.0 and jet velocities, U{sub j}, of 6 and 12 m/s. A combined two-dimensional Rayleigh and LIPF-OH technique has been applied. The flame kernel structure has been collected at several time intervals from the laser ignition between 10 {mu}s and 2 ms. The data show that the flame kernel structure starts with spherical shape and changes gradually to peanut-like, then to mushroom-like and finally disturbed by the turbulence. The mushroom-like structure lasts longer in the stoichiometric and slower jet velocity. The growth rate of the average flame kernel radius is divided into two linear relations; the first one during the first 100 {mu}s is almost three times faster than that at the later stage between 100 and 2000 {mu}s. The flame propagation is slightly faster in leaner flames. The trends of the flame propagation, flame radius, flame cross-sectional area and mean flame temperature are related to the jet velocity and equivalence ratio. The relations obtained in the present work allow the prediction of any of these parameters at different conditions. (author)

  13. Sandia Energy - Engine Combustion

    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 of NaturalDukeWakefieldSulfateSciTechtail.Theory ofDid youOxygen GenerationTechnologiesEnergy ConversionEngine Combustion Home

  14. Sandia Energy - Combustion Kinetics

    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 RoomPreservation of Fe(II) byMultidayAlumniProjects Caterpillar, SandiaCombustion Kinetics Home

  15. Sandia Energy - Spray Combustion

    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 RoomPreservation of Fe(II)GeothermalFuel Magnetization and Laser(TSPEARSolarSpray Combustion Home

  16. Sandia Energy - Spray Combustion

    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 RoomPreservation of Fe(II)GeothermalFuel Magnetization and Laser(TSPEARSolarSpray Combustion

  17. Combustion Catalysts in Industry- An Update 

    E-Print Network [OSTI]

    Merrell, G. A.; Knight, R. S.

    1985-01-01

    combustibles in the refuse and help a plant attain emissions compliance requirements that are not always achieved with pollution-control equipment. Combustion catalysts promote the combustion process by lowering the ignition temperature of the fuel, allowing...

  18. Path planning during combustion mode switch

    DOE Patents [OSTI]

    Jiang, Li; Ravi, Nikhil

    2015-12-29

    Systems and methods are provided for transitioning between a first combustion mode and a second combustion mode in an internal combustion engine. A current operating point of the engine is identified and a target operating point for the internal combustion engine in the second combustion mode is also determined. A predefined optimized transition operating point is selected from memory. While operating in the first combustion mode, one or more engine actuator settings are adjusted to cause the operating point of the internal combustion engine to approach the selected optimized transition operating point. When the engine is operating at the selected optimized transition operating point, the combustion mode is switched from the first combustion mode to the second combustion mode. While operating in the second combustion mode, one or more engine actuator settings are adjusted to cause the operating point of the internal combustion to approach the target operating point.

  19. COMBUSTION-GENERATED INDOOR AIR POLLUTION

    E-Print Network [OSTI]

    Hollowell, C.D.

    2010-01-01

    x A Emission Characteristics in Two Stage Combustion. PaperInternational) on Combustion, Tokyo (August, 1974). Chang,fll , J I ___F J "J LBL-S9lS COMBUSTION-GENERATED INDOOR AIR

  20. COMBUSTION-GENERATED INDOOR AIR POLLUTION

    E-Print Network [OSTI]

    Hollowell, C.D.

    2010-01-01

    of indoor combustion-generated air pollution in residen-LBL-S9lS COMBUSTION-GENERATED INDOOR AIR POLLUTION Dr. C. D.L,BL-5918 COMBUSTION-GENERATED INDOOR AIR POLLUTION C. D.

  1. Multidimensional turbulence spectra -identifying properties of turbulent structures

    E-Print Network [OSTI]

    Kevlahan, Nicholas

    Sweden 2 Department of Mathematics and Statistics, McMaster University, Hamilton L8S 4K1, Canada * E turbulent structures are presented. Results from analysis of the turbulent kinetic energy in turbulent energy associated with a coherent vortex defined using different vortex identification methods

  2. Quantum ghost imaging through turbulence

    E-Print Network [OSTI]

    Dixon, P. Ben

    We investigate the effect of turbulence on quantum ghost imaging. We use entangled photons and demonstrate that for a specific experimental configuration the effect of turbulence can be greatly diminished. By decoupling ...

  3. Rotary reciprical combustion engines

    SciTech Connect (OSTI)

    Blount, D.H.

    1992-10-20

    This patent describes a rotary-reciprocal combustion engine having a cycle which includes the four strokes of intake, compression, expansion and exhaustion, the engine. It comprises: a housing formed with a peripheral wall with side walls, a rotor in the housing, the inner surface of the peripheral inner wall being cylindrical; a shaft; mounted in the center of the housing, passing through the rotor's hub and extending through the side walls of the housing, the hub having means to allow the rotor to reciprocate on the shaft while the shaft is rotating with the rotor; a reciprocal and rotary guide having means to guide the rotary and reciprocal motions of the rotor while keeping the rotor's piston in continuous sealing contact with the cylinder chamber walls and varying the volume of the cylinder chambers enabling a compression of a gaseous mixture to take place after aspirating a gaseous mixture; an ignition system having means for igniting compressed gaseous mixture and expansion of the cylinder chambers due to pressure of the combustion products.

  4. Utilization ROLE OF COAL COMBUSTION

    E-Print Network [OSTI]

    Wisconsin-Milwaukee, University of

    , materials left after combustion of coal in conventional and/ or advanced clean-coal technology combustors and advanced clean-coal technology combustors. This paper describes various coal combustion products produced (FGD) products from pulverized coal and advanced clean-coal technology combustors. Over 70% of the CCPs

  5. Spark ignition of lifted turbulent jet flames

    SciTech Connect (OSTI)

    Ahmed, S.F.; Mastorakos, E. [Hopkinson Laboratory, Department of Engineering, University of Cambridge, Cambridge CB2 1PZ (United Kingdom)

    2006-07-15

    This paper presents experiments on ignition and subsequent edge flame propagation in turbulent nonpremixed methane jets in air. The spark position, energy, duration, electrode diameter and gap, and the jet velocity and air premixing of the fuel stream are examined to study their effects on the ignition probability defined as successful flame establishment. The flame is visualized by a high-speed camera and planar laser-induced fluorescence of OH. It was found that after an initially spherical shape, the flame took a cylindrical shape with a propagating edge upstream. The probability of successful ignition increases with high spark energy, thin electrode diameter and wide gap, but decreases with increasing dilution of the jet with air. The flame kernel growth rate is high when the ignition probability is high for all parameters, except for jet velocity. Increasing the jet velocity decreases the ignition probability at all locations. The average flame position as a function of time from the spark was measured and the data were used to estimate a net propagation speed, which then resulted in an estimate of the average edge flame speed relative to the incoming flow. This was about 3 to 6 laminar burning velocities of a stoichiometric mixture. The measurements can assist theoretical models for the probability of ignition of nonpremixed flames and for edge flame propagation in turbulent inhomogeneous mixtures, both of which determine the success of ignition in practical combustion systems. (author)

  6. Integrated Nozzle Flow, Spray, Combustion, & Emission Modeling...

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

    Nozzle Flow, Spray, Combustion, & Emission Modeling using KH-ACT Primary Breakup Model & Detailed Chemistry Integrated Nozzle Flow, Spray, Combustion, & Emission Modeling using...

  7. Sandia Energy - Particle Ignition and Char Combustion

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

    of CO2 and H2O (from flue gas recirculation) create very different physical and chemical properties of the combustion medium, influencing coal ignition and combustion rates....

  8. Optimizing Low Temperature Diesel Combustion | Department of...

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

    Optimizing Low Temperature Diesel Combustion Optimizing Low Temperature Diesel Combustion Presentation from the U.S. DOE Office of Vehicle Technologies "Mega" Merit Review 2008 on...

  9. Hydrogen engine and combustion control process

    DOE Patents [OSTI]

    Swain, Michael R. (Coral Gables, FL); Swain, Matthew N. (Miami, FL)

    1997-01-01

    Hydrogen engine with controlled combustion comprises suction means connected to the crankcase reducing or precluding flow of lubricating oil or associated gases into the combustion chamber.

  10. Thermodynamic Advantages of Low Temperature Combustion Engines...

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

    Advantages of Low Temperature Combustion Engines Including the Use of Low Heat Rejection Concepts Thermodynamic Advantages of Low Temperature Combustion Engines Including the Use...

  11. Combustion Model for Engine Concept Development | Department...

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

    Model for Engine Concept Development Combustion Model for Engine Concept Development Presentation shows how 1-cylinder testing, 3D combustion CFD and 1D gas exchange with an...

  12. Particle Sensor for Diesel Combustion Monitoring | Department...

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

    Sensor for Diesel Combustion Monitoring Particle Sensor for Diesel Combustion Monitoring 2004 Diesel Engine Emissions Reduction (DEER) Conference Presentation: University of...

  13. Improved Solvers for Advanced Engine Combustion Simulation

    Broader source: Energy.gov [DOE]

    Document:  ace076_mcnenly_2013_o.pdfTechnology Area: Advanced Combustion; Combustion and Emissions ControlPresenter: Matthew McNenlyPresenting Organization: Lawrence Livermore National Laboratory ...

  14. Large eddy simulation of unsteady lean stratified premixed combustion

    SciTech Connect (OSTI)

    Duwig, C.; Fureby, C.

    2007-10-15

    Premixed turbulent flame-based technologies are rapidly growing in importance, with applications to modern clean combustion devices for both power generation and aeropropulsion. However, the gain in decreasing harmful emissions might be canceled by rising combustion instabilities. Unwanted unsteady flame phenomena that might even destroy the whole device have been widely reported and are subject to intensive studies. In the present paper, we use unsteady numerical tools for simulating an unsteady and well-documented flame. Computations were performed for nonreacting, perfectly premixed and stratified premixed cases using two different numerical codes and different large-eddy-simulation-based flamelet models. Nonreacting simulations are shown to agree well with experimental data, with the LES results capturing the mean features (symmetry breaking) as well as the fluctuation level of the turbulent flow. For reacting cases, the uncertainty induced by the time-averaging technique limited the comparisons. Given an estimate of the uncertainty, the numerical results were found to reproduce well the experimental data in terms both of mean flow field and of fluctuation levels. In addition, it was found that despite relying on different assumptions/simplifications, both numerical tools lead to similar predictions, giving confidence in the results. Moreover, we studied the flame dynamics and particularly the response to a periodic pulsation. We found that above a certain excitation level, the flame dynamic changes and becomes rather insensitive to the excitation/instability amplitude. Conclusions regarding the self-growth of thermoacoustic waves were drawn. (author)

  15. Theoretical studies on hydrogen ignition and droplet combustion

    E-Print Network [OSTI]

    Del Álamo, Gonzalo

    2006-01-01

    the combustion of hydrogen and carbon monoxide. Combustionfor carbon-monoxide hydrogen oxygen kinetics. Combustion

  16. Wave turbulent statistics in non-weak wave turbulence

    E-Print Network [OSTI]

    Naoto Yokoyama

    2011-05-08

    In wave turbulence, it has been believed that statistical properties are well described by the weak turbulence theory, in which nonlinear interactions among wavenumbers are assumed to be small. In the weak turbulence theory, separation of linear and nonlinear time scales derived from the weak nonlinearity is also assumed. However, the separation of the time scales is often violated even in weak turbulent systems where the nonlinear interactions are actually weak. To get rid of this inconsistency, closed equations are derived without assuming the separation of the time scales in accordance with Direct-Interaction Approximation (DIA), which has been successfully applied to Navier--Stokes turbulence. The kinetic equation of the weak turbulence theory is recovered from the DIA equations if the weak nonlinearity is assumed as an additional assumption. It suggests that the DIA equations is a natural extension of the conventional kinetic equation to not-necessarily-weak wave turbulence.

  17. Rotary internal combustion engine

    SciTech Connect (OSTI)

    Murray, J.L.; Mosca, J.O.

    1992-02-25

    This patent describes a rotary internal combustion engine. It includes a housing; a cam track internally disposed within the housing and adapted to receive a cam follower; an engine block disposed within the housing, the engine block being relatively rotatable within the housing about a central axis; means connectable to an external drive member for translating the relative rotation of the engine block with respect to the housing into useful work; at least one radially arranged cylinder assembly on the block, each cylinder assembly including a cylinder having a longitudinal axis extending generally radially outwardly from the rotational axis of the block, the cylinder including means defining an end wall, a piston member disposed within the cylinder and adapted to reciprocate within the cylinder; the piston, cylinder and cylinder end wall together.

  18. Characterization of Relativistic MHD Turbulence

    E-Print Network [OSTI]

    Garrison, David

    2015-01-01

    The objective of this work is to understand if and how the characteristics of relativistic MHD turbulence may differ from those of nonrelativistic MHD turbulence. We accomplish this by studying the invariants in the relativistic case and comparing them to what we know of nonrelativistic turbulence. Although much work has been done to understand the dynamics of nonrelativistic systems (mostly for ideal incompressible fluids), there is minimal literature explicitly describing the dynamics of relativistic MHD turbulence. Many authors simply assume that relativistic turbulence has the same invariants and obeys the same inverse energy cascade as non-relativistic systems.

  19. Response of flame thickness and propagation speed under intense turbulence in spatially developing lean premixed methane–air jet flames

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

    Sankaran, Ramanan; Hawkes, Evatt R.; Yoo, Chun Sang; Chen, Jacqueline H.

    2015-06-22

    Direct numerical simulations of three-dimensional spatially-developing turbulent Bunsen flames were performed at three different turbulence intensities. We performed these simulations using a reduced methane–air chemical mechanism which was specifically tailored for the lean premixed conditions simulated here. A planar-jet turbulent Bunsen flame configuration was used in which turbulent preheated methane–air mixture at 0.7 equivalence ratio issued through a central jet and was surrounded by a hot laminar coflow of burned products. The turbulence characteristics at the jet inflow were selected such that combustion occured in the thin reaction zones (TRZ) regime. At the lowest turbulence intensity, the conditions fall onmore »the boundary between the TRZ regime and the corrugated flamelet regime, and progressively moved further into the TRZ regime by increasing the turbulent intensity. The data from the three simulations was analyzed to understand the effect of turbulent stirring on the flame structure and thickness. Furthermore, statistical analysis of the data showed that the thermal preheat layer of the flame was thickened due to the action of turbulence, but the reaction zone was not significantly affected. A global and local analysis of the burning velocity of the flame was performed to compare the different flames. Detailed statistical averages of the flame speed were also obtained to study the spatial dependence of displacement speed and its correlation to strain rate and curvature.« less

  20. Response of flame thickness and propagation speed under intense turbulence in spatially developing lean premixed methane air jet flames

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

    Sankaran, Ramanan; Hawkes, Evatt R.; Yoo, Chun Sang; Chen, Jacqueline H.

    2015-06-22

    Direct numerical simulations of three-dimensional spatially-developing turbulent Bunsen flames were performed at three different turbulence intensities. We performed these simulations using a reduced methane–air chemical mechanism which was specifically tailored for the lean premixed conditions simulated here. A planar-jet turbulent Bunsen flame configuration was used in which turbulent preheated methane–air mixture at 0.7 equivalence ratio issued through a central jet and was surrounded by a hot laminar coflow of burned products. The turbulence characteristics at the jet inflow were selected such that combustion occured in the thin reaction zones (TRZ) regime. At the lowest turbulence intensity, the conditions fall onmore »the boundary between the TRZ regime and the corrugated flamelet regime, and progressively moved further into the TRZ regime by increasing the turbulent intensity. The data from the three simulations was analyzed to understand the effect of turbulent stirring on the flame structure and thickness. Furthermore, statistical analysis of the data showed that the thermal preheat layer of the flame was thickened due to the action of turbulence, but the reaction zone was not significantly affected. A global and local analysis of the burning velocity of the flame was performed to compare the different flames. Detailed statistical averages of the flame speed were also obtained to study the spatial dependence of displacement speed and its correlation to strain rate and curvature.« less

  1. Twenty-Seventh Symposium (International) on Combustion/The Combustion Institute, 1998/pp. 28152820 FINGERING INSTABILITY IN SOLID FUEL COMBUSTION

    E-Print Network [OSTI]

    Moses, Elisha

    2815 Twenty-Seventh Symposium (International) on Combustion/The Combustion Institute, 1998/pp. 2815­2820 FINGERING INSTABILITY IN SOLID FUEL COMBUSTION: THE CHARACTERISTIC SCALES OF THE DEVELOPED STATE ORY ZIK, Israel We present new results on the fingering instability in solid fuel combustion. The instability

  2. Lawrence Berkeley National Laboratory report LBNL-54198 Numerical Simulation of a Laboratory-Scale Turbulent V-flame

    E-Print Network [OSTI]

    detailed chemical kinetics and a mixture model for differential species diffusion. Methane chemistry are performed us- ing an adaptive time-dependent low Mach number combustion algorithm based on a second of realistic chemical kinetics in a turbulent flow field, and the present limitations in experimental

  3. Feature-Based Statistical Analysis of Combustion Simulation Data

    SciTech Connect (OSTI)

    Bennett, J; Krishnamoorthy, V; Liu, S; Grout, R; Hawkes, E; Chen, J; Pascucci, V; Bremer, P T

    2011-11-18

    We present a new framework for feature-based statistical analysis of large-scale scientific data and demonstrate its effectiveness by analyzing features from Direct Numerical Simulations (DNS) of turbulent combustion. Turbulent flows are ubiquitous and account for transport and mixing processes in combustion, astrophysics, fusion, and climate modeling among other disciplines. They are also characterized by coherent structure or organized motion, i.e. nonlocal entities whose geometrical features can directly impact molecular mixing and reactive processes. While traditional multi-point statistics provide correlative information, they lack nonlocal structural information, and hence, fail to provide mechanistic causality information between organized fluid motion and mixing and reactive processes. Hence, it is of great interest to capture and track flow features and their statistics together with their correlation with relevant scalar quantities, e.g. temperature or species concentrations. In our approach we encode the set of all possible flow features by pre-computing merge trees augmented with attributes, such as statistical moments of various scalar fields, e.g. temperature, as well as length-scales computed via spectral analysis. The computation is performed in an efficient streaming manner in a pre-processing step and results in a collection of meta-data that is orders of magnitude smaller than the original simulation data. This meta-data is sufficient to support a fully flexible and interactive analysis of the features, allowing for arbitrary thresholds, providing per-feature statistics, and creating various global diagnostics such as Cumulative Density Functions (CDFs), histograms, or time-series. We combine the analysis with a rendering of the features in a linked-view browser that enables scientists to interactively explore, visualize, and analyze the equivalent of one terabyte of simulation data. We highlight the utility of this new framework for combustion science; however, it is applicable to many other science domains.

  4. Droplet Combustion and Non-Reactive Shear-Coaxial Jets with Transverse Acoustic Excitation

    E-Print Network [OSTI]

    Teshome, Sophonias

    2012-01-01

    Related Works in Droplet Combustion . . . . . . . .of Acoustics on Droplet Combustion . . . . . . . . . . . .Fuel Droplet Combustion . . . . . . . . . . . . . . .

  5. Static magnetic fields enhance turbulence

    E-Print Network [OSTI]

    Pothérat, Alban

    2015-01-01

    More often than not, turbulence occurs under the influence of external fields, mostly rotation and magnetic fields generated either by planets, stellar objects or by an industrial environment. Their effect on the anisotropy and the dissipative behaviour of turbulence is recognised but complex, and it is still difficult to even tell whether they enhance or dampen turbulence. For example, externally imposed magnetic fields suppress free turbulence in electrically conducting fluids (Moffatt 1967), and make it two-dimensional (2D) (Sommeria & Moreau 1982); but their effect on the intensity of forced turbulence, as in pipes, convective flows or otherwise, is not clear. We shall prove that since two-dimensionalisation preferentially affects larger scales, these undergo much less dissipation and sustain intense turbulent fluctuations. When higher magnetic fields are imposed, quasi-2D structures retain more kinetic energy, so that rather than suppressing forced turbulence, external magnetic fields indirectly enha...

  6. Low Temperature Combustion Demonstrator for High Efficiency Clean Combustion

    Broader source: Energy.gov [DOE]

    Applied low temperature combustion to the Navistar 6.4L V8 engine with 0.2g NOx/bhp-hr operation attained at the rated 16.5 BMEP

  7. International combustion engines; Applied thermosciences

    SciTech Connect (OSTI)

    Ferguson, C.R.

    1985-01-01

    Focusing on thermodynamic analysis - from the requisite first law to more sophisticated applications - and engine design, this book is an introduction to internal combustion engines and their mechanics. It covers the many types of internal combustion engines, including spark ignition, compression ignition, and stratified charge engines, and examines processes, keeping equations of state simple by assuming constant specific heats. Equations are limited to heat engines and later applied to combustion engines. Topics include realistic equations of state, stroichiometry, predictions of chemical equilibrium, engine performance criteria, and friction, which is discussed in terms of the hydrodynamic theory of lubrication and experimental methods such as dimensional analysis.

  8. The Combustion Institute 5001 Baum Boulevard

    E-Print Network [OSTI]

    Tennessee, University of

    The Combustion Institute 5001 Baum Boulevard Pittsburgh, Pennsylvania, USA 15213-1851 CENTRAL STATES SECTION OF THE COMBUSTION INSTITUTE CALL FOR PAPERS TECHNICAL MEETING - SPRING 2002 COMBUSTION 7-9, 2002 #12;CENTRAL STATES SECTION OF THE COMBUSTION INSTITUTE www.cssci.org CALL FOR PAPERS

  9. COMBUSTION SYNTHESIS OF ADVANCED MATERIALS: PRINCIPLESAND APPLICATIONS

    E-Print Network [OSTI]

    Mukasyan, Alexander

    COMBUSTION SYNTHESIS OF ADVANCED MATERIALS: PRINCIPLESAND APPLICATIONS Arvind Varma, Alexander S. Gasless Combustion SynthesisFrom Elements B. Combustion Synthesis in Gas-Solid Systems C. Products of Thermite-vpe SHS D. Commercial Aspects IV. Theoretical Considerations A. Combustion Wave Propagation Theory

  10. Combustion characteristics of indolene-methanol blends in a CFR spark ignition engine

    SciTech Connect (OSTI)

    Patel, K.S.

    1984-01-01

    A study of the combustion characteristics of indolene, methanol and indolene-methanol blends has been completed. The investigation included theoretical and experimental parts. In the theoretical part, turbulent burning velocity, laminar burning velocity, and mass burning velocity are computed. The experimental part was completed on a CFR spark ignition engine using indolene, methanol, and indolene-methanol blends. Methanol concentration was varied from 0 to 100 vol.%. For each blend, compression ratio was varied from 5.0 to KLCR (Knock Limited Compression Ratio). The results of theoretical analysis showed that the laminar burning velocity increased as the vol.% of methanol increased. The experimental results indicated that adding methanol to indolene, MBT (Minimum advanced for Best Torque) spark advance, volumetric efficiency, brake mean effective pressure are decreased while break specific fuel consumption, brake thermal efficiency an KLCR are increased. The theoretical and experimental results showed that adding methanol to indolene, apparent flame speed, turbulent burning velocity and the ratio of turbulent to laminar burning velocity increased. Pure methanol produced the highest turbulent burning velocity. It is concluded that methanol has considerable effect on the combustion characteristics of spark ignition engine.

  11. High Efficiency, Clean Combustion

    SciTech Connect (OSTI)

    Donald Stanton

    2010-03-31

    Energy use in trucks has been increasing at a faster rate than that of automobiles within the U.S. transportation sector. According to the Energy Information Administration (EIA) Annual Energy Outlook (AEO), a 23% increase in fuel consumption for the U.S. heavy duty truck segment is expected between 2009 to 2020. The heavy duty vehicle oil consumption is projected to grow between 2009 and 2050 while light duty vehicle (LDV) fuel consumption will eventually experience a decrease. By 2050, the oil consumption rate by LDVs is anticipated to decrease below 2009 levels due to CAFE standards and biofuel use. In contrast, the heavy duty oil consumption rate is anticipated to double. The increasing trend in oil consumption for heavy trucks is linked to the vitality, security, and growth of the U.S. economy. An essential part of a stable and vibrant U.S. economy is a productive U.S. trucking industry. Studies have shown that the U.S. gross domestic product (GDP) is strongly correlated to freight transport. Over 90% of all U.S. freight tonnage is transported by diesel power and over 75% is transported by trucks. Given the vital role that the trucking industry plays in the economy, improving the efficiency of the transportation of goods was a central focus of the Cummins High Efficient Clean Combustion (HECC) program. In a commercial vehicle, the diesel engine remains the largest source of fuel efficiency loss, but remains the greatest opportunity for fuel efficiency improvements. In addition to reducing oil consumption and the dependency on foreign oil, this project will mitigate the impact on the environment by meeting US EPA 2010 emissions regulations. Innovation is a key element in sustaining a U.S. trucking industry that is competitive in global markets. Unlike passenger vehicles, the trucking industry cannot simply downsize the vehicle and still transport the freight with improved efficiency. The truck manufacturing and supporting industries are faced with numerous challenges to reduce oil consumption and greenhouse gases, meet stringent emissions regulations, provide customer value, and improve safety. The HECC program successfully reduced engine fuel consumption and greenhouse gases while providing greater customer valve. The US EPA 2010 emissions standard poses a significant challenge for developing clean diesel powertrains that meet the DoE Vehicle Technologies Multi-Year Program Plan (MYPP) for fuel efficiency improvement while remaining affordable. Along with exhaust emissions, an emphasis on heavy duty vehicle fuel efficiency is being driven by increased energy costs as well as the potential regulation of greenhouse gases. An important element of the success of meeting emissions while significantly improving efficiency is leveraging Cummins component technologies such as fuel injection equipment, aftertreatment, turbomahcinery, electronic controls, and combustion systems. Innovation in component technology coupled with system integration is enabling Cummins to move forward with the development of high efficiency clean diesel products with a long term goal of reaching a 55% peak brake thermal efficiency for the engine plus aftertreatment system. The first step in developing high efficiency clean products has been supported by the DoE co-sponsored HECC program. The objectives of the HECC program are: (1) To design and develop advanced diesel engine architectures capable of achieving US EPA 2010 emission regulations while improving the brake thermal efficiency by 10% compared to the baseline (a state of the art 2007 production diesel engine). (2) To design and develop components and subsystems (fuel systems, air handling, controls, etc) to enable construction and development of multi-cylinder engines. (3) To perform an assessment of the commercial viability of the newly developed engine technology. (4) To specify fuel properties conducive to improvements in emissions, reliability, and fuel efficiency for engines using high-efficiency clean combustion (HECC) technologies. To demonstrate the technology is compatible with B2

  12. Dilute Oxygen Combustion Phase I Final Report

    SciTech Connect (OSTI)

    Ryan, H.M.; Riley, M.F.; Kobayashi, H.

    1997-10-31

    A novel burner, in which fuel (natural gas) and oxidant (oxygen or air) are separately injected into a furnace, shows promise for achieving very low nitrogen oxide(s) (NOx) emissions for commercial furnace applications. The dilute oxygen combustion (DOC) burner achieves very low NOx through in-furnace dilution of the oxidant stream prior to combustion, resulting in low flame temperatures, thus inhibiting thermal NOx production. The results of a fundamental and applied research effort on the development of the DOC burner are presented. In addition, the results of a market survey detailing the potential commercial impact of the DOC system are disclosed. The fundamental aspects of the burner development project involved examining the flame characteristics of a natural gas turbulent jet in a high-temperature (~1366 K) oxidant (7-27% O2 vol. wet). Specifically, the mass entrainment rate, the flame lift-off height, the velocity field and major species field of the jet were evaluated as a function of surrounding-gas temperature and composition. The measured entrainment rate of the fuel jet decreased with increasing oxygen content in the surrounding high-temperature oxidant, and was well represented by the d+ scaling correlation found in the literature. The measured flame lift-off height decreased with increasing oxygen content and increasing temperature of the surrounding gas. An increase in surrounding-gas oxygen content and/or temperature inhibited the velocity decay within the jet periphery as a function of axial distance as compared to isothermal turbulent jets. However, the velocity measurements were only broadly represented by the d+ scaling correlation. Several DOC burner configurations were tested in a laboratory-scale furnace at a nominal firing rate of 185 kW (~0.63 MMBtu/h). The flue gas composition was recorded as a function of furnace nitrogen content, furnace temperature, burner geometric arrangement, firing rate, and fuel injection velocity. NOx emissions increased with increasing furnace nitrogen content and furnace temperature, but remained relatively insensitive to variations in fuel injection velocity and firing rate. NOx emissions below 5-10-3 g/MJ (10 ppm-air equivalent at 3% O2 dry) were obtained for furnace temperatures below 1533 K (2300°F) and furnace nitrogen levels between 1 and 40%. CO emissions were typically low (<35 ppm). Detailed in-furnace species measurements revealed the importance of the interior furnace circulation patterns, as influenced by fuel and oxidant injection schemes, on pollutant emissions. The combustion stability traits of several DOC burner arrangements were ascertained through furnace pressure measurements, wit6h increased stability occurring as furnace temperature increased and as the separation distance between fuel and oxidant inputs decreased. Based on current market conditions, oxy-fuel conversion of batch steel reheat furnaces with a DOC burner is justified on the basis of lower utility costs alone. However, conversion of continuous steel reheat furnaces, which are responsible for most steel production, required additional economic incentives, such as further fuel savings, increased furnace productivity, or emission credits.

  13. Dilute oxygen combustion. Phase I report

    SciTech Connect (OSTI)

    NONE

    1997-10-01

    A novel burner, in which fuel (natural gas) and oxidant (oxygen or air) are separately injected into a furnace, shows promise for achieving very low nitrogen oxide(s) (NO{sub x}) emissions for commercial furnace applications. The dilute oxygen combustion (DOC) burner achieves very low NO{sub x} through in-furnace dilution of the oxidant stream prior to combustion, resulting in low flame temperatures, thus inhibiting thermal NO{sub x} production. The results of a fundamental and applied research effort on the development of the DOC burner are presented. In addition, the results of a market survey detailing the potential commercial impact of the DOC system are disclosed. The fundamental aspects of the burner development project involved examining the flame characteristics of a natural gas turbulent jet in a high-temperature ({approximately}1366 K) oxidant (7-27% O{sub 2} vol. wet). Specifically, the mass entrainment rate, the flame lift-off height, the velocity field and major species field of the jet were evaluated as a function of surrounding-gas temperature and composition. The measured entrainment rate of the fuel jet decreased with increasing oxygen content in the surrounding high-temperature oxidant, and was well represented by the d{sup +} scaling correlation found in the literature. The measured flame lift-off height decreased with increasing oxygen content and increasing temperature of the surrounding gas. An increase in surrounding-gas oxygen content and/or temperature inhibited the velocity decay within the jet periphery as a function of axial distance as compared to isothermal turbulent jets. However, the velocity measurements were only broadly represented by the d{sup +} scaling correlation. Several DOC burner configurations were tested in a laboratory-scale furnace at a nominal firing rate of 185 kW ({approximately}0.63 MMBtu/h). The flue gas composition was recorded as a function of furnace nitrogen content, furnace temperature, burner geometric arrangement, firing rate, and fuel injection velocity. NO{sub x} emissions increased with increasing furnace nitrogen content and furnace temperature, but remained relatively insensitive to variations in fuel injection velocity and firing rate. NO{sub x} emissions below 5{times}10{sup -3} g/MJ (10 ppm-air equivalent at 3% O{sub 2} dry) were obtained for furnace temperatures below 1533 K (2300{degree}F) and furnace nitrogen levels between 1 and 40%. CO emissions were typically low (<35 ppm). Detailed in- furnace species measurements revealed the importance of the interior furnace circulation patterns, as influenced by fuel and oxidant injection schemes, on pollutant emissions. The combustion stability traits of several DOC burner arrangements were ascertained through furnace pressure measurements, with increased stability occurring as furnace temperature increased and as the separation distance between fuel and oxidant inputs decreased. Based on current market conditions, oxy-fuel conversion of batch steel reheat furnaces with a DOC burner is justified on the basis of utility costs alone. However, conversion of continuous steel reheat furnaces, which are responsible for most steel production, requires additional economic incentives, such as further fuel savings, increased furnace productivity, or emission credits.

  14. Combustion Science for Cleaner Fuels

    SciTech Connect (OSTI)

    Ahmed, Musahid

    2014-10-17

    Musahid Ahmed discusses how he and his team use the Advanced Light Source (ALS) to study combustion chemistry at our '8 Big Ideas' Science at the Theater event on October 8th, 2014, in Oakland, California.

  15. Loop-bed combustion apparatus

    DOE Patents [OSTI]

    Shang, Jer-Yu (Fairfax, VA); Mei, Joseph S. (Morgantown, WV); Slagle, Frank D. (Kingwood, WV); Notestein, John E. (Morgantown, WV)

    1984-01-01

    The present invention is directed to a combustion apparatus in the configuration of a oblong annulus defining a closed loop. Particulate coal together with a sulfur sorbent such as sulfur or dolomite is introduced into the closed loop, ignited, and propelled at a high rate of speed around the loop. Flue gas is withdrawn from a location in the closed loop in close proximity to an area in the loop where centrifugal force imposed upon the larger particulate material maintains these particulates at a location spaced from the flue gas outlet. Only flue gas and smaller particulates resulting from the combustion and innerparticle grinding are discharged from the combustor. This structural arrangement provides increased combustion efficiency due to the essentially complete combustion of the coal particulates as well as increased sulfur absorption due to the innerparticle grinding of the sorbent which provides greater particle surface area.

  16. ALS Evidence Confirms Combustion Theory

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

    in incomplete combustion of organic matter (e.g., in engines and incinerators, when biomass burns in forest fires). PAHs may also be abundant in the universe, and are...

  17. Predictive modeling of combustion processes

    E-Print Network [OSTI]

    Sharma, Sandeep, Ph. D. Massachusetts Institute of Technology

    2009-01-01

    Recently, there has been an increasing interest in improving the efficiency and lowering the emissions from operating combustors, e.g. internal combustion (IC) engines and gas turbines. Different fuels, additives etc. are ...

  18. Combustion modeling in waste tanks

    SciTech Connect (OSTI)

    Mueller, C.; Unal, C.; Travis, J.R. |

    1997-08-01

    This paper has two objectives. The first one is to repeat previous simulations of release and combustion of flammable gases in tank SY-101 at the Hanford reservation with the recently developed code GASFLOW-II. The GASFLOW-II results are compared with the results obtained with the HMS/TRAC code and show good agreement, especially for non-combustion cases. For combustion GASFLOW-II predicts a steeper pressure rise than HMS/TRAC. The second objective is to describe a so-called induction parameter model which was developed and implemented into GASFLOW-II and reassess previous calculations of Bureau of Mines experiments for hydrogen-air combustion. The pressure time history improves compared with the one-step model, and the time rate of pressure change is much closer to the experimental data.

  19. Engine combustion and flow diagnostics

    SciTech Connect (OSTI)

    1995-12-31

    This informative publication discusses the application of diagnostic techniques to internal combustion engines. The papers included fall into three broad categories: flow diagnostics, combustion diagnostics, and fuel spray diagnostics. Contents include: controlling combustion in a spark ignition engine by quantitative fuel distribution; a model for converting SI engine flame arrival signals into flame contours; in-cylinder diesel flame imaging compared with numerical computations; ignition and early soot formation in a DI diesel engine using multiple 2-D imaging diagnostics; investigation of diesel sprays using diffraction-based droplet sizing; fuel distribution effects on the combustion of a direct-injection stratified-charge engine; and 2-D measurements of the liquid phase temperature in fuel sprays.

  20. Rotary-reciprocal combustion engines

    SciTech Connect (OSTI)

    Blount, D.H.

    1992-10-06

    This patent describes an internal combustion engine of the rotary-reciprocal type. It comprises a housing formed with a peripheral wall; a rotor; and a shaft for the rotor.

  1. Reducing mode circulating fluid bed combustion

    DOE Patents [OSTI]

    Lin, Yung-Yi (Katy, TX); Sadhukhan, Pasupati (Katy, TX); Fraley, Lowell D. (Sugarland, TX); Hsiao, Keh-Hsien (Houston, TX)

    1986-01-01

    A method for combustion of sulfur-containing fuel in a circulating fluid bed combustion system wherein the fuel is burned in a primary combustion zone under reducing conditions and sulfur captured as alkaline sulfide. The reducing gas formed is oxidized to combustion gas which is then separated from solids containing alkaline sulfide. The separated solids are then oxidized and recycled to the primary combustion zone.

  2. Combustion of hydrogen:air mixtures in the VGES cylindrical tank. [PWR; BWR

    SciTech Connect (OSTI)

    Benedick, W.B.; Cummings, J.C.; Prassinos, P.G.

    1984-05-01

    Sandia National Laboratories is currently involved in a number of experimental projects to provide data that will help quantify the threat of hydrogen combustion during nuclear plant accidents. Several experimental facilities are part of the Variable Geometry Experimental System (VGES). The purpose of this report is to document the experimental results from the first round of combustion tests performed at one of these facilities: a 5-m/sup 3/ cylindrical tank. The data provided by tests at this facility can be used to guide further testing and for the development and assessment of analytical models to predict hydrogen combustion behavior.

  3. Pulse enhanced fluidized bed combustion

    SciTech Connect (OSTI)

    Mueller, B.; Golan, L. [South Carolina Energy Research and Development Center, Clemson, SC (United States); Toma, M.; Mansour, M. [Manufacturing and Technology Conversion International, Inc., Columbia, MD (United States)

    1996-12-31

    Various technologies are available for the combustion of high-sulfur, high-ash fuels, particularly coal. From performance, economic and environmental standpoints, fluidized bed combustion (FBC) is the leading candidate for utilization of high sulfur coals. ThermoChem, Inc., and the South Carolina Energy Research and Development Center (SCERDC) are installing a hybrid fluidized bed combustion system at Clemson University. This hybrid system, known as the Pulsed Atmospheric Fluidized Bed Combustor (PAFBC), will augment the University`s steam system by providing 50--60,000 lbs/hr of saturated process steam. The PAFBC, developed by Manufacturing and Technology Conversion International, Inc., (MTCI), integrates a pulse combustor with a bubbling-bed-type atmospheric fluidized bed coal combustor. The pulse combustion system imparts an acoustic effect that enhances combustion efficiency, SO{sub 2} capture, low NO{sub x} emissions, and heat transfer efficiency in the fluidized bed. These benefits of pulse combustion result in modestly sized PAFBC units with high throughput rates and lower costs when compared to conventional fluidized bed units.

  4. Aerovalve pulse combustion: Technical note

    SciTech Connect (OSTI)

    Richards, G.A.; Gemmen, R.S.; Narayanaswami, L.

    1994-07-01

    The authors present a mathematical model and an experimental investigation of aerodynamically valved pulse combustion. The model uses a control-volume approach to solve conservation laws in several regions of a pulse combustor. Mixing between the fresh charge and combustion products is modeled as a two-step process, with the mixing occurring slowly for a specified eddy time during each cycle, and then changing to a higher rate. Results of model simulations demonstrate that eddy time plays a significant role in determining the frequency and amplitude of combustion oscillation. The authors show that short eddy times produce steady, rather than pulsating, combustion. And they show that changes to the mixing process alter the temperature-species history of combustion gases in a manner that could prevent or promote the formation of nitrogen oxides, depending on specific mixing rates. The relatively simple control-volume approach used in this model allows rapid investigation of a wide range of geometric and operating parameters, and also defines characteristic length and time scales relevant to aerovalve pulse combustion. Experimental measurements compare favorably to model predictions. The authors place particular emphasis on time-averaged pressure differences through the combustor, which act as an indicator of pressure gain performance. They investigate both operating conditions and combustor geometry, and they show that a complex interaction between the inlet and exit flows of a combustor makes it difficult to produce general correlations among the various parameters. They use a scaling rule to produce a combustor geometry capable of producing pressure gain.

  5. Polymer Stretching by Turbulence

    SciTech Connect (OSTI)

    Chertkov, Michael

    2000-05-15

    The stretching of a polymer chain by a large-scale chaotic flow is considered. The steady state which emerges as a balance of the turbulent stretching and anharmonic resistance of the chain is quantitatively described, i.e., the dependency on the flow parameters (Lyapunov exponent statistics) and the chain characteristics (the number of beads and the interbead elastic potential) is made explicit. (c) 2000 The American Physical Society.

  6. Few-Freedom Turbulence

    E-Print Network [OSTI]

    B. V. Chirikov; V. G. Davidovsky

    2000-06-15

    The results of numerical experiments on the structure of chaotic attractors in the Khalatnikov - Kroyter model of two freedoms are presented. This model was developed for a qualitative description of the wave turbulence of the second sound in helium. The attractor dimension, size, and the maximal Lyapunov exponent in dependence on the single dimensionless parameter $F$ of the model are found and discussed. The principal parameter $F$ is similar to the Reynolds number in hydrodynamic turbulence. We were able to discern four different attractors characterized by a specific critical value of the parameter ($F=F_{cr}$), such that the attractor exists for $F>F_{cr}$ only. A simple empirical relation for this dependence on the argument ($F-F_{cr}$) is presented which turns out to be universal for different attractors with respect to the dimension and dimensionless Lyapunov exponents. Yet, it differs as to the size of attractor. In the main region of our studies the dependence of all dimensionless characteristics of the chaotic attractor on parameter $F$ is very slow (logarithmic) which is qualitatively different as compared to that of a multi-freedom attractor, e.g., in hydrodynamic turbulence (a power law). However, at very large $F\\sim 10^7$ the transition to a power-law dependence has been finally found, similar to the multi-freedom attractor. Some unsolved problems and open questions are also discussed.

  7. COMBUSTION OF COAL IN AN OPPOSED FLOW DIFFUSION BURNER

    E-Print Network [OSTI]

    Chin, W.K.

    2010-01-01

    J.M. , liThe F1uidised Combustion of Coal," Sixteenth Sm osium {International} on Combustion, August 1976 (to beof Various Polymers Under Combustion Conditions," Fourteenth

  8. Multicylinder Diesel Engine for Low Temperature Combustion Operation...

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

    for Low Temperature Combustion Operation Multicylinder Diesel Engine for Low Temperature Combustion Operation Fuel injection strategies to extend low temperature combustion...

  9. Using Biofuel Tracers to Study Alternative Combustion Regimes

    E-Print Network [OSTI]

    Mack, John Hunter; Flowers, Daniel L.; Buchholz, Bruce A.; Dibble, Robert W.

    2006-01-01

    1979. J.B. Heywood, Internal Combustion Engine Fundamentals.Ignition Engine with Optimal Combustion Control. ” US PatentIntroduction to Internal Combustion Engines (3rd Edition).

  10. COMBUSTION SOURCES OF UNREGULATED GAS PHASE NITROGENEOUS SPECIES

    E-Print Network [OSTI]

    Matthews, Ronald D.

    2013-01-01

    SAE Paper 750173, 1975. L. , Fifteenth Symposium Combustion,The Combustion Institute, International Pittsburgh, on 64.chemistry of products of combustion: nitrogenous The

  11. Advanced High Efficiency Clean Diesel Combustion with Low Cost...

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

    Efficiency Clean Diesel Combustion with Low Cost for Hybrid Engines Advanced High Efficiency Clean Diesel Combustion with Low Cost for Hybrid Engines Clean, in-cylinder combustion...

  12. COMBUSTION RESEARCH PROGRAM. CHAPTER FROM ENERGY & ENVIRONMENT ANNUAL REPORT 1977

    E-Print Network [OSTI]

    Authors, Various

    2011-01-01

    of combustion systems while minimizing the pollutionthe combustion process to reduce the associa- ted pollution.combustion problems. Several are directly related to pollution

  13. Eddy fluxes in baroclinic turbulence

    E-Print Network [OSTI]

    Thompson, Andrew F.

    2006-01-01

    cant dissipation of tidal energy in the deep ocean inferred2006: An estimate of tidal energy lost to turbulence at the

  14. Combustion Byproducts Recycling Consortium

    SciTech Connect (OSTI)

    Paul Ziemkiewicz; Tamara Vandivort; Debra Pflughoeft-Hassett; Y. Paul Chugh; James Hower

    2008-08-31

    The Combustion Byproducts Recycling Consortium (CBRC) program was developed as a focused program to remove and/or minimize the barriers for effective management of over 123 million tons of coal combustion byproducts (CCBs) annually generated in the USA. At the time of launching the CBRC in 1998, about 25% of CCBs were beneficially utilized while the remaining was disposed in on-site or off-site landfills. During the ten (10) year tenure of CBRC (1998-2008), after a critical review, 52 projects were funded nationwide. By region, the East, Midwest, and West had 21, 18, and 13 projects funded, respectively. Almost all projects were cooperative projects involving industry, government, and academia. The CBRC projects, to a large extent, successfully addressed the problems of large-scale utilization of CCBs. A few projects, such as the two Eastern Region projects that addressed the use of fly ash in foundry applications, might be thought of as a somewhat smaller application in comparison to construction and agricultural uses, but as a novel niche use, they set the stage to draw interest that fly ash substitution for Portland cement might not attract. With consideration of the large increase in flue gas desulfurization (FGD) gypsum in response to EPA regulations, agricultural uses of FGD gypsum hold promise for large-scale uses of a product currently directed to the (currently stagnant) home construction market. Outstanding achievements of the program are: (1) The CBRC successfully enhanced professional expertise in the area of CCBs throughout the nation. The enhanced capacity continues to provide technology and information transfer expertise to industry and regulatory agencies. (2) Several technologies were developed that can be used immediately. These include: (a) Use of CCBs for road base and sub-base applications; (b) full-depth, in situ stabilization of gravel roads or highway/pavement construction recycled materials; and (c) fired bricks containing up to 30%-40% F-fly ash. Some developed technologies have similar potential in the longer term. (3) Laboratory studies have been completed that indicate that much higher amounts of fly ash could be added in cement-concrete applications under some circumstances. This could significantly increase use of fly ash in cement-concrete applications. (4) A study of the long-term environmental effects of structural fills in a surface mine in Indiana was completed. This study has provided much sought after data for permitting large-volume management options in both beneficial as well as non-beneficial use settings. (5) The impact of CBRC on CCBs utilization trends is difficult to quantify. However it is fair to say that the CBRC program had a significant positive impact on increased utilization of CCBs in every region of the USA. Today, the overall utilization of CCBs is over 43%. (6) CBRC-developed knowledge base led to a large number of other projects completed with support from other sources of funding. (7) CBRC research has also had a large impact on CCBs management across the globe. Information transfer activities and visitors from leading coal producing countries such as South Africa, Australia, England, India, China, Poland, Czech Republic and Japan are truly noteworthy. (8) Overall, the CBRC has been a truly successful, cooperative research program. It has brought together researchers, industry, government, and regulators to deal with a major problem facing the USA and other coal producing countries in the world.

  15. Internal combustion engine

    SciTech Connect (OSTI)

    Evans, H.G.; Speer, S.

    1991-12-31

    This patent describes improvement in a 2-cycle, diesel cycle internal combustion engine comprising a single in-line engine block, internal wall surfaces defining at least one cylinder within the engine block, the central longitudinal axis of each cylinder being within a common plane extending longitudinally of the engine block, the axially extending internal wall surface of each cylinder being closed at one end and having at least one air intake port therethrough, a piston axially and reciprocally movable within each cylinder over a permitted stroke distance, so as to alternately cover and expose each air intake port for a finite time period; an exhaust port at the closed end of the cylinder above the piston, and a mechanically operated valve for opening and closing such exhaust port located immediately adjacent such port, a substantially rigid connecting rod pivotably connected at one end of each piston, and a crankshaft, rotatably connected to the second end of each connecting rod, such that the crankshaft is caused to rotate connecting means between the piston and the connecting rod. The improvement comprises the diameter of the cylinder is greater than the permitted stroke distance of the piston within the cylinder, and the axis of the crankshaft is parallel to and laterally offset from the common plane by a distance sufficient to form an angle alpha between the connecting rod and the axis of the cylinder, when the piston is at top-dead center, of at least about 12 degrees, such that the time during which each air intake port is exposed is increased when the direction of crankshaft rotation is opposite to the direction of the crankshaft offset from the common plane.

  16. Evidence for internal structures of spiral turbulence

    E-Print Network [OSTI]

    2009-12-21

    Dec 22, 2009 ... ary laminar-turbulent pattern in plane Couette flow. ... flow internal to the turbulent and laminar spirals, and unique ... 2 ( is the fluid density).

  17. Supercomputers Capture Turbulence in the Solar Wind

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

    Capture Turbulence in the Solar Wind Supercomputers Capture Turbulence in the Solar Wind Berkeley Lab visualizations could help scientists forecast destructive space weather...

  18. Method and apparatus for detecting combustion instability in continuous combustion systems

    DOE Patents [OSTI]

    Benson, Kelly J.; Thornton, Jimmy D.; Richards, George A.; Straub, Douglas L.

    2006-08-29

    An apparatus and method to sense the onset of combustion stability is presented. An electrode is positioned in a turbine combustion chamber such that the electrode is exposed to gases in the combustion chamber. A control module applies a voltage potential to the electrode and detects a combustion ionization signal and determines if there is an oscillation in the combustion ionization signal indicative of the occurrence of combustion stability or the onset of combustion instability. A second electrode held in a coplanar but spaced apart manner by an insulating member from the electrode provides a combustion ionization signal to the control module when the first electrode fails. The control module broadcasts a notice if the parameters indicate the combustion process is at the onset of combustion instability or broadcasts an alarm signal if the parameters indicate the combustion process is unstable.

  19. Combustion | Argonne National Laboratory

    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 OutreachProductswsicloudwsiclouddenDVA N C E D BGene NetworkNuclearDNP Post-Doctoral Position in DirectEFRC

  20. Stratified charge internal combustion engine

    SciTech Connect (OSTI)

    Skopil, A.O.

    1991-01-01

    This patent describes an internal combustion engine. It comprises: a main cylinder, a main piston within the main cylinder, and means for delivering a combustible charge into the main cylinder; a smaller idle cylinder, and idle piston within the idle cylinder, and means for delivering a combustible charge into the idle cylinder; an ignition passageway leading from the idle cylinder to the main cylinder; and an ignition device within the ignition passageway operable to ignite a compressed charge discharged by the idle cylinder into the ignition passageway. The passageway being positioned to discharge the ignited compressed charge from the idle cylinder into the main cylinder to ignite the compressed charge within the main cylinder.

  1. Steam boosted internal combustion engine

    SciTech Connect (OSTI)

    Green, M.A.

    1987-01-20

    A device is described to supplement the power produced by burning fuel in an internal combustion engine with steam, the device comprising: a means for producing a constant flow of water past a boiler means; a means for allowing the water to flow in the direction of the boiler; a boiler means external to the internal combustion engine to convert the water into superheated steam; a means for controlling the pressure of the water such that the water pressure is greater than the pressure of the steam produced by the boiler; and a means for injection of the superheated steam directly into a cylinder of the internal combustion engine, a means for producing a constant flow of water at a pressure greater than the pressure of the superheated steam, wherein the constant flow means at greater pressure comprises a chamber with a gaseous component, with the gaseous component being of constant volume and exerting constant pressure upon water within the chamber.

  2. Advances in compressible turbulent mixing

    SciTech Connect (OSTI)

    Dannevik, W.P.; Buckingham, A.C.; Leith, C.E.

    1992-01-01

    This volume includes some recent additions to original material prepared for the Princeton International Workshop on the Physics of Compressible Turbulent Mixing, held in 1988. Workshop participants were asked to emphasize the physics of the compressible mixing process rather than measurement techniques or computational methods. Actual experimental results and their meaning were given precedence over discussions of new diagnostic developments. Theoretical interpretations and understanding were stressed rather than the exposition of new analytical model developments or advances in numerical procedures. By design, compressibility influences on turbulent mixing were discussed--almost exclusively--from the perspective of supersonic flow field studies. The papers are arranged in three topical categories: Foundations, Vortical Domination, and Strongly Coupled Compressibility. The Foundations category is a collection of seminal studies that connect current study in compressible turbulent mixing with compressible, high-speed turbulent flow research that almost vanished about two decades ago. A number of contributions are included on flow instability initiation, evolution, and transition between the states of unstable flow onset through those descriptive of fully developed turbulence. The Vortical Domination category includes theoretical and experimental studies of coherent structures, vortex pairing, vortex-dynamics-influenced pressure focusing. In the Strongly Coupled Compressibility category the organizers included the high-speed turbulent flow investigations in which the interaction of shock waves could be considered an important source for production of new turbulence or for the enhancement of pre-existing turbulence. Individual papers are processed separately.

  3. Energy spectra in bubbly turbulence

    E-Print Network [OSTI]

    Prakash, Vivek N; Ramos, Fabio Ernesto Mancilla; Tagawa, Yoshiyuki; Lohse, Detlef; Sun, Chao

    2013-01-01

    We conduct experiments in a turbulent bubbly flow to study the unknown nature of the transition between the classical -5/3 energy spectrum scaling for a single-phase turbulent flow and the -3 scaling for a swarm of bubbles rising in a quiescent liquid and of bubble-dominated turbulence. The bubblance parameter, b, which measures the ratio of the bubble-induced kinetic energy to the kinetic energy induced by the turbulent liquid fluctuations before bubble injection, is used to characterise the bubbly flow. We vary b from $b = \\infty$ (pseudo-turbulence) to b = 0 (single-phase flow) over 2-3 orders of magnitude: ~O(0.01, 0.1, 5) to study its effect on the turbulent energy spectrum and liquid velocity fluctuations. The experiments are conducted in a multi-phase turbulent water tunnel with air bubbles of diameters 2-4 mm and 3-5 mm. An active-grid is used to generate nearly homogeneous and isotropic turbulence in the liquid flow. The liquid speeds and gas void fractions are varied to achieve the above mentioned b...

  4. Combustion instability modeling and analysis

    SciTech Connect (OSTI)

    Santoro, R.J.; Yang, V.; Santavicca, D.A.; Sheppard, E.J.

    1995-12-31

    It is well known that the two key elements for achieving low emissions and high performance in a gas turbine combustor are to simultaneously establish (1) a lean combustion zone for maintaining low NO{sub x} emissions and (2) rapid mixing for good ignition and flame stability. However, these requirements, when coupled with the short combustor lengths used to limit the residence time for NO formation typical of advanced gas turbine combustors, can lead to problems regarding unburned hydrocarbons (UHC) and carbon monoxide (CO) emissions, as well as the occurrence of combustion instabilities. The concurrent development of suitable analytical and numerical models that are validated with experimental studies is important for achieving this objective. A major benefit of the present research will be to provide for the first time an experimentally verified model of emissions and performance of gas turbine combustors. The present study represents a coordinated effort between industry, government and academia to investigate gas turbine combustion dynamics. Specific study areas include development of advanced diagnostics, definition of controlling phenomena, advancement of analytical and numerical modeling capabilities, and assessment of the current status of our ability to apply these tools to practical gas turbine combustors. The present work involves four tasks which address, respectively, (1) the development of a fiber-optic probe for fuel-air ratio measurements, (2) the study of combustion instability using laser-based diagnostics in a high pressure, high temperature flow reactor, (3) the development of analytical and numerical modeling capabilities for describing combustion instability which will be validated against experimental data, and (4) the preparation of a literature survey and establishment of a data base on practical experience with combustion instability.

  5. Vorticity dynamics after the shock–turbulence interaction

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

    Livescu, Daniel; Ryu, Jaiyoung

    2015-07-23

    In this article, the interaction of a shock wave with quasi-vortical isotropic turbulence (IT) represents a basic problem for studying some of the phenomena associated with high speed flows, such as hypersonic flight, supersonic combustion and Inertial Confinement Fusion (ICF). In general, in practical applications, the shock width is much smaller than the turbulence scales and the upstream turbulent Mach number is modest. In this case, recent high resolution shock-resolved Direct Numerical Simulations (DNS) (Ryu and Livescu, J Fluid Mech 756, R1, 2014) show that the interaction can be described by the Linear Interaction Approximation (LIA). Using LIA to alleviatemore »the need to resolve the shock, DNS post-shock data can be generated at much higher Reynolds numbers than previously possible. Here, such results with Taylor Reynolds number approximately 180 are used to investigate the changes in the vortical structure as a function of the shock Mach number, Ms, up to Ms = 10. It is shown that, as Ms increases, the shock interaction induces a tendency towards a local axisymmetric state perpendicular to the shock front, which has a profound influence on the vortex-stretching mechanism and divergence of the Lamb vector and, ultimately, on the flow evolution away from the shock.« less

  6. Chemical kinetics and combustion modeling

    SciTech Connect (OSTI)

    Miller, J.A. [Sandia National Laboratories, Livermore, CA (United States)

    1993-12-01

    The goal of this program is to gain qualitative insight into how pollutants are formed in combustion systems and to develop quantitative mathematical models to predict their formation rates. The approach is an integrated one, combining low-pressure flame experiments, chemical kinetics modeling, theory, and kinetics experiments to gain as clear a picture as possible of the process in question. These efforts are focused on problems involved with the nitrogen chemistry of combustion systems and on the formation of soot and PAH in flames.

  7. Combustion synthesis method and products

    DOE Patents [OSTI]

    Holt, J.B.; Kelly, M.

    1993-03-30

    Disclosed is a method of producing dense refractory products, comprising: (a) obtaining a quantity of exoergic material in powder form capable of sustaining a combustion synthesis reaction; (b) removing absorbed water vapor therefrom; (c) cold-pressing said material into a formed body; (d) plasma spraying said formed body with a molten exoergic material to form a coat thereon; and (e) igniting said exoergic coated formed body under an inert gas atmosphere and pressure to produce self-sustained combustion synthesis. Also disclosed are products produced by the method.

  8. Engine Combustion Network Experimental Data

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

    Maintained by the Engine Combustion Department of Sandia National Laboratories, data currently available on the website includes reacting and non-reacting sprays in a constant-volume chamber at conditions typical of diesel combustion. The data are useful for model development and validation because of the well-defined boundary conditions and the wide range of conditions employed. A search utility displays data based on experimental conditions such as ambient temperature, ambient density, injection pressure, nozzle size, fuel, etc. Experiment-related visualizations are also available. The search utility for experimental data is located at http://public.ca.sandia.gov/ecn/cvdata/frameset.html (Specialized Interface)

  9. Combustion heater for oil shale

    DOE Patents [OSTI]

    Mallon, R.; Walton, O.; Lewis, A.E.; Braun, R.

    1983-09-21

    A combustion heater for oil shale heats particles of spent oil shale containing unburned char by burning the char. A delayed fall is produced by flowing the shale particles down through a stack of downwardly sloped overlapping baffles alternately extending from opposite sides of a vertical column. The delayed fall and flow reversal occurring in passing from each baffle to the next increase the residence time and increase the contact of the oil shale particles with combustion supporting gas flowed across the column to heat the shale to about 650 to 700/sup 0/C for use as a process heat source.

  10. Combustion heater for oil shale

    DOE Patents [OSTI]

    Mallon, Richard G. (Livermore, CA); Walton, Otis R. (Livermore, CA); Lewis, Arthur E. (Los Altos, CA); Braun, Robert L. (Livermore, CA)

    1985-01-01

    A combustion heater for oil shale heats particles of spent oil shale containing unburned char by burning the char. A delayed fall is produced by flowing the shale particles down through a stack of downwardly sloped overlapping baffles alternately extending from opposite sides of a vertical column. The delayed fall and flow reversal occurring in passing from each baffle to the next increase the residence time and increase the contact of the oil shale particles with combustion supporting gas flowed across the column to heat the shale to about 650.degree.-700.degree. C. for use as a process heat source.

  11. Formation mechanisms of combustion chamber deposits

    E-Print Network [OSTI]

    O'Brien, Christopher J. (Christopher John)

    2001-01-01

    Combustion chamber deposits are found in virtually all internal combustion engines after a few hundred hours of operation. Deposits form on cylinder, piston, and head surfaces that are in contact with fuel-air mixture ...

  12. Free Energy and Internal Combustion Engine Cycles

    E-Print Network [OSTI]

    William D. Harris

    2012-01-11

    The performance of one type (Carnot) of Internal Combustion Engine (ICE) cycle is analyzed within the framework of thermodynamic free energies. ICE performance is different from that of an External Combustion Engine (ECE) which is dictated by Carnot's rule.

  13. Free Energy and Internal Combustion Engine Cycles

    E-Print Network [OSTI]

    Harris, William D

    2012-01-01

    The performance of one type (Carnot) of Internal Combustion Engine (ICE) cycle is analyzed within the framework of thermodynamic free energies. ICE performance is different from that of an External Combustion Engine (ECE) which is dictated by Carnot's rule.

  14. Computation of azimuthal combustion instabilities in an helicopter combustion chamber

    E-Print Network [OSTI]

    Nicoud, Franck

    to compute azimuthal combustion instabilities is presented. It requires a thermoacoustic model using a n is investigated. Introduction Thermoacoustic instabilities result from the coupling between unstationary low CPU time cost. A thermoacoustic model is used to solve the wave equation in reactive media

  15. Effects of Advanced Combustion Technologies on Particulate Matter...

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

    Advanced Combustion Technologies on Particulate Matter Emissions Characteristics Effects of Advanced Combustion Technologies on Particulate Matter Emissions Characteristics...

  16. Combustion Synthesis of Silicon Carbide 389 Combustion Synthesis of Silicon Carbide

    E-Print Network [OSTI]

    Mukasyan, Alexander

    Combustion Synthesis of Silicon Carbide 389 X Combustion Synthesis of Silicon Carbide Alexander S. Mukasyan University of Notre Dame USA 1. Introduction Combustion synthesis (CS) is an effective technique by which combustion synthesis can occur: self - propagating high-temperature synthesis (SHS) and volume

  17. Supersonic combustion studies using a multivariate quadrature based method for combustion modeling

    E-Print Network [OSTI]

    Raman, Venkat

    Supersonic combustion studies using a multivariate quadrature based method for combustion modeling function (PDF) of thermochemical variables can be used for accurately computing the combustion source term of predictive models for supersonic combustion is a critical step in design and development of scramjet engines

  18. The turbulent/non-turbulent interface at the outer boundary of a self-similar turbulent jet

    E-Print Network [OSTI]

    Hunt, Julian

    The turbulent/non-turbulent interface at the outer boundary of a self-similar turbulent jet J-similar turbulent jet at Re=2·103 is investigated ex- perimentally by means of combined particle image velo- cimetry (PIV) laser-induced fluorescence (LIF) measurements. The jet fluid contains a fluorescent dye so

  19. Plasmatron Fuel Reformer Development and Internal Combustion...

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

    Vehicle Applications Plasmatron Fuel Reformer Development and Internal Combustion Engine Vehicle Applications 2004 Diesel Engine Emissions Reduction (DEER) Conference...

  20. Zinc Bromide Combustion: Implications for the Consolidated Incinerator Facility

    SciTech Connect (OSTI)

    Oji, L.N.

    1998-12-16

    In the nuclear industry, zinc bromide (ZnBr2) is used for radiation shielding. At Savannah River Site (SRS) zinc bromide solution, in appropriate configurations and housings, was used mainly for shielding in viewing windows in nuclear reactor and separation areas. Waste stream feeds that will be incinerated at the CIF will occasionally include zinc bromide solution/gel matrices.The CIF air pollution systems control uses a water-quench and steam atomizer scrubber that collects salts, ash and trace metals in the liquid phase. Water is re-circulated in the quench unit until a predetermined amount of suspended solids or dissolved salts are present. After reaching the threshold limit, "dirty liquid", also called "blowdown", is pumped to a storage tank in preparation for treatment and disposal. The air pollution control system is coupled to a HEPA pre-filter/filter unit, which removes particulate matter from the flue gas stream (1).The objective of this report is to review existing literature data on the stability of zinc bromide (ZnBr2) at CIF operating temperatures (>870 degrees C (1600 degrees F) and determine what the combustion products are in the presence of excess air. The partitioning of the combustion products among the quencher/scrubber solution, bottom ash and stack will also be evaluated. In this report, side reactions between zinc bromide and its combustion products with fuel oil were not taken into consideration.

  1. Method and device for diagnosing and controlling combustion instabilities in internal combustion engines operating in or transitioning to homogeneous charge combustion ignition mode

    DOE Patents [OSTI]

    Wagner, Robert M [Knoxville, TN; Daw, Charles S [Knoxville, TN; Green, Johney B [Knoxville, TN; Edwards, Kevin D [Knoxville, TN

    2008-10-07

    This invention is a method of achieving stable, optimal mixtures of HCCI and SI in practical gasoline internal combustion engines comprising the steps of: characterizing the combustion process based on combustion process measurements, determining the ratio of conventional and HCCI combustion, determining the trajectory (sequence) of states for consecutive combustion processes, and determining subsequent combustion process modifications using said information to steer the engine combustion toward desired behavior.

  2. Combustor nozzle for a fuel-flexible combustion system

    DOE Patents [OSTI]

    Haynes, Joel Meier (Niskayuna, NY); Mosbacher, David Matthew (Cohoes, NY); Janssen, Jonathan Sebastian (Troy, NY); Iyer, Venkatraman Ananthakrishnan (Mason, OH)

    2011-03-22

    A combustor nozzle is provided. The combustor nozzle includes a first fuel system configured to introduce a syngas fuel into a combustion chamber to enable lean premixed combustion within the combustion chamber and a second fuel system configured to introduce the syngas fuel, or a hydrocarbon fuel, or diluents, or combinations thereof into the combustion chamber to enable diffusion combustion within the combustion chamber.

  3. Reduced No.sub.x combustion method

    DOE Patents [OSTI]

    Delano, Mark A. (Briarcliff Manor, NY)

    1991-01-01

    A combustion method enabling reduced NO.sub.x formation wherein fuel and oxidant are separately injected into a combustion zone in a defined velocity relation, combustion gases are aspirated into the oxidant stream prior to intermixture with the fuel, and the fuel is maintained free from contact with oxygen until the intermixture.

  4. Pressure Gain Combustion Rotating Detonation Engines (RDE)

    E-Print Network [OSTI]

    Pressure Gain Combustion Rotating Detonation Engines (RDE) Dr. Chris Brophy, David Dausen, Lee Van Houtte Students LT Culwell, ENS Khol, Robert Wright, Andrew Chaves Rocket Propulsion & Combustion Lab-based combustion to extract increase thermodynamic cycle efficiency for work/thrust apps. · Higher Enthalpy

  5. BEP Proposal: Towards Cleaner Industrial Combustion -

    E-Print Network [OSTI]

    Vuik, Kees

    BEP Proposal: Towards Cleaner Industrial Combustion - How to Reduce the Formation of Pollutants furnace fired by the combustion of natural gas. The chemical reaction of the gas and oxygen mixture releases heat and side products such as water and carbon monoxide. The combustion also produces undesired

  6. Combustion joining of refractory materials: Carboncarbon composites

    E-Print Network [OSTI]

    Mukasyan, Alexander

    Combustion joining of refractory materials: Carbon­carbon composites Jeremiah D.E. White Department­carbon composite is achieved by employing self-sustained, oxygen-free, high-temperature combustion reactions to a used "core" to produce a brake that meets the performance specifications. The combustion-joining (CJ

  7. Three-dimensional hydrodynamic simulations of the combustion of a neutron star into a quark star

    E-Print Network [OSTI]

    Matthias Herzog; Friedrich K. Roepke

    2011-09-02

    We present three-dimensional numerical simulations of turbulent combustion converting a neutron star into a quark star. Hadronic matter, described by a micro-physical finite-temperature equation of state, is converted into strange quark matter. We assume this phase, represented by a bag-model equation of state, to be absolutely stable. Following the example of thermonuclear burning in white dwarfs leading to Type Ia supernovae, we treat the conversion process as a potentially turbulent deflagration. Solving the non-relativistic Euler equations using established numerical methods we conduct large eddy simulations including an elaborate subgrid scale model, while the propagation of the conversion front is modeled with a level-set method. Our results show that for large parts of the parameter space the conversion becomes turbulent and therefore significantly faster than in the laminar case. Despite assuming absolutely stable strange quark matter, in our hydrodynamic approximation an outer layer remains in the hadronic phase, because the conversion front stops when it reaches conditions under which the combustion is no longer exothermic.

  8. Limestone calcination during pulsating combustion

    SciTech Connect (OSTI)

    James, R.E. III (Oak Ridge Associated Universities, Inc., TN (United States)); Richards, G.A. (USDOE Morgantown Energy Technology Center, WV (United States))

    1992-01-01

    METC is currently conducting research on enhanced calcination during pulsating combustion as part of the Heat Engines program. It has been shown elsewhere that rapid, high temperature calcination will result in a calcined product with relatively large surface area, as desired for sulfur capture. It is proposed that such a process may occur during pulsating combustion where the oscillating pressure/velocity field around a particle increases the heat/mass transfer to and from the particle. To test this hypothesis, calcination tests in progress at METC use a novel form of pulse combustion called thermal'' pulse combustion, operating at 60000 BTUH, 100 Hz, and 5--15 psig peak-to- peak amplitude. Two configurations are being studied during the testing: one configuration is injection of sorbent into a refractory lined drop tube being heated by the pulse combustor, and the other configuration is injection of the sorbent into the pulse combustor through its centerbody and along the tailpipe at various positions. To understand the observed behavior, a characterization study of the pulse combustor is being conducted. Different flow rates, equivalence ratios, and injection positions are being tested.

  9. Structural Analysis of Combustion Models

    E-Print Network [OSTI]

    Tóth, J; Zsély, I

    2013-01-01

    Using ReactionKinetics, a Mathematica based package a few dozen detailed models for combustion of hydrogen, carbon monoxide and methanol are investigated. Essential structural characteristics are pulled out, and similarities and differences of the mechanisms are highlighted. These investigations can be used before or parallel with usual numerical investigations, such as pathway analysis, sensitivity analysis, parameter estimation, or simulation.

  10. The Effect of Magnetic Turbulence Energy Spectral

    E-Print Network [OSTI]

    Ng, Chung-Sang

    The Effect of Magnetic Turbulence Energy Spectral Scaling on the Heating of the Solar Wind C. S. Ng), Kraichnan (1965) #12;Solar wind turbulence model The steady state solar wind turbulence model developed wind with uniform speed Vsw 1D (radial position r) Turbulence characterized by two fields

  11. Measurement of Turbulent Flame Speeds of Hydrogen and Natural Gas Blends (C1-C5 Alkanes) using a Newly Developed Fan-Stirred Vessel 

    E-Print Network [OSTI]

    Ravi, Sankaranarayana

    2014-05-06

    A fan-stirred flame speed vessel was developed at Texas A&M University to conduct turbulent combustion studies. Four high-speed impellers were installed in a central-symmetric pattern at the central circumference of an existing cylindrical laminar...

  12. Effects of primary breakup modeling on spray and combustion characteristics of compression ignition engines

    SciTech Connect (OSTI)

    Som, S.; Aggarwal, S.K. [Department of Mechanical and Industrial Engineering, University of Illinois at Chicago, Chicago, IL 60607 (United States)

    2010-06-15

    Injector flow dynamics and primary breakup processes are known to play a pivotal role in determining combustion and emissions in diesel engines. In the present study, we examine the effects of primary breakup modeling on the spray and combustion characteristics under diesel engine conditions. The commonly used KH model, which considers the aerodynamically induced breakup based on the Kelvin-Helmholtz instability, is modified to include the effects of cavitation and turbulence generated inside the injector. The KH model and the new (KH-ACT) model are extensively evaluated by performing 3-D time-dependent simulations with detailed chemistry under diesel engine conditions. Results indicate that the inclusion of cavitation and turbulence enhances primary breakup, leading to smaller droplet sizes, decrease in liquid penetration, and increase in the radial dispersion of spray. Predictions are compared with measurements for non-evaporating and evaporating sprays, as well as with flame measurements. While both the models are able to reproduce the experimentally observed global spray and combustion characteristics, predictions using the KH-ACT model exhibit closer agreement with measurements in terms of liquid penetration, cone angle, spray axial velocity, and liquid mass distribution for non-evaporating sprays. Similarly, the KH-ACT model leads to better agreement with respect to the liquid length and vapor penetration distance for evaporating sprays, and with respect to the flame lift-off location for combusting sprays. The improved agreement is attributed to the ability of the new model to account for the effects of turbulence and cavitation generated inside the injector, which enhance the primary breakup. Results further indicate that the combustion under diesel engine conditions is characterized by a double-flame structure with a rich premixed reaction zone near the flame stabilization region and a non-premixed reaction zone further downstream. This flame structure is consistent with the Dec's model for diesel engine combustion (Dec, 1997), and well captured by a newly developed flame index based on the scalar product of CO and O{sub 2} mass fraction gradients. (author)

  13. Memory effects in turbulent transport

    E-Print Network [OSTI]

    Alexander Hubbard; Axel Brandenburg

    2009-11-13

    In the mean-field theory of magnetic fields, turbulent transport, i.e. the turbulent electromotive force, is described by a combination of the alpha effect and turbulent magnetic diffusion, which are usually assumed to be proportional respectively to the mean field and its spatial derivatives. For a passive scalar there is just turbulent diffusion, where the mean flux of concentration depends on the gradient of the mean concentration. However, these proportionalities are approximations that are valid only if the mean field or the mean concentration vary slowly in time. Examples are presented where turbulent transport possesses memory, i.e. where it depends crucially on the past history of the mean field. Such effects are captured by replacing turbulent transport coefficients with time integral kernels, resulting in transport coefficients that depend effectively on the frequency or the growth rate of the mean field itself. In this paper we perform numerical experiments to find the characteristic timescale (or memory length) of this effect as well as simple analytical models of the integral kernels in the case of passive scalar concentrations and kinematic dynamos. The integral kernels can then be used to find self-consistent growth or decay rates of the mean fields. In mean-field dynamos the growth rates and cycle periods based on steady state values of alpha effect and turbulent diffusivity can be quite different from the actual values.

  14. Compound cooling flow turbulator for turbine component

    DOE Patents [OSTI]

    Lee, Ching-Pang; Jiang, Nan; Marra, John J; Rudolph, Ronald J

    2014-11-25

    Multi-scale turbulation features, including first turbulators (46, 48) on a cooling surface (44), and smaller turbulators (52, 54, 58, 62) on the first turbulators. The first turbulators may be formed between larger turbulators (50). The first turbulators may be alternating ridges (46) and valleys (48). The smaller turbulators may be concave surface features such as dimples (62) and grooves (54), and/or convex surface features such as bumps (58) and smaller ridges (52). An embodiment with convex turbulators (52, 58) in the valleys (48) and concave turbulators (54, 62) on the ridges (46) increases the cooling surface area, reduces boundary layer separation, avoids coolant shadowing and stagnation, and reduces component mass.

  15. Modeling of Laser-Induced Metal Combustion

    SciTech Connect (OSTI)

    Boley, C D; Rubenchik, A M

    2008-02-20

    Experiments involving the interaction of a high-power laser beam with metal targets demonstrate that combustion plays an important role. This process depends on reactions within an oxide layer, together with oxygenation and removal of this layer by the wind. We present an analytical model of laser-induced combustion. The model predicts the threshold for initiation of combustion, the growth of the combustion layer with time, and the threshold for self-supported combustion. Solutions are compared with detailed numerical modeling as benchmarked by laboratory experiments.

  16. Method of combustion for dual fuel engine

    DOE Patents [OSTI]

    Hsu, B.D.; Confer, G.L.; Zujing Shen; Hapeman, M.J.; Flynn, P.L.

    1993-12-21

    Apparatus and a method of introducing a primary fuel, which may be a coal water slurry, and a high combustion auxiliary fuel, which may be a conventional diesel oil, into an internal combustion diesel engine comprises detecting the load conditions of the engine, determining the amount of time prior to the top dead center position of the piston to inject the main fuel into the combustion chamber, and determining the relationship of the timing of the injection of the auxiliary fuel into the combustion chamber to achieve a predetermined specific fuel consumption, a predetermined combustion efficiency, and a predetermined peak cylinder firing pressure. 19 figures.

  17. Method of combustion for dual fuel engine

    DOE Patents [OSTI]

    Hsu, Bertrand D. (Erie, PA); Confer, Gregory L. (Erie, PA); Shen, Zujing (Erie, PA); Hapeman, Martin J. (Edinboro, PA); Flynn, Paul L. (Fairview, PA)

    1993-12-21

    Apparatus and a method of introducing a primary fuel, which may be a coal water slutty, and a high combustion auxiliary fuel, which may be a conventional diesel oil, into an internal combustion diesel engine comprises detecting the load conditions of the engine, determining the amount of time prior to the top dead center position of the piston to inject the main fuel into the combustion chamber, and determining the relationship of the timing of the injection of the auxiliary fuel into the combustion chamber to achieve a predetermined specific fuel consumption, a predetermined combustion efficiency, and a predetermined peak cylinder firing pressure.

  18. Wave Decay in MHD Turbulence

    E-Print Network [OSTI]

    Andrey Beresnyak; Alex Lazarian

    2008-05-06

    We present a model for nonlinear decay of the weak wave in three-dimensional incompressible magnetohydrodynamic (MHD) turbulence. We show that the decay rate is different for parallel and perpendicular waves. We provide a general formula for arbitrarily directed waves and discuss particular limiting cases known in the literature. We test our predictions with direct numerical simulations of wave decay in three-dimensional MHD turbulence, and discuss the influence of turbulent damping on the development of linear instabilities in the interstellar medium and on other important astrophysical processes.

  19. Combustion diagnostic for active engine feedback control

    DOE Patents [OSTI]

    Green, Jr., Johney Boyd (Knoxville, TN); Daw, Charles Stuart (Knoxville, TN); Wagner, Robert Milton (Knoxville, TN)

    2007-10-02

    This invention detects the crank angle location where combustion switches from premixed to diffusion, referred to as the transition index, and uses that location to define integration limits that measure the portions of heat released during the combustion process that occur during the premixed and diffusion phases. Those integrated premixed and diffusion values are used to develop a metric referred to as the combustion index. The combustion index is defined as the integrated diffusion contribution divided by the integrated premixed contribution. As the EGR rate is increased enough to enter the low temperature combustion regime, PM emissions decrease because more of the combustion process is occurring over the premixed portion of the heat release rate profile and the diffusion portion has been significantly reduced. This information is used to detect when the engine is or is not operating in a low temperature combustion mode and provides that feedback to an engine control algorithm.

  20. Light Duty Efficient, Clean Combustion

    SciTech Connect (OSTI)

    Donald Stanton

    2010-12-31

    Cummins has successfully completed the Light Duty Efficient Clean Combustion (LDECC) cooperative program with DoE. This program was established in 2007 in support of the Department of Energy's Vehicles Technologies Advanced Combustion and Emissions Control initiative to remove critical barriers to the commercialization of advanced, high efficiency, emissions compliant internal combustion (IC) engines for light duty vehicles. Work in this area expanded the fundamental knowledge of engine combustion to new regimes and advanced the knowledge of fuel requirements for these diesel engines to realize their full potential. All of the following objectives were met with fuel efficiency improvement targets exceeded: (1) Improve light duty vehicle (5000 lb. test weight) fuel efficiency by 10.5% over today's state-of-the-art diesel engine on the FTP city drive cycle; (2) Develop and design an advanced combustion system plus aftertreatment system that synergistically meets Tier 2 Bin 5 NOx and PM emissions standards while demonstrating the efficiency improvements; (3) Maintain power density comparable to that of current conventional engines for the applicable vehicle class; and (4) Evaluate different fuel components and ensure combustion system compatibility with commercially available biofuels. Key accomplishments include: (1) A 25% improvement in fuel efficiency was achieved with the advanced LDECC engine equipped with a novel SCR aftertreatment system compared to the 10.5% target; (2) An 11% improvement in fuel efficiency was achieved with the advanced LDECC engine and no NOx aftertreamtent system; (3) Tier 2 Bin 5 and SFTP II emissions regulations were met with the advanced LDECC engine equipped with a novel SCR aftertreatment system; (4) Tier 2 Bin 5 emissions regulations were met with the advanced LDECC engine and no NOx aftertreatment, but SFTP II emissions regulations were not met for the US06 test cycle - Additional technical barriers exist for the no NOx aftertreatment engine; (5) Emissions and efficiency targets were reached with the use of biodiesel. A variety of biofuel feedstocks (soy, rapeseed, etc.) was investigated; (6) The advanced LDECC engine with low temperature combustion was compatible with commercially available biofuels as evaluated by engine performance testing and not durability testing; (7) The advanced LDECC engine equipped with a novel SCR aftertreatment system is the engine system architecture that is being further developed by the Cummins product development organization. Cost reduction and system robustness activities have been identified for future deployment; (8) The new engine and aftertreatment component technologies are being developed by the Cummins Component Business units (e.g. fuel system, turbomachinery, aftertreatment, electronics, etc.) to ensure commercial viability and deployment; (9) Cummins has demonstrated that the technologies developed for this program are scalable across the complete light duty engine product offerings (2.8L to 6.7L engines); and (10) Key subsystems developed include - sequential two stage turbo, combustions system for low temperature combustion, novel SCR aftertreatment system with feedback control, and high pressure common rail fuel system. An important element of the success of this project was leveraging Cummins engine component technologies. Innovation in component technology coupled with system integration is enabling Cummins to move forward with the development of high efficiency clean diesel products with a long term goal of reaching a 40% improvement in thermal efficiency for the engine plus aftertreatment system. The 40% improvement is in-line with the current light duty vehicle efficiency targets set by the 2010 DoE Vehicle Technologies MYPP and supported through co-operative projects such as the Cummins Advanced Technology Powertrains for Light-Duty Vehicles (ATP-LD) started in 2010.

  1. Light Duty Efficient, Clean Combustion

    SciTech Connect (OSTI)

    Stanton, Donald W

    2011-06-03

    Cummins has successfully completed the Light Duty Efficient Clean Combustion (LDECC) cooperative program with DoE. This program was established in 2007 in support of the Department of Energy’s Vehicles Technologies Advanced Combustion and Emissions Control initiative to remove critical barriers to the commercialization of advanced, high efficiency, emissions compliant internal combustion (IC) engines for light duty vehicles. Work in this area expanded the fundamental knowledge of engine combustion to new regimes and advanced the knowledge of fuel requirements for these diesel engines to realize their full potential. All of the following objectives were met with fuel efficiency improvement targets exceeded: 1. Improve light duty vehicle (5000 lb. test weight) fuel efficiency by 10.5% over today’s state-ofthe- art diesel engine on the FTP city drive cycle 2. Develop & design an advanced combustion system plus aftertreatment system that synergistically meets Tier 2 Bin 5 NOx and PM emissions standards while demonstrating the efficiency improvements. 3. Maintain power density comparable to that of current conventional engines for the applicable vehicle class. 4. Evaluate different fuel components and ensure combustion system compatibility with commercially available biofuels. Key accomplishments include: ? A 25% improvement in fuel efficiency was achieved with the advanced LDECC engine equipped with a novel SCR aftertreatment system compared to the 10.5% target ? An 11% improvement in fuel efficiency was achieved with the advanced LDECC engine and no NOx aftertreamtent system ? Tier 2 Bin 5 and SFTP II emissions regulations were met with the advanced LDECC engine equipped with a novel SCR aftertreatment system ? Tier 2 Bin 5 emissions regulations were met with the advanced LDECC engine and no NOx aftertreatment, but SFTP II emissions regulations were not met for the US06 test cycle – Additional technical barriers exist for the no NOx aftertreatment engine ? Emissions and efficiency targets were reached with the use of biodiesel. A variety of biofuel feedstocks (soy, rapeseed, etc.) was investigated. ? The advanced LDECC engine with low temperature combustion was compatible with commercially available biofuels as evaluated by engine performance testing and not durability testing. ? The advanced LDECC engine equipped with a novel SCR aftertreatment system is the engine system architecture that is being further developed by the Cummins product development organization. Cost reduction and system robustness activities have been identified for future deployment. ? The new engine and aftertreatment component technologies are being developed by the Cummins Component Business units (e.g. fuel system, turbomachinery, aftertreatment, electronics, etc.) to ensure commercial viability and deployment ? Cummins has demonstrated that the technologies developed for this program are scalable across the complete light duty engine product offerings (2.8L to 6.7L engines) ? Key subsystems developed include – sequential two stage turbo, combustions system for low temperature combustion, novel SCR aftertreatment system with feedback control, and high pressure common rail fuel system An important element of the success of this project was leveraging Cummins engine component technologies. Innovation in component technology coupled with system integration is enabling Cummins to move forward with the development of high efficiency clean diesel products with a long term goal of reaching a 40% improvement in thermal efficiency for the engine plus aftertreatment system. The 40% improvement is in-line with the current light duty vehicle efficiency targets set by the 2010 DoE Vehicle Technologies MYPP and supported through co-operative projects such as the Cummins Advanced Technology Powertrains for Light- Duty Vehicles (ATP-LD) started in 2010.

  2. Assessment of reduced mechanisms using One Dimensional Stochastic Turbulence model

    E-Print Network [OSTI]

    Chien, Li-Chun

    2010-01-01

    as internal combustion engines, gas turbine engines, andstabilized combustion zone in aircraft gas turbines. If thegas turbines burning natural gas, lean premixed combustion

  3. Investigation of the effect of chemistry models on the numerical predictions of the supersonic combustion of hydrogen

    SciTech Connect (OSTI)

    Kumaran, K.; Babu, V.

    2009-04-15

    In this numerical study, the influence of chemistry models on the predictions of supersonic combustion in a model combustor is investigated. To this end, 3D, compressible, turbulent, reacting flow calculations with a detailed chemistry model (with 37 reactions and 9 species) and the Spalart-Allmaras turbulence model have been carried out. These results are compared with earlier results obtained using single step chemistry. Hydrogen is used as the fuel and three fuel injection schemes, namely, strut, staged (i.e., strut and wall) and wall injection, are considered to evaluate the impact of the chemistry models on the flow field predictions. Predictions of the mass fractions of major species, minor species, dimensionless stagnation temperature, dimensionless static pressure rise and thrust percentage along the combustor length are presented and discussed. Overall performance metrics such as mixing efficiency and combustion efficiency are used to draw inferences on the nature (whether mixing- or kinetic-controlled) and the completeness of the combustion process. The predicted values of the dimensionless wall static pressure are compared with experimental data reported in the literature. The calculations show that multi step chemistry predicts higher and more wide spread heat release than what is predicted by single step chemistry. In addition, it is also shown that multi step chemistry predicts intricate details of the combustion process such as the ignition distance and induction distance. (author)

  4. Level set simulations of turbulent thermonuclear deflagration in degenerate carbon and oxygen

    E-Print Network [OSTI]

    W. Schmidt; W. Hillebrandt; J. C. Niemeyer

    2005-08-02

    We study the dynamics of thermonuclear flames propagating in fuel stirred by stochastic forcing. The fuel consists of carbon and oxygen in a state which is encountered in white dwarfs close to the Chandrasekhar limit. The level set method is applied to represent the flame fronts numerically. The computational domain for the numerical simulations is cubic, and periodic boundary conditions are imposed. The goal is the development of a suitable flame speed model for the small-scale dynamics of turbulent deflagration in thermonuclear supernovae. Because the burning process in a supernova explosion is transient and spatially inhomogeneous, the localised determination of subgrid scale closure parameters is essential. We formulate a semi-localised model based on the dynamical equation for the subgrid scale turbulence energy $k_{\\mathrm{sgs}}$. The turbulent flame speed $s_{\\mathrm{t}}$ is of the order $\\sqrt{2k_{\\mathrm{sgs}}}$. In particular, the subgrid scale model features a dynamic procedure for the calculation of the turbulent energy transfer from resolved toward subgrid scales, which has been successfully applied to combustion problems in engineering. The options of either including or suppressing inverse energy transfer in the turbulence production term are compared. In combination with the piece-wise parabolic method for the hydrodynamics, our results favour the latter option. Moreover, different choices for the constant of proportionality in the asymptotic flame speed relation, $s_{\\mathrm{t}}\\propto\\sqrt{2k_{\\mathrm{sgs}}}$, are investigated.

  5. CFD Analysis of Nuclear Fuel Bundles and Spacer Grids for PWR Reactors 

    E-Print Network [OSTI]

    Capone, Luigi

    2012-10-19

    The analysis of the turbulent flows in nuclear fuel bundles is a very interesting task to optimize the efficiency of modern nuclear power plants. The proposed study utilizes Computational Fluid Dynamics (CFD) to characterize the flow pattern...

  6. Low Temperature Combustion Demonstrator for High Efficiency Clean Combustion

    SciTech Connect (OSTI)

    Ojeda, William de

    2010-07-31

    The project which extended from November 2005 to May of 2010 demonstrated the application of Low Temperature Combustion (LTC) with engine out NOx levels of 0.2 g/bhp-hr throughout the program target load of 12.6bar BMEP. The project showed that the range of loads could be extended to 16.5bar BMEP, therefore matching the reference lug line of the base 2007 MY Navistar 6.4L V8 engine. Results showed that the application of LTC provided a dramatic improvement over engine out emissions when compared to the base engine. Furthermore LTC improved thermal efficiency by over 5% from the base production engine when using the steady state 13 mode composite test as a benchmark. The key enablers included improvements in the air, fuel injection, and cooling systems made in Phases I and II. The outcome was the product of a careful integration of each component under an intelligent control system. The engine hardware provided the conditions to support LTC and the controller provided the necessary robustness for a stable combustion. Phase III provided a detailed account on the injection strategy used to meet the high load requirements. During this phase, the control strategy was implemented in a production automotive grade ECU to perform cycle-by-cycle combustion feedback on each of the engine cylinders. The control interacted on a cycle base with the injection system and with the Turbo-EGR systems according to their respective time constants. The result was a unique system that could, first, help optimize the combustion system and maintain high efficiency, and secondly, extend the steady state results to the transient mode of operation. The engine was upgraded in Phase IV with a Variable Valve Actuation system and a hybrid EGR loop. The impact of the more versatile EGR loop did not provide significant advantages, however the application of VVA proved to be an enabler to further extend the operation of LTC and gain considerable benefits in fuel economy and soot reduction. Finally, the transient demonstration was performed in Phase IV. The project demonstrated the achievement of meeting US10 emissions without NOx aftertreatment. The successful execution of the project has served to highlight the effectiveness of closely matched combustion predictive tools to engine testing. It has further served to highlight the importance of key technologies and future areas of research and development. In this regard, recommendations are made towards further improvements in the areas of engine hardware, fuel injection systems, controls and fuels.

  7. Emissions of trace gases and aerosols during the open combustion of biomass in the laboratory

    E-Print Network [OSTI]

    McMeeking, Gavin R.

    2009-01-01

    mercury emissions during biomass combustion: Controllingin biomass smoke from residential wood combustion: Emissions1997), Emissions from smoldering combustion of biomass

  8. Determination of temperature and concentration from radiometric measurements in combustion systems

    E-Print Network [OSTI]

    Ren, Tao

    2015-01-01

    vii Spectral Bands for Combustion Gases . . . . . .Spectral Bands for Combustion Gases . . . . . . . . . 1.1.3for combustion gases . . . . . . . . . . . . . . . .

  9. Combustion synthesis continuous flow reactor

    DOE Patents [OSTI]

    Maupin, G.D.; Chick, L.A.; Kurosky, R.P.

    1998-01-06

    The present invention is a reactor for combustion synthesis of inorganic powders. The reactor includes a reaction vessel having a length and a first end and a second end. The reaction vessel further has a solution inlet and a carrier gas inlet. The reactor further has a heater for heating both the solution and the carrier gas. In a preferred embodiment, the reaction vessel is heated and the solution is in contact with the heated reaction vessel. It is further preferred that the reaction vessel be cylindrical and that the carrier gas is introduced tangentially into the reaction vessel so that the solution flows helically along the interior wall of the reaction vessel. As the solution evaporates and combustion produces inorganic material powder, the carrier gas entrains the powder and carries it out of the reactor. 10 figs.

  10. Internal combustion engine fuel feed

    SciTech Connect (OSTI)

    Cochard, P.; Guicherd, C.

    1980-02-19

    In a method and apparatus for controlling the fuel feed to a stratified-charge internal combustion engine, from idle up to the position corresponding with the maximum flow of air, the overall richness (Rg) of the combustible mixture is reduced by acting simultaneously upon the flow of fuel feeding the main chamber and upon the flow of fuel injected into the auxiliary chamber. For higher loads the maximum flow of air is kept constant and rg is increased by continuing to act upon both fuel flows. By keeping the richness of the mixture in the auxiliary chamber substantially constant, it is possible to obtain the best compromise between the performance of the engine and the emission of pollutant gases.

  11. Coal combustion by wet oxidation

    SciTech Connect (OSTI)

    Bettinger, J.A.; Lamparter, R.A.; McDowell, D.C.

    1980-11-15

    The combustion of coal by wet oxidation was studied by the Center for Waste Management Programs, of Michigan Technological University. In wet oxidation a combustible material, such as coal, is reacted with oxygen in the presence of liquid water. The reaction is typically carried out in the range of 204/sup 0/C (400/sup 0/F) to 353/sup 0/C (650/sup 0/F) with sufficient pressure to maintain the water present in the liquid state, and provide the partial pressure of oxygen in the gas phase necessary to carry out the reaction. Experimental studies to explore the key reaction parameters of temperature, time, oxidant, catalyst, coal type, and mesh size were conducted by running batch tests in a one-gallon stirred autoclave. The factors exhibiting the greatest effect on the extent of reaction were temperature and residence time. The effect of temperature was studied from 204/sup 0/C (400/sup 0/F) to 260/sup 0/C (500/sup 0/F) with a residence time from 600 to 3600 seconds. From this data, the reaction activation energy of 2.7 x 10/sup 4/ calories per mole was determined for a high-volatile-A-Bituminous type coal. The reaction rate constant may be determined at any temperature from the activation energy using the Arrhenius equation. Additional data were generated on the effect of mesh size and different coal types. A sample of peat was also tested. Two catalysts were evaluated, and their effects on reaction rate presented in the report. In addition to the high temperature combustion, low temperature desulfurization is discussed. Desulfurization can improve low grade coal to be used in conventional combustion methods. It was found that 90% of the sulfur can be removed from the coal by wet oxidation with the carbon untouched. Further desulfurization studies are indicated.

  12. Homogeneous catalysts in hypersonic combustion

    SciTech Connect (OSTI)

    Harradine, D.M.; Lyman, J.L.; Oldenborg, R.C.; Pack, R.T.; Schott, G.L.

    1989-01-01

    Density and residence time both become unfavorably small for efficient combustion of hydrogen fuel in ramjet propulsion in air at high altitude and hypersonic speed. Raising the density and increasing the transit time of the air through the engine necessitates stronger contraction of the air flow area. This enhances the kinetic and thermodynamic tendency of H/sub 2/O to form completely, accompanied only by N/sub 2/ and any excess H/sub 2/(or O/sub 2/). The by-products to be avoided are the energetically expensive fragment species H and/or O atoms and OH radicals, and residual (2H/sub 2/ plus O/sub 2/). However, excessive area contraction raises air temperature and consequent combustion-product temperature by adiabatic compression. This counteracts and ultimately overwhelms the thermodynamic benefit by which higher density favors the triatomic product, H/sub 2/O, over its monatomic and diatomic alternatives. For static pressures in the neighborhood of 1 atm, static temperature must be kept or brought below ca. 2400 K for acceptable stability of H/sub 2/O. Another measure, whose requisite chemistry we address here, is to extract propulsive work from the combustion products early in the expansion. The objective is to lower the static temperature of the combustion stream enough for H/sub 2/O to become adequately stable before the exhaust flow is massively expanded and its composition ''frozen.'' We proceed to address this mechanism and its kinetics, and then examine prospects for enhancing its rate by homogeneous catalysts. 9 refs.

  13. Pulsed atmospheric fluidized bed combustion

    SciTech Connect (OSTI)

    Not Available

    1992-05-01

    During this first quarter, a lab-scale water-cooled pulse combustor was designed, fabricated, and integrated with old pilot-scale PAFBC test systems. Characterization tests on this pulse combustor firing different kinds of fuel -- natural gas, pulverized coal and fine coal -- were conducted (without fluidized bed operation) for the purpose of finalizing PAFBC full-scale design. Steady-state tests were performed. Heat transfer performance and combustion efficiency of a coal-fired pulse combustor were evaluated.

  14. Fuel-air mixing and combustion in a two-dimensional Wankel engine

    SciTech Connect (OSTI)

    Shih, T.I.P.; Schock, H.J.; Ramos, J.I.

    1987-01-01

    The effects of mixture stratification at the intake port and gaseous fuel injection on the flow field and fuel-air mixing in a two-dimensional rotary engine model have been investigated by means of a two-equation model of turbulence, an algebraic grid generation method and an approximate factorization time-linearized numerical technique. It is shown that the fuel distribution in the combustion chamber is a function of the air-fuel mixture fluctuations at the intake port. The fuel is advected by the flow field induced by the rotor and is concentrated near the leading apex during the intake stroke. During compression, the fuel concentration is highest near the trailing apex and lowest near the rotor. The penetration of gaseous fuel injected into the combustion chamber during the compression stroke increases with the injection velocity.

  15. Method and apparatus for active control of combustion rate through modulation of heat transfer from the combustion chamber wall

    DOE Patents [OSTI]

    Roberts, Jr., Charles E.; Chadwell, Christopher J.

    2004-09-21

    The flame propagation rate resulting from a combustion event in the combustion chamber of an internal combustion engine is controlled by modulation of the heat transfer from the combustion flame to the combustion chamber walls. In one embodiment, heat transfer from the combustion flame to the combustion chamber walls is mechanically modulated by a movable member that is inserted into, or withdrawn from, the combustion chamber thereby changing the shape of the combustion chamber and the combustion chamber wall surface area. In another embodiment, heat transfer from the combustion flame to the combustion chamber walls is modulated by cooling the surface of a portion of the combustion chamber wall that is in close proximity to the area of the combustion chamber where flame speed control is desired.

  16. TOXIC SUBSTANCES FROM COAL COMBUSTION

    SciTech Connect (OSTI)

    Kolker, A.; Sarofim, A.F.; Palmer, C.A.; Huggins, F.E.; Huffman, G.P.; Lighty, J.; Veranth, J.; Helble, J.J.; Wendt, J.O.L.; Ames, M.R.; Finkelman, R.; Mamani-Paco, M.; Sterling, R.; Mroczkowsky, S.J.; Panagiotou, T.; Seames, W.

    1999-05-10

    The Clean Air Act Amendments of 1990 identify a number of hazardous air pollutants (HAPs) as candidates for regulation. Should regulations be imposed on HAP emissions from coal-fired power plants, a sound understanding of the fundamental principles controlling the formation and partitioning of toxic species during coal combustion will be needed. With support from the Federal Energy Technology Center (FETC), the Electric Power Research Institute, and VTT (Finland), Physical Sciences Inc. (PSI) has teamed with researchers from USGS, MIT, the University of Arizona (UA), the University of Kentucky (UK), the University of Connecticut (UC), the University of Utah (UU) and the University of North Dakota Energy and Environ-mental Research Center (EERC) to develop a broadly applicable emissions model useful to regulators and utility planners. The new Toxics Partitioning Engineering Model (ToPEM) will be applicable to all combustion conditions including new fuels and coal blends, low-NOx combustion systems, and new power generation plants. Development of ToPEM will be based on PSI's existing Engineering Model for Ash Formation (EMAF). This report covers the reporting period from 1 January 1999 to 31 March 1999. During this period, a full Program Review Meeting was held at the University of Arizona. At this meeting, the progress of each group was reviewed, plans for the following 9 month period were discussed, and action items (principally associated with the transfer of samples and reports among the various investigators) were identified.

  17. LES SOFTWARE FOR THE DESIGN OF LOW EMISSION COMBUSTION SYSTEMS FOR VISION 21 PLANTS

    SciTech Connect (OSTI)

    Steve Cannon; Baifang Zuo; Virgil Adumitroaie; Keith McDaniel; Cliff Smith

    2002-01-01

    Further development of a combustion Large Eddy Simulation (LES) code for the design of advanced gaseous combustion systems is described in this fifth quarterly report. CFD Research Corporation (CFDRC) is developing the LES module within the parallel, unstructured solver included in the commercial CFD-ACE+ software. In this quarter, in-situ adaptive tabulation (ISAT) for efficient chemical rate storage and retrieval was further tested in the LES code. The use of multiple trees and periodic tree dumping was investigated. Implementation of the Linear Eddy Model (LEM) for subgrid chemistry was finished for serial applications. Validation of the model on a backstep reacting case was performed. Initial calculations of the SimVal experiment were performed for various barrel lengths, equivalence ratio, combustor shapes, and turbulence models. The effects of these variables on combustion instability was studied. Georgia Tech continues the effort to parameterize the LEM over composition space so that a neural net can be used efficiently in the combustion LES code. Next quarter, the 2nd consortium meeting will be held at CFDRC. LES software development and testing will continue. Alpha testing of the code will be performed on cases of interest to the industrial consortium. Optimization of subgrid models will be pursued, particularly with the ISAT approach. Also next quarter, the demonstration of the neural net approach, for chemical kinetics speed-up in CFD-ACE+, should be accomplished.

  18. Application of pulse combustion to solid and hazardous-waste incineration

    SciTech Connect (OSTI)

    Stewart, C.R.; Lemieux, P.M.; Zinn, B.T.

    1991-01-01

    The paper discusses the application of pulse combustion to solid and hazardous waste incineration. A rotary kiln incinerator simulator was retrofitted with a frequency-tunable pulse combustor to enhance the efficiency of combustion. The pulse combustor excites pulsations in the kiln and increases the completeness of combustion by promoting better mixing within the system. Tests were performed using toluene sorbed onto a ground corn cob sorbent and placed in cardboard containers. The burner was operated in a non-pulse mode as a baseline condition, and then in a pulse mode in which the frequency of the pulse combustor was adjusted to the natural frequency of the combustion chamber, creating resonant pulsations of large magnitude. The test was also performed using polyethylene tube bundles to simulate a solid waste and to investigate a surrogate which produces different puff characteristics. The addition of turbulence in the rotary kiln due to high amplitude acoustic pulsations has a strong tendency to reduce the amount of soot and/or semivolatile and non-volatile hydrocarbons. Mass emissions of soot were consistently reduced in all tests. Carbon monoxide increased during acoustic pulsations in the toluene tests. The paper also discusses unsatisfied oxygen demand and carbon penetration and how pulsations affect them.

  19. COMBUSTION RESEARCH Chapter from the Energy and Environment Division Annual Report 1980

    E-Print Network [OSTI]

    Authors, Various

    2013-01-01

    Heat Transfer with Combustion R. Greif, H. Heperkan, J.H. Stewart . • . • • . COMBUSTION CHEMISTRY AND POLLUTANTInternational) on Combustion, The Combustion institute,

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

    SciTech Connect (OSTI)

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

    2010-06-29

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

  1. Industrial Combustion Vision: A Vision by and for the Industrial Combustion Community

    SciTech Connect (OSTI)

    none,

    1998-05-01

    The Industrial Combustion Vision is the result of a collaborative effort by manufacturers and users of burners, boilers, furnaces, and other process heating equipment. The vision sets bold targets for tomorrow's combustion systems.

  2. Engine Valve Actuation For Combustion Enhancement

    DOE Patents [OSTI]

    Reitz, Rolf Deneys (Madison, WI); Rutland, Christopher J. (Madison, WI); Jhavar, Rahul (Madison, WI)

    2004-05-18

    A combustion chamber valve, such as an intake valve or an exhaust valve, is briefly opened during the compression and/or power strokes of a 4-stroke combustion cycle in an internal combustion engine (in particular, a diesel or CI engine). The brief opening may (1) enhance mixing withing the combustion chamber, allowing more complete oxidation of particulates to decrease engine emissions; and/or may (2) delay ignition until a more desirable time, potentially allowing a means of timing ignition in otherwise difficult-to-control conditions, e.g., in HCCI (Homogeneous Charge Compression Ignition) conditions.

  3. Researchers create successful predictions of combustion reaction...

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

    pressure-dependent chemical reaction rates, an important breakthrough in combustion and atmospheric chemistry that is expected to benefit auto and engine manufacturers, oil and...

  4. Engine valve actuation for combustion enhancement

    DOE Patents [OSTI]

    Reitz, Rolf Deneys (Madison, WI); Rutland, Christopher J. (Madison, WI); Jhavar, Rahul (Madison, WI)

    2008-03-04

    A combustion chamber valve, such as an intake valve or an exhaust valve, is briefly opened during the compression and/or power strokes of a 4-strokes combustion cycle in an internal combustion engine (in particular, a diesel or CI engine). The brief opening may (1) enhance mixing withing the combustion chamber, allowing more complete oxidation of particulates to decrease engine emissions; and/or may (2) delay ignition until a more desirable time, potentially allowing a means of timing ignition in otherwise difficult-to-control conditions, e.g., in HCCI (Homogeneous Charge Compression Ignition) conditions.

  5. Pyrolysis reactor and fluidized bed combustion chamber

    DOE Patents [OSTI]

    Green, Norman W. (Upland, CA)

    1981-01-06

    A solid carbonaceous material is pyrolyzed in a descending flow pyrolysis reactor in the presence of a particulate source of heat to yield a particulate carbon containing solid residue. The particulate source of heat is obtained by educting with a gaseous source of oxygen the particulate carbon containing solid residue from a fluidized bed into a first combustion zone coupled to a second combustion zone. A source of oxygen is introduced into the second combustion zone to oxidize carbon monoxide formed in the first combustion zone to heat the solid residue to the temperature of the particulate source of heat.

  6. A Generalized Pyrolysis Model for Combustible Solids

    E-Print Network [OSTI]

    Lautenberger, Chris

    2007-01-01

    combustion chemistry is not all that well understood, experimental data [212] for the spontaneous ignition delay time of a lean propane/

  7. Advancing Internal Combustion Engine Simulations using Sensitivity...

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

    Advancing Internal Combustion Engine Simulations using Sensitivity Analysis PI Name: Sibendu Som PI Email: ssom@anl.gov Institution: Argonne National Laboratory Allocation Program:...

  8. Combustion with reduced carbon in the ash

    DOE Patents [OSTI]

    Kobayashi, Hisashi; Bool, III, Lawrence E.

    2005-12-27

    Combustion of coal in which oxygen is injected into the coal as it emerges from burner produces ash having reduced amounts of carbon.

  9. A Generalized Pyrolysis Model for Combustible Solids

    E-Print Network [OSTI]

    Lautenberger, Chris

    2007-01-01

    fluid mechanics, heat transfer, radiation, and combustion toJ.R. , Thermal Radiation Heat Transfer . Third Edition,to account for radiation heat transfer across pores. The

  10. Effect of Turbulence Fluctuations on Surface Heating Rate in Hypersonic Turbulent

    E-Print Network [OSTI]

    Martín, Pino

    Effect of Turbulence Fluctuations on Surface Heating Rate in Hypersonic Turbulent Boundary Layers the effect of turbulence fluctuations on surface heating rate by conducting direct numerical simulations (DNS subtle influence on the mean heating rate. We also find that the effect of turbulence

  11. Effect of Finite-rate Chemical Reactions on Turbulence in Hypersonic Turbulent Boundary Layers

    E-Print Network [OSTI]

    Martín, Pino

    Effect of Finite-rate Chemical Reactions on Turbulence in Hypersonic Turbulent Boundary Layers Lian reaction. The influence of chemical reactions on temperature fluctuation variance, Reynolds stresses that the recombination reaction enhances turbulence, while the dissociation reaction damps turbulence. Chemical reactions

  12. Active skin for turbulent drag reduction 

    E-Print Network [OSTI]

    Mani, Raghavendran

    2002-01-01

    capitalizes on recent advances in active turbulent drag reduction and active material based actuation to develop an active or "smart" skin for turbulent drag reduction in realistic flight conditions. The skin operation principle is based on computational...

  13. Theoretical studies of combustion dynamics

    SciTech Connect (OSTI)

    Bowman, J.M. [Emory Univ., Atlanta, GA (United States)

    1993-12-01

    The basic objectives of this research program are to develop and apply theoretical techniques to fundamental dynamical processes of importance in gas-phase combustion. There are two major areas currently supported by this grant. One is reactive scattering of diatom-diatom systems, and the other is the dynamics of complex formation and decay based on L{sup 2} methods. In all of these studies, the authors focus on systems that are of interest experimentally, and for which potential energy surfaces based, at least in part, on ab initio calculations are available.

  14. Rotary reciprocating internal combustion engine

    SciTech Connect (OSTI)

    Ogren, W.

    1992-06-23

    This patent describes a rotary reciprocating internal combustion engine. It comprises a housing which comprises a cylindrical head with two end and frame plates mounted on both ends of the head enclose the head, the head including a pair of fuel into ports and a pair of exhaust ports, a pair of ring gears; a rotor axially aligned in the cylindrical head and comprising a set of four radially extending cylinders and pistons reciprocable in the cylinders; a power take off shaft fixed to the crank support plates and axially aligned with the rotor; oiling means for oiling the rotary engine; and a set of eight crank gears.

  15. Advanced Combustion | Argonne National Laboratory

    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 OutreachProductswsicloudwsicloudden DocumentationAccommodationsRegister /Advanced EnergyCombustion Advanced

  16. Time-resolved heat transfer in the oscillating turbulent flow of a pulse-combustor tail pipe

    SciTech Connect (OSTI)

    Dec, J.E.

    1988-01-01

    The need for efficient combustion systems has led to active research in pulse combustion. One advantage of pulse combustor heating systems is a high rate of heat transfer in the tail pipe. These high heat transfer rates result from large velocity oscillations, which occur in the tailpipe as a result of the acoustic resonance of the pulse combustor. Past research on the effects of flow oscillations on heat transfer rates is inconclusive; however, some oscillating turbulent flows have been shown to have Nusselt numbers, which are much higher than those to steady turbulent flow at the same mean Reynolds number. An experimental study of the heat transfer rates and convective transport processes in a pulse combustor tail pipe was conducted. A test combustor was used, in which the oscillation frequencies could be varied from 54 to 101 Hz, with peak-to-peak velocity oscillations from zero (steady flow) to 10 times the mean velocity, and mean Reynolds numbers from 3100 to 4750. Nusselt numbers in the tail pipe are enhanced by the oscillations up to a factor of 2.5 times the expected value for steady turbulent flow. The Nusselt number enhancement increases with both oscillation frequency and velocity oscillation amplitude. Increases in the mean Reynolds number decreased the enhancement. Possible causes for the heat-transfer enhancement in oscillating flows are discussed. The data indicate that the heat transfer enhancement results from a combination of increased turbulence intensity and transverse flows generated during the streamwise velocity reversals.

  17. Combustion and Magnetohydrodynamic Processes in Advanced Pulse Detonation Rocket Engines

    E-Print Network [OSTI]

    Cole, Lord Kahil

    2012-01-01

    Combustion and Magnetohydrodynamic Processes in Advanced PulseCombustion and Magnetohydrodynamic Processes in Advanced PulseCombustion Theory and Modeling, 9:159170, [16] Jean-Luc Cambier. Development of numerical tools for pulse

  18. An Energy Analysis of the Catalytic Combustion Burner 

    E-Print Network [OSTI]

    Dong, Q.; Zhang, S.; Duan, Z.; Zhou, Q.

    2006-01-01

    The gas boilers of conventional flame always produce varying degrees of combustion products NOx and CO, which pollute the environment and waste energy. As a new way of combustion, catalytic combustion breaks the flammable limits of conventional...

  19. The Measurement and Application of Electric Effects in Combustion

    E-Print Network [OSTI]

    Murphy, Daniel Corrigan

    2015-01-01

    radiation on a propane-air flame”. In: Combustion and Flameradiation on a propane-air flame”. In: Combustion and Flamein premixed propane–air flames”. In: Combustion and Flame

  20. Vehicle Technologies Office: 2011 Advanced Combustion R&D Annual...

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

    Combustion R&D Annual Progress Report Vehicle Technologies Office: 2011 Advanced Combustion R&D Annual Progress Report Annual report on the work of the the Advanced Combustion...

  1. AN EXPERIMENTAL AND THEORETICAL STUDY OF HEAT TRANSFER WITH COMBUSTION

    E-Print Network [OSTI]

    Heperkan, Hasan A.

    2013-01-01

    HDyna.mics of the Exothermic Process in Combustion,n 15thSymposium (International) on Combustion, Tokyo, 1974. H, S.Methods L Glassman, Combustion, Academic Press, 1977. D. J.

  2. Vehicle Technologies Office: 2009 Advanced Combustion R&D Annual...

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

    9 Advanced Combustion R&D Annual Progress Report Vehicle Technologies Office: 2009 Advanced Combustion R&D Annual Progress Report The Advanced Combustion Engine R&D subprogram...

  3. Numerical Study of a Turbulent Hydraulic Jump

    E-Print Network [OSTI]

    Zhao, Qun

    Numerical Study of a Turbulent Hydraulic Jump Qun Zhao, Shubhra Misra, Ib. A. Svendsen and James T of a Turbulent Hydraulic Jump ­ p.1/14 #12;Objective Our ultimate goal is to study the breaking waves. Numerical Study of a Turbulent Hydraulic Jump ­ p.2/14 #12;A moving bore Qiantang Bore China (Courtesy of Dr J

  4. Turbulence Induced Transport in Tokamaks

    SciTech Connect (OSTI)

    Caldas, I. L.; Marcus, F. A.; Heller, M. V. A. P.; Guimaraes-Filho, Z. O. [Instituto de Fisica, Universidade de Sao Paulo, Caixa Postal 66318, 05315-970, Sao Paulo, SP (Brazil); Batista, A. M. [Departamento de Matematica e Estatistica, Universidade Estadual de Ponta Grossa, Ponta Grossa, PR (Brazil); Viana, R. L.; Lopes, S. R. [Departamento de Fisica, Universidade Federal do Parana, 81531-990, Curitiba, PR (Brazil); Morrison, P. J.; Horton, W. [Department of Physics, University of Texas at Austin, Austin, Texas, 78712 (United States); Institute for Fusion Studies, The University of Texas at Austin, Austin, Texas, 78712 (United States)

    2006-12-04

    This report is concerned with plasma edge turbulence and its relation to anomalous particle transport in tokamaks. First, experimental evidence of turbulence driven particle transport and measurements of the gradients of the equilibrium profiles in the Brazilian tokamaks TBR and TCABR are presented. Next, diffusion in a two drift-wave system is discussed. In this nonintegrable system, particle transport is associated with the onset of chaotic orbits. Finally, numerical evidence suggesting that a nonlinear three-mode interaction could contribute to the intermittent plasma fluctuations observed in tokamaks is presented.

  5. Spatially resolved heat release rate measurements in turbulent premixed flames

    SciTech Connect (OSTI)

    Ayoola, B.O.; Kaminski, C.F.; Balachandran, R.; Mastorakos, E.; Frank, J.H.

    2006-01-01

    Heat release rate is a fundamental property of great importance for the theoretical and experimental elucidation of unsteady flame behaviors such as combustion noise, combustion instabilities, and pulsed combustion. Investigations of such thermoacoustic interactions require a reliable indicator of heat release rate capable of resolving spatial structures in turbulent flames. Traditionally, heat release rate has been estimated via OH or CH radical chemiluminescence; however, chemiluminescence suffers from being a line-of-sight technique with limited capability for resolving small-scale structures. In this paper, we report spatially resolved two-dimensional measurements of a quantity closely related to heat release rate. The diagnostic technique uses simultaneous OH and CH{sub 2}O planar laser-induced fluorescence (PLIF), and the pixel-by-pixel product of the OH and CH{sub 2}O PLIF signals has previously been shown to correlate well with local heat release rates. Results from this diagnostic technique, which we refer to as heat release rate imaging (HR imaging), are compared with traditional OH chemiluminescence measurements in several flames. Studies were performed in lean premixed ethylene flames stabilized between opposed jets and with a bluff body. Correlations between bulk strain rates and local heat release rates were obtained and the effects of curvature on heat release rate were investigated. The results show that the heat release rate tends to increase with increasing negative curvature for the flames investigated for which Lewis numbers are greater than unity. This correlation becomes more pronounced as the flame gets closer to global extinction.

  6. Gravitational Collapse in Turbulent Molecular Clouds. II. Magnetohydrodynamical Turbulence

    E-Print Network [OSTI]

    F. Heitsch; M. -M. Mac Low; R. S. Klessen

    2000-09-14

    Hydrodynamic supersonic turbulence can only prevent local gravitational collapse if the turbulence is driven on scales smaller than the local Jeans lengths in the densest regions, a very severe requirement (Paper I). Magnetic fields have been suggested to support molecular clouds either magnetostatically or via magnetohydrodynamic (MHD) waves. Whereas the first mechanism would form sheet-like clouds, the second mechanism not only could exert a pressure onto the gas counteracting the gravitational forces, but could lead to a transfer of turbulent kinetic energy down to smaller spatial scales via MHD wave interactions. This turbulent magnetic cascade might provide sufficient energy at small scales to halt local collapse. We test this hypothesis with MHD simulations at resolutions up to 256^3 zones, done with ZEUS-3D. We first derive a resolution criterion for self-gravitating, magnetized gas: in order to prevent collapse of magnetostatically supported regions due to numerical diffusion, the minimum Jeans length must be resolved by four zones. Resolution of MHD waves increases this requirement to roughly six zones. We then find that magnetic fields cannot prevent local collapse unless they provide magnetostatic support. Weaker magnetic fields do somewhat delay collapse and cause it to occur more uniformly across the supported region in comparison to the hydrodynamical case. However, they still cannot prevent local collapse for much longer than a global free-fall time.

  7. Simulating flame lift-off characteristics of diesel and biodiesel fuels using detailed chemical-kinetic mechanisms and LES turbulence model.

    SciTech Connect (OSTI)

    Som, S; Longman, D. E.; Luo, Z; Plomer, M; Lu, T; Senecal, P.K.; Pomraning, E (Energy Systems); (Univ. of Connecticut); (CONVERGENT Science)

    2012-01-01

    Combustion in direct-injection diesel engines occurs in a lifted, turbulent diffusion flame mode. Numerous studies indicate that the combustion and emissions in such engines are strongly influenced by the lifted flame characteristics, which are in turn determined by fuel and air mixing in the upstream region of the lifted flame, and consequently by the liquid breakup and spray development processes. From a numerical standpoint, these spray combustion processes depend heavily on the choice of underlying spray, combustion, and turbulence models. The present numerical study investigates the influence of different chemical kinetic mechanisms for diesel and biodiesel fuels, as well as Reynolds-averaged Navier-Stokes (RANS) and large eddy simulation (LES) turbulence models on predicting flame lift-off lengths (LOLs) and ignition delays. Specifically, two chemical kinetic mechanisms for n-heptane (NHPT) and three for biodiesel surrogates are investigated. In addition, the RNG k-{epsilon} (RANS) model is compared to the Smagorinsky based LES turbulence model. Using adaptive grid resolution, minimum grid sizes of 250 {micro}m and 125 {micro}m were obtained for the RANS and LES cases respectively. Validations of these models were performed against experimental data from Sandia National Laboratories in a constant volume combustion chamber. Ignition delay and flame lift-off validations were performed at different ambient temperature conditions. The LES model predicts lower ignition delays and qualitatively better flame structures compared to the RNG k-{epsilon} model. The use of realistic chemistry and a ternary surrogate mixture, which consists of methyl decanoate, methyl 9-decenoate, and NHPT, results in better predicted LOLs and ignition delays. For diesel fuel though, only marginal improvements are observed by using larger size mechanisms. However, these improved predictions come at a significant increase in computational cost.

  8. Method and system for controlled combustion engines

    DOE Patents [OSTI]

    Oppenheim, A. K. (Berkeley, CA)

    1990-01-01

    A system for controlling combustion in internal combustion engines of both the Diesel or Otto type, which relies on establishing fluid dynamic conditions and structures wherein fuel and air are entrained, mixed and caused to be ignited in the interior of a multiplicity of eddies, and where these structures are caused to sequentially fill the headspace of the cylinders.

  9. NETL- High-Pressure Combustion Research Facility

    SciTech Connect (OSTI)

    2013-07-08

    NETL's High-Pressure Combustion Facility is a unique resource within the National Laboratories system. It provides the test capabilities needed to evaluate new combustion concepts for high-pressure, high-temperature hydrogen and natural gas turbines. These concepts will be critical for the next generation of ultra clean, ultra efficient power systems.

  10. Sandia combustion research program: Annual report, 1987

    SciTech Connect (OSTI)

    Palmer, R.E.; Sanders, B.R.; Ivanetich, C.A.

    1988-01-01

    More than a decade ago, in response to a national energy crisis, Sandia proposed to the US Department of Energy a new, ambitious program in combustion research. Our strategy was to apply the rapidly increasing capabilities in lasers and computers to combustion science and technology. Shortly thereafter, the Combustion Research Facility (CRF) was established at Sandia's Livermore location. Designated a ''User Facility,'' the charter of the CRF was to develop and maintain special-purpose resources to support a nationwide initiative--involving US universities, industry, and national laboratories--to improve our understanding and control of combustion. This report includes descriptions of several research projects which have been stimulated by Working Groups and involve the on-site participation of industry scientists. DOE's Industry Technology Fellowship Program has been instrumental in the success of some of the joint efforts. The remainder of this report presents research results of calendar year 1987, separated thematically into nine categories. Refereed journal articles appearing in print during 1987, along with selected other publications, are included at the end of Section 10. In addition to our ''traditional'' research--chemistry, reacting flow, diagnostics, engine combustion, and coal combustion--you will note continued progress in somewhat recent themes: pulse combustion, high temperature materials, and energetic materials, for example. Moreover, we have just started a small, new effort to understand combustion-related issues in the management of toxic and hazardous materials.

  11. NETL- High-Pressure Combustion Research Facility

    ScienceCinema (OSTI)

    None

    2014-06-26

    NETL's High-Pressure Combustion Facility is a unique resource within the National Laboratories system. It provides the test capabilities needed to evaluate new combustion concepts for high-pressure, high-temperature hydrogen and natural gas turbines. These concepts will be critical for the next generation of ultra clean, ultra efficient power systems.

  12. Injector tip for an internal combustion engine

    DOE Patents [OSTI]

    Shyu, Tsu Pin; Ye, Wen

    2003-05-20

    This invention relates to a the tip structure of a fuel injector as used in a internal combustion engine. Internal combustion engines using Homogeneous Charge Compression Ignition (HCCI) technology require a tip structure that directs fuel spray in a downward direction. This requirement necessitates a tip design that is capable of withstanding mechanical stresses associated with the design.

  13. Coal slurry combustion and technology. Volume 2

    SciTech Connect (OSTI)

    Not Available

    1983-01-01

    Volume II contains papers presented at the following sessions of the Coal Slurry Combustion and Technology Symposium: (1) bench-scale testing; (2) pilot testing; (3) combustion; and (4) rheology and characterization. Thirty-three papers have been processed for inclusion in the Energy Data Base. (ATT)

  14. Fuel-Flexible Combustion System for Refinery and Chemical Plant...

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

    Flexible Combustion System for Refinery and Chemical Plant Process Heaters - Fact Sheet 2014 Fuel-Flexible Combustion System for Refinery and Chemical Plant Process Heaters - Fact...

  15. Sandia Energy - Heavy Duty Low-Temperature & Diesel Combustion

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

    reduce engine-out emissions. These approaches could allow advanced diesel combustion or low-temperature combustion strategies with potential for enabling both increased fuel...

  16. High Efficiency Clean Combustion for Heavy-Duty Engine

    Broader source: Energy.gov [DOE]

    Explore advancements in engine combustion systems using high-efficiency clean combustion (HECC) techniques to minimize engine-out emissions while optimizing fuel economy.

  17. Catalyst for Improving the Combustion Efficiency of Petroleum...

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

    for Improving the Combustion Efficiency of Petroleum Fuels in Diesel Engines Catalyst for Improving the Combustion Efficiency of Petroleum Fuels in Diesel Engines 2005 Diesel...

  18. A University Consortium on High Pressure, Lean Combustion for...

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

    High Pressure, Lean Combustion for Efficient and Clean IC Engines (UM - lead, MIT, UCB) A University Consortium on High Pressure, Lean Combustion for Efficient and Clean IC Engines...

  19. Computationally Efficient Modeling of High-Efficiency Clean Combustion...

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

    & Publications Computationally Efficient Modeling of High-Efficiency Clean Combustion Engines Computationally Efficient Modeling of High-Efficiency Clean Combustion Engines...

  20. Variable Valve Actuation for Advanced Mode Diesel Combustion...

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

    Valve Actuation for Advanced Mode Diesel Combustion Variable Valve Actuation for Advanced Mode Diesel Combustion Presentation from the U.S. DOE Office of Vehicle Technologies...

  1. Municipal Waste Combustion (New Mexico) | Department of Energy

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

    Municipal Waste Combustion (New Mexico) Municipal Waste Combustion (New Mexico) < Back Eligibility Investor-Owned Utility Local Government MunicipalPublic Utility Rural Electric...

  2. ¿Aceite vegetal puro como combustible diesel? (Straight Vegetable...

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

    sobre combustibles alternativos y vehculos de combustibles alternativos. El sitio web de la Oficina de Eficiencia Energtica y de Energa Renovable del DOE, www.eere....

  3. Vehicle Technologies Office: 2010 Advanced Combustion R&D Annual...

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

    Advanced Combustion R&D Annual Progress Report Vehicle Technologies Office: 2010 Advanced Combustion R&D Annual Progress Report 2010advcombustionengine.pdf More Documents &...

  4. Vehicle Technologies Office: 2008 Advanced Combustion R&D Annual...

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

    Advanced Combustion R&D Annual Progress Report Vehicle Technologies Office: 2008 Advanced Combustion R&D Annual Progress Report 2008advcombustionengine.pdf More Documents &...

  5. Unregulated Emissions from High-Efficiency Clean Combustion Modes...

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

    Unregulated Emissions from High-Efficiency Clean Combustion Modes - ORNL-FEERC Unregulated Emissions from High-Efficiency Clean Combustion Modes - ORNL-FEERC Poster presentation at...

  6. Characterization of Particulate Emissions from GDI Engine Combustion...

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

    Particulate Emissions from GDI Engine Combustion with Alcohol-blended Fuels Characterization of Particulate Emissions from GDI Engine Combustion with Alcohol-blended Fuels Analysis...

  7. Idling Emissions Reduction Technology with Low Temperature Combustion...

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

    Idling Emissions Reduction Technology with Low Temperature Combustion of DI Biodiesel and PFI n-Butanol Idling Emissions Reduction Technology with Low Temperature Combustion of DI...

  8. Development of Fuel-Flexible Combustion Systems Utilizing Opportunity...

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

    Fuel-Flexible Combustion Systems Utilizing Opportunity Fuels in Gas Turbines - Fact Sheet, May 2014 Development of Fuel-Flexible Combustion Systems Utilizing Opportunity Fuels in...

  9. Combustion Turbine CHP System for Food Processing Industry -...

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

    Combustion Turbine CHP System for Food Processing Industry - Presentation by Frito-Lay North America, June 2011 Combustion Turbine CHP System for Food Processing Industry -...

  10. Fuel Formulation Effects on Diesel Fuel Injection, Combustion...

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

    Formulation Effects on Diesel Fuel Injection, Combustion, Emissions and Emission Control Fuel Formulation Effects on Diesel Fuel Injection, Combustion, Emissions and Emission...

  11. A University Consortium on Low Temperature Combustion (LTC) for...

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

    Low Temperature Combustion (LTC) for High Efficiency, Ultra-Low Emission Engines A University Consortium on Low Temperature Combustion (LTC) for High Efficiency, Ultra-Low Emission...

  12. Building America Webinar: Solutions for Combustion Safety in...

    Office of Environmental Management (EM)

    Building America Webinar: Solutions for Combustion Safety in Existing Homes Building America Webinar: Solutions for Combustion Safety in Existing Homes December 16, 2015 3:00PM to...

  13. Hydrogen Assisted Diesel Combustion in a Common Rail Turbodiesel...

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

    Assisted Diesel Combustion in a Common Rail Turbodiesel Engine Hydrogen Assisted Diesel Combustion in a Common Rail Turbodiesel Engine This study measured the effects of hydrogen...

  14. Heavy-Duty Low Temperature Combustion Development Activities...

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

    Low Temperature Combustion Development Activities at Caterpillar Heavy-Duty Low Temperature Combustion Development Activities at Caterpillar Presentation given at the 2007 Diesel...

  15. Syngas Enhanced High Efficiency Low Temperature Combustion for...

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

    Enhanced High Efficiency Low Temperature Combustion for Clean Diesel Engines Syngas Enhanced High Efficiency Low Temperature Combustion for Clean Diesel Engines A significant...

  16. Vehicle Technologies Office: 2008 Advanced Combustion R&D Annual...

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

    Combustion R&D Annual Progress Report Vehicle Technologies Office: 2008 Advanced Combustion R&D Annual Progress Report 2008advcombustionengine.pdf More Documents & Publications...

  17. Demonstrating Optimum HCCI Combustion with Advanced Control Technology...

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

    Optimum HCCI Combustion with Advanced Control Technology Demonstrating Optimum HCCI Combustion with Advanced Control Technology Presentation given at the 2007 Diesel...

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

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

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

  19. Exploring Advanced Combustion Regimes for Efficiency and Emissions...

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

    Exploring Advanced Combustion Regimes for Efficiency and Emissions Exploring Advanced Combustion Regimes for Efficiency and Emissions 2003 DEER Conference Presentation: Oak Ridge...

  20. Use of Low Cetane Fuel to Enable Low Temperature Combustion

    Broader source: Energy.gov [DOE]

    Document:  ace011_ciatti_2013_o.pdfTechnology Area: Advanced Combustion; Combustion and Emissions ControlPresenter: Steve CiattiPresenting Organization: Argonne National Laboratory (ANL...

  1. Particulate Produced from Advanced Combustion Operation in a...

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

    Produced from Advanced Combustion Operation in a Compression Ignition Engine Particulate Produced from Advanced Combustion Operation in a Compression Ignition Engine Determine...

  2. Code Gaps and Future Research Needs of Combustion Safety: Building...

    Energy Savers [EERE]

    Code Gaps and Future Research Needs of Combustion Safety: Building America Expert Meeting Update Code Gaps and Future Research Needs of Combustion Safety: Building America Expert...

  3. Computationally Efficient Modeling of High-Efficiency Clean Combustion Engines

    Broader source: Energy.gov [DOE]

    Document:  ace012_flowers_2013_o.pdfTechnology Area: Advanced Combustion; Combustion and Emissions ControlPresenter: Dan FlowersPresenting Organization: Lawrence Livermore National Laboratory (LLNL...

  4. Advanced Diesel Combustion with Low Hydrocarbon and Carbon Monoxide...

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

    Combustion with Low Hydrocarbon and Carbon Monoxide Emissions Advanced Diesel Combustion with Low Hydrocarbon and Carbon Monoxide Emissions Poster presented at the 16th Directions...

  5. CRADA with Cummins on Characterization and Reduction of Combustion...

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

    Cummins on Characterization and Reduction of Combustion Variations CRADA with Cummins on Characterization and Reduction of Combustion Variations 2012 DOE Hydrogen and Fuel Cells...

  6. Evaluation of High Efficiency Clean Combustion (HECC) Strategies...

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

    High Efficiency Clean Combustion (HECC) Strategies for Meeting Future Emissions Regulations in Light-Duty Engines Evaluation of High Efficiency Clean Combustion (HECC) Strategies...

  7. Singular perturbation problem in boundary/fractional combustion

    E-Print Network [OSTI]

    2015-08-18

    reaction-diffusion equation, where the reaction term is of combustion type. ... Free boundary problem, combustion theory, boundary reaction- diffusion, fractional ...

  8. Vehicle Technologies Office: 2010 Advanced Combustion R&D Annual...

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

    10 Advanced Combustion R&D Annual Progress Report Vehicle Technologies Office: 2010 Advanced Combustion R&D Annual Progress Report 2010advcombustionengine.pdf More Documents &...

  9. Modeling of HCCI and PCCI Combustion Processes | Department of...

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

    HCCI and PCCI Combustion Processes Modeling of HCCI and PCCI Combustion Processes 2005 Diesel Engine Emissions Reduction (DEER) Conference Presentations and Posters...

  10. Overview of Sonex Combustion Systems (SCS) for DI Engines | Department...

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

    Sonex Combustion Systems (SCS) for DI Engines Overview of Sonex Combustion Systems (SCS) for DI Engines The SCS system has undergone computational and experimental verification and...

  11. 2.61 Internal Combustion Engines, Spring 2004

    E-Print Network [OSTI]

    Heywood, John B.

    Fundamentals of how the design and operation of internal combustion engines affect their performance, operation, fuel requirements, and environmental impact. Study of fluid flow, thermodynamics, combustion, heat transfer ...

  12. Enabling High Efficiency Low Temperature Combustion by Adaptive...

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

    Low Temperature Combustion by Adaptive In-Situ Jet Cooling Enabling High Efficiency Low Temperature Combustion by Adaptive In-Situ Jet Cooling A new approach, called...

  13. Oxygen-Enriched Combustion for Military Diesel Engine Generators...

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

    Oxygen-Enriched Combustion for Military Diesel Engine Generators Oxygen-Enriched Combustion for Military Diesel Engine Generators Substantial increases in brake power and...

  14. Advanced Post-Combustion CO2 Capture Prepared for the

    E-Print Network [OSTI]

    Advanced Post-Combustion CO2 Capture Prepared for the Clean Air Task Force under a grant from...................................................................................... 3 2. Current Status of Post-Combustion Capture

  15. 3-D Combustion Simulation Strategy Status, Future Potential,...

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

    Combustion Simulation Strategy Status, Future Potential, and Application Issues 3-D Combustion Simulation Strategy Status, Future Potential, and Application Issues 2004 Diesel...

  16. Dilute Clean Diesel Combustion Achieves Low Emissions and High...

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

    Dilute Clean Diesel Combustion Achieves Low Emissions and High Efficiency While Avoiding Control Problems of HCCI Dilute Clean Diesel Combustion Achieves Low Emissions and High...

  17. Advancement in Fuel Spray and Combustion Modeling for Compression...

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

    Advancement in Fuel Spray and Combustion Modeling for Compression Ignition Engine Applications Advancement in Fuel Spray and Combustion Modeling for Compression Ignition Engine...

  18. Numerical Modeling of PCCI Combustion | Department of Energy

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

    PCCI Combustion Numerical Modeling of PCCI Combustion 2004 Diesel Engine Emissions Reduction (DEER) Conference Presentation: Lawrence Livermore National LaboratoryUniversity of...

  19. CFD Combustion Modeling with Conditional Moment Closure using Tabulated Chemistry

    Broader source: Energy.gov [DOE]

    A method is presented that allows for efficient conditional moment closure combustion simulations through the use of a progress variable based parameterization of the combustion chemistry.

  20. CFD Combustion Modeling with Conditional Moment Closure using...

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

    Combustion Modeling with Conditional Moment Closure using Tabulated Chemistry CFD Combustion Modeling with Conditional Moment Closure using Tabulated Chemistry A method is...

  1. Accurate Predictions of Fuel Effects on Combustion and Emissions...

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

    on Combustion and Emissions in Engines Using CFD Simulations With Detailed Fuel Chemistry Accurate Predictions of Fuel Effects on Combustion and Emissions in Engines Using...

  2. Vehicle Technologies Office: 2012 Advanced Combustion R&D Annual...

    Energy Savers [EERE]

    Vehicle Technologies Office: 2012 Advanced Combustion R&D Annual Progress Report Vehicle Technologies Office: 2012 Advanced Combustion R&D Annual Progress Report Annual report on...

  3. Improve Your Boiler's Combustion Efficiency | Department of Energy

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

    Improve Your Boiler's Combustion Efficiency This tip sheet outlines how to improve boiler combustion efficiency as part of an optimized steam system. STEAM TIP SHEET 4 Improve...

  4. Improve Your Boiler's Combustion Efficiency, Energy Tips: STEAM...

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

    4 Improve Your Boiler's Combustion Efficiency Combustion Efficiency Operating your boiler with an optimum amount of excess air will minimize heat loss up the stack and improve...

  5. Modeling Combustion Control for High Power Diesel Mode Switching...

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

    Combustion Control for High Power Diesel Mode Switching Modeling Combustion Control for High Power Diesel Mode Switching Poster presentation given at the 16th Directions in...

  6. Large Eddy Simulation (LES) Applied to Advanced Engine Combustion...

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

    Advanced Engine Combustion Research Large Eddy Simulation (LES) Applied to Advanced Engine Combustion Research 2012 DOE Hydrogen and Fuel Cells Program and Vehicle Technologies...

  7. Factors Affecting HCCI Combustion Phasing for Fuels with Single...

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

    Affecting HCCI Combustion Phasing for Fuels with Single- and Dual-Stage Chemistry Factors Affecting HCCI Combustion Phasing for Fuels with Single- and Dual-Stage Chemistry 2004...

  8. Glow Plug Integrated Piezo-Ceramic Combustion Sensor for Diesel...

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

    Glow Plug Integrated Piezo-Ceramic Combustion Sensor for Diesel Engines Glow Plug Integrated Piezo-Ceramic Combustion Sensor for Diesel Engines 2005 Diesel Engine Emissions...

  9. Guide to Low-Emission Boiler and Combustion Equipment Selection...

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

    Low-Emission Boiler and Combustion Equipment Selection Guide to Low-Emission Boiler and Combustion Equipment Selection The guide provides background information about various types...

  10. Heavy-Duty Engine Combustion Optimization for High Thermal Efficiency...

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

    Combustion Optimization for High Thermal Efficiency Targeting EPA 2010 Emissions Heavy-Duty Engine Combustion Optimization for High Thermal Efficiency Targeting EPA 2010 Emissions...

  11. Enabling Low Temperature Combustion Through Thermo-Chemical Recuperati...

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

    Low Temperature Combustion Through Thermo-Chemical Recuperation Enabling Low Temperature Combustion Through Thermo-Chemical Recuperation Poster presentation from the 2007 Diesel...

  12. Improving Combustion Software to Solve Detailed Chemical Kinetics...

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

    Combustion Software to Solve Detailed Chemical Kinetics for HECC Improving Combustion Software to Solve Detailed Chemical Kinetics for HECC 2012 DOE Hydrogen and Fuel Cells Program...

  13. Low Temperature Combustion with Thermo-chemical Recuperation...

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

    Low Temperature Combustion with Thermo-chemical Recuperation to Maximize In-use Engine Efficiency Low Temperature Combustion with Thermo-chemical Recuperation to Maximize In-use...

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

    Office of Scientific and Technical Information (OSTI)

    Combustion, Control, and Fuel Effects in a Spark Assisted HCCI Engine Equipped with Variable Valve Timing Citation Details In-Document Search Title: Combustion, Control, and Fuel...

  15. Application of advanced hydrocarbon characterization and its consequences on future fuel properties and advanced combustion research

    Office of Energy Efficiency and Renewable Energy (EERE)

    Research on future fuels chemistry and effects on combustion in advanced internal combustion engines

  16. Dry low NOx combustion system with pre-mixed direct-injection secondary fuel nozzle

    DOE Patents [OSTI]

    Zuo, Baifang; Johnson, Thomas; Ziminsky, Willy; Khan, Abdul

    2013-12-17

    A combustion system includes a first combustion chamber and a second combustion chamber. The second combustion chamber is positioned downstream of the first combustion chamber. The combustion system also includes a pre-mixed, direct-injection secondary fuel nozzle. The pre-mixed, direct-injection secondary fuel nozzle extends through the first combustion chamber into the second combustion chamber.

  17. 2003 Laser Diagnostic in Combustion Conference

    SciTech Connect (OSTI)

    Mark G. Allen

    2004-09-10

    The GRC Laser Diagnostics in Combustion aims at bringing together scientists and engineers working in the front edge of research and development to discuss and find new ways to solve problems connected to combustion diagnostics. Laser-based techniques have proven to be very efficient tools for studying combustion processes thanks to features as non-intrusiveness in combination with high spatial and temporal resolution. Major tasks for the community are to develop and apply techniques for quantitative measurements with high precision e.g of species concentrations, temperatures, velocities and particles characteristics (size and concentration). These issues are of global interest, considering that the major part of the World's energy conversion comes from combustion sources and the influence combustion processes have on the environment and society.

  18. Highly turbulent counterflow flames: A laboratory scale benchmark for practical systems

    SciTech Connect (OSTI)

    Coppola, Gianfilippo; Coriton, Bruno; Gomez, Alessandro

    2009-09-15

    We propose a highly turbulent counterflow flame as a very useful benchmark of complexity intermediate between laminar flames and practical systems. By operating in a turbulent Reynolds number regime of relevance to practical systems such as gas turbines and internal combustion engines, it retains the interaction of turbulence and chemistry of such environments, but offers several advantages including: (a) the achievement of high Reynolds numbers without pilot flames, which is particularly advantageous from a modeling standpoint; (b) control of the transition from stable flames to local extinction/reignition conditions; (c) compactness of the domain by comparison with jet flames, with obvious advantages from both a diagnostic and, especially, a computational viewpoint; and (d) the reduction or, altogether, elimination of soot formation, thanks to the high strain rates and low residence times of such a system, and the establishment of conditions of large stoichiometric mixture fraction, as required for robust flame stabilization. We demonstrate the phenomenology of such highly strained turbulent flames under conditions spanning unpremixed, partially premixed and premixed regimes. The system lends itself to the validation of DNS and other computational models. It is also well-suited for the examination of practical fuel blends - a need that is becoming more and more pressing in view of the anticipated diversification of the future fossil fuel supply. (author)

  19. Time-resolved gas temperatures in the oscillating turbulent flow of a pulse combustor tail pipe

    SciTech Connect (OSTI)

    Dec, J.E. (Michigan Univ., Ann Arbor, MI (USA)); Keller, J.O. (Sandia National Labs., Livermore, CA (USA). Combustion Research Faclity)

    1990-06-01

    This paper reports the cyclic behavior of the gas temperature in the oscillating turbulent flow in a pulse combustor tail pipe studied using two-line atomic fluorescence. In this flow, the oscillations result from an acoustic resonance, and have amplitudes of up to 5 times the mean velocity. Oscillation frequencies were varied from 67 to 101 Hz. Spatially resolved temperature measurements were made to within 400 {mu}m of the wall, providing cycle-resolved profiles of the temperature and the random temperature fluctuations. The combustor-cycle phase relationships among the gas temperature, random-temperature-fluctuation intensity, velocity, and combustion chamber pressure, are compared.

  20. Second Law Analysis of Constant Temperature Diesel Combustion

    SciTech Connect (OSTI)

    Druecke, Dr. Ben [University of Wisconsin; Foster, Prof. Dave [University of Wisconsin; Klein, Prof. Sandy [University of Wisconsin; Daw, C Stuart [ORNL; Chakravarthy, Veerathu K [ORNL; Graves, Ronald L [ORNL

    2006-01-01

    The results from a second law analysis of a constant temperature diesel combustion process are presented and show that this process is not significantly more reversible than conventional combustion. In addition to quantifying the total availability destruction in combustion, the magnitudes of the combustion irreversibilities attributable to each irreversible subprocess (mixing, oxidation and internal heat transfer) were determined. The primary contributor to combustion irreversibilities is the thermal interaction of reacting and non-reacting species during the oxidation and internal thermal energy transfer subprocesses. Increasing combustion temperature significantly decreases availability destruction by making the oxidation and internal thermal energy transfer processes more reversible. While increasing combustion temperature decreases combustion irreversibility, it also results in an increase in exhaust temperature. A tradeoff exists between large availability destruction at low combustion temperatures and large amounts of availability discarded in the exhaust at high combustion temperatures. The optimum amount of work was found to occur for a combustion temperature of approximately 1600 K.

  1. Real-time combustion controller

    DOE Patents [OSTI]

    Lindner, J.S.; Shepard, W.S.; Etheridge, J.A.; Jang, P.R.; Gresham, L.L.

    1997-02-04

    A method and system are disclosed for regulating the air to fuel ratio supplied to a burner to maximize the combustion efficiency. Optical means are provided in close proximity to the burner for directing a beam of radiation from hot gases produced by the burner to a plurality of detectors. Detectors are provided for sensing the concentration of, inter alia, CO, CO{sub 2}, and H{sub 2}O. The differences between the ratios of CO to CO{sub 2} and H{sub 2}O to CO are compared with a known control curve based on those ratios for air to fuel ratios ranging from 0.85 to 1.30. The fuel flow is adjusted until the difference between the ratios of CO to CO{sub 2} and H{sub 2}O to CO fall on a desired set point on the control curve. 20 figs.

  2. Pulsed atmospheric fluidized bed combustion

    SciTech Connect (OSTI)

    Not Available

    1992-10-01

    The design of the Pulsed Atmospheric Fluidized Bed Combustor (PAFBC) as described in the Quarterly Report for the period April--June, 1992 was reviewed and minor modifications were included. The most important change made was in the coal/limestone preparation and feed system. Instead of procuring pre-sized coal for testing of the PAFBC, it was decided that the installation of a milling system would permit greater flexibility in the testing with respect to size distributions and combustion characteristics in the pulse combustor and the fluid bed. Particle size separation for pulse combustor and fluid bed will be performed by an air classifier. The modified process flow diagram for the coal/limestone handling system is presented in Figure 1. The modified process flow diagrams of the fluidized bed/steam cycle and ash handling systems are presented in Figures 2 and 3, respectively.

  3. Fluidized-bed combustion fuel

    SciTech Connect (OSTI)

    Rich, J.W. Jr.

    1990-10-09

    This patent describes a process for producing from a solid carbonaceous refuse a high ash fuel for use in a circulating fluidized-bed combustion chamber. It comprises separating from the refuse a carbonaceous portion having an ash content in a selected range percent by weight; separating the carbonaceous portion into first and second fractions, the first fraction being at or above a selected size; crushing the first fraction; and combining the crushed first fraction with the second fraction. Also described is a process wherein the selected ash content range is between about 30 percent and about 50 percent, by weight. Also described is a process wherein the selected size is above about 1/4 inch.

  4. Multiple vane rotary internal combustion engine

    SciTech Connect (OSTI)

    Pangman, E.L.

    1994-01-11

    A three-piece housing enclosing a cavity has rotatably mounted therein a rotor having a plurality of slots, each slot supporting a vane. Each vane has a retention end guided in its revolution around the rotor by an internal, non-circular vane retention track. Two adjacent vanes define opposite sides of a combustion chamber, while the housing and the portion of the rotor between the adjacent vanes form the remaining surfaces of the combustion chamber. Each combustion chamber is rotated past an intake port, a diagonal plasma bleed-over groove, and an exhaust port to accomplish the phases of a combustion cycle. Fuel ignition is provided to more than one combustion chamber at a time by expanding gases passing through a plasma bleed-over groove and being formed into a vortex that ignites and churns the charge in a succeeding combustion chamber. Exhaust gases remaining after primary evacuation are removed by a secondary evacuation system utilizing a venturi creating negative pressure which evacuates the combustion chamber. Lubrication is circulated through the engine without the use of a lubricant pump. The centrifugal force of the rotating rotor causes the lubricant therein to be pressurized thereby drawing additional lubricant into the closed system and forcing lubricant within the engine to be circulated. 9 figs.

  5. Simulation of turbulent explosion of hydrogen-air mixtures

    E-Print Network [OSTI]

    Ahmed, I.; Swaminathan, N.

    2014-04-27

    ]. Also, fundamental understanding of hydrogen combustion is important from safety view points, for example generation and accumulation of hydrogen in nuclear reactors [7] and rupturing of a pressurised hydrogen storage tank can lead to explosions. A... . The leading edge radius, rf , is defined using c˜ = c˜1 = 0.05 iso-level in the simulation and the above radii and ?t are taken from one of the simulations chosen arbitrarily. The theoretical value for the heat release is 4.68 kJ and this value calculated from...

  6. Magnetic field effects on the thermonuclear combustion front of Chandrasekhar mass white dwarfs

    E-Print Network [OSTI]

    Cristian R. Ghezzi; Elisabete M. de Gouveia Dal Pino; Jorge E. Horvath

    2000-12-06

    The explosion of a type Ia supernova starts in a white dwarf as a laminar deflagration at the center of the star and soon several hydrodynamic instabilities, in particular, the Rayleigh-Taylor instability, begin to act. A cellular stationary combustion and a turbulent combustion regime are rapidly achieved by the flame and maintained up to the end of the so-called flamelet regime when the transition to detonation is believed to occur. The burning velocity at these regimes is well described by the fractal model of combustion. Using a semi-analytic approach, we describe the effect of magnetic fields on the fractalization of the front considering a white dwarf with a nearly dipolar magnetic field. We find an intrinsic asymmetry on the velocity field that may be maintained up to the free expansion phase of the remnant. Considering the strongest values inferred for a white dwarf's magnetic fields with strengths up to $10^{8}-10^{9}$ G at the surface and assuming that the field near the centre is roughly 10 times greater, asymmetries in the velocity field higher than $10-20 %$ are produced between the magnetic polar and the equatorial axis of the remnant which may be related to the asymmetries found from recent spectropolarimetric observations of very young SN Ia remnants. Dependence of the asymmetry with white dwarf composition is also analyzed.

  7. Misfire tolerant combustion-powered actuation

    DOE Patents [OSTI]

    Spletzer, Barry L. (Albuquerque, NM); Fischer, Gary J. (Albuquerque, NM); Marron, Lisa C. (Albuquerque, NM); Kuehl, Michael A. (Albuquerque, NM)

    2001-01-01

    The present invention provides a combustion-powered actuator that is suitable for intermittent actuation, that is suitable for use with atmospheric pressure carburetion, and that requires little electrical energy input. The present invention uses energy from expansion of pressurized fuel to effectively purge a combustion chamber, and to achieve atmospheric pressure carburetion. Each purge-fill-power cycle can be independent, allowing the actuator to readily tolerate misfires. The present invention is suitable for use with linear and rotary operation combustion chambers, and is suitable for use in a wide variety of applications.

  8. Chaotic Combustion in Spark Ignition Engines

    E-Print Network [OSTI]

    M. Wendeker; J. Czarnigowski; G. Litak; K. Szabelski

    2002-12-27

    We analyse the combustion process in a spark ignition engine using the experimental data of an internal pressure during the combustion process and show that the system can be driven to chaotic behaviour. Our conclusion is based on the observation of unperiodicity in the time series, suitable stroboscopic maps and a complex structure of a reconstructed strange attractor. This analysis can explain that in some circumstances the level of noise in spark ignition engines increases considerably due to nonlinear dynamics of a combustion process.

  9. Annual Report: Advanced Combustion (30 September 2012)

    SciTech Connect (OSTI)

    Hawk, Jeffrey; Richards, George

    2012-09-30

    The Advanced Combustion Project addresses fundamental issues of fire-side and steam-side corrosion and materials performance in oxy-fuel combustion environments and provides an integrated approach into understanding the environmental and mechanical behavior such that environmental degradation can be ameliorated and long-term microstructural stability, and thus, mechanical performance can lead to longer lasting components and extended power plant life. The technical tasks of this effort are Oxy-combustion Environment Characterization, Alloy Modeling and Life Prediction, and Alloy Manufacturing and Process Development.

  10. Internal combustion engine injection superheated steam

    SciTech Connect (OSTI)

    Mahoney, F.G.

    1991-01-22

    This patent describes a method for introducing water vapor to the combustion chambers of an internal combustion engine. It comprises: introducing a metered amount of liquid water into a heat exchanger; contacting the heat exchanger directly with hot exhaust gases emanating from the exhaust manifold; maintaining the water in the heat exchanger for a period sufficient to vaporize the water into steam and superheat same; reducing pressure and increasing temperature to create superheated steam; introducing the superheated steam into the air supply proximate to the air induction system, upstream of any carburetion, of the internal combustion engine.

  11. Planar Richtmyer-Meshkov instabilities and transition to turbulence

    SciTech Connect (OSTI)

    Grinstein, Fernando F [Los Alamos National Laboratory; Gowardhan, Akshay [Los Alamos National Laboratory; Ristorcelli, Ray [Los Alamos National Laboratory

    2011-01-21

    Extensive recent work has demonstrated that predictive under-resolved simulations of the velocity fields in turbulent flows are possible without resorting to explicit subgrid models. When using a class of physics-capturing high-resolution finite-volume numerical algorithms. This strategy is denoted implicit large eddy simulation (ILES, MILES). The performance of ILES in the substantially more difficult problem of under-resolved material mixing driven by under-resolved velocity fields and initial conditions (ICs) is a focus of the present work. Progress is presented in analyzing the effects of IC combined spectral content and thickness parametrizations. In the large eddy simulation (LES). the large energy containing structures are resolved, the smaller, presumably more isotropic, structures are filtered out, and effects of subgrid scales (SGS) are modeled. ILES effectively addresses the seemingly insurmountable issues posed to LES by under-resolution. by relying on the use of SGS modeling and filtering provided implicitly by a class of physics capturing numerics; extensive verification and validation in areas of engineering. geophysics. and astrophysics has been reported. In many areas of interest such as. inertial confinement fusion. understanding the collapse of the outer cores of supernovas. and supersonic combustion engines, vorticity is introduced at material interfaces by the impulsive loading of shock waves. and turbulence is generated via Richtmyer-Meshkov instabilities (RMI). Given that ILES is based on locally-adaptive, non-oscillatory. finite-volume methods it is naturally suited to emulate shock physics. The unique combination of shock and turbulence emulation capabilities supports direct use of ILES as an effective simulation anzatz for RMI. Here, we further test this approach using a particular strategy based on a nominally-inviscid, Schmidt number {approx} 1, simulation model that uses the LANL RAGE code to investigate planar RMI. Issues of initial material interface characterization and modeling difficulties, and effects of IC resolved spectral content on transitional and late-time turbulent mixing were examined in our previous work. The focus here is to carry out a systematic analysis of effects of combined IC spectral content and thickness.

  12. Turbulent equipartitions in two dimensional drift convection

    SciTech Connect (OSTI)

    Isichenko, M.B.; Yankov, V.V.

    1995-07-25

    Unlike the thermodynamic equipartition of energy in conservative systems, turbulent equipartitions (TEP) describe strongly non-equilibrium systems such as turbulent plasmas. In turbulent systems, energy is no longer a good invariant, but one can utilize the conservation of other quantities, such as adiabatic invariants, frozen-in magnetic flux, entropy, or combination thereof, in order to derive new, turbulent quasi-equilibria. These TEP equilibria assume various forms, but in general they sustain spatially inhomogeneous distributions of the usual thermodynamic quantities such as density or temperature. This mechanism explains the effects of particle and energy pinch in tokamaks. The analysis of the relaxed states caused by turbulent mixing is based on the existence of Lagrangian invariants (quantities constant along fluid-particle or other orbits). A turbulent equipartition corresponds to the spatially uniform distribution of relevant Lagrangian invariants. The existence of such turbulent equilibria is demonstrated in the simple model of two dimensional electrostatically turbulent plasma in an inhomogeneous magnetic field. The turbulence is prescribed, and the turbulent transport is assumed to be much stronger than the classical collisional transport. The simplicity of the model makes it possible to derive the equations describing the relaxation to the TEP state in several limits.

  13. Active control for turbulent premixed flame simulations

    SciTech Connect (OSTI)

    Bell, John B.; Day, Marcus S.; Grcar, Joseph F.; Lijewski, Michael J.

    2004-03-26

    Many turbulent premixed flames of practical interest are statistically stationary. They occur in combustors that have anchoring mechanisms to prevent blow-off and flashback. The stabilization devices often introduce a level of geometric complexity that is prohibitive for detailed computational studies of turbulent flame dynamics. As a result, typical detailed simulations are performed in simplified model configurations such as decaying isotropic turbulence or inflowing turbulence. In these configurations, the turbulence seen by the flame either decays or, in the latter case, increases as the flame accelerates toward the turbulent inflow. This limits the duration of the eddy evolutions experienced by the flame at a given level of turbulent intensity, so that statistically valid observations cannot be made. In this paper, we apply a feedback control to computationally stabilize an otherwise unstable turbulent premixed flame in two dimensions. For the simulations, we specify turbulent in flow conditions and dynamically adjust the integrated fueling rate to control the mean location of the flame in the domain. We outline the numerical procedure, and illustrate the behavior of the control algorithm. We use the simulations to study the propagation and the local chemical variability of turbulent flame chemistry.

  14. Pulse combustion: an assessment of opportunities for increased efficiency

    SciTech Connect (OSTI)

    Brenchley, D.L.; Bomelburg, H.J.

    1984-12-01

    The results of a literature review on pulse combustion are discussed. Current, near-future, and potential opportunities for pulse combustion applications are summarized, and the barriers to developing and using pulse combustion technology are discussed, along with research and development needs. Also provided are the proceedings of a pulse combustion workshop held in May, 1984 in Seattle, Washington. (LEW)

  15. Using Biofuel Tracers to Study Alternative Combustion Regimes

    E-Print Network [OSTI]

    Mack, John Hunter; Flowers, Daniel L.; Buchholz, Bruce A.; Dibble, Robert W.

    2006-01-01

    blending fuels with different properties can yield small changes in combustion timing. Using fuel components

  16. Impact of Variable Valve Timing on Low Temperature Combustion

    Broader source: Energy.gov [DOE]

    Documents effects of variable valve actuation in implementing low temperature combustion in production engine platform.

  17. Using Biofuel Tracers to Study Alternative Combustion Regimes

    E-Print Network [OSTI]

    Mack, John Hunter; Flowers, Daniel L.; Buchholz, Bruce A.; Dibble, Robert W.

    2006-01-01

    Section B (NIMB) Using Biofuel Tracers to Study Alternativeinjection. We investigate biofuel HCCI combustion, and use

  18. Internal combustion engine utilizing stratified charge combustion process

    SciTech Connect (OSTI)

    Artman, N.G.

    1991-07-16

    This patent describes an internal combustion engine in which a piston is reciprocal alternately toward and from the upper end of a cylinder within a variable volume space adjacent to such end, a cylinder head having a face in closing relation with such cylinder end and containing a precombustion chamber with a sidewall having an inner periphery constructed about an axis extending upwardly from the cylinder and the periphery having an open lower end in two-way communication through the face with the variable volume space, the lower open end being smaller in diameter than the diameter of the cylinder, the upper end of the chamber having an air inlet passage closable by a valve, the chamber being operable when the valve is open and attendant to movement of the piston downwardly from the upper cylinder end to receive from the inlet passage a main inlet air stream and conduct the same downwardly therein and discharge the same through the open end downwardly therein and discharge the same through the open end downwardly into the variable volume space.

  19. Predicting combustion properties of hydrocarbon fuel mixtures

    E-Print Network [OSTI]

    Goldsmith, Claude Franklin, III

    2010-01-01

    In this thesis, I applied computational quantum chemistry to improve the accuracy of kinetic mechanisms that are used to model combustion chemistry. I performed transition state theory calculations for several reactions ...

  20. Two phase exhaust for internal combustion engine

    DOE Patents [OSTI]

    Vuk, Carl T. (Denver, IA)

    2011-11-29

    An internal combustion engine having a reciprocating multi cylinder internal combustion engine with multiple valves. At least a pair of exhaust valves are provided and each supply a separate power extraction device. The first exhaust valves connect to a power turbine used to provide additional power to the engine either mechanically or electrically. The flow path from these exhaust valves is smaller in area and volume than a second flow path which is used to deliver products of combustion to a turbocharger turbine. The timing of the exhaust valve events is controlled to produce a higher grade of energy to the power turbine and enhance the ability to extract power from the combustion process.

  1. Oil shale retorting and combustion system

    DOE Patents [OSTI]

    Pitrolo, Augustine A. (Fairmont, WV); Mei, Joseph S. (Morgantown, WV); Shang, Jerry Y. (Fairfax, VA)

    1983-01-01

    The present invention is directed to the extraction of energy values from l shale containing considerable concentrations of calcium carbonate in an efficient manner. The volatiles are separated from the oil shale in a retorting zone of a fluidized bed where the temperature and the concentration of oxygen are maintained at sufficiently low levels so that the volatiles are extracted from the oil shale with minimal combustion of the volatiles and with minimal calcination of the calcium carbonate. These gaseous volatiles and the calcium carbonate flow from the retorting zone into a freeboard combustion zone where the volatiles are burned in the presence of excess air. In this zone the calcination of the calcium carbonate occurs but at the expense of less BTU's than would be required by the calcination reaction in the event both the retorting and combustion steps took place simultaneously. The heat values in the products of combustion are satisfactorily recovered in a suitable heat exchange system.

  2. Preheated Combustion Air; Industrial Technologies Program (ITP...

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

    to improve efficiency and productivity is to preheat the combustion air going to the burners. The source of this heat energy is the exhaust gas stream, which leaves the process...

  3. State of Industrial Fluidized Bed Combustion 

    E-Print Network [OSTI]

    Mesko, J. E.

    1982-01-01

    A new combustion technique has been developed in the last decade that permits the burning of low quality coal, lignite and other fuels, while maintaining stack emissions within State and Federal limits. Low quality fuels can be burned directly...

  4. State of Fluidized Bed Combustion Technology 

    E-Print Network [OSTI]

    Pope, M.

    1979-01-01

    A new combustion technology has been developed in the last decade that permits the burning of low quality coal, lignite and other fuels, while maintaining stack emissions within State and Federal EPA limits. Low quality fuels can be burned...

  5. Combustion characteristics of alternative liquid fuels

    E-Print Network [OSTI]

    Chong, Cheng Tung

    2011-11-08

    atomizer are investigated using a phase Doppler anemometry (PDA) under non-reacting conditions. The droplet size and velocity distribution of biodiesels are compared to conventional fuels. For spray combustion investigations, a generic gas turbine...

  6. Active combustion control : modeling, design and implementation

    E-Print Network [OSTI]

    Park, Sungbae, 1973-

    2004-01-01

    Continuous combustion systems common in propulsion and power generation applications are susceptible to thermoacoustic instability, which occurs under lean burn conditions close to the flammability where most emissions and ...

  7. Fluid Bed Combustion Applied to Industrial Waste 

    E-Print Network [OSTI]

    Mullen, J. F.; Sneyd, R. J.

    1985-01-01

    Because of its unique ability to handle a wide variety of liquids and solids in an energy efficient and environmentally acceptable manner, fluid bed combustion is being increasingly applied to the utilization of waste materials and low grade fuels...

  8. Vortex driven flame dynamics and combustion instability

    E-Print Network [OSTI]

    Altay, Hurrem Murat

    2005-01-01

    Combustion instability in premixed combustors mostly arises due to the coupling between heat release rate dynamics and system acoustics. It is crucial to understand the instability mechanisms to design reliable, high ...

  9. Engine combustion control via fuel reactivity stratification

    DOE Patents [OSTI]

    Reitz, Rolf Deneys; Hanson, Reed M.; Splitter, Derek A.; Kokjohn, Sage L.

    2015-07-14

    A compression ignition engine uses two or more fuel charges having two or more reactivities to control the timing and duration of combustion. In a preferred implementation, a lower-reactivity fuel charge is injected or otherwise introduced into the combustion chamber, preferably sufficiently early that it becomes at least substantially homogeneously dispersed within the chamber before a subsequent injection is made. One or more subsequent injections of higher-reactivity fuel charges are then made, and these preferably distribute the higher-reactivity matter within the lower-reactivity chamber space such that combustion begins in the higher-reactivity regions, and with the lower-reactivity regions following thereafter. By appropriately choosing the reactivities of the charges, their relative amounts, and their timing, combustion can be tailored to achieve optimal power output (and thus fuel efficiency), at controlled temperatures (and thus controlled NOx), and with controlled equivalence ratios (and thus controlled soot).

  10. Flex-flame burner and combustion method

    DOE Patents [OSTI]

    Soupos, Vasilios (Chicago, IL); Zelepouga, Serguei (Hoffman Estates, IL); Rue, David M. (Chicago, IL); Abbasi, Hamid A. (Naperville, IL)

    2010-08-24

    A combustion method and apparatus which produce a hybrid flame for heating metals and metal alloys, which hybrid flame has the characteristic of having an oxidant-lean portion proximate the metal or metal alloy and having an oxidant-rich portion disposed above the oxidant lean portion. This hybrid flame is produced by introducing fuel and primary combustion oxidant into the furnace chamber containing the metal or metal alloy in a substoichiometric ratio to produce a fuel-rich flame and by introducing a secondary combustion oxidant into the furnace chamber above the fuel-rich flame in a manner whereby mixing of the secondary combustion oxidant with the fuel-rich flame is delayed for a portion of the length of the flame.

  11. Advanced Combustion Concepts - Enabling Systems and Solutions...

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

    advanced control concepts and enabling system to manage multi-modemulti-fuel combustion events and achieve an up to 30 percent fuel economy improvement deer11yilmaz.pdf...

  12. Smouldering Combustion Phenomena in Science and Technology 

    E-Print Network [OSTI]

    Rein, Guillermo

    Smouldering is the slow, low-temperature, flameless form of combustion of a condensed fuel. It poses safety and environmental hazards and allows novel technological application but its fundamentals remain mostly unknown ...

  13. Combustion systems for power-MEMS applications

    E-Print Network [OSTI]

    Spadaccini, Christopher M. (Christopher Michael), 1974-

    2004-01-01

    As part of an effort to develop a micro-scale gas turbine engine for power generation and micro-propulsion applications, this thesis presents the design, fabrication, experimental testing, and modeling of the combustion ...

  14. Fuel injector nozzle for internal combustion engine

    SciTech Connect (OSTI)

    Klomp, E.D.; Peters, B.D.

    1990-06-12

    This patent describes a fuel injection nozzle for a combustion chamber of an internal combustion engine. It comprises: a nozzle body with at least one fuel flow opening therethrough for feed fuel to the chamber, a resilient diaphragm normally sealing the opening and having orifice means therein for further atomizing and directing the pulses into the chamber, fastening means for fixing the diaphragm to the body so that diaphragm can deflect by a predetermined amount under low engine load operating conditions so that a wide angle cone of atomized fuel is injected into and generally at one end of the combustion chamber for the stratified charge thereof and deflect by an amount greater than the first amount of deflection under high engine load operating conditions. A narrow spray cone of atomized fuel is injected in a deeper pattern into and throughout the combustion chamber for optimizing the charge thereof and fuel burns under the low and high load engine operating conditions.

  15. Control of NOx by combustion process modifications

    E-Print Network [OSTI]

    Ber?, J. M.

    1981-01-01

    A theoretical and experimental study was carried out to determine lower bounds of NOx emission from staged combustion of a 0.7%N #6 fuel oil. Thermodynamic and chemical kinetic calculations have shown minimum NOx emissions ...

  16. Optimization of Advanced Diesel Engine Combustion Strategies...

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

    7-11, 2010 -- Washington D.C. ace020reitz2010o.pdf More Documents & Publications Optimization of Advanced Diesel Engine Combustion Strategies Optimization of Advanced Diesel...

  17. Engine combustion control via fuel reactivity stratification

    DOE Patents [OSTI]

    Reitz, Rolf Deneys; Hanson, Reed M; Splitter, Derek A; Kokjohn, Sage L

    2013-12-31

    A compression ignition engine uses two or more fuel charges having two or more reactivities to control the timing and duration of combustion. In a preferred implementation, a lower-reactivity fuel charge is injected or otherwise introduced into the combustion chamber, preferably sufficiently early that it becomes at least substantially homogeneously dispersed within the chamber before a subsequent injection is made. One or more subsequent injections of higher-reactivity fuel charges are then made, and these preferably distribute the higher-reactivity matter within the lower-reactivity chamber space such that combustion begins in the higher-reactivity regions, and with the lower-reactivity regions following thereafter. By appropriately choose the reactivities of the charges, their relative amounts, and their timing, combustion can be tailored to achieve optimal power output (and thus fuel efficiency), at controlled temperatures (and thus controlled NOx), and with controlled equivalence ratios (and thus controlled soot).

  18. Combustion, Explosion, and Shock Waves, Vol. 46, No. 3, pp. , 2010 Combustion of Heterogeneous Nanostructural Systems (Review)

    E-Print Network [OSTI]

    Mukasyan, Alexander

    Combustion, Explosion, and Shock Waves, Vol. 46, No. 3, pp. ­, 2010 Combustion of Heterogeneous submitted November 26, 2009. The current status of research in the field of combustion of heterogeneous mechanisms of combustion in such systems and prospects of their further applications are discussed. Key words

  19. Progress in Energy and Combustion Science 34 (2008) 377416 Discrete reaction waves: Gasless combustion of solid powder mixtures

    E-Print Network [OSTI]

    Mukasyan, Alexander

    2008-01-01

    Progress in Energy and Combustion Science 34 (2008) 377­416 Discrete reaction waves: Gasless combustion of solid powder mixtures A.S. Mukasyana,Ã, A.S. Rogachevb a Department of Chemical Abstract This review considers a specific domain in combustion science, so-called discrete combustion waves

  20. Coal Combustion Products Extension Program

    SciTech Connect (OSTI)

    Tarunjit S. Butalia; William E. Wolfe

    2006-01-11

    This final project report presents the activities and accomplishments of the ''Coal Combustion Products Extension Program'' conducted at The Ohio State University from August 1, 2000 to June 30, 2005 to advance the beneficial uses of coal combustion products (CCPs) in highway and construction, mine reclamation, agricultural, and manufacturing sectors. The objective of this technology transfer/research program at The Ohio State University was to promote the increased use of Ohio CCPs (fly ash, FGD material, bottom ash, and boiler slag) in applications that are technically sound, environmentally benign, and commercially competitive. The project objective was accomplished by housing the CCP Extension Program within The Ohio State University College of Engineering with support from the university Extension Service and The Ohio State University Research Foundation. Dr. Tarunjit S. Butalia, an internationally reputed CCP expert and registered professional engineer, was the program coordinator. The program coordinator acted as liaison among CCP stakeholders in the state, produced information sheets, provided expertise in the field to those who desired it, sponsored and co-sponsored seminars, meetings, and speaking at these events, and generally worked to promote knowledge about the productive and proper application of CCPs as useful raw materials. The major accomplishments of the program were: (1) Increase in FGD material utilization rate from 8% in 1997 to more than 20% in 2005, and an increase in overall CCP utilization rate of 21% in 1997 to just under 30% in 2005 for the State of Ohio. (2) Recognition as a ''voice of trust'' among Ohio and national CCP stakeholders (particularly regulatory agencies). (3) Establishment of a national and international reputation, especially for the use of FGD materials and fly ash in construction applications. It is recommended that to increase Ohio's CCP utilization rate from 30% in 2005 to 40% by 2010, the CCP Extension Program be expanded at OSU, with support from state and federal agencies, utilities, trade groups, and the university, to focus on the following four specific areas of promise: (a) Expanding use in proven areas (such as use of fly ash in concrete); (b) Removing or reducing regulatory and perceptual barriers to use (by working in collaboration with regulatory agencies); (c) Developing new or under-used large-volume market applications (such as structural fills); and (d) Placing greater emphasis on FGD byproducts utilization.

  1. Improved detection of atmospheric turbulence with SLODAR

    E-Print Network [OSTI]

    Michael Goodwin; Charles Jenkins; Andrew Lambert

    2007-06-19

    We discuss several improvements in the detection of atmospheric turbulence using SLOpe Detection And Ranging (SLODAR). Frequently, SLODAR observations have shown strong ground-layer turbulence, which is beneficial to adaptive optics. We show that current methods which neglect atmospheric propagation effects can underestimate the strength of high altitude turbulence by up to ~ 30%. We show that mirror and dome seeing turbulence can be a significant fraction of measured ground-layer turbulence, some cases up to ~ 50%. We also demonstrate a novel technique to improve the nominal height resolution, by a factor of 3, called Generalized SLODAR. This can be applied when sampling high-altitude turbulence, where the nominal height resolution is the poorest, or for resolving details in the important ground-layer.

  2. Oxygen Enriched Combustion System Performance Study 

    E-Print Network [OSTI]

    Chen, S. L.; Kwan, Y.; Abele, A. R.; Silver, L. S.; Kobayashi, H.

    1987-01-01

    i ndustri al furnaces, such as gl ass melting furnaces, appear to be the most promising appli cations for oxygen enriched combustion. In these applications, the principal energy savings results from minimizing the fuel energy required to heat... with non-water cooled refractory burner til es. The Oxytherm Burner was developed jointly by Maxon and Corning Glass for application of oxygen/fuel combustion in glass furnaces. This burner is also a non-water cooled refractory design with a specially...

  3. Coal-Fired Fluidized Bed Combustion Cogeneration 

    E-Print Network [OSTI]

    Thunem, C.; Smith, N.

    1985-01-01

    BED COMBUSTION COGENERATION Cabot Thunem, P.E Norm Smith, P.E. Stanley Consultants, Inc. Muscatine, Iowa ABSTRACT The availability of an environmentally accep table multifuel technology, such as fluidized bed combustion, has encouraged many... steam producers/ users to investigate switching from oil or gas to coal. Changes in federal regulations encouraging cogeneration have further enhanced the economic incentives for primary fuel switching. However, this addition of cogeneration...

  4. Internal combustion engine and method for control

    DOE Patents [OSTI]

    Brennan, Daniel G

    2013-05-21

    In one exemplary embodiment of the invention an internal combustion engine includes a piston disposed in a cylinder, a valve configured to control flow of air into the cylinder and an actuator coupled to the valve to control a position of the valve. The internal combustion engine also includes a controller coupled to the actuator, wherein the controller is configured to close the valve when an uncontrolled condition for the internal engine is determined.

  5. Digital image processing of coal stream combustion 

    E-Print Network [OSTI]

    Gopalakrishnan, Chengappalli Periyasamy

    1994-01-01

    DIGITAL IMAGE PROCESSING OF COAL STREAM COMBUSTION A Thesis by CHENGAPPALLI PERIYASAMY GOPALAKRISHNAN Submitted to Texas A k M University in partial fulfillment of the requirements for the degree of MASTER OF SCIENCE Approved as to style... and content by: a yan Annama at (Chair of Committee) en (Member) Norman C. Gris old (Member) George Peterson (Head of Department) May 1994 Major Subject: Mechanical Engineering ABSTRACT Digital Image Processing of Coal Stream Combustion. (May 1994...

  6. Building America Expert Meeting. Combustion Safety

    SciTech Connect (OSTI)

    Brand, Larry

    2013-03-01

    This is an overview of "The Best Approach to Combustion Safety in a Direct Vent World," held June 28, 2012, in San Antonio, TX. The objective of this Expert Meeting was to identify gaps and barriers that need to be addressed by future research, and to develop data-driven technical recommendations for code updates so that a common approach for combustion safety can be adopted by all members of the building energy efficiency and code communities.

  7. Building America Expert Meeting: Combustion Safety

    SciTech Connect (OSTI)

    Brand, L.

    2013-03-01

    This is a meeting overview of 'The Best Approach to Combustion Safety in a Direct Vent World', held June 28, 2012, in San Antonio, Texas. The objective of this Expert Meeting was to identify gaps and barriers that need to be addressed by future research, and to develop data-driven technical recommendations for code updates so that a common approach for combustion safety can be adopted by all members of the building energy efficiency and code communities.

  8. Large eddy simulations of premixed turbulent flame dynamics : combustion modeling, validation and analysis

    E-Print Network [OSTI]

    Kewlani, Gaurav

    2014-01-01

    High efficiency, low emissions and stable operation over a wide range of conditions are some of the key requirements of modem-day combustors. To achieve these objectives, lean premixed flames are generally preferred as ...

  9. A Topological Framework for the Interactive Exploration of Large Scale Turbulent Combustion

    E-Print Network [OSTI]

    , used in the design of new low-emission burners. In such systems, flames burn in a dynamic cellular mode

  10. MESH CONVERGENCE FOR TURBULENT COMBUSTION XIAOXUE GONG, YING XU, VINAY MAHADEO, TULIN KAMAN , JOHAN

    E-Print Network [OSTI]

    New York at Stoney Brook, State University of

    combustor by Gamba et al. We find that the mesh requirements are not feasible for finite rate chemistry models are assessed for simulation of an experimental model combustor developed by Gamga et al. [9], representing scram jet M = 5-8 flight conditions. These simulations are difficult due to the supersonic flow

  11. Understanding Pre-Mixed Turbulent Combustion Peer-Timo Bremer1

    E-Print Network [OSTI]

    Utah, University of

    component of a clean-coal power plant utilizing hydrogen extracted from coal gasification. Lean premixed and Analytics Center for Enabling Technology (VACET) have developed a suite of general purpose data analysis

  12. Turbulent resuspension of small nondeformable particles

    SciTech Connect (OSTI)

    Lazaridis, M.; Drossinos, Y. [European Commission, Ispra (Italy). Joint Research Centre] [European Commission, Ispra (Italy). Joint Research Centre; Georgopoulos, P.G. [Rutgers-the State Univ., Piscataway, NJ (United States). Environmental and Occupational Health Sciences Inst.] [Rutgers-the State Univ., Piscataway, NJ (United States). Environmental and Occupational Health Sciences Inst.; [Univ. of Medicine and Dentistry of New Jersey, Piscataway, NJ (United States)

    1998-08-01

    An energy-balance resuspension model is modified and applied to the resuspension of a monolayer of nondeformable spherical particles. The particle-surface adhesive force is calculated from a microscopic model based on the Lennard-Jones intermolecular potential. Pairwise additivity of intermolecular interactions is assumed and elastic flattening of the particles is neglected. From the resulting particle-surface interaction potential the natural frequency of vibration of a particle on a surface and the depth of the potential well are calculated. The particle resuspension rate is calculated using the results of a previously developed energy-balance model, where the influence of fluid flow on the bound particle motion is recognized. The effect of surface roughness is included by introducing an effective particle radius that results in log-normally distributed adhesive forces. The predictions of the model are compared with experimental results for the resuspension of Al{sub 2}O{sub 3} particles from stainless steel surfaces. Particle resuspension due to turbulent fluid flow is important in the interaction of the atmosphere with various surfaces and in numerous industrial processes. For example, in the nuclear industry, fission-product aerosols released during a postulated severe accident in a Light Water Reactor may deposit and resuspend repeatedly in the vessel circuit and containment.

  13. Wave turbulence buildup in a vibrating plate

    E-Print Network [OSTI]

    Auliel, Maria Ines; Mordant, Nicolas

    2015-01-01

    We report experimental and numerical results on the buildup of the energy spectrum in wave turbulence of a vibrating thin elastic plate. Three steps are observed: first a short linear stage, then the turbulent spectrum is constructed by the propagation of a front in wave number space and finally a long time saturation due to the action of dissipation. The propagation of a front at the second step is compatible with scaling predictions from the Weak Turbulence Theory.

  14. Dust Combustion Safety Issues for Fusion Applications

    SciTech Connect (OSTI)

    L. C. Cadwallader

    2003-05-01

    This report summarizes the results of a safety research task to identify the safety issues and phenomenology of metallic dust fires and explosions that are postulated for fusion experiments. There are a variety of metal dusts that are created by plasma erosion and disruptions within the plasma chamber, as well as normal industrial dusts generated in the more conventional equipment in the balance of plant. For fusion, in-vessel dusts are generally mixtures of several elements; that is, the constituent elements in alloys and the variety of elements used for in-vessel materials. For example, in-vessel dust could be composed of beryllium from a first wall coating, tungsten from a divertor plate, copper from a plasma heating antenna or diagnostic, and perhaps some iron and chromium from the steel vessel wall or titanium and vanadium from the vessel wall. Each of these elements has its own unique combustion characteristics, and mixtures of elements must be evaluated for the mixture’s combustion properties. Issues of particle size, dust temperature, and presence of other combustible materials (i.e., deuterium and tritium) also affect combustion in air. Combustion in other gases has also been investigated to determine if there are safety concerns with “inert” atmospheres, such as nitrogen. Several coolants have also been reviewed to determine if coolant breach into the plasma chamber would enhance the combustion threat; for example, in-vessel steam from a water coolant breach will react with metal dust. The results of this review are presented here.

  15. Investigation on Flame Characteristics and Burner Operability Issues of Oxy-Fuel Combustion

    SciTech Connect (OSTI)

    Choudhuri, Ahsan

    2013-05-30

    Oxy-fuel combustion has been used previously in a wide range of industrial applications. Oxy- combustion is carried out by burning a hydrocarbon fuel with oxygen instead of air. Flames burning in this configuration achieve higher flame temperatures which present opportunities for significant efficiency improvements and direct capture of CO{sub 2} from the exhaust stream. In an effort to better understand and characterize the fundamental flame characteristics of oxy-fuel combustion this research presents the experimental measurements of flame stability of various oxyfuel flames. Effects of H{sub 2} concentration, fuel composition, exhaust gas recirculation ratio, firing inputs, and burner diameters on the flame stability of these fuels are discussed. Effects of exhaust gas recirculation i.e. CO{sub 2} and H{sub 2}O (steam) acting as diluents on burner operability are also presented. The roles of firing input on flame stability are then analyzed. For this study it was observed that many oxy-flames did not stabilize without exhaust gas recirculation due to their higher burning velocities. In addition, the stability regime of all compositions was observed to decrease as the burner diameter increased. A flashback model is also presented, using the critical velocity gradient g{sub F}) values for CH{sub 4}-O{sub 2}-CO{sub 2} flames. The scaling relation (𝐠{sub F} = 𝐜 𝐒{sub 𝐋}{sup 2}/𝛂) for different burner diameters was obtained for various diameter burners. The report shows that results correlated linearly with a scaling value of c =0.0174. The second part of the study focuses on the experimental measurements of the flow field characteristics of premixed CH{sub 4}/21%O{sub 2}/79%N{sub 2} and CH{sub 4}/38%O{sub 2}/72%CO{sub 2} mixtures at constant firing input of 7.5 kW, constant, equivalence ratio of 0.8, constant swirl number of 0.92 and constant Reynolds Numbers. These measurements were taken in a swirl stabilized combustor at atmospheric pressure. The flow field visualization using Particle Imaging Velocimetry (PIV) technique is implemented to make a better understanding of the turbulence characteristics of CH{sub 4}/air and CH{sub 4}/38%O{sub 2}/72%CO{sub 2} combustion. The velocity fluctuations, turbulence intensities and local propagation velocities along the combustion chamber have been determined. The turbulent intensities increase as we move away from the combustor axis. CH{sub 4}-38%O{sub 2}-72%CO{sub 2} flames have low radial velocity and turbulent intensity distributions at different axial distances when compared with CH{sub 4}-Air flames.

  16. Combustion kinetics and reaction pathways

    SciTech Connect (OSTI)

    Klemm, R.B.; Sutherland, J.W. [Brookhaven National Laboratory, Upton, NY (United States)

    1993-12-01

    This project is focused on the fundamental chemistry of combustion. The overall objectives are to determine rate constants for elementary reactions and to elucidate the pathways of multichannel reactions. A multitechnique approach that features three independent experiments provides unique capabilities in performing reliable kinetic measurements over an exceptionally wide range in temperature, 300 to 2500 K. Recent kinetic work has focused on experimental studies and theoretical calculations of the methane dissociation system (CH{sub 4} + Ar {yields} CH{sub 3} + H + Ar and H + CH{sub 4} {yields} CH{sub 3} + H{sub 2}). Additionally, a discharge flow-photoionization mass spectrometer (DF-PIMS) experiment is used to determine branching fractions for multichannel reactions and to measure ionization thresholds of free radicals. Thus, these photoionization experiments generate data that are relevant to both reaction pathways studies (reaction dynamics) and fundamental thermochemical research. Two distinct advantages of performing PIMS with high intensity, tunable vacuum ultraviolet light at the National Synchrotron Light Source are high detection sensitivity and exceptional selectivity in monitoring radical species.

  17. Structure and Combustion of Magnegases

    E-Print Network [OSTI]

    R. M. Santilli; A. K. Aringazin

    2001-12-20

    In this paper, we study the structure and combustion of magnegases$^{TM}$ (Patented and International Patents Pending), new clean fuels developed by one of us (R.M.S.) [1], which are produced as byproducts of recycling nonradioactive liquid feedstock such as antifreeze waste, engine oil waste, town sewage, crude oil, etc., and generally vary with the liquid used for their production. A new technology, called PlasmaArcFlow\\tm, flows the waste through a submerged electric arc between conventional electrodes. The arc decomposes the liquid molecules into their atomic constituents, and forms a plasma in the immediate vicinity of the electrodes at about 10,000$^o$ F. The technology then moves the plasma away from the electrodes, and controls its recombination into environmentally acceptable fuels. The new fuels possess a ew chemical structure first identified by one of us (R.M.S.), which is characterized by clusters of ordinary molecules and atoms under a new bond of electromagnetic nature. These clusters constitute a new chemical species different than the conventional molecules, since they are stable at ordinary conditions while exhibiting no infrared signature (other than those of conventional molecular constituents), thus confirming that the bond is not of valence type. For this reason the new chemical species is called ''Santilli's electromagnecules'' or ''magnecules''.

  18. Rotary valve internal combustion engine

    SciTech Connect (OSTI)

    Bunk, P.H.

    1989-03-28

    A rotary valve internal combustion engine is described, comprising: an engine block; at least one cylinder in the engine block; at least one cylinder having a top end; cylinder head means located adjacent the top end of at least one cylinder, the cylinder head means having a cylindrically shaped cavity therein, the cylindrically shaped cavity being oriented in perpendicular relation to at least one cylinder; a piston sealingly mounted in at least one cylinder for reciprocable movement therein, the reciprocable movement including an intake stroke and an exhaust stroke; engine shaft means rotatably mounted to the engine block; means within the engine block for converting the reciprocable movement of the piston into rotary motion of the engine shaft means; a cylinder port located at the top end of at least one cylinder; a rotary valve rotatably mounted in the cylindrically shaped cavity; means connected with the engine shaft means for rotating the rotary valve in a predetermined synchronization with the reciprocable movement of the piston; aspiration means in the rotary valve for selectively aspirating at least one cylinder during the intake an exhaust strokes; and a spark plug removably mounted within the rotary valve and rotatable therewith.

  19. The Origin of Molecular Cloud Turbulence

    E-Print Network [OSTI]

    Padoan, Paolo; Haugboelle, Troels; Nordlund, Ake

    2015-01-01

    Turbulence is ubiquitous in molecular clouds (MCs), but its origin is still unclear because MCs are usually assumed to live longer than the turbulence dissipation time. It has been shown that interstellar medium (ISM) turbulence is likely driven by SN explosions, but it has never been demonstrated that SN explosions can establish and maintain a turbulent cascade inside MCs consistent with the observations. In this work, we carry out a simulation of SN-driven turbulence in a volume of (250 pc)^3, specifically designed to test if SN driving alone can be responsible for the observed turbulence inside MCs. We find that SN driving establishes velocity scaling consistent with the usual scaling laws of supersonic turbulence. This also means that previous idealized simulations of MC turbulence, driven with a random, large-scale volume force, were correctly adopted as appropriate models for MC turbulence, despite the artificial driving. We also find the same scaling laws extend to the interior of MCs, and their normal...

  20. Turbulent Supersonic Channel Flow: Direct Numerical Simulation and Modeling

    E-Print Network [OSTI]

    Heinz, Stefan

    modeling: the turbulence frequency production mechanism, wall damping effects on turbulence model frequency production mechanisms and wall damping effects may be explained very well on the basis, Chik w = wall viscosity = kinematic viscosity, = T = turbulent kinematic viscosity, Ck d = pressure