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Sample records for brainpower fuels computer

  1. Even More Brain-Powered Science: Teaching and Learning with Discrepant Events. Brain-Powered Science Series

    ERIC Educational Resources Information Center

    O'Brien, Thomas

    2011-01-01

    How can water and a penny demonstrate the power of mathematics and molecular theory? Do spelling and punctuation really matter to the human brain? The third of Thomas O'Brien's books designed for 5-12 grade science teachers, "Even More Brain-Powered Science" uses the questions above and 11 other inquiry-oriented discrepant events--experiments or…

  2. Even More Brain-Powered Science: Teaching and Learning with Discrepant Events. Brain-Powered Science Series

    ERIC Educational Resources Information Center

    O'Brien, Thomas

    2011-01-01

    How can water and a penny demonstrate the power of mathematics and molecular theory? Do spelling and punctuation really matter to the human brain? The third of Thomas O'Brien's books designed for 5-12 grade science teachers, "Even More Brain-Powered Science" uses the questions above and 11 other inquiry-oriented discrepant events--experiments or…

  3. Computational Design of Advanced Nuclear Fuels

    SciTech Connect

    Savrasov, Sergey; Kotliar, Gabriel; Haule, Kristjan

    2014-06-03

    The objective of the project was to develop a method for theoretical understanding of nuclear fuel materials whose physical and thermophysical properties can be predicted from first principles using a novel dynamical mean field method for electronic structure calculations. We concentrated our study on uranium, plutonium, their oxides, nitrides, carbides, as well as some rare earth materials whose 4f eletrons provide a simplified framework for understanding complex behavior of the f electrons. We addressed the issues connected to the electronic structure, lattice instabilities, phonon and magnon dynamics as well as thermal conductivity. This allowed us to evaluate characteristics of advanced nuclear fuel systems using computer based simulations and avoid costly experiments.

  4. 14 CFR 121.647 - Factors for computing fuel required.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... 14 Aeronautics and Space 3 2010-01-01 2010-01-01 false Factors for computing fuel required. 121.647 Section 121.647 Aeronautics and Space FEDERAL AVIATION ADMINISTRATION, DEPARTMENT OF... § 121.647 Factors for computing fuel required. Each person computing fuel required for the purposes...

  5. Computational modeling of solid oxide fuel cell

    NASA Astrophysics Data System (ADS)

    Penmetsa, Satish Kumar

    In the ongoing search for alternative and environmentally friendly power generation facilities, the solid oxide fuel cell (SOFC) is considered one of the prime candidates for the next generation of energy conversion devices due to its capability to provide environmentally friendly and highly efficient power generation. Moreover, SOFCs are less sensitive to composition of fuel as compared to other types of fuel cells, and internal reforming of the hydrocarbon fuel cell can be performed because of higher operating temperature range of 700°C--1000°C. This allows us to use different types of hydrocarbon fuels in SOFCs. The objective of this study is to develop a three-dimensional computational model for the simulation of a solid oxide fuel cell unit to analyze the complex internal transport mechanisms and sensitivity of the cell with different operating conditions, and also to develop SOFC with higher operating current density with a more uniform gas distributions in the electrodes and with lower ohmic losses. This model includes mass transfer processes due to convection and diffusion in the gas flow channels based on the Navier-Stokes equations as well as combined diffusion and advection in electrodes using Brinkman's hydrodynamic equation and associated electrochemical reactions in the trilayer of the SOFC. Gas transport characteristics in terms of three-dimensional spatial distributions of reactant gases and their effects on electrochemical reactions at the electrode-electrolyte interface, and in the resulting polarizations, are evaluated for varying pressure conditions. Results show the significance of the Brinkman's hydrodynamic model in electrodes to achieve more uniform gas concentration distributions while using a higher operating pressure and over a higher range of operating current densities.

  6. 10 CFR Appendix II to Part 504 - Fuel Price Computation

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... 10 Energy 4 2013-01-01 2013-01-01 false Fuel Price Computation II Appendix II to Part 504 Energy DEPARTMENT OF ENERGY (CONTINUED) ALTERNATE FUELS EXISTING POWERPLANTS Pt. 504, App. II Appendix II to Part... effects of future real price increases for each fuel. The delivered price of an alternate fuel used to...

  7. 10 CFR Appendix II to Part 504 - Fuel Price Computation

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... 10 Energy 4 2011-01-01 2011-01-01 false Fuel Price Computation II Appendix II to Part 504 Energy DEPARTMENT OF ENERGY (CONTINUED) ALTERNATE FUELS EXISTING POWERPLANTS Pt. 504, App. II Appendix II to Part... effects of future real price increases for each fuel. The delivered price of an alternate fuel used to...

  8. 10 CFR Appendix II to Part 504 - Fuel Price Computation

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... 10 Energy 4 2014-01-01 2014-01-01 false Fuel Price Computation II Appendix II to Part 504 Energy DEPARTMENT OF ENERGY (CONTINUED) ALTERNATE FUELS EXISTING POWERPLANTS Pt. 504, App. II Appendix II to Part... effects of future real price increases for each fuel. The delivered price of an alternate fuel used to...

  9. 10 CFR Appendix II to Part 504 - Fuel Price Computation

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... 10 Energy 4 2012-01-01 2012-01-01 false Fuel Price Computation II Appendix II to Part 504 Energy DEPARTMENT OF ENERGY (CONTINUED) ALTERNATE FUELS EXISTING POWERPLANTS Pt. 504, App. II Appendix II to Part 504—Fuel Price Computation (a) Introduction. This appendix provides the equations and...

  10. The Relieving Effects of BrainPower Advanced, a Dietary Supplement, in Older Adults with Subjective Memory Complaints: A Randomized, Double-Blind, Placebo-Controlled Trial

    PubMed Central

    Zhu, Jingfen; Shi, Rong; Chen, Su; Dai, Lihua; Shen, Tian; Feng, Yi; Gu, Pingping; Shariff, Mina; Nguyen, Tuong; Ye, Yeats; Rao, Jianyu; Xing, Guoqiang

    2016-01-01

    Subjective memory complaints (SMCs) are common in older adults that can often predict further cognitive impairment. No proven effective agents are available for SMCs. The effect of BrainPower Advanced, a dietary supplement consisting of herbal extracts, nutrients, and vitamins, was evaluated in 98 volunteers with SMCs, averaging 67 years of age (47–88), in a randomized, double-blind, placebo-controlled trial. Subjective hypomnesis/memory loss (SML) and attention/concentration deficits (SAD) were evaluated before and after 12-week supplementation of BrainPower Advanced capsules (n = 47) or placebo (n = 51), using a 5-point memory questionnaire (1 = no/slight, 5 = severe). Objective memory function was evaluated using 3 subtests of visual/audio memory, abstraction, and memory recall that gave a combined total score. The BrainPower Advanced group had more cases of severe SML (severity ⩾ 3) (44/47) and severe SAD (43/47) than the placebo group (39/51 and 37/51, < 0.05, < 0.05, resp.) before the treatment. BrainPower Advanced intervention, however, improved a greater proportion of the severe SML (29.5%)(13/44) (P < 0.01) and SAD (34.9%)(15/43)(P < 0.01) than placebo (5.1% (2/39) and 13.5% (5/37), resp.). Thus, 3-month BrainPower Advanced supplementation appears to be beneficial to older adults with SMCs. PMID:27190539

  11. The Relieving Effects of BrainPower Advanced, a Dietary Supplement, in Older Adults with Subjective Memory Complaints: A Randomized, Double-Blind, Placebo-Controlled Trial.

    PubMed

    Zhu, Jingfen; Shi, Rong; Chen, Su; Dai, Lihua; Shen, Tian; Feng, Yi; Gu, Pingping; Shariff, Mina; Nguyen, Tuong; Ye, Yeats; Rao, Jianyu; Xing, Guoqiang

    2016-01-01

    Subjective memory complaints (SMCs) are common in older adults that can often predict further cognitive impairment. No proven effective agents are available for SMCs. The effect of BrainPower Advanced, a dietary supplement consisting of herbal extracts, nutrients, and vitamins, was evaluated in 98 volunteers with SMCs, averaging 67 years of age (47-88), in a randomized, double-blind, placebo-controlled trial. Subjective hypomnesis/memory loss (SML) and attention/concentration deficits (SAD) were evaluated before and after 12-week supplementation of BrainPower Advanced capsules (n = 47) or placebo (n = 51), using a 5-point memory questionnaire (1 = no/slight, 5 = severe). Objective memory function was evaluated using 3 subtests of visual/audio memory, abstraction, and memory recall that gave a combined total score. The BrainPower Advanced group had more cases of severe SML (severity ⩾ 3) (44/47) and severe SAD (43/47) than the placebo group (39/51 and 37/51, < 0.05, < 0.05, resp.) before the treatment. BrainPower Advanced intervention, however, improved a greater proportion of the severe SML (29.5%)(13/44) (P < 0.01) and SAD (34.9%)(15/43)(P < 0.01) than placebo (5.1% (2/39) and 13.5% (5/37), resp.). Thus, 3-month BrainPower Advanced supplementation appears to be beneficial to older adults with SMCs.

  12. Computational simulation of liquid fuel rocket injectors

    NASA Technical Reports Server (NTRS)

    Landrum, D. Brian

    1994-01-01

    A major component of any liquid propellant rocket is the propellant injection system. Issues of interest include the degree of liquid vaporization and its impact on the combustion process, the pressure and temperature fields in the combustion chamber, and the cooling of the injector face and chamber walls. The Finite Difference Navier-Stokes (FDNS) code is a primary computational tool used in the MSFC Computational Fluid Dynamics Branch. The branch has dedicated a significant amount of resources to development of this code for prediction of both liquid and solid fuel rocket performance. The FDNS code is currently being upgraded to include the capability to model liquid/gas multi-phase flows for fuel injection simulation. An important aspect of this effort is benchmarking the code capabilities to predict existing experimental injection data. The objective of this MSFC/ASEE Summer Faculty Fellowship term was to evaluate the capabilities of the modified FDNS code to predict flow fields with liquid injection. Comparisons were made between code predictions and existing experimental data. A significant portion of the effort included a search for appropriate validation data. Also, code simulation deficiencies were identified.

  13. 18 CFR 281.304 - Computation of alternative fuel volume.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... alternative fuel volume. 281.304 Section 281.304 Conservation of Power and Water Resources FEDERAL ENERGY... RELATED AUTHORITIES NATURAL GAS CURTAILMENT UNDER THE NATURAL GAS POLICY ACT OF 1978 Alternative Fuel Determination § 281.304 Computation of alternative fuel volume. (a) General rule. For purposes of §...

  14. 18 CFR 281.304 - Computation of alternative fuel volume.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... alternative fuel volume. 281.304 Section 281.304 Conservation of Power and Water Resources FEDERAL ENERGY... RELATED AUTHORITIES NATURAL GAS CURTAILMENT UNDER THE NATURAL GAS POLICY ACT OF 1978 Alternative Fuel Determination § 281.304 Computation of alternative fuel volume. (a) General rule. For purposes of §...

  15. 18 CFR 281.304 - Computation of alternative fuel volume.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... alternative fuel volume. 281.304 Section 281.304 Conservation of Power and Water Resources FEDERAL ENERGY... RELATED AUTHORITIES NATURAL GAS CURTAILMENT UNDER THE NATURAL GAS POLICY ACT OF 1978 Alternative Fuel Determination § 281.304 Computation of alternative fuel volume. (a) General rule. For purposes of §...

  16. 18 CFR 281.304 - Computation of alternative fuel volume.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... alternative fuel volume. 281.304 Section 281.304 Conservation of Power and Water Resources FEDERAL ENERGY... RELATED AUTHORITIES NATURAL GAS CURTAILMENT UNDER THE NATURAL GAS POLICY ACT OF 1978 Alternative Fuel Determination § 281.304 Computation of alternative fuel volume. (a) General rule. For purposes of §...

  17. 18 CFR 281.304 - Computation of alternative fuel volume.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... alternative fuel volume. 281.304 Section 281.304 Conservation of Power and Water Resources FEDERAL ENERGY... RELATED AUTHORITIES NATURAL GAS CURTAILMENT UNDER THE NATURAL GAS POLICY ACT OF 1978 Alternative Fuel Determination § 281.304 Computation of alternative fuel volume. (a) General rule. For purposes of §...

  18. How to harvest brainpower for a brighter future on Earth - bypassing stereotypes in practice

    NASA Astrophysics Data System (ADS)

    Hammarlund, Emma U.

    2016-04-01

    Our ability to detect and respond to patterns, the core asset in scientific work, likely has been a strong evolutionary advantage when navigating between need and danger. We therefore argue that our use of stereotypes for the most part is decoupled from malice but instead profoundly rooted, pervasive and often unchallenged in our daily thought process. The fundamental need for patterns also means that we all express biases - regardless of our gender - such as during teaching, mentoring or collaborations. As culprits, our implicit bias both disfavor (e.g. female or immigrant students) and favor (e.g. the-celebrated-worker's-results-are-probably-stronger-than-they-seem) our fellow workers in unsolicited ways. Additionally, people in our environment adapt to the expectations we express, called the stereotype threat. Ultimately, these two effects likely lead to missed opportunities for new questions and achievements. The omni-present implicit bias also means that some equality efforts, such as quotas, would soon be neutralized unless we train in catching our use of stereotypes in action. We will share our experiences from gender sensitivity training during teaching and assessment, such as the use of anonymous exams, simple 'traps' to demonstrate gender bias, and group work management. We also present views collected in our group on how academic talent management may improve through mentorship, career coaching and general policy decisions. All with the selfish ambition to improve future harvests of brainpower, for science and for sustainable human life on Earth.

  19. FTFc52 - freight train fuel consumption computer program. Software

    SciTech Connect

    Koper, J.; Muhlenberg, J.D.

    1980-09-01

    This tape contains a copy of a computer program for the prediction of fuel consumption of a freight train operated over track with known characteristics. The program is written in FORTRAN for the IBM VM/370 computer.

  20. Computational design and optimization of fuel cells and fuel cell systems: A review

    NASA Astrophysics Data System (ADS)

    Secanell, M.; Wishart, J.; Dobson, P.

    The design of fuel cells is a challenging endeavour due to the multitude of physical phenomena that need to be simultaneously optimized in order to achieve proper fuel cell operation. Fuel cell design is a multi-objective, multi-variable problem. In order to design fuel cells by computational design, a mathematical formulation of the design problem needs to be developed. The problem can then be solved using numerical optimization algorithms and a computational fuel cell model. In the past decade, the fuel cell community has gained momentum in the area of numerical design. In this article, research aimed at using numerical optimization to design fuel cells and fuel cell systems is reviewed. The review discusses the strengths, limitations, advantages, and disadvantages of optimization formulations and numerical optimization algorithms, and insight obtained from previous studies.

  1. Spent fuel management fee methodology and computer code user's manual.

    SciTech Connect

    Engel, R.L.; White, M.K.

    1982-01-01

    The methodology and computer model described here were developed to analyze the cash flows for the federal government taking title to and managing spent nuclear fuel. The methodology has been used by the US Department of Energy (DOE) to estimate the spent fuel disposal fee that will provide full cost recovery. Although the methodology was designed to analyze interim storage followed by spent fuel disposal, it could be used to calculate a fee for reprocessing spent fuel and disposing of the waste. The methodology consists of two phases. The first phase estimates government expenditures for spent fuel management. The second phase determines the fees that will result in revenues such that the government attains full cost recovery assuming various revenue collection philosophies. These two phases are discussed in detail in subsequent sections of this report. Each of the two phases constitute a computer module, called SPADE (SPent fuel Analysis and Disposal Economics) and FEAN (FEe ANalysis), respectively.

  2. A Computer Model for Direct Carbonate Fuel Cells

    SciTech Connect

    Ding, J.; Patel, P.S.; Farooque, M.; Maru, H.C.

    1997-04-01

    A 3-D computer model, describing fluid flow, heat and mass transfer, and chemical and electrochemical reaction processes, has been developed for guiding the direct carbonate fuel cell (DFC) stack design. This model is able to analyze the direct internal reforming (DIR) as well as the integrated IIR (indirect internal reforming)-DIR designs. Reasonable agreements between computed and fuel cell tested results, such as flow variations, temperature distributions, cell potentials, and exhaust gas compositions as well as methane conversions, were obtained. Details of the model and comparisons of the modeling results with experimental DFC stack data are presented in the paper.

  3. Computational fluid dynamics capability for the solid fuel ramjet projectile

    NASA Astrophysics Data System (ADS)

    Nusca, Michael J.; Chakravarthy, Sukumar R.; Goldberg, Uriel C.

    1988-12-01

    A computational fluid dynamics solution of the Navier-Stokes equations has been applied to the internal and external flow of inert solid-fuel ramjet projectiles. Computational modeling reveals internal flowfield details not attainable by flight or wind tunnel measurements, thus contributing to the current investigation into the flight performance of solid-fuel ramjet projectiles. The present code employs numerical algorithms termed total variational diminishing (TVD). Computational solutions indicate the importance of several special features of the code including the zonal grid framework, the TVD scheme, and a recently developed backflow turbulence model. The solutions are compared with results of internal surface pressure measurements. As demonstrated by these comparisons, the use of a backflow turbulence model distinguishes between satisfactory and poor flowfield predictions.

  4. Method for computing the maximum water temperature in a fuel pool containing spent nuclear fuel

    SciTech Connect

    Singh, K.P.; Soler, A.I.; Gupta, J.P.

    1986-01-01

    A method is proposed for computing the upper bound on the local water temperature rise with respect to the bulk temperature in a spent fuel pool. The solution involves casting the continuity and momentum relationships in integral form in terms of the unknown velocity functions. The method of collocation is used to solve the problem. Computer application of this method shows it to be an efficient and cost-effective design tool.

  5. Computational analysis of the SSME fuel preburner flow

    NASA Technical Reports Server (NTRS)

    Wang, T. S.; Farmer, R. C.

    1986-01-01

    A computational fluid dynamics model which simulates the steady state operation of the SSME fuel preburner is developed. Specifically, the model will be used to quantify the flow factors which cause local hot spots in the fuel preburner in order to recommend experiments whereby the control of undesirable flow features can be demonstrated. The results of a two year effort to model the preburner are presented. In this effort, investigating the fuel preburner flowfield, the appropriate transport equations were numerically solved for both an axisymmetric and a three-dimensional configuration. Continuum's VAST (Variational Solution of the Transport equations) code, in conjunction with the CM-1000 Engineering Analysis Workstation and the NASA/Ames CYBER 205, was used to perform the required calculations. It is concluded that the preburner operational anomalies are not due to steady state phenomena and must, therefore, be related to transient operational procedures.

  6. Mathematical and Computational Modeling of Polymer Exchange Membrane Fuel Cells

    NASA Astrophysics Data System (ADS)

    Ulusoy, Sehribani

    In this thesis a comprehensive review of fuel cell modeling has been given and based on the review, a general mathematical fuel cell model has been developed in order to understand the physical phenomena governing the fuel cell behavior and in order to contribute to the efforts investigating the optimum performance at different operating conditions as well as with different physical parameters. The steady state, isothermal model presented here accounts for the combined effects of mass and species transfer, momentum conservation, electrical current distribution through the gas channels, the electrodes and the membrane, and the electrochemical kinetics of the reactions in the anode and cathode catalyst layers. One of the important features of the model is that it proposes a simpler modified pseudo-homogeneous/agglomerate catalyst layer model which takes the advantage of the simplicity of pseudo-homogenous modeling while taking into account the effects of the agglomerates in the catalyst layer by using experimental geometric parameters published. The computation of the general mathematical model can be accomplished in 3D, 2D and 1D with the proper assumptions. Mainly, there are two computational domains considered in this thesis. The first modeling domain is a 2D Membrane Electrode Assembly (MEA) model including the modified agglomerate/pseudo-homogeneous catalyst layer modeling with consistent treatment of water transport in the MEA while the second domain presents a 3D model with different flow filed designs: straight, stepped and tapered. COMSOL Multiphysics along with Batteries and Fuel Cell Module have been used for 2D & 3D model computations while ANSYS FLUENT PEMFC Module has been used for only 3D two-phase computation. Both models have been validated with experimental data. With 2D MEA model, the effects of temperature and water content of the membrane as well as the equivalent weight of the membrane on the performance have been addressed. 3D COMSOL simulation

  7. Recovery Act: Advanced Direct Methanol Fuel Cell for Mobile Computing

    SciTech Connect

    Fletcher, James H.; Cox, Philip; Harrington, William J; Campbell, Joseph L

    2013-09-03

    ABSTRACT Project Title: Recovery Act: Advanced Direct Methanol Fuel Cell for Mobile Computing PROJECT OBJECTIVE The objective of the project was to advance portable fuel cell system technology towards the commercial targets of power density, energy density and lifetime. These targets were laid out in the DOE’s R&D roadmap to develop an advanced direct methanol fuel cell power supply that meets commercial entry requirements. Such a power supply will enable mobile computers to operate non-stop, unplugged from the wall power outlet, by using the high energy density of methanol fuel contained in a replaceable fuel cartridge. Specifically this project focused on balance-of-plant component integration and miniaturization, as well as extensive component, subassembly and integrated system durability and validation testing. This design has resulted in a pre-production power supply design and a prototype that meet the rigorous demands of consumer electronic applications. PROJECT TASKS The proposed work plan was designed to meet the project objectives, which corresponded directly with the objectives outlined in the Funding Opportunity Announcement: To engineer the fuel cell balance-of-plant and packaging to meet the needs of consumer electronic systems, specifically at power levels required for mobile computing. UNF used existing balance-of-plant component technologies developed under its current US Army CERDEC project, as well as a previous DOE project completed by PolyFuel, to further refine them to both miniaturize and integrate their functionality to increase the system power density and energy density. Benefits of UNF’s novel passive water recycling MEA (membrane electrode assembly) and the simplified system architecture it enabled formed the foundation of the design approach. The package design was hardened to address orientation independence, shock, vibration, and environmental requirements. Fuel cartridge and fuel subsystems were improved to ensure effective fuel

  8. GERMINAL — A computer code for predicting fuel pin behaviour

    NASA Astrophysics Data System (ADS)

    Melis, J. C.; Roche, L.; Piron, J. P.; Truffert, J.

    1992-06-01

    In the frame of the R and D on FBR fuels, CEA/DEC is developing the computer code GERMINAL to study the fuel pin thermal-mechanical behaviour during steady-state and incidental conditions. The development of GERMINAL is foreseen in two steps: (1) The GERMINAL 1 code designed as a "working horse" for immediate applications. The version 1 of GERMINAL 1 is presently delivered fully documented with a physical qualification guaranteed up to 8 at%. (2) The version 2 of GERMINAL 1, in addition to what is presently treated in GERMINAL 1 includes the treatment of high burnup effects on the fission gas release and the fuel-clad joint. This version, GERMINAL 1.2, is presently under testing and will be completed up to the end of 1991. The GERMINAL 2 code designed as a reference code for future applications will cover all the aspects of GERMINAL 1 (including high burnup effects) with a more general mechanical treatment, and a completely revised and advanced informatical structure.

  9. Study of operational parameters impacting helicopter fuel consumption. [using computer techniques (computer programs)

    NASA Technical Reports Server (NTRS)

    Cross, J. L.; Stevens, D. D.

    1976-01-01

    A computerized study of operational parameters affecting helicopter fuel consumption was conducted as an integral part of the NASA Civil Helicopter Technology Program. The study utilized the Helicopter Sizing and Performance Computer Program (HESCOMP) developed by the Boeing-Vertol Company and NASA Ames Research Center. An introduction to HESCOMP is incorporated in this report. The results presented were calculated using the NASA CH-53 civil helicopter research aircraft specifications. Plots from which optimum flight conditions for minimum fuel use that can be obtained are presented for this aircraft. The results of the study are considered to be generally indicative of trends for all helicopters.

  10. Computational Analysis of Dynamic SPK(S8)-JP8 Fueled Combustor-Sector Performance

    NASA Technical Reports Server (NTRS)

    Ryder, R.; Hendricks, Roberts C.; Huber, M. L.; Shouse, D. T.

    2010-01-01

    Civil and military flight tests using blends of synthetic and biomass fueling with jet fuel up to 50:50 are currently considered as "drop-in" fuels. They are fully compatible with aircraft performance, emissions and fueling systems, yet the design and operations of such fueling systems and combustors must be capable of running fuels from a range of feedstock sources. This paper provides Smart Combustor or Fuel Flexible Combustor designers with computational tools, preliminary performance, emissions and particulates combustor sector data. The baseline fuel is kerosene-JP-8+100 (military) or Jet A (civil). Results for synthetic paraffinic kerosene (SPK) fuel blends show little change with respect to baseline performance, yet do show lower emissions. The evolution of a validated combustor design procedure is fundamental to the development of dynamic fueling of combustor systems for gas turbine engines that comply with multiple feedstock sources satisfying both new and legacy systems.

  11. A computational model for biofilm-based microbial fuel cells.

    PubMed

    Picioreanu, Cristian; Head, Ian M; Katuri, Krishna P; van Loosdrecht, Mark C M; Scott, Keith

    2007-07-01

    This study describes and evaluates a computational model for microbial fuel cells (MFCs) based on redox mediators with several populations of suspended and attached biofilm microorganisms, and multiple dissolved chemical species. A number of biological, chemical and electrochemical reactions can occur in the bulk liquid, in the biofilm and at the electrode surface. The evolution in time of important MFC parameters (current, charge, voltage and power production, consumption of substrates, suspended and attached biomass growth) has been simulated under several operational conditions. Model calculations evaluated the effect of different substrate utilization yields, standard potential of the redox mediator, ratio of suspended to biofilm cells, initial substrate and mediator concentrations, mediator diffusivity, mass transfer boundary layer, external load resistance, endogenous metabolism, repeated substrate additions and competition between different microbial groups in the biofilm. Two- and three-dimensional model simulations revealed the heterogeneous current distribution over the planar anode surface for younger and patchy biofilms, but becoming uniform in older and more homogeneous biofilms. For uniformly flat biofilms one-dimensional models should give sufficiently accurate descriptions of produced currents. Voltage- and power-current characteristics can also be calculated at different moments in time to evaluate the limiting regime in which the MFC operates. Finally, the model predictions are tested with previously reported experimental data obtained in a batch MFC with a Geobacter biofilm fed with acetate. The potential of the general modeling framework presented here is in the understanding and design of more complex cases of wastewater-fed microbial fuel cells.

  12. Phosphoric acid fuel cell power plant system performance model and computer program

    NASA Technical Reports Server (NTRS)

    Alkasab, K. A.; Lu, C. Y.

    1984-01-01

    A FORTRAN computer program was developed for analyzing the performance of phosphoric acid fuel cell power plant systems. Energy mass and electrochemical analysis in the reformer, the shaft converters, the heat exchangers, and the fuel cell stack were combined to develop a mathematical model for the power plant for both atmospheric and pressurized conditions, and for several commercial fuels.

  13. Computational modeling of a direct propane fuel cell

    NASA Astrophysics Data System (ADS)

    Khakdaman, H.; Bourgault, Y.; Ternan, M.

    2011-03-01

    The first two dimensional mathematical model of a complete direct propane fuel cell (DPFC) is described. The governing equations were solved using FreeFem software that uses finite element methods. Robin boundary conditions were used to couple the anode, membrane, and cathode sub-domains successfully. The model showed that a polytetrafluoroethylene membrane having its pores filled with zirconium phosphate (ZrP-PTFE), in a DPFC at 150 °C performed much the same as other electrolytes; Nafion, aqueous H3PO4, and H2SO4 doped polybenzimidazole, when they were used in DPFCs. One advantage of a ZrP-PTFE at 150 °C is that it operates without liquid phase water. As a result corrosion will be much less severe and it may be possible for non-precious metal catalysts to be used. Computational results showed that the thickness of the catalyst layer could be increased sufficiently so that the pressure drop between the reactant and product channels of the interdigitated flow fields is small. By increasing the width of the land and therefore the reactant's contact time with the catalyst it was possible to approach 100% propane conversion. Therefore fuel cell operation with a minimum concentration of propane in the product stream should be possible. Finally computations of the electrical potential in the ZrP phase, the electron flux in the Pt/C phase, and the overpotential in both the anode and cathode catalyst layers showed that serious errors in the model occurred because proton diffusion, caused by the proton concentration gradient, was neglected in the equation for the conservation of protons.

  14. MEASUREMENTS AND COMPUTATIONS OF FUEL DROPLET TRANSPORT IN TURBULENT FLOWS

    SciTech Connect

    Joseph Katz and Omar Knio

    2007-01-10

    The objective of this project is to study the dynamics of fuel droplets in turbulent water flows. The results are essential for development of models capable of predicting the dispersion of slightly light/heavy droplets in isotropic turbulence. Since we presently do not have any experimental data on turbulent diffusion of droplets, existing mixing models have no physical foundations. Such fundamental knowledge is essential for understanding/modeling the environmental problems associated with water-fuel mixing, and/or industrial processes involving mixing of immiscible fluids. The project has had experimental and numerical components: 1. The experimental part of the project has had two components. The first involves measurements of the lift and drag forces acting on a droplet being entrained by a vortex. The experiments and data analysis associated with this phase are still in progress, and the facility, constructed specifically for this project is described in Section 3. In the second and main part, measurements of fuel droplet dispersion rates have been performed in a special facility with controlled isotropic turbulence. As discussed in detail in Section 2, quantifying and modeling the of droplet dispersion rate requires measurements of their three dimensional trajectories in turbulent flows. To obtain the required data, we have introduced a new technique - high-speed, digital Holographic Particle Image Velocimetry (HPIV). The technique, experimental setup and results are presented in Section 2. Further information is available in Gopalan et al. (2005, 2006). 2. The objectives of the numerical part are: (1) to develop a computational code that combines DNS of isotropic turbulence with Lagrangian tracking of particles based on integration of a dynamical equation of motion that accounts for pressure, added mass, lift and drag forces, (2) to perform extensive computations of both buoyant (bubbles) and slightly buoyant (droplets) particles in turbulence conditions

  15. Computational fluid dynamic simulations of chemical looping fuel reactors utilizing gaseous fuels

    SciTech Connect

    Mahalatkar, Kartikeya; Kuhlman, John; Huckaby, E. David; O'Brien, Thomas

    2011-02-01

    A computational fluid dynamic (CFD) model for the fuel reactor of chemical looping combustion technology has been developed, with special focus on accurately representing the heterogeneous chemical reactions. A continuum two-fluid model was used to describe both the gas and solid phases. Detailed sub-models to account for fluid–particle and particle–particle interaction forces were also incorporated. Two experimental cases were analyzed in this study (Son and Kim, 2006; Mattison et al., 2001). Simulations were carried out to test the capability of the CFD model to capture changes in outlet gas concentrations with changes in number of parameters such as superficial velocity, metal oxide concentration, reactor temperature, etc. For the experiments of Mattisson et al. (2001), detailed time varying outlet concentration values were compared, and it was found that CFD simulations provided a reasonable match with this data.

  16. Computational Thermochemistry of Jet Fuels and Rocket Propellants

    NASA Technical Reports Server (NTRS)

    Crawford, T. Daniel

    2002-01-01

    The design of new high-energy density molecules as candidates for jet and rocket fuels is an important goal of modern chemical thermodynamics. The NASA Glenn Research Center is home to a database of thermodynamic data for over 2000 compounds related to this goal, in the form of least-squares fits of heat capacities, enthalpies, and entropies as functions of temperature over the range of 300 - 6000 K. The chemical equilibrium with applications (CEA) program written and maintained by researchers at NASA Glenn over the last fifty years, makes use of this database for modeling the performance of potential rocket propellants. During its long history, the NASA Glenn database has been developed based on experimental results and data published in the scientific literature such as the standard JANAF tables. The recent development of efficient computational techniques based on quantum chemical methods provides an alternative source of information for expansion of such databases. For example, it is now possible to model dissociation or combustion reactions of small molecules to high accuracy using techniques such as coupled cluster theory or density functional theory. Unfortunately, the current applicability of reliable computational models is limited to relatively small molecules containing only around a dozen (non-hydrogen) atoms. We propose to extend the applicability of coupled cluster theory- often referred to as the 'gold standard' of quantum chemical methods- to molecules containing 30-50 non-hydrogen atoms. The centerpiece of this work is the concept of local correlation, in which the description of the electron interactions- known as electron correlation effects- are reduced to only their most important localized components. Such an advance has the potential to greatly expand the current reach of computational thermochemistry and thus to have a significant impact on the theoretical study of jet and rocket propellants.

  17. 10 CFR Appendix II to Part 504 - Fuel Price Computation

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... provide the procedure to: (1) Calculate fuel price and inflation indices; (2) account for projected real... example fuel price and inflation indices based on the latest data appearing in the Energy Information Administration's (EIA) Annual Energy Outlook (AEO). The fuel price and inflation indices will change yearly with...

  18. 3-Dimensional Computational Fluid Dynamics Modeling of Solid Oxide Fuel Cell Using Different Fuels

    DTIC Science & Technology

    2011-01-01

    major types of fuel cells in practice are listed below: Polymer Electrolyte Membrane Fuel Cell ( PEMFC ) Alkaline Fuel cell (AFC) Phosphoric Acid...Material Operating Temperature (oC) Efficiency (%) PEMFC H2, Methanol, Formic Acid Hydrated Organic Polymer < 90 40-50 AFC Pure H2 Aqueous

  19. A computational method for optimizing fuel treatment locations

    Treesearch

    Mark A. Finney

    2006-01-01

    Modeling and experiments have suggested that spatial fuel treatment patterns can influence the movement of large fires. On simple theoretical landscapes consisting of two fuel types (treated and untreated) optimal patterns can be analytically derived that disrupt fire growth efficiently (i.e. with less area treated than random patterns). Although conceptually simple,...

  20. Use of Computational Fluid Dynamics (CFD) tools for fuel assembly analysis.

    SciTech Connect

    Garner, P. L.; Sofu, T.; Nuclear Engineering Division

    2004-01-01

    The STAR-CD computer program for Computational Fuel Dynamics (CFD) has been applied to the Russian pin-type fuel assemblies proposed as low enriched uranium (LEU) replacements for the high enriched uranium (HEU) (36%) IRT-3M fuel assemblies currently used in the WWR-SM reactor in Uzbekistan. For fuel assemblies containing twisted, finned pin-type fuel, STAR-CD was first used to model the single pin having the highest power density along with its associated coolant as an isolated unit cell. Velocity, pressure, temperature, heat flux, etc. were calculated on a detailed spatial basis in the coolant, cladding, and fuel. The model was then expanded to include multiple fuel pins; the computed motion of coolant from one portion of the assembly to another can reduce the peak temperatures below what one would compute using a single-pin model and, thus, change conclusions regarding the margin to onset of nucleate boiling. STAR-CD has also been applied to the IRT-3M tube-type fuel assemblies in the current HEU core.

  1. TRANS4: a computer code calculation of solid fuel penetration of a concrete barrier. [LMFBR; GCFR

    SciTech Connect

    Ono, C. M.; Kumar, R.; Fink, J. K.

    1980-07-01

    The computer code, TRANS4, models the melting and penetration of a solid barrier by a solid disc of fuel following a core disruptive accident. This computer code has been used to model fuel debris penetration of basalt, limestone concrete, basaltic concrete, and magnetite concrete. Sensitivity studies were performed to assess the importance of various properties on the rate of penetration. Comparisons were made with results from the GROWS II code.

  2. Development of a novel computational tool for optimizing the operation of fuel cells systems: Application for phosphoric acid fuel cells

    NASA Astrophysics Data System (ADS)

    Zervas, P. L.; Tatsis, A.; Sarimveis, H.; Markatos, N. C. G.

    Fuel cells offer a significant and promising clean technology for portable, automotive and stationary applications and, thus, optimization of their performance is of particular interest. In this study, a novel optimization tool is developed that realistically describes and optimizes the performance of fuel cell systems. First, a 3D steady-state detailed model is produced based on computational fluid dynamics (CFD) techniques. Simulated results obtained from the CFD model are used in a second step, to generate a database that contains the fuel and oxidant volumetric rates and utilizations and the corresponding cell voltages. In the third step mathematical relationships are developed between the input and output variables, using the database that has been generated in the previous step. In particular, the linear regression methodology and the radial basis function (RBF) neural network architecture are utilized for producing the input-output "meta-models". Several statistical tests are used to validate the proposed models. Finally, a multi-objective hierarchical Non-Linear Programming (NLP) problem is formulated that takes into account the constraints and limitations of the system. The multi-objective hierarchical approach is built upon two steps: first, the fuel volumetric rate is minimized, recognizing the fact that our first concern is to reduce consumption of the expensive fuel. In the second step, optimization is performed with respect to the oxidant volumetric rate. The proposed method is illustrated through its application for phosphoric acid fuel cell (PAFC) systems.

  3. TEMP: a computer code to calculate fuel pin temperatures during a transient. [LMFBR

    SciTech Connect

    Bard, F E; Christensen, B Y; Gneiting, B C

    1980-04-01

    The computer code TEMP calculates fuel pin temperatures during a transient. It was developed to accommodate temperature calculations in any system of axi-symmetric concentric cylinders. When used to calculate fuel pin temperatures, the code will handle a fuel pin as simple as a solid cylinder or as complex as a central void surrounded by fuel that is broken into three regions by two circumferential cracks. Any fuel situation between these two extremes can be analyzed along with additional cladding, heat sink, coolant or capsule regions surrounding the fuel. The one-region version of the code accurately calculates the solution to two problems having closed-form solutions. The code uses an implicit method, an explicit method and a Crank-Nicolson (implicit-explicit) method.

  4. Modification of a fuel-cell engine for control by a digital computer

    NASA Technical Reports Server (NTRS)

    Hagedorn, N. H.

    1972-01-01

    A manually operated fuel-cell system was modified to be monitored and controlled by a digital computer. The purpose was to have a test item with which to study possible system-computer interface problems. The modification consisted of installing solenoid valves, circuitry, transducers, and limit switches on the system. These modifications permit computer control of load current, reactant purge, water removal, and electrolyte concentration and computer initiation of system shutdown.

  5. Use of refinery computer model to predict fuel production

    NASA Technical Reports Server (NTRS)

    Flores, F. J.

    1979-01-01

    Several factors (crudes, refinery operation and specifications) that affect yields and properties of broad specification jet fuel were parameterized using the refinery simulation model which can simulate different types of refineries were used to make the calculations. Results obtained from the program are used to correlate yield as a function of final boiling point, hydrogen content and freezing point for jet fuels produced in two refinery configurations, each one processing a different crude mix. Refinery performances are also compared in terms of energy consumption.

  6. Computational and Experimental Studies of Jet Fuel Combustion

    DTIC Science & Technology

    2009-08-14

    reference flame with a prescribed velocity and thermal field and then to perturb such a flame with known amounts of either jet fuel or surrogates. This... thermal conductivity (TCD), flame ionization (FID) and mass spectrometry detectors (MSD) (Agilent 5973N). The instrument can separate and quantify...location of the peak temperature was approached. This sequence was in line with the anticipated kinetic behavior based on thermal decomposition of

  7. Fuel burnup analysis for Thai research reactor by using MCNPX computer code

    NASA Astrophysics Data System (ADS)

    Sangkaew, S.; Angwongtrakool, T.; Srimok, B.

    2017-06-01

    This paper presents the fuel burnup analysis of the Thai research reactor (TRR-1/M1), TRIGA Mark-III, operated by Thailand Institute of Nuclear Technology (TINT) in Bangkok, Thailand. The modelling software used in this analysis is MCNPX (MCNP eXtended) version 2.6.0, a Fortran90 Monte Carlo radiation transport computer code. The analysis results will cover the core excess reactivity, neutron fluxes at the irradiation positions and neutron detector tubes, power distribution, fuel burnup, and fission products based on fuel cycle of first reactor core arrangement.

  8. The GC computer code for flow sheet simulation of pyrochemical processing of spent nuclear fuels

    SciTech Connect

    Ahluwalia, R.K.; Geyer, H.K.

    1996-11-01

    The GC computer code has been developed for flow sheet simulation of pyrochemical processing of spent nuclear fuel. It utilizes a robust algorithm SLG for analyzing simultaneous chemical reactions between species distributed across many phases. Models have been developed for analysis of the oxide fuel reduction process, salt recovery by electrochemical decomposition of lithium oxide, uranium separation from the reduced fuel by electrorefining, and extraction of fission products into liquid cadmium. The versatility of GC is demonstrated by applying the code to a flow sheet of current interest.

  9. Computations of spray, fuel-air mixing, and combustion in a lean-premixed-prevaporized combustor

    NASA Technical Reports Server (NTRS)

    Dasgupta, A.; Li, Z.; Shih, T. I.-P.; Kundu, K.; Deur, J. M.

    1993-01-01

    A code was developed for computing the multidimensional flow, spray, combustion, and pollutant formation inside gas turbine combustors. The code developed is based on a Lagrangian-Eulerian formulation and utilizes an implicit finite-volume method. The focus of this paper is on the spray part of the code (both formulation and algorithm), and a number of issues related to the computation of sprays and fuel-air mixing in a lean-premixed-prevaporized combustor. The issues addressed include: (1) how grid spacings affect the diffusion of evaporated fuel, and (2) how spurious modes can arise through modelling of the spray in the Lagrangian computations. An upwind interpolation scheme is proposed to account for some effects of grid spacing on the artificial diffusion of the evaporated fuel. Also, some guidelines are presented to minimize errors associated with the spurious modes.

  10. Direct Methanol Fuel Cell Power Supply For All-Day True Wireless Mobile Computing

    SciTech Connect

    Brian Wells

    2008-11-30

    PolyFuel has developed state-of-the-art portable fuel cell technology for the portable computing market. A novel approach to passive water recycling within the MEA has led to significant system simplification and size reduction. Miniature stack technology with very high area utilization and minimalist seals has been developed. A highly integrated balance of plant with very low parasitic losses has been constructed around the new stack design. Demonstration prototype systems integrated with laptop computers have been shown in recent months to leading OEM computer manufacturers. PolyFuel intends to provide this technology to its customers as a reference design as a means of accelerating the commercialization of portable fuel cell technology. The primary goal of the project was to match the energy density of a commercial lithium ion battery for laptop computers. PolyFuel made large strides against this goal and has now demonstrated 270 Wh/liter compared with lithium ion energy densities of 300 Wh/liter. Further, more incremental, improvements in energy density are envisioned with an additional 20-30% gains possible in each of the next two years given further research and development.

  11. NASA/MSFC multilayer diffusion models and computer program for operational prediction of toxic fuel hazards

    NASA Technical Reports Server (NTRS)

    Dumbauld, R. K.; Bjorklund, J. R.; Bowers, J. F.

    1973-01-01

    The NASA/MSFC multilayer diffusion models are discribed which are used in applying meteorological information to the estimation of toxic fuel hazards resulting from the launch of rocket vehicle and from accidental cold spills and leaks of toxic fuels. Background information, definitions of terms, description of the multilayer concept are presented along with formulas for determining the buoyant rise of hot exhaust clouds or plumes from conflagrations, and descriptions of the multilayer diffusion models. A brief description of the computer program is given, and sample problems and their solutions are included. Derivations of the cloud rise formulas, users instructions, and computer program output lists are also included.

  12. Computational study of fuel injection in a shcramjet inlet

    NASA Astrophysics Data System (ADS)

    Parent, Bernard

    The primary objective of this investigation is to present the mixing of fuel with air in the inlet of a shock-induced combustion ramjet (shcramjet). The study is limited to non-reacting hydrogen-air mixing in an external-compression inlet at a flight Mach number of 11 and at a dynamic pressure of 1400 psf (67032 Pa), using an array of cantilevered ramp injectors. A numerical method based on the Yee-Roe scheme and block-implicit approximate factorization is developed to solve the FANS equations closed by the Wilcox ko turbulence model. A new acceleration technique for streamwise-separated hypersonic flow, dubbed the "marching window", is presented. The dilatational dissipation correction is seen to affect the mixing efficiency considerably for a cantilevered ramp injector flowfield even at a vanishing convective Mach number, due to the high turbulent Mach number generated by the high cross-stream shear induced by the ramp-generated axial vortices. Due to the fuel being injected at a very high speed, fuel injection in the inlet is found to increase considerably the thrust potential, with a gain exceeding the loss by 40--120%. Losses due to skin friction are seen to play a significant role in the inlet, as they are estimated to make up as much as 50--70% of the thrust potential losses. The use of a turbulence model that can predict accurately the wall shear stress is hence crucial in assessing the losses accurately in a shcramjet inlet. Substituting the second inlet shock by a Prandtl-Meyer compression fan is encouraged as it decreases the thrust potential losses, reduces the risk of premature ignition by reducing the static temperature, while decreasing the mixing efficiency by a mere 6%. One approach that is observed herein to be successful at increasing the mixing efficiency in the inlet is by alternating the injection angle along the injector array. The use of two injection angles of 9 and 16 degrees is seen to result in a 32% increase in the mixing efficiency at

  13. Computer control of fuel handling activities at FFTF

    SciTech Connect

    Romrell, D.M.

    1985-03-01

    The Fast Flux Test Facility near Richland, Washington, utilizes computer control for reactor refueling and other related core component handling and processing tasks. The computer controlled tasks described in this paper include core component transfers within the reactor vessel, core component transfers into and out of the reactor vessel, remote duct measurements of irradiated core components, remote duct cutting, and finally, transferring irradiated components out of the reactor containment building for off-site shipments or to long term storage. 3 refs., 16 figs.

  14. Proton exchange membrane fuel cell degradation: A parametric analysis using Computational Fluid Dynamics

    NASA Astrophysics Data System (ADS)

    Ozden, Ender; Tari, Ilker

    2016-02-01

    A Polymer Electrolyte Membrane (PEM) fuel cell is numerically investigated both as fresh and as degraded with the help of observed degradation patterns reported in the literature. The fresh fuel cell model is validated and verified with the data from the literature. Modifying the model by varying the parameters affected by degradation, a degraded PEM fuel cell model is created. The degraded fuel cell is parametrically analyzed by using a commercial Computational Fluid Dynamics (CFD) software. The investigated parameters are the membrane equivalent weight, the Catalyst Layer (CL) porosity and viscous resistance, the Gas Diffusion Layer (GDL) porosity and viscous resistance, and the bipolar plate contact resistance. It is shown for the first time that PEM fuel cell overall degradation can be numerically estimated by combining experimental data from degraded individual components. By comparing the simulation results for the fresh and the degraded PEM fuel cells for two years of operation, it is concluded that the effects of overall degradation on cell potential is significant - estimated to be 17% around the operating point of the fuel cell at 0.95 V open circuit voltage and 70 °C operating temperature.

  15. Computed tomography measurement of gaseous fuel concentration by infrared laser light absorption

    NASA Astrophysics Data System (ADS)

    Kawazoe, Hiromitsu; Inagaki, Kazuhisa; Emi, Y.; Yoshino, Fumio

    1997-11-01

    A system to measure gaseous hydrocarbon distributions was devised, which is based on IR light absorption by C-H stretch mode of vibration and computed tomography method. It is called IR-CT method in the paper. Affection of laser light power fluctuation was diminished by monitoring source light intensity by the second IR light detector. Calibration test for methane fuel was carried out to convert spatial data of line absorption coefficient into quantitative methane concentration. This system was applied to three flow fields. The first is methane flow with lifted flame which is generated by a gourd-shaped fuel nozzle. Feasibility of the IR-CT method was confirmed through the measurement. The second application is combustion field with diffusion flame. Calibration to determine absorptivity was undertaken, and measured line absorption coefficient was converted spatial fuel concentration using corresponding temperature data. The last case is modeled in cylinder gas flow of internal combustion engine, where gaseous methane was led to the intake valve in steady flow state. The fuel gas flow simulates behavior of gaseous gasoline which is evaporated at intake valve tulip. Computed tomography measurement of inner flow is essentially difficult because of existence of surrounding wall. In this experiment, IR laser beam was led to planed portion by IR light fiber. It is found that fuel convection by airflow takes great part in air-fuel mixture formation and the developed IR-CT system to measure fuel concentration is useful to analyze air-fuel mixture formation process and to develop new combustors.

  16. Neutron Computed Tomography of Freeze/thaw Phenomena in Polymer Electrolyte Fuel Cells

    SciTech Connect

    Matthew M. Mech; Jack Brenizer; Kenan Unlu; A.K. Heller

    2008-12-12

    This report summarizes the final year's progress of the three-year NEER program. The overall objectives of this program were to 1) design and construct a sophisticated hight-resolution neutron computed tomography (NCT) facility, 2) develop novel and sophisticated liquid water and ice quantification analysis software for computed tomography, and 3) apply the advanced software and NCT capability to study liquid and ice distribution in polymer electrolyte fuel cells (PEFCs) under cold-start conditions. These objectives have been accomplished by the research team, enabling a new capability for advanced 3D image quantification with neutron imaging for fuel cell and other applications. The NCT water quantification methodology and software will greatly add to the capabilities of the neutron imaging community, and the quantified liquid water and ice distribution provided by its application to PEFCs will enhance understanding and guide design in the fuel cell community.

  17. Manual of phosphoric acid fuel cell power plant cost model and computer program

    NASA Technical Reports Server (NTRS)

    Lu, C. Y.; Alkasab, K. A.

    1984-01-01

    Cost analysis of phosphoric acid fuel cell power plant includes two parts: a method for estimation of system capital costs, and an economic analysis which determines the levelized annual cost of operating the system used in the capital cost estimation. A FORTRAN computer has been developed for this cost analysis.

  18. Computer technique for simulating the combustion of cellulose and other fuels

    Treesearch

    Andrew M. Stein; Brian W. Bauske

    1971-01-01

    A computer method has been developed for simulating the combustion of wood and other cellulosic fuels. The products of combustion are used as input for a convection model that slimulates real fires. The method allows the chemical process to proceed to equilibrium and then examines the effects of mass addition and repartitioning on the fluid mechanics of the convection...

  19. A Primitive Variable Computer Model for Combustion within Solid Fuel Ramjets.

    DTIC Science & Technology

    1979-10-01

    INTRODUCTION-------------------------------------------1I II. MOODL OVERVIEW --------------------- 4 4 A. INTRODUCTION...oxidizer - (1 + I) kg products Fuel and oxygen, therefore, could not exist simultaneoulsy and the com- bustion process was mixing limited . In addition...geometry.and appropriate boundary conditions are summarized in figure 1. 2. Inlet Although not a computer program limitation , "plug flow" was assumed

  20. Computational modeling of alkaline air-breathing microfluidic fuel cells with an array of cylinder anodes

    NASA Astrophysics Data System (ADS)

    Ye, Ding-Ding; Zhang, Biao; Zhu, Xun; Sui, Pang-Chieh; Djilali, Ned; Liao, Qiang

    2015-08-01

    A three-dimensional computational model is developed for an alkaline air-breathing microfluidic fuel cell (AMFC) with an array of cylinder anodes. The model is validated against experimental data from an in-house prototype AMFC. The distributions of fluid velocity, fuel concentration and current density of the fuel cell are analyzed in detail. The effect of reactant flow rate on the cell performance and electrode potentials is also studied. The model results suggest that fuel crossover is minimized by the fast electrolyte flow in the vicinity of the cathode. The current production of each anode is uneven and is well correlated with internal ohmic resistance. Fuel transfer limitation occurs at low flow rates (<100 μL min-1) but diminishes at high flow rates. The model results also indicate that cathode potential reversal takes place at combined low flow rate and high current density conditions, mainly due to the improved overpotential downstream where fuel starvation occurs. The anode reaction current distribution is found to be relatively uniform, which is a result of a compensating mechanism that improves the current production of the bottom anodes downstream.

  1. Computational fluid dynamics capability for the solid-fuel ramjet projectile

    NASA Astrophysics Data System (ADS)

    Nusca, Michael J.; Chakravarthy, Sukumar R.; Goldberg, Uriel C.

    1990-06-01

    A computational fluid dynamics solution of the Navier-Stokes equations has been applied to the internal and external flow of inert solid-fuel ramjet projectiles. Computational modeling reveals internal flowfield details not attainable by flight or wind tunnel measurements, thus contributing to the current investigation into the flight performance of solid-fuel ramjet projectiles. The present code employs numerical algorithms termed total variational diminishing (TVD). Computational solutions indicate the importance of several special features of the code including the zonal grid framework, the TVD scheme, and a recently developed backflow turbulence model. The solutions are compared with results of internal surface pressure measurements. As demonstrated by these comparisons, the use of a backflow turbulence model distinguishes between satisfactory and poor flowfield predictions.

  2. Computation of Dancoff Factors for Fuel Elements Incorporating Randomly Packed TRISO Particles

    SciTech Connect

    J. L. Kloosterman; Abderrafi M. Ougouag

    2005-01-01

    A new method for estimating the Dancoff factors in pebble beds has been developed and implemented within two computer codes. The first of these codes, INTRAPEB, is used to compute Dancoff factors for individual pebbles taking into account the random packing of TRISO particles within the fuel zone of the pebble and explicitly accounting for the finite geometry of the fuel kernels. The second code, PEBDAN, is used to compute the pebble-to-pebble contribution to the overall Dancoff factor. The latter code also accounts for the finite size of the reactor vessel and for the proximity of reflectors, as well as for fluctuations in the pebble packing density that naturally arises in pebble beds.

  3. Reliability computing of polymer-electrolyte-membrane fuel cell stacks through Petri nets

    NASA Astrophysics Data System (ADS)

    Wieland, C.; Schmid, O.; Meiler, M.; Wachtel, A.; Linsler, D.

    In this paper a model is introduced which computes reliability data of PEMFC (polymer-electrolyte-membrane fuel cell) stacks, especially the average lifetime of a single stack or the reliability of stacks of a whole fuel cell vehicle fleet within a given timing. The stack and its behaviour over time is modelled by a Petri net. The behaviour is divided into degradation, spontaneous and reversible events. Through the worsening over time the characteristics voltage, internal and external leakages, which are assigned to the components MEA (membrane electrolyte assembly) and BIP (bipolar plate), are changed. Thresholds for every characteristic monitor the operating ability of the whole stack.

  4. Literature review of United States utilities computer codes for calculating actinide isotope content in irradiated fuel

    SciTech Connect

    Horak, W.C.; Lu, Ming-Shih

    1991-12-01

    This paper reviews the accuracy and precision of methods used by United States electric utilities to determine the actinide isotopic and element content of irradiated fuel. After an extensive literature search, three key code suites were selected for review. Two suites of computer codes, CASMO and ARMP, are used for reactor physics calculations; the ORIGEN code is used for spent fuel calculations. They are also the most widely used codes in the nuclear industry throughout the world. Although none of these codes calculate actinide isotopics as their primary variables intended for safeguards applications, accurate calculation of actinide isotopic content is necessary to fulfill their function.

  5. Demonstration of Emitted-Neutron Computed Tomography to Count Fuel Pins

    SciTech Connect

    Hausladen, Paul; Blackston, Matthew A; Brubaker, E.; Chichester, David; Marleau, P.; Newby, Robert Jason

    2012-01-01

    In this paper, we report demonstration of emitted-neutron computed tomography using fast fission neutrons to infer the geometry of sources of special nuclear material (SNM) such as fuel pins. In a proof-of-concept measurement at the Idaho National Laboratory s (INL s) Zero Power Physics Reactor (ZPPR) facility, an array of unirradiated Pu MOX fuel rodlets in a soup can were imaged, and a bias defect consisting of a single rodlet containing Pu replaced by one containing depleted uranium (DU) was detected. The imaging system employed in the demonstration is based on a newly constructed array of pixelated neutron detectors that are suitable for arrangement in a close-packed imaging array and whose active volume consists of liquid scintillator EJ-309 which allows neutron-gamma discrimination via pulse shape to enable pure fast-neutron imaging. The imaging array was used along with a radial collimator aperture in order to perform high quality fast-neutron imaging where tomographic reconstruction of slices through an object resolve neutron sources similar in dimension to a fuel pellet, or about 1 cm. Measurements were performed at Oak Ridge National Laboratory (ORNL) with neutron sources in addition to those performed at the INL s ZPPR facility with Pu MOX fuel rodlets. An analogous capability to detect single-pin defects in spent fuel assemblies would be desirable, such as for safeguards verification measurements of spent fuel assemblies just prior to transferring them from the spent fuel cooling pool to long term dry cask storage. This paper describes the design and construction of the present imager, characterization measurements with neutron sources at ORNL, measurements with SNM at INL s ZPPR facility, and feasibility of building an analogous imager for spent fuel measurements.

  6. Demonstration of Emitted-Neutron Computed Tomography to Count Fuel Pins

    SciTech Connect

    P. A. Hausladen; M. A. Blackston; E. Brubaker; D. L. Chichester; P. Marleau; R. J. Newby

    2012-07-01

    In this paper, we report demonstration of emitted-neutron computed tomography using fast fission neutrons to infer the geometry of sources of special nuclear material (SNM) such as fuel pins. In a proof-of-concept measurement at the Idaho National Laboratory’s (INL’s) Zero Power Physics Reactor (ZPPR) facility, an array of unirradiated Pu MOX fuel rodlets in a soup can were imaged, and a bias defect consisting of a single rodlet containing Pu replaced by one containing depleted uranium (DU) was detected. The imaging system employed in the demonstration is based on a newly constructed array of pixelated neutron detectors that are suitable for arrangement in a close-packed imaging array and whose active volume consists of liquid scintillator EJ-309 which allows neutron-gamma discrimination via pulse shape to enable pure fast-neutron imaging. The imaging array was used along with a radial collimator aperture in order to perform high quality fast-neutron imaging where tomographic reconstruction of slices through an object resolve neutron sources similar in dimension to a fuel pellet, or about 1 cm. Measurements were performed at Oak Ridge National Laboratory (ORNL) with neutron sources in addition to those performed at the INL’s ZPPR facility with Pu MOX fuel rodlets. An analogous capability to detect single-pin defects in spent fuel assemblies would be desirable, such as for safeguards verification measurements of spent fuel assemblies just prior to transferring them from the spent fuel cooling pool to long term dry cask storage. This paper describes the design and construction of the present imager, characterization measurements with neutron sources at ORNL, measurements with SNM at INL’s ZPPR facility, and feasibility of building an analogous imager for spent fuel measurements.

  7. Computing Q-D Relationships for Storage of Rocket Fuels

    NASA Technical Reports Server (NTRS)

    Jester, Keith

    2005-01-01

    The Quantity Distance Measurement Tool is a GIS BASEP computer program that aids safety engineers by calculating quantity-distance (Q-D) relationships for vessels that contain explosive chemicals used in testing rocket engines. (Q-D relationships are standard relationships between specified quantities of specified explosive materials and minimum distances by which they must be separated from persons, objects, and other explosives to obtain specified types and degrees of protection.) The program uses customized geographic-information-system (GIS) software and calculates Q-D relationships in accordance with NASA's Safety Standard For Explosives, Propellants, and Pyrotechnics. Displays generated by the program enable the identification of hazards, showing the relationships of propellant-storage-vessel safety buffers to inhabited facilities and public roads. Current Q-D information is calculated and maintained in graphical form for all vessels that contain propellants or other chemicals, the explosiveness of which is expressed in TNT equivalents [amounts of trinitrotoluene (TNT) having equivalent explosive effects]. The program is useful in the acquisition, siting, construction, and/or modification of storage vessels and other facilities in the development of an improved test-facility safety program.

  8. Issues associated with modelling of proton exchange membrane fuel cell by computational fluid dynamics

    NASA Astrophysics Data System (ADS)

    Bednarek, Tomasz; Tsotridis, Georgios

    2017-03-01

    The objective of the current study is to highlight possible limitations and difficulties associated with Computational Fluid Dynamics in PEM single fuel cell modelling. It is shown that an appropriate convergence methodology should be applied for steady-state solutions, due to inherent numerical instabilities. A single channel fuel cell model has been taken as numerical example. Results are evaluated for quantitative as well qualitative points of view. The contribution to the polarization curve of the different fuel cell components such as bi-polar plates, gas diffusion layers, catalyst layers and membrane was investigated via their effects on the overpotentials. Furthermore, the potential losses corresponding to reaction kinetics, due to ohmic and mas transport limitations and the effect of the exchange current density and open circuit voltage, were also investigated. It is highlighted that the lack of reliable and robust input data is one of the issues for obtaining accurate results.

  9. Manual of phosphoric acid fuel cell stack three-dimensional model and computer program

    NASA Technical Reports Server (NTRS)

    Lu, C. Y.; Alkasab, K. A.

    1984-01-01

    A detailed distributed mathematical model of phosphoric acid fuel cell stack have been developed, with the FORTRAN computer program, for analyzing the temperature distribution in the stack and the associated current density distribution on the cell plates. Energy, mass, and electrochemical analyses in the stack were combined to develop the model. Several reasonable assumptions were made to solve this mathematical model by means of the finite differences numerical method.

  10. Creation of Computational Benchmarks for LEU and MOX Fuel Assemblies Under Accident Conditions

    SciTech Connect

    Pavlovitchev, A M; Kalashnikov, A G; Kalugin, M A; Lazarenko, A P; Maiorov, L V; Sidorenko, V D

    1999-11-01

    The result of VVER-1000 computational benchmarks, calculations obtained with the use of various Russian codes (such as MCU-RFFI/A, TVS-M and WIMS-ABBN) are presented. List of benchmarks includes LEU and MOX cells with fresh and spent fuel under various conditions (for calculation of kinetic parameters, Doppler coefficient, reactivity effect of decreasing the water density). Calculations results are compared with each other and results of this comparison are discussed.

  11. Computer model for refinery operations with emphasis on jet fuel production. Volume 1: Program description

    NASA Technical Reports Server (NTRS)

    Dunbar, D. N.; Tunnah, B. G.

    1978-01-01

    A FORTRAN computer program is described for predicting the flow streams and material, energy, and economic balances of a typical petroleum refinery, with particular emphasis on production of aviation turbine fuel of varying end point and hydrogen content specifications. The program has provision for shale oil and coal oil in addition to petroleum crudes. A case study feature permits dependent cases to be run for parametric or optimization studies by input of only the variables which are changed from the base case.

  12. Manual of phosphoric acid fuel cell power plant optimization model and computer program

    NASA Technical Reports Server (NTRS)

    Lu, C. Y.; Alkasab, K. A.

    1984-01-01

    An optimized cost and performance model for a phosphoric acid fuel cell power plant system was derived and developed into a modular FORTRAN computer code. Cost, energy, mass, and electrochemical analyses were combined to develop a mathematical model for optimizing the steam to methane ratio in the reformer, hydrogen utilization in the PAFC plates per stack. The nonlinear programming code, COMPUTE, was used to solve this model, in which the method of mixed penalty function combined with Hooke and Jeeves pattern search was chosen to evaluate this specific optimization problem.

  13. Reconstruction of limited computed tomography data of fuel cell components using Direct Iterative Reconstruction of Computed Tomography Trajectories

    NASA Astrophysics Data System (ADS)

    Lange, Axel; Kupsch, Andreas; Hentschel, Manfred P.; Manke, Ingo; Kardjilov, Nikolay; Arlt, Tobias; Grothausmann, Roman

    CT (computed tomography) reconstructions of fuel cell components of a yet unrivaled spatial resolution and quality are presented. This is achieved by application of the novel DIRECTT (Direct Iterative Reconstruction of Computed Tomography Trajectories) algorithm. We focus on two different key issues which essentially rule the fuel cell's durability on different length scales and physical interactions. On the resolution scale of some 100 μm agglomerations of condensed water in flow-field channels are detected by means of quasi- in situ neutron CT (after operation). Five orders of magnitude below nanometer sized Ru catalyst particles on carbon black support are visualized by electron tomography. Both types of experiments are especially adapted to the type of material involved but they are accompanied by severe deviations from ideal CT measuring conditions, as well. In order to overcome the tremendous reconstruction artifacts of standard algorithms, we employ DIRECTT which is described in detail. Comparisons of DIRECTT reconstructions to the conventional filtered back projection, prove the significant improvements in both experimental methods.

  14. Open-source computational model of a solid oxide fuel cell

    NASA Astrophysics Data System (ADS)

    Beale, Steven B.; Choi, Hae-Won; Pharoah, Jon G.; Roth, Helmut K.; Jasak, Hrvoje; Jeon, Dong Hyup

    2016-03-01

    The solid oxide fuel cell is an electro-chemical device which converts chemical energy into electricity and heat. To compete in today's market, design improvements, in terms of performance and life cycle, are required. Numerical prototypes can accelerate design and development progress. In this programme of research, a three-dimensional solid oxide fuel cell prototype, openFuelCell, based on open-source computational fluid dynamics software was developed and applied to a single cell. Transport phenomena, combined with the solution to the local Nernst equation for the open-circuit potential, as well as the Kirchhoff-Ohm relationship for the local current density, allow local electro-chemistry, fluid flow, multi-component species transport, and multi-region thermal analysis to be considered. The underlying physicochemical hydrodynamics, including porous-electrode and electro-chemical effects are described in detail. The openFuelCell program is developed in an object-oriented open-source C++ library. The code is available at http://openfuelcell.sourceforge.net/. The paper also describes domain decomposition techniques considered in the context of highly efficient parallel programming.

  15. Evaluation of Computed Tomography of Mock Uranium Fuel Rods at the Advanced Photon Source

    DOE PAGES

    Hunter, James F.; Brown, Donald William; Okuniewski, Maria

    2015-06-01

    This study discusses a multi-year effort to evaluate the utility of computed tomography at the Advanced Photon Source (APS) as a tool for non-destructive evaluation of uranium based fuel rods. The majority of the data presented is on mock material made with depleted uranium which mimics the x-ray attenuation characteristics of fuel rods while allowing for simpler handling. A range of data is presented including full thickness (5mm diameter) fuel rodlets, reduced thickness (1.8mm) sintering test samples, and pre/post irradiation samples (< 1mm thick). These data were taken on both a white beam (bending magnet) beamline and a high energy,more » monochromatic beamline. This data shows the utility of a synchrotron type source in the evealuation of manufacturing defects (pre-irradiation) and lays out the case for in situ CT of fuel pellet sintering. Finally, in addition data is shown from small post-irradiation samples and a case is made for post-irradiation CT of larger samples.« less

  16. Evaluation of Computed Tomography of Mock Uranium Fuel Rods at the Advanced Photon Source

    SciTech Connect

    Hunter, James F.; Brown, Donald William; Okuniewski, Maria

    2015-06-01

    This study discusses a multi-year effort to evaluate the utility of computed tomography at the Advanced Photon Source (APS) as a tool for non-destructive evaluation of uranium based fuel rods. The majority of the data presented is on mock material made with depleted uranium which mimics the x-ray attenuation characteristics of fuel rods while allowing for simpler handling. A range of data is presented including full thickness (5mm diameter) fuel rodlets, reduced thickness (1.8mm) sintering test samples, and pre/post irradiation samples (< 1mm thick). These data were taken on both a white beam (bending magnet) beamline and a high energy, monochromatic beamline. This data shows the utility of a synchrotron type source in the evealuation of manufacturing defects (pre-irradiation) and lays out the case for in situ CT of fuel pellet sintering. Finally, in addition data is shown from small post-irradiation samples and a case is made for post-irradiation CT of larger samples.

  17. Three-dimensional Computational Fluid Dynamics (CFD) modeling of dry spent nuclear fuel storage canisters

    SciTech Connect

    Lee, S.Y.

    1997-06-01

    One of the interim storage configurations being considered for aluminum-clad foreign research reactor fuel, such as the Material and Testing Reactor (MTR) design, is in a dry storage facility. To support design studies of storage options, a computational and experimental program was conducted at the Savannah River Site (SRS). The objective was to develop computational fluid dynamics (CFD) models which would be benchmarked using data obtained from a full scale heat transfer experiment conducted in the SRS Experimental Thermal Fluids Laboratory. The current work documents the CFD approach and presents comparison of results with experimental data. CFDS-FLOW3D (version 3.3) CFD code has been used to model the 3-dimensional convective velocity and temperature distributions within a single dry storage canister of MTR fuel elements. For the present analysis, the Boussinesq approximation was used for the consideration of buoyancy-driven natural convection. Comparison of the CFD code can be used to predict reasonably accurate flow and thermal behavior of a typical foreign research reactor fuel stored in a dry storage facility.

  18. FRAPCON-2: A Computer Code for the Calculation of Steady State Thermal-Mechanical Behavior of Oxide Fuel Rods

    SciTech Connect

    Berna, G. A; Bohn, M. P.; Rausch, W. N.; Williford, R. E.; Lanning, D. D.

    1981-01-01

    FRAPCON-2 is a FORTRAN IV computer code that calculates the steady state response of light Mater reactor fuel rods during long-term burnup. The code calculates the temperature, pressure, deformation, and tai lure histories of a fuel rod as functions of time-dependent fuel rod power and coolant boundary conditions. The phenomena modeled by the code include (a) heat conduction through the fuel and cladding, (b) cladding elastic and plastic deformation, (c) fuel-cladding mechanical interaction, (d) fission gas release, (e} fuel rod internal gas pressure, (f) heat transfer between fuel and cladding, (g) cladding oxidation, and (h) heat transfer from cladding to coolant. The code contains necessary material properties, water properties, and heat transfer correlations. FRAPCON-2 is programmed for use on the CDC Cyber 175 and 176 computers. The FRAPCON-2 code Is designed to generate initial conditions for transient fuel rod analysis by either the FRAP-T6 computer code or the thermal-hydraulic code, RELAP4/MOD7 Version 2.

  19. Experimental and Computational Study on the Cusp-DEC and TWDEC for Advanced Fueled Fusion

    SciTech Connect

    Tomita, Y.; Yasaka, Y.; Takeno, H.; Ishikawa, M.; Nemoto, T.

    2005-01-15

    Experimental and computational results of direct energy converters (DECs) for advanced fueled fusion such as D-{sup 3}He are presented. Kinetic energy of thermal component of end loss plasma is converted to electricity by using the Cusp DEC. The proof-of-principle experiments of a single slanted cusp have been carried out and verified the faculty of the configuration. To improve a separation of electrons from ions, numerical simulation shows a Helmholtz magnetic configuration with a uniform magnetic field is more effective than the Cusp DEC. The fusion-produced high-energy ions like 15 MeV protons in D-{sup 3}He fueled fusion can pass through the Cusp DEC without disturbing their orbits and enter a traveling-wave direct energy converter (TWDEC). Small scale experiments have shown the effectiveness of the TWDEC and the numerical simulation on optimization of interval of electrodes in a decelerator gives high conversion efficiency up to 60 %.

  20. Computer modeling of single-cell and multicell thermionic fuel elements

    SciTech Connect

    Dickinson, J.W.; Klein, A.C.

    1996-05-01

    Modeling efforts are undertaken to perform coupled thermal-hydraulic and thermionic analysis for both single-cell and multicell thermionic fuel elements (TFE). The analysis--and the resulting MCTFE computer code (multicell thermionic fuel element)--is a steady-state finite volume model specifically designed to analyze cylindrical TFEs. It employs an interactive successive overrelaxation solution technique to solve for the temperatures throughout the TFE and a coupled thermionic routine to determine the total TFE performance. The calculated results include temperature distributions in all regions of the TFE, axial interelectrode voltages and current densities, and total TFE electrical output parameters including power, current, and voltage. MCTFE-generated results compare experimental data from the single-cell Topaz-II-type TFE and multicell data from the General Atomics 3H5 TFE to benchmark the accuracy of the code methods.

  1. COXPRO-II: a computer program for calculating radiation and conduction heat transfer in irradiated fuel assemblies

    SciTech Connect

    Rhodes, C.A.

    1984-12-01

    This report describes the computer program COXPRO-II, which was written for performing thermal analyses of irradiated fuel assemblies in a gaseous environment with no forced cooling. The heat transfer modes within the fuel pin bundle are radiation exchange among fuel pin surfaces and conduction by the stagnant gas. The array of parallel cylindrical fuel pins may be enclosed by a metal wrapper or shroud. Heat is dissipated from the outer surface of the fuel pin assembly by radiation and convection. Both equilateral triangle and square fuel pin arrays can be analyzed. Steady-state and unsteady-state conditions are included. Temperatures predicted by the COXPRO-II code have been validated by comparing them with experimental

  2. Computational modeling of transport and electrochemical reactions in proton-exchange membrane fuel cells

    NASA Astrophysics Data System (ADS)

    Um, Sukkee

    A comprehensive, multi-physics computational fuel cell dynamics (CFCD) model integrating electrochemical kinetics, charge transport, mass transport (particularly water transport), and flow dynamics is developed in this thesis. The numerical model is validated against published experimental data and utilized to generate results that reveal the internal operation of a PEM fuel cell. A number of model applications are demonstrated in the present work. First, the CFCD model is applied to explore hydrogen dilution effects in the anode feed. Detailed two-dimensional electrochemical and flow/transport simulations are provided to examine substantial anode concentration polarization due to hydrogen depletion at the reaction sites. A transient simulation of the cell current response to a step change in cell voltage is also attempted to elucidate characteristics of the dynamic response of a fuel cell for the first time. After the two-dimensional computational study, the CFCD model is applied to illustrate three-dimensional interactions between mass transfer and electrochemical kinetics. Emphasis is placed on obtaining a fundamental understanding of fully three-dimensional flow in the air cathode with interdigitated flowfield design and how it impacts the transport and electrochemical reaction processes. The innovative design concept for enhanced oxygen transport to, and effective water removal from the cathode, is explored numerically. Next, an analytical study of water transport is performed to investigate various water transport regimes of practical interest. The axial locations characteristic of anode water loss and cathode flooding are predicted theoretically and compared with numerical results. A continuous stirred fuel cell reactor (CSFCR) model is also proposed for the limiting situation where the anode and cathode sides reach equilibrium in water concentration with a thin ionomer membrane in between. In addition to the analytical solutions, a detailed water transport

  3. Computer-based phosphoric acid fuel cell analytical tools Descriptions and usages

    NASA Technical Reports Server (NTRS)

    Lu, C.; Presler, A. F.

    1987-01-01

    Simulation models have been developed for the prediction of phosphoric acid fuel cell (PAFC) powerplant system performance under both transient and steady operation conditions, as well as for the design of component configurations and for optimal systems synthesis. These models, which are presently computer-implemented, are an engineering and a system model; the former being solved by the finite difference method to determine the balances and properties of different sections, and the latter using thermodynamic balances to set up algebraic equations that yield physical and chemical properties of the stream for one operating condition.

  4. Computer-based phosphoric acid fuel cell analytical tools Descriptions and usages

    NASA Technical Reports Server (NTRS)

    Lu, C.; Presler, A. F.

    1987-01-01

    Simulation models have been developed for the prediction of phosphoric acid fuel cell (PAFC) powerplant system performance under both transient and steady operation conditions, as well as for the design of component configurations and for optimal systems synthesis. These models, which are presently computer-implemented, are an engineering and a system model; the former being solved by the finite difference method to determine the balances and properties of different sections, and the latter using thermodynamic balances to set up algebraic equations that yield physical and chemical properties of the stream for one operating condition.

  5. Computational fluid dynamic analysis of a High-Velocity Oxygen-Fuel (HVOF) thermal spray torch

    SciTech Connect

    Hassan, B.; Oberkampf, W.L.; Neiser, R.A.; Roemer, T.J.

    1995-09-01

    The gas dynamics of a High-Velocity Oxygen-Fuel (HVOF) torch are analyzed using computational fluid dynamics (CFD) techniques. The thermal spray device analyzed is similar to a Metco Diamond Jet torch with powder feed. The injection nozzle is assumed to be axisymmetric with premixed fuel and oxygen fed from an annulus, and air cooling injected along the interior surface of the aircap. The aircap, a cronically converging nozzle, achieves choked flow conditions at the exit and a supersonic, under-expanded jet develops externally. Finite difference equations for mass, momentum, and energy conservation are solved for the gas dynamics. The combustion process is modeled using a single-step and a 12-step quasi-global finite-rate chemistry model with dissociation of the gas and a total of nine species. Turbulent flow inside the aircap and in the free-jet decay is modeled using a two-equation k-{epsilon} model. An iterative, implicit, finite volume numerical method is used to solve the gas dynamic equations inside and outside the torch . The CFD results are compared with recent experimental measurements of pressure inside the HVOF aircap. Comparisons are made for two flow rates of premixed fuel and oxygen and air cooling. This paper presents the first published comparisons of CFD predictions and experimental measurements for HVOF tbermal spraying.

  6. Personal computer based decision support system for routing nuclear spent fuel

    SciTech Connect

    Chin, Shih-Miao; Joy, D.S.; Johnson, P.E. ); Bobic, S.M.; Miaou, Shaw-Pin . Transportation Center)

    1989-11-14

    An approach has been formulated to route nuclear spent fuel over the US Interstate highway network. This approach involves the generation of alternative routes so that any potential adverse impacts will not only concentrate on regions along the shortest path between the nuclear power plant and repository. Extensive literature research on the shortest path finding algorithms has been carried out. Consequently, an extremely efficient shortest path algorithm has been implemented and significantly increases the overall system performance. State-of-the-art interactive computer graphics is used. In addition to easy-to-use pop-up menus, full color mapping and display capabilities are also incorporated. All of these features have been implemented on commonly available personal computers. 6 figs., 2 tabs.

  7. Transient computation fluid dynamics modeling of a single proton exchange membrane fuel cell with serpentine channel

    NASA Astrophysics Data System (ADS)

    Hu, Guilin; Fan, Jianren

    The proton exchange membrane fuel cell (PEMFC) has become a promising candidate for the power source of electrical vehicles because of its low pollution, low noise and especially fast startup and transient responses at low temperatures. A transient, three-dimensional, non-isothermal and single-phase mathematical model based on computation fluid dynamics has been developed to describe the transient process and the dynamic characteristics of a PEMFC with a serpentine fluid channel. The effects of water phase change and heat transfer, as well as electrochemical kinetics and multicomponent transport on the cell performance are taken into account simultaneously in this comprehensive model. The developed model was employed to simulate a single laboratory-scale PEMFC with an electrode area about 20 cm 2. The dynamic behavior of the characteristic parameters such as reactant concentration, pressure loss, temperature on the membrane surface of cathode side and current density during start-up process were computed and are discussed in detail. Furthermore, transient responses of the fuel cell characteristics during step changes and sinusoidal changes in the stoichiometric flow ratio of the cathode inlet stream, cathode inlet stream humidity and cell voltage are also studied and analyzed and interesting undershoot/overshoot behavior of some variables was found. It was also found that the startup and transient response time of a PEM fuel cell is of the order of a second, which is similar to the simulation results predicted by most models. The result is an important guide for the optimization of PEMFC designs and dynamic operation.

  8. DNA molecule provides a computing machine with both data and fuel

    NASA Astrophysics Data System (ADS)

    Benenson, Yaakov; Adar, Rivka; Paz-Elizur, Tamar; Livneh, Zvi; Shapiro, Ehud

    2003-03-01

    The unique properties of DNA make it a fundamental building block in the fields of supramolecular chemistry, nanotechnology, nano-circuits, molecular switches, molecular devices, and molecular computing. In our recently introduced autonomous molecular automaton, DNA molecules serve as input, output, and software, and the hardware consists of DNA restriction and ligation enzymes using ATP as fuel. In addition to information, DNA stores energy, available on hybridization of complementary strands or hydrolysis of its phosphodiester backbone. Here we show that a single DNA molecule can provide both the input data and all of the necessary fuel for a molecular automaton. Each computational step of the automaton consists of a reversible software molecule/input molecule hybridization followed by an irreversible software-directed cleavage of the input molecule, which drives the computation forward by increasing entropy and releasing heat. The cleavage uses a hitherto unknown capability of the restriction enzyme FokI, which serves as the hardware, to operate on a noncovalent software/input hybrid. In the previous automaton, software/input ligation consumed one software molecule and two ATP molecules per step. As ligation is not performed in this automaton, a fixed amount of software and hardware molecules can, in principle, process any input molecule of any length without external energy supply. Our experiments demonstrate 3 × 1012 automata per μl performing 6.6 × 1010 transitions per second per μl with transition fidelity of 99.9%, dissipating about 5 × 10-9 W/μl as heat at ambient temperature.

  9. DNA molecule provides a computing machine with both data and fuel.

    PubMed

    Benenson, Yaakov; Adar, Rivka; Paz-Elizur, Tamar; Livneh, Zvi; Shapiro, Ehud

    2003-03-04

    The unique properties of DNA make it a fundamental building block in the fields of supramolecular chemistry, nanotechnology, nano-circuits, molecular switches, molecular devices, and molecular computing. In our recently introduced autonomous molecular automaton, DNA molecules serve as input, output, and software, and the hardware consists of DNA restriction and ligation enzymes using ATP as fuel. In addition to information, DNA stores energy, available on hybridization of complementary strands or hydrolysis of its phosphodiester backbone. Here we show that a single DNA molecule can provide both the input data and all of the necessary fuel for a molecular automaton. Each computational step of the automaton consists of a reversible software molecule input molecule hybridization followed by an irreversible software-directed cleavage of the input molecule, which drives the computation forward by increasing entropy and releasing heat. The cleavage uses a hitherto unknown capability of the restriction enzyme FokI, which serves as the hardware, to operate on a noncovalent software input hybrid. In the previous automaton, software input ligation consumed one software molecule and two ATP molecules per step. As ligation is not performed in this automaton, a fixed amount of software and hardware molecules can, in principle, process any input molecule of any length without external energy supply. Our experiments demonstrate 3 x 10(12) automata per microl performing 6.6 x 10(10) transitions per second per microl with transition fidelity of 99.9%, dissipating about 5 x 10(-9) W microl as heat at ambient temperature.

  10. Computationally efficient modeling of the dynamic behavior of a portable PEM fuel cell stack

    NASA Astrophysics Data System (ADS)

    Philipps, S. P.; Ziegler, C.

    A numerically efficient mathematical model of a proton exchange membrane fuel cell (PEMFC) stack is presented. The aim of this model is to study the dynamic response of a PEMFC stack subjected to load changes under the restriction of short computing time. This restriction was imposed in order for the model to be applicable for nonlinear model predictive control (NMPC). The dynamic, non-isothermal model is based on mass and energy balance equations, which are reduced to ordinary differential equations in time. The reduced equations are solved for a single cell and the results are upscaled to describe the fuel cell stack. This approach makes our calculations computationally efficient. We study the feasibility of capturing water balance effects with such a reduced model. Mass balance equations for water vapor and liquid water including the phase change as well as a steady-state membrane model accounting for the electro-osmotic drag and diffusion of water through the membrane are included. Based on this approach the model is successfully used to predict critical operating conditions by monitoring the amount of liquid water in the stack and the stack impedance. The model and the overall calculation method are validated using two different load profiles on realistic time scales of up to 30 min. The simulation results are used to clarify the measured characteristics of the stack temperature and the stack voltage, which has rarely been done on such long time scales. In addition, a discussion of the influence of flooding and dry-out on the stack voltage is included. The modeling approach proves to be computationally efficient: an operating time of 0.5 h is simulated in less than 1 s, while still showing sufficient accuracy.

  11. Computational modeling of intermediate temperature proton exchange membrane (PEM) fuel cells

    NASA Astrophysics Data System (ADS)

    Cheddie, Denver Faron

    A two-phase three-dimensional computational model of an intermediate temperature (120--190°C) proton exchange membrane (PEM) fuel cell is presented. This represents the first attempt to model PEM fuel cells employing intermediate temperature membranes, in this case, phosphoric acid doped polybenzimidazole (PBI). To date, mathematical modeling of PEM fuel cells has been restricted to low temperature operation, especially to those employing Nafion RTM membranes; while research on PBI as an intermediate temperature membrane has been solely at the experimental level. This work is an advancement in the state of the art of both these fields of research. With a growing trend toward higher temperature operation of PEM fuel cells, mathematical modeling of such systems is necessary to help hasten the development of the technology and highlight areas where research should be focused. This mathematical model accounted for all the major transport and polarization processes occurring inside the fuel cell, including the two phase phenomenon of gas dissolution in the polymer electrolyte. Results were presented for polarization performance, flux distributions, concentration variations in both the gaseous and aqueous phases, and temperature variations for various heat management strategies. The model predictions matched well with published experimental data, and were self-consistent. The major finding of this research was that, due to the transport limitations imposed by the use of phosphoric acid as a doping agent, namely low solubility and diffusivity of dissolved gases and anion adsorption onto catalyst sites, the catalyst utilization is very low (˜1--2%). Significant cost savings were predicted with the use of advanced catalyst deposition techniques that would greatly reduce the eventual thickness of the catalyst layer, and subsequently improve catalyst utilization. The model also predicted that an increase in power output in the order of 50% is expected if alternative doping

  12. Application of High Performance Computing for Simulating Cycle-to-Cycle Variation in Dual-Fuel Combustion Engines

    DOE PAGES

    Jupudi, Ravichandra S.; Finney, Charles E.A.; Primus, Roy; ...

    2016-04-05

    Interest in operational cost reduction is driving engine manufacturers to consider lower-cost fuel substitution in heavy-duty diesel engines. These dual-fuel (DF) engines could be operated either in diesel-only mode or operated with premixed natural gas (NG) ignited by a pilot flame of compression-ignited direct-injected diesel fuel. One promising application is that of large-bore, medium-speed engines such as those used in locomotives. With realistic natural gas substitution levels in the fleet of locomotives currently in service, such fuel substitution could result in billions of dollars of savings annually in the US alone. However, under certain conditions, dual-fuel operation can result inmore » increased cycle-to-cycle variability (CCV) during combustion, resulting in variations in cylinder pressure and work extraction. In certain situations, the CCV of dual-fuel operation can be notably higher than that of diesel-only combustion under similar operating conditions. Excessive CCV can limit the NG substitution rate and operating range of a dual-fuel engine by increasing emissions and reducing engine stability, reliability and fuel efficiency via incomplete natural-gas combustion. Running multiple engine cycles in series to simulate CCV can be quite time consuming. Hence innovative modelling techniques and large computing resources are needed to investigate the factors affecting CCV in dual-fuel engines. This paper discusses the use of the High Performance Computing resource Titan, at the Oak Ridge Leadership Computing Facility at Oak Ridge National Laboratory, to investigate cycle-to-cycle combustion variability of a dual-fuel engine. The CONVERGE CFD software was used to simulate multiple, parallel single cycles of dual-fuel combustion with perturbed operating parameters and boundary conditions. These perturbations are imposed according to a sparse grids sampling of the parameter space. The sampling scheme chosen is similar to a design of experiments method

  13. Application of High Performance Computing for Simulating Cycle-to-Cycle Variation in Dual-Fuel Combustion Engines

    SciTech Connect

    Jupudi, Ravichandra S.; Finney, Charles E.A.; Primus, Roy; Wijeyakulasuriya, Sameera; Klingbeil, Adam E.; Tamma, Bhaskar; Stoyanov, Miroslav K.

    2016-04-05

    Interest in operational cost reduction is driving engine manufacturers to consider lower-cost fuel substitution in heavy-duty diesel engines. These dual-fuel (DF) engines could be operated either in diesel-only mode or operated with premixed natural gas (NG) ignited by a pilot flame of compression-ignited direct-injected diesel fuel. One promising application is that of large-bore, medium-speed engines such as those used in locomotives. With realistic natural gas substitution levels in the fleet of locomotives currently in service, such fuel substitution could result in billions of dollars of savings annually in the US alone. However, under certain conditions, dual-fuel operation can result in increased cycle-to-cycle variability (CCV) during combustion, resulting in variations in cylinder pressure and work extraction. In certain situations, the CCV of dual-fuel operation can be notably higher than that of diesel-only combustion under similar operating conditions. Excessive CCV can limit the NG substitution rate and operating range of a dual-fuel engine by increasing emissions and reducing engine stability, reliability and fuel efficiency via incomplete natural-gas combustion. Running multiple engine cycles in series to simulate CCV can be quite time consuming. Hence innovative modelling techniques and large computing resources are needed to investigate the factors affecting CCV in dual-fuel engines. This paper discusses the use of the High Performance Computing resource Titan, at the Oak Ridge Leadership Computing Facility at Oak Ridge National Laboratory, to investigate cycle-to-cycle combustion variability of a dual-fuel engine. The CONVERGE CFD software was used to simulate multiple, parallel single cycles of dual-fuel combustion with perturbed operating parameters and boundary conditions. These perturbations are imposed according to a sparse grids sampling of the parameter space. The sampling scheme chosen is similar to a design of experiments method but uses

  14. Three-Dimensional Ignition and Flame Propagation Above Liquid Fuel Pools: Computational Analysis

    NASA Technical Reports Server (NTRS)

    Cai, Jinsheng; Sirignano, William A.

    2001-01-01

    A three-dimensional unsteady reactive Navier-Stokes code is developed to study the ignition and flame spread above liquid fuels initially below the flashpoint temperature. Opposed air flow to the flame spread due to forced and/or natural convection is considered. Pools of finite width and length are studied in air channels of prescribed height and width. Three-dimensional effects of the flame front near the edge of the pool are captured in the computation. The formation of a recirculation zone in the gas phase similar to that found in two-dimensional calculations is also present in the three-dimensional calculations. Both uniform spread and pulsating spread modes are found in the calculated results.

  15. Computational Methods for Nanoscale X-ray Computed Tomography Image Analysis of Fuel Cell and Battery Materials

    NASA Astrophysics Data System (ADS)

    Kumar, Arjun S.

    Over the last fifteen years, there has been a rapid growth in the use of high resolution X-ray computed tomography (HRXCT) imaging in material science applications. We use it at nanoscale resolutions up to 50 nm (nano-CT) for key research problems in large scale operation of polymer electrolyte membrane fuel cells (PEMFC) and lithium-ion (Li-ion) batteries in automotive applications. PEMFC are clean energy sources that electrochemically react with hydrogen gas to produce water and electricity. To reduce their costs, capturing their electrode nanostructure has become significant in modeling and optimizing their performance. For Li-ion batteries, a key challenge in increasing their scope for the automotive industry is Li metal dendrite growth. Li dendrites are structures of lithium with 100 nm features of interest that can grow chaotically within a battery and eventually lead to a short-circuit. HRXCT imaging is an effective diagnostics tool for such applications as it is a non-destructive method of capturing the 3D internal X-ray absorption coefficient of materials from a large series of 2D X-ray projections. Despite a recent push to use HRXCT for quantitative information on material samples, there is a relative dearth of computational tools in nano-CT image processing and analysis. Hence, we focus on developing computational methods for nano-CT image analysis of fuel cell and battery materials as required by the limitations in material samples and the imaging environment. The first problem we address is the segmentation of nano-CT Zernike phase contrast images. Nano-CT instruments are equipped with Zernike phase contrast optics to distinguish materials with a low difference in X-ray absorption coefficient by phase shifting the X-ray wave that is not diffracted by the sample. However, it creates image artifacts that hinder the use of traditional image segmentation techniques. To restore such images, we setup an inverse problem by modeling the X-ray phase contrast

  16. COBRA-SFS (Spent Fuel Storage): A thermal-hydraulic analysis computer code: Volume 3, Validation assessments

    SciTech Connect

    Lombardo, N.J.; Cuta, J.M.; Michener, T.E.; Rector, D.R.; Wheeler, C.L.

    1986-12-01

    This report presents the results of the COBRA-SFS (Spent Fuel Storage) computer code validation effort. COBRA-SFS, while refined and specialized for spent fuel storage system analyses, is a lumped-volume thermal-hydraulic analysis computer code that predicts temperature and velocity distributions in a wide variety of systems. Through comparisons of code predictions with spent fuel storage system test data, the code's mathematical, physical, and mechanistic models are assessed, and empirical relations defined. The six test cases used to validate the code and code models include single-assembly and multiassembly storage systems under a variety of fill media and system orientations and include unconsolidated and consolidated spent fuel. In its entirety, the test matrix investigates the contributions of convection, conduction, and radiation heat transfer in spent fuel storage systems. To demonstrate the code's performance for a wide variety of storage systems and conditions, comparisons of code predictions with data are made for 14 runs from the experimental data base. The cases selected exercise the important code models and code logic pathways and are representative of the types of simulations required for spent fuel storage system design and licensing safety analyses. For each test, a test description, a summary of the COBRA-SFS computational model, assumptions, and correlations employed are presented. For the cases selected, axial and radial temperature profile comparisons of code predictions with test data are provided, and conclusions drawn concerning the code models and the ability to predict the data and data trends. Comparisons of code predictions with test data demonstrate the ability of COBRA-SFS to successfully predict temperature distributions in unconsolidated or consolidated single and multiassembly spent fuel storage systems.

  17. RISKIND: A computer program for calculating radiological consequences and health risks from transportation of spent nuclear fuel

    SciTech Connect

    Yuan, Y.C.; Chen, S.Y.; LePoire, D.J.; Rothman, R.

    1993-02-01

    This report presents the technical details of RISIUND, a computer code designed to estimate potential radiological consequences and health risks to individuals and the collective population from exposures associated with the transportation of spent nuclear fuel. RISKIND is a user-friendly, semiinteractive program that can be run on an IBM or equivalent personal computer. The program language is FORTRAN-77. Several models are included in RISKIND that have been tailored to calculate the exposure to individuals under various incident-free and accident conditions. The incidentfree models assess exposures from both gamma and neutron radiation and can account for different cask designs. The accident models include accidental release, atmospheric transport, and the environmental pathways of radionuclides from spent fuels; these models also assess health risks to individuals and the collective population. The models are supported by databases that are specific to spent nuclear fuels and include a radionudide inventory and dose conversion factors.

  18. TRUMP-BD: A computer code for the analysis of nuclear fuel assemblies under severe accident conditions

    SciTech Connect

    Lombardo, N.J.; Marseille, T.J.; White, M.D.; Lowery, P.S.

    1990-06-01

    TRUMP-BD (Boil Down) is an extension of the TRUMP (Edwards 1972) computer program for the analysis of nuclear fuel assemblies under severe accident conditions. This extension allows prediction of the heat transfer rates, metal-water oxidation rates, fission product release rates, steam generation and consumption rates, and temperature distributions for nuclear fuel assemblies under core uncovery conditions. The heat transfer processes include conduction in solid structures, convection across fluid-solid boundaries, and radiation between interacting surfaces. Metal-water reaction kinetics are modeled with empirical relationships to predict the oxidation rates of steam-exposed Zircaloy and uranium metal. The metal-water oxidation models are parabolic in form with an Arrhenius temperature dependence. Uranium oxidation begins when fuel cladding failure occurs; Zircaloy oxidation occurs continuously at temperatures above 13000{degree}F when metal and steam are available. From the metal-water reactions, the hydrogen generation rate, total hydrogen release, and temporal and spatial distribution of oxide formations are computed. Consumption of steam from the oxidation reactions and the effect of hydrogen on the coolant properties is modeled for independent coolant flow channels. Fission product release from exposed uranium metal Zircaloy-clad fuel is modeled using empirical time and temperature relationships that consider the release to be subject to oxidation and volitization/diffusion ( bake-out'') release mechanisms. Release of the volatile species of iodine (I), tellurium (Te), cesium (Ce), ruthenium (Ru), strontium (Sr), zirconium (Zr), cerium (Cr), and barium (Ba) from uranium metal fuel may be modeled.

  19. Determination of Optimal Parameters for Dual-Layer Cathode of Polymer Electrolyte Fuel Cell Using Computational Intelligence-Aided Design

    PubMed Central

    Chen, Yi; Huang, Weina; Peng, Bei

    2014-01-01

    Because of the demands for sustainable and renewable energy, fuel cells have become increasingly popular, particularly the polymer electrolyte fuel cell (PEFC). Among the various components, the cathode plays a key role in the operation of a PEFC. In this study, a quantitative dual-layer cathode model was proposed for determining the optimal parameters that minimize the over-potential difference and improve the efficiency using a newly developed bat swarm algorithm with a variable population embedded in the computational intelligence-aided design. The simulation results were in agreement with previously reported results, suggesting that the proposed technique has potential applications for automating and optimizing the design of PEFCs. PMID:25490761

  20. Determination of optimal parameters for dual-layer cathode of polymer electrolyte fuel cell using computational intelligence-aided design.

    PubMed

    Chen, Yi; Huang, Weina; Peng, Bei

    2014-01-01

    Because of the demands for sustainable and renewable energy, fuel cells have become increasingly popular, particularly the polymer electrolyte fuel cell (PEFC). Among the various components, the cathode plays a key role in the operation of a PEFC. In this study, a quantitative dual-layer cathode model was proposed for determining the optimal parameters that minimize the over-potential difference η and improve the efficiency using a newly developed bat swarm algorithm with a variable population embedded in the computational intelligence-aided design. The simulation results were in agreement with previously reported results, suggesting that the proposed technique has potential applications for automating and optimizing the design of PEFCs.

  1. Computational And Experimental Studies Of Three-Dimensional Flame Spread Over Liquid Fuel Pools

    NASA Technical Reports Server (NTRS)

    Ross, Howard D. (Technical Monitor); Cai, Jinsheng; Liu, Feng; Sirignano, William A.; Miller, Fletcher J.

    2003-01-01

    Schiller, Ross, and Sirignano (1996) studied ignition and flame spread above liquid fuels initially below the flashpoint temperature by using a two-dimensional computational fluid dynamics code that solves the coupled equations of both the gas and the liquid phases. Pulsating flame spread was attributed to the establishment of a gas-phase recirculation cell that forms just ahead of the flame leading edge because of the opposing effect of buoyancy-driven flow in the gas phase and the thermocapillary-driven flow in the liquid phase. Schiller and Sirignano (1996) extended the same study to include flame spread with forced opposed flow in the gas phase. A transitional flow velocity was found above which an originally uniform spreading flame pulsates. The same type of gas-phase recirculation cell caused by the combination of forced opposed flow, buoyancy-driven flow, and thermocapillary-driven concurrent flow was responsible for the pulsating flame spread. Ross and Miller (1998) and Miller and Ross (1998) performed experimental work that corroborates the computational findings of Schiller, Ross, and Sirignano (1996) and Schiller and Sirignano (1996). Cai, Liu, and Sirignano (2002) developed a more comprehensive three-dimensional model and computer code for the flame spread problem. Many improvements in modeling and numerical algorithms were incorporated in the three-dimensional model. Pools of finite width and length were studied in air channels of prescribed height and width. Significant three-dimensional effects around and along the pool edge were observed. The same three-dimensional code is used to study the detailed effects of pool depth, pool width, opposed air flow velocity, and different levels of air oxygen concentration (Cai, Liu, and Sirignano, 2003). Significant three-dimensional effects showing an unsteady wavy flame front for cases of wide pool width are found for the first time in computation, after being noted previously by experimental observers (Ross

  2. Addressing the challenges of solar thermal fuels via atomic-scale computational design and experiment

    NASA Astrophysics Data System (ADS)

    Kolpak, Alexie; Kucharski, Timothy; Grossman, Jeffrey

    2012-02-01

    By reversibly storing solar energy in the conformations of photo-isomers, solar thermal fuels (STFs) provide a mechanism for emissions-free, renewable energy storage and conversion in a single system. Development of STFs as a large-scale energy technology has been hampered by technical challenges that beset the photo-isomers of interest: low energy density, storage lifetime, and quantum yield; UV absorption; and irreversible degradation upon repeated cycling. In this talk, we discuss our efforts to design new STFs that overcome these hurdles. We present computational results on various STFs based on our recently proposed photo-isomer/template STF concept [Kolpak and Grossman, Nano Letters 11, 3156 (2011)], as well as new experimental results on azobenzene-functionalized carbon nanotube STFs. Our approach yields significant improvements with respect to STFs studied in the past, with energy densities similar to Li-ion batteries, storage lifetimes > 1 year, and increased quantum yield and absorption efficiency. Our strategy also suggests mechanisms for inhibiting photo-isomer degradation. With a large phase space yet to be explored, there remain numerous possibilites for property enhancement, suggesting that STFs could become a competitive renewable energy technology.

  3. Computational fluid dynamics analysis in microbial fuel cells with different anode configurations.

    PubMed

    Kim, Jiyeon; Kim, Hongsuck; Kim, Byunggoon; Yu, Jaecheul

    2014-01-01

    A key criterion in microbial fuel cell (MFC) design is that the bio-electrochemical reaction between bacteria and the bulk solution should occur evenly on the electrode surface in order to improve electricity generation. However, experimental optimization of MFC design over a wide range of conditions is limited. Computational fluid dynamics (CFD) technology makes it possible to evaluate physicochemical phenomena such as fluid flows, mass transfer and chemical reaction, which can assist in system optimization. Twelve MFCs (M1-M12) with different internal structures were subjected to CFD analysis. The dead (DS) and working spaces (WS) of the anode compartment were calculated. The flow patterns of the anodic fluid varied according to the internal structures. The WS where the bio-electrochemical reaction can actually occur varied over the range of 0.14-0.57 m(2). Based on the above results, the power densities were estimated under the assumption that a monolayer biofilm was formed on the electrode. M11, with 18 rectangular-type internal structures, showed the largest WS of 0.57 m(2) and a theoretical maximum power density of 0.54 W/m(2). Although the optimization of the MFC configuration with only CFD analysis remains limited, the present study results are expected to provide fundamental data for MFC optimization.

  4. COBRA-SFS (Spent Fuel Storage): A thermal-hydraulic analysis computer code: Volume 2, User's manual

    SciTech Connect

    Rector, D.R.; Cuta, J.M.; Lombardo, N.J.; Michener, T.E.; Wheeler, C.L.

    1986-11-01

    COBRA-SFS (Spent Fuel Storage) is a general thermal-hydraulic analysis computer code used to predict temperatures and velocities in a wide variety of systems. The code was refined and specialized for spent fuel storage system analyses for the US Department of Energy's Commercial Spent Fuel Management Program. The finite-volume equations governing mass, momentum, and energy conservation are written for an incompressible, single-phase fluid. The flow equations model a wide range of conditions including natural circulation. The energy equations include the effects of solid and fluid conduction, natural convection, and thermal radiation. The COBRA-SFS code is structured to perform both steady-state and transient calculations; however, the transient capability has not yet been validated. This volume contains the input instructions for COBRA-SFS and an auxiliary radiation exchange factor code, RADX-1. It is intended to aid the user in becoming familiar with the capabilities and modeling conventions of the code.

  5. COBRA-SFS (Spent Fuel Storage): A thermal-hydraulic analysis computer code: Volume 1, Mathematical models and solution method

    SciTech Connect

    Rector, D.R.; Wheeler, C.L.; Lombardo, N.J.

    1986-11-01

    COBRA-SFS (Spent Fuel Storage) is a general thermal-hydraulic analysis computer code used to predict temperatures and velocities in a wide variety of systems. The code was refined and specialized for spent fuel storage system analyses for the US Department of Energy's Commercial Spent Fuel Management Program. The finite-volume equations governing mass, momentum, and energy conservation are written for an incompressible, single-phase fluid. The flow equations model a wide range of conditions including natural circulation. The energy equations include the effects of solid and fluid conduction, natural convection, and thermal radiation. The COBRA-SFS code is structured to perform both steady-state and transient calculations: however, the transient capability has not yet been validated. This volume describes the finite-volume equations and the method used to solve these equations. It is directed toward the user who is interested in gaining a more complete understanding of these methods.

  6. GPU Based General-Purpose Parallel computing to Solve Nuclear Reactor In-Core fuel Management Design and Operation Problem

    NASA Astrophysics Data System (ADS)

    Prayudhatama, D.; Waris, A.; Kurniasih, N.; Kurniadi, R.

    2010-06-01

    In-core fuel management study is a crucial activity in nuclear power plant design and operation. Its common problem is to find an optimum arrangement of fuel assemblies inside the reactor core. Main objective for this activity is to reduce the cost of generating electricity, which can be done by altering several physical properties of the nuclear reactor without violating any of the constraints imposed by operational and safety considerations. This research try to address the problem of nuclear fuel arrangement problem, which is, leads to the multi-objective optimization problem. However, the calculation of the reactor core physical properties itself is a heavy computation, which became obstacle in solving the optimization problem by using genetic algorithm optimization. This research tends to address that problem by using the emerging General Purpose Computation on Graphics Processing Units (GPGPU) techniques implemented by C language for CUDA (Compute Unified Device Architecture) parallel programming. By using this parallel programming technique, we develop parallelized nuclear reactor fitness calculation, which is involving numerical finite difference computation. This paper describes current prototype of the parallel algorithm code we have developed on CUDA, that performs one hundreds finite difference calculation for nuclear reactor fitness evaluation in parallel by using GPU G9 Hardware Series developed by NVIDIA.

  7. GPU Based General-Purpose Parallel computing to Solve Nuclear Reactor In-Core fuel Management Design and Operation Problem

    SciTech Connect

    Prayudhatama, D.; Waris, A.; Kurniasih, N.; Kurniadi, R.

    2010-06-22

    In-core fuel management study is a crucial activity in nuclear power plant design and operation. Its common problem is to find an optimum arrangement of fuel assemblies inside the reactor core. Main objective for this activity is to reduce the cost of generating electricity, which can be done by altering several physical properties of the nuclear reactor without violating any of the constraints imposed by operational and safety considerations. This research try to address the problem of nuclear fuel arrangement problem, which is, leads to the multi-objective optimization problem. However, the calculation of the reactor core physical properties itself is a heavy computation, which became obstacle in solving the optimization problem by using genetic algorithm optimization.This research tends to address that problem by using the emerging General Purpose Computation on Graphics Processing Units (GPGPU) techniques implemented by C language for CUDA (Compute Unified Device Architecture) parallel programming. By using this parallel programming technique, we develop parallelized nuclear reactor fitness calculation, which is involving numerical finite difference computation. This paper describes current prototype of the parallel algorithm code we have developed on CUDA, that performs one hundreds finite difference calculation for nuclear reactor fitness evaluation in parallel by using GPU G9 Hardware Series developed by NVIDIA.

  8. A systematic experimental and computational investigation of a class of contoured wall fuel injectors

    NASA Technical Reports Server (NTRS)

    Waitz, Ian A.; Marble, Frank E.; Zukoski, Edward E.

    1992-01-01

    The performance of contoured wall fuel injectors for scramjet engine applications is considered. These fuel injectors were aimed at augmenting mixing through axial vorticity production arising from interaction of the fuel/air interface with an oblique shock. The effects of incoming boundary layer height, injector spacing, and injectant to freestream pressure and velocity ratios are examined. Results from 3D flow field surveys and Navier-Stokes simulations are presented.

  9. Computer simulation of thermal modelling of alkaline hydrogen/oxygen fuel cells

    NASA Astrophysics Data System (ADS)

    Baumann, A.; Hauff, S.; Bolwin, K.

    1991-11-01

    An essential problem connected with the operation of regenerative fuel cell systems in space is the rejection of waste heat, produced mainly during discharging the regenerative fuel cell. The intention of this investigation was to gain a better understanding of the heat generation and heat rejection mechanism in alkaline fuel cells by performing detailed thermal modeling of a single cell stack. In particular, spatial temperature profiles within the fuel cell stack and the start-up behavior of the cells were predicted. Furthermore a model simulation of an emergency situation due to a partial failure of the coolant circuit was performed and theoretically temperature versus time curves were given for restarting the cooling.

  10. Investigation of the Feasibility of Utilizing Gamma Emission Computed Tomography in Evaluating Fission Product Migration in Irradiated TRISO Fuel Experiments

    SciTech Connect

    Jason M. Harp; Paul A. Demkowicz

    2014-10-01

    In the High Temperature Gas-Cooled Reactor (HTGR) the TRISO particle fuel serves as the primary fission product containment. However the large number of TRISO particles present in proposed HTGRs dictates that there will be a small fraction (~10-4 to 10-5) of as manufactured and in-pile particle failures that will lead to some fission product release. The matrix material surrounding the TRISO particles in fuel compacts and the structural graphite holding the TRISO particles in place can also serve as sinks for containing any released fission products. However data on the migration of solid fission products through these materials is lacking. One of the primary goals of the AGR-3/4 experiment is to study fission product migration from failed TRISO particles in prototypic HTGR components such as structural graphite and compact matrix material. In this work, the potential for a Gamma Emission Computed Tomography (GECT) technique to non-destructively examine the fission product distribution in AGR-3/4 components and other irradiation experiments is explored. Specifically, the feasibility of using the Idaho National Laboratory (INL) Hot Fuels Examination Facility (HFEF) Precision Gamma Scanner (PGS) system for this GECT application is considered. To test the feasibility, the response of the PGS system to idealized fission product distributions has been simulated using Monte Carlo radiation transport simulations. Previous work that applied similar techniques during the AGR-1 experiment will also be discussed as well as planned uses for the GECT technique during the post irradiation examination of the AGR-2 experiment. The GECT technique has also been applied to other irradiated nuclear fuel systems that were currently available in the HFEF hot cell including oxide fuel pins, metallic fuel pins, and monolithic plate fuel.

  11. Simple computational model for the prediction of fuel pin failure during a transient-overpower accident. [LMFBR

    SciTech Connect

    Mast, P.K.

    1980-01-01

    A fuel pin failure model is developed and incorported into a fast-running computer program. The model is designed to predict irradiated fuel-pin cladding rupture during a hypothetical transient-overpower (TOP) accident in a liquid metal fast breeder reactor. The principal failure mechanisms of fuel-cladding differential thermal expansion and fission-gas pressurization are accounted for. The prediction of cladding failure is based on a mechanistic calculation of the time-dependent cladding temperature and stress. A finite-difference thermal solution is used to obtain the radial temperature distribution in the pin. The pin mechanics calculation uses a very efficient few-fuel-node/single-cladding-node algorithm that utilizes the Tresca yield criterion to determine the onset of cladding plastic deformation. Comparisons are made between model predictions and the results of a number of Transient Reactor Test Facility TOP experiments. The importance of accurately modeling the fuel radial and circumferential crack characterization is investigated and discussed. The effect of model limitations is discussed and recommendations for future work are made.

  12. Computer analysis of effects of altering jet fuel properties on refinery costs and yields

    NASA Technical Reports Server (NTRS)

    Breton, T.; Dunbar, D.

    1984-01-01

    This study was undertaken to evaluate the adequacy of future U.S. jet fuel supplies, the potential for large increases in the cost of jet fuel, and to what extent a relaxation in jet fuel properties would remedy these potential problems. The results of the study indicate that refiners should be able to meet jet fuel output requirements in all regions of the country within the current Jet A specifications during the 1990-2010 period. The results also indicate that it will be more difficult to meet Jet A specifications on the West Coast, because the feedstock quality is worse and the required jet fuel yield (jet fuel/crude refined) is higher than in the East. The results show that jet fuel production costs could be reduced by relaxing fuel properties. Potential cost savings in the East (PADDs I-IV) through property relaxation were found to be about 1.3 cents/liter (5 cents/gallon) in January 1, 1981 dollars between 1990 and 2010. However, the savings from property relaxation were all obtained within the range of current Jet A specifications, so there is no financial incentive to relax Jet A fuel specifications in the East. In the West (PADD V) the potential cost savings from lowering fuel quality were considerably greater than in the East. Cost savings from 2.7 to 3.7 cents/liter (10-14 cents/gallon) were found. In contrast to the East, on the West Coast a significant part of the savings was obtained through relaxation of the current Jet A fuel specifications.

  13. Computer model for refinery operations with emphasis on jet fuel production. Volume 3: Detailed systems and programming documentation

    NASA Technical Reports Server (NTRS)

    Dunbar, D. N.; Tunnah, B. G.

    1978-01-01

    The FORTRAN computing program predicts flow streams and material, energy, and economic balances of a typical petroleum refinery, with particular emphasis on production of aviation turbine fuels of varying end point and hydrogen content specifications. The program has a provision for shale oil and coal oil in addition to petroleum crudes. A case study feature permits dependent cases to be run for parametric or optimization studies by input of only the variables which are changed from the base case.

  14. Cosmic ray muon computed tomography of spent nuclear fuel in dry storage casks

    SciTech Connect

    Poulson, Daniel Cris; Durham, J. Matthew; Guardincerri, Elena; Morris, Christopher; Bacon, Jeffrey Darnell; Plaud-Ramos, Kenie Omar; Morley, Deborah Jean; Hecht, Adam A.

    2016-10-22

    Radiography with cosmic ray muon scattering has proven to be a successful method of imaging nuclear material through heavy shielding. Of particular interest is monitoring dry storage casks for diversion of plutonium contained in spent reactor fuel. Using muon tracking detectors that surround a cylindrical cask, cosmic ray muon scattering can be simultaneously measured from all azimuthal angles, giving complete tomographic coverage of the cask interior. This article describes the first application of filtered back projection algorithms, typically used in medical imaging, to cosmic ray muon scattering imaging. The specific application to monitoring spent nuclear fuel in dry storage casks is investigated via GEANT4 simulations. With a cylindrical muon tracking detector surrounding a typical spent fuel cask, simulations indicate that missing fuel bundles can be detected with a statistical significance of ~18σ in less than two days exposure and a sensitivity at 1σ to a 5% missing portion of a fuel bundle. Finally, we discuss potential detector technologies and geometries.

  15. FRAPCON-3: A computer code for the calculation of steady-state, thermal-mechanical behavior of oxide fuel rods for high burnup

    SciTech Connect

    Berna, G.A.; Beyer, G.A.; Davis, K.L.; Lanning, D.D.

    1997-12-01

    FRAPCON-3 is a FORTRAN IV computer code that calculates the steady-state response of light water reactor fuel rods during long-term burnup. The code calculates the temperature, pressure, and deformation of a fuel rod as functions of time-dependent fuel rod power and coolant boundary conditions. The phenomena modeled by the code include (1) heat conduction through the fuel and cladding, (2) cladding elastic and plastic deformation, (3) fuel-cladding mechanical interaction, (4) fission gas release, (5) fuel rod internal gas pressure, (6) heat transfer between fuel and cladding, (7) cladding oxidation, and (8) heat transfer from cladding to coolant. The code contains necessary material properties, water properties, and heat-transfer correlations. The codes` integral predictions of mechanical behavior have not been assessed against a data base, e.g., cladding strain or failure data. Therefore, it is recommended that the code not be used for analyses of cladding stress or strain. FRAPCON-3 is programmed for use on both mainframe computers and UNIX-based workstations such as DEC 5000 or SUN Sparcstation 10. It is also programmed for personal computers with FORTRAN compiler software and at least 8 to 10 megabytes of random access memory (RAM). The FRAPCON-3 code is designed to generate initial conditions for transient fuel rod analysis by the FRAPTRAN computer code (formerly named FRAP-T6).

  16. 3D computation of hydrogen-fueled combustion around turbine blade-effect of arrangement of injector holes-

    NASA Astrophysics Data System (ADS)

    Yamamoto, Makoto; Ikeda, Junichi; Inaba, Kazuaki

    2006-09-01

    Recently, a number of environmental problems caused from fossil fuel combustion have been focused on. In addition, with the eventual depletion of fossil energy resources, hydrogen gas is expected to be an alternative energy resource in the near future. It is characterized by high energy per unit weight, high reaction rate, wide range of flammability and the low emission property. On the other hand, many researches have been underway in several countries to improve a propulsion system for an advanced aircraft. The system is required to have higher power, lighter weight and lower emissions than existing ones. In such a future propulsion system, hydrogen gas would be one of the promising fuels for realizing the requirements. Considering these backgrounds, our group has proposed a new cycle concept for hydrogen-fueled aircraft propulsion system. In the present study, we perform 3 dimensional computations of turbulent flow fields with hydrogen-fueled combustion around a turbine blade. The main objective is to clarify the influence of arrangement of hydrogen injector holes. Changing the chordwise and spanwise spacings of the holes, the 3 dimensional nature of the flow and thermal fields is numerically studied.

  17. FuelCalc: A Method for Estimating Fuel Characteristics

    Treesearch

    Elizabeth Reinhardt; Duncan Lutes; Joe Scott

    2006-01-01

    This paper describes the FuelCalc computer program. FuelCalc is a tool to compute surface and canopy fuel loads and characteristics from inventory data, to support fuel treatment decisions by simulating effects of a wide range of silvicultural treatments on surface fuels and canopy fuels, and to provide linkages to stand visualization, fire behavior and fire effects...

  18. ROBOT3: a computer program to calculate the in-pile three-dimensional bowing of cylindrical fuel rods (AWBA Development Program)

    SciTech Connect

    Kovscek, S.E.; Martin, S.E.

    1982-10-01

    ROBOT3 is a FORTRAN computer program which is used in conjunction with the CYGRO5 computer program to calculate the time-dependent inelastic bowing of a fuel rod using an incremental finite element method. The fuel rod is modeled as a viscoelastic beam whose material properties are derived as perturbations of the CYGRO5 axisymmetric model. Fuel rod supports are modeled as displacement, force, or spring-type nodal boundary conditions. The program input is described and a sample problem is given.

  19. A computer code to estimate accidental fire and radioactive airborne releases in nuclear fuel cycle facilities: User's manual for FIRIN

    SciTech Connect

    Chan, M.K.; Ballinger, M.Y.; Owczarski, P.C.

    1989-02-01

    This manual describes the technical bases and use of the computer code FIRIN. This code was developed to estimate the source term release of smoke and radioactive particles from potential fires in nuclear fuel cycle facilities. FIRIN is a product of a broader study, Fuel Cycle Accident Analysis, which Pacific Northwest Laboratory conducted for the US Nuclear Regulatory Commission. The technical bases of FIRIN consist of a nonradioactive fire source term model, compartment effects modeling, and radioactive source term models. These three elements interact with each other in the code affecting the course of the fire. This report also serves as a complete FIRIN user's manual. Included are the FIRIN code description with methods/algorithms of calculation and subroutines, code operating instructions with input requirements, and output descriptions. 40 refs., 5 figs., 31 tabs.

  20. RISKIND: A computer program for calculating radiological consequences and health risks from transportation of spent nuclear fuel

    SciTech Connect

    Yuan, Y.C.; Chen, S.Y.; Biwer, B.M.; LePoire, D.J.

    1995-11-01

    This report presents the technical details of RISKIND, a computer code designed to estimate potential radiological consequences and health risks to individuals and the collective population from exposures associated with the transportation of spent nuclear fuel. RISKIND is a user-friendly, interactive program that can be run on an IBM or equivalent personal computer under the Windows{trademark} environment. Several models are included in RISKIND that have been tailored to calculate the exposure to individuals under various incident-free and accident conditions. The incident-free models assess exposures from both gamma and neutron radiation and can account for different cask designs. The accident models include accidental release, atmospheric transport, and the environmental pathways of radionuclides from spent fuels; these models also assess health risks to individuals and the collective population. The models are supported by databases that are specific to spent nuclear fuels and include a radionuclide inventory and dose conversion factors. In addition, the flexibility of the models allows them to be used for assessing any accidental release involving radioactive materials. The RISKIND code allows for user-specified accident scenarios as well as receptor locations under various exposure conditions, thereby facilitating the estimation of radiological consequences and health risks for individuals. Median (50% probability) and typical worst-case (less than 5% probability of being exceeded) doses and health consequences from potential accidental releases can be calculated by constructing a cumulative dose/probability distribution curve for a complete matrix of site joint-wind-frequency data. These consequence results, together with the estimated probability of the entire spectrum of potential accidents, form a comprehensive, probabilistic risk assessment of a spent nuclear fuel transportation accident.

  1. Cosmic ray muon computed tomography of spent nuclear fuel in dry storage casks

    DOE PAGES

    Poulson, Daniel Cris; Durham, J. Matthew; Guardincerri, Elena; ...

    2017-10-22

    Radiography with cosmic ray muon scattering has proven to be a successful method of imaging nuclear material through heavy shielding. Of particular interest is monitoring dry storage casks for diversion of plutonium contained in spent reactor fuel. Using muon tracking detectors that surround a cylindrical cask, cosmic ray muon scattering can be simultaneously measured from all azimuthal angles, giving complete tomographic coverage of the cask interior. This article describes the first application of filtered back projection algorithms, typically used in medical imaging, to cosmic ray muon scattering imaging. The specific application to monitoring spent nuclear fuel in dry storage casksmore » is investigated via GEANT4 simulations. With a cylindrical muon tracking detector surrounding a typical spent fuel cask, simulations indicate that missing fuel bundles can be detected with a statistical significance of ~18σ in less than two days exposure and a sensitivity at 1σ to a 5% missing portion of a fuel bundle. Finally, we discuss potential detector technologies and geometries.« less

  2. Computed isotopic inventory and dose assessment for SRS fuel and target assemblies

    SciTech Connect

    Chandler, M.C.; Ketusky, E.T.; Thoman, D.C.

    1995-06-19

    Past studies have identified and evaluated important radionuclide contributors to dose from reprocessed spent fuel sent to waste for Mark 16B and 22 fuel assemblies and for Mark 31 A and 31B target assemblies. Fission-product distributions after a 5- and 15-year decay time were calculated for a ``representative`` set of irradiation conditions (i.e., reactor power, irradiation time, and exposure) for each type of assembly. The numerical calculations were performed using the SHIELD/GLASS system of codes. The sludge and supernate source terms for dose were studied separately with the significant radionuclide contributors for each identified and evaluated. Dose analysis considered both inhalation and ingestion pathways: The inhalation pathway was analyzed for both evaporative and volatile releases. Analysis of evaporative releases utilized release fractions for the individual radionuclides as defined in the ICRP-30 by DOE guidance. A release fraction of unity was assumed for each radionuclide under volatile-type releases, which would encompass internally initiated events (e.g., fires, explosions), process-initiated events, and externally initiated events. Radionuclides which contributed at least 1% to the overall dose were designated as significant contributors. The present analysis extends and complements the past analyses through considering a broader spectrum of fuel types and a wider range of irradiation conditions. The results provide for a more thorough understanding of the influences of fuel composition and irradiation parameters on fission product distributions (at 2 years or more). Additionally, the present work allows for a more comprehensive evaluation of radionuclide contributions to dose and an estimation of the variability in the radionuclide composition of the dose source term that results from the spent fuel sent to waste encompassing a broad spectrum of fuel compositions and irradiation conditions.

  3. ADVANCING THE FUNDAMENTAL UNDERSTANDING AND SCALE-UP OF TRISO FUEL COATERS VIA ADVANCED MEASUREMENT AND COMPUTATIONAL TECHNIQUES

    SciTech Connect

    Biswas, Pratim; Al-Dahhan, Muthanna

    2012-11-01

    to advance the fundamental understanding of the hydrodynamics by systematically investigating the effect of design and operating variables, to evaluate the reported dimensionless groups as scaling factors, and to establish a reliable scale-up methodology for the TRISO fuel particle spouted bed coaters based on hydrodynamic similarity via advanced measurement and computational techniques. An additional objective is to develop an on-line non-invasive measurement technique based on gamma ray densitometry (i.e. Nuclear Gauge Densitometry) that can be installed and used for coater process monitoring to ensure proper performance and operation and to facilitate the developed scale-up methodology. To achieve the objectives set for the project, the work will use optical probes and gamma ray computed tomography (CT) (for the measurements of solids/voidage holdup cross-sectional distribution and radial profiles along the bed height, spouted diameter, and fountain height) and radioactive particle tracking (RPT) (for the measurements of the 3D solids flow field, velocity, turbulent parameters, circulation time, solids lagrangian trajectories, and many other of spouted bed related hydrodynamic parameters). In addition, gas dynamic measurement techniques and pressure transducers will be utilized to complement the obtained information. The measurements obtained by these techniques will be used as benchmark data to evaluate and validate the computational fluid dynamic (CFD) models (two fluid model or discrete particle model) and their closures. The validated CFD models and closures will be used to facilitate the developed methodology for scale-up, design and hydrodynamic similarity. Successful execution of this work and the proposed tasks will advance the fundamental understanding of the coater flow field and quantify it for proper and safe design, scale-up, and performance. Such achievements will overcome the barriers to AGR applications and will help assure that the US maintains

  4. An Optical and Computational Investigation on the Effects of Transient Fuel Injections in Internal Combustion Engines

    NASA Astrophysics Data System (ADS)

    Neal, Nicholas

    The effects of transient rate-of-injection profiles on high-pressure fuel jets have been studied in an optically accessible internal combustion engine. High-speed optical imaging measurements were applied over a range of ambient conditions, fuel types, and injection parameters. The optical data demonstrate that during the early part of the injection, while the liquid core of the jet is disintegrating, penetration is functionally linked to the orifice exit velocity up until a downstream distance hypothesized to be the jet breakup length. The jets then transition to a mixing dominated penetration behavior further downstream. Therefore, for cases that exhibit transient rate-of-injection (ROI) profiles, quasi-steady correlations for penetration have poor agreement with the empirical data. The lack of agreement between models using quasi-steady approximations and the high-speed experimental data, and the experimental evidence of liquid core physics impacting the transient jet penetration, motivated the development of a new 1-D model that integrates liquid core penetration physics and eliminates quasi-steady approximations. The new 1-D modeling methodology couples the transport equations for the evolution of the liquid core of the jet and the surrounding sheath of droplets resulting from breakup. The results of the model are validated against the aforementioned optical transient jet measurements. Finally, experimental results for two jet fuels and a diesel fuel are studied with the aid of the model. Differences in fuel properties cause the diesel fuel jet to transition from an incomplete spray to a complete spray later than the jet fuels during the transient injection process. Increasing ambient density causes the transition to happen earlier during the injection transient for all three fuels. The ignition delay and liftoff length appeared to be relatively unaffected by the late transition from incomplete to complete spray at low ambient density and low injection

  5. Computer model for refinery operations with emphasis on jet fuel production. Volume 2: Data and technical bases

    NASA Technical Reports Server (NTRS)

    Dunbar, D. N.; Tunnah, B. G.

    1978-01-01

    The FORTRAN computing program predicts the flow streams and material, energy, and economic balances of a typical petroleum refinery, with particular emphasis on production of aviation turbine fuel of varying end point and hydrogen content specifications. The program has provision for shale oil and coal oil in addition to petroleum crudes. A case study feature permits dependent cases to be run for parametric or optimization studies by input of only the variables which are changed from the base case. The report has sufficient detail for the information of most readers.

  6. A Computational and Experimental Study of Ignition Behavior of Gasoline Surrogate Fuels Under Low-Temperature Combustion Conditions

    NASA Astrophysics Data System (ADS)

    Han, J.; Haworth, D. C.; Kalaskar, V. B.; Boehman, A. L.

    2016-11-01

    One strategy for next-generation engines is low-temperature compression ignition of gasoline. Reaction pathways that are not relevant for high-temperature flame propagation are activated under these conditions, and the ignition behavior of these fuels under low-temperature conditions has not been widely explored. Here the ignition behavior of gasoline and two- and three-component surrogates has been studied experimentally and computationally over a range of operating conditions of interest for low-temperature engine combustion. Experiments were performed in a single-cylinder research engine. For each fuel blend, the critical compression ratio (lowest compression ratio at which the main ignition occurs) was determined over a range of operating conditions, by varying one parameter at a time with all other parameters held fixed. A simplified CFD model that considers detailed chemical kinetics was used to simulate the experiment. The focus of the study is to determine which surrogate fuel mixtures and chemical mechanisms are able to capture the ignition behavior of gasoline under these conditions. For example, different ignition behavior is found for different surrogate mixtures that all have the same Research Octane Number, and it is important to capture this behavior in CFD models.

  7. Transmutation Performance Analysis for Inert Matrix Fuels in Light Water Reactors and Computational Neutronics Methods Capabilities at INL

    SciTech Connect

    Michael A. Pope; Samuel E. Bays; S. Piet; R. Ferrer; Mehdi Asgari; Benoit Forget

    2009-05-01

    The urgency for addressing repository impacts has grown in the past few years as a result of Spent Nuclear Fuel (SNF) accumulation from commercial nuclear power plants. One path that has been explored by many is to eliminate the transuranic (TRU) inventory from the SNF, thus reducing the need for additional long term repository storage sites. One strategy for achieving this is to burn the separated TRU elements in the currently operating U.S. Light Water Reactor (LWR) fleet. Many studies have explored the viability of this strategy by loading a percentage of LWR cores with TRU in the form of either Mixed Oxide (MOX) fuels or Inert Matrix Fuels (IMF). A task was undertaken at INL to establish specific technical capabilities to perform neutronics analyses in order to further assess several key issues related to the viability of thermal recycling. The initial computational study reported here is focused on direct thermal recycling of IMF fuels in a heterogeneous Pressurized Water Reactor (PWR) bundle design containing Plutonium, Neptunium, Americium, and Curium (IMF-PuNpAmCm) in a multi-pass strategy using legacy 5 year cooled LWR SNF. In addition to this initial high-priority analysis, three other alternate analyses with different TRU vectors in IMF pins were performed. These analyses provide comparison of direct thermal recycling of PuNpAmCmCf, PuNpAm, PuNp, and Pu. The results of this infinite lattice assembly-wise study using SCALE 5.1 indicate that it may be feasible to recycle TRU in this manner using an otherwise typical PWR assembly without violating peaking factor limits.

  8. Computational model to predict thermal dynamics of planar solid oxide fuel cell stack during start-up process

    NASA Astrophysics Data System (ADS)

    Ki, Jeongpill; Kim, Daejong

    Solid oxide fuel cell (SOFC) systems have been recognized as the most advanced power generation system with the highest thermal efficiency with a compatibility with wide variety of hydrocarbon fuels, synthetic gas from coal, hydrogen, etc. However, SOFC requires high temperature operation to achieve high ion conductivity of ceramic electrolyte, and thus SOFC should be heated up first before fuel is supplied into the stack. This paper presents computational model for thermal dynamics of planar SOFC stack during start-up process. SOFC stack should be heated up as quickly as possible from ambient temperature to above 700 °C, while minimizing net energy consumption and thermal gradient during the heat up process. Both cathode and anode channels divided by current-collecting ribs were modeled as one-dimensional flow channels with multiple control volumes and all the solid structures were discretized into finite volumes. Two methods for stack-heating were investigated; one is with hot air through cathode channels and the other with electric heating inside a furnace. For the simulation of stack-heating with hot air, transient continuity, flow momentum, and energy equation were applied for discretized control volumes along the flow channels, and energy equations were applied to all the solid structures with appropriate heat transfer model with surrounding solid structures and/or gas channels. All transient governing equations were solved using a time-marching technique to simulate temporal evolution of temperatures of membrane-electrode-assembly (MEA), ribs, interconnects, flow channels, and solid housing structure located inside the insulating chamber. For electrical heating, uniform heat flux was applied to the stack surface with appropriate numerical control algorithm to maintain the surface temperature to certain prescribed value. The developed computational model provides very effective simulation tool to optimize stack-heating process minimizing net heating energy

  9. Evaluation of spent fuel isotopics, radiation spectra and decay heat using the scale computational system

    SciTech Connect

    Parks, C.V.; Hermann, O.W.; Ryman, J.C.

    1986-01-01

    In order to be a self-sufficient system for transport/storage cask shielding and heat transfer analysis, the SCALE system developers included modules to evaluate spent fuel radiation spectra and decay heat. The primary module developed for these analyses is ORIGEN-S which is an updated verision of the original ORIGEN code. The COUPLE module was also developed to enable ORIGEN-S to easily utilize multigroup cross sections and neutron flux data during a depletion analysis. Finally, the SAS2 control module was developed for automating the depletion and decay via ORIGEN-S while using burnup-dependent neutronic data based on a user-specified fuel assembly and reactor history. The ORIGEN-S data libraries available for depletion and decay have also been significantly updated from that developed with the original ORIGEN code.

  10. Computer program for obtaining thermodynamic and transport properties of air and products of combustion of ASTM-A-1 fuel and air

    NASA Technical Reports Server (NTRS)

    Hippensteele, S. A.; Colladay, R. S.

    1978-01-01

    A computer program for determining desired thermodynamic and transport property values by means of a three-dimensional (pressure, fuel-air ratio, and either enthalpy or temperature) interpolation routine was developed. The program calculates temperature (or enthalpy), molecular weight, viscosity, specific heat at constant pressure, thermal conductivity, isentropic exponent (equal to the specific heat ratio at conditions where gases do not react), Prandtl number, and entropy for air and a combustion gas mixture of ASTM-A-1 fuel and air over fuel-air ratios from zero to stoichiometric, pressures from 1 to 40 atm, and temperatures from 250 to 2800 K.

  11. Computational modeling study on polymer electrolyte membranes for fuel cell applications

    NASA Astrophysics Data System (ADS)

    Choe, Yoong-Kee; Tsuchida, Eiji

    2016-12-01

    Properties of polymer electrolyte membranes (PEMs) for use in polymer electrolyte membrane fuel cells (PEFCs) were investigated using the first-principles molecular dynamics simulations. One important issue in PEMs is how to improve the proton conductivity of PEMs under low hydration conditions. Results of the simulation show that perfluorinated type membranes such as Nafion exhibit excellent hydrophilic/hydrophobic phase separation while a hydrocarbon membrane has a relatively poor phase separation property. We found that such a poor phase separation behavior of a hydrocarbon membrane arise from hydrophilic functional groups attached to the PEMs.

  12. A computational and experimental study of alternative energy technologies: Constructing photochemical electron-transfer cascades and the development of computational methods for understanding fuel cell electrocatalysts

    NASA Astrophysics Data System (ADS)

    Waraksa, Chad C.

    Producing viable, vertically-integrated alternative energy systems requires solving chemical and engineering problems at many levels. This work presents experimental results seeking to make visible light driven water splitting more feasible, computational efforts aiding in the combinatorial screening of fuel cell catalysts, and a physically-realistic model of the electrochemistry at porous electrode surfaces to understand and improve the porous electrodes used in fuel cells. Combinatorial chemistry is a valuable technique for developing and screening large quantities of candidate catalysts. Data obtained from such experiments can be difficult to analyze and communicate. We implement a system to identify catalytically-active clusters within data sets and to compactly visualize four and five-metal catalytic compositions graphically as tetrahedra or animations. Combinatorially-determined catalysts are often deposited on porous electrodes providing high surface area supports for many reactions, but the influences of electrode preparation conditions on electrocatalysts are not always well understood. Electrochemical impedance spectroscopy (EIS) can provide extensive information about an electrode, but idealized models describing spectra limit the ability to draw useful conclusions. We describe a new model based on an array of parallel, non-uniform transmission lines for predicting the response of porous electrodes. The model incorporates physically realistic elements, such as discrete particles of variable size and adjustable multi-layer stacking geometries. Resistance parameters were derived from experimental data for Pt4Ru4Ir coated Ti0.9Nb0.1O 2 and Ebonex electrodes prepared under varying degrees of oxidative conditioning. The results, which indicate a high degree of impedance at the support-solution interface and consequently low catalyst utilization, suggest several strategies for improved electrode design. Fuel cells' popularity, however, is limited by the cost

  13. Experimental and computational study of methane counterflow diffusion flames perturbed by trace amounts of either jet fuel or a 6-component surrogate under non-sooting conditions

    SciTech Connect

    Bufferand, H.; Tosatto, L.; La Mantia, B.; Smooke, M.D.; Gomez, A.

    2009-08-15

    The chemical structure of a methane counterflow diffusion flame and of the same flame doped with 1000 ppm (molar) of either jet fuel or a 6-component jet fuel surrogate was analyzed experimentally, by gas sampling via quartz microprobes and subsequent GC/MS analysis, and computationally using a semi-detailed kinetic mechanism for the surrogate blend. Conditions were chosen to ensure that all three flames were non-sooting, with identical temperature profiles and stoichiometric mixture fraction, through a judicious selection of feed stream composition and strain rate. The experimental dataset provides a glimpse of the pyrolysis and oxidation behavior of jet fuel in a diffusion flame. The jet fuel initial oxidation is consistent with anticipated chemical kinetic behavior, based on thermal decomposition of large alkanes to smaller and smaller fragments and the survival of ring-stabilized aromatics at higher temperatures. The 6-component surrogate captures the same trend correctly, but the agreement is not quantitative with respect to some of the aromatics such as benzene and toluene. Various alkanes, alkenes and aromatics among the jet fuel components are either only qualitatively characterized or could not be identified, because of the presence of many isomers and overlapping spectra in the chromatogram, leaving 80% of the carbon from the jet fuel unaccounted for in the early pyrolysis history of the parent fuel. Computationally, the one-dimensional code adopted a semi-detailed kinetic mechanism for the surrogate blend that is based on an existing hierarchically constructed kinetic model for alkanes and simple aromatics, extended to account for the presence of tetralin and methylcyclohexane as reference fuels. The computational results are in reasonably good agreement with the experimental ones for the surrogate behavior, with the greatest discrepancy in the concentrations of aromatics and ethylene. (author)

  14. Fluid Flow Investigations within a 37 Element CANDU Fuel Bundle Supported by Magnetic Resonance Velocimetry and Computational Fluid Dynamics

    DOE PAGES

    Piro, M.H.A; Wassermann, F.; Grundmann, S.; ...

    2017-05-23

    The current work presents experimental and computational investigations of fluid flow through a 37 element CANDU nuclear fuel bundle. Experiments based on Magnetic Resonance Velocimetry (MRV) permit three-dimensional, three-component fluid velocity measurements to be made within the bundle with sub-millimeter resolution that are non-intrusive, do not require tracer particles or optical access of the flow field. Computational fluid dynamic (CFD) simulations of the foregoing experiments were performed with the hydra-th code using implicit large eddy simulation, which were in good agreement with experimental measurements of the fluid velocity. Greater understanding has been gained in the evolution of geometry-induced inter-subchannel mixing,more » the local effects of obstructed debris on the local flow field, and various turbulent effects, such as recirculation, swirl and separation. These capabilities are not available with conventional experimental techniques or thermal-hydraulic codes. Finally, the overall goal of this work is to continue developing experimental and computational capabilities for further investigations that reliably support nuclear reactor performance and safety.« less

  15. Computational fluid dynamics analysis of a wire-feed, high-velocity oxygen-fuel (HVOF) thermal spray torch

    SciTech Connect

    Lopez, A.R.; Hassan, B.; Oberkampf, W.L.; Neiser, R.A.; Roemer, T.J.

    1996-09-01

    The fluid and particle dynamics of a High-Velocity Oxygen-Fuel Thermal Spray torch are analyzed using computational and experimental techniques. Three-dimensional Computational Fluid Dynamics (CFD) results are presented for a curved aircap used for coating interior surfaces such as engine cylinder bores. The device analyzed is similar to the Metco Diamond Jet Rotating Wire (DJRW) torch. The feed gases are injected through an axisymmetric nozzle into the curved aircap. Premixed propylene and oxygen are introduced from an annulus in the nozzle, while cooling air is injected between the nozzle and the interior wall of the aircap. The combustion process is modeled using a single-step finite-rate chemistry model with a total of 9 gas species which includes dissociation of combustion products. A continually-fed steel wire passes through the center of the nozzle and melting occurs at a conical tip near the exit of the aircap. Wire melting is simulated computationally by injecting liquid steel particles into the flow field near the tip of the wire. Experimental particle velocity measurements during wire feed were also taken using a Laser Two-Focus (L2F) velocimeter system. Flow fields inside and outside the aircap are presented and particle velocity predictions are compared with experimental measurements outside of the aircap.

  16. Computer model predictions of the local effects of large, solid-fuel rocket motors on stratospheric ozone. Technical report

    SciTech Connect

    Zittel, P.F.

    1994-09-10

    The solid-fuel rocket motors of large space launch vehicles release gases and particles that may significantly affect stratospheric ozone densities along the vehicle's path. In this study, standard rocket nozzle and flowfield computer codes have been used to characterize the exhaust gases and particles through the afterburning region of the solid-fuel motors of the Titan IV launch vehicle. The models predict that a large fraction of the HCl gas exhausted by the motors is converted to Cl and Cl2 in the plume afterburning region. Estimates of the subsequent chemistry suggest that on expansion into the ambient daytime stratosphere, the highly reactive chlorine may significantly deplete ozone in a cylinder around the vehicle track that ranges from 1 to 5 km in diameter over the altitude range of 15 to 40 km. The initial ozone depletion is estimated to occur on a time scale of less than 1 hour. After the initial effects, the dominant chemistry of the problem changes, and new models are needed to follow the further expansion, or closure, of the ozone hole on a longer time scale.

  17. Failure analysis of fuel cell electrodes using three-dimensional multi-length scale X-ray computed tomography

    NASA Astrophysics Data System (ADS)

    Pokhrel, A.; El Hannach, M.; Orfino, F. P.; Dutta, M.; Kjeang, E.

    2016-10-01

    X-ray computed tomography (XCT), a non-destructive technique, is proposed for three-dimensional, multi-length scale characterization of complex failure modes in fuel cell electrodes. Comparative tomography data sets are acquired for a conditioned beginning of life (BOL) and a degraded end of life (EOL) membrane electrode assembly subjected to cathode degradation by voltage cycling. Micro length scale analysis shows a five-fold increase in crack size and 57% thickness reduction in the EOL cathode catalyst layer, indicating widespread action of carbon corrosion. Complementary nano length scale analysis shows a significant reduction in porosity, increased pore size, and dramatically reduced effective diffusivity within the remaining porous structure of the catalyst layer at EOL. Collapsing of the structure is evident from the combination of thinning and reduced porosity, as uniquely determined by the multi-length scale approach. Additionally, a novel image processing based technique developed for nano scale segregation of pore, ionomer, and Pt/C dominated voxels shows an increase in ionomer volume fraction, Pt/C agglomerates, and severe carbon corrosion at the catalyst layer/membrane interface at EOL. In summary, XCT based multi-length scale analysis enables detailed information needed for comprehensive understanding of the complex failure modes observed in fuel cell electrodes.

  18. Nuclear fuel cycle risk assessment: survey and computer compilation of risk-related literature. [Once-through Cycle and Plutonium Recycle

    SciTech Connect

    Yates, K.R.; Schreiber, A.M.; Rudolph, A.W.

    1982-10-01

    The US Nuclear Regulatory Commission has initiated the Fuel Cycle Risk Assessment Program to provide risk assessment methods for assistance in the regulatory process for nuclear fuel cycle facilities other than reactors. Both the once-through cycle and plutonium recycle are being considered. A previous report generated by this program defines and describes fuel cycle facilities, or elements, considered in the program. This report, the second from the program, describes the survey and computer compilation of fuel cycle risk-related literature. Sources of available information on the design, safety, and risk associated with the defined set of fuel cycle elements were searched and documents obtained were catalogued and characterized with respect to fuel cycle elements and specific risk/safety information. Both US and foreign surveys were conducted. Battelle's computer-based BASIS information management system was used to facilitate the establishment of the literature compilation. A complete listing of the literature compilation and several useful indexes are included. Future updates of the literature compilation will be published periodically. 760 annotated citations are included.

  19. Neutron analysis of spent fuel storage installation using parallel computing and advance discrete ordinates and Monte Carlo techniques.

    PubMed

    Shedlock, Daniel; Haghighat, Alireza

    2005-01-01

    In the United States, the Nuclear Waste Policy Act of 1982 mandated centralised storage of spent nuclear fuel by 1988. However, the Yucca Mountain project is currently scheduled to start accepting spent nuclear fuel in 2010. Since many nuclear power plants were only designed for -10 y of spent fuel pool storage, > 35 plants have been forced into alternate means of spent fuel storage. In order to continue operation and make room in spent fuel pools, nuclear generators are turning towards independent spent fuel storage installations (ISFSIs). Typical vertical concrete ISFSIs are -6.1 m high and 3.3 m in diameter. The inherently large system, and the presence of thick concrete shields result in difficulties for both Monte Carlo (MC) and discrete ordinates (SN) calculations. MC calculations require significant variance reduction and multiple runs to obtain a detailed dose distribution. SN models need a large number of spatial meshes to accurately model the geometry and high quadrature orders to reduce ray effects, therefore, requiring significant amounts of computer memory and time. The use of various differencing schemes is needed to account for radial heterogeneity in material cross sections and densities. Two P3, S12, discrete ordinate, PENTRAN (parallel environment neutral-particle TRANsport) models were analysed and different MC models compared. A multigroup MCNP model was developed for direct comparison to the SN models. The biased A3MCNP (automated adjoint accelerated MCNP) and unbiased (MCNP) continuous energy MC models were developed to assess the adequacy of the CASK multigroup (22 neutron, 18 gamma) cross sections. The PENTRAN SN results are in close agreement (5%) with the multigroup MC results; however, they differ by -20-30% from the continuous-energy MC predictions. This large difference can be attributed to the expected difference between multigroup and continuous energy cross sections, and the fact that the CASK library is based on the old ENDF

  20. Computational study of forced air-convection in open-cathode polymer electrolyte fuel cell stacks

    NASA Astrophysics Data System (ADS)

    Sasmito, A. P.; Lum, K. W.; Birgersson, E.; Mujumdar, A. S.

    A mathematical model for a polymer electrolyte fuel cell (PEFC) stack with an open-cathode manifold, where a fan provides the oxidant as well as cooling, is derived and studied. In short, the model considers two-phase flow and conservation of mass, momentum, species and energy in the ambient and PEFC stack, as well as conservation of charge and a phenomenological membrane and agglomerate model for the PEFC stack. The fan is resolved as an interfacial condition with a polynomial expression for the static pressure increase over the fan as a function of the fan velocity. The results suggest that there is strong correlation between fan power rating, the height of cathode flow-field and stack performance. Further, the placement of the fan - either in blowing or suction mode - does not give rise to a discernable difference in stack performance for the flow-field considered (metal mesh). Finally, it is noted that the model can be extended to incorporate other types of flow-fields and, most importantly, be employed for design and optimization of forced air-convection open-cathode PEFC stacks and adjacent fans.

  1. Computation of initial stage of RBMK reactor fuel channel vessel rupture

    SciTech Connect

    Pevnitsky, A.V.; Solovyev, V.P.; Abakumov, A.I.

    1995-12-31

    Objective of this work is estimation of temperature and time characteristics for rupture of the zirconium pipe which is the RBMK reactor fuel channel (FC) vessel under emergencies. As an emergency the zirconium pipe temperature rise process is considered which results in loss of pipe material strength properties and pipe rupture under the action of internal pressure P=80MPa. The work was carried out under Task Order 007 of University of California - VNIIEF Subcontract No. 0002P0004-95. The problem formulation is stated in Protocol (Task 3, Appendix 3) of the Russian-American Workshop which was held in December, 1994 in Los Alamos. Physical-mechanical and geometry characteristics of structure elements (FC vessel with graphite ring and graphite slug) are presented by NIKIET. The temperature mode of the structure is taken in conformity with the NIKIET data obtained with the RELAP5/MOD3 code. Numerical simulation of structure element behavior in an emergency is performed using the DRAKON program comlex oriented to solving strength problems for complex spatial structures at intense dynamic loading. The {open_quotes}DRAKON{close_quotes} program complex is described and compared with similar western codes in its capabilities.

  2. Computational simulation of thermal hydraulic processes in the model LMFBR fuel assembly

    NASA Astrophysics Data System (ADS)

    Bayaskhalanov, M. V.; Merinov, I. G.; Korsun, A. S.; Vlasov, M. N.

    2017-01-01

    The aim of this study was to verify a developed software module on the experimental fuel assembly with partial blockage of the flow section. The developed software module for simulation of thermal hydraulic processes in liquid metal coolant is based on theory of anisotropic porous media with specially developed integral turbulence model for coefficients determination. The finite element method is used for numerical solution. Experimental data for hexahedral assembly with electrically heated smooth cylindrical rods cooled by liquid sodium are considered. The results of calculation obtained with developed software module for a case of corner blockade are presented. The calculated distribution of coolant velocities showed the presence of the vortex flow behind the blockade. Features vortex region are in a good quantitative and qualitative agreement with experimental data. This demonstrates the efficiency of the hydrodynamic unit for developed software module. But obtained radial coolant temperature profiles differ significantly from the experimental in the vortex flow region. The possible reasons for this discrepancy were analyzed.

  3. SAS2H input for computing core activities of 4.5, 5.0, and 5.5 weight % {sup 235}U fuel for Sequoyah Nuclear Plant

    SciTech Connect

    Hermann, O.W.

    1994-08-01

    Sequoyah Nuclear Plant core activities at initial fuel enrichments of 4.5, 5.0, and 5.5 wt% {sup 235}U, required in nuclear safety evaluations, were computed by the SAS2H analysis sequence and the ORIGEN-S code within the SCALE-4.2 code system.

  4. Fossil fuel power plants: Computer systems for power plant control, maintenance, and operation. (Latest citations from the Compendex database). Published Search

    SciTech Connect

    Not Available

    1993-07-01

    The bibliography contains citations concerning fossil fuel power plant computer systems. Minicomputer and microcomputer systems used for monitoring, process control, performance calculations, alarming, and administrative applications are discussed. Topics emphasize power plant control, maintenance and operation. (Contains 250 citations and includes a subject term index and title list.)

  5. A Computational and Experimental Study of Coflow Laminar Methane/Air Diffusion Flames: Effects of Fuel Dilution, Inlet Velocity, and Gravity

    NASA Technical Reports Server (NTRS)

    Cao, S.; Ma, B.; Bennett, B. A. V.; Giassi, D.; Stocker, D. P.; Takahashi, F.; Long, M. B.; Smooke, M. D.

    2014-01-01

    The influences of fuel dilution, inlet velocity, and gravity on the shape and structure of laminar coflow CH4-air diffusion flames were investigated computationally and experimentally. A series of nitrogen-diluted flames measured in the Structure and Liftoff in Combustion Experiment (SLICE) on board the International Space Station was assessed numerically under microgravity (mu g) and normal gravity (1g) conditions with CH4 mole fraction ranging from 0.4 to 1.0 and average inlet velocity ranging from 23 to 90 cm/s. Computationally, the MC-Smooth vorticity-velocity formulation was employed to describe the reactive gaseous mixture, and soot evolution was modeled by sectional aerosol equations. The governing equations and boundary conditions were discretized on a two-dimensional computational domain by finite differences, and the resulting set of fully coupled, strongly nonlinear equations was solved simultaneously at all points using a damped, modified Newton's method. Experimentally, flame shape and soot temperature were determined by flame emission images recorded by a digital color camera. Very good agreement between computation and measurement was obtained, and the conclusions were as follows. (1) Buoyant and nonbuoyant luminous flame lengths are proportional to the mass flow rate of the fuel mixture; computed and measured nonbuoyant flames are noticeably longer than their 1g counterparts; the effect of fuel dilution on flame shape (i.e., flame length and flame radius) is negligible when the flame shape is normalized by the methane flow rate. (2) Buoyancy-induced reduction of the flame radius through radially inward convection near the flame front is demonstrated. (3) Buoyant and nonbuoyant flame structure is mainly controlled by the fuel mass flow rate, and the effects from fuel dilution and inlet velocity are secondary.

  6. OptFuels: Fuel treatment optimization

    Treesearch

    Greg Jones

    2011-01-01

    Scientists at the USDA Forest Service, Rocky Mountain Research Station, in Missoula, MT, in collaboration with scientists at the University of Montana, are developing a tool to help forest managers prioritize forest fuel reduction treatments. Although several computer models analyze fuels and fire behavior, stand-level effects of fuel treatments, and priority planning...

  7. Bureaucrats and Brainpower: Government Regulation of Universities.

    ERIC Educational Resources Information Center

    Seabury, Paul, Ed.

    The exploration of the growth and cost benefit effectiveness of governmental regulation of higher education is examined in this book. An introductory article by Robert Hatfield examines university regulation from a businessman's perspective. Hatfield concludes that business and higher education must work together to curb the stream of regulation.…

  8. Fuel flexible fuel injector

    DOEpatents

    Tuthill, Richard S; Davis, Dustin W; Dai, Zhongtao

    2015-02-03

    A disclosed fuel injector provides mixing of fuel with airflow by surrounding a swirled fuel flow with first and second swirled airflows that ensures mixing prior to or upon entering the combustion chamber. Fuel tubes produce a central fuel flow along with a central airflow through a plurality of openings to generate the high velocity fuel/air mixture along the axis of the fuel injector in addition to the swirled fuel/air mixture.

  9. Advanced computational tools for PEM fuel cell design. Part 2. Detailed experimental validation and parametric study

    NASA Astrophysics Data System (ADS)

    Sui, P. C.; Kumar, S.; Djilali, N.

    This paper reports on the systematic experimental validation of a comprehensive 3D CFD-based computational model presented and documented in Part 1. Simulations for unit cells with straight channels, similar to the Ballard Mk902 hardware, are performed and analyzed in conjunction with detailed current mapping measurements and water mass distributions in the membrane-electrode assembly. The experiments were designed to display sensitivity of the cell over a range of operating parameters including current density, humidification, and coolant temperature, making the data particularly well suited for systematic validation. Based on the validation and analysis of the predictions, values of model parameters, including the electro-osmotic drag coefficient, capillary diffusion coefficient, and catalyst specific surface area are determined adjusted to fit experimental data of current density and MEA water content. The predicted net water flux out of the anode (normalized by the total water generated) increases as anode humidification water flow rate is increased, in agreement with experimental results. A modification of the constitutive equation for the capillary diffusivity of water in the porous electrodes that attempts to incorporate the experimentally observed immobile (or irreducible) saturation yields a better fit of the predicted MEA water mass with experimental data. The specific surface area parameter used in the catalyst layer model is found to be effective in tuning the simulations to predict the correct cell voltage over a range of stoichiometries.

  10. Predicting chemical kinetics with computational chemistry: is QOO&(H)rarr;HOQO important in fuel ignition?

    NASA Astrophysics Data System (ADS)

    Green, William H.; Wijaya, Catherina D.; Yelvington, Paul E.; Sumathi, R.

    An overview of predictive chemical kinetics is presented, with an application to the simulation and design of homogeneous charge compression ignition (HCCI) engines. The engine simulations are sensitive to the details of hydroperoxyalkyl (QOOH) radical chemistry, which are only partially understood, and there is a significant discrepancy between the simulations and experiment that limits the usefulness of the simulations. One possible explanation is that QOOH decomposes by other channels not considered in existing combustion chemistry models. Rate constants for one of these neglected channels, the intramolecular radical attack on the QOOH peroxide linkage to form hydroxyalkoxyl (HOQO) radicals, are predicted using quantum chemistry (CBS-QB3), to test whether or not this proposed channel can explain the observed discrepancies in the engine simulations. Although this channel has a significant rate, the competing attack on the other O atom in the peroxide to form a cyclic ether+OH is computed to be an order of magnitude faster, so the HOQO channel does not appear to be fast enough to explain the discrepancy. Definitive judgement on the importance of this reaction channel will require a careful reconsideration of all the coupled chemically activated QOOH reaction channels using modern predictive chemical kinetics software.

  11. Model-based diagnosis through Structural Analysis and Causal Computation for automotive Polymer Electrolyte Membrane Fuel Cell systems

    NASA Astrophysics Data System (ADS)

    Polverino, Pierpaolo; Frisk, Erik; Jung, Daniel; Krysander, Mattias; Pianese, Cesare

    2017-07-01

    The present paper proposes an advanced approach for Polymer Electrolyte Membrane Fuel Cell (PEMFC) systems fault detection and isolation through a model-based diagnostic algorithm. The considered algorithm is developed upon a lumped parameter model simulating a whole PEMFC system oriented towards automotive applications. This model is inspired by other models available in the literature, with further attention to stack thermal dynamics and water management. The developed model is analysed by means of Structural Analysis, to identify the correlations among involved physical variables, defined equations and a set of faults which may occur in the system (related to both auxiliary components malfunctions and stack degradation phenomena). Residual generators are designed by means of Causal Computation analysis and the maximum theoretical fault isolability, achievable with a minimal number of installed sensors, is investigated. The achieved results proved the capability of the algorithm to theoretically detect and isolate almost all faults with the only use of stack voltage and temperature sensors, with significant advantages from an industrial point of view. The effective fault isolability is proved through fault simulations at a specific fault magnitude with an advanced residual evaluation technique, to consider quantitative residual deviations from normal conditions and achieve univocal fault isolation.

  12. Computational investigation of the flow field contribution to improve electricity generation in granular activated carbon-assisted microbial fuel cells

    NASA Astrophysics Data System (ADS)

    Zhao, Lei; Li, Jian; Battaglia, Francine; He, Zhen

    2016-11-01

    Microbial fuel cells (MFCs) offer an alternative approach to treat wastewater with less energy input and direct electricity generation. To optimize MFC anodic performance, adding granular activated carbon (GAC) has been proved to be an effective way, most likely due to the enlarged electrode surface for biomass attachment and improved mixing of the flow field. The impact of a flow field on the current enhancement within a porous anode medium (e.g., GAC) has not been well understood before, and thus is investigated in this study by using mathematical modeling of the multi-order Butler-Volmer equation with computational fluid dynamics (CFD) techniques. By comparing three different CFD cases (without GAC, with GAC as a nonreactive porous medium, and with GAC as a reactive porous medium), it is demonstrated that adding GAC contributes to a uniform flow field and a total current enhancement of 17%, a factor that cannot be neglected in MFC design. However, in an actual MFC operation, this percentage could be even higher because of the microbial competition and energy loss issues within a porous medium. The results of the present study are expected to help with formulating strategies to optimize MFC with a better flow pattern design.

  13. Computational analysis of a three-dimensional High-Velocity Oxygen-Fuel (HVOF) Thermal Spray torch

    SciTech Connect

    Hassan, B.; Lopez, A.R.; Oberkampf, W.L.

    1995-07-01

    An analysis of a High-Velocity Oxygen-Fuel Thermal Spray torch is presented using computational fluid dynamics (CFD). Three-dimensional CFD results are presented for a curved aircap used for coating interior surfaces such as engine cylinder bores. The device analyzed is similar to the Metco Diamond Jet Rotating Wire torch, but wire feed is not simulated. To the authors` knowledge, these are the first published 3-D results of a thermal spray device. The feed gases are injected through an axisymmetric nozzle into the curved aircap. Argon is injected through the center of the nozzle. Pre-mixed propylene and oxygen are introduced from an annulus in the nozzle, while cooling air is injected between the nozzle and the interior wall of the aircap. The combustion process is modeled assuming instantaneous chemistry. A standard, two-equation, K-{var_epsilon} turbulence model is employed for the turbulent flow field. An implicit, iterative, finite volume numerical technique is used to solve the coupled conservation of mass, momentum, and energy equations for the gas in a sequential manner. Flow fields inside and outside the aircap are presented and discussed.

  14. Computer-assisted school bus routing and scheduling optimization. An evaluation of potential fuel savings and implementation alternatives

    SciTech Connect

    McCoy, G.A.; Mandlebaum, R.

    1985-11-01

    School Bus Routing and Scheduling Optimization (SBRSO) systems can substantially reduce school bus fleet operating costs. Fuel savings in excess of 450,000 gallons per year are achievable and a 10% decrease in route miles is attainable given computerized or computer-assisted SBRSO system use by the 32 Washington school districts operating bus fleets of at least 30 vehicles. Additional annual savings in excess of $3 million are possible assuming an 8% reduction in bus fleet size is made possible due to routing efficiency improvements. Three computerized SBRSO programs are examined, differing in the degree of state involvement and level of decentralization. We recommend the Washington State Energy Office (WSEO) acquire available low cost public domain SBRSO systems, convert the software to IBM and DEC compatibility, and demonstrate the software capabilities with at least one school district fleet. The most acceptable SBRSO system would then be disseminated and training offered to interested school districts, Educational Service Districts, and the Superintendent of Public Instruction's regional pupil transportation coordinators. If the existing public domain SBRSO systems prove unsatisfactory, or suitable only for rural districts, we recommend that the WSEO allocate oil company rebate monies for the development of a suitable SBRSO system. Training workshops would then be held when the SBRSO software was completed.

  15. Investigation of the flow field inside the manifold of a real operated fuel cell stack using optical measurements and Computational Fluid Mechanics

    NASA Astrophysics Data System (ADS)

    Schmieder, Felix; Kinaci, Mustafa E.; Wartmann, Jens; König, Jörg; Büttner, Lars; Czarske, Jürgen; Burgmann, Sebastian; Heinzel, Angelika

    2016-02-01

    The versatility of fuel cells enables a wide range of applications. Usually fuel cells are combined to stacks such that the reactant supply of the single cells is achieved via a pipe branching system, the manifold. The overall performance significantly depends on cell flow rates which are related to the fluidic interaction of the manifold and the cells. Computational Fluid Dynamics (CFD) simulations, which are often used to find a suitable design, lack experimental flow data for validation of the numerical results. To enable flow measurements within the small geometries of the manifold and to provide reliable velocity information inside a real fuel cell stack, a low-coherence Laser Doppler Anemometer (LDA) is applied, which uses multi-mode laser light to achieve a spatial resolution of <100 μm. The use of fluorescent particles and backward scatter mode make the sensor highly suitable for the application in small manifold geometries like in fuel cell stacks. Sensor and measurement technique are validated in simplified stack models and the applicability to air flows is demonstrated. Finally, for the first time, velocity profiles with high spatial resolution inside an operated fuel cell stack are presented, which serve as benchmark for CFD to find an optimal geometry.

  16. An analysis of nuclear fuel burnup in the AGR-1 TRISO fuel experiment using gamma spectrometry, mass spectrometry, and computational simulation techniques

    SciTech Connect

    Harp, Jason M.; Demkowicz, Paul A.; Winston, Philip L.; Sterbentz, James W.

    2014-09-03

    AGR 1 was the first in a series of experiments designed to test US TRISO fuel under high temperature gas-cooled reactor irradiation conditions. This experiment was irradiated in the Advanced Test Reactor (ATR) at Idaho National Laboratory (INL) and is currently undergoing post irradiation examination (PIE) at INL and Oak Ridge National Laboratory. One component of the AGR 1 PIE is the experimental evaluation of the burnup of the fuel by two separate techniques. Gamma spectrometry was used to non destructively evaluate the burnup of all 72 of the TRISO fuel compacts that comprised the AGR 1 experiment. Two methods for evaluating burnup by gamma spectrometry were developed, one based on the Cs 137 activity and the other based on the ratio of Cs 134 and Cs 137 activities. Burnup values determined from both methods compared well with the values predicted from simulations. The highest measured burnup was 20.1% FIMA for the direct method and 20.0% FIMA for the ratio method (compared to 19.56% FIMA from simulations). An advantage of the ratio method is that the burnup of the cylindrical fuel compacts can determined in small (2.5 mm) axial increments and an axial burnup profile can be produced. Destructive chemical analysis by inductively coupled mass spectrometry (ICP MS) was then performed on selected compacts that were representative of the expected range of fuel burnups in the experiment to compare with the burnup values determined by gamma spectrometry. The compacts analyzed by mass spectrometry had a burnup range of 19.3% FIMA to 10.7% FIMA. The mass spectrometry evaluation of burnup for the four compacts agreed well with the gamma spectrometry burnup evaluations and the expected burnup from simulation. For all four compacts analyzed by mass spectrometry, the maximum range in the three experimentally determined values and the predicted value was 6% or less. Furthermore, the results confirm the accuracy of the nondestructive burnup evaluation from gamma spectrometry

  17. An analysis of nuclear fuel burnup in the AGR-1 TRISO fuel experiment using gamma spectrometry, mass spectrometry, and computational simulation techniques

    DOE PAGES

    Harp, Jason M.; Demkowicz, Paul A.; Winston, Philip L.; ...

    2014-09-03

    AGR 1 was the first in a series of experiments designed to test US TRISO fuel under high temperature gas-cooled reactor irradiation conditions. This experiment was irradiated in the Advanced Test Reactor (ATR) at Idaho National Laboratory (INL) and is currently undergoing post irradiation examination (PIE) at INL and Oak Ridge National Laboratory. One component of the AGR 1 PIE is the experimental evaluation of the burnup of the fuel by two separate techniques. Gamma spectrometry was used to non destructively evaluate the burnup of all 72 of the TRISO fuel compacts that comprised the AGR 1 experiment. Two methodsmore » for evaluating burnup by gamma spectrometry were developed, one based on the Cs 137 activity and the other based on the ratio of Cs 134 and Cs 137 activities. Burnup values determined from both methods compared well with the values predicted from simulations. The highest measured burnup was 20.1% FIMA for the direct method and 20.0% FIMA for the ratio method (compared to 19.56% FIMA from simulations). An advantage of the ratio method is that the burnup of the cylindrical fuel compacts can determined in small (2.5 mm) axial increments and an axial burnup profile can be produced. Destructive chemical analysis by inductively coupled mass spectrometry (ICP MS) was then performed on selected compacts that were representative of the expected range of fuel burnups in the experiment to compare with the burnup values determined by gamma spectrometry. The compacts analyzed by mass spectrometry had a burnup range of 19.3% FIMA to 10.7% FIMA. The mass spectrometry evaluation of burnup for the four compacts agreed well with the gamma spectrometry burnup evaluations and the expected burnup from simulation. For all four compacts analyzed by mass spectrometry, the maximum range in the three experimentally determined values and the predicted value was 6% or less. Furthermore, the results confirm the accuracy of the nondestructive burnup evaluation from gamma

  18. The DART dispersion analysis research tool: A mechanistic model for predicting fission-product-induced swelling of aluminum dispersion fuels. User`s guide for mainframe, workstation, and personal computer applications

    SciTech Connect

    Rest, J.

    1995-08-01

    This report describes the primary physical models that form the basis of the DART mechanistic computer model for calculating fission-product-induced swelling of aluminum dispersion fuels; the calculated results are compared with test data. In addition, DART calculates irradiation-induced changes in the thermal conductivity of the dispersion fuel, as well as fuel restructuring due to aluminum fuel reaction, amorphization, and recrystallization. Input instructions for execution on mainframe, workstation, and personal computers are provided, as is a description of DART output. The theory of fission gas behavior and its effect on fuel swelling is discussed. The behavior of these fission products in both crystalline and amorphous fuel and in the presence of irradiation-induced recrystallization and crystalline-to-amorphous-phase change phenomena is presented, as are models for these irradiation-induced processes.

  19. Some computations in planning reconstitution of a 500-MW(electric) fast breeder reactor (metallic) fuel by electrorefining

    SciTech Connect

    Nawada, H.P.; Bhat, N.P.; Balasubramanian, G.R.

    1996-04-01

    To compare and evaluate various fuel cycle options for a 500-MW(electric) fast breeder reactor, the electrorefining process has been examined for reprocessing spent fuel. Making use of an improved thermochemical model, optimum process conditions for electrorefining have been worked out. These conditions are the following: capacity of the electrorefining cell, number of cells, batch size, feed adjustments, sequential operations for recovery of uranium and co-recovery of uranium and plutonium, number of cycles, and time frame to meet the refueling schedule. The spent fuel is envisaged to undergo reprocessing in three campaigns: (a) the inner core campaign, (b) the outer core campaign, and (c) the blanket and the leftover campaign. Feed adjustments are done by mixing either the spent inner core or the outer core fuels with the blankets. Three product streams with required fuel composition for direct refabrication of the inner core, the outer core, and the blanket fuel subassemblies, respectively, are obtained by certain sequential electrorefiing operations. These calculations made for a mixed-oxide fuel core can be easily extended to the metallic core.

  20. Development of coupled SCALE4.2/GTRAN2 computational capability for advanced MOX fueled assembly designs

    SciTech Connect

    Vujic, J.; Greenspan, E.; Slater, Postma, T.; Casher, G.; Soares, I.; Leal, L.

    1995-05-01

    An advanced assembly code system that can efficiently and accurately analyze various designs (current and advanced) proposed for plutonium disposition is being developed by {open_quotes}marrying{close_quotes} two existing state-of-the-art methodologies-GTRAN2 and SCALE 4.2. The resulting code system, GT-SCALE, posses several unique characteristics: exact 2D representation of a complete fuel assembly, while preserving the heterogeniety of each of its pin cells; flexibility in the energy group structure, the present upper limit being 218 groups; a comprehensive cross-section library and material data base; and accurate burnup calculations. The resulting GT-SCALE is expected to be very useful for a wide variety of applications, including the analysis of very heterogeneous UO{sub 2} fueled LWR fuel assemblies; of hexagonal shaped fuel assemblies as of the Russian LWRs; of fuel assemblies for HTGRs; as well as for the analysis of criticality safety and for calculation of the source term of spent fuel.

  1. Computational sensitivity study of spray dispersion and mixing on the fuel properties in a gas turbine combustor

    NASA Astrophysics Data System (ADS)

    Grosshans, Holger; Cao, Le; Fuchs, Laszlo; Szász, Robert-Zoltán

    2017-04-01

    A swirl stabilized gas turbine burner has been simulated in order to assess the effects of the fuel properties on spray dispersion and fuel-air mixing. The properties under consideration include fuel surface tension, viscosity and density. The turbulence of the gas phase is modeled applying the methodology of large eddy simulation whereas the dispersed liquid phase is described by Lagrangian particle tracking. The exchange of mass, momentum and energy between the two phases is accounted for by two-way coupling. Bag and stripping breakup regimes are considered for secondary droplet breakup, using the Reitz-Diwakar and the Taylor analogy breakup models. Moreover, a model for droplet evaporation is included. The results reveal a high sensitivity of the spray structure to variations of all investigated parameters. In particular, a decrease in the surface tension or the fuel viscosity, or an increase in the fuel density, lead to less stable liquid structures. As a consequence, smaller droplets are generated and the overall spray surface area increases, leading to faster evaporation and mixing. Furthermore, with the trajectories of the small droplets being strongly influenced by aerodynamic forces (and less by their own inertia), the spray is more affected by the turbulent structures of the gaseous phase and the spray dispersion is enhanced.

  2. OPTIM: Computer program to generate a vertical profile which minimizes aircraft fuel burn or direct operating cost. User's guide

    NASA Technical Reports Server (NTRS)

    1983-01-01

    A profile of altitude, airspeed, and flight path angle as a function of range between a given set of origin and destination points for particular models of transport aircraft provided by NASA is generated. Inputs to the program include the vertical wind profile, the aircraft takeoff weight, the costs of time and fuel, certain constraint parameters and control flags. The profile can be near optimum in the sense of minimizing: (1) fuel, (2) time, or (3) a combination of fuel and time (direct operating cost (DOC)). The user can also, as an option, specify the length of time the flight is to span. The theory behind the technical details of this program is also presented.

  3. Description of the computations and pilot procedures for planning fuel-conservative descents with a small programmable calculator

    SciTech Connect

    Vicroy, D.D.; Knox, C.E.

    1983-05-01

    A simplified flight management descent algorithm was developed and programmed on a small programmable calculator. It was designed to aid the pilot in planning and executing a fuel conservative descent to arrive at a metering fix at a time designated by the air traffic control system. The algorithm may also be used for planning fuel conservative descents when time is not a consideration. The descent path was calculated for a constant Mach/airspeed schedule from linear approximations of airplane performance with considerations given for gross weight, wind, and nonstandard temperature effects. The flight management descent algorithm and the vertical performance modeling required for the DC-10 airplane is described.

  4. Description of the computations and pilot procedures for planning fuel-conservative descents with a small programmable calculator

    NASA Technical Reports Server (NTRS)

    Vicroy, D. D.; Knox, C. E.

    1983-01-01

    A simplified flight management descent algorithm was developed and programmed on a small programmable calculator. It was designed to aid the pilot in planning and executing a fuel conservative descent to arrive at a metering fix at a time designated by the air traffic control system. The algorithm may also be used for planning fuel conservative descents when time is not a consideration. The descent path was calculated for a constant Mach/airspeed schedule from linear approximations of airplane performance with considerations given for gross weight, wind, and nonstandard temperature effects. The flight management descent algorithm and the vertical performance modeling required for the DC-10 airplane is described.

  5. Computer program for prediction of fuel consumption statistical data for an upper stage three-axes stabilized on-off control system

    NASA Technical Reports Server (NTRS)

    1982-01-01

    A FORTRAN coded computer program and method to predict the reaction control fuel consumption statistics for a three axis stabilized rocket vehicle upper stage is described. A Monte Carlo approach is used which is more efficient by using closed form estimates of impulses. The effects of rocket motor thrust misalignment, static unbalance, aerodynamic disturbances, and deviations in trajectory, mass properties and control system characteristics are included. This routine can be applied to many types of on-off reaction controlled vehicles. The pseudorandom number generation and statistical analyses subroutines including the output histograms can be used for other Monte Carlo analyses problems.

  6. Validation of standardized computer analyses for licensing evaluation/TRITON two-dimensional and three-dimensional models for light water reactor fuel

    SciTech Connect

    Bowman, S. M.; Gill, D. F.

    2006-07-01

    The isotopic depletion capabilities of the new Standardized Computer Analyses for Licensing Evaluation control module TRITON, coupled with ORIGEN-S, were evaluated using spent fuel assays from several commercial light water reactors with both standard and mixed-oxide fuel assemblies. Calculations were performed using the functional modules NEWT and KENO-VI. NEWT is a two-dimensional, arbitrary-geometry, discrete-ordinates transport code, and KENO-VI is a three-dimensional Monte Carlo transport code capable of handling complex three-dimensional geometries. To validate the codes and data used in depletion calculations, numerical predictions were compared with experimental measurements for a total of 29 samples taken from the Calvert Cliffs, Obrigheim, and San Onofre pressurized water reactors and the Gundremmingen boiling water reactor. Similar comparisons have previously been performed at the Oak Ridge National Laboratory for the one-dimensional SAS2H control module. The SAS2H, TRITON/KENO-VI, and TRITON/NEWT results were compared for corresponding samples. All analyses showed that TRITON/KENO-VI and TRITON/NEWT produced typically similar or better results than SAS2H. The calculations performed in this validation study demonstrate that the depletion capabilities of TRITON accurately model spent fuel depletion and decay. (authors)

  7. Fueling systems

    SciTech Connect

    Gorker, G.E.

    1987-01-01

    This report deals with concepts of the Tiber II tokamak reactor fueling systems. Contained in this report are the fuel injection requirement data, startup fueling requirements, intermediate range fueling requirements, power range fueling requirements and research and development considerations. (LSR)

  8. Vehicle Design Evaluation Program (VDEP). A computer program for weight sizing, economic, performance and mission analysis of fuel-conservative aircraft, multibodied aircraft and large cargo aircraft using both JP and alternative fuels

    NASA Technical Reports Server (NTRS)

    Oman, B. H.

    1977-01-01

    The NASA Langley Research Center vehicle design evaluation program (VDEP-2) was expanded by (1) incorporating into the program a capability to conduct preliminary design studies on subsonic commercial transport type aircraft using both JP and such alternate fuels as hydrogen and methane;(2) incorporating an aircraft detailed mission and performance analysis capability; and (3) developing and incorporating an external loads analysis capability. The resulting computer program (VDEP-3) provides a preliminary design tool that enables the user to perform integrated sizing, structural analysis, and cost studies on subsonic commercial transport aircraft. Both versions of the VDEP-3 Program which are designated preliminary Analysis VDEP-3 and detailed Analysis VDEP utilize the same vehicle sizing subprogram which includes a detailed mission analysis capability, as well as a geometry and weight analysis for multibodied configurations.

  9. Field guide for identifying fuel loading models

    Treesearch

    Pamela G. Sikkink; Duncan C. Lutes; Robert E. Keane

    2009-01-01

    This report details a procedure for identifying fuel loading models (FLMs) in the field. FLMs are a new classification system for predicting fire effects from on-site fuels. Each FLM class represents fuel beds that have similar fuel loadings and produce similar emissions and soil surface heating when burned using computer simulations. We describe how to estimate fuel...

  10. The simulation of the alternate turbopump development high pressure oxygen and fuel turbopumps for the space shuttle main engine using the Shaberth computer program

    NASA Technical Reports Server (NTRS)

    Mcdonald, Gary H.

    1988-01-01

    The Space Shuttle Main Engine (SSME) is basically comprised of a combustion chamber and nozzle, high and low pressure oxygen turbopumps and high and low pressure fuel turbopumps. In the current configuration, the high pressure fuel (HPTFP) and high pressure oxygen turbopumps (HPOTP) have experienced a history of ball bearing wear. The wear problem can be attributed to numerous factors including the hydrodynamic axial and radial loads caused by the flow of liquid oxygen and liquid hydrogen through the turbopump impellers and turbine. Also, friction effects between the rolling elements, races, and cage can create thermally induced bearing geometry changes. To alleviate some of the current configuration problems, an alternate turbopump development (ATD) was proposed. However, the ATD HPOTP and HPTFP are constrained to operate interchangeably with the current turbopumps, thus, the operation conditions must be similar. The ATD configuration features a major change in bearings used to support the integrated shaft, impeller, and turbine system. A single ball and single roller will replace the pump-end and turbine and duplex ball bearings. The Shaft-Bearing-Thermal (SHABERTH) computer code was used to model the ATD HPOTP and ATD HPFTP configurations. A two bearing model was used to simulate the HPOTP and HPFTP bearings and shaft geometry. From SHABERTH, a comparison of bearing reaction loads, frictional heat generation rates, and Hertz contact stresses will be attempted with analysis at the 109 percent and 65 percent power levels.

  11. 4D in situ visualization of electrode morphology changes during accelerated degradation in fuel cells by X-ray computed tomography

    NASA Astrophysics Data System (ADS)

    White, Robin T.; Wu, Alex; Najm, Marina; Orfino, Francesco P.; Dutta, Monica; Kjeang, Erik

    2017-05-01

    A four-dimensional visualization approach, featuring three dimensions in space and one dimension in time, is proposed to study local electrode degradation effects during voltage cycling in fuel cells. Non-invasive in situ micro X-ray computed tomography (XCT) with a custom fuel cell fixture is utilized to track the same cathode catalyst layer domain throughout various degradation times from beginning-of-life (BOL) to end-of-life (EOL). With this unique approach, new information regarding damage features and trends are revealed, including crack propagation and catalyst layer thinning being quantified by means of image processing and analysis methods. Degradation heterogeneities as a result of local environmental variations under land and channel are also explored, with a higher structural degradation rate under channels being observed. Density and compositional changes resulting from carbon corrosion and catalyst layer collapse and thinning are observed by changes in relative X-ray attenuation from BOL to EOL, which also indicate possible vulnerable regions where crack initiation and propagation may occur. Electrochemical diagnostics and morphological features observed by micro-XCT are correlated by additionally collecting effective catalyst surface area, double layer capacitance, and polarization curves prior to imaging at various stages of degradation.

  12. Three-dimensional phase segregation of micro-porous layers for fuel cells by nano-scale X-ray computed tomography

    NASA Astrophysics Data System (ADS)

    Andisheh-Tadbir, Mehdi; Orfino, Francesco P.; Kjeang, Erik

    2016-04-01

    Modern hydrogen powered polymer electrolyte fuel cells (PEFCs) utilize a micro-porous layer (MPL) consisting of carbon nanoparticles and polytetrafluoroethylene (PTFE) to enhance the transport phenomena and performance while reducing cost. However, the underlying mechanisms are not yet completely understood due to a lack of information about the detailed MPL structure and properties. In the present work, the 3D phase segregated nanostructure of an MPL is revealed for the first time through the development of a customized, non-destructive procedure for monochromatic nano-scale X-ray computed tomography visualization. Utilizing this technique, it is discovered that PTFE is situated in conglomerated regions distributed randomly within connected domains of carbon particles; hence, it is concluded that PTFE acts as a binder for the carbon particles and provides structural support for the MPL. Exposed PTFE surfaces are also observed that will aid the desired hydrophobicity of the material. Additionally, the present approach uniquely enables phase segregated calculation of effective transport properties, as reported herein, which is particularly important for accurate estimation of electrical and thermal conductivity. Overall, the new imaging technique and associated findings may contribute to further performance improvements and cost reduction in support of fuel cell commercialization for clean energy applications.

  13. Fossil fuels -- future fuels

    SciTech Connect

    1998-03-01

    Fossil fuels -- coal, oil, and natural gas -- built America`s historic economic strength. Today, coal supplies more than 55% of the electricity, oil more than 97% of the transportation needs, and natural gas 24% of the primary energy used in the US. Even taking into account increased use of renewable fuels and vastly improved powerplant efficiencies, 90% of national energy needs will still be met by fossil fuels in 2020. If advanced technologies that boost efficiency and environmental performance can be successfully developed and deployed, the US can continue to depend upon its rich resources of fossil fuels.

  14. Graphics enhanced computer emulation for improved timing-race and fault tolerance control system analysis. [of Centaur liquid-fuel booster

    NASA Technical Reports Server (NTRS)

    Szatkowski, G. P.

    1983-01-01

    A computer simulation system has been developed for the Space Shuttle's advanced Centaur liquid fuel booster rocket, in order to conduct systems safety verification and flight operations training. This simulation utility is designed to analyze functional system behavior by integrating control avionics with mechanical and fluid elements, and is able to emulate any system operation, from simple relay logic to complex VLSI components, with wire-by-wire detail. A novel graphics data entry system offers a pseudo-wire wrap data base that can be easily updated. Visual subsystem operations can be selected and displayed in color on a six-monitor graphics processor. System timing and fault verification analyses are conducted by injecting component fault modes and min/max timing delays, and then observing system operation through a red line monitor.

  15. Graphics enhanced computer emulation for improved timing-race and fault tolerance control system analysis. [of Centaur liquid-fuel booster

    NASA Technical Reports Server (NTRS)

    Szatkowski, G. P.

    1983-01-01

    A computer simulation system has been developed for the Space Shuttle's advanced Centaur liquid fuel booster rocket, in order to conduct systems safety verification and flight operations training. This simulation utility is designed to analyze functional system behavior by integrating control avionics with mechanical and fluid elements, and is able to emulate any system operation, from simple relay logic to complex VLSI components, with wire-by-wire detail. A novel graphics data entry system offers a pseudo-wire wrap data base that can be easily updated. Visual subsystem operations can be selected and displayed in color on a six-monitor graphics processor. System timing and fault verification analyses are conducted by injecting component fault modes and min/max timing delays, and then observing system operation through a red line monitor.

  16. Inter-comparison of Computer Codes for TRISO-based Fuel Micro-Modeling and Performance Assessment

    SciTech Connect

    Brian Boer; Chang Keun Jo; Wen Wu; Abderrafi M. Ougouag; Donald McEachren; Francesco Venneri

    2010-10-01

    The Next Generation Nuclear Plant (NGNP), the Deep Burn Pebble Bed Reactor (DB-PBR) and the Deep Burn Prismatic Block Reactor (DB-PMR) are all based on fuels that use TRISO particles as their fundamental constituent. The TRISO particle properties include very high durability in radiation environments, hence the designs reliance on the TRISO to form the principal barrier to radioactive materials release. This durability forms the basis for the selection of this fuel type for applications such as Deep Bun (DB), which require exposures up to four times those expected for light water reactors. It follows that the study and prediction of the durability of TRISO particles must be carried as part of the safety and overall performance characterization of all the designs mentioned above. Such evaluations have been carried out independently by the performers of the DB project using independently developed codes. These codes, PASTA, PISA and COPA, incorporate models for stress analysis on the various layers of the TRISO particle (and of the intervening matrix material for some of them), model for fission products release and migration then accumulation within the SiC layer of the TRISO particle, just next to the layer, models for free oxygen and CO formation and migration to the same location, models for temperature field modeling within the various layers of the TRISO particle and models for the prediction of failure rates. All these models may be either internal to the code or external. This large number of models and the possibility of different constitutive data and model formulations and the possibility of a variety of solution techniques makes it highly unlikely that the model would give identical results in the modeling of identical situations. The purpose of this paper is to present the results of an inter-comparison between the codes and to identify areas of agreement and areas that need reconciliation. The inter-comparison has been carried out by the cooperating

  17. Development of simplified airborne computations for fuel conservative descents in a time-based metered air traffic environment

    NASA Technical Reports Server (NTRS)

    Knox, C. E.

    1981-01-01

    The NASA has developed and flight-tested a simple flight management descent algorithm designed to improve the accuracy of delivering an airplane in a fuel-conservative manner to a metering fix at a time designated by air traffic control. This algorithm provides a three-dimensional path with terminal area time constraints (four-dimensional) for an airplane to make an idle-thrust, clean-configured (landing gear up, flaps zero, and speed brakes retracted) descent to arrive at the metering fix at a predetermined time, altitude, and airspeed. The descent path is calculated for a constant Mach/airspeed schedule from linear approximations of airplane performance with considerations given for gross weight, wind, and nonstandard pressure and temperature effects. Applications of the four-dimensional and descent planning capabilities of the algorithm to conventional airplanes is being investigated. This report describes the flight management descent algorithm and presents the results of the flight tests flown with the Terminal Configured Vehicle airplane.

  18. Revisiting kinetic boundary conditions at the surface of fuel droplet hydrocarbons: An atomistic computational fluid dynamics simulation.

    PubMed

    Nasiri, Rasoul

    2016-05-24

    The role of boundary conditions at the interface for both Boltzmann equation and the set of Navier-Stokes equations have been suggested to be important for studying of multiphase flows such as evaporation/condensation process which doesn't always obey the equilibrium conditions. Here we present aspects of transition-state theory (TST) alongside with kinetic gas theory (KGT) relevant to the study of quasi-equilibrium interfacial phenomena and the equilibrium gas phase processes, respectively. A two-state mathematical model for long-chain hydrocarbons which have multi-structural specifications is introduced to clarify how kinetics and thermodynamics affect evaporation/condensation process at the surface of fuel droplet, liquid and gas phases and then show how experimental observations for a number of n-alkane may be reproduced using a hybrid framework TST and KGT with physically reasonable parameters controlling the interface, gas and liquid phases. The importance of internal activation dynamics at the surface of n-alkane droplets is established during the evaporation/condensation process.

  19. Revisiting kinetic boundary conditions at the surface of fuel droplet hydrocarbons: An atomistic computational fluid dynamics simulation

    PubMed Central

    Nasiri, Rasoul

    2016-01-01

    The role of boundary conditions at the interface for both Boltzmann equation and the set of Navier-Stokes equations have been suggested to be important for studying of multiphase flows such as evaporation/condensation process which doesn’t always obey the equilibrium conditions. Here we present aspects of transition-state theory (TST) alongside with kinetic gas theory (KGT) relevant to the study of quasi-equilibrium interfacial phenomena and the equilibrium gas phase processes, respectively. A two-state mathematical model for long-chain hydrocarbons which have multi-structural specifications is introduced to clarify how kinetics and thermodynamics affect evaporation/condensation process at the surface of fuel droplet, liquid and gas phases and then show how experimental observations for a number of n-alkane may be reproduced using a hybrid framework TST and KGT with physically reasonable parameters controlling the interface, gas and liquid phases. The importance of internal activation dynamics at the surface of n-alkane droplets is established during the evaporation/condensation process. PMID:27215897

  20. Revisiting kinetic boundary conditions at the surface of fuel droplet hydrocarbons: An atomistic computational fluid dynamics simulation

    NASA Astrophysics Data System (ADS)

    Nasiri, Rasoul

    2016-05-01

    The role of boundary conditions at the interface for both Boltzmann equation and the set of Navier-Stokes equations have been suggested to be important for studying of multiphase flows such as evaporation/condensation process which doesn’t always obey the equilibrium conditions. Here we present aspects of transition-state theory (TST) alongside with kinetic gas theory (KGT) relevant to the study of quasi-equilibrium interfacial phenomena and the equilibrium gas phase processes, respectively. A two-state mathematical model for long-chain hydrocarbons which have multi-structural specifications is introduced to clarify how kinetics and thermodynamics affect evaporation/condensation process at the surface of fuel droplet, liquid and gas phases and then show how experimental observations for a number of n-alkane may be reproduced using a hybrid framework TST and KGT with physically reasonable parameters controlling the interface, gas and liquid phases. The importance of internal activation dynamics at the surface of n-alkane droplets is established during the evaporation/condensation process.

  1. Development of simplified airborne computations for fuel conservative descents in a time-based metered air traffic environment

    NASA Technical Reports Server (NTRS)

    Knox, C. E.

    1981-01-01

    The NASA has developed and flight-tested a simple flight management descent algorithm designed to improve the accuracy of delivering an airplane in a fuel-conservative manner to a metering fix at a time designated by air traffic control. This algorithm provides a three-dimensional path with terminal area time constraints (four-dimensional) for an airplane to make an idle-thrust, clean-configured (landing gear up, flaps zero, and speed brakes retracted) descent to arrive at the metering fix at a predetermined time, altitude, and airspeed. The descent path is calculated for a constant Mach/airspeed schedule from linear approximations of airplane performance with considerations given for gross weight, wind, and nonstandard pressure and temperature effects. Applications of the four-dimensional and descent planning capabilities of the algorithm to conventional airplanes is being investigated. This report describes the flight management descent algorithm and presents the results of the flight tests flown with the Terminal Configured Vehicle airplane.

  2. Computational fluid dynamics analyses of lateral heat conduction, coolant azimuthal mixing and heat transfer predictions in a BR2 fuel assembly geometry.

    SciTech Connect

    Tzanos, C. P.; Dionne, B.

    2011-05-23

    To support the analyses related to the conversion of the BR2 core from highly-enriched (HEU) to low-enriched (LEU) fuel, the thermal-hydraulics codes PLTEMP and RELAP-3D are used to evaluate the safety margins during steady-state operation (PLTEMP), as well as after a loss-of-flow, loss-of-pressure, or a loss of coolant event (RELAP). In the 1-D PLTEMP and RELAP simulations, conduction in the azimuthal and axial directions is not accounted. The very good thermal conductivity of the cladding and the fuel meat and significant temperature gradients in the lateral directions (axial and azimuthal directions) could lead to a heat flux distribution that is significantly different than the power distribution. To evaluate the significance of the lateral heat conduction, 3-D computational fluid dynamics (CFD) simulations, using the CFD code STAR-CD, were performed. Safety margin calculations are typically performed for a hot stripe, i.e., an azimuthal region of the fuel plates/coolant channel containing the power peak. In a RELAP model, for example, a channel between two plates could be divided into a number of RELAP channels (stripes) in the azimuthal direction. In a PLTEMP model, the effect of azimuthal power peaking could be taken into account by using engineering factors. However, if the thermal mixing in the azimuthal direction of a coolant channel is significant, a stripping approach could be overly conservative by not taking into account this mixing. STAR-CD simulations were also performed to study the thermal mixing in the coolant. Section II of this document presents the results of the analyses of the lateral heat conduction and azimuthal thermal mixing in a coolant channel. Finally, PLTEMP and RELAP simulations rely on the use of correlations to determine heat transfer coefficients. Previous analyses showed that the Dittus-Boelter correlation gives significantly more conservative (lower) predictions than the correlations of Sieder-Tate and Petukhov. STAR-CD 3-D

  3. Alternative Fuels

    EPA Pesticide Factsheets

    Alternative fuels include gaseous fuels such as hydrogen, natural gas, and propane; alcohols such as ethanol, methanol, and butanol; vegetable and waste-derived oils; and electricity. Overview of alternative fuels is here.

  4. Fuel pin

    DOEpatents

    Christiansen, David W.; Karnesky, Richard A.; Leggett, Robert D.; Baker, Ronald B.

    1989-10-03

    A fuel pin for a liquid metal nuclear reactor is provided. The fuel pin includes a generally cylindrical cladding member with metallic fuel material disposed therein. At least a portion of the fuel material extends radially outwardly to the inner diameter of the cladding member to promote efficient transfer of heat to the reactor coolant system. The fuel material defines at least one void space therein to facilitate swelling of the fuel material during fission.

  5. Fuel pin

    DOEpatents

    Christiansen, David W.; Karnesky, Richard A.; Leggett, Robert D.; Baker, Ronald B.

    1989-01-01

    A fuel pin for a liquid metal nuclear reactor is provided. The fuel pin includes a generally cylindrical cladding member with metallic fuel material disposed therein. At least a portion of the fuel material extends radially outwardly to the inner diameter of the cladding member to promote efficient transfer of heat to the reactor coolant system. The fuel material defines at least one void space therein to facilitate swelling of the fuel material during fission.

  6. Fuel pin

    DOEpatents

    Christiansen, D.W.; Karnesky, R.A.; Leggett, R.D.; Baker, R.B.

    1987-11-24

    A fuel pin for a liquid metal nuclear reactor is provided. The fuel pin includes a generally cylindrical cladding member with metallic fuel material disposed therein. At least a portion of the fuel material extends radially outwardly to the inner diameter of the cladding member to promote efficient transfer of heat to the reactor coolant system. The fuel material defines at least one void space therein to facilitate swelling of the fuel material during fission.

  7. Fuel pin

    SciTech Connect

    Christiansen, D.W.; Karnesky, R.A.; Leggett, R.D.; Baker, R.B.

    1987-11-24

    A fuel pin for a liquid metal nuclear reactor is provided. The fuel pin includes a generally cylindrical cladding member with metallic fuel material disposed therein. At least a portion of the fuel material extends radially outwardly to the inner diameter of the cladding member to promote efficient transfer of heat to the reactor coolant system. The fuel material defines at least one void space therein to facilitate swelling of the fuel material during fission.

  8. Application of X-ray micro-computed tomography on high-speed cavitating diesel fuel flows

    NASA Astrophysics Data System (ADS)

    Mitroglou, N.; Lorenzi, M.; Santini, M.; Gavaises, M.

    2016-11-01

    The flow inside a purpose built enlarged single-orifice nozzle replica is quantified using time-averaged X-ray micro-computed tomography (micro-CT) and high-speed shadowgraphy. Results have been obtained at Reynolds and cavitation numbers similar to those of real-size injectors. Good agreement for the cavitation extent inside the orifice is found between the micro-CT and the corresponding temporal mean 2D cavitation image, as captured by the high-speed camera. However, the internal 3D structure of the developing cavitation cloud reveals a hollow vapour cloud ring formed at the hole entrance and extending only at the lower part of the hole due to the asymmetric flow entry. Moreover, the cavitation volume fraction exhibits a significant gradient along the orifice volume. The cavitation number and the needle valve lift seem to be the most influential operating parameters, while the Reynolds number seems to have only small effect for the range of values tested. Overall, the study demonstrates that use of micro-CT can be a reliable tool for cavitation in nozzle orifices operating under nominal steady-state conditions.

  9. Final report on LDRD project : elucidating performance of proton-exchange-membrane fuel cells via computational modeling with experimental discovery and validation.

    SciTech Connect

    Wang, Chao Yang (Pennsylvania State University, University Park, PA); Pasaogullari, Ugur (Pennsylvania State University, University Park, PA); Noble, David R.; Siegel, Nathan P.; Hickner, Michael A.; Chen, Ken Shuang

    2006-11-01

    In this report, we document the accomplishments in our Laboratory Directed Research and Development project in which we employed a technical approach of combining experiments with computational modeling and analyses to elucidate the performance of hydrogen-fed proton exchange membrane fuel cells (PEMFCs). In the first part of this report, we document our focused efforts on understanding water transport in and removal from a hydrogen-fed PEMFC. Using a transparent cell, we directly visualized the evolution and growth of liquid-water droplets at the gas diffusion layer (GDL)/gas flow channel (GFC) interface. We further carried out a detailed experimental study to observe, via direct visualization, the formation, growth, and instability of water droplets at the GDL/GFC interface using a specially-designed apparatus, which simulates the cathode operation of a PEMFC. We developed a simplified model, based on our experimental observation and data, for predicting the onset of water-droplet instability at the GDL/GFC interface. Using a state-of-the-art neutron imaging instrument available at NIST (National Institute of Standard and Technology), we probed liquid-water distribution inside an operating PEMFC under a variety of operating conditions and investigated effects of evaporation due to local heating by waste heat on water removal. Moreover, we developed computational models for analyzing the effects of micro-porous layer on net water transport across the membrane and GDL anisotropy on the temperature and water distributions in the cathode of a PEMFC. We further developed a two-phase model based on the multiphase mixture formulation for predicting the liquid saturation, pressure drop, and flow maldistribution across the PEMFC cathode channels. In the second part of this report, we document our efforts on modeling the electrochemical performance of PEMFCs. We developed a constitutive model for predicting proton conductivity in polymer electrolyte membranes and compared

  10. Resolving Heterogeneous 3D Microstructures in Commercial Solid Oxide Fuel Cells using Micro- and Nano-scale X-ray Computed Tomography

    DOE PAGES

    Epting, William K; Mansley, Zachary; Menasche, David B; ...

    2017-05-01

    The electrodes in solid oxide fuel cells (SOFCs) consist of three phases interconnected in three dimensions. The volume needed to describe quantitatively such microstructures depends on several lengths scales, which are functions of materials properties and fabrication methods. This work focuses on quantifying the volume needed to represent “intermediate frequency” heterogeneities in electrodes of a commercial SOFC using X-ray computed tomography (CT) over two different length scales. Electrode volumes of 150 x 150 x 9 μm3 were extracted from a synchrotron-based micro-CT data set, with 13 μm3 voxels. 13.6 x 19.8 x 19.4 μm3 of the cathode and 26.3 xmore » 24.8 x 15.7 μm3 of the anode were extracted from laboratory nano-CT data sets, both with 653 nm3 voxels. After comparing the variation across sub-regions for the greyscale values from the micro-CT, and for the phase fractions and triple phase boundary densities from the nano-CT, it was found that the sub-region length scales needed to yield statistically similar average values were an order of magnitude larger than those expected to capture the “high frequency” heterogeneity related to the discrete nature of the three phases in electrodes. The challenge of quantifying such electrodes using available experimental methods is discussed.« less

  11. Fuel pump

    SciTech Connect

    Bellis, P.D.; Nesselrode, F.

    1991-04-16

    This patent describes a fuel pump. It includes: a fuel reservoir member, the fuel reservoir member being formed with fuel chambers, the chambers comprising an inlet chamber and an outlet chamber, means to supply fuel to the inlet chamber, means to deliver fuel from the outlet chamber to a point of use, the fuel reservoir member chambers also including a bypass chamber, means interconnecting the bypass chamber with the outlet chamber; the fuel pump also comprising pump means interconnecting the inlet chamber and the outlet chamber and adapted to suck fuel from the fuel supply means into the inlet chamber, through the pump means, out the outlet chamber, and to the fuel delivery means; the bypass chamber and the pump means providing two substantially separate paths of fuel flow in the fuel reservoir member, bypass plunger means normally closing off the flow of fuel through the bypass chamber one of the substantially separate paths including the fuel supply means and the fuel delivery means when the bypass plunger means is closed, the second of the substantially separate paths including the bypass chamber when the bypass plunger means is open, and all of the chambers and the interconnecting means therebetween being configured so as to create turbulence in the flow of any fuel supplied to the outlet chamber by the pump means and bypassed through the bypass chamber and the interconnecting means.

  12. Stochastic modelling of power reactor fuel behavior

    NASA Astrophysics Data System (ADS)

    Mirza, Shahid Nawaz

    An understanding of the in-reactor behavior of nuclear fuel is essential to the safe and economic operation of a nuclear power plant. It is no longer possible to achieve this without computer code calculations. A state of art computer code, FRODO, for Fuel ROD Operation, has been developed to model the steady state behavior of fuel pins in a light water reactor and to do sensitivity analysis. FRODO concentrates on the thermal performance, fission product release and pellet-clad interaction and can be used to predict the fuel failure under the prevailing conditions. FRODO incorporates the numerous uncertainties involved in fuel behavior modeling, using statistical methods, to ascertain fuel failures and their causes. Sensitivity of fuel failure to different fuel parameters and reactor conditions can be easily evaluated. FRODO has been used to analyze the sensitivities of fuel failures to coolant flow reductions. It is found that the uncertainties have pronounced effects on conclusions about fuel failures and their causes.

  13. Combustion engineering issues for solid fuel systems

    SciTech Connect

    Bruce Miller; David Tillman

    2008-05-15

    The book combines modeling, policy/regulation and fuel properties with cutting edge breakthroughs in solid fuel combustion for electricity generation and industrial applications. This book provides real-life experiences and tips for addressing the various technical, operational and regulatory issues that are associated with the use of fuels. Contents are: Introduction; Coal Characteristics; Characteristics of Alternative Fuels; Characteristics and Behavior of Inorganic Constituents; Fuel Blending for Combustion Management; Fuel Preparation; Conventional Firing Systems; Fluidized-Bed Firing Systems; Post-Combustion Emissions Control; Some Computer Applications for Combustion Engineering with Solid Fuels; Gasification; Policy Considerations for Combustion Engineering.

  14. Multidimensional Fuel Performance Code: BISON

    SciTech Connect

    2014-09-03

    BISON is a finite element based nuclear fuel performance code applicable to a variety of fuel forms including light water reactor fuel rods, TRISO fuel particles, and metallic rod and plate fuel (Refs. [a, b, c]). It solves the fully-coupled equations of thermomechanics and species diffusion and includes important fuel physics such as fission gas release and material property degradation with burnup. BISON is based on the MOOSE framework (Ref. [d]) and can therefore efficiently solve problems on 1-, 2- or 3-D meshes using standard workstations or large high performance computers. BISON is also coupled to a MOOSE-based mesoscale phase field material property simulation capability (Refs. [e, f]). As described here, BISON includes the code library named FOX, which was developed concurrent with BISON. FOX contains material and behavioral models that are specific to oxide fuels.

  15. Synthetic Fuel

    SciTech Connect

    Idaho National Laboratory - Steve Herring, Jim O'Brien, Carl Stoots

    2008-03-26

    Two global energy priorities today are finding environmentally friendly alternatives to fossil fuels, and reducing greenhouse gass Two global energy priorities today are finding environmentally friendly alternatives to fossil fuels, and reducing greenhous

  16. Synthetic Fuel

    ScienceCinema

    Idaho National Laboratory - Steve Herring, Jim O'Brien, Carl Stoots

    2016-07-12

    Two global energy priorities today are finding environmentally friendly alternatives to fossil fuels, and reducing greenhouse gass Two global energy priorities today are finding environmentally friendly alternatives to fossil fuels, and reducing greenhous

  17. Fuel cells

    NASA Astrophysics Data System (ADS)

    1984-12-01

    The US Department of Energy (DOE), Office of Fossil Energy, has supported and managed a fuel cell research and development (R and D) program since 1976. Responsibility for implementing DOE's fuel cell program, which includes activities related to both fuel cells and fuel cell systems, has been assigned to the Morgantown Energy Technology Center (METC) in Morgantown, West Virginia. The total United States effort of the private and public sectors in developing fuel cell technology is referred to as the National Fuel Cell Program (NFCP). The goal of the NFCP is to develop fuel cell power plants for base-load and dispersed electric utility systems, industrial cogeneration, and on-site applications. To achieve this goal, the fuel cell developers, electric and gas utilities, research institutes, and Government agencies are working together. Four organized groups are coordinating the diversified activities of the NFCP. The status of the overall program is reviewed in detail.

  18. Future Fuels

    DTIC Science & Technology

    2005-10-04

    tactical ground mobility and increasing operational reach • Identify, review, and assess – Technologies for reducing fuel consumption, including...T I O N S A C T I O N S TOR Focus - Tactical ground mobility - Operational reach - Not A/C, Ships, or troops Hybrid Electric Vehicle Fuel Management...Fuel Management During Combat Operations Energy Fundamentals • Energy Density • Tactical Mobility • Petroleum Use • Fuel Usage (TWV) • TWV OP TEMPO TOR

  19. Alternative Fuels

    DTIC Science & Technology

    2009-06-11

    JP-8 BACK-UP SLIDES Unclassified 19 What Are Biofuels ? Cellulose “first generation”“second generation” C18:0 C16:1 Triglycerides (fats, oils ...equipment when supplying jet fuel not practicable or cost effective Unclassified 5 erna ve ue s ocus Petroleum Crude Oil (declining discovery / production...on Jet A/A-1 Approved fuels, DXXXX Unclassified 6 JP-8/5 (Commercial Jet Fuel, ASTM Spec) DARPA Alternative Jet Fuels • Agricultural crop oils

  20. Fossil Fuels.

    ERIC Educational Resources Information Center

    Crank, Ron

    This instructional unit is one of 10 developed by students on various energy-related areas that deals specifically with fossil fuels. Some topics covered are historic facts, development of fuels, history of oil production, current and future trends of the oil industry, refining fossil fuels, and environmental problems. Material in each unit may…

  1. Fossil Fuels.

    ERIC Educational Resources Information Center

    Crank, Ron

    This instructional unit is one of 10 developed by students on various energy-related areas that deals specifically with fossil fuels. Some topics covered are historic facts, development of fuels, history of oil production, current and future trends of the oil industry, refining fossil fuels, and environmental problems. Material in each unit may…

  2. Alternative fuels

    NASA Technical Reports Server (NTRS)

    Grobman, J. S.; Butze, H. F.; Friedman, R.; Antoine, A. C.; Reynolds, T. W.

    1977-01-01

    Potential problems related to the use of alternative aviation turbine fuels are discussed and both ongoing and required research into these fuels is described. This discussion is limited to aviation turbine fuels composed of liquid hydrocarbons. The advantages and disadvantages of the various solutions to the problems are summarized. The first solution is to continue to develop the necessary technology at the refinery to produce specification jet fuels regardless of the crude source. The second solution is to minimize energy consumption at the refinery and keep fuel costs down by relaxing specifications.

  3. Fuel compositions

    SciTech Connect

    Mekonen, K.

    1989-10-31

    This patent describes a hydrosol fuel. It comprises: from about 67% to 94% by weight of a hydrocarbon combustible fuel selected from the group consisting of the gasolines, diesel fuels and heavy fuel oils, from 5 to 25% by weight of water, at least one surfactant operable to create a hydrosol with the fuel and water present in the range of 0.1 up to about 3.4% by weight of an additive selected from the group consisting of alpha (mono) olefins and alkyl benzenes, each of the former having 7 to 15 recurring C{sub 2} monomers therein.

  4. Fields of Fuel

    ERIC Educational Resources Information Center

    Russ, Rosemary S.; Wangen, Steve; Nye, D. Leith; Shapiro, R. Benjamin; Strinz, Will; Ferris, Michael

    2015-01-01

    To help teachers engage students in discussions about sustainability, the authors designed Fields of Fuel, a multiplayer, web-based simulation game that allows players to explore the environmental and economic trade-offs of a realistic sustainable system. Computer-based simulations of real-world phenomena engage students and have been shown to…

  5. Fields of Fuel

    ERIC Educational Resources Information Center

    Russ, Rosemary S.; Wangen, Steve; Nye, D. Leith; Shapiro, R. Benjamin; Strinz, Will; Ferris, Michael

    2015-01-01

    To help teachers engage students in discussions about sustainability, the authors designed Fields of Fuel, a multiplayer, web-based simulation game that allows players to explore the environmental and economic trade-offs of a realistic sustainable system. Computer-based simulations of real-world phenomena engage students and have been shown to…

  6. Fuel Burn Estimation Using Real Track Data

    NASA Technical Reports Server (NTRS)

    Chatterji, Gano B.

    2011-01-01

    A procedure for estimating fuel burned based on actual flight track data, and drag and fuel-flow models is described. The procedure consists of estimating aircraft and wind states, lift, drag and thrust. Fuel-flow for jet aircraft is determined in terms of thrust, true airspeed and altitude as prescribed by the Base of Aircraft Data fuel-flow model. This paper provides a theoretical foundation for computing fuel-flow with most of the information derived from actual flight data. The procedure does not require an explicit model of thrust and calibrated airspeed/Mach profile which are typically needed for trajectory synthesis. To validate the fuel computation method, flight test data provided by the Federal Aviation Administration were processed. Results from this method show that fuel consumed can be estimated within 1% of the actual fuel consumed in the flight test. Next, fuel consumption was estimated with simplified lift and thrust models. Results show negligible difference with respect to the full model without simplifications. An iterative takeoff weight estimation procedure is described for estimating fuel consumption, when takeoff weight is unavailable, and for establishing fuel consumption uncertainty bounds. Finally, the suitability of using radar-based position information for fuel estimation is examined. It is shown that fuel usage could be estimated within 5.4% of the actual value using positions reported in the Airline Situation Display to Industry data with simplified models and iterative takeoff weight computation.

  7. Criticality of spent reactor fuel

    SciTech Connect

    Harris, D.R.

    1987-01-01

    The storage capacity of spent reactor fuel pools can be greatly increased by consolidation. In this process, the fuel rods are removed from reactor fuel assemblies and are stored in close-packed arrays in a canister or skeleton. An earlier study examined criticality consideration for consolidation of Westinghouse fuel, assumed to be fresh, in canisters at the Millstone-2 spent-fuel pool and in the General Electric IF-300 shipping cask. The conclusions were that the fuel rods in the canister are so deficient in water that they are adequately subcritical, both in normal and in off-normal conditions. One potential accident, the water spill event, remained unresolved in the earlier study. A methodology is developed here for spent-fuel criticality and is applied to the water spill event. The methodology utilizes LEOPARD to compute few-group cross sections for the diffusion code PDQ7, which then is used to compute reactivity. These codes give results for fresh fuel that are in good agreement with KENO IV-NITAWL Monte Carlo results, which themselves are in good agreement with continuous energy Monte Carlo calculations. These methodologies are in reasonable agreement with critical measurements for undepleted fuel.

  8. Recent metal fuel safety tests in TREAT

    SciTech Connect

    Wright, A.E.; Bauer, T.H.; Lo, R.K.; Robinson, W.R.; Palm, R.G.

    1986-01-01

    In-reactor safety tests have been performed on metal-alloy reactor fuel to study its response to transient-overpower conditions, in particular, the margin to cladding breach and the axial self-extrusion of fuel within intact cladding. Uranium-fissium EBR-II driver fuel elements of several burnups were tested, some to cladding breach and others to incipient breach. Transient fuel motions were monitored, and time and location of breach were measured. The test results and computations of fuel extrusion and cladding failure in metal-alloy fuel are described.

  9. Fuel compositions

    SciTech Connect

    Zaweski, E.F.; Niebylski, L.M.

    1986-08-05

    This patent describes distillate fuel for indirect injection compression ignition engines containing, in an amount sufficient to minimize coking, especially throttling nozzle coking in the prechambers or swirl chambers of indirect injection compression ignition engines operated on such fuel, at least the combination of (i) organic nitrate ignition accelerator and (ii) an esterified cycle dehydration product of sorbitol which, when added to the fuel in combination with the organic nitrate ignition accelerator minimizes the coking.

  10. Fuel cells 101

    SciTech Connect

    Hirschenhofer, J.H.

    1999-07-01

    This paper discusses the various types of fuel cells, the importance of cell voltage, fuel processing for natural gas, cell stacking, fuel cell plant description, advantages and disadvantages of the types of fuel cells, and applications. The types covered include: polymer electrolyte fuel cell, alkaline fuel cell, phosphoric acid fuel cell; molten carbonate fuel cell, and solid oxide fuel cell.

  11. Motor fuel

    SciTech Connect

    Burns, L.D.

    1982-07-13

    Liquid hydrocarbon fuel compositions are provided containing antiknock quantities of ashless antiknock agents comprising selected furyl compounds including furfuryl alcohol, furfuryl amine, furfuryl esters, and alkyl furoates.

  12. Fuel dehazers

    SciTech Connect

    Lyons, W.R.

    1986-03-01

    Hazy fuels can be caused by the emulsification of water into the fuel during refining, blending, or transportation operations. Detergent additive packages used in gasoline tend to emulsify water into the fuel. Fuels containing water haze can cause corrosion and contamination, and support microbiological growth. This results in problems. As the result of these problems, refiners, marketers, and product pipeline companies customarily have haze specifications. The haze specification may be a specific maximum water content or simply ''bright and clear'' at a specified temperature.

  13. Alternative fuels

    SciTech Connect

    Not Available

    1991-07-01

    This paper presents the preliminary results of a review, of the experiences of Brazil, Canada, and New Zealand, which have implemented programs to encourage the use of alternative motor fuels. It will also discuss the results of a separate completed review of the Department of Energy's (DOE) progress in implementing the Alternative Motor Fuels Act of 1988. The act calls for, among other things, the federal government to use alternative-fueled vehicles in its fleet. The Persian Gulf War, environmental concerns, and the administration's National Energy Strategy have greatly heightened interest in the use of alternative fuels in this country.

  14. Preliminary analysis of aircraft fuel systems for use with broadened specification jet fuels

    NASA Technical Reports Server (NTRS)

    Pasion, A. J.; Thomas, I.

    1977-01-01

    An analytical study was conducted on the use of broadened specification hydrocarbon fuels in present day aircraft. A short range Boeing 727 mission and three long range Boeing 747 missions were used as basis of calculation for one-day-per-year extreme values of fuel loading, airport ambient and altitude ambient temperatures with various seasonal and climatic conditions. Four hypothetical fuels were selected; two high-vapor-pressure fuels with 35 kPa and 70 kPa RVP and two high-freezing-point fuels with -29 C and -18 C freezing points. In-flight fuel temperatures were predicted by Boeing's aircraft fuel tank thermal analyzer computer program. Boil-off rates were calculated for the high vapor pressure fuels and heating/insulation requirements for the high freezing point fuels were established. Possible minor and major heating system modifications were investigated with respect to heat output, performance and economic penalties for the high freezing point fuels.

  15. Fuel injector

    DOEpatents

    Lambeth, Malcolm David Dick

    2001-02-27

    A fuel injector comprises first and second housing parts, the first housing part being located within a bore or recess formed in the second housing part, the housing parts defining therebetween an inlet chamber, a delivery chamber axially spaced from the inlet chamber, and a filtration flow path interconnecting the inlet and delivery chambers to remove particulate contaminants from the flow of fuel therebetween.

  16. Future Fuels

    DTIC Science & Technology

    2006-04-01

    financing, push technology and help motivate the building of the necessary manufacturing and distribution infrastructure. Hybrid Electric Vehicles , Tether...conclusions in three major areas: Hybrid Electric Vehicles (HEVs), fuel management during combat operations and manufactured fuels to address the...payoffs in the relatively near term, are: • Hybrid Electric Vehicles : The development of and commitment to hybrid electric architecture for TWVs

  17. A method of evaluating crown fuels in forest stands.

    Treesearch

    Rodney W. Sando; Charles H. Wick

    1972-01-01

    A method of describing the crown fuels in a forest fuel complex based on crown weight and crown volume was developed. A computer program is an integral part of the method. Crown weight data are presented in graphical form and are separated into hardwood and coniferous fuels. The fuel complex is described using total crown weight per acre, mean height to the base of...

  18. Computational and Experimental Study of the Structure of Diffusion Flames of Jet Fuel and Its Surrogates at Pressures up to 40 ATM

    DTIC Science & Technology

    2012-11-21

    fuel surrogates under incipient sooting conditions [1]. We refer to it as the Incipiently Sooting Flame (ISF). The doped flames have identical...the baseline flames. The top row pertains to the high-zf methane Blue Flame (BF) and the bottom row to the low-zf ethylene Incipiently Sooting Flame (ISF...The situation is reversed in ISF, the sooting flame where they matter the most, in which the model invariably overpredicts these aromatic

  19. A computer program (HEVSIM) for heavy duty vehicle fuel economy and performance simulation. Volume I: Description and analysis. Final report Mar-Oct 80

    SciTech Connect

    Buck, R.E.

    1981-09-01

    This report presents a description of a vehicle simulation program, which can determine the fuel economy and performance of a specified motor vehicle over a defined route as it executes a given driving schedule. Vehicle input accommodated by HEVSIM include accessories, engine, rear axle, converter, transmission, tires, aerodynamic drag coefficient, and shift logic. The report consists of three volumes. Volume I presents a description of the numerical approach and equations, Volume II is a user's manual, and Volume III contains the program listings.

  20. Fuel cell-fuel cell hybrid system

    DOEpatents

    Geisbrecht, Rodney A.; Williams, Mark C.

    2003-09-23

    A device for converting chemical energy to electricity is provided, the device comprising a high temperature fuel cell with the ability for partially oxidizing and completely reforming fuel, and a low temperature fuel cell juxtaposed to said high temperature fuel cell so as to utilize remaining reformed fuel from the high temperature fuel cell. Also provided is a method for producing electricity comprising directing fuel to a first fuel cell, completely oxidizing a first portion of the fuel and partially oxidizing a second portion of the fuel, directing the second fuel portion to a second fuel cell, allowing the first fuel cell to utilize the first portion of the fuel to produce electricity; and allowing the second fuel cell to utilize the second portion of the fuel to produce electricity.

  1. The spent fuel safety experiment

    SciTech Connect

    Harms, G.A.; Davis, F.J.; Ford, J.T.

    1995-08-01

    The Department of Energy is conducting an ongoing investigation of the consequences of taking fuel burnup into account in the design of spent fuel transportation packages. A series of experiments, collectively called the Spent Fuel Safety Experiment (SFSX), has been devised to provide integral benchmarks for testing computer-generated predictions of spent fuel behavior. A set of experiments is planned in which sections of unirradiated fuel rods are interchanged with similar sections of spent PWR fuel rods in a critical assembly. By determining the critical size of the arrays, one can obtain benchmark data for comparison with criticality safety calculations. The SFSX provides a direct measurement of the reactivity effects of spent PWR fuel using a well-characterized, spent fuel sample. The SFSX also provides an experimental measurement of the end-effect, i.e., the reactivity effect of the variation of the burnup profile at the ends of PWR fuel rods. The design of the SFSX is optimized to yield accurate benchmark measurements of the effects of interest, well above experimental uncertainties.

  2. Fuels research: Fuel thermal stability overview

    NASA Technical Reports Server (NTRS)

    Cohen, S. M.

    1980-01-01

    Alternative fuels or crude supplies are examined with respect to satisfying aviation fuel needs for the next 50 years. The thermal stability of potential future fuels is discussed and the effects of these characteristics on aircraft fuel systems are examined. Advanced fuel system technology and design guidelines for future fuels with lower thermal stability are reported.

  3. FUEL ELEMENT

    DOEpatents

    Bean, R.W.

    1963-11-19

    A ceramic fuel element for a nuclear reactor that has improved structural stability as well as improved cooling and fission product retention characteristics is presented. The fuel element includes a plurality of stacked hollow ceramic moderator blocks arranged along a tubular raetallic shroud that encloses a series of axially apertured moderator cylinders spaced inwardly of the shroud. A plurality of ceramic nuclear fuel rods are arranged in the annular space between the shroud and cylinders of moderator and appropriate support means and means for directing gas coolant through the annular space are also provided. (AEC)

  4. Fuel ethanol

    SciTech Connect

    Not Available

    1989-02-01

    This report discusses the Omnibus Trade and Competitiveness Act of 1988 which requires GAO to examine fuel ethanol imports from Central America and the Caribbean and their impact on the U.S. fuel ethanol industry. Ethanol is the alcohol in beverages, such as beer, wine, and whiskey. It can also be used as a fuel by blending with gasoline. It can be made from renewable resources, such as corn, wheat, grapes, and sugarcane, through a process of fermentation. This report finds that, given current sugar and gasoline prices, it is not economically feasible for Caribbean ethanol producers to meet the current local feedstock requirement.

  5. Shuttle Fuel Feedliner Cracking Investigation

    NASA Technical Reports Server (NTRS)

    Nesman, Tomas E.; Turner, Jim (Technical Monitor)

    2002-01-01

    This presentation provides an overview of material covered during 'Space Shuttle Fuel Feedliner Cracking Investigation MSFC Fluids Workshop' held November 19-21, 2002. Topics covered include: cracks on fuel feed lines of Orbiter space shuttles, fluid driven cracking analysis, liner structural modes, structural motion in a fluid, fluid borne drivers, three dimensional computational fluid dynamics models, fluid borne drivers from pumps, amplification mechanisms, flow parameter mapping, and flight engine flow map.

  6. Fuel composition

    SciTech Connect

    Badger, S.L.

    1983-09-20

    A composition useful, inter alia, as a fuel, is based on ethyl alcohol denatured with methylisobutyl alcohol and kerosene, which is mixed with xylenes and isopropyl alcohol. The xylenes and isopropyl alcohol act with the denaturizing agents to raise the flash point above that of ethyl alcohol alone and also to mask the odor and color the flame, thus making the composition safer for use as a charcoal lighter or as a fuel for e.g. patio lamps.

  7. Nuclear fuel cycle facility accident analysis handbook

    SciTech Connect

    Ayer, J E; Clark, A T; Loysen, P; Ballinger, M Y; Mishima, J; Owczarski, P C; Gregory, W S; Nichols, B D

    1988-05-01

    The Accident Analysis Handbook (AAH) covers four generic facilities: fuel manufacturing, fuel reprocessing, waste storage/solidification, and spent fuel storage; and six accident types: fire, explosion, tornado, criticality, spill, and equipment failure. These are the accident types considered to make major contributions to the radiological risk from accidents in nuclear fuel cycle facility operations. The AAH will enable the user to calculate source term releases from accident scenarios manually or by computer. A major feature of the AAH is development of accident sample problems to provide input to source term analysis methods and transport computer codes. Sample problems and illustrative examples for different accident types are included in the AAH.

  8. High-freezing-point fuel studies

    NASA Technical Reports Server (NTRS)

    Tolle, F. F.

    1980-01-01

    Considerable progress in developing the experimental and analytical techniques needed to design airplanes to accommodate fuels with less stringent low temperature specifications is reported. A computer technique for calculating fuel temperature profiles in full tanks was developed. The computer program is being extended to include the case of partially empty tanks. Ultimately, the completed package is to be incorporated into an aircraft fuel tank thermal analyser code to permit the designer to fly various thermal exposure patterns, study fuel temperatures versus time, and determine holdup.

  9. A computer program (HEVSIM) for heavy duty vehicle fuel economy and performance simulation. Volume III: Appendices A through F. Final report Mar-Oct 80

    SciTech Connect

    Buck, R.E.

    1981-09-01

    Volume III is the third and last volume of a three volume document describing the computer program HEVSIM. This volume includes appendices which list the HEVSIM program, sample part data, some typical outputs and updated nomenclature.

  10. The Assessment of Fuel Cell Power Plants for Surface Combatants.

    DTIC Science & Technology

    1994-09-30

    fuel cell technology on the design and effectiveness of future naval surface combatants. The study involved the collection of data to characterize four different fuel cell technologies; proton exchange membrane, molten carbonate, phosphoric acid, and solid oxide fuel cells. This information was used to expand current computer models to develop specific fuel cell plants that met the power requirements for several applications on a nominal 5000 Lton destroyer and a nominal 200 Lton corvette. Each of the fuel cell

  11. Alternative jet aircraft fuels

    NASA Technical Reports Server (NTRS)

    Grobman, J.

    1979-01-01

    Potential changes in jet aircraft fuel specifications due to shifts in supply and quality of refinery feedstocks are discussed with emphasis on the effects these changes would have on the performance and durability of aircraft engines and fuel systems. Combustion characteristics, fuel thermal stability, and fuel pumpability at low temperature are among the factors considered. Combustor and fuel system technology needs for broad specification fuels are reviewed including prevention of fuel system fouling and fuel system technology for fuels with higher freezing points.

  12. Alternative jet aircraft fuels

    NASA Technical Reports Server (NTRS)

    Grobman, J.

    1979-01-01

    Potential changes in jet aircraft fuel specifications due to shifts in supply and quality of refinery feedstocks are discussed with emphasis on the effects these changes would have on the performance and durability of aircraft engines and fuel systems. Combustion characteristics, fuel thermal stability, and fuel pumpability at low temperature are among the factors considered. Combustor and fuel system technology needs for broad specification fuels are reviewed including prevention of fuel system fouling and fuel system technology for fuels with higher freezing points.

  13. Reforming of fuel inside fuel cell generator

    DOEpatents

    Grimble, Ralph E.

    1988-01-01

    Disclosed is an improved method of reforming a gaseous reformable fuel within a solid oxide fuel cell generator, wherein the solid oxide fuel cell generator has a plurality of individual fuel cells in a refractory container, the fuel cells generating a partially spent fuel stream and a partially spent oxidant stream. The partially spent fuel stream is divided into two streams, spent fuel stream I and spent fuel stream II. Spent fuel stream I is burned with the partially spent oxidant stream inside the refractory container to produce an exhaust stream. The exhaust stream is divided into two streams, exhaust stream I and exhaust stream II, and exhaust stream I is vented. Exhaust stream II is mixed with spent fuel stream II to form a recycle stream. The recycle stream is mixed with the gaseous reformable fuel within the refractory container to form a fuel stream which is supplied to the fuel cells. Also disclosed is an improved apparatus which permits the reforming of a reformable gaseous fuel within such a solid oxide fuel cell generator. The apparatus comprises a mixing chamber within the refractory container, means for diverting a portion of the partially spent fuel stream to the mixing chamber, means for diverting a portion of exhaust gas to the mixing chamber where it is mixed with the portion of the partially spent fuel stream to form a recycle stream, means for injecting the reformable gaseous fuel into the recycle stream, and means for circulating the recycle stream back to the fuel cells.

  14. Reforming of fuel inside fuel cell generator

    DOEpatents

    Grimble, R.E.

    1988-03-08

    Disclosed is an improved method of reforming a gaseous reformable fuel within a solid oxide fuel cell generator, wherein the solid oxide fuel cell generator has a plurality of individual fuel cells in a refractory container, the fuel cells generating a partially spent fuel stream and a partially spent oxidant stream. The partially spent fuel stream is divided into two streams, spent fuel stream 1 and spent fuel stream 2. Spent fuel stream 1 is burned with the partially spent oxidant stream inside the refractory container to produce an exhaust stream. The exhaust stream is divided into two streams, exhaust stream 1 and exhaust stream 2, and exhaust stream 1 is vented. Exhaust stream 2 is mixed with spent fuel stream 2 to form a recycle stream. The recycle stream is mixed with the gaseous reformable fuel within the refractory container to form a fuel stream which is supplied to the fuel cells. Also disclosed is an improved apparatus which permits the reforming of a reformable gaseous fuel within such a solid oxide fuel cell generator. The apparatus comprises a mixing chamber within the refractory container, means for diverting a portion of the partially spent fuel stream to the mixing chamber, means for diverting a portion of exhaust gas to the mixing chamber where it is mixed with the portion of the partially spent fuel stream to form a recycle stream, means for injecting the reformable gaseous fuel into the recycle stream, and means for circulating the recycle stream back to the fuel cells. 1 fig.

  15. FUEL ELEMENT

    DOEpatents

    Fortescue, P.; Zumwalt, L.R.

    1961-11-28

    A fuel element was developed for a gas cooled nuclear reactor. The element is constructed in the form of a compacted fuel slug including carbides of fissionable material in some cases with a breeder material carbide and a moderator which slug is disposed in a canning jacket of relatively impermeable moderator material. Such canned fuel slugs are disposed in an elongated shell of moderator having greater gas permeability than the canning material wherefore application of reduced pressure to the space therebetween causes gas diffusing through the exterior shell to sweep fission products from the system. Integral fission product traps and/or exterior traps as well as a fission product monitoring system may be employed therewith. (AEC)

  16. Fuel bundle

    SciTech Connect

    Lui, C.K.

    1989-04-04

    This patent describes a method of forming a fuel bundle of a nuclear reactor. The method consists of positioning the fuel rods in the bottom plate, positioning the tie rod in the bottom plate with the key passed through the receptacle to the underside of the bottom plate and, after the tie rod is so positioned, turning the tie rod so that the key is in engagement with the underside of the bottom plate. Thereafter mounting the top plate is mounted in engagement with the fuel rods with the upper end of the tie rod extending through the opening in the top plate and extending above the top plate, and the tie rod is secured to the upper side of sid top plate thus simultaneously securing the key to the underside of the bottom plate.

  17. FUEL ELEMENT

    DOEpatents

    Howard, R.C.; Bokros, J.C.

    1962-03-01

    A fueled matrlx eontnwinlng uncomblned carbon is deslgned for use in graphlte-moderated gas-cooled reactors designed for operatlon at temperatures (about 1500 deg F) at which conventional metallic cladding would ordlnarily undergo undesired carburization or physical degeneratlon. - The invention comprlses, broadly a fuel body containlng uncombined earbon, clad with a nickel alloy contalning over about 28 percent by' weight copper in the preferred embodlment. Thls element ls supporirted in the passageways in close tolerance with the walls of unclad graphite moderator materlal. (AEC)

  18. Fuels characterization studies. [jet fuels

    NASA Technical Reports Server (NTRS)

    Seng, G. T.; Antoine, A. C.; Flores, F. J.

    1980-01-01

    Current analytical techniques used in the characterization of broadened properties fuels are briefly described. Included are liquid chromatography, gas chromatography, and nuclear magnetic resonance spectroscopy. High performance liquid chromatographic ground-type methods development is being approached from several directions, including aromatic fraction standards development and the elimination of standards through removal or partial removal of the alkene and aromatic fractions or through the use of whole fuel refractive index values. More sensitive methods for alkene determinations using an ultraviolet-visible detector are also being pursued. Some of the more successful gas chromatographic physical property determinations for petroleum derived fuels are the distillation curve (simulated distillation), heat of combustion, hydrogen content, API gravity, viscosity, flash point, and (to a lesser extent) freezing point.

  19. Future Fuel.

    ERIC Educational Resources Information Center

    Stover, Del

    1991-01-01

    Tough new environmental laws, coupled with fluctuating oil prices, are likely to prompt hundreds of school systems to examine alternative fuels. Literature reviews and interviews with 45 government, education, and industry officials provided data for a comparative analysis of gasoline, diesel, natural gas, methanol, and propane. (MLF)

  20. Future Fuel.

    ERIC Educational Resources Information Center

    Stover, Del

    1991-01-01

    Tough new environmental laws, coupled with fluctuating oil prices, are likely to prompt hundreds of school systems to examine alternative fuels. Literature reviews and interviews with 45 government, education, and industry officials provided data for a comparative analysis of gasoline, diesel, natural gas, methanol, and propane. (MLF)

  1. Nuclear Fuels.

    ERIC Educational Resources Information Center

    Nash, J. Thomas

    1983-01-01

    Trends in and factors related to the nuclear industry and nuclear fuel production are discussed. Topics addressed include nuclear reactors, survival of the U.S. uranium industry, production costs, budget cuts by the Department of Energy and U.S. Geological survey for resource studies, mining, and research/development activities. (JN)

  2. Nuclear Fuels.

    ERIC Educational Resources Information Center

    Nash, J. Thomas

    1983-01-01

    Trends in and factors related to the nuclear industry and nuclear fuel production are discussed. Topics addressed include nuclear reactors, survival of the U.S. uranium industry, production costs, budget cuts by the Department of Energy and U.S. Geological survey for resource studies, mining, and research/development activities. (JN)

  3. Fuel Cells

    ERIC Educational Resources Information Center

    Hawkins, M. D.

    1973-01-01

    Discusses the theories, construction, operation, types, and advantages of fuel cells developed by the American space programs. Indicates that the cell is an ideal small-scale power source characterized by its compactness, high efficiency, reliability, and freedom from polluting fumes. (CC)

  4. Fuel Cells

    ERIC Educational Resources Information Center

    Hawkins, M. D.

    1973-01-01

    Discusses the theories, construction, operation, types, and advantages of fuel cells developed by the American space programs. Indicates that the cell is an ideal small-scale power source characterized by its compactness, high efficiency, reliability, and freedom from polluting fumes. (CC)

  5. A computer program (HEVSIM) for heavy duty vehicle fuel economy and performance simulation. Volume II: Users' manual. Final report Mar-Oct 80

    SciTech Connect

    Buck, R.E.

    1981-09-01

    Volume II is the second volume of a three volume document describing the computer program HEVSIM for use with buses and heavy duty trucks. This volume is a user's manual describing how to prepare data input and execute the program. A strong effort has been made to prepare this manual from a user's viewpoint. Sample cases have been included to illustrate the various simulation methods available, and the most frequently used HEVSIM options.

  6. Uncertainty Analyses of Advanced Fuel Cycles

    SciTech Connect

    Laurence F. Miller; J. Preston; G. Sweder; T. Anderson; S. Janson; M. Humberstone; J. MConn; J. Clark

    2008-12-12

    The Department of Energy is developing technology, experimental protocols, computational methods, systems analysis software, and many other capabilities in order to advance the nuclear power infrastructure through the Advanced Fuel Cycle Initiative (AFDI). Our project, is intended to facilitate will-informed decision making for the selection of fuel cycle options and facilities for development.

  7. Wood fueled boiler financial feasibility user's manual

    Treesearch

    Robert Govett; Scott Bowe; Terry Mace; Steve Hubbard; John (Rusty) Dramm; Richard Bergman

    2005-01-01

    “Wood Fueled Boiler Financial Feasibility” is a spreadsheet program designed for easy use on a personal computer. This program provides a starting point for interested parties to perform financial feasibility analysis of a steam boiler system for space heating or process heat. By allowing users to input the conditions applicable to their current or proposed fuel...

  8. Advanced Fuel Cycle Cost Basis

    SciTech Connect

    D. E. Shropshire; K. A. Williams; W. B. Boore; J. D. Smith; B. W. Dixon; M. Dunzik-Gougar; R. D. Adams; D. Gombert; E. Schneider

    2009-12-01

    This report, commissioned by the U.S. Department of Energy (DOE), provides a comprehensive set of cost data supporting a cost analysis for the relative economic comparison of options for use in the Advanced Fuel Cycle Initiative (AFCI) Program. The report describes the AFCI cost basis development process, reference information on AFCI cost modules, a procedure for estimating fuel cycle costs, economic evaluation guidelines, and a discussion on the integration of cost data into economic computer models. This report contains reference cost data for 25 cost modules—23 fuel cycle cost modules and 2 reactor modules. The cost modules were developed in the areas of natural uranium mining and milling, conversion, enrichment, depleted uranium disposition, fuel fabrication, interim spent fuel storage, reprocessing, waste conditioning, spent nuclear fuel (SNF) packaging, long-term monitored retrievable storage, near surface disposal of low-level waste (LLW), geologic repository and other disposal concepts, and transportation processes for nuclear fuel, LLW, SNF, transuranic, and high-level waste.

  9. Advanced Fuel Cycle Cost Basis

    SciTech Connect

    D. E. Shropshire; K. A. Williams; W. B. Boore; J. D. Smith; B. W. Dixon; M. Dunzik-Gougar; R. D. Adams; D. Gombert

    2007-04-01

    This report, commissioned by the U.S. Department of Energy (DOE), provides a comprehensive set of cost data supporting a cost analysis for the relative economic comparison of options for use in the Advanced Fuel Cycle Initiative (AFCI) Program. The report describes the AFCI cost basis development process, reference information on AFCI cost modules, a procedure for estimating fuel cycle costs, economic evaluation guidelines, and a discussion on the integration of cost data into economic computer models. This report contains reference cost data for 26 cost modules—24 fuel cycle cost modules and 2 reactor modules. The cost modules were developed in the areas of natural uranium mining and milling, conversion, enrichment, depleted uranium disposition, fuel fabrication, interim spent fuel storage, reprocessing, waste conditioning, spent nuclear fuel (SNF) packaging, long-term monitored retrievable storage, near surface disposal of low-level waste (LLW), geologic repository and other disposal concepts, and transportation processes for nuclear fuel, LLW, SNF, and high-level waste.

  10. Advanced Fuel Cycle Cost Basis

    SciTech Connect

    D. E. Shropshire; K. A. Williams; W. B. Boore; J. D. Smith; B. W. Dixon; M. Dunzik-Gougar; R. D. Adams; D. Gombert; E. Schneider

    2008-03-01

    This report, commissioned by the U.S. Department of Energy (DOE), provides a comprehensive set of cost data supporting a cost analysis for the relative economic comparison of options for use in the Advanced Fuel Cycle Initiative (AFCI) Program. The report describes the AFCI cost basis development process, reference information on AFCI cost modules, a procedure for estimating fuel cycle costs, economic evaluation guidelines, and a discussion on the integration of cost data into economic computer models. This report contains reference cost data for 25 cost modules—23 fuel cycle cost modules and 2 reactor modules. The cost modules were developed in the areas of natural uranium mining and milling, conversion, enrichment, depleted uranium disposition, fuel fabrication, interim spent fuel storage, reprocessing, waste conditioning, spent nuclear fuel (SNF) packaging, long-term monitored retrievable storage, near surface disposal of low-level waste (LLW), geologic repository and other disposal concepts, and transportation processes for nuclear fuel, LLW, SNF, transuranic, and high-level waste.

  11. Fuel property effects on fuel/air mixing in an experimental diesel engine

    SciTech Connect

    Browne, K.R.; Patridge, I.M.; Greeves, G.

    1986-01-01

    Fuels of widely varying properties are studied by injection of a single and well defined spray into an experimental diesel engine. Three optical techniques were developed to visualise liquid fuel, fuel vapour, flame, soot and individual droplets and their associated vapour trails. Liquid core length measurements are presented for diesel fuel, toluene, ethanol and sunflower oil. Computer model predictions show that an increase of the fuel mid-boiling point by 40/sup 0/C gives a similar effect on liquid core length to an increase of 0.03mm in the nozzle hole diameter.

  12. Seismic analysis of freestanding fuel racks

    SciTech Connect

    Gilmore, C.B.

    1982-01-01

    This paper presents a nonlinear transient dynamic time-history analysis of freestanding spent fuel storage racks subjected to seismic excitation. This type of storage rack is structurally unrestrained and submerged in water in the spent fuel pool of a nuclear power complex, holds (spent) fuel assemblies which have been removed from the reactor core. Nonlinearities in the fuel rack system include impact between the fuel assembly and surrounding cell due to clearances between them, friction due to sliding between the fuel rack support structure and spent fuel pool floor, and the lift-off of the fuel rack support structure from the spent fuel pool floor. The analysis of the fuel rack system includes impacting due to gap closures, energy losses due to impacting bodies, Coulomb damping between sliding surfaces, and hydrodynamic mass effects. Acceleration time history excitation development is discussed. Modeling considerations, such as the initial status of nonlinear elements, number of mode shapes to include in the analysis, modal damping, and integration time-step size are presented. The response of the fuel rack subjected to two-dimensional seismic excitation is analyzed by the modal superposition method, which has resulted in significant computer cost savings when compared to that of direct integration.

  13. Fuel cell

    SciTech Connect

    Struthers, R.C.

    1983-06-28

    An improved fuel cell comprising an anode section including an anode terminal, an anode fuel, and an anolyte electrolyte, a cathode section including a cathode terminal, an electron distributor and a catholyte electrolyte, an ion exchange section between the anode and cathode sections and including an ionolyte electrolyte, ion transfer membranes separating the ionolyte from the anolyte and the catholyte and an electric circuit connected with and between the terminals conducting free electrons from the anode section and delivering free electrons to the cathode section, said ionolyte receives ions of one polarity moving from the anolyte through the membrane related thereto preventing chemical equilibrium in the anode section and sustaining chemical reaction and the generating of free electrons therein, said ions received by the ionolyte from the anolyte release different ions from the ionolyte which move through the membrane between the ionolyte and catholyte and which add to the catholyte.

  14. Moisture content calculations for 1000-hour timelag fuels

    Treesearch

    Michael A. Fosberg; Richard C. Rothermel; Patricia L. Andrews

    1981-01-01

    Techniques to calculate 1000-hour timelag fuel moistures were developed from theory of water movement in wood. The 1000-hour timelag fuel moisture is computed from mean daily temperatures and humidities and precipitation duration. Comparison of calculated and observed fuel moistures showed good agreement. Techniques to determine the seasonal starting value of the 1000-...

  15. Fuel conditioner

    SciTech Connect

    Nelson, M.L.; Nelson, O.L. Jr.

    1988-06-28

    A fuel conditioner is described comprising 10 to 80% of a polar oxygenated hydrocarbon having an average molecular weight from about 250 to about 500, an acid acid number from about 25 to about 125, and a saponification number from about 30 to about 250; and 5 to 50% of an oxygenated compatibilizing agent having a solubility parameter of from about 8.8 to about 11.5 and moderate to strong hydrogen-bonding capacity.

  16. Fuel additives

    SciTech Connect

    Gheysens, J.L.G.

    1990-11-27

    This patent describes a composition for the improvement of hydrocarbon fuels exhibiting a boiling range of gasoline being suitable for use in spark ignition-type engines. It comprises an aromatic amine; a polyaminated detergent; a catalyst comprising a colloidal suspension or amine salt of transition/alkali/alkaline earth metal organic coordinations having at least one metal oxidehydroxide linked to an alkyl chain via a carboxyl group; and a solvent comprising an alkanol-aliphatic ether oxygenated hydrocarbon.

  17. Used fuel disposition in crystalline rocks

    SciTech Connect

    Wang, Y.; Hadgu, Teklu; Kalinina, Elena Arkadievna; Jerden, James L.; Copple, Jacqueline M.; Cruse, T.; Ebert, W.; Buck, E.; Eittman, R.; Tinnacher, R.; Tournassat, Christophe.; Davis, J.; Viswanathan, H.; Chu, S.; Dittrich, T.; Hyman, F.; Karra, S.; Makedonska, N.; Reimus, P.; Zavarin, Mavrik; Joseph, C.

    2016-09-01

    The U.S. Department of Energy Office of Nuclear Energy, Office of Fuel Cycle Technology established the Used Fuel Disposition Campaign (UFDC) in fiscal year 2010 (FY10) to conduct the research and development (R&D) activities related to storage, transportation and disposal of used nuclear fuel and high level nuclear waste. The objective of the Crystalline Disposal R&D Work Package is to advance our understanding of long-term disposal of used fuel in crystalline rocks and to develop necessary experimental and computational capabilities to evaluate various disposal concepts in such media.

  18. Consequence Analysis for Used Fuel Extended Storage

    SciTech Connect

    Dunn, Timothy; Gerhard, Michael; Sutton, Mark; Wen, Josh

    2014-09-23

    Early identification and evaluation of security issues related to the extended storage of used nuclear fuel is critical. A breach in a dry fuel storage container has the possibility of external gas from the atmosphere interacting with the used fuel rods at high temperatures, resulting in rapid oxidation and possibly the ignition of a zirconium fire. In support of this idea, the current work aims to develop a computational model of heat transfer and fluid flow in and through a breached dry fuel storage cask to determine if the resulting flow conditions are likely to result in a fire.

  19. Alcohol fuels

    SciTech Connect

    Not Available

    1990-07-01

    Ethanol is an alcohol made from grain that can be blended with gasoline to extend petroleum supplies and to increase gasoline octane levels. Congressional proposals to encourage greater use of alternative fuels could increase the demand for ethanol. This report evaluates the growth potential of the ethanol industry to meet future demand increases and the impacts increased production would have on American agriculture and the federal budget. It is found that ethanol production could double or triple in the next eight years, and that American farmers could provide the corn for this production increase. While corn growers would benefit, other agricultural segments would not; soybean producers, for example could suffer for increased corn oil production (an ethanol byproduct) and cattle ranchers would be faced with higher feed costs because of higher corn prices. Poultry farmers might benefit from lower priced feed. Overall, net farm cash income should increase, and consumers would see slightly higher food prices. Federal budget impacts would include a reduction in federal farm program outlays by an annual average of between $930 million (for double current production of ethanol) to $1.421 billion (for triple production) during the eight-year growth period. However, due to an partial tax exemption for ethanol blended fuels, federal fuel tax revenues could decrease by between $442 million and $813 million.

  20. LMFBR fuel component costs

    SciTech Connect

    Epperson, E.M.; Borisch, R.R.; Rice, L.H.

    1981-10-29

    A significant portion of the cost of fabricating LMFBR fuels is in the non-fuel components such as fuel pin cladding, fuel assembly ducts and end fittings. The contribution of these to fuel fabrication costs, based on FFTF experience and extrapolated to large LMFBR fuel loadings, is discussed. The extrapolation considers the expected effects of LMFBR development programs in progress on non-fuel component costs.

  1. Combined Experimental and Computational Study on the Unimolecular Decomposition of JP-8 Jet Fuel Surrogates. II: n-Dodecane (n-C12H26).

    PubMed

    Zhao, Long; Yang, Tao; Kaiser, Ralf I; Troy, Tyler P; Ahmed, Musahid; Ribeiro, Joao Marcelo; Belisario-Lara, Daniel; Mebel, Alexander M

    2017-02-16

    We investigated temperature-dependent products in the pyrolysis of helium-seeded n-dodecane, which represents a surrogate of the n-alkane fraction of Jet Propellant-8 (JP-8) aviation fuel. The experiments were performed in a high temperature chemical reactor over a temperature range of 1200 K to 1600 K at a pressure of 600 Torr, with in situ identification of the nascent products in a supersonic molecular beam using single photon vacuum ultraviolet (VUV) photoionization coupled with the analysis of the ions in a reflectron time-of-flight mass spectrometer (ReTOF). For the first time, the initial decomposition products of n-dodecane-including radicals and thermally labile closed-shell species-were probed in experiments, which effectively exclude mass growth processes. A total of 15 different products were identified, such as molecular hydrogen (H2), C2 to C7 1-alkenes [ethylene (C2H4) to 1-heptene (C7H14)], C1-C3 radicals [methyl (CH3), ethyl (C2H5), allyl (C3H5)], small C1-C3 hydrocarbons [acetylene (C2H2), allene (C3H4), methylacetylene (C3H4)], as well as the reaction products [1,3-butadiene (C4H6), 2-butene (C4H8)] attributed to higher-order processes. Electronic structure calculations carried out at the G3(CCSD,MP2)//B3LYP/6-311G(d,p) level of theory combined with RRKM/master equation of rate constants for relevant reaction steps showed that n-dodecane decomposes initially by a nonterminal C-C bond cleavage and producing a mixture of alkyl radicals from ethyl to decyl with approximately equal branching ratios. The alkyl radicals appear to be unstable under the experimental conditions and to rapidly dissociate either directly by C-C bond β-scission to produce ethylene (C2H4) plus a smaller 1-alkyl radical with the number of carbon atoms diminished by two or via 1,5-, 1,6-, or 1,7- 1,4-, 1,9-, or 1,8-H shifts followed by C-C β-scission producing alkenes from propene to 1-nonene together with smaller 1-alkyl radicals. The stability and hence the branching ratios

  2. Automated Fuel Element Closure Welding System

    SciTech Connect

    Wahlquist, D.R.

    1993-03-01

    The Automated Fuel Element Closure Welding System is a robotic device that will load and weld top end plugs onto nuclear fuel elements in a highly radioactive and inert gas environment. The system was developed at Argonne National Laboratory-West as part of the Fuel Cycle Demonstration. The welding system performs four main functions, it (1) injects a small amount of a xenon/krypton gas mixture into specific fuel elements, and (2) loads tiny end plugs into the tops of fuel element jackets, and (3) welds the end plugs to the element jackets, and (4) performs a dimensional inspection of the pre- and post-welded fuel elements. The system components are modular to facilitate remote replacement of failed parts. The entire system can be operated remotely in manual, semi-automatic, or fully automatic modes using a computer control system. The welding system is currently undergoing software testing and functional checkout.

  3. Automated Fuel Element Closure Welding System

    SciTech Connect

    Wahlquist, D.R.

    1993-01-01

    The Automated Fuel Element Closure Welding System is a robotic device that will load and weld top end plugs onto nuclear fuel elements in a highly radioactive and inert gas environment. The system was developed at Argonne National Laboratory-West as part of the Fuel Cycle Demonstration. The welding system performs four main functions, it (1) injects a small amount of a xenon/krypton gas mixture into specific fuel elements, and (2) loads tiny end plugs into the tops of fuel element jackets, and (3) welds the end plugs to the element jackets, and (4) performs a dimensional inspection of the pre- and post-welded fuel elements. The system components are modular to facilitate remote replacement of failed parts. The entire system can be operated remotely in manual, semi-automatic, or fully automatic modes using a computer control system. The welding system is currently undergoing software testing and functional checkout.

  4. Diesel injector carbonization by three alternative fuels

    SciTech Connect

    Goodrum, J.W.; Patel, V.C.; McClendon, R.W.

    1996-05-01

    Three alternative diesel fuels were screened by analysis of fuel injector tip deposits. The test engines were operated on the Peterson (torque) test cycle; the average carbon deposit volume on an injector tip was measured by a computer vision method. Relative coke deposit quantity was obtained by area analysis of injector tip images. Repetitive image areas varied less than 1%. Coke deposit areas for repetitive fuel tests also varied less than 1%. Injector coking tendencies of tested fuels decreased in the following order: peanut oil, no. 2 diesel, tricaprylin, and tributyrin/no. 2 diesel blend. The observed dependence of the relative coke quantity on fuel type was consistent with the results from a photographic technique used previously for fuel screening. 10 refs., 2 figs., 2 tabs.

  5. Micro-Tubular Fuel Cells

    NASA Technical Reports Server (NTRS)

    Kimble, Michael C.; Anderson, Everett B.; Jayne, Karen D.; Woodman, Alan S.

    2004-01-01

    Micro-tubular fuel cells that would operate at power levels on the order of hundreds of watts or less are under development as alternatives to batteries in numerous products - portable power tools, cellular telephones, laptop computers, portable television receivers, and small robotic vehicles, to name a few examples. Micro-tubular fuel cells exploit advances in the art of proton-exchange-membrane fuel cells. The main advantage of the micro-tubular fuel cells over the plate-and-frame fuel cells would be higher power densities: Whereas the mass and volume power densities of low-pressure hydrogen-and-oxygen-fuel plate-and-frame fuel cells designed to operate in the targeted power range are typically less than 0.1 W/g and 0.1 kW/L, micro-tubular fuel cells are expected to reach power densities much greater than 1 W/g and 1 kW/L. Because of their higher power densities, micro-tubular fuel cells would be better for powering portable equipment, and would be better suited to applications in which there are requirements for modularity to simplify maintenance or to facilitate scaling to higher power levels. The development of PEMFCs has conventionally focused on producing large stacks of cells that operate at typical power levels >5 kW. The usual approach taken to developing lower-power PEMFCs for applications like those listed above has been to simply shrink the basic plate-and-frame configuration to smaller dimensions. A conventional plate-and-frame fuel cell contains a membrane/electrode assembly in the form of a flat membrane with electrodes of the same active area bonded to both faces. In order to provide reactants to both electrodes, bipolar plates that contain flow passages are placed on both electrodes. The mass and volume overhead of the bipolar plates amounts to about 75 percent of the total mass and volume of a fuel-cell stack. Removing these bipolar plates in the micro-tubular fuel cell significantly increases the power density.

  6. Novel experimental technique for 3D investigation of high-speed cavitating diesel fuel flows by X-ray micro computed tomography

    NASA Astrophysics Data System (ADS)

    Lorenzi, M.; Mitroglou, N.; Santini, M.; Gavaises, M.

    2017-03-01

    An experimental technique for the estimation of the temporal-averaged vapour volume fraction within high-speed cavitating flow orifices is presented. The scientific instrument is designed to employ X-ray micro computed tomography (microCT) as a quantitative 3D measuring technique applied to custom designed, large-scale, orifice-type flow channels made from Polyether-ether-ketone (PEEK). The attenuation of the ionising electromagnetic radiation by the fluid under examination depends on its local density; the transmitted radiation through the cavitation volume is compared to the incident radiation, and combination of radiographies from sufficient number of angles leads to the reconstruction of attenuation coefficients versus the spatial position. This results to a 3D volume fraction distribution measurement of the developing multiphase flow. The experimental results obtained are compared against the high speed shadowgraph visualisation images obtained in an optically transparent nozzle with identical injection geometry; comparison between the temporal mean image and the microCT reconstruction shows excellent agreement. At the same time, the real 3D internal channel geometry (possibly eroded) has been measured and compared to the nominal manufacturing CAD drawing of the test nozzle.

  7. Novel experimental technique for 3D investigation of high-speed cavitating diesel fuel flows by X-ray micro computed tomography.

    PubMed

    Lorenzi, M; Mitroglou, N; Santini, M; Gavaises, M

    2017-03-01

    An experimental technique for the estimation of the temporal-averaged vapour volume fraction within high-speed cavitating flow orifices is presented. The scientific instrument is designed to employ X-ray micro computed tomography (microCT) as a quantitative 3D measuring technique applied to custom designed, large-scale, orifice-type flow channels made from Polyether-ether-ketone (PEEK). The attenuation of the ionising electromagnetic radiation by the fluid under examination depends on its local density; the transmitted radiation through the cavitation volume is compared to the incident radiation, and combination of radiographies from sufficient number of angles leads to the reconstruction of attenuation coefficients versus the spatial position. This results to a 3D volume fraction distribution measurement of the developing multiphase flow. The experimental results obtained are compared against the high speed shadowgraph visualisation images obtained in an optically transparent nozzle with identical injection geometry; comparison between the temporal mean image and the microCT reconstruction shows excellent agreement. At the same time, the real 3D internal channel geometry (possibly eroded) has been measured and compared to the nominal manufacturing CAD drawing of the test nozzle.

  8. Fuel utilization and fuel sensitivity of solid oxide fuel cells

    NASA Astrophysics Data System (ADS)

    Huang, Kevin

    2011-03-01

    Fuel utilization and fuel sensitivity are two important process variables widely used in operation of SOFC cells, stacks, and generators. To illustrate the technical values, the definitions of these two variables as well as practical examples are particularly given in this paper. It is explicitly shown that the oxygen-leakage has a substantial effect on the actual fuel utilization, fuel sensitivity and V-I characteristics. An underestimation of the leakage flux could potentially results in overly consuming fuel and oxidizing Ni-based anode. A fuel sensitivity model is also proposed to help extract the leakage flux information from a fuel sensitivity curve. Finally, the "bending-over" phenomenon observed in the low-current range of a V-I curve measured at constant fuel-utilization is quantitatively coupled with leakage flux.

  9. Analysis of Double-encapsulated Fuel Rods

    SciTech Connect

    Hales, Jason Dean; Medvedev, Pavel G; Novascone, Stephen Rhead; Perez, Danielle Marie; Williamson, Richard L

    2014-09-01

    In an LWR fuel rod, the cladding encapsulates the fuel, contains fission products, and transfers heat directly to the water coolant. In some situations, it may be advantageous to separate the cladding from the coolant through use of a secondary cladding or capsule. This may be done to increase confidence that the fuel or fission products will not mix with the coolant, to provide a mechanism for controlling the rod temperature, or to place multiple experimental rodlets within a single housing. With an axisymmetric assumption, it is possible to derive closed-form expressions for the temperature profile in a fuel rod using radially-constant thermal conductivity in the fuel. This is true for both a traditional fuel-cladding rod and a double-encapsulated fuel (fuel, cladding, capsule) configuration. Likewise, it is possible to employ a fuel performance code to analyse both a traditional and a double-encapsulated fuel. In the case of the latter, two sets of gap heat transfer conditions must be imposed. In this work, we review the equations associated with radial heat transfer in a cylindrical system, present analytic and computational results for a postulated power and gas mixture history for IFA-744, and describe the analysis of the AFC-2A, 2B metallic fuel alloy experiments at the Advanced Test Reactor, including the effect of a release of fission products into the cladding-capsule gap. The computational results for these two cases were obtained using BISON, a fuel performance code under development at Idaho National Laboratory.

  10. Aviation fuels outlook

    NASA Technical Reports Server (NTRS)

    Momenthy, A. M.

    1980-01-01

    Options for satisfying the future demand for commercial jet fuels are analyzed. It is concluded that the most effective means to this end are to attract more refiners to the jet fuel market and encourage development of processes to convert oil shale and coal to transportation fuels. Furthermore, changing the U.S. refineries fuel specification would not significantly alter jet fuel availability.

  11. Methanol fuel mixture

    SciTech Connect

    Thrasher, D.A.; Greiner, L.; Cooper, G.

    1990-06-12

    This patent describes a fuel composition. It comprises: a major portion of fuel comprising 85 to 95% by volume of methanol; demineralized water, from 3 to 15% of the fuel; a fluorosurfactant for increasing the lubricity of the fuel, comprising approximately 0.01 to 0.05 weight percent of the fuel.

  12. Fuel Burn Estimation Model

    NASA Technical Reports Server (NTRS)

    Chatterji, Gano

    2011-01-01

    Conclusions: Validated the fuel estimation procedure using flight test data. A good fuel model can be created if weight and fuel data are available. Error in assumed takeoff weight results in similar amount of error in the fuel estimate. Fuel estimation error bounds can be determined.

  13. 146. FUEL LINE TO SKID 2 (FUEL LOADER) IN FUEL ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    146. FUEL LINE TO SKID 2 (FUEL LOADER) IN FUEL CONTROL ROOM (215), LSB (BLDG. 751). LIQUID NITROGEN/HELIUM HEAT EXCHANGER ON RIGHT. - Vandenberg Air Force Base, Space Launch Complex 3, Launch Pad 3 East, Napa & Alden Roads, Lompoc, Santa Barbara County, CA

  14. Fuel cell systems for personal and portable power applications

    SciTech Connect

    Fateen, S. A.

    2001-01-01

    Fuel cells are devices that electrochemically convert fuel, usually hydrogen gas, to directly produce electricity. Fuel cells were initially developed for use in the space program to provide electricity and drinking water for astronauts. Fuel cells are under development for use in the automobile industry to power cars and buses with the advantage of lower emissions and higher efficiency than internal combustion engines. Fuel cells also have great potential to be used in portable consumer products like cellular phones and laptop computers, as well as military applications. In fact, any products that use batteries can be powered by fuel cells. In this project, we examine fuel cell system trade-offs between fuel cell type and energy storage/hydrogen production for portable power generation. The types of fuel cells being examined include stored hydrogen PEM (polymer electrolyte), direct methanol fuel cells (DMFC) and indirect methanol fuel cells, where methanol is reformed producing hydrogen. These fuel cells systems can operate at or near ambient conditions, which make them potentially optimal for use in manned personal power applications. The expected power production for these systems is in the range of milliwatts to 500 watts of electrical power for either personal or soldier field use. The fuel cell system trade-offs examine hydrogen storage by metal hydrides, carbon nanotubes, and compressed hydrogen tanks. We examine the weights each system, volume, fuel storage, system costs, system peripherals, power output, and fuel cell feasibility in portable devices.

  15. Fuel extender

    SciTech Connect

    Dorn, G.K.; Gilbert, H.A.

    1989-02-21

    An efficient and cost competitive fuel extender liquid is described for blending with lead-free gasoline as an additive thereto in a maximum amount of up to about 35% thereof with 65% by volume of the gasoline in a blended mixture wherein. The content of the extender in the resultant fuel as proportioned on the basis of its thus representative maximum content consists essentially of: naphtha X as represented by C/sub 4/, C/sub 5/ and C/sub 6/ hydrocarbons having a Reid vapor pressure of about 8.5 to 9.6 per ASTM, D323 test procedure and an initial distillation point of about 101/sup 0/F. and an end point of about 280/sup 0/F. within a range of about 10 to 25% by volume, about 3.8 to 6.0% by volume of anhydrous ethanol, a stabilizing amount of a water repellent of the class consisting of ethyl acetate and methyl isotubyl ketone; and about 4 to 10.5% by volume of aromatics benzene and toluene, of benzene and xylene or of benzene with toluene and xylene; the extender having a specific gravity substantially comparable with that of the lead-free gasoline to which it is to be added and having phase stability in the presence of water when mixed with the gasoline.

  16. Renewable Fuel Standard Program

    EPA Pesticide Factsheets

    Information about regulations, developed by EPA, in collaboration with refiners, renewable fuel producers, and many other stakeholders, that ensure that transportation fuel sold in the United States contains a minimum volume of renewable fuel.

  17. Fuel cells: A survey

    NASA Technical Reports Server (NTRS)

    Crowe, B. J.

    1973-01-01

    A survey of fuel cell technology and applications is presented. The operating principles, performance capabilities, and limitations of fuel cells are discussed. Diagrams of fuel cell construction and operating characteristics are provided. Photographs of typical installations are included.

  18. Semi-analytical proton exchange membrane fuel cell modeling

    NASA Astrophysics Data System (ADS)

    Cheddie, Denver F.; Munroe, Norman D. H.

    Mathematical techniques are presented which allow for analytical solutions of the catalyst layer transport and electrochemical problem in PEM fuel cells. These techniques transform the volumetric reaction terms to boundary flux terms, thereby eliminating the need for computational solving of the catalyst layer problem. The result is a semi-analytical fuel cell model-a computational model that entails analytical rather than computational catalyst layer solutions. This helps to alleviate the meshing difficulties inherent in the catalyst layers caused by large geometric aspect ratios, and hence reduce the computational requirements for fuel cell models. These analytical solutions are implemented in a 3D PEM fuel cell model, and the results of the semi-analytical model match well with the full computational model in terms of the polarization performance and species concentration distribution. In addition, these analytical solutions were able to reduce the required computational memory by a factor of approximately 3, and the computational time by a factor of approximately 4.

  19. Future aviation fuels overview

    NASA Technical Reports Server (NTRS)

    Reck, G. M.

    1980-01-01

    The outlook for aviation fuels through the turn of the century is briefly discussed and the general objectives of the NASA Lewis Alternative Aviation Fuels Research Project are outlined. The NASA program involves the evaluation of potential characteristics of future jet aircraft fuels, the determination of the effects of those fuels on engine and fuel system components, and the development of a component technology to use those fuels.

  20. An Integrated Used Fuel Disposition and Generic Repository Model for Fuel Cycle Analysis

    NASA Astrophysics Data System (ADS)

    Huff, Kathryn D.

    As the United States and other nuclear nations consider alternative fuel cycles and waste disposal options simultaneously, an integrated fuel cycle and generic disposal system analysis tool grows increasingly necessary for informing spent nuclear fuel management policy. The long term performance characteristics of deep geologic disposal concepts are affected by heat and radionuclide release characteristics sensitive to disposal system choices as well as variable spent fuel compositions associated with alternative fuel cycles. Computational tools capable of simulating the dynamic, heterogeneous spent fuel isotopics resulting from alternative nuclear fuel cycles and fuel cycle transition scenarios are, however, lacking in disposal system modeling options. This work has resulted in Cyder, a generic repository software library appropriate for system analysis of potential future fuel cycle deployment scenarios. By emphasizing modularity and speed, Cyder is capable of representing the dominant physics of candidate geologic host media, repository designs, and engineering components. Robust and flexible integration with the Cyclus fuel cycle simulator enables this analysis in the context of fuel cycle options.

  1. Stationary Liquid Fuel Fast Reactor

    SciTech Connect

    Yang, Won Sik; Grandy, Andrew; Boroski, Andrew; Krajtl, Lubomir; Johnson, Terry

    2015-09-30

    For effective burning of hazardous transuranic (TRU) elements of used nuclear fuel, a transformational advanced reactor concept named SLFFR (Stationary Liquid Fuel Fast Reactor) was proposed based on stationary molten metallic fuel. The fuel enters the reactor vessel in a solid form, and then it is heated to molten temperature in a small melting heater. The fuel is contained within a closed, thick container with penetrating coolant channels, and thus it is not mixed with coolant nor flow through the primary heat transfer circuit. The makeup fuel is semi- continuously added to the system, and thus a very small excess reactivity is required. Gaseous fission products are also removed continuously, and a fraction of the fuel is periodically drawn off from the fuel container to a processing facility where non-gaseous mixed fission products and other impurities are removed and then the cleaned fuel is recycled into the fuel container. A reference core design and a preliminary plant system design of a 1000 MWt TRU- burning SLFFR concept were developed using TRU-Ce-Co fuel, Ta-10W fuel container, and sodium coolant. Conservative design approaches were adopted to stay within the current material performance database. Detailed neutronics and thermal-fluidic analyses were performed to develop a reference core design. Region-dependent 33-group cross sections were generated based on the ENDF/B-VII.0 data using the MC2-3 code. Core and fuel cycle analyses were performed in theta-r-z geometries using the DIF3D and REBUS-3 codes. Reactivity coefficients and kinetics parameters were calculated using the VARI3D perturbation theory code. Thermo-fluidic analyses were performed using the ANSYS FLUENT computational fluid dynamics (CFD) code. Figure 0.1 shows a schematic radial layout of the reference 1000 MWt SLFFR core, and Table 0.1 summarizes the main design parameters of SLFFR-1000 loop plant. The fuel container is a 2.5 cm thick cylinder with an inner radius of 87.5 cm. The fuel

  2. Post-crash fuel dispersal

    SciTech Connect

    Tieszen, S.R.

    1997-03-01

    This paper is a brief overview of work over the last several decades in understanding what occurs to jet fuel stored in aircraft fuel tanks on impact with the ground. Fuel dispersal is discussed in terms of the overall crash dynamics process and impact regimes are identified. In a generic sense, the types of flow regimes which can occur are identified and general descriptions of the processes are given. Examples of engineering level tools, both computational and experimental, which have applicability to analyzing the complex environments are presented. Finally, risk based decision is discussed as a quick means of identifying requirements for development of preventative or mitigation strategies, such as further work on the development of an anti-misting agent.

  3. Fuel processor for fuel cell power system

    DOEpatents

    Vanderborgh, Nicholas E.; Springer, Thomas E.; Huff, James R.

    1987-01-01

    A catalytic organic fuel processing apparatus, which can be used in a fuel cell power system, contains within a housing a catalyst chamber, a variable speed fan, and a combustion chamber. Vaporized organic fuel is circulated by the fan past the combustion chamber with which it is in indirect heat exchange relationship. The heated vaporized organic fuel enters a catalyst bed where it is converted into a desired product such as hydrogen needed to power the fuel cell. During periods of high demand, air is injected upstream of the combustion chamber and organic fuel injection means to burn with some of the organic fuel on the outside of the combustion chamber, and thus be in direct heat exchange relation with the organic fuel going into the catalyst bed.

  4. Fuel cell technology: A sweeter fuel

    NASA Astrophysics Data System (ADS)

    Kendall, Kevin

    2002-12-01

    Eating sugar gives us a boost when we feel tired because our cells use it as fuel to produce energy. Likewise, sugar can now be used to produce power in artificial biological fuel cells that function in a physiological environment.

  5. Effect of hydrocarbon fuel type on fuel

    NASA Technical Reports Server (NTRS)

    Wong, E. L.; Bittker, D. A.

    1982-01-01

    A modified jet fuel thermal oxidation tester (JFTOT) procedure was used to evaluate deposit and sediment formation for four pure hydrocarbon fuels over the temperature range 150 to 450 C in 316-stainless-steel heater tubes. Fuel types were a normal alkane, an alkene, a naphthene, and an aromatic. Each fuel exhibited certain distinctive deposit and sediment formation characteristics. The effect of aluminum and 316-stainless-steel heater tube surfaces on deposit formation for the fuel n-decane over the same temperature range was investigated. Results showed that an aluminum surface had lower deposit formation rates at all temperatures investigated. By using a modified JFTOT procedure the thermal stability of four pure hydrocarbon fuels and two practical fuels (Jet A and home heating oil no. 2) was rated on the basis of their breakpoint temperatures. Results indicate that this method could be used to rate thermal stability for a series of fuels.

  6. Fuel Reformer Nozzle Development

    NASA Technical Reports Server (NTRS)

    Lai, Ming-Chia D.

    2003-01-01

    The fellowship work this summer will be in support of the development of a fuel mixer for a liquid fuel reformer that is upstream of a fuel cell. Tasks for the summer shall consist of design of a fuel mixer, setup of the laser diagnostics for determining the degree of fuel mixing, and testing of the fuel mixer. The fuel mixer shall be a venturi section with fuel injected at or near the throat, and an air swirler upstream of the venturi. Data to determine the performance of the mixer shall be taken using a Phase Doppler Particle Analyzer (PDPA).

  7. Fuel Reformer Nozzle Development

    NASA Technical Reports Server (NTRS)

    Lai, Ming-Chia D.

    2003-01-01

    The fellowship work this summer will be in support of the development of a fuel mixer for a liquid fuel reformer that is upstream of a fuel cell. Tasks for the summer shall consist of design of a fuel mixer, setup of the laser diagnostics for determining the degree of fuel mixing, and testing of the fuel mixer. The fuel mixer shall be a venturi section with fuel injected at or near the throat, and an air swirler upstream of the venturi. Data to determine the performance of the mixer shall be taken using a Phase Doppler Particle Analyzer (PDPA).

  8. Internal reforming fuel cell assembly with simplified fuel feed

    DOEpatents

    Farooque, Mohammad; Novacco, Lawrence J.; Allen, Jeffrey P.

    2001-01-01

    A fuel cell assembly in which fuel cells adapted to internally reform fuel and fuel reformers for reforming fuel are arranged in a fuel cell stack. The fuel inlet ports of the fuel cells and the fuel inlet ports and reformed fuel outlet ports of the fuel reformers are arranged on one face of the fuel cell stack. A manifold sealing encloses this face of the stack and a reformer fuel delivery system is arranged entirely within the region between the manifold and the one face of the stack. The fuel reformer has a foil wrapping and a cover member forming with the foil wrapping an enclosed structure.

  9. EXFILE: A program for compiling irradiation data on UN and UC fuel pins

    NASA Technical Reports Server (NTRS)

    Mayer, J. T.; Smith, R. L.; Weinstein, M. B.; Davison, H. W.

    1973-01-01

    A FORTRAN-4 computer program for handling fuel pin data is described. Its main features include standardized output, easy access for data manipulation, and tabulation of important material property data. An additional feature allows simplified preparation of input decks for a fuel swelling computer code (CYGRO-2). Data from over 300 high temperature nitride and carbide based fuel pin irradiations are listed.

  10. NUCLEAR REACTOR FUEL-BREEDER FUEL ELEMENT

    DOEpatents

    Currier, E.L. Jr.; Nicklas, J.H.

    1962-08-14

    A fuel-breeder fuel element was developed for a nuclear reactor wherein discrete particles of fissionable material are dispersed in a matrix of fertile breeder material. The fuel element combines the advantages of a dispersion type and a breeder-type. (AEC)

  11. Fuel cells for low power applications

    NASA Astrophysics Data System (ADS)

    Heinzel, A.; Hebling, C.; Müller, M.; Zedda, M.; Müller, C.

    Electronic devices show an ever-increasing power demand and thus, require innovative concepts for power supply. For a wide range of power and energy capacity, membrane fuel cells are an attractive alternative to conventional batteries. The main advantages are the flexibility with respect to power and capacity achievable with different devices for energy conversion and energy storage, the long lifetime and long service life, the good ecological balance, very low self-discharge. Therefore, the development of fuel cell systems for portable electronic devices is an attractive, although also a challenging, goal. The fuel for a membrane fuel cell might be hydrogen from a hydride storage system or methanol/water as a liquid alternative. The main differences between the two systems are the much higher power density for hydrogen fuel cells, the higher energy density per weight for the liquid fuel, safety aspects and infrastructure for fuel supply for hydride materials. For different applications, different system designs are required. High power cells are required for portable computers, low power methanol fuel cells required for mobile phones in hybrid systems with batteries and micro-fuel cells are required, e.g. for hand held PCs in the sub-Watt range. All these technologies are currently under development. Performance data and results of simulations and experimental investigations will be presented.

  12. Cost targets for domestic fuel cell CHP

    NASA Astrophysics Data System (ADS)

    Staffell, I.; Green, R.; Kendall, K.

    Fuel cells have the potential to reduce domestic energy bills by providing both heat and power at the point of use, generating high value electricity from a low cost fuel. However, the cost of installing the fuel cell must be sufficiently low to be recovered by the savings made over its lifetime. A computer simulation is used to estimate the savings and cost targets for fuel cell CHP systems. Two pitfalls of this kind of simulation are addressed: the selection of representative performance figures for fuel cells, and the range of houses from which energy demand data was taken. A meta-study of the current state of the art is presented, and used with 102 house-years of demand to simulate the range of economic performance expected from four fuel cell technologies within the UK domestic CHP market. Annual savings relative to a condensing boiler are estimated at €170-300 for a 1 kWe fuel cell, giving a target cost of €350-625 kW -1 for any fuel cell technology that can demonstrate a 2.5-year lifetime. Increasing lifetime and reducing fuel cell capacity are identified as routes to accelerated market entry. The importance of energy demand is seen to outweigh both economic and technical performance assumptions, while manufacture cost and system lifetime are highlighted as the only significant differences between the technologies considered. SOFC are considered to have the greatest potential, but uncertainty in the assumptions used precludes any clear-cut judgement.

  13. Characteristics of spent nuclear fuel

    SciTech Connect

    Notz, K.J.

    1988-04-01

    The Office of Civilian Radioactive Waste Management (OCRWM) is responsible for the spent fuels and other wastes that will, or may, eventually be disposed of in a geological repository. The two major sources of these materials are commercial light-water reactor (LWR) spent fuel and immobilized high-level waste (HLW). Other wastes that may require long-term isolation include non-LWR spent fuels and miscellaneous sources such as activated metals. This report deals with spent fuels, but for completeness, the other sources are described briefly. Detailed characterizations are required for all of these potential repository wastes. These characteristics include physical, chemical, and radiological properties. The latter must take into account decay as a function of time. In addition, the present inventories and projected quantities of the various wastes are needed. This information has been assembled in a Characteristics Data Base which provides data in four formats: hard copy standard reports, menu-driven personal computer (PC) data bases, program-level PC data bases, and mainframe computer files. 5 refs., 3 figs., 4 tabs.

  14. Research on development of equations for performance trajectory computation

    NASA Technical Reports Server (NTRS)

    Harmon, G. R.

    1974-01-01

    A computer program for computing the performance trajectory of spacecraft was developed. An analytical study of a minimum fuel flight for high speed aircraft was conducted. The computer program to compute a minimum time reentry into the atmosphere for an Apollo-type capsule is presented. A technical summary of the minimum fuel problem is provided.

  15. Fuel dissipater for pressurized fuel cell generators

    DOEpatents

    Basel, Richard A.; King, John E.

    2003-11-04

    An apparatus and method are disclosed for eliminating the chemical energy of fuel remaining in a pressurized fuel cell generator (10) when the electrical power output of the fuel cell generator is terminated during transient operation, such as a shutdown; where, two electrically resistive elements (two of 28, 53, 54, 55) at least one of which is connected in parallel, in association with contactors (26, 57, 58, 59), a multi-point settable sensor relay (23) and a circuit breaker (24), are automatically connected across the fuel cell generator terminals (21, 22) at two or more contact points, in order to draw current, thereby depleting the fuel inventory in the generator.

  16. 40 CFR 80.8 - Sampling methods for gasoline, diesel fuel, fuel additives, and renewable fuels.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... fuel, fuel additives, and renewable fuels. 80.8 Section 80.8 Protection of Environment ENVIRONMENTAL... Provisions § 80.8 Sampling methods for gasoline, diesel fuel, fuel additives, and renewable fuels. The..., blendstocks, fuel additives and renewable fuels for purposes of determining compliance with the...

  17. Interim report spent nuclear fuel retrieval system fuel handling development testing

    SciTech Connect

    Ketner, G.L.; Meeuwsen, P.V.; Potter, J.D.; Smalley, J.T.; Baker, C.P.; Jaquish, W.R.

    1997-06-01

    Fuel handling development testing was performed in support of the Fuel Retrieval System (FRS) Sub-Project at the Hanford Site. The project will retrieve spent nuclear fuel, clean and remove fuel from canisters, repackage fuel into baskets, and load fuel into a multi-canister overpack (MCO) for vacuum drying and interim dry storage. The FRS is required to retrieve basin fuel canisters, clean fuel elements sufficiently of uranium corrosion products (or sludge), empty fuel from canisters, sort debris and scrap from whole elements, and repackage fuel in baskets in preparation for MCO loading. The purpose of fuel handling development testing was to examine the systems ability to accomplish mission activities, optimization of equipment layouts for initial process definition, identification of special needs/tools, verification of required design changes to support performance specification development, and validation of estimated activity times/throughput. The test program was set up to accomplish this purpose through cold development testing using simulated and prototype equipment; cold demonstration testing using vendor expertise and systems; and graphical computer modeling to confirm feasibility and throughput. To test the fuel handling process, a test mockup that represented the process table was fabricated and installed. The test mockup included a Schilling HV series manipulator that was prototypic of the Schilling Hydra manipulator. The process table mockup included the tipping station, sorting area, disassembly and inspection zones, fuel staging areas, and basket loading stations. The test results clearly indicate that the Schilling Hydra arm cannot effectively perform the fuel handling tasks required unless it is attached to some device that can impart vertical translation, azimuth rotation, and X-Y translation. Other test results indicate the importance of camera locations and capabilities, and of the jaw and end effector tool design. 5 refs., 35 figs., 3 tabs.

  18. Computer Calculation of Fire Danger

    Treesearch

    William A. Main

    1969-01-01

    This paper describes a computer program that calculates National Fire Danger Rating Indexes. fuel moisture, buildup index, and drying factor are also available. The program is written in FORTRAN and is usable on even the smallest compiler.

  19. Fuel injector and fuel injection system

    SciTech Connect

    Igashira, T.; Sakakibara, Y.; Yoshinaga, T.; Watanabe, K.; Takigawa, M.; Natsuyama, Y.; Daido, S.

    1988-11-15

    This patent describes a fuel injector comprising; a housing having formed therein a fuel pressure control chamber and an accumulator, which temporarily retain fuel, a path leading into the fuel pressure control chamber and accumulator, so that they receive which is intermitently fed under pressure from a fuel source through the path, and formed with a nozzle hold through which fuel in the accumulator is injected; a piezo actuator accommodated in the housing, defining the fuel pressure control chamber and expanding and contracting in accordance with a voltage applied thereto to change the volume of the fuel pressure control chamber; needle valve, of a type which opens and closes a responsive to an applied pressure, provided reciprocally movable within the housing between the accumulator and the nozzle hold and which, responsive to a pressure from the fuel pressure control chamber an accumulator, opens and closes communication between the accumulator and the nozzle hold; check valve means for normally closing communication between the path and the fuel pressure control chamber and between the path and the accumulator and for opening the communication according to pressure in the path and/or in the fuel pressure control chamber; and an electric circuit which controls a voltage applied to the piezo-actuator.

  20. Fuel cell status, 1994

    NASA Astrophysics Data System (ADS)

    Hirschenhofer, John H.

    1994-11-01

    Fuel cells are increasingly being used for commercial purposes in various countries worldwide because of their high efficiency environmental benefits. Among the nations which are pioneering the use of fuel cells are Australia, the United States, England, Japan, Germany, Netherlands, Belgium and Canada. These countries use fuel cells to augment the capacity of and improve the reliability of power plants fueled by natural gas.

  1. FUEL ROD CLUSTERS

    DOEpatents

    Schultz, A.B.

    1959-08-01

    A cluster of nuclear fuel rods and a tubular casing therefor through which a coolant flows in heat-exchange contact with the fuel rods is described. The fuel rcds are held in the casing by virtue of the compressive force exerted between longitudinal ribs of the fuel rcds and internal ribs of the casing or the internal surfaces thereof.

  2. Multipoint Fuel Injection Arrangements

    NASA Technical Reports Server (NTRS)

    Prociw, Lev Alexander (Inventor)

    2017-01-01

    A multipoint fuel injection system includes a plurality of fuel manifolds. Each manifold is in fluid communication with a plurality of injectors arranged circumferentially about a longitudinal axis for multipoint fuel injection. The injectors of separate respective manifolds are spaced radially apart from one another for separate radial staging of fuel flow to each respective manifold.

  3. Wood fuel preparation

    Treesearch

    L. H. Reineke

    1965-01-01

    This report gives information on the preparation of wood fuel from wood residues and other wood raw materials. Types of wood fuel discussed are cordwood, stovewood, slabwood, kindling, chips, hogged fuel, sawdust and shavings, bark, charcoal, alcohol, and briquets. Related information is given on types of machinery for preparing wood fuel and on possible markets for...

  4. Combustion Characterization and Model Fuel Development for Micro-tubular Flame-assisted Fuel Cells.

    PubMed

    Milcarek, Ryan J; Garrett, Michael J; Baskaran, Amrish; Ahn, Jeongmin

    2016-10-02

    Combustion based power generation has been accomplished for many years through a number of heat engine systems. Recently, a move towards small scale power generation and micro combustion as well as development in fuel cell research has created new means of power generation that combine solid oxide fuel cells with open flames and combustion exhaust. Instead of relying upon the heat of combustion, these solid oxide fuel cell systems rely on reforming of the fuel via combustion to generate syngas for electrochemical power generation. Procedures were developed to assess the combustion by-products under a wide range of conditions. While theoretical and computational procedures have been developed for assessing fuel-rich combustion exhaust in these applications, experimental techniques have also emerged. The experimental procedures often rely upon a gas chromatograph or mass spectrometer analysis of the flame and exhaust to assess the combustion process as a fuel reformer and means of heat generation. The experimental techniques developed in these areas have been applied anew for the development of the micro-tubular flame-assisted fuel cell. The protocol discussed in this work builds on past techniques to specify a procedure for characterizing fuel-rich combustion exhaust and developing a model fuel-rich combustion exhaust for use in flame-assisted fuel cell testing. The development of the procedure and its applications and limitations are discussed.

  5. Concentric layer ramjet fuel

    SciTech Connect

    Burdette, G.W.; Francis, J.P.

    1988-03-08

    This patent describes a solid fuel ramjet grain comprising concentric layers of solid ramjet fuel having a perforation therethrough along the center axis of the grain. The performation is connected to a combustion after-chamber. The solid ramjet fuel layers comprises a pure hydroxyl-terminated polybutadiene hydrocarbon fuel or a mixture of a hydroxyl-terminated polybutadiene hydrocarbon fuel and from about 5 to about 60 percent by weight of an additive to increase the fuel regression rate selected from the group consisting of magnesium, boron carbide, aluminum, and zirconium such that, when buried in the operation of the ramjet, each fuel layer produces a different level of thrust.

  6. Fuel cells seminar

    SciTech Connect

    1996-12-01

    This year`s meeting highlights the fact that fuel cells for both stationary and transportation applications have reached the dawn of commercialization. Sales of stationary fuel cells have grown steadily over the past 2 years. Phosphoric acid fuel cell buses have been demonstrated in urban areas. Proton-exchange membrane fuel cells are on the verge of revolutionizing the transportation industry. These activities and many more are discussed during this seminar, which provides a forum for people from the international fuel cell community engaged in a wide spectrum of fuel cell activities. Discussions addressing R&D of fuel cell technologies, manufacturing and marketing of fuel cells, and experiences of fuel cell users took place through oral and poster presentations. For the first time, the seminar included commercial exhibits, further evidence that commercial fuel cell technology has arrived. A total of 205 papers is included in this volume.

  7. Fuel transfer system

    DOEpatents

    Townsend, H.E.; Barbanti, G.

    1994-03-01

    A nuclear fuel bundle fuel transfer system includes a transfer pool containing water at a level above a reactor core. A fuel transfer machine therein includes a carriage disposed in the transfer pool and under the water for transporting fuel bundles. The carriage is selectively movable through the water in the transfer pool and individual fuel bundles are carried vertically in the carriage. In a preferred embodiment, a first movable bridge is disposed over an upper pool containing the reactor core, and a second movable bridge is disposed over a fuel storage pool, with the transfer pool being disposed therebetween. A fuel bundle may be moved by the first bridge from the reactor core and loaded into the carriage which transports the fuel bundle to the second bridge which picks up the fuel bundle and carries it to the fuel storage pool. 6 figures.

  8. Fuel transfer system

    DOEpatents

    Townsend, Harold E.; Barbanti, Giancarlo

    1994-01-01

    A nuclear fuel bundle fuel transfer system includes a transfer pool containing water at a level above a reactor core. A fuel transfer machine therein includes a carriage disposed in the transfer pool and under the water for transporting fuel bundles. The carriage is selectively movable through the water in the transfer pool and individual fuel bundles are carried vertically in the carriage. In a preferred embodiment, a first movable bridge is disposed over an upper pool containing the reactor core, and a second movable bridge is disposed over a fuel storage pool, with the transfer pool being disposed therebetween. A fuel bundle may be moved by the first bridge from the reactor core and loaded into the carriage which transports the fuel bundle to the second bridge which picks up the fuel bundle and carries it to the fuel storage pool.

  9. Mathematical modeling of solid oxide fuel cells

    NASA Technical Reports Server (NTRS)

    Lu, Cheng-Yi; Maloney, Thomas M.

    1988-01-01

    Development of predictive techniques, with regard to cell behavior, under various operating conditions is needed to improve cell performance, increase energy density, reduce manufacturing cost, and to broaden utilization of various fuels. Such technology would be especially beneficial for the solid oxide fuel cells (SOFC) at it early demonstration stage. The development of computer models to calculate the temperature, CD, reactant distributions in the tubular and monolithic SOFCs. Results indicate that problems of nonuniform heat generation and fuel gas depletion in the tubular cell module, and of size limitions in the monolithic (MOD 0) design may be encountered during FC operation.

  10. Fuel cells: principles, types, fuels, and applications.

    PubMed

    Carrette, L; Friedrich, K A; Stimming, U

    2000-12-15

    During the last decade, fuel cells have received enormous attention from research institutions and companies as novel electrical energy conversion systems. In the near future, they will see application in automotive propulsion, distributed power generation, and in low power portable devices (battery replacement). This review gives an introduction into the fundamentals and applications of fuel cells: Firstly, the environmental and social factors promoting fuel cell development are discussed, with an emphasis on the advantages of fuel cells compared to the conventional techniques. Then, the main reactions, which are responsible for the conversion of chemical into electrical energy in fuel cells, are given and the thermodynamic and kinetic fundamentals are stated. The theoretical and real efficiencies of fuel cells are also compared to that of internal combustion engines. Next, the different types of fuel cells and their main components are explained and the related material issues are presented. A section is devoted to fuel generation and storage, which is of paramount importance for the practical aspects of fuel cell use. Finally, attention is given to the integration of the fuel cells into complete systems. © 2000 WILEY-VCH Verlag GmbH, Weinheim, Fed. Rep. of Germany.

  11. Use of fluidic oscillator to measure fuel-air ratios of combustion gases

    NASA Technical Reports Server (NTRS)

    Riddlebaugh, S. M.

    1974-01-01

    A fluidic oscillator was investigated for use in measuring fuel-air ratios in hydrocarbon combustion processes. The oscillator was operated with dry exhaust gas from an experimental combustor burning ASTM A-1 fuel. Tests were conducted with fuel-air ratios between 0.015 and 0.031. Fuel-air ratios determined by oscillator frequency were within 0.001 of the values computed from separate flow measurements of the air and fuel.

  12. Market penetration scenarios for fuel cell vehicles

    SciTech Connect

    Thomas, C.E.; James, B.D.; Lomax, F.D. Jr.

    1997-12-31

    Fuel cell vehicles may create the first mass market for hydrogen as an energy carrier. Directed Technologies, Inc., working with the US Department of Energy hydrogen systems analysis team, has developed a time-dependent computer market penetration model. This model estimates the number of fuel cell vehicles that would be purchased over time as a function of their cost and the cost of hydrogen relative to the costs of competing vehicles and fuels. The model then calculates the return on investment for fuel cell vehicle manufacturers and hydrogen fuel suppliers. The model also projects the benefit/cost ratio for government--the ratio of societal benefits such as reduced oil consumption, reduced urban air pollution and reduced greenhouse gas emissions to the government cost for assisting the development of hydrogen energy and fuel cell vehicle technologies. The purpose of this model is to assist industry and government in choosing the best investment strategies to achieve significant return on investment and to maximize benefit/cost ratios. The model can illustrate trends and highlight the sensitivity of market penetration to various parameters such as fuel cell efficiency, cost, weight, and hydrogen cost. It can also illustrate the potential benefits of successful R and D and early demonstration projects. Results will be shown comparing the market penetration and return on investment estimates for direct hydrogen fuel cell vehicles compared to fuel cell vehicles with onboard fuel processors including methanol steam reformers and gasoline partial oxidation systems. Other alternative fueled vehicles including natural gas hybrids, direct injection diesels and hydrogen-powered internal combustion hybrid vehicles will also be analyzed.

  13. Multidimensional multiphysics simulation of nuclear fuel behavior

    NASA Astrophysics Data System (ADS)

    Williamson, R. L.; Hales, J. D.; Novascone, S. R.; Tonks, M. R.; Gaston, D. R.; Permann, C. J.; Andrs, D.; Martineau, R. C.

    2012-04-01

    Nuclear fuel operates in an environment that induces complex multiphysics phenomena, occurring over distances ranging from inter-atomic spacing to meters, and times scales ranging from microseconds to years. This multiphysics behavior is often tightly coupled and many important aspects are inherently multidimensional. Most current fuel modeling codes employ loose multiphysics coupling and are restricted to 2D axisymmetric or 1.5D approximations. This paper describes a new modeling tool able to simulate coupled multiphysics and multiscale fuel behavior, for either 2D axisymmetric or 3D geometries. Specific fuel analysis capabilities currently implemented in this tool are described, followed by a set of demonstration problems which include a 10-pellet light water reactor fuel rodlet, three-dimensional analysis of pellet clad mechanical interaction in the vicinity of a defective fuel pellet, coupled heat transfer and fission product diffusion in a TRISO-coated fuel particle, a demonstration of the ability to couple to lower-length scale models to account for material property variation with microstructural evolution, and a demonstration of the tool's ability to efficiently solve very large and complex problems using massively-parallel computing. A final section describes an early validation exercise, comparing simulation results to a light water reactor fuel rod experiment.

  14. Spent fuel pin temperature PC code

    SciTech Connect

    Fischer, L.E.

    1985-03-01

    During an annual outage, a Pressurized Water Reactor (PWR) may discharge 60 or more spent fuel bundles into its storage pool. Most early PWRs were built to store 3 to 5 years of spent fuel in their pools and are beginning to exceed their capacities. One method currently being developed and licensed for expanding spent fuel storage capabilities is the dry storage of spent fuel in large casks. To reduce the probability of gross failures of fuel cladding during dry storage in casks, the fuel pin temperatures must be shown to remain within acceptable limits. LLNL has developed, for the Nuclear Regulatory Commission, a personal computer (PC) code for calculating fuel pin temperatures on the IBM PC. The code uses the Wooton-Epstein Correlation to calculate the pin temperatures and has been benchmarked against test data. An iterative type of solution is used to calculate the fuel pin temperatures for specified heat fluxes and pin configurations. The PC code is useful in performing confirmatory analyses and comparing the results with those submitted by applicants applying for storage licenses. 5 references, 2 tables.

  15. Wavelets for ultrasonic echo identification in aircraft fuel tanks

    NASA Astrophysics Data System (ADS)

    Sadok, Mokhtar

    2002-03-01

    Recently, Goodrich Corp.- Fuels and Utility systems Division, has launched a research effort to investigate various sensing and computing techniques to gauge fuel in commercial and military aircrafts. Ultrasonics are among other techniques that were tested for such purpose. Generally, in ultrasonic fuel measurement systems, a transducer is excited to create sonic bursts into fuel and measure reflected echo off the fuel surface. A fixed target or pin is usually disposed at a fixed and predetermined distance from the ultrasonic transducer within the tank so as to compute the speed of sound through across fuel in the tank. Knowing the speed of sound in fuel and being able to measure the round trip time from when an ultrasonic burst is generated until its reflected off the fuel surface, the fuel height may be calculated. With a priori knowledge of the tank geometry, the fuel quantity can be estimated. This measurement process seems straightforward. A problem however is being able to discriminate between echoes reflected off various objects within the tank. In particular, it is crucial to discriminate among echoes reflected off various objects within the tank. In particular, it is crucial to discriminate among echoes reflected off the fuel surface and echoes reflected off other object withhin the tank, like the fixed target or tank sides. This paper presents a discrimination method based on wavelets to assign various ultrasonic echoes to their appropriate reflective surfaces.

  16. Fuel injector system

    DOEpatents

    Hsu, Bertrand D.; Leonard, Gary L.

    1988-01-01

    A fuel injection system particularly adapted for injecting coal slurry fuels at high pressures includes an accumulator-type fuel injector which utilizes high-pressure pilot fuel as a purging fluid to prevent hard particles in the fuel from impeding the opening and closing movement of a needle valve, and as a hydraulic medium to hold the needle valve in its closed position. A fluid passage in the injector delivers an appropriately small amount of the ignition-aiding pilot fuel to an appropriate region of a chamber in the injector's nozzle so that at the beginning of each injection interval the first stratum of fuel to be discharged consists essentially of pilot fuel and thereafter mostly slurry fuel is injected.

  17. Alternative aircraft fuels

    NASA Technical Reports Server (NTRS)

    Longwell, J. P.; Grobman, J.

    1978-01-01

    In connection with the anticipated impossibility to provide on a long-term basis liquid fuels derived from petroleum, an investigation has been conducted with the objective to assess the suitability of jet fuels made from oil shale and coal and to develop a data base which will allow optimization of future fuel characteristics, taking energy efficiency of manufacture and the tradeoffs in aircraft and engine design into account. The properties of future aviation fuels are examined and proposed solutions to problems of alternative fuels are discussed. Attention is given to the refining of jet fuel to current specifications, the control of fuel thermal stability, and combustor technology for use of broad specification fuels. The first solution is to continue to develop the necessary technology at the refinery to produce specification jet fuels regardless of the crude source.

  18. Alternative aircraft fuels

    NASA Technical Reports Server (NTRS)

    Longwell, J. P.; Grobman, J.

    1978-01-01

    In connection with the anticipated impossibility to provide on a long-term basis liquid fuels derived from petroleum, an investigation has been conducted with the objective to assess the suitability of jet fuels made from oil shale and coal and to develop a data base which will allow optimization of future fuel characteristics, taking energy efficiency of manufacture and the tradeoffs in aircraft and engine design into account. The properties of future aviation fuels are examined and proposed solutions to problems of alternative fuels are discussed. Attention is given to the refining of jet fuel to current specifications, the control of fuel thermal stability, and combustor technology for use of broad specification fuels. The first solution is to continue to develop the necessary technology at the refinery to produce specification jet fuels regardless of the crude source.

  19. Dual Tank Fuel System

    DOEpatents

    Wagner, Richard William; Burkhard, James Frank; Dauer, Kenneth John

    1999-11-16

    A dual tank fuel system has primary and secondary fuel tanks, with the primary tank including a filler pipe to receive fuel and a discharge line to deliver fuel to an engine, and with a balance pipe interconnecting the primary tank and the secondary tank. The balance pipe opens close to the bottom of each tank to direct fuel from the primary tank to the secondary tank as the primary tank is filled, and to direct fuel from the secondary tank to the primary tank as fuel is discharged from the primary tank through the discharge line. A vent line has branches connected to each tank to direct fuel vapor from the tanks as the tanks are filled, and to admit air to the tanks as fuel is delivered to the engine.

  20. Mapping wildland fuels for fire management across multiple scales: integrating remote sensing, GIS, and biophysical modeling

    USGS Publications Warehouse

    Keane, Robert E.; Burgan, Robert E.; Van Wagtendonk, Jan W.

    2001-01-01

    Fuel maps are essential for computing spatial fire hazard and risk and simulating fire growth and intensity across a landscape. However, fuel mapping is an extremely difficult and complex process requiring expertise in remotely sensed image classification, fire behavior, fuels modeling, ecology, and geographical information systems (GIS). This paper first presents the challenges of mapping fuels: canopy concealment, fuelbed complexity, fuel type diversity, fuel variability, and fuel model generalization. Then, four approaches to mapping fuels are discussed with examples provided from the literature: (1) field reconnaissance; (2) direct mapping methods; (3) indirect mapping methods; and (4) gradient modeling. A fuel mapping method is proposed that uses current remote sensing and image processing technology. Future fuel mapping needs are also discussed which include better field data and fuel models, accurate GIS reference layers, improved satellite imagery, and comprehensive ecosystem models.

  1. DIESEL FUEL LUBRICATION

    SciTech Connect

    Qu, Jun

    2012-01-01

    The diesel fuel injector and pump systems contain many sliding interfaces that rely for lubrication upon the fuels. The combination of the poor fuel lubricity and extremely tight geometric clearance between the plunger and bore makes the diesel fuel injector vulnerable to scuffing damage that severely limits the engine life. In order to meet the upcoming stricter diesel emission regulations and higher engine efficiency requirements, further fuel refinements that will result in even lower fuel lubricity due to the removal of essential lubricating compounds, more stringent operation conditions, and tighter geometric clearances are needed. These are expected to increase the scuffing and wear vulnerability of the diesel fuel injection and pump systems. In this chapter, two approaches are discussed to address this issue: (1) increasing fuel lubricity by introducing effective lubricity additives or alternative fuels, such as biodiesel, and (2) improving the fuel injector scuffing-resistance by using advanced materials and/or surface engineering processes. The developing status of the fuel modification approach is reviewed to cover topics including fuel lubricity origins, lubricity improvers, alternative fuels, and standard fuel lubricity tests. The discussion of the materials approach is focused on the methodology development for detection of the onset of scuffing and evaluation of the material scuffing characteristics.

  2. Novel proton exchange membrane fuel cell electrodes to improve performance of reversible fuel cell systems

    NASA Astrophysics Data System (ADS)

    Brown, Tim Matthew

    Proton exchange membrane (PEM) fuel cells react fuel and oxidant to directly and efficiently produce electrical power, without the need for combustion, heat engines, or motor-generators. Additionally, PEM fuel cell systems emit zero to virtually zero criteria pollutants and have the ability to reduce CO2 emissions due to their efficient operation, including the production or processing of fuel. A reversible fuel cell (RFC) is one particular application for a PEM fuel cell. In this application the fuel cell is coupled with an electrolyzer and a hydrogen storage tank to complete a system that can store and release electrical energy. These devices can be highly tailored to specific energy storage applications, potentially surpassing the performance of current and future secondary battery technology. Like all PEM applications, RFCs currently suffer from performance and cost limitations. One approach to address these limitations is to improve the cathode performance by engineering more optimal catalyst layer geometry as compared to the microscopically random structure traditionally used. Ideal configurations are examined and computer modeling shows promising performance improvements are possible. Several novel manufacturing methods are used to build and test small PEM fuel cells with novel electrodes. Additionally, a complete, dynamic model of an RFC system is constructed and the performance is simulated using both traditional and novel cathode structures. This work concludes that PEM fuel cell microstructures can be tailored to optimize performance based on design operating conditions. Computer modeling results indicate that novel electrode microstructures can improve fuel cell performance, while experimental results show similar performance gains that bolster the theoretical predictions. A dynamic system model predicts that novel PEM fuel cell electrode structures may enable RFC systems to be more competitive with traditional energy storage technology options.

  3. Fuel economy of hybrid fuel cell vehicles.

    SciTech Connect

    Ahluwalia, R.; Wang, X.; Rousseau, A.; Nuclear Engineering Division

    2004-01-01

    The potential improvement in fuel economy of a mid-size fuel-cell vehicle by combining it with an energy storage system has been assessed. An energy management strategy is developed and used to operate the direct hydrogen, pressurized fuel-cell system in a load-following mode and the energy storage system in a charge-sustaining mode. The strategy places highest priority on maintaining the energy storage system in a state where it can supply unanticipated boost power when the fuel-cell system alone cannot meet the power demand. It is found that downsizing a fuel-cell system decreases its efficiency on a drive cycle which is compensated by partial regenerative capture of braking energy. On a highway cycle with limited braking energy the increase in fuel economy with hybridization is small but on the stop-and-go urban cycle the fuel economy can improve by 27%. On the combined highway and urban drive cycles the fuel economy of the fuel-cell vehicle is estimated to increase by up to 15% by hybridizing it with an energy storage system.

  4. Fuel Flexible Combustion Systems for High-Efficiency Utilization of Opportunity Fuels in Gas Turbines

    SciTech Connect

    Venkatesan, Krishna

    2011-11-30

    provide experimental combustion data of our target fuels at gas turbine conditions. Based on an initial assessment of premixer design requirements and challenges, the most promising sub-scale premixer concepts were evaluated both experimentally and computationally. After comprehensive screening tests, two best performing concepts were scaled up for further development. High pressure single nozzle tests were performed with the scaled premixer concepts at target gas turbine conditions with opportunity fuels. Single-digit NOx emissions were demonstrated for syngas fuels. Plasma-assisted pilot technology was demonstrated to enhance ignition capability and provide additional flame stability margin to a standard premixing fuel nozzle. However, the impact of plasma on NOx emissions was observed to be unacceptable given the goals of this program and difficult to avoid.

  5. Small Volume Fuel Testers Report

    SciTech Connect

    Schoegl, I.; McNenly, M. J.; Killingsworth, N. J.

    2016-10-31

    Micro-liter fuel ignition testing (μ-FIT) is based on the premise that characteristics FREI (Flames with Repetitive Extinction and Ignition, i.e. cyclically occurring combustion events within heated capillaries), are linked to fuel properties. In early FY16, proof-of-concept measurements with primary reference fuel (PRF) mixtures, i.e. blends of n-heptane and iso-octane, yielded clear evidence for the feasibility of the approach. Our experiments showed that it is critical to accurately link observed flame positions to local temperatures, which provides information on ignition, extinction and flame propagation, all of which are known to be impacted by fuel properties. In FY16, one major hurdle was uncertainty of temperature calibration, which required significant efforts for corrective action that were not included in the original scope of work. Temperature calibrations are obtained by translating a thermocouple within the capillary in absence of a flame. While measurements have good repeatability when accounting for transient and insertion effects, results from nominally identical thermocouples reveal unacceptable uncertainty (up to ±50K), which is attributed to variations in thermocouple placement and manufacturing tolerances. This issue is currently being resolved by switching to non-intrusive optical temperature measurements. Updates are expected to yield uncertainties of less than ±10K, while also eliminating transient and insertion effects. The experimental work was complemented by computational efforts where it was shown that a simplified Lagrangian zero-D model with detailed kinetics yields fuelspecific differentiation of ignition temperatures for simple fuels that are consistent with experiments. Further, a 2D transient model was implemented in OpenFOAM to investigate combustion behavior of simple fuels at elevated pressure. In an upcoming visit to LLNL, more advanced simulations using LLNL’s computational tools (e.g. zero-RK) are planned, which will

  6. FUEL ELEMENT SUPPORT

    DOEpatents

    Wyman, W.L.

    1961-06-27

    The described cylindrical fuel element has longitudinally spaced sets of short longitudinal ribs circumferentially spaced from one another. The ribs support the fuel element in a coolant tube so that there is an annular space for coolant flow between the fuel element and the interior of the coolant tube. If the fuel element grows as a result of reactor operation, the circumferential distribution of the ribs maintains the uniformity of the annular space between the coolant tube and the fuel element, and the collapsibility of the ribs prevents the fuel element from becoming jammed in the coolant tube.

  7. Alternate Fuels Combustion Research

    DTIC Science & Technology

    1983-10-01

    of Temperature on Fuel Density ( ASTh D1298) 43 3.4 Effect of Temperature on Viscosity (ASTM D4AS) 44 3.5 Effect of Tcmperature on Surface Tension 45...Agencies 33 3.3 Fuel Distillation Range (AF.€ D86) 34 3.4 Fuel Distillation Range ( ASTh D2887) 35 3.5 Fuel Properties I 36 3.6 Fuel Properties II 37 3.7...the case of the less volatile fuels. - 29 - Freeze Point ASTh [2386 (QETE) Setapoint (NRC) ASTM D2386 (Figure 3.6) records the disappearance of the

  8. A MOX Fuel Attribute Monitor

    SciTech Connect

    Bliss, Mary; Jordan, David V.; Barnett, Debra S.; Redding, Rebecca L.; Pearce, Stephen K.

    2007-08-21

    Euratom performs safeguards monitoring of Fresh MOX fuel for domestic power production in the European Union. Video cameras monitor the reactor storage ponds. If video surveillance is lost for a certain amount of time a measurement is required to verify that no fuel was diverted. The attribute measurement to verify the continued presence of MOX fuel is neutron emission. Ideally this measurement would be made without moving or handling the fuel rod assembly. A prototype attribute measurement system was made using scintillating neutron sensitive glass waveguides developed by Pacific Northwest National Laboratory. Short lengths (5-20 cm) of the neutron sensitive fiber were mechanically spliced to 15 m lengths of commercial high numerical aperture fiber optic cable (Ceramoptec Optran Ultra 0.44). The light detector is a Hamamatsu R7400P photomultiplier tube. An electronics package was built to use the sensors with a GBS Elektronik MCA-166 multichannel analyzer and user interface. The MCA-166 is the system most commonly used by Euratom inspectors. It can also be run from a laptop computer using Maestro (Ortec) or other software. A MCNP model was made to compare to measurements made with several neutron sources including NIST traceable 252Cf.

  9. A MOX fuel attribute monitor

    NASA Astrophysics Data System (ADS)

    Bliss, Mary; Jordan, David V.; Barnett, Debra S.; Redding, Rebecca L.; Pearce, Stephen K.

    2007-08-01

    Euratom performs safeguards monitoring of Fresh MOX fuel for domestic power production in the European Union. Video cameras monitor the reactor storage ponds. If video surveillance is lost for a certain amount of time a measurement is required to verify that no fuel was diverted. The attribute measurement to verify the continued presence of MOX fuel is neutron emission. Ideally this measurement would be made without moving or handling the fuel rod assembly. A prototype attribute measurement system was made using scintillating neutron sensitive glass waveguides developed by Pacific Northwest National Laboratory. Short lengths (5-20 cm) of the neutron sensitive fiber were mechanically spliced to 15 m lengths of commercial high numerical aperture fiber optic cable (Ceramoptec Optran Ultra 0.44). The light detector is a Hamamatsu R7400P photomultiplier tube. An electronics package was built to use the sensors with a GBS Elektronik MCA-166 multichannel analyzer and user interface. The MCA-166 is the system most commonly used by Euratom inspectors. It can also be run from a laptop computer using Maestro (Ortec) or other software. A MCNP model was made to compare to measurements made with several neutron sources including NIST traceable 252Cf.

  10. Fuel injection nozzle

    SciTech Connect

    Kato, M.; Tojo, S.; Arai, K.

    1986-07-22

    A fuel injection nozzle is described connected to a fuel injection pump to inject fuel into a combustion chamber of an internal combustion engine consisting of: a nozzle housing defining therein a fuel sump chamber, an injection hole communicating with the sump chamber and opened at the outer surface of the nozzle housing, a stepped cylinder bore having a smaller diameter bore section and a larger diameter bore section and a fuel passage communicating at one end with the sump chamber and at the other end with the smaller diameter bore section of the stepped cylinder bore; a stepped plunger fitted in the stepped cylinder bore and having a smaller diameter plunger section fitted into the smaller diameter bore section and a larger diameter plunger section fitted into the larger diameter bore section in which the smaller diameter bore section together with the end face of the smaller diameter plunger section defines a pump chamber communicating with the fuel passage and the larger diameter bore section together with the end face of the larger diameter plunger section defines a main fuel chamber into which a main fuel is supplied from the fuel injection pump; auxiliary fuel supply means for supplying an auxiliary fuel into the sump chamber and pump chamber through the fuel passage; valve means for opening and closing an injection hole; communication means for permitting the main fuel chamber to communicate with the fuel passage when the main fuel is supplied from the injection pump into the main fuel chamber to cause the stepped plunger to be moved a predetermined distance in a direction in which the auxiliary fuel in the pump chamber is pressurized.

  11. Fuel injection system

    SciTech Connect

    Miyaki, M.; Iwanaga, T.; Fujisawa, H.

    1988-10-18

    This patent describes a fuel injection system for a diesel engine comprising: condition detection means for detecting operating conditions of the diesel engine including a rotational position thereof; low pressure fuel supply means for supplying fuel at a low pressure at an output port thereof; high pressure fuel pump means, having a pump chamber communicating with the output port of the low pressure fuel supply means, and plunger means reciprocable within the pump chamber for introducing fuel from the output port of the low pressure fuel supply means into the pump chamber during a movement in a predetermined direction of the plunger means and for pressurizing the introduced fuel during a movement of the plunger means in the opposite direction so that pressurized fuel is delivered from the high pressure fuel pump means at an output port thereof; common rail fuel storage means, connected to the output port of the high pressure fuel pump means, for storing pressurized fuel delivered from the high pressure pump therein at a substantially continuous pressure.

  12. Fuel injection pump

    SciTech Connect

    Miyaki, M.

    1986-01-07

    This patent describes a fuel injection pump for delivering fuel to the cylinders of an internal combustion engine consisting of: a pump housing with a fuel chamber therein to which fuel is supplied from a fuel tank; means for compressing fuel in the pump chamber and delivering the compressed fuel to the engine cylinders with such means including a pump plunger adapted to be reciprocated so as to introduce fuel into the pump chamber and to pressurize the introduced fuel; spill means for spilling to a low-pressure side on a fuel tank side the compressed fuel which was pressurized in the pump chamber to be delivered from the pump chamber to the engine cylinders, the spill mechanism including a spill passage communicating with the pump chamber and including a solenoid valve located in the spill passage for opening and closing the spill passage with predetermined timing; escape for allowing the compressed fuel pressurized in the pump chamber to escape to the low-pressure side of the fuel tank side.

  13. Thermal Analysis of ZPPR High Pu Content Stored Fuel

    DOE PAGES

    Solbrig, Charles W.; Pope, Chad L.; Andrus, Jason P.

    2014-09-17

    The Zero Power Physics Reactor (ZPPR) operated from April 18, 1969, until 1990. ZPPR operated at low power for testing nuclear reactor designs. This paper examines the temperature of Pu content ZPPR fuel while it is in storage. Heat is generated in the fuel due to Pu and Am decay and is a concern for possible cladding damage. Damage to the cladding could lead to fuel hydriding and oxidizing. A series of computer simulations were made to determine the range of temperatures potentially occuring in the ZPPR fuel. The maximum calculated fuel temperature is 292°C (558°F). Conservative assumptions in themore » model intentionally overestimate temperatures. The stored fuel temperatures are dependent on the distribution of fuel in the surrounding storage compartments, the heat generation rate of the fuel, and the orientation of fuel. Direct fuel temperatures could not be measured but storage bin doors, storage sleeve doors, and storage canister temperatures were measured. Comparison of these three temperatures to the calculations indicates that the temperatures calculated with conservative assumptions are, as expected, higher than the actual temperatures. The maximum calculated fuel temperature with the most conservative assumptions is significantly below the fuel failure criterion of 600°C (1,112°F).« less

  14. Fuel management studies of small metal and oxide LMR's

    SciTech Connect

    Khalil, H.; Fujita, E.K.; Yang, S.; Orechwa, Y.

    1986-01-01

    Fuel-cycle analyses performed at Argonne National Laboratory to evaluate and compare the neutronic performance characteristics of small oxide- and metal-fueled LMR's are described. Specific consideration is given to those analyses concerned with optimization of core and blanket configurations, selection of fuel residence time and refueling interval, determination of control rod worths and requirements, development of in-core fuel management strategy, and evaluation of performance characteristics both for startup cycles and for the equilibrium state reached via repeated recycle of discharged fuel. Differences in the computed performance parameters of oxide and metal cores, arising from basic differences in their neutronic characteristics, are identified and discussed. Metal-fueled cores are shown to offer some important performance advantages over oxide cores for small LMR's because of their harder spectrum, superior neutron economy, and greater breeding capacity. These advantages include smaller fissile and heavy metal loadings, lower control-system requirements, and greater adaptability to changes in fuel management scenarios.

  15. Fuels Combustion Research: Supercritical Fuel Pyrolysis

    DTIC Science & Technology

    2001-06-19

    and development of fuel systems for high-speed aircraft. AUTHORS: M. J. Womat. E. B. Ledesma , J. A. Sivo, and N. D. Marsh TECHNICAL DISCUSSION...aircraft. REFERENCES 1. Edwards, T., "USAF Supercritical Hydrocarbon Fuels Interests," AIAA Paper 93-0807 (1993). 2. Wornat, M. J., Ledesma , E. B

  16. Fuel cells and fuel cell catalysts

    DOEpatents

    Masel, Richard I.; Rice, Cynthia A.; Waszczuk, Piotr; Wieckowski, Andrzej

    2006-11-07

    A direct organic fuel cell includes a formic acid fuel solution having between about 10% and about 95% formic acid. The formic acid is oxidized at an anode. The anode may include a Pt/Pd catalyst that promotes the direct oxidation of the formic acid via a direct reaction path that does not include formation of a CO intermediate.

  17. Nuclear fuel element

    DOEpatents

    Zocher, Roy W.

    1991-01-01

    A nuclear fuel element and a method of manufacturing the element. The fuel element is comprised of a metal primary container and a fuel pellet which is located inside it and which is often fragmented. The primary container is subjected to elevated pressure and temperature to deform the container such that the container conforms to the fuel pellet, that is, such that the container is in substantial contact with the surface of the pellet. This conformance eliminates clearances which permit rubbing together of fuel pellet fragments and rubbing of fuel pellet fragments against the container, thus reducing the amount of dust inside the fuel container and the amount of dust which may escape in the event of container breach. Also, as a result of the inventive method, fuel pellet fragments tend to adhere to one another to form a coherent non-fragmented mass; this reduces the tendency of a fragment to pierce the container in the event of impact.

  18. Microscale Fuel Cells

    SciTech Connect

    Holladay, Jamie D.; Viswanathan, Vish V.

    2005-11-03

    Perhaprs some of the most innovative work on fuel cells has been the research dedicated to applying silicon fabrication techniques to fuel cells technology creating low power microscale fuel cells applicable to microelectro mechanical systems (MEMS), microsensors, cell phones, PDA’s, and other low power (0.001 to 5 We) applications. In this small power range, fuel cells offer the decoupling of the energy converter from the energy storage which may enable longer operating times and instant or near instant charging. To date, most of the microscale fuel cells being developed have been based on proton exchange membrane fuel cell technology (PEMFC) or direct methanol fuel cell (DMFC) technology. This section will discuss requirements and considerations that need to be addressed in the development of microscale fuel cells, as well as some proposed designs and fabrication strategies.

  19. Integrated fuel management system

    SciTech Connect

    Barbeau, D.E.

    1987-09-29

    An aircraft fuel management system to regulate fuel from an airframe reservoir is described. The system comprises: an aircraft turbine engine having a combustor providing propulsion for the aircraft; a fuel pump receiving fuel from the reservoir and supplying fuel to the turbine engine; a motor controlling the pump so as to provide fuel to the turbine engine; means for sensing at least one engine condition; means responsive to the sensing means for controlling fuel flow to the turbine engine, and wherein the pump and the motor are of the constant speed type and further comprising valve means for controlling the fuel flow rate to the turbine engine and wherein the controlling means modulates the position of the valve means.

  20. Alternative aircraft fuels technology

    NASA Technical Reports Server (NTRS)

    Grobman, J.

    1976-01-01

    NASA is studying the characteristics of future aircraft fuels produced from either petroleum or nonpetroleum sources such as oil shale or coal. These future hydrocarbon based fuels may have chemical and physical properties that are different from present aviation turbine fuels. This research is aimed at determining what those characteristics may be, how present aircraft and engine components and materials would be affected by fuel specification changes, and what changes in both aircraft and engine design would be required to utilize these future fuels without sacrificing performance, reliability, or safety. This fuels technology program was organized to include both in-house and contract research on the synthesis and characterization of fuels, component evaluations of combustors, turbines, and fuel systems, and, eventually, full-scale engine demonstrations. A review of the various elements of the program and significant results obtained so far are presented.

  1. Fuel quality combustion analysis

    NASA Technical Reports Server (NTRS)

    Naegeli, D. W.; Moses, C. A.

    1979-01-01

    A high pressure research combustor operating over a wide range of burner inlet conditions was used to determine the effects of fuel molecular structure on soot formation. Six test fuels with equal hydrogen content (12.8%) were blended to stress different molecular components and final boiling points. The fuels containing high concentrations (20%) of polycyclic aromatics and partially saturated polycyclic structures such as tetralin, produced more soot than would be expected from a hydrogen content correlation for typical petroleum based fuels. Fuels containing naphthenes such as decalin agreed with the hydrogen content correlation. The contribution of polycyclic aromatics to soot formation was equivalent to a reduction in fuel hydrogen content of about one percent. The fuel sensitivity to soot formation due to the polycyclic aromatic contribution decreased as burner inlet pressure and fuel/air ratio increased.

  2. FUEL CELL ELECTRODE MATERIALS

    DTIC Science & Technology

    FUEL CELL ELECTRODE MATERIALS. RAW MATERIAL SELECTION INFLUENCES POLARIZATION BUT IS NOT A SINGLE CONTROLLING FACTOR. AVAILABLE...DATA INDICATES THAT AN INTERRELATIONSHIP OF POROSITY, AVERAGE PORE VOLUME, AND PERMEABILITY CONTRIBUTES TO ELECTRODE FUEL CELL BEHAVIOR.

  3. Reformulated diesel fuel

    DOEpatents

    McAdams, Hiramie T [Carrollton, IL; Crawford, Robert W [Tucson, AZ; Hadder, Gerald R [Oak Ridge, TN; McNutt, Barry D [Arlington, VA

    2006-03-28

    Reformulated diesel fuels for automotive diesel engines which meet the requirements of ASTM 975-02 and provide significantly reduced emissions of nitrogen oxides (NO.sub.x) and particulate matter (PM) relative to commercially available diesel fuels.

  4. Fuel collecting and recycling system

    SciTech Connect

    Cole, E.F.

    1980-06-10

    This system serves to collect and recycle fuel leftover in the fuel manifold and fuel distribution system of a gas turbine power plant when it is shutdown and operates in conjunction with the power plant's existing fuel control.

  5. Miniature ceramic fuel cell

    DOEpatents

    Lessing, Paul A.; Zuppero, Anthony C.

    1997-06-24

    A miniature power source assembly capable of providing portable electricity is provided. A preferred embodiment of the power source assembly employing a fuel tank, fuel pump and control, air pump, heat management system, power chamber, power conditioning and power storage. The power chamber utilizes a ceramic fuel cell to produce the electricity. Incoming hydro carbon fuel is automatically reformed within the power chamber. Electrochemical combustion of hydrogen then produces electricity.

  6. FUEL ROD ASSEMBLY

    DOEpatents

    Hutter, E.

    1959-09-01

    A cluster of nuclear fuel rods aod a tubular casing through which a coolant flows in heat-change contact with the ruel rods are described. The casting is of trefoil section and carries the fuel rods, each of which has two fin engaging the serrated fins of the other two fuel rods, whereby the fuel rods are held in the casing and are interlocked against relative longitudinal movement.

  7. Alternative Fuels (Briefing Charts)

    DTIC Science & Technology

    2009-06-19

    feedstock for HRJ, plant cost for F-T) Courtesy AFRL, Dr. Tim Edwards Unclassified • Agricultural crop oils ( canola , jatropha, soy, palm, etc...dioxide emissions Security of crude oil questioned Qatar GTL Production * Fuels produced from seeds and other organic sources such as Soybean Methyl Ester...Fuels Focus  Various conversion processes  Upgraded to meet fuel specs Diverse energy sources Petroleum Crude Oil Petroleum based Single Fuel in the

  8. Fuels Reporting System Data

    EPA Pesticide Factsheets

    This asset includes compliance data (registrations and reports), including reports related to reformulated gasoline and conventional gasoline (anti-dumping), gasoline sulfur, mobile source air toxics (including gasoline benzene), sulfur content of on-road and non-road diesel fuel, and renewable fuels under 40 CFR Part 80; and includes registration and compositional information related to fuels and fuel additives under 40 CFR Part 79.

  9. Fuel cells feasibility

    NASA Technical Reports Server (NTRS)

    Schonfeld, D.; Charng, T.

    1981-01-01

    The technical and economic status of fuel cells is assessed with emphasis on their potential benefits to the Deep Space Network. The fuel cell, what it is, how it operates, and what its outputs are, is reviewed. Major technical problems of the fuel cell and its components are highlighted. Due to these problems and economic considerations it is concluded that fuel cells will not become commercially viable until the early 1990s.

  10. COMPOSITE FUEL ELEMENT

    DOEpatents

    Hurford, W.J.; Gordon, R.B.; Johnson, W.A.

    1962-12-25

    A sandwich-type fuel element for a reactor is described. This fuel element has the shape of an elongated flat plate and includes a filler plate having a plurality of compartments therein in which the fuel material is located. The filler plate is clad on both sides with a thin cladding material which is secured to the filler plate only to completely enclose the fuel material in each compartment. (AEC)

  11. Direct hydrocarbon fuel cells

    DOEpatents

    Barnett, Scott A.; Lai, Tammy; Liu, Jiang

    2010-05-04

    The direct electrochemical oxidation of hydrocarbons in solid oxide fuel cells, to generate greater power densities at lower temperatures without carbon deposition. The performance obtained is comparable to that of fuel cells used for hydrogen, and is achieved by using novel anode composites at low operating temperatures. Such solid oxide fuel cells, regardless of fuel source or operation, can be configured advantageously using the structural geometries of this invention.

  12. Transportation fuels from wood

    SciTech Connect

    Baker, E.G.; Elliott, D.C.; Stevens, D.J.

    1980-01-01

    The various methods of producing transportation fuels from wood are evaluated in this paper. These methods include direct liquefaction schemes such as hydrolysis/fermentation, pyrolysis, and thermochemical liquefaction. Indirect liquefaction techniques involve gasification followed by liquid fuels synthesis such as methanol synthesis or the Fischer-Tropsch synthesis. The cost of transportation fuels produced by the various methods are compared. In addition, three ongoing programs at Pacific Northwest Laboratory dealing with liquid fuels from wood are described.

  13. Navy Fuel Specification Standardization

    DTIC Science & Technology

    1992-04-01

    surfaced periodically to convert further to a single-fuel operation, i.e., one fuel for both aircraft and ship propulsion /power systems. This study...lead to the development of a single distillate fuel for ship propulsion , resulting eventually in the MIL-F-16884 Naval Distillate Fuel (NDF) used today...for both aircraft and ship propulsion /power systems. This report summarizes a study to consider this problem in light of current systems and

  14. Fakir fuel pump

    NASA Technical Reports Server (NTRS)

    1922-01-01

    In designing the Fakir fuel pump, the fundamental idea was to obtain a simple and reliable method of conveying the fuel from a low tank to the carburetor, with the avoidance of the faults of all former methods and the simultaneous warming of the fuel by means of the heat of compression generated. The principle of the Fakir fuel pump rests on the well-known principle of the diaphragm pump, which must be suitably adapted to the present purpose.

  15. Jet fuel instability mechanisms

    NASA Technical Reports Server (NTRS)

    Daniel, S. R.

    1985-01-01

    The mechanisms of the formation of fuel-insoluble deposits were studied in several real fuels and in a model fuel consisting of tetralin in dodecane solution. The influence of addition to the fuels of small concentrations of various compounds on the quantities of deposits formed and on the formation and disappearance of oxygenated species in solution was assessed. The effect of temperature on deposit formation was also investigated over the range of 308-453 K.

  16. Cell module and fuel conditioner

    NASA Technical Reports Server (NTRS)

    Hoover, D. Q., Jr.

    1980-01-01

    The computer code for the detailed analytical model of the MK-2 stacks is described. An ERC proprietary matrix is incorporated in the stacks. The mechanical behavior of the stack during thermal cycles under compression was determined. A 5 cell stack of the MK-2 design was fabricated and tested. Designs for the next three stacks were selected and component fabrication initiated. A 3 cell stack which verified the use of wet assembly and a new acid fill procedure were fabricated and tested. Components for the 2 kW test facility were received or fabricated and construction of the facility is underway. The definition of fuel and water is used in a study of the fuel conditioning subsystem. Kinetic data on several catalysts, both crushed and pellets, was obtained in the differential reactor. A preliminary definition of the equipment requirements for treating tap and recovered water was developed.

  17. Fireplaces and Fireplace Fuels.

    ERIC Educational Resources Information Center

    Metz, Ron

    This instructional unit is one of 10 developed by students on various energy-related areas that deals specifically with fireplaces and fuels. Its objective is for the student to be able to discuss the structural design, operation, and efficiency of fireplaces and characteristics of different fireplace fuels. Some topics covered are fuels, elements…

  18. Alternative Fuels Data Center

    SciTech Connect

    2013-06-01

    Fact sheet describes the Alternative Fuels Data Center, which provides information, data, and tools to help fleets and other transportation decision makers find ways to reduce petroleum consumption through the use of alternative and renewable fuels, advanced vehicles, and other fuel-saving measures.

  19. Vented nuclear fuel element

    DOEpatents

    Grossman, Leonard N.; Kaznoff, Alexis I.

    1979-01-01

    A nuclear fuel cell for use in a thermionic nuclear reactor in which a small conduit extends from the outside surface of the emitter to the center of the fuel mass of the emitter body to permit escape of volatile and gaseous fission products collected in the center thereof by virtue of molecular migration of the gases to the hotter region of the fuel.

  20. Fuel cell generator

    DOEpatents

    Isenberg, Arnold O.

    1983-01-01

    High temperature solid oxide electrolyte fuel cell generators which allow controlled leakage among plural chambers in a sealed housing. Depleted oxidant and fuel are directly reacted in one chamber to combust remaining fuel and preheat incoming reactants. The cells are preferably electrically arranged in a series-parallel configuration.

  1. Nuclear fuels status

    NASA Technical Reports Server (NTRS)

    Kania, Michael

    1991-01-01

    A discussion on coated particle fuel performance from a modular High Temperature Gas Reactor (HTGR) is presented along with experimental results. The following topics are covered: (1) the coated particle fuel concept; (2) the functional requirements; (3) performance limiting mechanisms; (4) fuel performance; and (5) methods/techniques for characterizing performance.

  2. Fuels from Recycling Systems

    ERIC Educational Resources Information Center

    Tillman, David A.

    1975-01-01

    Three systems, operating at sufficient scale, produce fuels that may be alternatives to oil and gas. These three recycling systems are: Black Clawson Fiberclaim, Franklin, Ohio; Union Carbide, South Charleston, West Virginia; and Union Electric, St. Louis, Missouri. These produce a wet fuel, a pyrolytic gas, and a dry fuel, respectively. (BT)

  3. Modeling fuel succession

    Treesearch

    Brett Davis; Jan van Wagtendonk; Jen Beck; Kent van Wagtendonk

    2009-01-01

    Surface fuels data are of critical importance for supporting fire incident management, risk assessment, and fuel management planning, but the development of surface fuels data can be expensive and time consuming. The data development process is extensive, generally beginning with acquisition of remotely sensed spatial data such as aerial photography or satellite...

  4. Fuels from Recycling Systems

    ERIC Educational Resources Information Center

    Tillman, David A.

    1975-01-01

    Three systems, operating at sufficient scale, produce fuels that may be alternatives to oil and gas. These three recycling systems are: Black Clawson Fiberclaim, Franklin, Ohio; Union Carbide, South Charleston, West Virginia; and Union Electric, St. Louis, Missouri. These produce a wet fuel, a pyrolytic gas, and a dry fuel, respectively. (BT)

  5. Fireplaces and Fireplace Fuels.

    ERIC Educational Resources Information Center

    Metz, Ron

    This instructional unit is one of 10 developed by students on various energy-related areas that deals specifically with fireplaces and fuels. Its objective is for the student to be able to discuss the structural design, operation, and efficiency of fireplaces and characteristics of different fireplace fuels. Some topics covered are fuels, elements…

  6. Vehicle fuel system

    DOEpatents

    Risse, John T.; Taggart, James C.

    1976-01-01

    A vehicle fuel system comprising a plurality of tanks, each tank having a feed and a return conduit extending into a lower portion thereof, the several feed conduits joined to form one supply conduit feeding fuel to a supply pump and using means, unused fuel being returned via a return conduit which branches off to the several return conduits.

  7. Metallic fuel development

    SciTech Connect

    Walters, L.C.

    1987-01-01

    Metallic fuels are capable of achieving high burnup as a result of design modifications instituted in the late 1960's. The gap between the fuel slug and the cladding is fixed such that by the time the fuel swells to the cladding the fission gas bubbles interconnect and release the fission gas to an appropriately sized plenum volume. Interconnected porosity thus provides room for the fuel to deform from further swelling rather than stress the cladding. In addition, the interconnected porosity allows the fuel pin to be tolerant to transient events because as stresses are generated during a transient event the fuel flows rather than applying significant stress to the cladding. Until 1969 a number of metallic fuel alloys were under development in the US. At that time the metallic fuel development program in the US was discontinued in favor of ceramic fuels. However, development had proceeded to the point where it was clear that the zirconium addition to uranium-plutonium fuel would yield a ternary fuel with an adequately high solidus temperature and good compatibility with austenitic stainless steel cladding. Furthermore, several U-Pu-Zr fuel pins had achieved about 6 at.% bu by the late 1960's, without failure, and thus the prospect for high burnup was promising.

  8. Rapid scanning system for fuel drawers

    DOEpatents

    Caldwell, John T.; Fehlau, Paul E.; France, Stephen W.

    1981-01-01

    A nondestructive method for uniqely distinguishing among and quantifying the mass of individual fuel plates in situ in fuel drawers utilized in nuclear reactors is described. The method is both rapid and passive, eliminating the personnel hazard of the commonly used irradiation techniques which require that the analysis be performed in proximity to an intense neutron source such as a reactor. In the present technique, only normally decaying nuclei are observed. This allows the analysis to be performed anywhere. This feature, combined with rapid scanning of a given fuel drawer (in approximately 30 s), and the computer data analysis allows the processing of large numbers of fuel drawers efficiently in the event of a loss alert.

  9. Rapid scanning system for fuel drawers

    DOEpatents

    Caldwell, J.T.; Fehlau, P.E.; France, S.W.

    A nondestructive method for uniquely distinguishing among and quantifying the mass of individual fuel plates in situ in fuel drawers utilized in nuclear reactors is described. The method is both rapid and passive, eliminating the personnel hazard of the commonly used irradiation techniques which require that the analysis be performed in proximity to an intense neutron source such as a reactor. In the present technique, only normally decaying nuclei are observed. This allows the analysis to be performed anywhere. This feature, combined with rapid scanning of a given fuel drawer (in approximately 30 s), and the computer data analysis allows the processing of large numbers of fuel drawers efficiently in the event of a loss alert.

  10. Multidimensional Multiphysics Simulation of TRISO Particle Fuel

    SciTech Connect

    J. D. Hales; R. L. Williamson; S. R. Novascone; D. M. Perez; B. W. Spencer; G. Pastore

    2013-11-01

    Multidimensional multiphysics analysis of TRISO-coated particle fuel using the BISON finite-element based nuclear fuels code is described. The governing equations and material models applicable to particle fuel and implemented in BISON are outlined. Code verification based on a recent IAEA benchmarking exercise is described, and excellant comparisons are reported. Multiple TRISO-coated particles of increasing geometric complexity are considered. It is shown that the code's ability to perform large-scale parallel computations permits application to complex 3D phenomena while very efficient solutions for either 1D spherically symmetric or 2D axisymmetric geometries are straightforward. Additionally, the flexibility to easily include new physical and material models and uncomplicated ability to couple to lower length scale simulations makes BISON a powerful tool for simulation of coated-particle fuel. Future code development activities and potential applications are identified.

  11. The neutronic and fuel cycle performance of interchangeable 3500 MWth metal and oxide fueled LMRs

    SciTech Connect

    Fujita, E.K.; Wade, D.C.

    1989-03-01

    This study summarizes the neutronic and fuel cycle analysis performed at Argonne National Laboratory for an oxide and a metal fueled 3500 MWth LMR. The oxide and metal core designs were developed to meet reactor performance specifications that are constrained by requirements for core loading interchangeability and for small burnup reactivity swing. Differences in the computed performance parameters of the oxide and metal cores, arising from basic differences in their neutronic characteristics, were identified and discussed. It is shown that metal and oxide cores designed to the same ground rules exhibit many similar performance characteristics; however, they differ substantially in reactivity coefficients, control strategies, and fuel cycle options. 12 refs., 25 figs.

  12. Feasibility study on AFR-100 fuel conversion from uranium-based fuel to thorium-based fuel

    SciTech Connect

    Heidet, F.; Kim, T.; Grandy, C.

    2012-07-30

    best core performance characteristics for each of them. With the exception of the fuel type and enrichment, the reference AFR-100 core design characteristics were kept unchanged, including the general core layout and dimensions, assembly dimensions, materials and power rating. In addition, the mass of {sup 235}U required was kept within a reasonable range from that of the reference AFR-100 design. The core performance characteristics, kinetics parameters and reactivity feedback coefficients were calculated using the ANL suite of fast reactor analysis code systems. Orifice design calculations and the steady-state thermal-hydraulic analyses were performed using the SE2-ANL code. The thermal margins were evaluated by comparing the peak temperatures to the design limits for parameters such as the fuel melting temperature and the fuel-cladding eutectic temperature. The inherent safety features of AFR-100 cores proposed were assessed using the integral reactivity parameters of the quasi-static reactivity balance analysis. The design objectives and requirements, the computation methods used as well as a description of the core concept are provided in Section 2. The three major approaches considered are introduced in Section 3 and the neutronics performances of those approaches are discussed in the same section. The orifice zoning strategies used and the steady-state thermal-hydraulic performance are provided in Section 4. The kinetics and reactivity coefficients, including the inherent safety characteristics, are provided in Section 5, and the Conclusions in Section 6. Other scenarios studied and sensitivity studies are provided in the Appendix section.

  13. Fuels planning: science synthesis and integration; forest structure and fire hazard fact sheet 03: visualizing forest structure and fuels

    Treesearch

    Rocky Mountain Research Station USDA Forest Service

    2004-01-01

    The software described in this fact sheet provides managers with tools for visualizing forest and fuels information. Computer-based landscape simulations can help visualize stand and landscape conditions and the effects of different management treatments and fuel changes over time. These visualizations can assist forest planning by considering a range of management...

  14. Neutronic fuel element fabrication

    DOEpatents

    Korton, George

    2004-02-24

    This disclosure describes a method for metallurgically bonding a complete leak-tight enclosure to a matrix-type fuel element penetrated longitudinally by a multiplicity of coolant channels. Coolant tubes containing solid filler pins are disposed in the coolant channels. A leak-tight metal enclosure is then formed about the entire assembly of fuel matrix, coolant tubes and pins. The completely enclosed and sealed assembly is exposed to a high temperature and pressure gas environment to effect a metallurgical bond between all contacting surfaces therein. The ends of the assembly are then machined away to expose the pin ends which are chemically leached from the coolant tubes to leave the coolant tubes with internal coolant passageways. The invention described herein was made in the course of, or under, a contract with the U.S. Atomic Energy Commission. It relates generally to fuel elements for neutronic reactors and more particularly to a method for providing a leak-tight metal enclosure for a high-performance matrix-type fuel element penetrated longitudinally by a multiplicity of coolant tubes. The planned utilization of nuclear energy in high-performance, compact-propulsion and mobile power-generation systems has necessitated the development of fuel elements capable of operating at high power densities. High power densities in turn require fuel elements having high thermal conductivities and good fuel retention capabilities at high temperatures. A metal clad fuel element containing a ceramic phase of fuel intimately mixed with and bonded to a continuous refractory metal matrix has been found to satisfy the above requirements. Metal coolant tubes penetrate the matrix to afford internal cooling to the fuel element while providing positive fuel retention and containment of fission products generated within the fuel matrix. Metal header plates are bonded to the coolant tubes at each end of the fuel element and a metal cladding or can completes the fuel-matrix enclosure

  15. Alternative aviation turbine fuels

    NASA Technical Reports Server (NTRS)

    Grobman, J.

    1977-01-01

    The efficient utilization of fossil fuels by future jet aircraft may necessitate the broadening of current aviation turbine fuel specifications. The most significant changes in specifications would be an increased aromatics content and a higher final boiling point in order to minimize refinery energy consumption and costs. These changes would increase the freezing point and might lower the thermal stability of the fuel and could cause increased pollutant emissions, increased smoke and carbon formation, increased combustor liner temperatures, and poorer ignition characteristics. This paper discusses the effects that broadened specification fuels may have on present-day jet aircraft and engine components and the technology required to use fuels with broadened specifications.

  16. Alternative aircraft fuels

    NASA Technical Reports Server (NTRS)

    Longwell, J. P.; Grobman, J. S.

    1977-01-01

    The efficient utilization of fossil fuels by future jet aircraft may necessitate the broadening of current aviation turbine fuel specifications. The most significant changes in specifications would be an increased aromatics content and a higher final boiling point in order to minimize refinery energy consumption and costs. These changes would increase the freezing point and might lower the thermal stability of the fuel, and could cause increased pollutant emissions, increased combustor liner temperatures, and poorer ignition characteristics. The effects that broadened specification fuels may have on present-day jet aircraft and engine components and the technology required to use fuels with broadened specifications are discussed.

  17. Fuel Cell Handbook update

    SciTech Connect

    Owens, W.R.; Hirschenhofer, J.H.; Engleman, R.R. Jr.; Stauffer, D.B.

    1993-11-01

    The objective of this work was to update the 1988 version of DOE`s Fuel Cell Handbook. Significant developments in the various fuel cell technologies required revisions to reflect state-of-the-art configurations and performance. The theoretical presentation was refined in order to make the handbook more useful to both the casual reader and fuel cell or systems analyst. In order to further emphasize the practical application of fuel cell technologies, the system integration information was expanded. In addition, practical elements, such as suggestions and guidelines to approximate fuel cell performance, were provided.

  18. Alternative aviation turbine fuels

    NASA Technical Reports Server (NTRS)

    Grobman, J.

    1977-01-01

    The efficient utilization of fossil fuels by future jet aircraft may necessitate the broadening of current aviation turbine fuel specifications. The most significant changes in specifications would be an increased aromatics content and a higher final boiling point in order to minimize refinery energy consumption and costs. These changes would increase the freezing point and might lower the thermal stability of the fuel and could cause increased pollutant emissions, increased smoke and carbon formation, increased combustor liner temperatures, and poorer ignition characteristics. This paper discusses the effects that broadened specification fuels may have on present-day jet aircraft and engine components and the technology required to use fuels with broadened specifications.

  19. Fuel characteristics pertinent to the design of aircraft fuel systems

    NASA Technical Reports Server (NTRS)

    Barnett, Henry C; Hibbard, R R

    1953-01-01

    Because of the importance of fuel properties in design of aircraft fuel systems the present report has been prepared to provide information on the characteristics of current jet fuels. In addition to information on fuel properties, discussions are presented on fuel specifications, the variations among fuels supplied under a given specification, fuel composition, and the pertinence of fuel composition and physical properties to fuel system design. In some instances the influence of variables such as pressure and temperature on physical properties is indicated. References are cited to provide fuel system designers with sources of information containing more detail than is practicable in the present report.

  20. Fossil fuels supplies modeling and research

    SciTech Connect

    Leiby, P.N.

    1996-06-01

    The fossil fuel supplies modeling and research effort focuses on models for US Strategic Petroleum Reserve (SPR) planning and management. Topics covered included new SPR oil valuation models, updating models for SPR risk analysis, and fill-draw planning. Another task in this program area is the development of advanced computational tools for three-dimensional seismic analysis.

  1. NUCLEAR REACTOR FUEL ELEMENT

    DOEpatents

    Wheelock, C.W.; Baumeister, E.B.

    1961-09-01

    A reactor fuel element utilizing fissionable fuel materials in plate form is described. This fuel element consists of bundles of fuel-bearing plates. The bundles are stacked inside of a tube which forms the shell of the fuel element. The plates each have longitudinal fins running parallel to the direction of coolant flow, and interspersed among and parallel to the fins are ribs which position the plates relative to each other and to the fuel element shell. The plate bundles are held together by thin bands or wires. The ex tended surface increases the heat transfer capabilities of a fuel element by a factor of 3 or more over those of a simple flat plate.

  2. Fuel nozzle assembly

    DOEpatents

    Johnson, Thomas Edward; Ziminsky, Willy Steve; Lacey, Benjamin Paul; York, William David; Stevenson, Christian Xavier

    2011-08-30

    A fuel nozzle assembly is provided. The assembly includes an outer nozzle body having a first end and a second end and at least one inner nozzle tube having a first end and a second end. One of the nozzle body or nozzle tube includes a fuel plenum and a fuel passage extending therefrom, while the other of the nozzle body or nozzle tube includes a fuel injection hole slidably aligned with the fuel passage to form a fuel flow path therebetween at an interface between the body and the tube. The nozzle body and the nozzle tube are fixed against relative movement at the first ends of the nozzle body and nozzle tube, enabling the fuel flow path to close at the interface due to thermal growth after a flame enters the nozzle tube.

  3. Fuel injection apparatus

    SciTech Connect

    Omori, T.; Sakakibara, S.; Kato, M.; Masuda, A.

    1986-06-10

    A fuel injection apparatus is described for supplying fuel from a fuel tank to at least one combustion chamber of an internal combustion engine, comprising: an injector housing defining therein a pressure cylinder bore, an injection cylinder bore and a timing cylinder bore connected in series with the pressure cylinder bore; a pressure plunger, fitted in the pressure cylinder bore and having one end defining, in the pressure cylinder bore, a pressure pump chamber communicating with the injection cylinder bore and the timing cylinder bore; first fuel supply means for supplying fuel from the fuel tank to the pressure pump chamber; pressurizing means for reciprocating the pressure plunger in the pressure cylinder bore in synchronism with the engine operation so as to pressurize fuel in the pressure pump chamber; an injection plunger, having a diameter smaller than the pressure plunger, fitted in the injection cylinder bore and having two ends defining, in the injection cylinder bore, an injection pump chamber and a first communicating chamber communicating with the pressure pump chamber; second fuel supply means for adjusting the quantity of the fuel from the fuel tank in accordance with engine operation conditions so as to supply the adjusted fuel quantity to the injection pump chamber; injection valve means for injecting the fuel into the fuel pump chamber toward a combustion chamber of the engine when the pressure in the pressure pump chamber is applied to the injection plunger through the first communicating chamber, and the fuel pressure in the injection pump chamber reaches a predetermined injection pressure.

  4. Gaseous Fuel Injection Modeling using a Gaseous Sphere Injection Methodology

    SciTech Connect

    Hessel, R P; Aceves, S M; Flowers, D L

    2006-03-06

    The growing interest in gaseous fuels (hydrogen and natural gas) for internal combustion engines calls for the development of computer models for simulation of gaseous fuel injection, air entrainment and the ensuing combustion. This paper introduces a new method for modeling the injection and air entrainment processes for gaseous fuels. The model uses a gaseous sphere injection methodology, similar to liquid droplet in injection techniques used for liquid fuel injection. In this paper, the model concept is introduced and model results are compared with correctly- and under-expanded experimental data.

  5. A method for monitoring nuclear absorption coefficients of aviation fuels

    NASA Technical Reports Server (NTRS)

    Sprinkle, Danny R.; Shen, Chih-Ping

    1989-01-01

    A technique for monitoring variability in the nuclear absorption characteristics of aviation fuels has been developed. It is based on a highly collimated low energy gamma radiation source and a sodium iodide counter. The source and the counter assembly are separated by a geometrically well-defined test fuel cell. A computer program for determining the mass attenuation coefficient of the test fuel sample, based on the data acquired for a preset counting period, has been developed and tested on several types of aviation fuel.

  6. Metallic fuels: The EBR-II legacy and recent advances

    SciTech Connect

    Douglas L. Porter; Steven L. Hayes; J. Rory Kennedy

    2012-09-01

    Experimental Breeder Reactor – II (EBR-II) metallic fuel was qualified for high burnup to approximately 10 atomic per cent. Subsequently, the electrometallurgical treatment of this fuel was demonstrated. Advanced metallic fuels are now investigated for increased performance, including ultra-high burnup and actinide burning. Advances include additives to mitigate the fuel/cladding chemical interaction and uranium alloys that combine Mo, Ti and Zr to improve alloy performance. The impacts of the advances—on fabrication, waste streams, electrorefining, etc.—are found to be minimal and beneficial. Owing to extensive research literature and computational methods, only a modest effort is required to complete their development.

  7. Alternative fuels for mobile fuel cells

    NASA Astrophysics Data System (ADS)

    Calabrese Barton, Scott Andrew

    1999-11-01

    Because of limitations associated with the use of hydrogen fuel, the direct use of alternative fuels in fuel cells has been the focus of intense research. Two fuels worthy of consideration are methanol and zinc. This work considers aspects of implementing these fuels in mobile fuel cell applications. Two chapters treat topics relating to direct methanol fuel cells, and three chapters consider the cathode and anode of the zinc-air cell. A methanol concentration sensor is crucial to the control of a direct methanol fuel cell system. The design considered here is based on current output limited by methanol diffusion through a proton exchange membrane. The sensor provides first-order response to changes in concentration and temperature over a concentration range of 0 to 3 M, with a response on the order of 10 seconds. A mixed-reactant, strip-cell direct methanol fuel cell concept is discussed. In this type of cell, reaction-selective electrodes are mounted in an alternating fashion on the same side of a membrane electrolyte, allowing mixing of feed streams, and reduced system complexity. The performance of prototypical cells is demonstrated, and improved fuel efficiency at low current density is predicted. Geometric constraints on the performance of such cells are also considered. A primary zinc-air cell may be considered a fuel cell if the anode is replaceable. The cathode of such a cell is analyzed using a numerical model. Results indicate that oxygen solubility and diffusion in the electrolyte dominate polarization losses. Reduced catalyst particle size and decreased electrolyte concentration are suggested to improve cathode performance. Whereas the air cathode may be modeled adequately, given the wealth of information available on oxygen kinetics, the oxidation of zinc is not well-understood. Thus, the mass-transfer-limited region of zinc electrodissolution was investigated using a zinc rotating disk electrode and electrochemical impedance techniques. The zincate

  8. FAST: A Fuel And Sheath Modeling Tool for CANDU Reactor Fuel

    NASA Astrophysics Data System (ADS)

    Prudil, Andrew Albert

    Understanding the behaviour of nuclear fuel during irradiation is a complicated multiphysics problem involving neutronics, chemistry, radiation physics, material-science, solid mechanics, heat transfer and thermal-hydraulics. Due to the complexity and interdependence of the physics and models involved, fuel modeling is typically clone with numerical models. Advancements in both computer hardware and software have made possible new more complex and sophisticated fuel modeling codes. The Fuel And Sheath modelling Tool (FAST) is a fuel performance code that has been developed for modeling nuclear fuel behaviour under normal and transient conditions. The FAST code includes models for heat generation and transport, thermal expansion, elastic strain, densification, fission product swelling, pellet relocation, contact, grain growth, fission gas release, gas and coolant pressure and sheath creep. These models are coupled and solved numerically using the Comsol Multiphysics finite-element platform. The model utilizes a radialaxial geometry of a fuel pellet (including dishing and chamfering) and accompanying fuel sheath allowing the model to predict circumferential ridging. This model has evolved from previous treatments developed at the Royal Military College. The model has now been significantly advanced to include: a more detailed pellet geometry, localized pellet-to-sheath gap size and contact pressure, ability to model cracked pellets, localized fuel burnup for material property models, improved U02 densification behaviour, fully 2-dimensional model for the sheath, additional creep models, additional material models, an FEM Booth-diffusion model for fission gas release (including ability to model temperature and power changes), a capability for end-of-life predictions, the ability to utilize text files as model inputs, and provides a first time integration of normal operating conditions (NOC) and transient fuel models into a single code (which has never been achieved

  9. Fuel cell market applications

    SciTech Connect

    Williams, M.C.

    1995-12-31

    This is a review of the US (and international) fuel cell development for the stationary power generation market. Besides DOE, GRI, and EPRI sponsorship, the US fuel cell program has over 40% cost-sharing from the private sector. Support is provided by user groups with over 75 utility and other end-user members. Objectives are to develop and demonstrate cost-effective fuel cell power generation which can initially be commercialized into various market applications using natural gas fuel by the year 2000. Types of fuel cells being developed include PAFC (phosphoric acid), MCFC (molten carbonate), and SOFC (solid oxide); status of each is reported. Potential international applications are reviewed also. Fuel cells are viewed as a force in dispersed power generation, distributed power, cogeneration, and deregulated industry. Specific fuel cell attributes are discussed: Fuel cells promise to be one of the most reliable power sources; they are now being used in critical uninterruptible power systems. They need hydrogen which can be generated internally from natural gas, coal gas, methanol landfill gas, or other fuels containing hydrocarbons. Finally, fuel cell development and market applications in Japan are reviewed briefly.

  10. Diesel fuel injection system

    SciTech Connect

    Schechter, M.M.; Simko, A.O.

    1986-04-22

    A fuel injection pump is described of the multiple plunger spill port type for an automotive type internal combustion engine, the pump including at least four axially spaced engine camshaft driven pump plungers grouped in pairs and sequentially and in succession moved in one direction through a fuel pumping stroke and oppositely through a fuel intake stroke. A fuel pressurization/supply chamber is contiquous to the end of each plunger for pressurization of the fuel therein or supply of fuel thereto from a supply passage upon coordinate movement of the plunger, fill/spill passage means connected to a single fuel return spill port and in parallel flow relationship to each of the plunger bores as a function of the position of the plungers, each plunger having a pair of internal passages connected at all times to its chamber and alternately alignable with the supply or fill/spill passage means as a function of the position of the plunger. A fuel discharge passage is operatively connecting each of the chambers to an individual engine cylinder, a single spill port control valve movable to block or permit the spill of fuel through the spill port to a return line to control the pressurization of fuel in all of the fuel chambers and associated discharge passages, a single solenoid connected to the spill control valve for moving it to block or unblock the spill port, and a single shuttle valve operatively associated with all of the fill/spill passage means and spill port reciprocably movable between positions to sequentially connect the plunger chambers one at a time in succession to the spill port during the pumping pressurization stroke of its plunger for the injection of fuel to an individual cylinder while the other chambers are in various stages of being refilled with fuel and preparing for pressurization upon successive actuation of the plungers by the camshaft.

  11. Kinetic Modeling of Combustion Characteristics of Real Biodiesel Fuels

    SciTech Connect

    Naik, C V; Westbrook, C K

    2009-04-08

    Biodiesel fuels are of much interest today either for replacing or blending with conventional fuels for automotive applications. Predicting engine effects of using biodiesel fuel requires accurate understanding of the combustion characteristics of the fuel, which can be acquired through analysis using reliable detailed reaction mechanisms. Unlike gasoline or diesel that consists of hundreds of chemical compounds, biodiesel fuels contain only a limited number of compounds. Over 90% of the biodiesel fraction is composed of 5 unique long-chain C{sub 18} and C{sub 16} saturated and unsaturated methyl esters. This makes modeling of real biodiesel fuel possible without the need for a fuel surrogate. To this end, a detailed chemical kinetic mechanism has been developed for determining the combustion characteristics of a pure biodiesel (B100) fuel, applicable from low- to high-temperature oxidation regimes. This model has been built based on reaction rate rules established in previous studies at Lawrence Livermore National Laboratory. Computed results are compared with the few fundamental experimental data that exist for biodiesel fuel and its components. In addition, computed results have been compared with experimental data for other long-chain hydrocarbons that are similar in structure to the biodiesel components.

  12. Alternative fuels for road vehicles

    SciTech Connect

    Poulton, M.L.

    1994-12-31

    The finite nature of global fossil fuel resources underscores the need to develop alternative vehicular fuels. Increased use of renewable and alternative fuels can extend fossil fuel supplies and help resolve air pollution problems inherent in automotive use of conventional fuels. Fuel characteristics, safety implications, feedstocks, infrastructure, fuel production costs, emissions performance, required vehicle modifications, and outlook are described for LPG, reformulated gasoline, natural gas, hydrogen, electricity, biofuels, ethanol, and methanol. 26 fig., 288 refs., 29 tabs.

  13. Coupling hydrogen fuel and carbonless utilities

    SciTech Connect

    Berry, G.D.

    1998-08-01

    A number of previous analyses have focused on comparisons of single hydrogen vehicles to petroleum and alternative fuel vehicles or of stationary hydrogen storage for utility or local power applications. LLNL`s approach is to compare combined transportation/utility storage systems using hydrogen and fossil fuels. Computer models have been constructed to test the hypothesis that combining carbonless electricity sources and vehicles fueled by electrolytic hydrogen can reduce carbon emissions more cost effectively than either approach alone. Three scenarios have been developed and compared using computer simulations, hourly utility demand data, representative data for solar and wind energy sites, and the latest available EIA projections for transportation and energy demand in the US in 2020. Cost projections were based on estimates from GRI, EIA, and a recent DOE/EPRI report on renewable energy technologies. The key question guiding this analysis was: what can be gained by combining hydrogen fuel production and renewable electricity? Bounding scenarios were chosen to analyze three carbon conscious options for the US transportation fuel and electricity supply system beyond 2020: Reference Case -- petroleum transportation and natural gas electric sector; Benchmark Case -- petroleum transportation and carbonless electric sector; and Target Case -- hydrogen transportation and carbonless electric sector.

  14. Advanced fuel system technology for utilizing broadened property aircraft fuels

    NASA Technical Reports Server (NTRS)

    Reck, G. M.

    1980-01-01

    Factors which will determine the future supply and cost of aviation turbine fuels are discussed. The most significant fuel properties of volatility, fluidity, composition, and thermal stability are discussed along with the boiling ranges of gasoline, naphtha jet fuels, kerosene, and diesel oil. Tests were made to simulate the low temperature of an aircraft fuel tank to determine fuel tank temperatures for a 9100-km flight with and without fuel heating; the effect of N content in oil-shale derived fuels on the Jet Fuel Thermal Oxidation Tester breakpoint temperature was measured. Finally, compatibility of non-metallic gaskets, sealants, and coatings with increased aromatic content jet fuels was examined.

  15. Metallic Fuel Casting Development and Parameter Optimization Simulations

    SciTech Connect

    R.S. Fielding; J. Crapps; C. Unal; J.R. Kennedy

    2013-03-01

    One of the advantages of metallic fuel is the abilility to cast the fuel slugs to near net shape with little additional processing. However, the high aspect ratio of the fuel is not ideal for casting. EBR-II fuel was cast using counter gravity injection casting (CGIC) but, concerns have been raised concerning the feasibility of this process for americium bearing alloys. The Fuel Cycle Research and Development program has begun developing gravity casting techniques suitable for fuel production. Compared to CGIC gravity casting does not require a large heel that then is recycled, does not require application of a vacuum during melting, and is conducive to re-usable molds. Development has included fabrication of two separate benchscale, approximately 300 grams, systems. To shorten development time computer simulations have been used to ensure mold and crucible designs are feasible and to identify which fluid properties most affect casting behavior and therefore require more characterization.

  16. BISON Theory Manual The Equations behind Nuclear Fuel Analysis

    SciTech Connect

    Hales, J. D.; Williamson, R. L.; Novascone, S. R.; Pastore, G.; Spencer, B. W.; Stafford, D. S.; Gamble, K. A.; Perez, D. M.; Liu, W.

    2016-09-01

    BISON is a finite element-based nuclear fuel performance code applicable to a variety of fuel forms including light water reactor fuel rods, TRISO particle fuel, and metallic rod and plate fuel. It solves the fully-coupled equations of thermomechanics and species diffusion, for either 2D axisymmetric or 3D geometries. Fuel models are included to describe temperature and burnup dependent thermal properties, fission product swelling, densification, thermal and irradiation creep, fracture, and fission gas production and release. Plasticity, irradiation growth, and thermal and irradiation creep models are implemented for clad materials. Models are also available to simulate gap heat transfer, mechanical contact, and the evolution of the gap/plenum pressure with plenum volume, gas temperature, and fission gas addition. BISON is based on the MOOSE framework and can therefore efficiently solve problems using standard workstations or very large high-performance computers. This document describes the theoretical and numerical foundations of BISON.

  17. Heat-Exchanger Computational Procedure For Temperature-Dependent Fouling

    NASA Technical Reports Server (NTRS)

    Chiappetta, L.; Szetela, E.

    1985-01-01

    Computer program predicts heat-exchanger performance under variety of conditions. Program provides rapid means of calculating distribution of fluid and wall temperatures, fuel deposit formation, and pressure losses at various locations in heat exchanger. Developed for use with heat exchanger that vaporizes fuel prior to fuel ignition; other applications possible.

  18. Fuel cell generator with fuel electrodes that control on-cell fuel reformation

    DOEpatents

    Ruka, Roswell J.; Basel, Richard A.; Zhang, Gong

    2011-10-25

    A fuel cell for a fuel cell generator including a housing including a gas flow path for receiving a fuel from a fuel source and directing the fuel across the fuel cell. The fuel cell includes an elongate member including opposing first and second ends and defining an interior cathode portion and an exterior anode portion. The interior cathode portion includes an electrode in contact with an oxidant flow path. The exterior anode portion includes an electrode in contact with the fuel in the gas flow path. The anode portion includes a catalyst material for effecting fuel reformation along the fuel cell between the opposing ends. A fuel reformation control layer is applied over the catalyst material for reducing a rate of fuel reformation on the fuel cell. The control layer effects a variable reformation rate along the length of the fuel cell.

  19. Future Transient Testing of Advanced Fuels

    SciTech Connect

    Jon Carmack

    2009-09-01

    The transient in-reactor fuels testing workshop was held on May 4–5, 2009 at Idaho National Laboratory. The purpose of this meeting was to provide a forum where technical experts in transient testing of nuclear fuels could meet directly with technical instrumentation experts and nuclear fuel modeling and simulation experts to discuss needed advancements in transient testing to support a basic understanding of nuclear fuel behavior under off-normal conditions. The workshop was attended by representatives from Commissariat à l'Énergie Atomique CEA, Japanese Atomic Energy Agency (JAEA), Department of Energy (DOE), AREVA, General Electric – Global Nuclear Fuels (GE-GNF), Westinghouse, Electric Power Research Institute (EPRI), universities, and several DOE national laboratories. Transient testing of fuels and materials generates information required for advanced fuels in future nuclear power plants. Future nuclear power plants will rely heavily on advanced computer modeling and simulation that describes fuel behavior under off-normal conditions. TREAT is an ideal facility for this testing because of its flexibility, proven operation and material condition. The opportunity exists to develop advanced instrumentation and data collection that can support modeling and simulation needs much better than was possible in the past. In order to take advantage of these opportunities, test programs must be carefully designed to yield basic information to support modeling before conducting integral performance tests. An early start of TREAT and operation at low power would provide significant dividends in training, development of instrumentation, and checkout of reactor systems. Early start of TREAT (2015) is needed to support the requirements of potential users of TREAT and include the testing of full length fuel irradiated in the FFTF reactor. The capabilities provided by TREAT are needed for the development of nuclear power and the following benefits will be realized by the

  20. Alcohol fuels for aviation

    SciTech Connect

    Schauffler, P.

    1982-06-01

    The ten-fold increase in aviation fuel prices in eight years has caused a reassessment of alcohol fuels. In a recent test, methanol fuel-flow rate was high at takeoff, and levelled off at 10,000 feet, but above 18,000 fell 30% below avgas use. Because methanol sells thirty cents below avgas per gallon it is already an attractive fuel for piston-engine aircraft. But as 95% of aviation fuel is burned as kerosene in turbines a test program has been set up to look at the performance of small shaft turbine engines with various combinations of alcohols and water, and of straight methanol, and to look at major thrust engine at optimum fuel as well. These tests should determine the overall alcohol potentials for aviation. The tests will also tell if the breakthrough will be modest or major.

  1. REACTOR FUEL SCAVENGING MEANS

    DOEpatents

    Coffinberry, A.S.

    1962-04-10

    A process for removing fission products from reactor liquid fuel without interfering with the reactor's normal operation or causing a significant change in its fuel composition is described. The process consists of mixing a liquid scavenger alloy composed of about 44 at.% plutoniunm, 33 at.% lanthanum, and 23 at.% nickel or cobalt with a plutonium alloy reactor fuel containing about 3 at.% lanthanum; removing a portion of the fuel and scavenger alloy from the reactor core and replacing it with an equal amount of the fresh scavenger alloy; transferring the portion to a quiescent zone where the scavenger and the plutonium fuel form two distinct liquid layers with the fission products being dissolved in the lanthanum-rich scavenger layer; and the clean plutonium-rich fuel layer being returned to the reactor core. (AEC)

  2. Spiral cooled fuel nozzle

    DOEpatents

    Fox, Timothy; Schilp, Reinhard

    2012-09-25

    A fuel nozzle for delivery of fuel to a gas turbine engine. The fuel nozzle includes an outer nozzle wall and a center body located centrally within the nozzle wall. A gap is defined between an inner wall surface of the nozzle wall and an outer body surface of the center body for providing fuel flow in a longitudinal direction from an inlet end to an outlet end of the fuel nozzle. A turbulating feature is defined on at least one of the central body and the inner wall for causing at least a portion of the fuel flow in the gap to flow transverse to the longitudinal direction. The gap is effective to provide a substantially uniform temperature distribution along the nozzle wall in the circumferential direction.

  3. An Innovative High Thermal Conductivity Fuel Design

    SciTech Connect

    Jamil A. Khan

    2009-11-21

    Thermal conductivity of the fuel in today's Light Water Reactors, Uranium dioxide, can be improved by incorporating a uniformly distributed heat conducting network of a higher conductivity material, Silicon Carbide. The higher thermal conductivity of SiC along with its other prominent reactor-grade properties makes it a potential material to address some of the related issues when used in UO2 [97% TD]. This ongoing research, in collaboration with the University of Florida, aims to investigate the feasibility and develop a formal methodology of producing the resultant composite oxide fuel. Calculations of effective thermal conductivity of the new fuel as a function of %SiC for certain percentages and as a function of temperature are presented as a preliminary approach. The effective thermal conductivities are obtained at different temperatures from 600K to 1600K. The corresponding polynomial equations for the temperature-dependent thermal conductivities are given based on the simulation results. Heat transfer mechanism in this fuel is explained using a finite volume approach and validated against existing empirical models. FLUENT 6.1.22 was used for thermal conductivity calculations and to estimate reduction in centerline temperatures achievable within such a fuel rod. Later, computer codes COMBINE-PC and VENTURE-PC were deployed to estimate the fuel enrichment required, to maintain the same burnup levels, corresponding to a volume percent addition of SiC.

  4. MOLTEN CARBONATE FUEL CELL PRODUCT DESIGN IMPROVEMENT

    SciTech Connect

    H.C. Maru; M. Farooque

    2003-03-01

    The program efforts are focused on technology and system optimization for cost reduction, commercial design development, and prototype system field trials. The program is designed to advance the carbonate fuel cell technology from full-size field test to the commercial design. FuelCell Energy, Inc. (FCE) is in the later stage of the multiyear program for development and verification of carbonate fuel cell based power plants supported by DOE/NETL with additional funding from DOD/DARPA and the FuelCell Energy team. FCE has scaled up the technology to full-size and developed DFC{reg_sign} stack and balance-of-plant (BOP) equipment technology to meet product requirements, and acquired high rate manufacturing capabilities to reduce cost. FCE has designed submegawatt (DFC300A) and megawatt (DFC1500 and DFC3000) class fuel cell products for commercialization of its DFC{reg_sign} technology. A significant progress was made during the reporting period. The reforming unit design was optimized using a three-dimensional stack simulation model. Thermal and flow uniformities of the oxidant-In flow in the stack module were improved using computational fluid dynamics based flow simulation model. The manufacturing capacity was increased. The submegawatt stack module overall cost was reduced by {approx}30% on a per kW basis. An integrated deoxidizer-prereformer design was tested successfully at submegawatt scale using fuels simulating digester gas, coal bed methane gas and peak shave (natural) gas.

  5. Innovative nuclear fuels: results and strategy

    SciTech Connect

    Stan, Marius

    2009-01-01

    To facilitate the discovery and design of innovative nuclear fuels, multi-scale models and simulations are used to predict irradiation effects on the thermal conductivity, oxygen diffusivity, and thermal expansion of oxide fuels. The multi-scale approach is illustrated using results on ceramic fuels with a focus on predictions of point defect concentrations, stoichiometry, and phase stability. The high performance computer simulations include coupled heat transport, diffusion, and thermal expansion, gas bubble formation and temperature evolution in a fuel element consisting of UO2 fuel and metallic cladding. The second part of the talk is dedicated to a discussion of an international strategy for developing advanced, innovative nuclear fuels. Four initiative are proposed to accelerate the discovery and design of new materials: (a) Develop an international pool of experts, (b) Create Institutes for Materials Discovery and Design, (c) Create an International Knowledge base for experimental data, models (mathematical expressions), and simulations (codes) and (d) Organize international workshops and conference sessions. The paper ends with a discussion of existing and emerging international collaborations.

  6. Fuel injection system for internal combustion engines

    SciTech Connect

    Yamaguchi, S.

    1986-10-28

    A fuel injection system is described for an internal combustion engine, comprising: (a) a fuel injection pump driven by the engine for fuel injection thereto and including a plunger reciprocably movable at a non-uniform speed and a control sleeve slidably fitted on the plunger; (b) first drive means operatively connected with the plunger for rotating the latter to thereby adjust the effective stroke of the plunger; (c) second drive means operatively connected with the control sleeve for displacing the latter in an axial direction to thereby adjust the pre-stroke of the control sleeve; (d) an operation sensor for detecting operating conditions of the engine; (e) a position sensor for detecting a position of the control sleeve; (f) first arithmetic means responsive to the engine operating conditions detected by the operation sensor, for computing an object injection quantity; (g) second arithmetic means responsive to the position of the control sleeve detected by the position sensor, for computing an object pre-stroke of the plunger; (h) third arithmetic means responsive to the engine operating conditions detected and the position of the control sleeve detected, for computing a correction amount; (i) first control means responsive to the correction amount computed by the third arithmetic means, for correcting the object injection quantity and for delivering a control signal to the first drive means; and (j) second control means responsive to the object injection quantity computed by the second arithmetic means, for delivering a control signal to the second drive means.

  7. High energy fuel compositions

    SciTech Connect

    Fisher, D.H.

    1983-07-19

    A high density liquid hydrocarbon fuel composition is disclosed, singularly suited for propelling turbojet limited volume missile systems designed for shipborne deployment. The contemplated fuels are basically composed of the saturated analogues of dimers of methyl cyclopentadiene and of dicyclopentadiene and optionally include the saturated analogues of the co-trimers of said dienes or the trimers of cyclopentadiene. The various dimers and trimers are combined in a relative relationship to provide optimal performing fuels for the indicated purpose.

  8. Food for fuel

    SciTech Connect

    Bell, J.

    1982-05-01

    Cassava, sugar cane, grain crops, molasses - all are potential feedstocks for ethanol production. Brazil has taken a clear lead in converting food crops into ethanol fuels for the automobile, but other countries may follow and the economic consequences could be considerable. This article looks at the various options. The total activity involved in fuel ethanol production and usage is considered as comprising three related components: feedstock production, ethanol production and application of the ethanol as a transport fuel.

  9. Alternative Fuels Infrastructure Development

    SciTech Connect

    Bloyd, Cary N.

    2010-06-30

    This summary reviews the status of alternate transportation fuels development and utilization in Thailand. An understanding of the issues and experiences associated with the introduction of alternative fuels in other countries can help the US in anticipation potential problems as it introduces new automotive fuels. Thailand is of particular interest since it introduced E20 to its commercial market in 2007 and the US is now considering introducing E20 into the US market.

  10. Liquid fuel cells.

    PubMed

    Soloveichik, Grigorii L

    2014-01-01

    The advantages of liquid fuel cells (LFCs) over conventional hydrogen-oxygen fuel cells include a higher theoretical energy density and efficiency, a more convenient handling of the streams, and enhanced safety. This review focuses on the use of different types of organic fuels as an anode material for LFCs. An overview of the current state of the art and recent trends in the development of LFC and the challenges of their practical implementation are presented.

  11. Liquid fuel cells

    PubMed Central

    2014-01-01

    Summary The advantages of liquid fuel cells (LFCs) over conventional hydrogen–oxygen fuel cells include a higher theoretical energy density and efficiency, a more convenient handling of the streams, and enhanced safety. This review focuses on the use of different types of organic fuels as an anode material for LFCs. An overview of the current state of the art and recent trends in the development of LFC and the challenges of their practical implementation are presented. PMID:25247123

  12. Fuels Combustion Research.

    DTIC Science & Technology

    1984-07-18

    uncertainties in the future sources and characteristics of fuels has emphasized the need to better understand fuel effects on combustion , e.g. energy release...experimentally to be made. Unsuccessful comparisons can lead to impro- vements in modelling concepts . Two simplified models for the combustion of slurry...AD-A149 186 FUELS COMBUSTION RESEACCH(U) PRINCETON UNIV NJ DEPT OF i/i MECHANICAL AND AEROSPACE ENGINEERING F L DRYER ET AL. 18 JUL 84 NAE-i668 AFOSR

  13. Fuel Stability Foam

    DTIC Science & Technology

    1988-08-01

    rupture 1161. Foams containing either polyether or polyester polyols are fuel-compatible, but the polyether variety is considerably less susceptible to...General details of the foams are given in Table 2. Foams containing polyether and polyester polyols , either with reticulated on non- 3 - reticulated...mainly for fuel slosh attenuation, and explosion suppression properties [161. Foams containing either polyether or polyester polyols can be fuel

  14. Portable Fuel Quality Analyzer

    DTIC Science & Technology

    2014-01-27

    other transportation industries, such as trucking. The PFQA could also be used in fuel blending operations performed at petroleum, ethanol and biodiesel plants. ...used to identify fuel type and determine performance properties. The Phase I measurements identified the best spectral resolution, spectral region and...identified the best spectral resolution, spectral region and sample path length to differentiate between diesel and jet fuels, as well as to determine

  15. Influence of test fuel properties and composition on UNECE R101 CO2 and fuel economy valuation

    NASA Astrophysics Data System (ADS)

    Parker, A.

    2015-12-01

    CO2 emission and fuel consumption of passenger cars is now assessed by using a simplistic procedure measuring the emission during a test performed without any control of the fuel properties and computing the fuel consumption through an unsophisticated formula. As pump gasoline and diesel fuels are refinery products mixture of many different hydrocarbons, and in case of gasoline may also contain a significant amount of oxygenates, the fuel properties, including the density, carbon and energy content may strongly vary from one pump fuel to the other. Being the specific test fuels carefully selected by the car manufacturers and everything but randomly chosen pump fuels, the claimed CO2 emission and fuel economy figures may differ largely from the certification values. I show from the analysis of the 2014 UK government data for 2358 diesel and 2103 petrol vehicles how same volumes of only theoretically same pump fuels used during the certification test by the cars manufacturers unfortunately do not produce the same carbon dioxide emission, and very likely do not have the same energy content. The CO2 emission per liter of diesel fuel is shown to oscillate froma maximum of 3049 g to a minimum of 2125 g, with an average of 2625 g, froma +16.13% to a -19.06% of the average. TheCO2 emission per liter of petrol fuel is shown to oscillate even more from a maximum of 3735 g to a minimum of 1767 g with an average of 2327 g, from a +60.48% to a -24.05% of the average. The proposed solution is to center the assessment on the energy demand by measuring with accuracy the mass of fuel consumed and the fuel properties of the test fuel starting from the lower heating. The corrected fuel consumption and the corrected carbon dioxide emission to mention from the test are then computed by using pure hydrocarbon reference fuels for diesel and petrol having a given lower heating value and a given hydrocarbon composition. Alternatively, exactly the same test fuel should be used by all the

  16. Thermal-hydraulic/heat transfer code development for sphere-pac-fueled LMFBRs. [COBRA-3SP code

    SciTech Connect

    Morris, D.G.

    1980-06-01

    Sphere-pac fuel has received much attention recently in light of the development of proliferation-resistant fuel cycles for the Fast Breeder Reactor Program in the United States. However, for sphere-pac fuel to be a viable alternative to conventional pellet fuel, a means to analyze the thermal behavior of sphere-pac-fueled pin bundles is needed. To meet this need, a thermal-hydraulic/heat transfer computer code has been developed for sphere-pac-fueled fast breeder reactors. The code, COBRA-3SP, is a modified version of COBRA-3M incorporating a three-region sphere-pac fuel pin model which permits fuel restructuring. With COBRA-3SP, steady-state and transient analysis of sphere-pac-fueled pin bundles is possible. The validity of the sphere-pac fuel pin model has been verified using experimental results of irradiated sphere-pac fuel.

  17. Metallic fuel safety assessment

    SciTech Connect

    Bauer, T. H.; Cahalan, J. E.; Dunn, F. E.; Fenske, G. R.; Gabor, J. D.; Gruber, E. E.; Hughes, T. H.; Kalimullah, none; Kramer, J. M.; Miles, K. J.; Pedersen, D. R.; Spencer, B. W.; Tentner, A. M.; Tilbrook, R. W.; Wright, A. E.

    1989-02-01

    A survey of experimental and analytical results from the Integral Fast Reactor (IFR) safety program are presented, with a focus on metallic fuel safety performance. Experimental results from laboratory and in-pile tests are reviewed. Models of metallic fuel behavior for prediction of performance in reactor transients and accidents are summarized. Analyses of metallic fuel response in design basis accidents and anticipated transients without scram are presented. The experimental and analytical databases demonstrate the superior safety performance of metallic fuel in IFR design concepts.

  18. FUEL ASSAY REACTOR

    DOEpatents

    Spinrad, B.I.; Sandmeier, H.A.; Martens, F.H.

    1962-12-25

    A reactor having maximum sensitivity to perturbations is described comprising a core consisting of a horizontally disposed, rectangular, annular fuel zone containing enriched uranium dioxide dispersed in graphite, the concentration of uranium dioxide increasing from the outside to the inside of the fuel zone, an internal reflector of graphite containing an axial test opening disposed within the fuel zone, an external graphite reflector, means for changing the neutron spectrum in the test opening, and means for measuring perturbations in the neutron flux caused by the introduction of different fuel elements into the test opening. (AEC)

  19. NUCLEAR REACTOR FUEL SYSTEMS

    DOEpatents

    Thamer, B.J.; Bidwell, R.M.; Hammond, R.P.

    1959-09-15

    Homogeneous reactor fuel solutions are reported which provide automatic recombination of radiolytic gases and exhibit large thermal expansion characteristics, thereby providing stability at high temperatures and enabling reactor operation without the necessity of apparatus to recombine gases formed by the radiolytic dissociation of water in the fuel and without the necessity of liquid fuel handling outside the reactor vessel except for recovery processes. The fuels consist of phosphoric acid and water solutions of enriched uranium, wherein the uranium is in either the hexavalent or tetravalent state.

  20. Fuel cell arrangement

    DOEpatents

    Isenberg, Arnold O.

    1987-05-12

    A fuel cell arrangement is provided wherein cylindrical cells of the solid oxide electrolyte type are arranged in planar arrays where the cells within a plane are parallel. Planes of cells are stacked with cells of adjacent planes perpendicular to one another. Air is provided to the interior of the cells through feed tubes which pass through a preheat chamber. Fuel is provided to the fuel cells through a channel in the center of the cell stack; the fuel then passes the exterior of the cells and combines with the oxygen-depleted air in the preheat chamber.

  1. NEUTRONIC REACTOR FUEL ELEMENT

    DOEpatents

    Shackleford, M.H.

    1958-12-16

    A fuel element possessing good stability and heat conducting properties is described. The fuel element comprises an outer tube formed of material selected from the group consisting of stainhess steel, V, Ti. Mo. or Zr, a fuel tube concentrically fitting within the outer tube and containing an oxide of an isotope selected from the group consisting of U/sup 235/, U/sup 233/, and Pu/sup 239/, and a hollow, porous core concentrically fitting within the fuel tube and formed of an oxide of an element selected from the group consisting of Mg, Be, and Zr.

  2. Minimally refined biomass fuel

    DOEpatents

    Pearson, Richard K.; Hirschfeld, Tomas B.

    1984-01-01

    A minimally refined fluid composition, suitable as a fuel mixture and derived from biomass material, is comprised of one or more water-soluble carbohydrates such as sucrose, one or more alcohols having less than four carbons, and water. The carbohydrate provides the fuel source; water solubilizes the carbohydrates; and the alcohol aids in the combustion of the carbohydrate and reduces the vicosity of the carbohydrate/water solution. Because less energy is required to obtain the carbohydrate from the raw biomass than alcohol, an overall energy savings is realized compared to fuels employing alcohol as the primary fuel.

  3. Centrifugal main fuel pump

    SciTech Connect

    Cole, E.F.

    1986-08-26

    For a gas turbine power plant having a fuel supply and a fuel metering valve and variable geometry for the power plant including servo actuating mechanisms for the fuel metering valve and variable geometry, a fuel pumping system, is described to supply pressurized fuel for the servo actuating mechanisms and for the engine working fluid medium. The pumping system includes a centrifugal pump solely supplying the fuel to the fuel metering valve to be delivered to the power plant for its working fluid medium, a positive displacement pump in parallel with the centrifugal pump and solely to supply pressurized fuel to the servo actuating mechanisms for the fuel metering valve and for the variable geometry, and a boost pump means disposed in serial relationship with the positive displacement pump and the centrifugal pump for augmenting the pressure supplied by the positive displacement pump and the centrifugal pump during predetermined operating conditions of the power plant. The combined boost pump and centrifugal pump capability is sufficient to satisfy the vapor to liquid ratio requirements of the power during its entire operating envelope.

  4. Fuel injection pump

    SciTech Connect

    Luscomb, D.A.

    1984-05-22

    A fuel injection pump including a plunger and a piston movably disposed in a pumping chamber, means for initiating fuel injection and means for terminating fuel injection, the plunger periodically pressurizing fuel in a pressure chamber and the piston spaced from the plunger and allowing a metering chamber to fill with a metered quantity of fuel to be injected to an engine. The means for initiating injection comprises a pilot valve having a solenoid to selectively operate between either of two states and a control valve movable between first and second positions in response to the state of pilot valve, the first position filling the metering chamber with the metered quantity of fuel. The pilot valve determines the fuel quantity to be delivered to the engine relative to a signal from an electronic controller. An accumulator is pressurized during each cycle of the plunger to provide pressurized fuel during a metering phase. A variable orifice adjusts the rate of flow during the time fuel is being metered to metering chamber.

  5. Fuel injection pump

    SciTech Connect

    Iiyama, A.; Nishimura, T.

    1988-12-06

    This patent describes a fuel injection pump comprising: (a) engageable first and second cam members, the first cam member reciprocating axially as the first cam member moves angularly relative to the second cam member when the first and second cam members are in engagement; (b) means for urging the first cam member toward the second cam member to engage the first and second cam members; (c) a plunger connected to the first cam member for reciprocation with the first cam member, the plunger defining at least a part of a pumping chamber, the pumping chamber contracting and expanding as the plunger reciprocates; (d) means for allowing fuel to move into the pumping chamber as the pumping chamber expands in a fuel intake stroke; (e) means for allowing the fuel to move out of the pumping chamber as the pumping chamber contracts in a fuel compression stroke; and (f) means for resisting movement of the plunger in at least part of the fuel compression stroke and relieving resistance to the movement of the plunger in the fuel intake stroke wherein the resisting means comprises a piston slidably mounted on the plunger, a spring urging the piston to seat the piston on a shoulder on the plunger so that the piston reciprocates as the plunger reciprocates, wherein the piston is seated on the shoulder in the fuel compression stroke and separates from the shoulder against the force of the spring in the fuel intake stroke, a second fluid chamber at least partially defined by the piston.

  6. Fuel cell arrangement

    DOEpatents

    Isenberg, A.O.

    1987-05-12

    A fuel cell arrangement is provided wherein cylindrical cells of the solid oxide electrolyte type are arranged in planar arrays where the cells within a plane are parallel. Planes of cells are stacked with cells of adjacent planes perpendicular to one another. Air is provided to the interior of the cells through feed tubes which pass through a preheat chamber. Fuel is provided to the fuel cells through a channel in the center of the cell stack; the fuel then passes the exterior of the cells and combines with the oxygen-depleted air in the preheat chamber. 3 figs.

  7. Amtrak fuel consumption study

    SciTech Connect

    Hitz, J.

    1981-02-01

    This report documents a study of fuel consumption on National Railroad Passenger Corporation (Amtrak) trains and is part of an effort to determine effective ways of conserving fuel on the Amtrak system. The study was performed by the Transportation Systems Center (TSC). A series of 26 test runs were conducted on Amtrak trains operating between Boston, Massachusetts, and New Haven, Connecticut, to measure fuel consumption, trip time and other fuel-use-related parameters. The test data were analyzed and compared with results of the TSC Train Performance Simulator replicating the same operations.

  8. Fuel cell stack arrangements

    DOEpatents

    Kothmann, Richard E.; Somers, Edward V.

    1982-01-01

    Arrangements of stacks of fuel cells and ducts, for fuel cells operating with separate fuel, oxidant and coolant streams. An even number of stacks are arranged generally end-to-end in a loop. Ducts located at the juncture of consecutive stacks of the loop feed oxidant or fuel to or from the two consecutive stacks, each individual duct communicating with two stacks. A coolant fluid flows from outside the loop, into and through cooling channels of the stack, and is discharged into an enclosure duct formed within the loop by the stacks and seals at the junctures at the stacks.

  9. Rethinking nuclear fuel recycling.

    PubMed

    von Hippel, Frank N

    2008-05-01

    Spent nuclear fuel contains plutonium which can be extracted and used in new fuel. To reduce the amount of long-lived radioactive waste, the U.S. Department of Energy has proposed reprocessing spent fuel in this way and then "burning" the plutonium in special reactors. But reprocesssing is very expensive. Also, spent fuel emits lethal radiation, whereas separated plutonium can be handled easily. So reprocessing invites the possibility that terrorists might steal plutonium and construct an atom bormb. The authors argue against reprocessing and for storing the waste in casks until an underground repository is ready.

  10. Particle fuel diversion structure

    SciTech Connect

    Eshleman, R. D.

    1985-07-30

    A particle fuel burning furnace has an upper combustion chamber for holding a pile of particle fuel and burning the same from the bottom thereof. The furnace also includes a lower combustion chamber for after-burning combustible gases given off by the burning of solid fuel in the upper chamber and a series of spaced apart vertically-extending passageways arranged in a row and interconnecting the upper and lower chambers for communicating the combustible gases from the upper to the lower chamber. A first improved feature relates to a particle fuel delivery control device which operates an auger for filling the upper chamber with particle fuel to a desired level. A beam of light is transmitted and reflected between a photoelectric cell and reflector respectively of the device. When the particle fuel pile has grown in height during filling to the desired level the light beam is interrupted and filling is terminated. A second improved feature relates to a particle fuel diversion structure positioned in spaced relationship above and overlying the row of passageways. The structure forms a horizontal slot which extends laterally from the passageways which prevents particles of fuel from falling through the passageways and relocates the flame which burns the particle fuel pile from the bottom to a region away from the passageways.

  11. Alternative Fuels Infrastructure Development

    SciTech Connect

    Bloyd, Cary N.; Stork, Kevin

    2011-02-01

    This summary reviews the status of alternate transportation fuels development and utilization in Thailand. Thailand has continued to work to promote increased consumption of gasohol especially for highethanol content fuels like E85. The government has confirmed its effort to draw up incentives for auto makers to invest in manufacturing E85-compatible vehicles in the country. An understanding of the issues and experiences associated with the introduction of alternative fuels in other countries can help the US in anticipation potential problems as it introduces new automotive fuels.

  12. NUCLEAR REACTOR FUEL ELEMENT

    DOEpatents

    Anderson, W.F.; Tellefson, D.R.; Shimazaki, T.T.

    1962-04-10

    A plate type fuel element which is particularly useful for organic cooled reactors is described. Generally, the fuel element comprises a plurality of fissionable fuel bearing plates held in spaced relationship by a frame in which the plates are slidably mounted in grooves. Clearance is provided in the grooves to allow the plates to expand laterally. The plates may be rigidly interconnected but are floatingly supported at their ends within the frame to allow for longi-tudinal expansion. Thus, this fuel element is able to withstand large temperature differentials without great structural stresses. (AEC)

  13. Energy: Reimagine Fuel Cells

    SciTech Connect

    Lemmon, John P.

    2015-09-24

    New types of fuel cell on the horizon could eliminate the need for such trade-offs and ease the integration of renewables into the grid. Currently, fuel cells are used to generate only electricity and heat. They can be modified to store energy and produce liquid fuels such as methanol, thanks to breakthroughs in materials and designs. Developing fuel cells with a battery mode is one focus of the programme I direct at the US Advanced Research Projects Agency–Energy (ARPA-E). I lead 13 projects across academia, industry and national laboratories.

  14. Thorium fueled reactor

    NASA Astrophysics Data System (ADS)

    Sipaun, S.

    2017-01-01

    Current development in thorium fueled reactors shows that they can be designed to operate in the fast or thermal spectrum. The thorium/uranium fuel cycle converts fertile thorium-232 into fissile uranium-233, which fissions and releases energy. This paper analyses the characteristics of thorium fueled reactors and discusses the thermal reactor option. It is found that thorium fuel can be utilized in molten salt reactors through many configurations and designs. A balanced assessment on the feasibility of adopting one reactor technology versus another could lead to optimized benefits of having thorium resource.

  15. Fuel Cell Demonstration Program

    SciTech Connect

    Gerald Brun

    2006-09-15

    In an effort to promote clean energy projects and aid in the commercialization of new fuel cell technologies the Long Island Power Authority (LIPA) initiated a Fuel Cell Demonstration Program in 1999 with six month deployments of Proton Exchange Membrane (PEM) non-commercial Beta model systems at partnering sites throughout Long Island. These projects facilitated significant developments in the technology, providing operating experience that allowed the manufacturer to produce fuel cells that were half the size of the Beta units and suitable for outdoor installations. In 2001, LIPA embarked on a large-scale effort to identify and develop measures that could improve the reliability and performance of future fuel cell technologies for electric utility applications and the concept to establish a fuel cell farm (Farm) of 75 units was developed. By the end of October of 2001, 75 Lorax 2.0 fuel cells had been installed at the West Babylon substation on Long Island, making it the first fuel cell demonstration of its kind and size anywhere in the world at the time. Designed to help LIPA study the feasibility of using fuel cells to operate in parallel with LIPA's electric grid system, the Farm operated 120 fuel cells over its lifetime of over 3 years including 3 generations of Plug Power fuel cells (Lorax 2.0, Lorax 3.0, Lorax 4.5). Of these 120 fuel cells, 20 Lorax 3.0 units operated under this Award from June 2002 to September 2004. In parallel with the operation of the Farm, LIPA recruited government and commercial/industrial customers to demonstrate fuel cells as on-site distributed generation. From December 2002 to February 2005, 17 fuel cells were tested and monitored at various customer sites throughout Long Island. The 37 fuel cells operated under this Award produced a total of 712,635 kWh. As fuel cell technology became more mature, performance improvements included a 1% increase in system efficiency. Including equipment, design, fuel, maintenance, installation

  16. Fuel processing device

    DOEpatents

    Ahluwalia, Rajesh K.; Ahmed, Shabbir; Lee, Sheldon H. D.

    2011-08-02

    An improved fuel processor for fuel cells is provided whereby the startup time of the processor is less than sixty seconds and can be as low as 30 seconds, if not less. A rapid startup time is achieved by either igniting or allowing a small mixture of air and fuel to react over and warm up the catalyst of an autothermal reformer (ATR). The ATR then produces combustible gases to be subsequently oxidized on and simultaneously warm up water-gas shift zone catalysts. After normal operating temperature has been achieved, the proportion of air included with the fuel is greatly diminished.

  17. Nuclear fuel pin scanner

    DOEpatents

    Bramblett, Richard L.; Preskitt, Charles A.

    1987-03-03

    Systems and methods for inspection of nuclear fuel pins to determine fiss loading and uniformity. The system includes infeed mechanisms which stockpile, identify and install nuclear fuel pins into an irradiator. The irradiator provides extended activation times using an approximately cylindrical arrangement of numerous fuel pins. The fuel pins can be arranged in a magazine which is rotated about a longitudinal axis of rotation. A source of activating radiation is positioned equidistant from the fuel pins along the longitudinal axis of rotation. The source of activating radiation is preferably oscillated along the axis to uniformly activate the fuel pins. A detector is provided downstream of the irradiator. The detector uses a plurality of detector elements arranged in an axial array. Each detector element inspects a segment of the fuel pin. The activated fuel pin being inspected in the detector is oscillated repeatedly over a distance equal to the spacing between adjacent detector elements, thereby multiplying the effective time available for detecting radiation emissions from the activated fuel pin.

  18. Cell module and fuel conditioner development

    NASA Technical Reports Server (NTRS)

    Hoover, D. Q., Jr.

    1981-01-01

    The design features and plans for fabrication of Stacks 564 and 800 are described. The results of the OS/IES loop testing of Stack 562, endurance testing of Stack 560 and the post test analysis of Stack 561 are reported. Progress on construction and modification of the fuel cell test facilities and the 10 kW reformer test station is described. Efforts to develop the technical data base for the fuel conditioning system included vendor contacts, packed bed heat transfer tests, development of the BOLTAR computer program, and work on the detailed design of the 10 kW reformer are described.

  19. Solid oxide fuel cell generator

    DOEpatents

    Di Croce, A. Michael; Draper, Robert

    1993-11-02

    A solid oxide fuel cell generator has a plenum containing at least two rows of spaced apart, annular, axially elongated fuel cells. An electrical conductor extending between adjacent rows of fuel cells connects the fuel cells of one row in parallel with each other and in series with the fuel cells of the adjacent row.

  20. Fuel cell generator energy dissipator

    DOEpatents

    Veyo, Stephen Emery; Dederer, Jeffrey Todd; Gordon, John Thomas; Shockling, Larry Anthony

    2000-01-01

    An apparatus and method are disclosed for eliminating the chemical energy of fuel remaining in a fuel cell generator when the electrical power output of the fuel cell generator is terminated. During a generator shut down condition, electrically resistive elements are automatically connected across the fuel cell generator terminals in order to draw current, thereby depleting the fuel

  1. Fuel Cells: Reshaping the Future

    ERIC Educational Resources Information Center

    Toay, Leo

    2004-01-01

    In conjunction with the FreedomCAR (Cooperative Automotive Research) and Fuel Initiative, President George W. Bush has pledged nearly two billion dollars for fuel cell research. Chrysler, Ford, and General Motors have unveiled fuel cell demonstration vehicles, and all three of these companies have invested heavily in fuel cell research. Fuel cell…

  2. Fuel Cells: Reshaping the Future

    ERIC Educational Resources Information Center

    Toay, Leo

    2004-01-01

    In conjunction with the FreedomCAR (Cooperative Automotive Research) and Fuel Initiative, President George W. Bush has pledged nearly two billion dollars for fuel cell research. Chrysler, Ford, and General Motors have unveiled fuel cell demonstration vehicles, and all three of these companies have invested heavily in fuel cell research. Fuel cell…

  3. Fuel cycle for a fusion neutron source

    NASA Astrophysics Data System (ADS)

    Ananyev, S. S.; Spitsyn, A. V.; Kuteev, B. V.

    2015-12-01

    The concept of a tokamak-based stationary fusion neutron source (FNS) for scientific research (neutron diffraction, etc.), tests of structural materials for future fusion reactors, nuclear waste transmutation, fission reactor fuel production, and control of subcritical nuclear systems (fusion-fission hybrid reactor) is being developed in Russia. The fuel cycle system is one of the most important systems of FNS that provides circulation and reprocessing of the deuterium-tritium fuel mixture in all fusion reactor systems: the vacuum chamber, neutral injection system, cryogenic pumps, tritium purification system, separation system, storage system, and tritium-breeding blanket. The existing technologies need to be significantly upgraded since the engineering solutions adopted in the ITER project can be only partially used in the FNS (considering the capacity factor higher than 0.3, tritium flow up to 200 m3Pa/s, and temperature of reactor elements up to 650°C). The deuterium-tritium fuel cycle of the stationary FNS is considered. The TC-FNS computer code developed for estimating the tritium distribution in the systems of FNS is described. The code calculates tritium flows and inventory in tokamak systems (vacuum chamber, cryogenic pumps, neutral injection system, fuel mixture purification system, isotope separation system, tritium storage system) and takes into account tritium loss in the fuel cycle due to thermonuclear burnup and β decay. For the two facility versions considered, FNS-ST and DEMO-FNS, the amount of fuel mixture needed for uninterrupted operation of all fuel cycle systems is 0.9 and 1.4 kg, consequently, and the tritium consumption is 0.3 and 1.8 kg per year, including 35 and 55 g/yr, respectively, due to tritium decay.

  4. Fuel cycle for a fusion neutron source

    SciTech Connect

    Ananyev, S. S. Spitsyn, A. V. Kuteev, B. V.

    2015-12-15

    The concept of a tokamak-based stationary fusion neutron source (FNS) for scientific research (neutron diffraction, etc.), tests of structural materials for future fusion reactors, nuclear waste transmutation, fission reactor fuel production, and control of subcritical nuclear systems (fusion–fission hybrid reactor) is being developed in Russia. The fuel cycle system is one of the most important systems of FNS that provides circulation and reprocessing of the deuterium–tritium fuel mixture in all fusion reactor systems: the vacuum chamber, neutral injection system, cryogenic pumps, tritium purification system, separation system, storage system, and tritium-breeding blanket. The existing technologies need to be significantly upgraded since the engineering solutions adopted in the ITER project can be only partially used in the FNS (considering the capacity factor higher than 0.3, tritium flow up to 200 m{sup 3}Pa/s, and temperature of reactor elements up to 650°C). The deuterium–tritium fuel cycle of the stationary FNS is considered. The TC-FNS computer code developed for estimating the tritium distribution in the systems of FNS is described. The code calculates tritium flows and inventory in tokamak systems (vacuum chamber, cryogenic pumps, neutral injection system, fuel mixture purification system, isotope separation system, tritium storage system) and takes into account tritium loss in the fuel cycle due to thermonuclear burnup and β decay. For the two facility versions considered, FNS-ST and DEMO-FNS, the amount of fuel mixture needed for uninterrupted operation of all fuel cycle systems is 0.9 and 1.4 kg, consequently, and the tritium consumption is 0.3 and 1.8 kg per year, including 35 and 55 g/yr, respectively, due to tritium decay.

  5. 33. Coal Fuel Elevator (diagonal in foreground), Fuel Elevator (left), ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    33. Coal Fuel Elevator (diagonal in foreground), Fuel Elevator (left), Fuel Storage Bins (center), and Power Plant (right) Photographs taken by Joseph E.B. Elliot - Huber Coal Breaker, 101 South Main Street, Ashley, Luzerne County, PA

  6. Fuel Cells Vehicle Systems Analysis (Fuel Cell Freeze Investigation)

    SciTech Connect

    Pesaran, A.; Kim, G.; Markel, T.; Wipke, K.

    2005-05-01

    Presentation on Fuel Cells Vehicle Systems Analysis (Fuel Cell Freeze Investigation) for the 2005 Hydrogen, Fuel Cells & Infrastructure Technologies Program Annual Review held in Arlington, Virginia on May 23-26, 2005.

  7. CERDEC Fuel Cell Team: Military Transitions for Soldier Fuel Cells

    DTIC Science & Technology

    2008-10-27

    Fuel Cell (DMFC) (PEO Soldier) Samsung: 20W DMFC (CRADA) General Atomics & Jadoo: 50W Ammonia Borane Fueled PEMFC Current Fuel Cell Team Efforts...Continued Ardica: 20W Wearable PEMFC operating on Chemical Hydrides Spectrum Brands w/ Rayovac: Hydrogen Generators and Alkaline Fuel Cells for AA...100W Ammonia Borane fueled PEMFC Ultralife: 150W sodium borohydride fueled PEMFC Protonex: 250W RMFC and Power Manager (ARO) NanoDynamics: 250W SOFC

  8. Future of Fuel Savings

    NASA Technical Reports Server (NTRS)

    Hughes, David

    2004-01-01

    Using automation to free up controllers for more strategic management of air traffic is one approach being studied by NASA as it seeks to boost airspace system capacity and efficiency, thereby saving fuel. Heinz Erzberger, a NASA Ames Research Center senior scientist, says the Advanced Airspace Concept (AAC) has been studied for several years. It could increase efficiency 15% by providing optimal routes that cut airlines direct operating costs. A 25% increase in landings on existing runways could follow an important benefit. AAC is one of the efforts to be reviewed by the Joint Planning and Development Organization, an FAA-led initiative by six federal agencies to redesign the U.S. air transportation system by 2025. The main goal is to triple air traffic capacity within 20 years to avert the sort of gridlock that would make fuel consumption only one of many travel nightmares. The automated system approach would allow aircraft to fly optimal trajectories. A trajectory would be defined in the standard three dimensions and eventually include the fourth, time. The management of air traffic by the data-linked exchange of trajectories would start at high altitude and eventually move down to lower altitudes. The automated concept is an outgrowth of the type of tools developed by NASA for use by FAA controllers in managing traffic flows over the years, including ones that optimize routings for the best fuel burn. But AAC would push automation further to reduce workload so controllers can focus on "solving strategic control problems, managing traffic flow during changing weather and ... other unusal events." One key component, the automated trajectory server (ATS), is a ground systems that would rely on software to manage flight path requests from aircrews and controllers. But, Erzberger acknowledges, "The FAA's current plan for upgrades to air traffic services does not include [allowing] the future ground system to issue separation-critical clearances of trajectory changes

  9. Future of Fuel Savings

    NASA Technical Reports Server (NTRS)

    Hughes, David

    2004-01-01

    Using automation to free up controllers for more strategic management of air traffic is one approach being studied by NASA as it seeks to boost airspace system capacity and efficiency, thereby saving fuel. Heinz Erzberger, a NASA Ames Research Center senior scientist, says the Advanced Airspace Concept (AAC) has been studied for several years. It could increase efficiency 15% by providing optimal routes that cut airlines direct operating costs. A 25% increase in landings on existing runways could follow an important benefit. AAC is one of the efforts to be reviewed by the Joint Planning and Development Organization, an FAA-led initiative by six federal agencies to redesign the U.S. air transportation system by 2025. The main goal is to triple air traffic capacity within 20 years to avert the sort of gridlock that would make fuel consumption only one of many travel nightmares. The automated system approach would allow aircraft to fly optimal trajectories. A trajectory would be defined in the standard three dimensions and eventually include the fourth, time. The management of air traffic by the data-linked exchange of trajectories would start at high altitude and eventually move down to lower altitudes. The automated concept is an outgrowth of the type of tools developed by NASA for use by FAA controllers in managing traffic flows over the years, including ones that optimize routings for the best fuel burn. But AAC would push automation further to reduce workload so controllers can focus on "solving strategic control problems, managing traffic flow during changing weather and ... other unusal events." One key component, the automated trajectory server (ATS), is a ground systems that would rely on software to manage flight path requests from aircrews and controllers. But, Erzberger acknowledges, "The FAA's current plan for upgrades to air traffic services does not include [allowing] the future ground system to issue separation-critical clearances of trajectory changes

  10. Methodology for Formulating Diesel Surrogate Fuels with Accurate Compositional, Ignition-Quality, and Volatility Characteristics

    SciTech Connect

    Mueller, C. J.; Cannella, W. J.; Bruno, T. J.; Bunting, B.; Dettman, H. D.; Franz, J. A.; Huber, M. L.; Natarajan, M.; Pitz, W. J.; Ratcliff, M. A.; Wright, K.

    2012-06-21

    In this study, a novel approach was developed to formulate surrogate fuels having characteristics that are representative of diesel fuels produced from real-world refinery streams. Because diesel fuels typically consist of hundreds of compounds, it is difficult to conclusively determine the effects of fuel composition on combustion properties. Surrogate fuels, being simpler representations of these practical fuels, are of interest because they can provide a better understanding of fundamental fuel-composition and property effects on combustion and emissions-formation processes in internal-combustion engines. In addition, the application of surrogate fuels in numerical simulations with accurate vaporization, mixing, and combustion models could revolutionize future engine designs by enabling computational optimization for evolving real fuels. Dependable computational design would not only improve engine function, it would do so at significant cost savings relative to current optimization strategies that rely on physical testing of hardware prototypes. The approach in this study utilized the state-of-the-art techniques of {sup 13}C and {sup 1}H nuclear magnetic resonance spectroscopy and the advanced distillation curve to characterize fuel composition and volatility, respectively. The ignition quality was quantified by the derived cetane number. Two well-characterized, ultra-low-sulfur No.2 diesel reference fuels produced from refinery streams were used as target fuels: a 2007 emissions certification fuel and a Coordinating Research Council (CRC) Fuels for Advanced Combustion Engines (FACE) diesel fuel. A surrogate was created for each target fuel by blending eight pure compounds. The known carbon bond types within the pure compounds, as well as models for the ignition qualities and volatilities of their mixtures, were used in a multiproperty regression algorithm to determine optimal surrogate formulations. The predicted and measured surrogate-fuel properties were

  11. Methodology for Formulating Diesel Surrogate Fuels with Accurate Compositional, Ignition-Quality, and Volatility Characteristics

    SciTech Connect

    Mueller, Charles J.; Cannella, William J.; Bruno, Thomas J.; Bunting, Bruce; Dettman, Heather D.; Franz, James A.; Huber, Marcia L.; Natarajan, Mani; Pitz, William J.; Ratcliff, Matthew A.; Wright, Ken

    2012-06-21

    In this study, a novel approach was developed to formulate surrogate fuels having characteristics that are representative of diesel fuels produced from real-world refinery streams. Because diesel fuels typically consist of hundreds of compounds, it is difficult to conclusively determine the effects of fuel composition on combustion properties. Surrogate fuels, being simpler representations of these practical fuels, are of interest because they can provide a better understanding of fundamental fuel-composition and property effects on combustion and emissions-formation processes in internal-combustion engines. In addition, the application of surrogate fuels in numerical simulations with accurate vaporization, mixing, and combustion models could revolutionize future engine designs by enabling computational optimization for evolving real fuels. Dependable computational design would not only improve engine function, it would do so at significant cost savings relative to current optimization strategies that rely on physical testing of hardware prototypes. The approach in this study utilized the state-of-the-art techniques of 13C and 1H nuclear magnetic resonance spectroscopy and the advanced distillation curve to characterize fuel composition and volatility, respectively. The ignition quality was quantified by the derived cetane number. Two well-characterized, ultra-low-sulfur #2 diesel reference fuels produced from refinery streams were used as target fuels: a 2007 emissions certification fuel and a Coordinating Research Council (CRC) Fuels for Advanced Combustion Engines (FACE) diesel fuel. A surrogate was created for each target fuel by blending eight pure compounds. The known carbon bond types within the pure compounds, as well as models for the ignition qualities and volatilities of their mixtures, were used in a multiproperty regression algorithm to determine optimal surrogate formulations. The predicted and measured surrogate-fuel properties were quantitatively

  12. Methodology for Formulating Diesel Surrogate Fuels with Accurate Compositional, Ignition-Quality, and Volatility Characteristics

    DOE PAGES

    Mueller, Charles J.; Cannella, William J.; Bruno, Thomas J.; ...

    2012-05-22

    In this study, a novel approach was developed to formulate surrogate fuels having characteristics that are representative of diesel fuels produced from real-world refinery streams. Because diesel fuels typically consist of hundreds of compounds, it is difficult to conclusively determine the effects of fuel composition on combustion properties. Surrogate fuels, being simpler representations of these practical fuels, are of interest because they can provide a better understanding of fundamental fuel-composition and property effects on combustion and emissions-formation processes in internal-combustion engines. In addition, the application of surrogate fuels in numerical simulations with accurate vaporization, mixing, and combustion models could revolutionizemore » future engine designs by enabling computational optimization for evolving real fuels. Dependable computational design would not only improve engine function, it would do so at significant cost savings relative to current optimization strategies that rely on physical testing of hardware prototypes. The approach in this study utilized the state-of-the-art techniques of 13C and 1H nuclear magnetic resonance spectroscopy and the advanced distillation curve to characterize fuel composition and volatility, respectively. The ignition quality was quantified by the derived cetane number. Two well-characterized, ultra-low-sulfur #2 diesel reference fuels produced from refinery streams were used as target fuels: a 2007 emissions certification fuel and a Coordinating Research Council (CRC) Fuels for Advanced Combustion Engines (FACE) diesel fuel. A surrogate was created for each target fuel by blending eight pure compounds. The known carbon bond types within the pure compounds, as well as models for the ignition qualities and volatilities of their mixtures, were used in a multiproperty regression algorithm to determine optimal surrogate formulations. The predicted and measured surrogate-fuel properties were

  13. Vehicle and Fuel Emissions Testing

    EPA Pesticide Factsheets

    EPA's National Vehicle and Fuel Emissions Laboratory's primary responsibilities include: evaluating emission control technology; testing vehicles, engines and fuels; and determining compliance with federal emissions and fuel economy standards.

  14. Isoprenoid based alternative diesel fuel

    DOEpatents

    Lee, Taek Soon; Peralta-Yahya, Pamela; Keasling, Jay D.

    2015-08-18

    Fuel compositions are provided comprising a hydrogenation product of a monocyclic sesquiterpene (e.g., hydrogenated bisabolene) and a fuel additive. Methods of making and using the fuel compositions are also disclosed. ##STR00001##

  15. The Fuel Schools Use

    ERIC Educational Resources Information Center

    CEFP Journal, 1977

    1977-01-01

    Nearly 3,000 U.S. school districts reported to the Federal Energy Administration on comparative fuel costs and use in 1972-3 and 1974-5. The FEA survey represents the first major national effort to assess the impact of rising fuel costs on education. (Author/MLF)

  16. Solar Fuel Generator

    NASA Technical Reports Server (NTRS)

    Lewis, Nathan S. (Inventor); West, William C. (Inventor)

    2017-01-01

    The disclosure provides conductive membranes for water splitting and solar fuel generation. The membranes comprise an embedded semiconductive/photoactive material and an oxygen or hydrogen evolution catalyst. Also provided are chassis and cassettes containing the membranes for use in fuel generation.

  17. The Fuel Schools Use

    ERIC Educational Resources Information Center

    CEFP Journal, 1977

    1977-01-01

    Nearly 3,000 U.S. school districts reported to the Federal Energy Administration on comparative fuel costs and use in 1972-3 and 1974-5. The FEA survey represents the first major national effort to assess the impact of rising fuel costs on education. (Author/MLF)

  18. Alternative Fuels in Transportation

    ERIC Educational Resources Information Center

    Kouroussis, Denis; Karimi, Shahram

    2006-01-01

    The realization of dwindling fossil fuel supplies and their adverse environmental impacts has accelerated research and development activities in the domain of renewable energy sources and technologies. Global energy demand is expected to rise during the next few decades, and the majority of today's energy is based on fossil fuels. Alternative…

  19. Fuel injection nozzle

    SciTech Connect

    Kato, M.; Nakatsuka, H.; Tojo, S.; Arai, K.

    1986-12-09

    A fuel injection nozzle is described which is adapted to be connected to a fuel injection pump and which serves to inject fuel into a combustion chamber in an internal combustion engine. The nozzle consists of: a body in which a suction passage and an accumulating chamber are defined, the suction passage being adapted to be connected with a fuel injection pump and the accumulating chamber being connected with the suction passage; a non-return valve means for allowing the fuel to flow from the suction passage to the accumulating chamber but prohibiting the fuel from flowing from the accumulating chamber to the suction passage; a needle valve means for injecting the fuel stored in the accumulating chamber into a combustion chamber in an engine, the needle valve means including a nozzle needle arranged coaxially and in series with the valve with end portions thereof being adjacent; a damping plunger coaxially fitted into the valve member in the manner that the damping plunger is urged toward the nozzle needle and has one end protruding into the damping chamber and engageable by the nozzle needle, throttle means disposed in the through hole in the damping plunger, for restricting the fuel flow between the damping chamber and the connector recess.

  20. Nanofluidic fuel cell

    NASA Astrophysics Data System (ADS)

    Lee, Jin Wook; Kjeang, Erik

    2013-11-01

    Fuel cells are gaining momentum as a critical component in the renewable energy mix for stationary, transportation, and portable power applications. State-of-the-art fuel cell technology benefits greatly from nanotechnology applied to nanostructured membranes, catalysts, and electrodes. However, the potential of utilizing nanofluidics for fuel cells has not yet been explored, despite the significant opportunity of harnessing rapid nanoscale reactant transport in close proximity to the reactive sites. In the present article, a nanofluidic fuel cell that utilizes fluid flow through nanoporous media is conceptualized and demonstrated for the first time. This transformative concept captures the advantages of recently developed membraneless and catalyst-free fuel cell architectures paired with the enhanced interfacial contact area enabled by nanofluidics. When compared to previously reported microfluidic fuel cells, the prototype nanofluidic fuel cell demonstrates increased surface area, reduced activation overpotential, superior kinetic characteristics, and moderately enhanced fuel cell performance in the high cell voltage regime with up to 14% higher power density. However, the expected mass transport benefits in the high current density regime were constrained by high ohmic cell resistance, which could likely be resolved through future optimization studies.

  1. Fuel temperature counter

    Treesearch

    John R. Murray; Charles W. Philpot

    1963-01-01

    Fuel temperature is and has always been difficult to measure. To understand better the problem of fire and fire weather behavior, it is important to measure this variable. We have developed for field use a new fuel temperature counter which can be used to obtain such measurements quickly and easily. This electronic recording instrument is easy to construct and operate...

  2. Fuel cells: Operating flexibly

    NASA Astrophysics Data System (ADS)

    Lee, Young Moo

    2016-09-01

    Fuel cells typically function well only in rather limited temperature and humidity ranges. Now, a proton exchange membrane consisting of ion pair complexes is shown to enable improved fuel cell performance under a wide range of conditions that are unattainable with conventional approaches.

  3. Solar fuel generator

    DOEpatents

    Lewis, Nathan S.; West, William C.

    2017-01-17

    The disclosure provides conductive membranes for water splitting and solar fuel generation. The membranes comprise an embedded semiconductive/photoactive material and an oxygen or hydrogen evolution catalyst. Also provided are chassis and cassettes containing the membranes for use in fuel generation.

  4. Tilted fuel cell apparatus

    DOEpatents

    Cooper, John F.; Cherepy, Nerine; Krueger, Roger L.

    2005-04-12

    Bipolar, tilted embodiments of high temperature, molten electrolyte electrochemical cells capable of directly converting carbon fuel to electrical energy are disclosed herein. The bipolar, tilted configurations minimize the electrical resistance between one cell and others connected in electrical series. The tilted configuration also allows continuous refueling of carbon fuel.

  5. NEUTRONIC REACTOR FUEL ELEMENT

    DOEpatents

    Gurinsky, D.H.; Powell, R.W.; Fox, M.

    1959-11-24

    A nuclear fuel element comprising a plurality of nuclear fuel bearing strips is presented. The strips are folded along their longitudinal axes to an angle of about 60 deg and are secured at each end by ferrule to form an elongated assembly suitable for occupying a cylindrical coolant channel.

  6. PLATINUM AND FUEL CELLS

    EPA Science Inventory

    Platinum requirements for fuel cell vehicles (FCVS) have been identified as a concern and possible problem with FCV market penetration. Platinum is a necessary component of the electrodes of fuel cell engines that power the vehicles. The platinum is deposited on porous electrodes...

  7. NEUTRONIC REACTOR FUEL ELEMENT

    DOEpatents

    Horning, W.A.; Lanning, D.D.; Donahue, D.J.

    1959-10-01

    A fuel slug for a reactor which acts as a safety device is described. The fuel slug is an aluminum tube with a foil lining the inside surface of the tube, the foil being fabricated of uranium in a lead matrix.

  8. Aminoamide fuel detergents

    SciTech Connect

    Bonazza, B.R.; Holtz, H.D.

    1981-02-10

    A detergent additive aminoamide, prepared by reacting a polycarboxylic amino acid with alkylamines, is combined into fuel for an internal combustion engine or lubricating oil as a composition suitable for reducing deposits in an internal combustion engine. In an embodiment of the invention, the aminoamide is further combined with a sulfonic acid to obtain a fuel detergent of improved operability.

  9. Imidazoline fuel detergents

    SciTech Connect

    Bonazza, B. R.; Holtz, H. D.

    1981-01-27

    A detergent additive imidazoline prepared by reacting carboxylic acid with polyamine is combined into fuel for an internal combustion engine or lubricating oil as a composition suitable for reducing deposits in an internal combustion engine. In an embodiment of the invention, the imidazoline is further combined with a sulfonic acid to obtain a fuel detergent of improved operability.

  10. Guide to fuel suppliers

    SciTech Connect

    Not Available

    1992-10-01

    This article is a directory of fuel suppliers to the electric power industry. The directory contains the company name, address, telephone and FAX numbers, contact person and a description of the fuels and services offered by the companies and their market areas. The directory's scope covers North America.

  11. CEROLYTE FUEL CELL.

    DTIC Science & Technology

    construction of a power plant for space. A 50-watt cerolyte battery will be constructed and a 500-watt fuel - cell power plant will be designed. Research...evaluation of a 500-watt cerolyte fuel - cell power system for space. During the first quarter work has been concentrated in the first two areas.

  12. Fuel Cells for Society

    NASA Technical Reports Server (NTRS)

    1999-01-01

    Through a SBIR contract with Lewis Research Center, ElectroChem, Inc. developed a hydrogen/oxygen fuel cell. The objective for Lewis Research Center's collaboration with ElectroChem was to develop a fuel cell system that could deliver 200-W (minimum) approximately to 10kWh of electrical energy.

  13. Transportation fuels: Desulfurizing diesel

    NASA Astrophysics Data System (ADS)

    Lamonier, Carole

    2017-02-01

    Transportation fuels such as diesel contain organosulfur molecules that, when combusted, form sulfur oxides that are toxic and poison vehicles' catalytic convertors. Now, a method is demonstrated that can reduce the sulfur concentration of diesel fuel to very low levels at low temperatures and pressures.

  14. NUCLEAR REACTOR FUEL ELEMENT

    DOEpatents

    Currier, E.L. Jr.; Nicklas, J.H.

    1963-06-11

    A fuel plate is designed for incorporation into control rods of the type utilized in high-flux test reactors. The fuel plate is designed so that the portion nearest the poison section of the control rod contains about one-half as much fissionable material as in the rest of the plate, thereby eliminating dangerous flux peaking in that portion. (AEC)

  15. Fuels Combustion Research.

    DTIC Science & Technology

    1982-07-30

    the more complex fuels I1. Extensive flow reactor data over the temperature range 1110-1235 and at 1 atm suggested that the overall pyrolyses rate...differently than the aliphatic fuels and more Importantly during Its pyrolyses step forms butadiene and vinyl acetylene, other important precursors to

  16. CO2-Neutral Fuels

    NASA Astrophysics Data System (ADS)

    Goede, Adelbert; van de Sanden, Richard

    2016-06-01

    Mimicking the biogeochemical cycle of System Earth, synthetic hydrocarbon fuels are produced from recycled CO2 and H2O powered by renewable energy. Recapturing CO2 after use closes the carbon cycle, rendering the fuel cycle CO2 neutral. Non-equilibrium molecular CO2 vibrations are key to high energy efficiency.

  17. PLATINUM AND FUEL CELLS

    EPA Science Inventory

    Platinum requirements for fuel cell vehicles (FCVS) have been identified as a concern and possible problem with FCV market penetration. Platinum is a necessary component of the electrodes of fuel cell engines that power the vehicles. The platinum is deposited on porous electrodes...

  18. Alternative Fuels in Transportation

    ERIC Educational Resources Information Center

    Kouroussis, Denis; Karimi, Shahram

    2006-01-01

    The realization of dwindling fossil fuel supplies and their adverse environmental impacts has accelerated research and development activities in the domain of renewable energy sources and technologies. Global energy demand is expected to rise during the next few decades, and the majority of today's energy is based on fossil fuels. Alternative…

  19. Improved hybrid rocket fuel

    NASA Technical Reports Server (NTRS)

    Dean, David L.

    1995-01-01

    McDonnell Douglas Aerospace, as part of its Independent R&D, has initiated development of a clean burning, high performance hybrid fuel for consideration as an alternative to the solid rocket thrust augmentation currently utilized by American space launch systems including Atlas, Delta, Pegasus, Space Shuttle, and Titan. It could also be used in single stage to orbit or as the only propulsion system in a new launch vehicle. Compared to solid propellants based on aluminum and ammonium perchlorate, this fuel is more environmentally benign in that it totally eliminates hydrogen chloride and aluminum oxide by products, producing only water, hydrogen, nitrogen, carbon oxides, and trace amounts of nitrogen oxides. Compared to other hybrid fuel formulations under development, this fuel is cheaper, denser, and faster burning. The specific impulse of this fuel is comparable to other hybrid fuels and is between that of solids and liquids. The fuel also requires less oxygen than similar hybrid fuels to produce maximum specific impulse, thus reducing oxygen delivery system requirements.

  20. Mixed oxide fuel development

    SciTech Connect

    Leggett, R.D.; Omberg, R.P.

    1987-05-08

    This paper describes the success of the ongoing mixed-oxide fuel development program in the United States aimed at qualifying an economical fuel system for liquid metal cooled reactors. This development has been the cornerstone of the US program for the past 20 years and has proceeded in a deliberate and highly disciplined fashion with high emphasis on fuel reliability and operational safety as major features of an economical fuel system. The program progresses from feature testing in EBR-II to qualifying full size components in FFTF under fully prototypic conditions to establish a basis for extending allowable lifetimes. The development program started with the one year (300 EFPD) core, which is the FFTF driver fuel, continued with the demonstration of a two year (600 EFPD) core and is presently evaluating a three year (900 EFPD) fuel system. All three of these systems, consistent with other LMR fuel programs around the world, use fuel pellets gas bonded to a cladding tube that is assembled into a bundle and fitted into a wrapper tube or duct for ease of insertion into a core. The materials of construction progressed from austenitic CW 316 SS to lower swelling austenitic D9 to non swelling ferritic/martensitic HT9. 6 figs., 2 tabs.

  1. Metallic fuels handbook

    SciTech Connect

    Hofman, G. L.; Leibowitz, L.; Kramer, J. M.; Billone, M. C.; Koenig, J. F.

    1985-11-01

    This compilation of Thermophysical and Mechanical Properties of certain metallic fuels is meant to be used as a common source of data in work related to the Integral Fast Reactor. This handbook focuses on the two fuel compositions chosen for the IFR; namely, Uranium-Zirconium and Uranium-Plutonium-Zirconium.

  2. A solution to the problem of optimizing the fuel bias for a liquid propellant rocket by an application of the central limit theorem

    NASA Technical Reports Server (NTRS)

    Viera, W. J.

    1974-01-01

    A method of determining the fuel bias for a bipropellant liquid rocket that minimizes outage associated penalties on payload potential is presented. A fuel bias so derived is normally called the optimum fuel bias. The subjects discussed are: (1) probability density function of outage, (2) computer program listing, and (3) choosing the optimum fuel bias.

  3. Computers and Computer Resources.

    ERIC Educational Resources Information Center

    Bitter, Gary

    1980-01-01

    This resource directory provides brief evaluative descriptions of six popular home computers and lists selected sources of educational software, computer books, and magazines. For a related article on microcomputers in the schools, see p53-58 of this journal issue. (SJL)

  4. NUCLEAR FUEL MATERIAL

    DOEpatents

    Goeddel, W.V.

    1962-06-26

    An improved method is given for making the carbides of nuclear fuel material. The metal of the fuel material, which may be a fissile and/or fertile material, is transformed into a silicide, after which the silicide is comminuted to the desired particle size. This silicide is then carburized at an elevated temperature, either above or below the melting point of the silicide, to produce an intimate mixture of the carbide of the fuel material and the carbide of silicon. This mixture of the fuel material carbide and the silicon carbide is relatively stable in the presence of moisture and does not exhibit the highly reactive surface condition which is observed with fuel material carbides made by most other known methods. (AEC)

  5. Assessment of automotive fuels

    NASA Astrophysics Data System (ADS)

    Isenberg, G.

    Energy demand all over the world increases steadily and, within the next decades, is almost completely met by fossil fuels. This poses increasing pressure on oil supply and reserves. Concomitant is the concern about environmental pollution, especially by carbon dioxide from fossil fuel combustion, with the risk of global warming. Environmental well-being requires a modified mix of energy sources to emit less carbon dioxide, starting with a move to natural gas and ending with the market penetration of renewable energies. Efforts should focus on advanced oil and gas production and processing technologies and on regeneratively produced fuels like hydrogen or bio-fuels as well. Within the framework of an industrial initiative in Germany, a process of defining one or two alternative fuels was started, to bring them into the market within the next years.

  6. Jet Fuel Thermal Stability

    NASA Technical Reports Server (NTRS)

    Taylor, W. F. (Editor)

    1979-01-01

    Various aspects of the thermal stability problem associated with the use of broadened-specification and nonpetroleum-derived turbine fuels are addressed. The state of the art is reviewed and the status of the research being conducted at various laboratories is presented. Discussions among representatives from universities, refineries, engine and airframe manufacturers, airlines, the Government, and others are presented along with conclusions and both broad and specific recommendations for future stability research and development. It is concluded that significant additional effort is required to cope with the fuel stability problems which will be associated with the potentially poorer quality fuels of the future such as broadened specification petroleum fuels or fuels produced from synthetic sources.

  7. Fuel cell water transport

    DOEpatents

    Vanderborgh, Nicholas E.; Hedstrom, James C.

    1990-01-01

    The moisture content and temperature of hydrogen and oxygen gases is regulated throughout traverse of the gases in a fuel cell incorporating a solid polymer membrane. At least one of the gases traverses a first flow field adjacent the solid polymer membrane, where chemical reactions occur to generate an electrical current. A second flow field is located sequential with the first flow field and incorporates a membrane for effective water transport. A control fluid is then circulated adjacent the second membrane on the face opposite the fuel cell gas wherein moisture is either transported from the control fluid to humidify a fuel gas, e.g., hydrogen, or to the control fluid to prevent excess water buildup in the oxidizer gas, e.g., oxygen. Evaporation of water into the control gas and the control gas temperature act to control the fuel cell gas temperatures throughout the traverse of the fuel cell by the gases.

  8. Low emissions diesel fuel

    DOEpatents

    Compere, A.L.; Griffith, W.L.; Dorsey, G.F.; West, B.H.

    1998-05-05

    A method and matter of composition for controlling NO{sub x} emissions from existing diesel engines. The method is achieved by adding a small amount of material to the diesel fuel to decrease the amount of NO{sub x} produced during combustion. Specifically, small amounts, less than about 1%, of urea or a triazine compound (methylol melamines) are added to diesel fuel. Because urea and triazine compounds are generally insoluble in diesel fuel, microemulsion technology is used to suspend or dissolve the urea or triazine compound in the diesel fuel. A typical fuel formulation includes 5% t-butyl alcohol, 4.5% water, 0.5% urea or triazine compound, 9% oleic acid, and 1% ethanolamine. The subject invention provides improved emissions in heavy diesel engines without the need for major modifications.

  9. Low emissions diesel fuel

    DOEpatents

    Compere, Alicia L.; Griffith, William L.; Dorsey, George F.; West, Brian H.

    1998-01-01

    A method and matter of composition for controlling NO.sub.x emissions from existing diesel engines. The method is achieved by adding a small amount of material to the diesel fuel to decrease the amount of NO.sub.x produced during combustion. Specifically, small amounts, less than about 1%, of urea or a triazine compound (methylol melamines) are added to diesel fuel. Because urea and triazine compounds are generally insoluble in diesel fuel, microemulsion technology is used to suspend or dissolve the urea or triazine compound in the diesel fuel. A typical fuel formulation includes 5% t-butyl alcohol, 4.5% water, 0.5% urea or triazine compound, 9% oleic acid, and 1% ethanolamine. The subject invention provides improved emissions in heavy diesel engines without the need for major modifications.

  10. Smog control fuel additives

    SciTech Connect

    Lundby, W.

    1993-06-29

    A method is described of controlling, reducing or eliminating, ozone and related smog resulting from photochemical reactions between ozone and automotive or industrial gases comprising the addition of iodine or compounds of iodine to hydrocarbon-base fuels prior to or during combustion in an amount of about 1 part iodine per 240 to 10,000,000 parts fuel, by weight, to be accomplished by: (a) the addition of these inhibitors during or after the refining or manufacturing process of liquid fuels; (b) the production of these inhibitors for addition into fuel tanks, such as automotive or industrial tanks; or (c) the addition of these inhibitors into combustion chambers of equipment utilizing solid fuels for the purpose of reducing ozone.

  11. Alternative fuel transit buses

    SciTech Connect

    Motta, R.; Norton, P.; Kelly, K.

    1996-10-01

    The National Renewable Energy Laboratory (NREL) is a U.S. Department of Energy (DOE) national laboratory; this project was funded by DOE. One of NREL`s missions is to objectively evaluate the performance, emissions, and operating costs of alternative fuel vehicles so fleet managers can make informed decisions when purchasing them. Alternative fuels have made greater inroads into the transit bus market than into any other. Each year, the American Public Transit Association (APTA) surveys its members on their inventory and buying plans. The latest APTA data show that about 4% of the 50,000 transit buses in its survey run on an alternative fuel. Furthermore, 1 in 5 of the new transit buses that members have on order are alternative fuel buses. This program was designed to comprehensively and objectively evaluate the alternative fuels in use in the industry.

  12. Hydrogen Fuel Quality

    SciTech Connect

    Rockward, Tommy

    2012-07-16

    For the past 6 years, open discussions and/or meetings have been held and are still on-going with OEM, Hydrogen Suppliers, other test facilities from the North America Team and International collaborators regarding experimental results, fuel clean-up cost, modeling, and analytical techniques to help determine levels of constituents for the development of an international standard for hydrogen fuel quality (ISO TC197 WG-12). Significant progress has been made. The process for the fuel standard is entering final stages as a result of the technical accomplishments. The objectives are to: (1) Determine the allowable levels of hydrogen fuel contaminants in support of the development of science-based international standards for hydrogen fuel quality (ISO TC197 WG-12); and (2) Validate the ASTM test method for determining low levels of non-hydrogen constituents.

  13. Jet aircraft hydrocarbon fuels technology

    NASA Technical Reports Server (NTRS)

    Longwell, J. P. (Editor)

    1978-01-01

    A broad specification, referee fuel was proposed for research and development. This fuel has a lower, closely specified hydrogen content and higher final boiling point and freezing point than ASTM Jet A. The workshop recommended various priority items for fuel research and development. Key items include prediction of tradeoffs among fuel refining, distribution, and aircraft operating costs; combustor liner temperature and emissions studies; and practical simulator investigations of the effect of high freezing point and low thermal stability fuels on aircraft fuel systems.

  14. Fuel properties of cottonseed oil

    SciTech Connect

    Karaosmanoglu, F.; Tueter, M.; Goellue, E.; Yanmaz, S.; Altintig, E.

    1999-11-01

    The use of vegetable oils as fuel alternatives has an exceptional importance in the field of research. In this study, evaluation possibilities of cottonseed oil have been investigated as an alternative candidate for diesel fuel and fuel oil. The fuel property tests were performed according to standard analysis methods for oil and fuel. An overall evaluation of the results indicates that cottonseed oil can be proposed as a possible green substitute for fuel.

  15. Rejuvenation of automotive fuel cells

    SciTech Connect

    Kim, Yu Seung; Langlois, David A.

    2016-08-23

    A process for rejuvenating fuel cells has been demonstrated to improve the performance of polymer exchange membrane fuel cells with platinum/ionomer electrodes. The process involves dehydrating a fuel cell and exposing at least the cathode of the fuel cell to dry gas (nitrogen, for example) at a temperature higher than the operating temperature of the fuel cell. The process may be used to prolong the operating lifetime of an automotive fuel cell.

  16. Advanced fuel chemistry for advanced engines.

    SciTech Connect

    Taatjes, Craig A.; Jusinski, Leonard E.; Zador, Judit; Fernandes, Ravi X.; Miller, James A.

    2009-09-01

    Autoignition chemistry is central to predictive modeling of many advanced engine designs that combine high efficiency and low inherent pollutant emissions. This chemistry, and especially its pressure dependence, is poorly known for fuels derived from heavy petroleum and for biofuels, both of which are becoming increasingly prominent in the nation's fuel stream. We have investigated the pressure dependence of key ignition reactions for a series of molecules representative of non-traditional and alternative fuels. These investigations combined experimental characterization of hydroxyl radical production in well-controlled photolytically initiated oxidation and a hybrid modeling strategy that linked detailed quantum chemistry and computational kinetics of critical reactions with rate-equation models of the global chemical system. Comprehensive mechanisms for autoignition generally ignore the pressure dependence of branching fractions in the important alkyl + O{sub 2} reaction systems; however we have demonstrated that pressure-dependent 'formally direct' pathways persist at in-cylinder pressures.

  17. Science based integrated approach to advanced nuclear fuel development - vision, approach, and overview

    SciTech Connect

    Unal, Cetin; Pasamehmetoglu, Kemal; Carmack, Jon

    2010-01-01

    Advancing the performance of Light Water Reactors, Advanced Nuclear Fuel Cycles, and Advanced Rcactors, such as the Next Generation Nuclear Power Plants, requires enhancing our fundamental understanding of fuel and materials behavior under irradiation. The capability to accurately model the nuclear fuel systems is critical. In order to understand specific aspects of the nuclear fuel, fully coupled fuel simulation codes are required to achieve licensing of specific nuclear fuel designs for operation. The backbone of these codes, models, and simulations is a fundamental understanding and predictive capability for simulating the phase and microstructural behavior of the nuclear fuel system materials and matrices. The purpose of this paper is to identify the modeling and simulation approach in order to deliver predictive tools for advanced fuels development. The coordination between experimental nuclear fuel design, development technical experts, and computational fuel modeling and simulation technical experts is a critical aspect of the approach and naturally leads to an integrated, goal-oriented science-based R & D approach and strengthens both the experimental and computational efforts. The Advanced Fuels Campaign (AFC) and Nuclear Energy Advanced Modeling and Simulation (NEAMS) Fuels Integrated Performance and Safety Code (IPSC) are working together to determine experimental data and modeling needs. The primary objective of the NEAMS fuels IPSC project is to deliver a coupled, three-dimensional, predictive computational platform for modeling the fabrication and both normal and abnormal operation of nuclear fuel pins and assemblies, applicable to both existing and future reactor fuel designs. The science based program is pursuing the development of an integrated multi-scale and multi-physics modeling and simulation platform for nuclear fuels. This overview paper discusses the vision, goals and approaches how to develop and implement the new approach.

  18. Low contaminant formic acid fuel for direct liquid fuel cell

    DOEpatents

    Masel, Richard I.; Zhu, Yimin; Kahn, Zakia; Man, Malcolm

    2009-11-17

    A low contaminant formic acid fuel is especially suited toward use in a direct organic liquid fuel cell. A fuel of the invention provides high power output that is maintained for a substantial time and the fuel is substantially non-flammable. Specific contaminants and contaminant levels have been identified as being deleterious to the performance of a formic acid fuel in a fuel cell, and embodiments of the invention provide low contaminant fuels that have improved performance compared to known commercial bulk grade and commercial purified grade formic acid fuels. Preferred embodiment fuels (and fuel cells containing such fuels) including low levels of a combination of key contaminants, including acetic acid, methyl formate, and methanol.

  19. Alternate-Fueled Flight: Halophytes, Algae, Bio-, and Synthetic Fuels

    NASA Technical Reports Server (NTRS)

    Hendricks, R. C.

    2012-01-01

    Synthetic and biomass fueling are now considered to be near-term aviation alternate fueling. The major impediment is a secure sustainable supply of these fuels at reasonable cost. However, biomass fueling raises major concerns related to uses of common food crops and grasses (some also called "weeds") for processing into aviation fuels. These issues are addressed, and then halophytes and algae are shown to be better suited as sources of aerospace fuels and transportation fueling in general. Some of the history related to alternate fuels use is provided as a guideline for current and planned alternate fuels testing (ground and flight) with emphasis on biofuel blends. It is also noted that lessons learned from terrestrial fueling are applicable to space missions. These materials represent an update (to 2009) and additions to the Workshop on Alternate Fueling Sustainable Supply and Halophyte Summit at Twinsburg, Ohio, October 17 to 18, 2007.

  20. Alternate-Fueled Flight: Halophytes, Algae, Bio-, and Synthetic Fuels

    NASA Technical Reports Server (NTRS)

    Hendricks, R. C.

    2007-01-01

    Synthetic and biomass fueling are now considered to be near-term aviation alternate fueling. The major impediment is a secure sustainable supply of these fuels at reasonable cost. However, biomass fueling raises major concerns related to uses of common food crops and grasses (some also called "weeds") for processing into aviation fuels. These issues are addressed, and then halophytes and algae are shown to be better suited as sources of aerospace fuels and transportation fueling in general. Some of the history related to alternate fuels use is provided as a guideline for current and planned alternate fuels testing (ground and flight) with emphasis on biofuel blends. It is also noted that lessons learned from terrestrial fueling are applicable to space missions. These materials represent an update and additions to the Workshop on Alternate Fueling Sustainable Supply and Halophyte Summit at Twinsburg, OH, Oct. 17 to 18, 2007 (ref. 1).