Sample records for fuels modeling transition

  1. Lessons Learned from Alternative Transportation Fuels: Modeling Transition Dynamics

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

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative1 First Use of Energy for All Purposes (Fuel and Nonfuel), 2002; Level: National5Sales for4,645U.S. DOEThe Bonneville PowerCherries 82981-1cnHigh SchoolIn12electron 9 5 -ofLearningLensless4

  2. Alternative Fuel Transit Buses

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

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative1 First Use of Energy for All Purposes (Fuel and Nonfuel), 2002; Level: National5Sales for4,645U.S. DOE Office511041cloth DocumentationProducts (VAP) VAP7-0973ManagedStrategic|AljazeeraO S o'ware a ndManterEPAct35th

  3. Managing the transition toward self-sustaining alternative fuel vehicle markets : policy analysis using a dynamic behavioral spatial model

    E-Print Network [OSTI]

    Supple, Derek R. (Derek Richard)

    2007-01-01T23:59:59.000Z

    Designing public policy or industry strategy to bolster the transition to alternative fuel vehicles (AFVs) is a formidable challenge as demonstrated by historical failed attempts. The transition to new fuels occurs within ...

  4. Fuel Cell Transit Bus Coordination and Evaluation Plan California...

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

    Bus Coordination and Evaluation Plan California Fuel Cell Transit Evaluation Team Fuel Cell Transit Bus Coordination and Evaluation Plan California Fuel Cell Transit Evaluation...

  5. Connecticut Transit (CTTRANSIT) Fuel Cell Transit Bus: Preliminary Evaluation Results

    SciTech Connect (OSTI)

    Chandler, K.; Eudy, L.

    2008-10-01T23:59:59.000Z

    This report provides preliminary results from a National Renewable Energy Laboratory evaluation of a protoptye fuel cell transit bus operating at Connecticut Transit in Hartford. Included are descriptions of the planned fuel cell bus demonstration and equipment; early results and agency experience are also provided.

  6. Checklist for transition to new highway fuel(s).

    SciTech Connect (OSTI)

    Risch, C.; Santini, D.J. (Energy Systems)

    2011-12-15T23:59:59.000Z

    Transportation is vital to the U.S. economy and society. As such, U.S. Presidents have repeatedly stated that the nation needs to reduce dependence on petroleum, especially for the highway transportation sector. Throughout history, highway transportation fuel transitions have been completed successfully both in United States and abroad. Other attempts have failed, as described in Appendix A: Historical Highway Fuel Transitions. Planning for a transition is critical because the changes can affect our nation's ability to compete in the world market. A transition will take many years to complete. While it is tempting to make quick decisions about the new fuel(s) of choice, it is preferable and necessary to analyze all the pertinent criteria to ensure that correct decisions are made. Doing so will reduce the number of changes in highway fuel(s). Obviously, changes may become necessary because of occurrences such as significant technology breakthroughs or major world events. With any and all of the possible transitions to new fuel(s), the total replacement of gasoline and diesel fuels is not expected. These conventional fuels are envisioned to coexist with the new fuel(s) for decades, while the revised fuel and vehicle infrastructures are implemented. The transition process must analyze the needs of the primary 'players,' which consist of the customers, the government, the fuel industry, and the automotive industry. To maximize the probability of future successes, the prime considerations of these groups must be addressed. Section 2 presents a succinct outline of the Checklist. Section 3 provides a brief discussion about the groupings on the Checklist.

  7. Alameda-Contra Costa Transit District (AC Transit) Fuel Cell Transit Buses: Preliminary Evaluation Results

    SciTech Connect (OSTI)

    Chandler, K.; Eudy, L.

    2007-03-01T23:59:59.000Z

    This report provides an evaluation of three prototype fuel cell-powered transit buses operating at AC Transit in Oakland, California, and six baseline diesel buses similar in design to the fuel cell buses.

  8. Fuel Cells Technology Transit | Open Energy Information

    Open Energy Info (EERE)

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Home Page onYou are now leaving Energy.gov You are now leaving Energy.gov You are being directedAnnualPropertyd8c-a9ae-f8521cbb8489InformationFrenchtown, New Jersey:Transit Jump to: navigation,

  9. alternative fuel transit: Topics by E-print Network

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

    Transportation Fuels? Alternative Fuels, the Smart Choice: Alternative fuels - biodiesel, electricity, ethanol (E85), natural gas 4 UCSF BART Strike Transit Alternatives...

  10. Dynamic Analysis of Fuel Cycle Transitioning

    SciTech Connect (OSTI)

    Brent Dixon; Steve Piet; David Shropshire; Gretchen Matthern

    2009-09-01T23:59:59.000Z

    This paper examines the time-dependent dynamics of transitioning from a once-through fuel cycle to a closed fuel cycle. The once-through system involves only Light Water Reactors (LWRs) operating on uranium oxide fuel UOX), while the closed cycle includes both LWRs and fast spectrum reactors (FRs) in either a single-tier system or two-tier fuel system. The single-tier system includes full transuranic recycle in FRs while the two-tier system adds one pass of mixed oxide uranium-plutonium (MOX U-Pu) fuel in the LWR. While the analysis primarily focuses on burner fast reactors, transuranic conversion ratios up to 1.0 are assessed and many of the findings apply to any fuel cycle transitioning from a thermal once-through system to a synergistic thermal-fast recycle system. These findings include uranium requirements for a range of nuclear electricity growth rates, the importance of back end fuel cycle facility timing and magnitude, the impact of employing a range of fast reactor conversion ratios, system sensitivity to used fuel cooling time prior to recycle, impacts on a range of waste management indicators, and projected electricity cost ranges for once-through, single-tier and two-tier systems. The study confirmed that significant waste management benefits can be realized as soon as recycling is initiated, but natural uranium savings are minimal in this century. The use of MOX in LWRs decouples the development of recycle facilities from fast reactor fielding, but also significantly delays and limits fast reactor deployment. In all cases, fast reactor deployment was significantly below than predicted by static equilibrium analyses.

  11. SunLine Transit Agency Fuel Cell Transit Bus: Fifth Evaluation...

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

    1 August 2009 SunLine Transit Agency Fuel Cell Transit Bus: Fifth Evaluation Report Leslie Eudy, National Renewable Energy Laboratory Kevin Chandler, Battelle Link to Appendices...

  12. SunLine Transit Agency Fuel Cell Transit Bus: Fourth Evaluation...

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

    1 January 2009 SunLine Transit Agency Fuel Cell Transit Bus: Fourth Evaluation Report Kevin Chandler, Battelle Leslie Eudy, National Renewable Energy Laboratory Link to Appendices...

  13. A smooth transition to hydrogen transportation fuel

    SciTech Connect (OSTI)

    Berry, G.D.; Smith, J.R.; Schock, R.N.

    1995-04-14T23:59:59.000Z

    The goal of this work is to examine viable near-term infrastructure options for a transition to hydrogen fueled vehicles and to suggest profitable directions for technology development. The authors have focused in particular on the contrasting options of decentralized production using the existing energy distribution network, and centralized production of hydrogen with a large-scale infrastructure. Delivered costs have been estimated using best available industry cost and deliberately conservative economic assumptions. The sensitivities of these costs have then been examined for three small-scale scenarios: (1) electrolysis at the home for one car, and production at the small station scale (300 cars/day), (2) conventional alkaline electrolysis and (3) steam reforming of natural gas. All scenarios assume fueling a 300 mile range vehicle with 3.75 kg. They conclude that a transition appears plausible, using existing energy distribution systems, with home electrolysis providing fuel costing 7.5 to 10.5{cents}/mile, station electrolysis 4.7 to 7.1{cents}/mile, and steam reforming 3.7 to 4.7{cents}/mile. The average car today costs about 6{cents}/mile to fuel. Furthermore, analysis of liquid hydrogen delivered locally by truck from central processing plants can also be competitive at costs as low as 4{cents}/mile. These delivered costs are equal to $30 to $70 per GJ, LHV. Preliminary analysis indicates that electricity transmission costs favor this method of distributing energy, until very large (10 GW) hydrogen pipelines are installed. This indicates that significant hydrogen pipeline distribution will be established only when significant markets have developed.

  14. DYNAMIC MODELING FUEL PROCESSORS

    E-Print Network [OSTI]

    Mease, Kenneth D.

    turbine module (compressor and turbine sub-modules) Catalytic oxidizer Combustor module Heat exchanger, PEM, Gas Turbine General Model Assumptions · 1D process flow · Well-stirred within nodal volume · Slow reactants #12;Steam Reformation ­ Occurs in Reformer and Fuel Cells Methane reformation reaction Water Gas

  15. VISION: Verifiable Fuel Cycle Simulation Model

    SciTech Connect (OSTI)

    Jacob J. Jacobson; Abdellatif M. Yacout; Gretchen E. Matthern; Steven J. Piet; David E. Shropshire

    2009-04-01T23:59:59.000Z

    The nuclear fuel cycle is a very complex system that includes considerable dynamic complexity as well as detail complexity. In the nuclear power realm, there are experts and considerable research and development in nuclear fuel development, separations technology, reactor physics and waste management. What is lacking is an overall understanding of the entire nuclear fuel cycle and how the deployment of new fuel cycle technologies affects the overall performance of the fuel cycle. The Advanced Fuel Cycle Initiative’s systems analysis group is developing a dynamic simulation model, VISION, to capture the relationships, timing and delays in and among the fuel cycle components to help develop an understanding of how the overall fuel cycle works and can transition as technologies are changed. This paper is an overview of the philosophy and development strategy behind VISION. The paper includes some descriptions of the model and some examples of how to use VISION.

  16. Connecticut Transit (CTTRANSIT) Fuel Cell Transit Bus: Preliminary

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

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Home Page on Google Bookmark EERE: Alternative Fuels DataDepartment of Energy Your Density Isn't Your Destiny: Theof"Wave the WhiteNational|ofSeptemberConfrontingFY 2011

  17. Alternative Fuels Data Center: Mass Transit

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

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative1 First Use of Energy for All Purposes (Fuel and Nonfuel), 2002; Level: National5Sales for4,645 3,625govInstrumentstdmadapInactiveVisiting the TWP TWP RelatedCellulaseFuels and Vehicles Maryland

  18. Connecticut Transit (CTTRANSIT) Fuel Cell Transit Bus: Second Evaluation

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

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative1 First Use of Energy for All Purposes (Fuel and Nonfuel), 2002; Level: National5Sales for4,645 3,625 1,006 492 742Energy China U.S. DepartmentEnergy This partAs theFebruary09 FY 2009 ($ConnecticutSummary

  19. Connecticut Transit (CTTRANSIT) Fuel Cell Transit Bus: Third Evaluation

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

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative1 First Use of Energy for All Purposes (Fuel and Nonfuel), 2002; Level: National5Sales for4,645 3,625 1,006 492 742Energy China U.S. DepartmentEnergy This partAs theFebruary09 FY 2009

  20. Fuel Cells in Transit Buses Transit buses are widely viewed as one of the best strategies for commercializing fuel cells for

    E-Print Network [OSTI]

    for commercializing fuel cells for vehicles and transitioning to a hydrogen economy. Many advantages have beenFuel Cells in Transit Buses Summary Transit buses are widely viewed as one of the best strategies identified regarding the use of transit buses as fuel cell platforms. For example: · Transit buses have well

  1. Alameda-Contra Costa Transit District (AC Transit) Fuel Cell Transit Buses: Third Evaluation Report and Appendices

    SciTech Connect (OSTI)

    Chandler, K.; Eudy, L.

    2008-07-01T23:59:59.000Z

    This report describes operations at Alameda-Contra Costa Transit district for three protoype fuel cell buses and six diesel buses operating from the same location.

  2. Alternative Fuels Data Center: Active Transit

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

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative1 First Use of Energy for All Purposes (Fuel and Nonfuel), 2002; Level: National5Sales for4,645 3,625govInstrumentstdmadapInactiveVisiting the TWP TWP RelatedCellulase C.Tier 2 andIndependence andStateLocate

  3. Alternative Fuel Transit Buses: DART's (Dallas Area Rapid Transit) LNG Bus Fleet Final Results

    SciTech Connect (OSTI)

    Chandler, K. [Battelle (US); Norton, P. [National Renewable Energy Lab., Golden, CO (US); Clark, N.

    2000-11-07T23:59:59.000Z

    In 1998, Dallas Area Rapid Transit, a public transit agency in Dallas, Texas, began operating a large fleet of heavy-duty buses powered by liquefied natural gas. As part of a $16 million commitment to alternative fuels, DART operates 139 LNG buses serviced by two new LNG fueling stations.

  4. BC Transit Fuel Cell Bus Project: Evaluation Results Report

    SciTech Connect (OSTI)

    Eudy, L.; Post, M.

    2014-02-01T23:59:59.000Z

    This report evaluates a fuel cell electric bus demonstration led by British Columbia Transit (BC Transit) in Whistler, Canada. BC Transit is collaborating with the California Air Resources Board and the U.S. Department of Energy's National Renewable Energy Laboratory to evaluate the buses in revenue service. This evaluation report covers two years of revenue service data on the buses from April 2011 through March 2013.

  5. Fuel Cell Transit Buses: ThunderPower Bus Evaluation at SunLine...

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

    Fuel Cell Transit Buses: ThunderPower Bus Evaluation at SunLine Transit Agency Fuel Cell Transit Buses: ThunderPower Bus Evaluation at SunLine Transit Agency Report details the...

  6. SunLine Transit Agency Fuel Cell Transit Bus: Fifth Evaluation...

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

    operations at SunLine Transit Agency for a prototype fuel cell bus and five compressed natural gas (CNG) buses. This is the fifth evaluation report for this site, and it...

  7. Tool and Calculator (Transit, Fuel) | Open Energy Information

    Open Energy Info (EERE)

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Home Page onYou are now leaving Energy.gov You are now leaving Energy.gov You are beingZealand Jump to:Ezfeedflag JumpID-f <MaintainedInformationThePty LtdOpenHabitatand Calculator (Transit,

  8. BC Transit Fuel Cell Bus Project Evaluation Results: Second Report

    SciTech Connect (OSTI)

    Eudy, L.; Post, M.

    2014-09-01T23:59:59.000Z

    Second report evaluating a fuel cell electric bus (FCEB) demonstration led by British Columbia Transit (BC Transit) in Whistler, Canada. BC Transit is collaborating with the California Air Resources Board and the U.S. Department of Energy's National Renewable Energy Laboratory to evaluate the buses in revenue service. NREL published its first report on the demonstration in February 2014. This report is an update to the previous report; it covers 3 full years of revenue service data on the buses from April 2011 through March 2014 and focuses on the final experiences and lessons learned.

  9. Modeling the Nuclear Fuel Cycle

    SciTech Connect (OSTI)

    Jacob J. Jacobson; A. M. Yacout; G. E. Matthern; S. J. Piet; A. Moisseytsev

    2005-07-01T23:59:59.000Z

    The Advanced Fuel Cycle Initiative is developing a system dynamics model as part of their broad systems analysis of future nuclear energy in the United States. The model will be used to analyze and compare various proposed technology deployment scenarios. The model will also give a better understanding of the linkages between the various components of the nuclear fuel cycle that includes uranium resources, reactor number and mix, nuclear fuel type and waste management. Each of these components is tightly connected to the nuclear fuel cycle but usually analyzed in isolation of the other parts. This model will attempt to bridge these components into a single model for analysis. This work is part of a multi-national laboratory effort between Argonne National Laboratory, Idaho National Laboratory and United States Department of Energy. This paper summarizes the basics of the system dynamics model and looks at some results from the model.

  10. National Fuel Cell Bus Program: Accelerated Testing Evaluation Report and Appendices, Alameda-Contra Costa Transit District (AC Transit)

    SciTech Connect (OSTI)

    Chandler, K.; Eudy, L.

    2009-01-01T23:59:59.000Z

    This is an evaluation of hydrogen fuel cell transit buses operating at AC Transit in revenue service since March 20, 2006 compared to similar diesel buses operating from the same depot. This evaluation report includes results from November 2007 through October 2008. Evaluation results include implementation experience, fueling station operation, fuel cell bus operations at Golden Gate Transit, and evaluation results at AC Transit (bus usage, availability, fuel economy, maintenance costs, and roadcalls).

  11. Fuel Cell Buses in U.S. Transit Fleets: Current Status 2009

    SciTech Connect (OSTI)

    Eudy, L.; Chandler, K.; Gikakis, C.

    2009-10-01T23:59:59.000Z

    This report documents progress in meeting the technological challenges of fuel cell propulsion for transportation based on current fuel cell transit bus demonstrations and plans for more fuel cell transit buses and hydrogen infrastructure.

  12. Ising model: secondary phase transition

    E-Print Network [OSTI]

    You-gang Feng

    2012-04-09T23:59:59.000Z

    Lttice-spin phonons are considered, which make the heat capacity at the critical temperature satisfy experimental observations better. There is a BEC phase transition in an Ising model attributable to the lattice-spin phonons. We proved that the spin-wave theory only is available after BEC transition, and the magnons have the same characteristics as the lattice-spin phonons', resulting from quantum effect. Energy-level overlap effect at ultralow temperature is found. A prediction of BEC phase transition in a crystal is put forward as our theory generalization.

  13. Connecticut Transit (CTTRANSIT) Fuel Cell Transit Bus: Third Evaluation Report and Appendices

    SciTech Connect (OSTI)

    Chandler, K.; Eudy, L.

    2010-01-01T23:59:59.000Z

    This report describes operations at Connecticut Transit (CTTRANSIT) in Hartford for one prototype fuel cell bus and three new diesel buses operating from the same location. The prototype fuel cell bus was manufactured by Van Hool and ISE Corp. and features an electric hybrid drive system with a UTC Power PureMotion 120 Fuel Cell Power System and ZEBRA batteries for energy storage. The fuel cell bus started operation in April 2007, and evaluation results through October 2009 are provided in this report.

  14. Speeding the transition: Designing a fuel-cell hypercar

    SciTech Connect (OSTI)

    Williams, B.D.; Moore, T.C.; Lovins, A.B. [Rocky Mountain Inst., Snowmass, CO (United States). Hypercar Center

    1997-12-31T23:59:59.000Z

    A rapid transformation now underway in automotive technology could accelerate the transition to transportation powered by fuel cells. Ultralight, advanced-composite, low-drag, hybrid-electric hypercars--using combustion engines--could be three- to fourfold more efficient and one or two orders of magnitude cleaner than today`s cars, yet equally safe, sporty, desirable, and (probably) affordable. Further, important manufacturing advantages--including low tooling and equipment costs, greater mechanical simplicity, autobody parts consolidation, shorter product cycles, and reduced assembly effort and space--permit a free-market commercialization strategy. This paper discusses a conceptual hypercar powered by a proton-exchange-membrane fuel cell (PEMFC). It outlines the implications of platform physics and component selection for the vehicle`s mass budget and performance. The high fuel-to-traction conversion efficiency of the hypercar platform could help automakers overcome the Achilles` heel of hydrogen-powered vehicles: onboard storage. Moreover, because hypercars would require significantly less tractive power, and even less fuel-cell power, they could adopt fuel cells earlier, before fuel cells` specific cost, mass, and volume have fully matured. In the meantime, commercialization in buildings can help prepare fuel cells for hypercars. The promising performance of hydrogen-fueled PEMFC hypercars suggests important opportunities in infrastructure development for direct-hydrogen vehicles.

  15. Fuel Cell Buses in U.S. Transit Fleets: Current Status 2012

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

    Fuel Cell Buses in U.S. Transit Fleets: Current Status 2012 Leslie Eudy National Renewable Energy Laboratory Kevin Chandler Battelle Christina Gikakis Federal Transit...

  16. Fuel Cell Buses in U.S. Transit Fleets: Current Status 2008

    SciTech Connect (OSTI)

    Eudy, L.; Chandler, K.; Gikakis, C.

    2008-12-01T23:59:59.000Z

    This report provides results from fuel cell bus evaluations at Alameda-Contra Costa Transit District, SunLine Transit Agency, and Santa Clara Valley Transportation Authority.

  17. Fuel Cell Buses in U.S. Transit Fleets: Current Status 2008

    Broader source: Energy.gov [DOE]

    This report provides results from fuel cell bus evaluations at Alameda-Contra Costa Transit District, SunLine Transit Agency, and Santa Clara Valley Transportation Authority.

  18. Crossover transition in bag-like models

    E-Print Network [OSTI]

    Ferroni, Lorenzo

    2009-01-01T23:59:59.000Z

    DE-AC02-05CH11231 Crossover transition in bag-like models L.We show that a crossover transition qualitatively similar toI. INTRODUCTION The phase transition of strongly interacting

  19. SunLine Transit Agency Fuel Cell Transit Bus: Fifth Evaluation Report-- Appendices

    Broader source: Energy.gov [DOE]

    This report describes operations at SunLine Transit Agency for a prototype fuel cell bus and five compressed natural gas (CNG) buses. This is the fifth evaluation report for this site, and it describes results and experiences from October 2008 through June 2009. These results are an addition to those provided in the previous four evaluation reports.

  20. Connecticut Transit (CTTRANSIT) Fuel Cell Transit Bus: Second Evaluation Report and Appendices

    SciTech Connect (OSTI)

    Chandler, K.; Eudy, L.

    2009-05-01T23:59:59.000Z

    This report describes operations at Connecticut Transit (CTTRANSIT) in Hartford for one prototype fuel cell bus and three new diesel buses operating from the same location. The evaluation period in this report (January 2008 through February 2009) has been chosen to coincide with a UTC Power propulsion system changeout that occurred on January 15, 2008.

  1. SunLine Transit Agency Fuel Cell Transit Bus: Fifth Evaluation Report (Report and Appendices)

    SciTech Connect (OSTI)

    Eudy, L.; Chandler, K.

    2009-08-01T23:59:59.000Z

    This report describes operations at SunLine Transit Agency for a prototype fuel cell bus and five compressed natural gas (CNG) buses. This is the fifth evaluation report for this site, and it describes results and experiences from October 2008 through June 2009. These results are an addition to those provided in the previous four evaluation reports.

  2. SunLine Transit Agency Fuel Cell Transit Bus: Fourth Evaluation Report (Report and Appendices)

    SciTech Connect (OSTI)

    Chandler, K.; Eudy, L.

    2009-01-01T23:59:59.000Z

    This report describes operations at SunLine Transit Agency for a prototype fuel cell bus and five new compressed natural gas (CNG) buses. This is the fourth evaluation report for this site, and it describes results and experiences from April 2008 through October 2008. These results are an addition to those provided in the previous three evaluation reports.

  3. Fuel Cell Buses in U.S. Transit Fleets: Summary of Experiences...

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

    report reviews past and present fuel cell bus technology development and implementation in the United States. 41967.pdf More Documents & Publications Hydrogen and Fuel Cell Transit...

  4. Fuel Cell Transit Buses: ThunderPower Bus Evaluation at SunLine...

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

    Agency Transit Buses Hydrogen, Fuel Cells & Infrastructure Technologies Program Fuel Cell A Strong Energy Portfolio for a Strong America Energy effi ciency and clean, renewable...

  5. Fuel Cell Buses in U.S. Transit Fleets: Current Status 2012 ...

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

    Fuel Cell Buses in U.S. Transit Fleets: Current Status 2012 Fuel Cell Buses in U.S. Transit Fleets: Current Status 2012 This report is the sixth in an annual series of reports that...

  6. Alameda-Contra Costa Transit District (AC Transit) Fuel Cell Transit Buses:

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

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Home Page on Google Bookmark EERE: Alternative Fuels DataDepartment of Energy Your Density Isn't Your Destiny: The Future of1Albuquerque, NM - Building Americaof42.2Air-SourceAustin, TThird

  7. Alameda-Contra Costa Transit District (AC Transit) Fuel Cell Transit Buses:

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

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Home Page on Google Bookmark EERE: Alternative Fuels DataDepartment of Energy Your Density Isn't Your Destiny: The Future of1Albuquerque, NM - Building Americaof42.2Air-SourceAustin,

  8. Phase Transition in Tensor Models

    E-Print Network [OSTI]

    Delepouve, Thibault

    2015-01-01T23:59:59.000Z

    Generalizing matrix models, tensor models generate dynamical triangulations in any dimension and support a $1/N$ expansion. Using the intermediate field representation we explicitly rewrite a quartic tensor model as a field theory for a fluctuation field around a vacuum state corresponding to the resummation of the entire leading order in $1/N$ (a resummation of the melonic family). We then prove that the critical regime in which the continuum limit in the sense of dynamical triangulations is reached is precisely a phase transition in the field theory sense for the fluctuation field.

  9. Assessment of transition fuel cycle performance with and without a modified-open fuel cycle

    SciTech Connect (OSTI)

    Feng, B.; Kim, T. K.; Taiwo, T. A. [Argonne National Laboratory, 9700 S. Cass Avenue, Argonne, IL 60439 (United States)

    2012-07-01T23:59:59.000Z

    The impacts of a modified-open fuel cycle (MOC) option as a transition step from the current once-through cycle (OTC) to a full-recycle fuel cycle (FRC) were assessed using the nuclear systems analysis code DANESS. The MOC of interest for this study was mono-recycling of plutonium in light water reactors (LWR-MOX). Two fuel cycle scenarios were evaluated with and without the MOC option: a 2-stage scenario with a direct path from the current fleet to the final FRC, and a 3-stage scenario with the MOC option as a transition step. The FRC reactor (fast reactor) was assumed to deploy in 2050 for both scenarios, and the MOC reactor in the 3-stage scenario was assumed to deploy in 2025. The last LWRs (using either UOX or MOX fuels) come online in 2050 and are decommissioned by 2110. Thus, the FRC is achieved after 2110. The reprocessing facilities were assumed to be available 2 years prior to the deployment of the MOC and FRC reactors with maximum reprocessing capacities of 2000 tHM/yr and 500 tHM/t for LWR-UOX and LWR-MOX used nuclear fuels (UNFs), respectively. Under a 1% nuclear energy demand growth assumption, both scenarios were able to sustain a full transition to the FRC without delay. For the 3-stage scenario, the share of LWR-MOX reactors reaches a peak of 15% of installed capacity, which resulted in 10% lower cumulative uranium consumption and SWU requirements compared to the 2-stage scenario during the transition period. The peak UNF storage requirement decreases by 50% in the 3-stage scenario, largely due to the earlier deployment of the reprocessing plants to support the MOC fuel cycle. (authors)

  10. National Fuel Cell Bus Program: Accelerated Testing Evaluation Report #2, Alameda-Contra Costa Transit District (AC Transit) and Appendices

    SciTech Connect (OSTI)

    Eudy, L.; Chandler, K.

    2010-06-01T23:59:59.000Z

    This is an evaluation of hydrogen fuel cell transit buses operating at AC Transit in revenue service since March 20, 2006, comparing similar diesel buses operating from the same depot. It covers November 2007 through February 2010. Results include implementation experience, fueling station operation, evaluation results at AC Transit (bus usage, availability, fuel economy, maintenance costs, and road calls), and a summary of achievements and challenges encountered during the demonstration.

  11. Alameda-Contra Costa Transit District (AC Transit) Fuel Cell Transit Buses:

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

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative1 First Use of Energy for All Purposes (Fuel and Nonfuel), 2002; Level: National5Sales for4,645 3,625 1,006 492 742 33Frequently20,000 RussianBy:Whether you're a16-17, 201529,Vulnerabilities

  12. Alameda-Contra Costa Transit District (AC Transit) Fuel Cell Transit Buses: Preliminary Evaluation Results

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

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative1 First Use of Energy for All Purposes (Fuel and Nonfuel), 2002; Level: National5Sales for4,645 3,625 1,006 492 742Energy China 2015ofDepartmentDepartment of2Partners in theLoraDepartment ofTheThird

  13. Santa Clara Valley Transportation Authority and San Mateo County Transit District; Fuel Cell Transit Buses: Preliminary Evaluation Results

    SciTech Connect (OSTI)

    Eudy, L.; Chandler, K.

    2006-03-01T23:59:59.000Z

    Report provides preliminary results from an evaluation of prototype fuel cell transit buses operating at Santa Clara Valley Transportation Authority (VTA) in San Jose, California.

  14. Santa Clara Valley Transportation Authority and San Mateo County Transit District -- Fuel Cell Transit Buses: Evaluation Results

    SciTech Connect (OSTI)

    Chandler, K.; Eudy, L.

    2006-11-01T23:59:59.000Z

    This report provides evaluation results for prototype fuel cell transit buses operating at Santa Clara Valley Transportation Authority in San Jose, California.

  15. Safety evaluation of a hydrogen fueled transit bus

    SciTech Connect (OSTI)

    Coutts, D.A.; Thomas, J.K.; Hovis, G.L.; Wu, T.T. [Westinghouse Savannah River Co., Aiken, SC (United States)

    1997-12-31T23:59:59.000Z

    Hydrogen fueled vehicle demonstration projects must satisfy management and regulator safety expectations. This is often accomplished using hazard and safety analyses. Such an analysis has been completed to evaluate the safety of the H2Fuel bus to be operated in Augusta, Georgia. The evaluation methods and criteria used reflect the Department of Energy`s graded approach for qualifying and documenting nuclear and chemical facility safety. The work focused on the storage and distribution of hydrogen as the bus motor fuel with emphases on the technical and operational aspects of using metal hydride beds to store hydrogen. The safety evaluation demonstrated that the operation of the H2Fuel bus represents a moderate risk. This is the same risk level determined for operation of conventionally powered transit buses in the United States. By the same criteria, private passenger automobile travel in the United States is considered a high risk. The evaluation also identified several design and operational modifications that resulted in improved safety, operability, and reliability. The hazard assessment methodology used in this project has widespread applicability to other innovative operations and systems, and the techniques can serve as a template for other similar projects.

  16. Spent nuclear fuel reprocessing modeling

    SciTech Connect (OSTI)

    Tretyakova, S.; Shmidt, O.; Podymova, T.; Shadrin, A.; Tkachenko, V. [Bochvar Institute, 5 Rogova str., Moscow 123098 (Russian Federation); Makeyeva, I.; Tkachenko, V.; Verbitskaya, O.; Schultz, O.; Peshkichev, I. [Russian Federal Nuclear Center - VNIITF E.I. Zababakhin, p.o.box 245, Snezhinsk, 456770 (Russian Federation)

    2013-07-01T23:59:59.000Z

    The long-term wide development of nuclear power requires new approaches towards the realization of nuclear fuel cycle, namely, closed nuclear fuel cycle (CNFC) with respect to fission materials. Plant nuclear fuel cycle (PNFC), which is in fact the reprocessing of spent nuclear fuel unloaded from the reactor and the production of new nuclear fuel (NF) at the same place together with reactor plant, can be one variant of CNFC. Developing and projecting of PNFC is a complicated high-technology innovative process that requires modern information support. One of the components of this information support is developed by the authors. This component is the programme conducting calculations for various variants of process flow sheets for reprocessing SNF and production of NF. Central in this programme is the blocks library, where the blocks contain mathematical description of separate processes and operations. The calculating programme itself has such a structure that one can configure the complex of blocks and correlations between blocks, appropriate for any given flow sheet. For the ready sequence of operations balance calculations are made of all flows, i.e. expenses, element and substance makeup, heat emission and radiation rate are determined. The programme is open and the block library can be updated. This means that more complicated and detailed models of technological processes will be added to the library basing on the results of testing processes using real equipment, in test operating mode. The development of the model for the realization of technical-economic analysis of various variants of technologic PNFC schemes and the organization of 'operator's advisor' is expected. (authors)

  17. Empirical modeling of uranium nitride fuels

    E-Print Network [OSTI]

    Brozak, Daniel Edward

    1987-01-01T23:59:59.000Z

    of this work was to develop an irradiation performance data base for nitride fuels and to provide empirical modeling capabilities for fuel swelling and fission gas release in nitride fuels. The nitride fuels data base represents the most extensive effort... to date to systematically collect, evaluate and analyze irradiation performance data for nitride fuels. The data base will be a valuable tool for all researchers in the advanced fuel modeling field in that it provides a foundation for the construction...

  18. Transition Core Properties during Conversion of the NBSR from HEU to LEU Fuel

    SciTech Connect (OSTI)

    Hanson A. L.; Diamond D.

    2013-10-31T23:59:59.000Z

    The transition of the NBSR from HEU to LEU fuel is challenging due to reactivity constraints and the need to maintain an uninterrupted science program, the mission of the NBSR. The transition cannot occur with a full change of HEU to LEU fuel elements since the excess reactivity would be large enough that the NBSR would violate the technical specification for shutdown margin. Manufacturing LEU fuel elements to represent irradiated fuel elements would be cost prohibitive since 26 one-of-a-kind fuel elements would need to be manufactured. For this report a gradual transition from the present HEU fuel to the proposed LEU fuel was studied. The gradual change approach would follow the present fuel management scheme and replace four HEU fuel elements with four LEU fuel elements each cycle. This manuscript reports the results of a series of calculations to predict the neutronic characteristics and how the neutronics will change during the transition from HEU to LEU in the NBSR.

  19. Fuel Cell Buses in U.S. Transit Fleets: Current Status 2011

    SciTech Connect (OSTI)

    Eudy, L.; Chandler, K.; Gikakis, C.

    2011-11-01T23:59:59.000Z

    This status report, fifth in a series of annual status reports from the U.S. Department of Energy's National Renewable Energy Laboratory (NREL), discusses the achievements and challenges of fuel cell propulsion for transit and summarizes the introduction of fuel cell transit buses in the United States. Progress this year includes an increase in the number of fuel cell electric buses (FCEBs), from 15 to 25, operating at eight transit agencies, as well as increased diversity of the fuel cell design options for transit buses. The report also provides an analysis of the combined results from fuel cell transit bus demonstrations evaluated by NREL with a focus on the most recent data through July 2011 including fuel cell power system reliability and durability; fuel economy; roadcall; and hydrogen fueling results. These evaluations cover 22 of the 25 FCEBs currently operating.

  20. Hydrogen Transition (HyTRANS) Model

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

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Home Page on Google Bookmark EERE: Alternative Fuels Data Center Home Page onYouTube YouTube Note: Since the.pdfBreaking of Blythe SolarContaminationCurrent Technology »Clean Coal »Transition

  1. Full-fuel-cycle modeling for alternative transportation fuels

    SciTech Connect (OSTI)

    Bell, S.R.; Gupta, M. [Univ. of Alabama, Tuscaloosa, AL (United States); Greening, L.A. [Lawrence Berkeley National Lab., CA (United States). Energy and Environment Div.

    1995-12-01T23:59:59.000Z

    Utilization of alternative fuels in the transportation sector has been identified as a potential method for mitigation of petroleum-based energy dependence and pollutant emissions from mobile sources. Traditionally, vehicle tailpipe emissions have served as sole data when evaluating environmental impact. However, considerable differences in extraction and processing requirements for alternative fuels makes evident the need to consider the complete fuel production and use cycle for each fuel scenario. The work presented here provides a case study applied to the southeastern region of the US for conventional gasoline, reformulated gasoline, natural gas, and methanol vehicle fueling. Results of the study demonstrate the significance of the nonvehicle processes, such as fuel refining, in terms of energy expenditure and emissions production. Unique to this work is the application of the MOBILE5 mobile emissions model in the full-fuel-cycle analysis. Estimates of direct and indirect greenhouse gas production are also presented and discussed using the full-cycle-analysis method.

  2. Chemical Kinetic Modeling of Advanced Transportation Fuels

    SciTech Connect (OSTI)

    PItz, W J; Westbrook, C K; Herbinet, O

    2009-01-20T23:59:59.000Z

    Development of detailed chemical kinetic models for advanced petroleum-based and nonpetroleum based fuels is a difficult challenge because of the hundreds to thousands of different components in these fuels and because some of these fuels contain components that have not been considered in the past. It is important to develop detailed chemical kinetic models for these fuels since the models can be put into engine simulation codes used for optimizing engine design for maximum efficiency and minimal pollutant emissions. For example, these chemistry-enabled engine codes can be used to optimize combustion chamber shape and fuel injection timing. They also allow insight into how the composition of advanced petroleum-based and non-petroleum based fuels affect engine performance characteristics. Additionally, chemical kinetic models can be used separately to interpret important in-cylinder experimental data and gain insight into advanced engine combustion processes such as HCCI and lean burn engines. The objectives are: (1) Develop detailed chemical kinetic reaction models for components of advanced petroleum-based and non-petroleum based fuels. These fuels models include components from vegetable-oil-derived biodiesel, oil-sand derived fuel, alcohol fuels and other advanced bio-based and alternative fuels. (2) Develop detailed chemical kinetic reaction models for mixtures of non-petroleum and petroleum-based components to represent real fuels and lead to efficient reduced combustion models needed for engine modeling codes. (3) Characterize the role of fuel composition on efficiency and pollutant emissions from practical automotive engines.

  3. Fuel Cell Power (FCPower) Model

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

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Home Page on Google Bookmark EERE: Alternative Fuels Data Center Home Page onYouTube YouTube Note: Since the.pdf Flash2006-52.pdf0.pdfDepartment of Energy's2ofFuel Cell Financing forEnergy

  4. Simulations of the Fuel Economy and Emissions of Hybrid Transit Buses over Planned Local Routes

    SciTech Connect (OSTI)

    Gao, Zhiming [ORNL] [ORNL; LaClair, Tim J [ORNL] [ORNL; Daw, C Stuart [ORNL] [ORNL; Smith, David E [ORNL] [ORNL; Franzese, Oscar [ORNL] [ORNL

    2014-01-01T23:59:59.000Z

    We present simulated fuel economy and emissions city transit buses powered by conventional diesel engines and diesel-hybrid electric powertrains of varying size. Six representative city drive cycles were included in the study. In addition, we included previously published aftertreatment device models for control of CO, HC, NOx, and particulate matter (PM) emissions. Our results reveal that bus hybridization can significantly enhance fuel economy by reducing engine idling time, reducing demands for accessory loads, exploiting regenerative braking, and shifting engine operation to speeds and loads with higher fuel efficiency. Increased hybridization also tends to monotonically reduce engine-out emissions, but trends in the tailpipe (post-aftertreatment) emissions involve more complex interactions that significantly depend on motor size and drive cycle details.

  5. Designing New Transit Bus Garages to be Fuel Flexible

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

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Home Page on Google Bookmark EERE: Alternative Fuels Data Center Home Page on Delicious Rank EERE: Alternative Fuels Data Center Home PageStationGreenhouse GasCalifornia State0 Cleanr Clean

  6. A Simple, Accurate Model for Alkyl Adsorption on Late Transition...

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

    Simple, Accurate Model for Alkyl Adsorption on Late Transition Metals. A Simple, Accurate Model for Alkyl Adsorption on Late Transition Metals. Abstract: A simple model that...

  7. Agent-Based Modeling and Simulation for Hydrogen Transition Analysis...

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

    Agent-Based Modeling and Simulation for Hydrogen Transition Analysis Agent-Based Modeling and Simulation for Hydrogen Transition Analysis Presentation on Agent-Based Modeling and...

  8. Fuel Cell Buses in U.S. Transit Fleets: Current Status 2013

    SciTech Connect (OSTI)

    Eudy, L.; Gikakis, C.

    2013-12-01T23:59:59.000Z

    This report is the seventh in an annual series of reports that summarize the progress of fuel cell electric bus (FCEB) development in the United States and discuss the achievements and challenges of introducing fuel cell propulsion in transit. The report also provides a snapshot of current FCEB performance results from August 2012 through July 2013 for five FCEB demonstrations at four transit agencies.

  9. Used Fuel Testing Transportation Model

    SciTech Connect (OSTI)

    Ross, Steven B.; Best, Ralph E.; Maheras, Steven J.; Jensen, Philip J.; England, Jeffery L.; LeDuc, Dan

    2014-09-24T23:59:59.000Z

    This report identifies shipping packages/casks that might be used by the Used Nuclear Fuel Disposition Campaign Program (UFDC) to ship fuel rods and pieces of fuel rods taken from high-burnup used nuclear fuel (UNF) assemblies to and between research facilities for purposes of evaluation and testing. Also identified are the actions that would need to be taken, if any, to obtain U.S. Nuclear Regulatory (NRC) or other regulatory authority approval to use each of the packages and/or shipping casks for this purpose.

  10. Chemical Kinetic Modeling of Fuels

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

    optimization of fuel formulations and engine design: * Potential for replacement of petroleum, greater than 5% by 2018 * Increase heavy duty engine thermal efficiency to 55% by...

  11. Timing is everything : along the fossil fuel transition pathway.

    SciTech Connect (OSTI)

    Kobos, Peter Holmes; Walker, La Tonya Nicole; Malczynski, Leonard A.

    2013-10-01T23:59:59.000Z

    People save for retirement throughout their career because it is virtually impossible to save all you'll need in retirement the year before you retire. Similarly, without installing incremental amounts of clean fossil, renewable or transformative energy technologies throughout the coming decades, a radical and immediate change will be near impossible the year before a policy goal is set to be in place. Therefore, our research question is,To meet our desired technical and policy goals, what are the factors that affect the rate we must install technology to achieve these goals in the coming decades?' Existing models do not include full regulatory constraints due to their often complex, and inflexible approaches to solve foroptimal' engineering instead ofrobust' and multidisciplinary solutions. This project outlines the theory and then develops an applied software tool to model the laboratory-to-market transition using the traditional technology readiness level (TRL) framework, but develops subsequent and a novel regulatory readiness level (RRL) and market readiness level (MRL). This tool uses the ideally-suited system dynamics framework to incorporate feedbacks and time delays. Future energy-economic-environment models, regardless of their programming platform, may adapt this software model component framework ormodule' to further vet the likelihood of new or innovative technology moving through the laboratory, regulatory and market space. The prototype analytical framework and tool, called the Technology, Regulatory and Market Readiness Level simulation model (TRMsim) illustrates the interaction between technology research, application, policy and market dynamics as they relate to a new or innovative technology moving from the theoretical stage to full market deployment. The initial results that illustrate the model's capabilities indicate for a hypothetical technology, that increasing the key driver behind each of the TRL, RRL and MRL components individually decreases the time required for the technology to progress through each component by 63, 68 and 64%, respectively. Therefore, under the current working assumptions, to decrease the time it may take for a technology to move from the conceptual stage to full scale market adoption one might consider expending additional effort to secure regulatory approval and reducing the uncertainty of the technology's demand in the marketplace.

  12. DYNAMIC MODELING PROTON EXCHANGE MEMBRANE FUEL CELL

    E-Print Network [OSTI]

    Mease, Kenneth D.

    DYNAMIC MODELING PROTON EXCHANGE MEMBRANE FUEL CELL OVERVIEW Current/Completed Plug Power to garner SCAQMD funding for fuel cell testing GenCore system is sensitive to diluents · As built design stream to compensate for removal of EGR · Functionality of the modified GenCore Fuel Cell system

  13. ac transit fuel: Topics by E-print Network

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

    gamma ray upon decay. We find that pressurized light-water-reactors fueled with LEU-thorium fuel at high burnup (70 MWdkg) produce U-233 with U-232 contamination levels of...

  14. Hydrogen Fuel Cell Bus Evaluation for California Transit Agencies |

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

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Home Page on Google Bookmark EERE: Alternative Fuels Data Center Home Page onYouTube YouTube Note: Since the.pdfBreaking of Blythe SolarContamination Detector WorkshopHydrogen

  15. Alternative Fuels Data Center: State Requirements Boost the Transition to

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

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative1 First Use of Energy for All Purposes (Fuel and Nonfuel), 2002; Level: National5Sales for4,645U.S. DOE Office511041cloth DocumentationProductsAlternative FuelsSanta Fe Metro Fleet Runs on NaturalRunAlternative

  16. Integrated Market Modeling of Hydrogen Transition Scenarios with...

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

    Integrated Market Modeling of Hydrogen Transition Scenarios with HyTrans Integrated Market Modeling of Hydrogen Transition Scenarios with HyTrans Presentation by Paul Leiby of Oak...

  17. Modeling the Nuclear Fuel Cycle

    SciTech Connect (OSTI)

    Jacob J. Jacobson; Mary Lou Dunzik-Gougar; Christopher A. Juchau

    2010-08-01T23:59:59.000Z

    A review of existing nuclear fuel cycle systems analysis codes was performed to determine if any existing codes meet technical and functional requirements defined for a U.S. national program supporting the global and domestic assessment, development and deployment of nuclear energy systems. The program would be implemented using an interconnected architecture of different codes ranging from the fuel cycle analysis code, which is the subject of the review, to fundamental physical and mechanistic codes. Four main functions are defined for the code: (1) the ability to characterize and deploy individual fuel cycle facilities and reactors in a simulation, while discretely tracking material movements, (2) the capability to perform an uncertainty analysis for each element of the fuel cycle and an aggregate uncertainty analysis, (3) the inclusion of an optimization engine able to optimize simultaneously across multiple objective functions, and (4) open and accessible code software and documentation to aid in collaboration between multiple entities and facilitate software updates. Existing codes, categorized as annualized or discrete fuel tracking codes, were assessed according to the four functions and associated requirements. These codes were developed by various government, education and industrial entities to fulfill particular needs. In some cases, decisions were made during code development to limit the level of detail included in a code to ease its use or to focus on certain aspects of a fuel cycle to address specific questions. The review revealed that while no two of the codes are identical, they all perform many of the same basic functions. No code was able to perform defined function 2 or several requirements of functions 1 and 3. Based on this review, it was concluded that the functions and requirements will be met only with development of a new code, referred to as GENIUS.

  18. Analysis Models and Tools: Systems Analysis of Hydrogen and Fuel...

    Office of Environmental Management (EM)

    and Fuel Cells Analysis Models and Tools: Systems Analysis of Hydrogen and Fuel Cells The Fuel Cell Technologies Office's systems analysis program uses a consistent set of models...

  19. Evaluation of fuel rod characterization for transient fuel modeling 

    E-Print Network [OSTI]

    Bechler, Eric Wayne

    1989-01-01T23:59:59.000Z

    P+ (g1+ g2) + brad (4) 17 where hgap is the gap conductance ks is the conductivity of the gas mixture tsap is the gap width gt+g2 are the temperature jump distances at the clad inner and fuel outer surfaces The temperature jump distances... the temperature of the fuel increases dramatically. & The model defines the total cumulative release during time t to be t 2 ) ( ) d ~ 1- exp[-m rt (r (t) - r(u))] m=1 m tt 0 (6) where rt r(t) = J D'(u) du 0 R is the total fission gas release during time...

  20. BC Transit Fuel Cell Bus Project: Evaluation Results Report

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

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative1 First Use of Energy for All Purposes (Fuel and Nonfuel), 2002; Level: National5Sales for4,645U.S. DOE Office511041cloth DocumentationProductsAlternativeOperationalAugust Nazim Ali Bharmal, Comparisons ofBBQ - Is

  1. Alternative Fuels Data Center: Delaware Transit Corporation Adds Propane

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

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative1 First Use of Energy for All Purposes (Fuel and Nonfuel), 2002; Level: National5Sales for4,645 3,625govInstrumentstdmadapInactiveVisiting the TWP TWP RelatedCellulase C.Tier 2North Carolina for

  2. BC Transit Fuel Cell Bus Project Evaluation Results: Second Report

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

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative1 First Use of Energy for All Purposes (Fuel and Nonfuel), 2002; Level: National5Sales for4,645 3,625govInstrumentstdmadapInactiveVisiting the TWP TWPAlumniComplex historian ... B&WBen LarsonBBC Video LooksBC

  3. Quantum Phase Transition in a Graphene Model

    E-Print Network [OSTI]

    Simon Hands; Costas Strouthos

    2008-08-20T23:59:59.000Z

    We present results for the equation of state of a graphene-like model in an effort to understand the properties of its quantum phase transition. The N_f fermion species interact through a three dimensional instantaneous Coulomb potential. Since there are no reliable analytical tools that work for all values of N_f and the coupling constant g, we rely on Monte Carlo simulations to calculate the critical properties of the model near the phase transition. We consider the four-component formulation for the fermion fields, which arises naturally as the continuum limit of the staggered fermion construction in (2+1) dimensions. In the limit of infinitely strong Coulomb interaction, the system undergoes a quantum phase transition at a critical number of fermion species N_fc ~ 4.7. We also calculate the values of the critical exponents at the quantum phase transition.

  4. Fossil fuels supplies modeling and research

    SciTech Connect (OSTI)

    Leiby, P.N.

    1996-06-01T23:59:59.000Z

    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.

  5. SunLine Transit Agency Fuel Cell Transit Bus: Fourth Evaluation Report and

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

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Home Page on Google Bookmark EERE: Alternative Fuels DataDepartment of Energy Your Density Isn'tOriginEducationVideoStrategic Safety GoalsEnergy Begins Extended Testing of

  6. Fuel Cell Transit Buses: ThunderPower Bus Evaluation at SunLine Transit

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

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Home Page on Google Bookmark EERE: Alternative Fuels DataDepartment of Energy Your Density Isn't YourTransport inEnergy0.pdfTechnologies Program (FCTP)Overview FuelStorage, andAgency |

  7. Fuel Cell Transit Bus Coordination and Evaluation Plan California Fuel Cell

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

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Home Page on Google Bookmark EERE: Alternative Fuels DataDepartment of Energy Your Density Isn't YourTransport inEnergy0.pdfTechnologies Program (FCTP)Overview FuelStorage, and

  8. Modeling of solid oxide fuel cells

    E-Print Network [OSTI]

    Lee, Won Yong, S.M. Massachusetts Institute of Technology

    2006-01-01T23:59:59.000Z

    A comprehensive membrane-electrode assembly (MEA) model of Solid Oxide Fuel Cell (SOFC)s is developed to investigate the effect of various design and operating conditions on the cell performance and to examine the underlying ...

  9. Fuel economy testing of six 40-foot transit buses. Final report Aug 82-Mar 83

    SciTech Connect (OSTI)

    Francis, G.A.; Nelson, S.R.

    1983-03-01T23:59:59.000Z

    The importance of life-cycle cost analyses in transit bus procurement is recognized by the industry and has been a Congressional requirement for grantees. This report documents a program of fuel economy testing of six standard 40-foot buses. The main purpose of this series of tests is to assist transit authorities and bus suppliers by providing accurate comparable fuel consumption data on transit buses produced by different manufacturers. Six buses were selected by the manufacturers and supplied for testing by six transit properties directly from revenue service. This report makes the data available to the industry for discretionary use in estimating life-cycle costs. A list of bus manufacturers and the supplying transit system is provided.

  10. AC Transit Demos Three Prototype Fuel Cell Buses | Department of Energy

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

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Home Page on Google Bookmark EERE: Alternative Fuels DataDepartment of Energy Your Density Isn't Your Destiny: The Future of1 A Strategic Framework for SMRA View from the-1AssessmentAC Transit

  11. Alameda-Contra Costa Transit District Fuel Cell Transit Buses: Evalluation

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

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Home Page on Google Bookmark EERE: Alternative Fuels DataDepartment of Energy Your Density Isn't Your Destiny: The Future of1Albuquerque, NM - Building Americaof42.2Air-SourceAustin,Results

  12. SunLine Transit Agency Fuel Cell Transit Bus: Fifth Evaluation Report |

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

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Home Page on Google Bookmark EERE: Alternative Fuels DataDepartment of Energy Your Density Isn'tOriginEducationVideoStrategic Safety GoalsEnergy Begins Extended Testing of HybridTests

  13. SunLine Transit Agency Fuel Cell Transit Bus: Fourth Evaluation Report and

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

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Home Page on Google Bookmark EERE: Alternative Fuels DataDepartment of Energy Your Density Isn'tOriginEducationVideoStrategic Safety GoalsEnergy Begins Extended Testing ofAppendices |

  14. Microgravity Flow Regime Transition Modeling 

    E-Print Network [OSTI]

    Shephard, Adam M.

    2010-07-14T23:59:59.000Z

    ................... 18 14 Colin and Fabre (1995) 0.0190 m diameter air-water data set ................... 18 15 Comparison of the Dukler et al. (1988) and Bousman (1994) 0.0127 m diameter air-water system data sets... ........................................................................................................ 67 33 Colin and Fabre (1995) 0.0190 m diameter air-water data set with models ........................................................................................................ 68 34 Dukler et al. (1988) 0.0127 m diameter air-water data...

  15. Microgravity Flow Regime Transition Modeling

    E-Print Network [OSTI]

    Shephard, Adam M.

    2010-07-14T23:59:59.000Z

    by Ghrist (2008) where an existing computer code, RELAP 5-3D, demonstrated the limitations of currently available computational modeling when applied to zero-g conditions. 1.2.2 EXPERIMENTAL APPARATUS All flow regime mapping experiments consist of a... ............................................................... 9 2.3 Dukler et al. 1988/Janicot 1988 ............................................. 9 2.4 Colin et al. 1991 .................................................................... 11 2.5 Huckerby and Rezkallah 1992...

  16. Mathematical modeling of solid oxide fuel cells using hydrocarbon fuels

    E-Print Network [OSTI]

    Lee, Won Yong, Ph. D. Massachusetts Institute of Technology

    2012-01-01T23:59:59.000Z

    Solid oxide fuel cells (SOFCs) are high efficiency conversion devices that use hydrogen or light hydrocarbon (HC) fuels in stationary applications to produce quiet and clean power. While successful, HC-fueled SOFCs face ...

  17. SunLine Transit Agency Advanced Technology Fuel Cell Bus Evaluation: Fourth Results Report

    SciTech Connect (OSTI)

    Eudy, L.; Chandler, K.

    2013-01-01T23:59:59.000Z

    SunLine Transit Agency, which provides public transit services to the Coachella Valley area of California, has demonstrated hydrogen and fuel cell bus technologies for more than 10 years. In May 2010, SunLine began demonstrating the advanced technology (AT) fuel cell bus with a hybrid electric propulsion system, fuel cell power system, and lithium-based hybrid batteries. This report describes operations at SunLine for the AT fuel cell bus and five compressed natural gas buses. The U.S. Department of Energy's National Renewable Energy Laboratory (NREL) is working with SunLine to evaluate the bus in real-world service to document the results and help determine the progress toward technology readiness. NREL has previously published three reports documenting the operation of the fuel cell bus in service. This report provides a summary of the results with a focus on the bus operation from February 2012 through November 2012.

  18. SunLine Transit Agency Advanced Technology Fuel Cell Bus Evaluation: First Results Report

    SciTech Connect (OSTI)

    Eudy, L.; Chandler, K.

    2011-03-01T23:59:59.000Z

    This report describes operations at SunLine Transit Agency for their newest prototype fuel cell bus and five compressed natural gas (CNG) buses. In May 2010, SunLine began operating its sixth-generation hydrogen fueled bus, an Advanced Technology (AT) fuel cell bus that incorporates the latest design improvements to reduce weight and increase reliability and performance. The agency is collaborating with the U.S. Department of Energy's (DOE) National Renewable Energy Laboratory (NREL) to evaluate the bus in revenue service. This report provides the early data results and implementation experience of the AT fuel cell bus since it was placed in service.

  19. Advancement in Fuel Spray and Combustion Modeling for Compression...

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

    Advancement in Fuel Spray and Combustion Modeling for Compression Ignition Engine Applications Advancement in Fuel Spray and Combustion Modeling for Compression Ignition Engine...

  20. Supercomputers Fuel Global High-Resolution Climate Models

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

    Supercomputers Fuel Global High-Resolution Climate Models Supercomputers Fuel Global High-Resolution Climate Models Berkeley Lab Researcher Says Climate Science is Entering New...

  1. Update on Transition to Ultra-Low-Sulfur Diesel Fuel (released in AEO2006)

    Reports and Publications (EIA)

    2006-01-01T23:59:59.000Z

    On November 8, 2005, the Environmental Protection Agency (EPA) Administrator signed a direct final rule that will shift the retail compliance date for offering ultra-low sulfur diesel (ULSD) for highway use from September 1, 2006, to October 15, 2006. The change will allow more time for retail outlets and terminals to comply with the new 15 parts per million (ppm) sulfur standard, providing time for entities in the diesel fuel distribution system to flush higher sulfur fuel out of the system during the transition. Terminals will have until September 1, 2006, to complete their transitions to ULSD. The previous deadline was July 15, 2006.

  2. Fuel Cell Buses in U.S. Transit Fleets: Current Status 2010

    SciTech Connect (OSTI)

    Eudy, L.; Chandler, K.; Gigakis, C.

    2010-11-01T23:59:59.000Z

    This status report, fourth in a series of annual status reports from the U.S. Department of Energy's National Renewable Energy Laboratory, summarizes progress and accomplishments from demonstrations of fuel cell transit buses in the United States. This year's assessment report provides the results from the fifth year of operation of five Van Hool, ISE, and UTC Power fuel cell buses operating at AC Transit, SunLine, and CTTRANSIT. The achievements and challenges of this bus design, implementation, and operating are presented, with a focus on the next steps for implementing larger numbers and new and different designs of fuel cell buses. The major positive result from nearly five years of operation is the dramatic increase in reliability experienced for the fuel cell power system.

  3. Evaluation of fuel rod characterization for transient fuel modeling

    E-Print Network [OSTI]

    Bechler, Eric Wayne

    1989-01-01T23:59:59.000Z

    . The transient fuel performance computer code incorporated in this study, FREY-01, is a general purpose fuel rod evaluation code developed for the transient analyses of LWR fuel rods by the Electric Power Research Institute (EPRI). Although FREY-01.... The predictions by the codes were compared with experimental data for fuel elements from commercial and test reactors. FREY-01, developed by ANATECH Research Corporation under the sponsorship of the Electric Power Research Institute (EPRI), is a general purpose...

  4. Fuel Cell Buses in U.S. Transit Fleets: Current Status 2012

    SciTech Connect (OSTI)

    Eudy, L.; Chander, K.; Gikakis, C.

    2012-11-01T23:59:59.000Z

    This report is the sixth in an annual series of reports that summarize the progress of fuel cell electric bus (FCEB) development in the United States and discuss the achievements and challenges of introducing fuel cell propulsion in transit. The report also provides a snapshot of current FCEB performance results over the last year. There are 25 active FCEBs in demonstrations this year at eight locations.

  5. Testing Transition State Theory on Kac-Zwanzig Model

    E-Print Network [OSTI]

    Van Den Eijnden, Eric

    Testing Transition State Theory on Kac-Zwanzig Model G. Ariel and E. Vanden-Eijnden Courant A variant of the Kac-Zwanzig model is used to test the prediction of transition state theory (TST) and variational transition state theory (VTST). The model describes the evolution of a distinguished particle

  6. Fuel Puddle Model and AFR Compensator for Gasoline-Ethanol Blends in Flex-Fuel Engines*

    E-Print Network [OSTI]

    Stefanopoulou, Anna

    Fuel Puddle Model and AFR Compensator for Gasoline-Ethanol Blends in Flex-Fuel Engines* Kyung for gasoline-ethanol blends is, thus, necessary for the purpose of air-to-fuel ratio control. In this paper, we- ration, air-to-fuel ratio control, gasoline-ethanol blend, flex-fuel vehicles I. INTRODUCTION Currently

  7. Chemical Kinetic Modeling of Non-Petroleum Based Fuels

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

    kinetic models for fuel components and their mixtures are a critical need to enable optimization of fuel formulations for high engine efficiency and very low emissions Targets:...

  8. Advancement in Fuel Spray and Combustion Modeling for Compression...

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

    Applications Advancement in Fuel Spray and Combustion Modeling for Compression Ignition Engine Applications 2013 DOE Hydrogen and Fuel Cells Program and Vehicle Technologies...

  9. Water Transport in PEM Fuel Cells: Advanced Modeling, Material...

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

    Testing and Design Optimization Water Transport in PEM Fuel Cells: Advanced Modeling, Material Selection, Testing and Design Optimization Part of a 100 million fuel cell award...

  10. Fuel Cell System Improvement for Model-Based Diagnosis Analysis

    E-Print Network [OSTI]

    Paris-Sud XI, Université de

    Fuel Cell System Improvement for Model-Based Diagnosis Analysis Philippe Fiani & Michel Batteux of a model of a fuel cell system, in order to make it usable for model- based diagnosis methods. A fuel cell for the fuel cell stack but also for the system environment. In this paper, we present an adapted library which

  11. Agent-Based Modeling and Simulation for Hydrogen Transition Analysis

    Broader source: Energy.gov [DOE]

    Presentation on Agent-Based Modeling and Simulation for Hydrogen Transition Analysis given by Marianne Mintz of ANL during the DOE Hydrogen Transition Analysis Workshop on January 26, 2006.

  12. Fuel Used for Off-Road Recreation: A Reassessment of the Fuel Use Model

    E-Print Network [OSTI]

    Fuel Used for Off-Road Recreation: A Reassessment of the Fuel Use Model Stacy C. Davis Lorena F. Truett Patricia S. Hu #12;ORNL/TM-1999/100 Fuel Used for Off-Road Recreation: A Reassessment of the Fuel.S. Department of Energy under Contract No. DE-AC05-96OR22464 #12;#12;Fuel Used for Off-Road Recreation

  13. SunLine Transit Agency Advanced Technology Fuel Cell Bus Evaluation: Second Results Report and Appendices

    SciTech Connect (OSTI)

    Eudy, L.; Chandler, K.

    2011-10-01T23:59:59.000Z

    This report describes operations at SunLine Transit Agency for their newest prototype fuel cell bus and five compressed natural gas (CNG) buses. In May 2010, SunLine began operating its sixth-generation hydrogen fueled bus, an Advanced Technology (AT) fuel cell bus that incorporates the latest design improvements to reduce weight and increase reliability and performance. The agency is collaborating with the U.S. Department of Energy's (DOE) National Renewable Energy Laboratory (NREL) to evaluate the bus in revenue service. This is the second results report for the AT fuel cell bus since it was placed in service, and it focuses on the newest data analysis and lessons learned since the previous report. The appendices, referenced in the main report, provide the full background for the evaluation. They will be updated as new information is collected but will contain the original background material from the first report.

  14. SunLine Transit Agency Advanced Technology Fuel Cell Bus Evaluation: Third Results Reports

    SciTech Connect (OSTI)

    Eudy, L.; Chandler, K.

    2012-05-01T23:59:59.000Z

    This report describes operations at SunLine Transit Agency for their newest prototype fuel cell bus and five compressed natural gas (CNG) buses. In May 2010, SunLine began operating its sixth-generation hydrogen fueled bus, an Advanced Technology (AT) fuel cell bus that incorporates the latest design improvements to reduce weight and increase reliability and performance. The agency is collaborating with the U.S. Department of Energy's (DOE) National Renewable Energy Laboratory (NREL) to evaluate the bus in revenue service. NREL has previously published two reports documenting the operation of the fuel cell bus in service. This report provides a summary of the results with a focus on the bus operation from July 2011 through January 2012.

  15. Progress in Chemical Kinetic Modeling for Surrogate Fuels

    SciTech Connect (OSTI)

    Pitz, W J; Westbrook, C K; Herbinet, O; Silke, E J

    2008-06-06T23:59:59.000Z

    Gasoline, diesel, and other alternative transportation fuels contain hundreds to thousands of compounds. It is currently not possible to represent all these compounds in detailed chemical kinetic models. Instead, these fuels are represented by surrogate fuel models which contain a limited number of representative compounds. We have been extending the list of compounds for detailed chemical models that are available for use in fuel surrogate models. Detailed models for components with larger and more complicated fuel molecular structures are now available. These advancements are allowing a more accurate representation of practical and alternative fuels. We have developed detailed chemical kinetic models for fuels with higher molecular weight fuel molecules such as n-hexadecane (C16). Also, we can consider more complicated fuel molecular structures like cyclic alkanes and aromatics that are found in practical fuels. For alternative fuels, the capability to model large biodiesel fuels that have ester structures is becoming available. These newly addressed cyclic and ester structures in fuels profoundly affect the reaction rate of the fuel predicted by the model. Finally, these surrogate fuel models contain large numbers of species and reactions and must be reduced for use in multi-dimensional models for spark-ignition, HCCI and diesel engines.

  16. Modeling-Computer Simulations At Walker-Lane Transitional Zone...

    Open Energy Info (EERE)

    navigation, search GEOTHERMAL ENERGYGeothermal Home Exploration Activity: Modeling-Computer Simulations At Walker-Lane Transitional Zone Region (Biasi, Et Al., 2009) Exploration...

  17. Modeling-Computer Simulations At Walker-Lane Transitional Zone...

    Open Energy Info (EERE)

    navigation, search GEOTHERMAL ENERGYGeothermal Home Exploration Activity: Modeling-Computer Simulations At Walker-Lane Transitional Zone Region (Pritchett, 2004) Exploration...

  18. The transition to hydrogen as a transportation fuel: Costs and infrastructure requirements

    SciTech Connect (OSTI)

    Schock, R.N.; Berry, G.D.; Ramback, G.D.; Smith, J.R.

    1996-03-20T23:59:59.000Z

    Hydrogen fuel, used in an internal combustion engine optimized for maximum efficiency and as part of a hybrid-electric vehicle, will give excellent performance and range with emissions below one-tenth the ultra-low emission vehicle standards being considered in California as Equivalent Zero Emission Vehicles. These vehicles can also be manufactured with increased but not excessive cost. Hydrogen-fueled engines have demonstrated indicated efficiencies of more than 50% under lean operation. Combining optimized engines and other advanced components, the overall vehicle efficiency should approach 40%, compared with 13% for a conventional vehicle in the urban driving cycle. The optimized engine-generator unit is the mechanical equivalent of the fuel cell but at a cost competitive with today`s engines. The increased efficiency of hybrid-electric vehicles now makes hydrogen fuel competitive with today`s conventional vehicles. Conservative analysis of the infrastructure options to support a transition to a hydrogen-fueled light-duty fleet indicates that hydrogen may be utilized at a total cost comparable to the 3.1 cents/km U.S. vehicle operators pay today while using conventional automobiles. Both on-site production by electrolysis or reforming of natural gas and liquid hydrogen distribution offer the possibility of a smooth transition by taking advantage of existing large-scale energy infrastructures. Eventually, renewable sources of electricity and scalable methods of making hydrogen will have lower costs than today. With a hybrid-electric propulsion system, the infrastructure to supply hydrogen and the vehicles to use it can be developed today and thus be in place when fuel cells become economical for vehicle use.

  19. Design optimization and analysis of coated particle fuel using advanced fuel performance modeling techniques

    E-Print Network [OSTI]

    Soontrapa, Chaiyod

    2005-01-01T23:59:59.000Z

    Modifying material properties provides another approach to optimize coated particle fuel used in pebble bed reactors. In this study, the MIT fuel performance model (TIMCOAT) was applied after benchmarking against the ...

  20. Solid Oxide Fuel Cell: Perspective of Dynamic Modeling and Control

    E-Print Network [OSTI]

    Huang, Biao

    Solid Oxide Fuel Cell: Perspective of Dynamic Modeling and Control Biao Huang Yutong Qi Monjur: This paper presents a review of state-of-the-art solid oxide fuel cells (SOFC), from perspective of dynamic. Keywords: Solid Oxide Fuel Cell, Control Relevant Model, Model Predictive Control 1. INTRODUCTION Today

  1. COMPUTATIONAL FLUID DYNAMICS MODELING OF SOLID OXIDE FUEL CELLS

    E-Print Network [OSTI]

    COMPUTATIONAL FLUID DYNAMICS MODELING OF SOLID OXIDE FUEL CELLS Ugur Pasaogullari and Chao-dimensional model has been developed to simulate solid oxide fuel cells (SOFC). The model fully couples current density operation. INTRODUCTION Solid oxide fuel cells (SOFC) are among possible candidates

  2. Fundamental Models for Fuel Cell Engineering Chao-Yang Wang*

    E-Print Network [OSTI]

    Diagnostics 4757 4.4. Model Validation 4758 4.5. Summary and Outlook 4760 5. Solid Oxide Fuel Cells 4760 5Fundamental Models for Fuel Cell Engineering Chao-Yang Wang* Departments of Mechanical Engineering Fuel Cell Dynamics 4727 2.1. CFCD Model Equations 4728 2.2. Computational Aspects 4729 2.2.1. General

  3. Global quantum discord and quantum phase transition in XY model

    E-Print Network [OSTI]

    Si-Yuan Liu; Yu-Ran Zhang; Wen-Li Yang; Heng Fan

    2014-05-20T23:59:59.000Z

    We study the relationship between the behavior of global quantum correlations and quantum phase transitions in XY model. We find that the two kinds of phase transitions in the studied model can be characterized by the features of global quantum discord (GQD) and the corresponding quantum correlations. We demonstrate that the maximum of the sum of all the nearest neighbor bipartite GQDs is effective and accurate for signaling the Ising quantum phase transition, in contrast, the sudden change of GQD is very suitable for characterizing another phase transition in the XY model. This may shed lights on the study of properties of quantum correlations in different quantum phases.

  4. Modelling Microscale Fuel Cells Aimy Ming Jii Bazylak

    E-Print Network [OSTI]

    Victoria, University of

    Modelling Microscale Fuel Cells by Aimy Ming Jii Bazylak B.E., University of Saskatchewan, 2003 cell designs using computational fluid dynamics (CFD). Two microscale fuel cell systems are considered in this work: the membraneless microfluidic fuel cell and a planar array of integrated fuel cells. A concise

  5. Implementing SPC in a Simulation Model for Manufacturing Transitions

    E-Print Network [OSTI]

    Nembhard, Harriet Black

    - ~(~-;::;: Implementing SPC in a Simulation Model for Manufacturing Transitions Harriet Black and 2). Product quality often suffers during such transition periods. Statistical process control (SPC the design and development of an integrated SPC and simulation model. Figure 1 shows a screen snapshot

  6. Modelling and control strategy development for fuel cell electric vehicles

    E-Print Network [OSTI]

    Peng, Huei

    Modelling and control strategy development for fuel cell electric vehicles Andreas Schell b , Huei applicable to the development of fuel cell electric vehicles (FCEVs) and hybrid electric vehicles (HEVs reserved. Keywords: Fuel cell electric vehicle; Hybrid vehicles; Modelling 1. Introduction Advanced

  7. Mesoscale modeling of phase transition dynamics of thermoresponsive polymers

    E-Print Network [OSTI]

    Li, Zhen; Li, Xuejin; Karniadakis, George Em

    2015-01-01T23:59:59.000Z

    We present a non-isothermal mesoscopic model for investigation of the phase transition dynamics of thermoresponsive polymers. Since this model conserves energy in the simulations, it is able to correctly capture not only the transient behavior of polymer precipitation from solvent, but also the energy variation associated with the phase transition process. Simulations provide dynamic details of the thermally induced phase transition and confirm two different mechanisms dominating the phase transition dynamics. A shift of endothermic peak with concentration is observed and the underlying mechanism is explored.

  8. Electroweak phase transition in a model with gauged lepton number

    E-Print Network [OSTI]

    Alfredo Aranda; Enrique Jiménez; Carlos A. Vaquera-Araujo

    2015-01-16T23:59:59.000Z

    In this work we study the electroweak phase transition in a model with gauged lepton number. Here, a family of vector-like leptons is required in order to cancel the gauge anomalies. Furthermore, these leptons can play an important role in the transition process. We find that this framework is able to provide a strong transition, but only for a very limited number of cases.

  9. Energy Transition Model | Open Energy Information

    Open Energy Info (EERE)

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Home Page onYou are now leaving Energy.gov You are now leaving Energy.gov You are being directedAnnual SiteofEvaluating A PotentialJump to:Emminol JumpEnergy SystemSystems Network ESN

  10. Liquid Fuels Market Model (LFMM) Unveiling LFMM

    Gasoline and Diesel Fuel Update (EIA)

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative1 First Use of Energy for All Purposes (Fuel and Nonfuel), 2002; Level: National5Sales for On-Highway4,1,50022,3,,,,6,1,9,1,50022,3,,,,6,1,Decade EnergyTennesseeYear Jan Next MECS will be fieldedYear

  11. A methodology for assessing the market benefits of alternative motor fuels: The Alternative Fuels Trade Model

    SciTech Connect (OSTI)

    Leiby, P.N.

    1993-09-01T23:59:59.000Z

    This report describes a modeling methodology for examining the prospective economic benefits of displacing motor gasoline use by alternative fuels. The approach is based on the Alternative Fuels Trade Model (AFTM). AFTM development was undertaken by the US Department of Energy (DOE) as part of a longer term study of alternative fuels issues. The AFTM is intended to assist with evaluating how alternative fuels may be promoted effectively, and what the consequences of substantial alternative fuels use might be. Such an evaluation of policies and consequences of an alternative fuels program is being undertaken by DOE as required by Section 502(b) of the Energy Policy Act of 1992. Interest in alternative fuels is based on the prospective economic, environmental and energy security benefits from the substitution of these fuels for conventional transportation fuels. The transportation sector is heavily dependent on oil. Increased oil use implies increased petroleum imports, with much of the increase coming from OPEC countries. Conversely, displacement of gasoline has the potential to reduce US petroleum imports, thereby reducing reliance on OPEC oil and possibly weakening OPEC`s ability to extract monopoly profits. The magnitude of US petroleum import reduction, the attendant fuel price changes, and the resulting US benefits, depend upon the nature of oil-gas substitution and the supply and demand behavior of other world regions. The methodology applies an integrated model of fuel market interactions to characterize these effects.

  12. Solid oxide fuel cell with transitioned cross-section for improved anode gas management at the open end

    DOE Patents [OSTI]

    Zafred, Paolo R. (Murrysville, PA); Draper, Robert (Pittsburgh, PA)

    2012-01-17T23:59:59.000Z

    A solid oxide fuel cell (400) is made having a tubular, elongated, hollow, active section (445) which has a cross-section containing an air electrode (452) a fuel electrode (454) and solid oxide electrolyte (456) between them, where the fuel cell transitions into at least one inactive section (460) with a flattened parallel sided cross-section (462, 468) each cross-section having channels (472, 474, 476) in them which smoothly communicate with each other at an interface section (458).

  13. Roadmap for Hydrogen and Fuel Cell Vehicles in California: A Transition Strategy through 2017

    E-Print Network [OSTI]

    Ogden, J; Cunningham, Joshua M; Nicholas, Michael A

    2010-01-01T23:59:59.000Z

    vehicle component costs (for fuel cells and hydrogenand cost issues for hydrogen and fuel cell vehicles, andFuel economy: • Fuel cell system cost: % of DOE 2015 Target

  14. Model Compound Studies of Fuel Cell Membrane Degradation

    Broader source: Energy.gov [DOE]

    Presentation on Model Compound Studies of Fuel Cell Membrane Degradation to the High Temperature Membrane Working Group Meeting held in Arlington, Virginia, May 26,2005.

  15. Water Transport in PEM Fuel Cells: Advanced Modeling, Material...

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

    Testing, and Design Optimization Water Transport in PEM Fuel Cells: Advanced Modeling, Material Selection, Testing, and Design Optimization This presentation, which focuses on...

  16. Direct Methanol Fuel Cell Experimental and Model Validation Study

    E-Print Network [OSTI]

    Wang, Chao-Yang

    Direct Methanol Fuel Cell Experimental and Model Validation Study M. Mench, J. Scott, S. Thynell boundary Fuel cell performance Current density distribution measurements Conclusions #12;3 Method, flow rate, species inlet and fuel cell temperature, and humidity. Transparent polycarbonate windows

  17. Computational Fuel Cell Research and SOFC Modeling at Penn State

    E-Print Network [OSTI]

    multidisciplinary research on fuel cells and advanced batteries for vehicle propulsion, distributed power generation science, multiphase transport, reactive flow, CFD modeling, experimental diagnostics, in- vehicle testing, DMFC, and SOFC #12;ECEC Facilities (>5,000 sq ft) Fuel Cell/Battery Experimental Labs Fuel Cell

  18. Wildland fire emissions, carbon, and climate: Modeling fuel consumption

    E-Print Network [OSTI]

    rate and pattern. Fuel consumption is the basic process that leads to heat absorbing emissions called evaluated with an independent, quality assured, fuel consumption data set. Furthermore, anecdotal evidenceWildland fire emissions, carbon, and climate: Modeling fuel consumption Roger D. Ottmar U

  19. Computational Modeling and Optimization of Proton Exchange Membrane Fuel Cells

    E-Print Network [OSTI]

    Victoria, University of

    Computational Modeling and Optimization of Proton Exchange Membrane Fuel Cells by Marc Secanell and Optimization of Proton Exchange Membrane Fuel Cells by Marc Secanell Gallart Bachelor in Engineering cells. In this thesis, a computational framework for fuel cell analysis and optimization is presented

  20. Transition in the two-dimensional step model: A Kosterlitz-Thouless transition in disguise Peter Olsson and Petter Holme

    E-Print Network [OSTI]

    Olsson, Peter

    Transition in the two-dimensional step model: A Kosterlitz-Thouless transition in disguise Peter Received 19 October 2000; published 11 January 2001 Evidence for a Kosterlitz-Thouless transition in the spin angles. We conclude that this is the reason for the Kosterlitz- Thouless transition in the 2D step

  1. Dynamic Modeling in Solid-Oxide Fuel Cells Controller Design

    SciTech Connect (OSTI)

    Lu, Ning; Li, Qinghe; Sun, Xin; Khaleel, Mohammad A.

    2007-06-28T23:59:59.000Z

    In this paper, a dynamic model of the solid-oxide fuel cell (SOFC) power unit is developed for the purpose of designing a controller to regulate fuel flow rate, fuel temperature, air flow rate, and air temperature to maintain the SOFC stack temperature, fuel utilization rate, and voltage within operation limits. A lumped model is used to consider the thermal dynamics and the electro-chemial dynamics inside an SOFC power unit. The fluid dynamics at the fuel and air inlets are considered by using the in-flow ramp-rates.

  2. The Electroweak Phase Transition in the Inert Doublet Model

    E-Print Network [OSTI]

    Nikita Blinov; Stefano Profumo; Tim Stefaniak

    2015-04-22T23:59:59.000Z

    We study the strength of a first-order electroweak phase transition in the Inert Doublet Model (IDM), where particle dark matter (DM) is comprised of the lightest neutral inert Higgs boson. We improve over previous studies in the description and treatment of the finite-temperature effective potential and of the electroweak phase transition. We focus on a set of benchmark models inspired by the key mechanisms in the IDM leading to a viable dark matter particle candidate, and illustrate how to enhance the strength of the electroweak phase transition by adjusting the masses of the yet undiscovered IDM Higgs states. We argue that across a variety of DM masses, obtaining a strong enough first-order phase transition is a generic possibility in the IDM. We find that due to direct dark matter searches and collider constraints, a sufficiently strong transition and a thermal relic density matching the universal DM abundance is possible only in the Higgs funnel regime.

  3. The Electroweak Phase Transition in the Inert Doublet Model

    E-Print Network [OSTI]

    Blinov, Nikita; Stefaniak, Tim

    2015-01-01T23:59:59.000Z

    We study the strength of a first-order electroweak phase transition in the Inert Doublet Model (IDM), where particle dark matter (DM) is comprised of the lightest neutral inert Higgs boson. We improve over previous studies in the description and treatment of the finite-temperature effective potential and of the electroweak phase transition. We focus on a set of benchmark models inspired by the key mechanisms in the IDM leading to a viable dark matter particle candidate, and illustrate how to enhance the strength of the electroweak phase transition by adjusting the masses of the yet undiscovered IDM Higgs states. We argue that across a variety of DM masses, obtaining a strong enough first-order phase transition is a generic possibility in the IDM. We find that due to direct dark matter searches and collider constraints, a sufficiently strong transition and a thermal relic density matching the universal DM abundance is possible only in the Higgs funnel regime.

  4. Rounding of the localization transition in model porous media

    E-Print Network [OSTI]

    Simon K. Schnyder; Markus Spanner; Felix Höfling; Thomas Franosch; Jürgen Horbach

    2014-11-07T23:59:59.000Z

    The generic mechanisms of anomalous transport in porous media are investigated by computer simulations of two-dimensional model systems. In order to bridge the gap between the strongly idealized Lorentz model and realistic models of porous media, two models of increasing complexity are considered: a cherry-pit model with hard-core correlations as well as a soft-potential model. An ideal gas of tracer particles inserted into these structures is found to exhibit anomalous transport which extends up to several decades in time. Also, the self-diffusion of the tracers becomes suppressed upon increasing the density of the systems. These phenomena are attributed to an underlying percolation transition. In the soft potential model the transition is rounded, since each tracer encounters its own critical density according to its energy. Therefore, the rounding of the transition is a generic occurrence in realistic, soft systems.

  5. Model of U3Si2 Fuel System using BISON Fuel Code

    SciTech Connect (OSTI)

    K. E. Metzger; T. W. Knight; R. L. Williamson

    2014-04-01T23:59:59.000Z

    This research considers the proposed advanced fuel system: U3Si2 combined with an advanced cladding. U3Si2 has a number of advantageous thermophysical properties, which motivate its use as an accident tolerant fuel. This preliminary model evaluates the behavior of U3Si2 using available thermophysical data to predict the cladding-fuel pellet temperature and stress using the fuel performance code: BISON. The preliminary results obtained from the U3Si2 fuel model describe the mechanism of Pellet-Clad Mechanical Interaction for this system while more extensive testing including creep testing of U3Si2 is planned for improved understanding of thermophysical properties for predicting fuel performance.

  6. Phase transition in linear sigma model and disoriented chiral condensate

    E-Print Network [OSTI]

    A. K. Chaudhuri

    2000-07-28T23:59:59.000Z

    We have investigated the phase transition and disoriented chiral condensate domain formation in linear sigma model. Solving the equation of motion for the sigma model fields in contact with a heat bath, we have shown that the fields undergo phase transition above a certain critical temperature(T_c). It was also shown that when the fields thermalised at temperature above T_c are cooled down sufficiently rapidly, disoriented chiral condensate domains are formed quite late in the evolution.

  7. Chemical Kinetic Modeling of Combustion of Automotive Fuels

    SciTech Connect (OSTI)

    Pitz, W J; Westbrook, C K; Silke, E J

    2006-11-10T23:59:59.000Z

    The objectives of this report are to: (1) Develop detailed chemical kinetic reaction models for components of fuels, including olefins and cycloalkanes used in diesel, spark-ignition and HCCI engines; (2) Develop surrogate mixtures of hydrocarbon components to represent real fuels and lead to efficient reduced combustion models; and (3) Characterize the role of fuel composition on production of emissions from practical automotive engines.

  8. Software Requirements Specification Verifiable Fuel Cycle Simulation (VISION) Model

    SciTech Connect (OSTI)

    D. E. Shropshire; W. H. West

    2005-11-01T23:59:59.000Z

    The purpose of this Software Requirements Specification (SRS) is to define the top-level requirements for a Verifiable Fuel Cycle Simulation Model (VISION) of the Advanced Fuel Cycle (AFC). This simulation model is intended to serve a broad systems analysis and study tool applicable to work conducted as part of the AFCI (including costs estimates) and Generation IV reactor development studies.

  9. Technical Approach and Plan for Transitioning Spent Nuclear Fuel (SNF) Project Facilities to the Environmental Restoration Program

    SciTech Connect (OSTI)

    SKELLY, W.A.

    1999-10-06T23:59:59.000Z

    This document describes the approach and process in which the 100-K Area Facilities are to be deactivated and transitioned over to the Environmental Restoration Program after spent nuclear fuel has been removed from the K Basins. It describes the Transition Project's scope and objectives, work breakdown structure, activity planning, estimated cost, and schedule. This report will be utilized as a planning document for project management and control and to communicate details of project content and integration.

  10. Stochastic Programming Model for Fuel Treatment Management 

    E-Print Network [OSTI]

    Kabli, Mohannad Reda A

    2014-04-28T23:59:59.000Z

    Due to the increased number and intensity of wild fires, the need for solutions that minimize the impact of fire are needed. Fuel treatment is one of the methods used to mitigate the effects of fire at a certain area. In this thesis, a two...

  11. Stochastic Programming Model for Fuel Treatment Management

    E-Print Network [OSTI]

    Kabli, Mohannad Reda A

    2014-04-28T23:59:59.000Z

    Due to the increased number and intensity of wild fires, the need for solutions that minimize the impact of fire are needed. Fuel treatment is one of the methods used to mitigate the effects of fire at a certain area. In this thesis, a two...

  12. Roadmap for Hydrogen and Fuel Cell Vehicles in California: A Transition Strategy through 2017

    E-Print Network [OSTI]

    Ogden, J; Cunningham, Joshua M; Nicholas, Michael A

    2010-01-01T23:59:59.000Z

    commitment to hydrogen and fuel cell vehicles has beenand storage R&D and fuel cell vehicle program, whilepower applications of fuel cells. Congress has recently re-

  13. A general holographic metal/superconductor phase transition model

    E-Print Network [OSTI]

    Yan Peng; Yunqi Liu

    2014-10-27T23:59:59.000Z

    We study the scalar condensation of a general holographic superconductor model in AdS black hole background away from the probe limit. We find the model parameters together with the scalar mass and backreaction can determine the order of phase transitions completely. In addition, we observe two types of discontinuities of the scalar operator in the case of first order phase transitions. We analyze in detail the effects of the scalar mass and backreaction on the formation of discontinuities and arrive at an approximate relation between the threshold model parameters. Furthermore, we obtain superconductor solutions corresponding to higher energy states and examine the stability of these superconductor solutions.

  14. A general holographic metal/superconductor phase transition model

    E-Print Network [OSTI]

    Yan Peng; Yunqi Liu

    2015-03-03T23:59:59.000Z

    We study the scalar condensation of a general holographic superconductor model in AdS black hole background away from the probe limit. We find the model parameters together with the scalar mass and backreaction can determine the order of phase transitions completely. In addition, we observe two types of discontinuities of the scalar operator in the case of first order phase transitions. We analyze in detail the effects of the scalar mass and backreaction on the formation of discontinuities and arrive at an approximate relation between the threshold model parameters. Furthermore, we obtain superconductor solutions corresponding to higher energy states and examine the stability of these superconductor solutions.

  15. Early Warning Signals for Critical Transitions: A Generalized Modeling Approach

    E-Print Network [OSTI]

    for early warning signals that integrates multiple sources of information and data about the system throughEarly Warning Signals for Critical Transitions: A Generalized Modeling Approach Steven J. Lade a previously published fisheries model. We regard our method as complementary to existing early warning signals

  16. Experimental Verification of a Cracked Fuel Mechanical Model

    SciTech Connect (OSTI)

    Williford, R. E.

    1982-12-01T23:59:59.000Z

    This report describes the results of a series of laboratory experiments conducted to independently verify a model that describes the nonlinear mechanical behavior of cracked fuel in pelletized UO{sub 2}/Zircaloy nuclear fuel rods under normal operating conditions. After a brief description of the analytical model, each experiment is discussed in detail. Experiments were conducted to verify the general behavior and numerical values for the three primary independent modelling parameters (effective crack roughness, effective gap roughness, and total crack length), and to verify the model predictions that the effective Young's moduli for cracked fuel systems were substantially less than those for solid UO{sub 2} pellets. In general, the model parameters and predictions were confirmed, and new insight was gained concerning the complexities of cracked fuel mechanics.

  17. Byrne, et al., 2008. In Peter Droege eds. Urban Energy Transition: From Fossil Fuels to Renewable Power.

    E-Print Network [OSTI]

    Delaware, University of

    Byrne, et al., 2008. In Peter Droege eds. Urban Energy Transition: From Fossil Fuels to Renewable to significantly increase the share of such emissions attributed to Southern countries. Nevertheless, on a per and industrializing countries are derived by assuming the same trend for change in the national shares of emissions

  18. Quantum Plasma Model with Hydrodynamical Phase Transition

    E-Print Network [OSTI]

    Introduction The quantum Jellium model is a system of electrons, interacting via Coulomb forces both with one of Fourier's law of heat conduction for a certain model of interacting atoms, the passage from quantum. The object of the present article is to provide a further quantum mechanical treatment of * Partially

  19. Modeling the Effect of Fuel Ethanol Concentration on Cylinder Pressure Evolution in Direct-Injection Flex-Fuel Engines

    E-Print Network [OSTI]

    Stefanopoulou, Anna

    Modeling the Effect of Fuel Ethanol Concentration on Cylinder Pressure Evolution in Direct the fuel vaporization pro- cess for ethanol-gasoline fuel blends and the associated charge cooling effect from both measured and modeled cylinder pressure exhibit a monotonic correlation with the fuel ethanol

  20. Fuel cycle assessment: A compendium of models, methodologies, and approaches

    SciTech Connect (OSTI)

    Not Available

    1994-07-01T23:59:59.000Z

    The purpose of this document is to profile analytical tools and methods which could be used in a total fuel cycle analysis. The information in this document provides a significant step towards: (1) Characterizing the stages of the fuel cycle. (2) Identifying relevant impacts which can feasibly be evaluated quantitatively or qualitatively. (3) Identifying and reviewing other activities that have been conducted to perform a fuel cycle assessment or some component thereof. (4) Reviewing the successes/deficiencies and opportunities/constraints of previous activities. (5) Identifying methods and modeling techniques/tools that are available, tested and could be used for a fuel cycle assessment.

  1. Model Year 2006: Alternative Fuel and Advanced Technology Vehicles

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

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative1 First Use of Energy for All Purposes (Fuel and Nonfuel), 2002; Level: National5Sales for4,645U.S. DOEThe Bonneville PowerCherries 82981-1cnHighandSWPA / SPRA /Ml'. William Hirst Hirst Enterprises,MODEL

  2. CASL-U-2015-0015-000 Modeling Integral Fuel

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

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative1 First Use of Energy for All Purposes (Fuel and Nonfuel), 2002; Level: National5Sales for4,645U.S. DOE Office511041clothAdvanced Materials Advanced. C o w l i t z C o . C l a r k C o . CL25-000 Modeling Integral

  3. DART's (Dallas Area Rapid Transit) LNG Bus Fleet Start-Up Experience (Alternative Fuel Transit Buses Brochure)

    SciTech Connect (OSTI)

    Battelle

    2000-06-30T23:59:59.000Z

    This report, based on interviews and site visits conducted in October 1999, describes the start-up activities of the DART liquefied natural gas program, identifying problem areas, highlighting successes, and capturing the lessons learned in DART's ongoing efforts to remain at the forefront of the transit industry.

  4. Kinetic Modeling of Combustion Characteristics of Real Biodiesel Fuels

    SciTech Connect (OSTI)

    Naik, C V; Westbrook, C K

    2009-04-08T23:59:59.000Z

    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.

  5. Roadmap for Hydrogen and Fuel Cell Vehicles in California: A Transition Strategy through 2017

    E-Print Network [OSTI]

    Ogden, J; Cunningham, Joshua M; Nicholas, Michael A

    2010-01-01T23:59:59.000Z

    recently re-instated hydrogen and fuel cell vehicle researchTM_2007_094.pdf 6. Hydrogen and Fuel Cell Technical AdvisoryCommittee (HTAC), “Hydrogen and Fuel Cell Technical Advisory

  6. Feasibility and economics of existing PWR transition to a higher power core using annular fuel

    E-Print Network [OSTI]

    Beccherle, Julien

    2007-01-01T23:59:59.000Z

    The internally and externally cooled annular fuel is a new type of fuel for PWRs that enables an increase in core power density by 50% within the same or better safety margins as the traditional solid fuel. Each annular ...

  7. Detailed Chemical Kinetic Modeling of Iso-octane SI-HCCI Transition

    SciTech Connect (OSTI)

    Havstad, Mark A [Lawrence Livermore National Laboratory (LLNL); Aceves, Salvador M [Lawrence Livermore National Laboratory (LLNL); McNenly, Matthew J [Lawrence Livermore National Laboratory (LLNL); Piggott, William T [Lawrence Livermore National Laboratory (LLNL); Edwards, Kevin Dean [ORNL; Wagner, Robert M [ORNL; Daw, C Stuart [ORNL; FINNEY, Charles E A [ORNL

    2010-01-01T23:59:59.000Z

    We describe a CHEMKIN-based multi-zone model that simulates the expected combustion variations in a single-cylinder engine fueled with iso-octane as the engine transitions from spark-ignited (SI) combustion to homogenous charge compression ignition (HCCI) combustion. The model includes a 63-species reaction mechanism and mass and energy balances for the cylinder and the exhaust flow. For this study we assumed that the SI-to-HCCI transition is implemented by means of increasing the internal exhaust gas recirculation (EGR) at constant engine speed. This transition scenario is consistent with that implemented in previously reported experimental measurements on an experimental engine equipped with variable valve actuation. We find that the model captures many of the important experimental trends, including stable SI combustion at low EGR (-0.10), a transition to highly unstable combustion at intermediate EGR, and finally stable HCCI combustion at very high EGR (-0.75). Remaining differences between the predicted and experimental instability patterns indicate that there is further room for model improvement.

  8. DETAILED CHEMICAL KINETIC MODELING OF ISO-OCTANE SI-HCCI TRANSITION

    SciTech Connect (OSTI)

    Havstad, M A; Aceves, S M; McNenly, M J; Piggott, W T; Edwards, K D; Wagner, R M; Daw, C S; Finney, C A

    2009-10-12T23:59:59.000Z

    The authors describe a CHEMKIN-based multi-zone model that simulates the expected combustion variations in a single-cylinder engine fueled with iso-octane as the engine transitions from spark-ignited (ST) combustion to homogeneous charge compression ignition (HCCI) combustion. The model includes a 63-species reaction mechanism and mass and energy balances for the cylinder and the exhaust flow. For this study they assumed that the SI-to-HCCI transition is implemented by means of increasing the internal exhaust gas recirculation (EGR) at constant engine speed. This transition scneario is consistent with that implemented in previously reported experimental measurements on an experimental engine equipped with variable valve actuation. They find that the model captures many of the important experimental trends, including stable SI combustion at low EGR ({approx} 0.10), a transition to highly unstable combustion at intermediate EGR, and finally stable HCCI combustion at very high EGR ({approx} 0.75). Remaining differences between the predicted and experimental instability patterns indicate that there is further room for model improvement.

  9. LG Solid Oxide Fuel Cell (SOFC) Model Development

    SciTech Connect (OSTI)

    Haberman, Ben; Martinez-Baca, Carlos; Rush, Greg

    2013-03-31T23:59:59.000Z

    This report presents a summary of the work performed by LG Fuel Cell Systems Inc. during the project LG Solid Oxide Fuel Cell (SOFC) Model Development (DOE Award Number: DE-FE0000773) which commenced on October 1, 2009 and was completed on March 31, 2013. The aim of this project is for LG Fuel Cell Systems Inc. (formerly known as Rolls-Royce Fuel Cell Systems (US) Inc.) (?LGFCS?) to develop a multi-physics solid oxide fuel cell (SOFC) computer code (MPC) for performance calculations of the LGFCS fuel cell structure to support fuel cell product design and development. A summary of the initial stages of the project is provided which describes the MPC requirements that were developed and the selection of a candidate code, STAR-CCM+ (CD-adapco). This is followed by a detailed description of the subsequent work program including code enhancement and model verification and validation activities. Details of the code enhancements that were implemented to facilitate MPC SOFC simulations are provided along with a description of the models that were built using the MPC and validated against experimental data. The modeling work described in this report represents a level of calculation detail that has not been previously available within LGFCS.

  10. Roadmap for Hydrogen and Fuel Cell Vehicles in California: A Transition Strategy through 2017

    E-Print Network [OSTI]

    Ogden, J; Cunningham, Joshua M; Nicholas, Michael A

    2010-01-01T23:59:59.000Z

    s future commitment to hydrogen and fuel cell vehicles haselimination of the U.S. DOE hydrogen production, deliveryhas recently re-instated hydrogen and fuel cell vehicle

  11. Roadmap for Hydrogen and Fuel Cell Vehicles in California: A Transition Strategy through 2017

    E-Print Network [OSTI]

    Ogden, J; Cunningham, Joshua M; Nicholas, Michael A

    2010-01-01T23:59:59.000Z

    also novel new on-site hydrogen storage systems. In relationfor fuel cells and hydrogen storage), fuel cell durability,firms) on vehicle hydrogen storage pressure and station

  12. A phase transition in commuting Gaussian multi-matrix models

    E-Print Network [OSTI]

    Ofer Aharony; Sean A. Hartnoll

    2007-07-02T23:59:59.000Z

    We analyze in detail a second order phase transition that occurs in large N Gaussian multi-matrix models in which the matrices are constrained to be commuting. The phase transition occurs as the relative masses of the matrices are varied, assuming that there are at least four matrices in the lowest mass level. We also discuss the phase structure of weakly coupled large N 3+1 dimensional gauge theories compactified on a three-sphere of radius R. We argue that these theories are well described at high temperatures (T >> 1/R) by a Gaussian multi-matrix model, and that they do not exhibit any phase transitions between the deconfinement scale (T ~ 1/R) and the scale where perturbation theory breaks down (T ~ 1 / \\lambda R, where \\lambda is the 't Hooft coupling).

  13. Modeling and Optimization of PEMFC Systems and its Application to Direct Hydrogen Fuel Cell Vehicles

    E-Print Network [OSTI]

    Zhao, Hengbing; Burke, Andy

    2008-01-01T23:59:59.000Z

    Polymer Electrolyte Fuel Cell Model, J. Electrochem. Soc. ,in Polymer Electrolyte Fuel Cells, J. Electrochem. Soc. ,Solid-Polymer- Electrolyte Fuel Cell, J. Electrochem. Soc. ,

  14. Modeling and Optimization of PEMFC Systems and its Application to Direct Hydrogen Fuel Cell Vehicles

    E-Print Network [OSTI]

    Zhao, Hengbing; Burke, Andy

    2008-01-01T23:59:59.000Z

    derived from a basic diagnostic fuel cell model [3] was usedExperimental Diagnostics in Polymer Electrolyte Fuel Cells,

  15. Risk Modelling the Transition of SCADA System to IPv6

    E-Print Network [OSTI]

    Boyer, Edmond

    Risk Modelling the Transition of SCADA System to IPv6 Suriadi Suriadi, Alan Tickle, Ejaz Ahmed.morarji@qut.edu.au Abstract. SCADA is one of a set of manufacturing-and-control systems that are used to monitor and control6 protocol and inevitably this change will affect SCADA systems. However IPv6 introduces its own set

  16. Zero-Safe Nets: Modeling Transactions via Transition Synchronization

    E-Print Network [OSTI]

    Bruni, Roberto

    Zero-Safe Nets: Modeling Transactions via Transition Synchronization Roberto Bruni and Ugo of the same zero-safe net. Zero-safe nets (ZS nets) have been introduced in [BM97] to provide a basic called stable places), ZS nets include a set of zero places. These are idealized resources that remain in

  17. Fuel Cell Buses in U.S. Transit Fleets: Current Status 2014

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

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Home Page on Google Bookmark EERE: Alternative Fuels Data Center Home Page on Delicious Rank EERE: Alternative Fuels Data Center Home Page onConversions toE15 and Infrastructure K. MoriartyFuel

  18. Fuel Cell Buses in U.S. Transit Fleets: Current Status 2013

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

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Home Page on Google Bookmark EERE: Alternative Fuels Data Center Home Page on Delicious Rank EERE: Alternative Fuels Data Center Home PageStation LocationsGeneseeValley of theEthanol8 F l e eFuel

  19. Transitioning from Fuel Cells to Redox Flow Cells | Department of Energy

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

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Home Page on Google Bookmark EERE: Alternative Fuels DataDepartment of Energy Your Density Isn'tOriginEducationVideoStrategic|IndustrialCenter Gets People Work,Amy7AUnderstanding |

  20. Models for estimation of car fuel consumption in urban traffic

    SciTech Connect (OSTI)

    Biggs, D.C.; Akcelik

    1986-07-01T23:59:59.000Z

    This article describes four fuel-consumption models. The models are interrelated and form part of the same modeling framework. A simpler model is derived from a more complicated model keeping the vehicle characteristic such as mass, drag function, and energy efficiency as explicit parameters at all model levels. Because vehicle characteristics are likely to change over time and from country to country, this is a particularly useful model property. For simplicity here, only the instantaneous fuel-consumption model is described in any detail. However, because of the derivation procedure, many of the features and properties of this model are present in the more aggregate models. Easy-to-use functions and graphs are given for the more aggregate models based on a ''default car'' in urban driving conditions. All parameters related to the speed profile and driving environment were calibrated using on-road data collected in Sydney, Australia. Use of the models is illustrated by estimating the fuel consumption for the microtrip.

  1. Phase Transition of Laminated Models at Any Temperature

    E-Print Network [OSTI]

    Eugene Pechersky; Elena Petrova; Sergey Pirogov

    2010-02-18T23:59:59.000Z

    The standard Pirogov -- Sinai theory is generalized to the class of models with two modes of interaction: longitudinal and transversal. Under rather general assumptions about the longitudinal interaction and for one specific form of the transversal interaction it is proved that such system has a variety of phase transitions at any temperature: the parameter which plays the role of inverse temperature is the strength of the transversal interaction. The concrete examples of such systems are $(1+1)$-dimensional models.

  2. Software Platform Evaluation - Verifiable Fuel Cycle Simulation (VISION) Model

    SciTech Connect (OSTI)

    J. J. Jacobson; D. E. Shropshire; W. B. West

    2005-11-01T23:59:59.000Z

    The purpose of this Software Platform Evaluation (SPE) is to document the top-level evaluation of potential software platforms on which to construct a simulation model that satisfies the requirements for a Verifiable Fuel Cycle Simulation Model (VISION) of the Advanced Fuel Cycle (AFC). See the Software Requirements Specification for Verifiable Fuel Cycle Simulation (VISION) Model (INEEL/EXT-05-02643, Rev. 0) for a discussion of the objective and scope of the VISION model. VISION is intended to serve as a broad systems analysis and study tool applicable to work conducted as part of the AFCI (including costs estimates) and Generation IV reactor development studies. This document will serve as a guide for selecting the most appropriate software platform for VISION. This is a “living document” that will be modified over the course of the execution of this work.

  3. Calibration of a fuel relocation model in BISON

    SciTech Connect (OSTI)

    Swiler, L. P. [Optimization and Uncertainty, Quantification Dept., Sandia National Laboratories, Albuquerque, NM 87185-1318 (United States); Williamson, R. L.; Perez, D. M. [Fuels Modeling and Simulation Dept., Idaho National Laboratory, Idaho Falls, ID 83415 (United States)

    2013-07-01T23:59:59.000Z

    We demonstrate parameter calibration in the context of the BISON nuclear fuels performance analysis code. Specifically, we present the calibration of a parameter governing fuel relocation: the power level at which the relocation model is activated. This relocation activation parameter is a critical value in obtaining reasonable comparison with fuel centerline temperature measurements. It also is the subject of some debate in terms of the optimal values. We show that the optimal value does vary across the calibration to individual rods. We also demonstrate an aggregated calibration, where we calibrate to observations from six rods. (authors)

  4. Fuel Cell Buses in U.S. Transit Fleets: Current Status 2012 | Department of

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

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Home Page on Google Bookmark EERE: Alternative Fuels DataDepartment of Energy Your Density Isn't YourTransport inEnergy0.pdfTechnologies Program (FCTP) (Fact Sheet) |Energy 12 Fuel Cell

  5. Hydrogen and Fuel Cell Transit Bus Evaluations: Joint Evaluation Plan for

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

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Home Page on Google Bookmark EERE: Alternative Fuels DataDepartment of Energy Your Density Isn't YourTransport(Fact Sheet), GeothermalGridHYDROGEND D eReviewEducation » ForFuelHydrogenthe U.S.

  6. Hydrogen and Fuel Cell Transit Bus Evaluations: Joint Evaluation Plan for

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

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Home Page on Google Bookmark EERE: Alternative Fuels DataDepartment of Energy Your Density Isn't YourTransport(Fact Sheet), GeothermalGridHYDROGEND D eReviewEducation » ForFuelHydrogenthe

  7. Alternative Liquid Fuels Simulation Model (AltSim).

    SciTech Connect (OSTI)

    Baker, Arnold Barry; Williams, Ryan (Hobart and William Smith Colleges, Geneva, NY); Drennen, Thomas E.; Klotz, Richard (Hobart and William Smith Colleges, Geneva, NY)

    2007-10-01T23:59:59.000Z

    The Alternative Liquid Fuels Simulation Model (AltSim) is a high-level dynamic simulation model which calculates and compares the production costs, carbon dioxide emissions, and energy balances of several alternative liquid transportation fuels. These fuels include: corn ethanol, cellulosic ethanol, biodiesel, and diesels derived from natural gas (gas to liquid, or GTL) and coal (coal to liquid, or CTL). AltSim allows for comprehensive sensitivity analyses on capital costs, operation and maintenance costs, renewable and fossil fuel feedstock costs, feedstock conversion efficiency, financial assumptions, tax credits, CO{sub 2} taxes, and plant capacity factor. This paper summarizes the preliminary results from the model. For the base cases, CTL and cellulosic ethanol are the least cost fuel options, at $1.60 and $1.71 per gallon, respectively. Base case assumptions do not include tax or other credits. This compares to a $2.35/gallon production cost of gasoline at September, 2007 crude oil prices ($80.57/barrel). On an energy content basis, the CTL is the low cost alternative, at $12.90/MMBtu, compared to $22.47/MMBtu for cellulosic ethanol. In terms of carbon dioxide emissions, a typical vehicle fueled with cellulosic ethanol will release 0.48 tons CO{sub 2} per year, compared to 13.23 tons per year for coal to liquid.

  8. Mechanism of oxygen reduction reaction on transition metal oxide catalysts for high temperature fuel cells

    E-Print Network [OSTI]

    La O', Gerardo Jose Cordova

    2008-01-01T23:59:59.000Z

    The solid oxide fuel cell (SOFC) with its high energy conversion efficiency, low emissions, silent operation and its ability to utilize commercial fuels has the potential to create a large impact on the energy landscape. ...

  9. Fuel Cell Buses in U.S. Transit Fleets: Summary of Experiences and Current Status

    SciTech Connect (OSTI)

    Eudy, L.; Chandler, K.; Gikakis, C.

    2007-09-01T23:59:59.000Z

    This report reviews past and present fuel cell bus technology development and implementation in the United States.

  10. Heat transfer modeling of dry spent nuclear fuel storage facilities

    SciTech Connect (OSTI)

    Lee, S.Y.

    1999-07-01T23:59:59.000Z

    The present work was undertaken to provide heat transfer model that accurately predicts the thermal performance of dry spent nuclear fuel storage facilities. One of the storage configurations being considered for DOE Aluminum-clad Spent Nuclear Fuel (Al-SNF), such as the Material and Testing Reactor (MTR) fuel, is in a dry storage facility. To support design studies of storage options a computational and experimental program has been conducted at the Savannah River Site (SRS). The main objective is to develop heat transfer models including natural convection effects internal to an interim dry storage canister and to geologic codisposal Waste Package (WP). Calculated temperatures will be used to demonstrate engineering viability of a dry storage option in enclosed interim storage and geologic repository WP and to assess the chemical and physical behaviors of the Al-SNF in the dry storage facilities. The current paper describes the modeling approaches and presents the computational results along with the experimental data.

  11. Heat Transfer Modeling of Dry Spent Nuclear Fuel Storage Facilities

    SciTech Connect (OSTI)

    Lee, S.Y.

    1999-01-13T23:59:59.000Z

    The present work was undertaken to provide heat transfer model that accurately predicts the thermal performance of dry spent nuclear fuel storage facilities. One of the storage configurations being considered for DOE Aluminum-clad Spent Nuclear Fuel (Al-SNF), such as the Material and Testing Reactor (MTR) fuel, is in a dry storage facility. To support design studies of storage options a computational and experimental program has been conducted at the Savannah River Site (SRS). The main objective is to develop heat transfer models including natural convection effects internal to an interim dry storage canister and to geological codisposal Waste Package (WP). Calculated temperatures will be used to demonstrate engineering viability of a dry storage option in enclosed interim storage and geological repository WP and to assess the chemical and physical behaviors of the Al-SNF in the dry storage facilities. The current paper describes the modeling approaches and presents the computational results along with the experimental data.

  12. Modeling of Spent Fuel Oxidation at Low Temperature

    SciTech Connect (OSTI)

    Poulesquen, Arnaud; Ferry, Cecile [Department of Physico Chemistry, CEA, Gif sur Yvette, 91191 (France); Desgranges, Lionel [Department of Spent Fuel Studies, CEA, St Paul lez Durance, 13108 (France)

    2007-07-01T23:59:59.000Z

    During dry storage, the oxidation of the spent fuel in case of cladding and container failure (accidental scenario) could be detrimental for further handling of the spent fuel rod and for the safety of the facilities. Depending on whether the uranium dioxide is under the form of powder or pellet, irradiated or unirradiated, the weight gain curves do not present the same shape. To account for these different behaviours, two models have been developed. Firstly, the oxidation of unirradiated powders has been modelled based on the coexistence, during the oxidation, of two intermediate products, U{sub 4}O{sub 9} and U{sub 3}O{sub 7}. The comparison between the calculation and the literature data is good in terms of weight gain curves and chemical diffusion coefficient of oxygen within the two phases. Secondly, the oxidation of spent fuel fragments is approached by a convolution procedure between a grain oxidation model and an empirical parameter which represents the linear oxidation speed of grain boundary or an average distance able to cover the entire spent fuel fragment. This procedure of calculation allows in one hand to account for the incubation period noticed on unirradiated pellets or spent fuel and in another hand to link the empirical parameter to physical as porosity, cracks or linear power, or operational parameters such as fission gas release (FGR) respectively. A comparison of this new modelling with experimental data will be proposed. (authors)

  13. VISION -- A Dynamic Model of the Nuclear Fuel Cycle

    SciTech Connect (OSTI)

    J. J. Jacobson; A. M. Yacout; S. J. Piet; D. E. Shropshire; G. E. Matthern

    2006-02-01T23:59:59.000Z

    The Advanced Fuel Cycle Initiative’s (AFCI) fundamental objective is to provide technology options that – if implemented – would enable long-term growth of nuclear power while improving sustainability and energy security. The AFCI organization structure consists of four areas; Systems Analysis, Fuels, Separations and Transmutations. The Systems Analysis Working Group is tasked with bridging the program technical areas and providing the models, tools, and analyses required to assess the feasibility of design and deploy¬ment options and inform key decision makers. An integral part of the Systems Analysis tool set is the development of a system level model that can be used to examine the implications of the different mixes of reactors, implications of fuel reprocessing, impact of deployment technologies, as well as potential “exit” or “off ramp” approaches to phase out technologies, waste management issues and long-term repository needs. The Verifiable Fuel Cycle Simulation Model (VISION) is a computer-based simulation model that allows performing dynamic simulations of fuel cycles to quantify infrastructure requirements and identify key trade-offs between alternatives. VISION is intended to serve as a broad systems analysis and study tool applicable to work conducted as part of the AFCI (including costs estimates) and Generation IV reactor development studies.

  14. The FIT Model - Fuel-cycle Integration and Tradeoffs

    SciTech Connect (OSTI)

    Steven J. Piet; Nick R. Soelberg; Samuel E. Bays; Candido Pereira; Layne F. Pincock; Eric L. Shaber; Meliisa C Teague; Gregory M Teske; Kurt G Vedros

    2010-09-01T23:59:59.000Z

    All mass streams from fuel separation and fabrication are products that must meet some set of product criteria – fuel feedstock impurity limits, waste acceptance criteria (WAC), material storage (if any), or recycle material purity requirements such as zirconium for cladding or lanthanides for industrial use. These must be considered in a systematic and comprehensive way. The FIT model and the “system losses study” team that developed it [Shropshire2009, Piet2010] are an initial step by the FCR&D program toward a global analysis that accounts for the requirements and capabilities of each component, as well as major material flows within an integrated fuel cycle. This will help the program identify near-term R&D needs and set longer-term goals. The question originally posed to the “system losses study” was the cost of separation, fuel fabrication, waste management, etc. versus the separation efficiency. In other words, are the costs associated with marginal reductions in separations losses (or improvements in product recovery) justified by the gains in the performance of other systems? We have learned that that is the wrong question. The right question is: how does one adjust the compositions and quantities of all mass streams, given uncertain product criteria, to balance competing objectives including cost? FIT is a method to analyze different fuel cycles using common bases to determine how chemical performance changes in one part of a fuel cycle (say used fuel cooling times or separation efficiencies) affect other parts of the fuel cycle. FIT estimates impurities in fuel and waste via a rough estimate of physics and mass balance for a set of technologies. If feasibility is an issue for a set, as it is for “minimum fuel treatment” approaches such as melt refining and AIROX, it can help to make an estimate of how performances would have to change to achieve feasibility.

  15. Fuel Cell Buses in U.S. Transit Fleets: Current Status 2009 | Department of

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

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Home Page on Google Bookmark EERE: Alternative Fuels DataDepartment of Energy Your Density Isn't YourTransport inEnergy0.pdfTechnologies Program (FCTP) (Fact Sheet) |

  16. Fact #555: January 26, 2009 Transit Buses are Relying Less on Diesel Fuel |

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

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Home Page on Google Bookmark EERE: Alternative Fuels DataDepartment of Energy Your Density Isn't YourTransport in RepresentativeDepartment of Energy Score Maturityof Energy

  17. Fuel Conditioning Facility Electrorefiner Model Predictions versus Measurements

    SciTech Connect (OSTI)

    D Vaden

    2007-10-01T23:59:59.000Z

    Electrometallurgical treatment of spent nuclear fuel is performed in the Fuel Conditioning Facility (FCF) at the Idaho National Laboratory (INL) by electrochemically separating uranium from the fission products and structural materials in a vessel called an electrorefiner (ER). To continue processing without waiting for sample analyses to assess process conditions, an ER process model predicts the composition of the ER inventory and effluent streams via multicomponent, multi-phase chemical equilibrium for chemical reactions and a numerical solution to differential equations for electro-chemical transport. The results of the process model were compared to the electrorefiner measured data.

  18. TRISO Fuel Performance: Modeling, Integration into Mainstream Design Studies, and Application to a Thorium-fueled Fusion-Fission Hybrid Blanket

    E-Print Network [OSTI]

    Powers, Jeffrey

    2011-01-01T23:59:59.000Z

    Quantification in Fuel Performance Modeling . . . . . . .3.4 Integration with Fuel Performance Calculations ivmicroscopic image of a TRISO fuel particle cracked open to

  19. Fuel Performance Experiments and Modeling: Fission Gas Bubble Nucleation and Growth in Alloy Nuclear Fuels

    SciTech Connect (OSTI)

    McDeavitt, Sean; Shao, Lin; Tsvetkov, Pavel; Wirth, Brian; Kennedy, Rory

    2014-04-07T23:59:59.000Z

    Advanced fast reactor systems being developed under the DOE's Advanced Fuel Cycle Initiative are designed to destroy TRU isotopes generated in existing and future nuclear energy systems. Over the past 40 years, multiple experiments and demonstrations have been completed using U-Zr, U-Pu-Zr, U-Mo and other metal alloys. As a result, multiple empirical and semi-empirical relationships have been established to develop empirical performance modeling codes. many mechamistic questions about fission as mobility, bubble coalescience, and gas release have been answered through industrial experience, reearch, and empirical understanding. The advent of modern computational materials science, however, opens new doors of development such that physics-based multi-scale models may be developed to enable a new generation of predictive fuel performance codes that are not limited by empiricism.

  20. Virginia Tech Comprehensive Power-based Fuel Consumption Model: Model Development and Testing

    E-Print Network [OSTI]

    Rakha, Hesham A.

    The transportation sector consumes approximately 30% of the total energy in the United States, which is mostlyVirginia Tech Comprehensive Power-based Fuel Consumption Model: Model Development and Testing, Moran, Saerens, and Van den Bulck 2 ABSTRACT Existing fuel consumption and emission models suffer from

  1. Roadmap for Hydrogen and Fuel Cell Vehicles in California: A Transition Strategy through 2017

    E-Print Network [OSTI]

    Ogden, J; Cunningham, Joshua M; Nicholas, Michael A

    2010-01-01T23:59:59.000Z

    diagnostics Supplier Development analysis predecessor Service, Aftersales Years Figure 7: Automotive lead times for production vehicle programs (Contributions from Automotive Fuel Cell

  2. Fuel Cell Buses in U.S. Transit Fleets: Summary of Experiences and Current

    Energy Savers [EERE]

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Home Page onYou are now leaving Energy.gov You are now leaving Energy.gov You are being directed offOCHCO2: FinalOffers3.pdf0-45.pdf0 Budget Fossil Energy FYWednesday, December 03,Status |

  3. A Global Market in Transition: Local Markets in Jeopardy NASEO-EIA Summer Fuels Conference

    Gasoline and Diesel Fuel Update (EIA)

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative1 First Use of Energy for All Purposes (Fuel and Nonfuel), 2002; Level: National5Sales for On-Highway4,1,50022,3,,,,6,1,9,1,50022,3,,,,6,1,Decade Year-0E (2001)gasoline prices4 Oil Electricity

  4. Washington Metropolitan Area Transit Authority: Biodiesel Fuel Comparison Final Data Report

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

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative1 First Use of Energy for All Purposes (Fuel and Nonfuel), 2002; Level:Energy: Grid Integration Redefining What'sis Taking Over OurThe Iron SpinPrincetonUsing Maps1DOE AwardsD ContractBOE Reserve

  5. A Model Fuels Consortium to Promote Engine Modeling | Department of Energy

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

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Home Page on Google Bookmark EERE: Alternative Fuels DataDepartment of Energy Your Density Isn't Your Destiny: The Future of BadTHEEnergyReliability2015GrossA FewA LIMITEDA|A Model Fuels

  6. Stochastic storage models and noise-induced phase transitions

    E-Print Network [OSTI]

    Serge Shpyrko; V. V. Ryazanov

    2007-01-13T23:59:59.000Z

    The most frequently used in physical application diffusive (based on the Fokker-Planck equation) model leans upon the assumption of small jumps of a macroscopic variable for each given realization of the stochastic process. This imposes restrictions on the description of the phase transition problem where the system is to overcome some finite potential barrier, or systems with finite size where the fluctuations are comparable with the size of a system. We suggest a complementary stochastic description of physical systems based on the mathematical stochastic storage model with basic notions of random input and output into a system. It reproduces statistical distributions typical for noise-induced phase transitions (e.g. Verhulst model) for the simplest (up to linear) forms of the escape function. We consider a generalization of the stochastic model based on the series development of the kinetic potential. On the contrast to Gaussian processes in which the development in series over a small parameter characterizing the jump value is assumed [Stratonovich R.L., Nonlinear Nonequilibrium Thermodynamics, Springer Series in Synergetics, vol.59, Springer Verlag, 1994], we propose a series expansion directly suitable for storage models and introduce the kinetic potential generalizing them.

  7. Fuel Cell Power Model for CHP and CHHP Economics and Performance Analysis (Presentation)

    SciTech Connect (OSTI)

    Steward, D.; Penev, M.

    2010-03-30T23:59:59.000Z

    This presentation describes the fuel cell power model for CHP and CHHP economics and performance analysis.

  8. Hydrogen Scenario Analysis Summary Report: Analysis of the Transition to Hydrogen Fuel Cell Vehicles and the Potential Hydrogen Energy Infrastructure Requirements

    SciTech Connect (OSTI)

    Greene, David L [ORNL; Leiby, Paul Newsome [ORNL; James, Brian [Directed Technologies, Inc.; Perez, Julie [Directed Technologies, Inc.; Melendez, Margo [National Renewable Energy Laboratory (NREL); Milbrandt, Anelia [National Renewable Energy Laboratory (NREL); Unnasch, Stefan [Life Cycle Associates; Rutherford, Daniel [TIAX, LLC; Hooks, Matthew [TIAX, LLC

    2008-03-01T23:59:59.000Z

    Achieving a successful transition to hydrogen-powered vehicles in the U.S. automotive market will require strong and sustained commitment by hydrogen producers, vehicle manufacturers, transporters and retailers, consumers, and governments. The interaction of these agents in the marketplace will determine the real costs and benefits of early market transformation policies, and ultimately the success of the transition itself. The transition to hydrogen-powered transportation faces imposing economic barriers. The challenges include developing and refining a new and different power-train technology, building a supporting fuel infrastructure, creating a market for new and unfamiliar vehicles, and achieving economies of scale in vehicle production while providing an attractive selection of vehicle makes and models for car-buyers. The upfront costs will be high and could persist for a decade or more, delaying profitability until an adequate number of vehicles can be produced and moved into consumer markets. However, the potential rewards to the economy, environment, and national security are immense. Such a profound market transformation will require careful planning and strong, consistent policy incentives. Section 811 of the Energy Policy Act (EPACT) of 2005, Public Law 109-59 (U.S. House, 2005), calls for a report from the Secretary of Energy on measures to support the transition to a hydrogen economy. The report was to specifically address production and deployment of hydrogen-fueled vehicles and the hydrogen production and delivery infrastructure needed to support those vehicles. In addition, the 2004 report of the National Academy of Sciences (NAS, 2004), The Hydrogen Economy, contained two recommendations for analyses to be conducted by the U.S. Department of Energy (DOE) to strengthen hydrogen energy transition and infrastructure planning for the hydrogen economy. In response to the EPACT requirement and NAS recommendations, DOE's Hydrogen, Fuel Cells and Infrastructure Technologies Program (HFCIT) has supported a series of analyses to evaluate alternative scenarios for deployment of millions of hydrogen fueled vehicles and supporting infrastructure. To ensure that these alternative market penetration scenarios took into consideration the thinking of the automobile manufacturers, energy companies, industrial hydrogen suppliers, and others from the private sector, DOE held several stakeholder meetings to explain the analyses, describe the models, and solicit comments about the methods, assumptions, and preliminary results (U.S. DOE, 2006a). The first stakeholder meeting was held on January 26, 2006, to solicit guidance during the initial phases of the analysis; this was followed by a second meeting on August 9-10, 2006, to review the preliminary results. A third and final meeting was held on January 31, 2007, to discuss the final analysis results. More than 60 hydrogen energy experts from industry, government, national laboratories, and universities attended these meetings and provided their comments to help guide DOE's analysis. The final scenarios attempt to reflect the collective judgment of the participants in these meetings. However, they should not be interpreted as having been explicitly endorsed by DOE or any of the stakeholders participating. The DOE analysis examined three vehicle penetration scenarios: Scenario 1--Production of thousands of vehicles per year by 2015 and hundreds of thousands per year by 2019. This option is expected to lead to a market penetration of 2.0 million fuel cell vehicles (FCV) by 2025. Scenario 2--Production of thousands of FCVs by 2013 and hundreds of thousands by 2018. This option is expected to lead to a market penetration of 5.0 million FCVs by 2025. Scenario 3--Production of thousands of FCVs by 2013, hundreds of thousands by 2018, and millions by 2021 such that market penetration is 10 million by 2025. Scenario 3 was formulated to comply with the NAS recommendation: 'DOE should map out and evaluate a transition plan consistent with developing the infrastructure and hydrogen res

  9. Nuclear Energy R&D Imperative 3: Enable a Transition Away from Fossil Fuel in the Transportation and Industrial Sectors

    SciTech Connect (OSTI)

    David Petti; J. Stephen Herring

    2010-03-01T23:59:59.000Z

    As described in the Department of Energy Office of Nuclear Energy’s Nuclear Energy R&D Roadmap, nuclear energy can play a significant role in supplying energy for a growing economy while reducing both our dependence on foreign energy supplies and emissions from the burning of fossil fuels. The industrial and transportation sectors are responsible for more than half of the greenhouse gas emissions in the U.S., and imported oil supplies 70% of the energy used in the transportation sector. It is therefore important to examine the various ways nuclear energy can facilitate a transition away from fossil fuels to secure environmentally sustainable production and use of energy in the transportation and manufacturing industry sectors. Imperative 3 of the Nuclear Energy R&D Roadmap, entitled “Enable a Transition Away from Fossil Fuels by Producing Process Heat for use in the Transportation and Industrial Sectors”, addresses this need. This document presents an Implementation Plan for R&D efforts related to this imperative. The expanded use of nuclear energy beyond the electrical grid will contribute significantly to overcoming the three inter-linked energy challenges facing U.S. industry: the rising and volatile prices for premium fossil fuels such as oil and natural gas, dependence on foreign sources for these fuels, and the risks of climate change resulting from carbon emissions. Nuclear energy could be used in the industrial and transportation sectors to: • Generate high temperature process heat and electricity to serve industrial needs including the production of chemical feedstocks for use in manufacturing premium fuels and fertilizer products, • Produce hydrogen for industrial processes and transportation fuels, and • Provide clean water for human consumption by desalination and promote wastewater treatment using low-grade nuclear heat as a useful additional benefit. Opening new avenues for nuclear energy will significantly enhance our nation’s energy security through more effective utilization of our country’s resources while simultaneously providing economic stability and growth (through predictable energy prices and high value jobs), in an environmentally sustainable and secure manner (through lower land and water use, and decreased byproduct emissions). The reduction in imported oil will also increase the retention of wealth within the U.S. economy while still supporting economic growth. Nuclear energy is the only non-fossil fuel that has been demonstrated to reliably supply energy for a growing industrial economy.

  10. TRISO-Fuel Element Performance Modeling for the Hybrid LIFE Engine with Pu Fuel Blanket

    SciTech Connect (OSTI)

    DeMange, P; Marian, J; Caro, M; Caro, A

    2010-02-18T23:59:59.000Z

    A TRISO-coated fuel thermo-mechanical performance study is performed for the hybrid LIFE engine to test the viability of TRISO particles to achieve ultra-high burnup of a weapons-grade Pu blanket. Our methodology includes full elastic anisotropy, time and temperature varying material properties for all TRISO layers, and a procedure to remap the elastic solutions in order to achieve fast fluences up to 30 x 10{sup 25} n {center_dot} m{sup -2} (E > 0.18 MeV). In order to model fast fluences in the range of {approx} 7 {approx} 30 x 10{sup 25} n {center_dot} m{sup -2}, for which no data exist, careful scalings and extrapolations of the known TRISO material properties are carried out under a number of potential scenarios. A number of findings can be extracted from our study. First, failure of the internal pyrolytic carbon (PyC) layer occurs within the first two months of operation. Then, the particles behave as BISO-coated particles, with the internal pressure being withstood directly by the SiC layer. Later, after 1.6 years, the remaining PyC crumbles due to void swelling and the fuel particle becomes a single-SiC-layer particle. Unrestrained by the PyC layers, and at the temperatures and fluences in the LIFE engine, the SiC layer maintains reasonably-low tensile stresses until the end-of-life. Second, the PyC creep constant, K, has a striking influence on the fuel performance of TRISO-coated particles, whose stresses scale almost inversely proportional to K. Obtaining more reliable measurements, especially at higher fluences, is an imperative for the fidelity of our models. Finally, varying the geometry of the TRISO-coated fuel particles results in little differences in the scope of fuel performance. The mechanical integrity of 2-cm graphite pebbles that act as fuel matrix has also been studied and it is concluded that they can reliable serve the entire LIFE burnup cycle without failure.

  11. Fuel Cell Buses in U.S. Transit Fleets: Current Status 2012

    Fuel Cell Technologies Publication and Product Library (EERE)

    This report is the sixth in an annual series of reports that summarize the progress of fuel cell electric bus (FCEB) development in the United States and discuss the achievements and challenges of int

  12. Roadmap for Hydrogen and Fuel Cell Vehicles in California: A Transition Strategy through 2017

    E-Print Network [OSTI]

    Ogden, J; Cunningham, Joshua M; Nicholas, Michael A

    2010-01-01T23:59:59.000Z

    new partnerships? H2-FCV Roadmap Report - FINAL December 21,Roadmap for Hydrogen and Fuel Cell Vehicles in California: ACalifornia, Davis H2-FCV Roadmap Report - FINAL December 21,

  13. Fuel

    SciTech Connect (OSTI)

    NONE

    1999-10-01T23:59:59.000Z

    Two subjects are covered in this section. They are: (1) Health effects of possible contamination at Paducah Gaseous Diffusion Plant to be studied; and (2) DOE agrees on test of MOX fuel in Canada.

  14. A stochastic model dissects cell states in biological transition processes

    E-Print Network [OSTI]

    Armond, Jonathan W.

    Many biological processes, including differentiation, reprogramming, and disease transformations, involve transitions of cells through distinct states. Direct, unbiased investigation of cell states and their transitions ...

  15. Hysteretic transitions in the Kuramoto model with inertia

    E-Print Network [OSTI]

    Simona Olmi; Adrian Navas; Stefano Boccaletti; Alessandro Torcini

    2014-08-11T23:59:59.000Z

    We report finite size numerical investigations and mean field analysis of a Kuramoto model with inertia for fully coupled and diluted systems. In particular, we examine for a Gaussian distribution of the frequencies the transition from incoherence to coherence for increasingly large system size and inertia. For sufficiently large inertia the transition is hysteretic and within the hysteretic region clusters of locked oscillators of various sizes and different levels of synchronization coexist. A modification of the mean field theory developed by Tanaka, Lichtenberg, and Oishi [Physica D, 100 (1997) 279] allows to derive the synchronization profile associated to each of these clusters. We have also investigated numerically the limits of existence of the coherent and of the incoherent solutions. The minimal coupling required to observe the coherent state is largely independent of the system size and it saturates to a constant value already for moderately large inertia values. The incoherent state is observable up to a critical coupling whose value saturates for large inertia and for finite system sizes, while in the thermodinamic limit this critical value diverges proportionally to the mass. By increasing the inertia the transition becomes more complex, and the synchronization occurs via the emergence of clusters of whirling oscillators. The presence of these groups of coherently drifting oscillators induces oscillations in the order parameter. We have shown that the transition remains hysteretic even for randomly diluted networks up to a level of connectivity corresponding to few links per oscillator. Finally, an application to the Italian high-voltage power grid is reported, which reveals the emergence of quasi-periodic oscillations in the order parameter due to the simultaneous presence of many competing whirling clusters.

  16. An improved model for the transit entropy of monatomic liquids

    SciTech Connect (OSTI)

    Wallace, Duane C [Los Alamos National Laboratory; Chisolm, Eric D [Los Alamos National Laboratory; Bock, Nicolas [Los Alamos National Laboratory

    2009-01-01T23:59:59.000Z

    In the original formulation of V-T theory for monatomic liquid dynamics, the transit contribution to entropy was taken to be a universal constant, calibrated to the constant-volume entropy of melting. This model suffers two deficiencies: (a) it does not account for experimental entropy differences of {+-}2% among elemental liquids, and (b) it implies a value of zero for the transit contribution to internal energy. The purpose of this paper is to correct these deficiencies. To this end, the V-T equation for entropy is fitted to an overall accuracy of {+-}0.1% to the available experimental high temperature entropy data for elemental liquids. The theory contains two nuclear motion contributions: (a) the dominant vibrational contribution S{sub vib}(T/{theta}{sub 0}), where T is temperature and {theta}{sub 0} is the vibrational characteristic temperature, and (b) the transit contribution S{sub tr}(T/{theta}{sub tr}), where {theta}{sub tr} is a scaling temperature for each liquid. The appearance of a common functional form of S{sub tr} for all the liquids studied is a property of the experimental data, when analyzed via the V-T formula. The resulting S{sub tr} implies the correct transit contribution to internal energy. The theoretical entropy of melting is derived, in a single formula applying to normal and anomalous melting alike. An ab initio calculation of {theta}{sub 0}, based on density functional theory, is reported for liquid Na and Cu. Comparison of these calculations with the above analysis of experimental entropy data provides verification of V-T theory. In view of the present results, techniques currently being applied in ab initio simulations of liquid properties can be employed to advantage in the further testing and development of V-T theory.

  17. On a Pioneering Polymer Electrolyte Fuel Cell Model

    SciTech Connect (OSTI)

    Weber, Adam Z.; Meyers, Jeremy P.

    2010-07-07T23:59:59.000Z

    "Polymer Electrolyte Fuel Cell Model" is a seminal work that continues to form the basis for modern modeling efforts, especially models concerning the membrane and its behavior at the continuum level. The paper is complete with experimental data, modeling equations, model validation, and optimization scenarios. While the treatment of the underlying phenomena is limited to isothermal, single-phase conditions, and one-dimensional flow, it represents the key interactions within the membrane at the center of the PEFC. It focuses on analyzing the water balance within the cell and clearly demonstrates the complex interactions of water diffusion and electro-osmotic flux. Cell-level and system-level water balance are key to the development of efficient PEFCs going forward, particularly as researchers address the need to simplify humidification and recycle configurations while increasing the operating temperature of the stack to minimize radiator requirements.

  18. MA3T Model Application at ORNL Assesses the Future of Fuel Cell...

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

    Leveraging funding from the Fuel Cell Technologies Office, Oak Ridge National Lab (ORNL) has developed a model for simulating the market potential of fuel cell electric vehicles...

  19. Modeling and Control of High-Velocity Oxygen-Fuel (HVOF) Thermal Spray: A Tutorial Review

    E-Print Network [OSTI]

    Li, Mingheng; Christofides, Panagiotis D.

    2009-01-01T23:59:59.000Z

    Fluid Dynamics Analysis of a Wire- Feed, High-Velocity Oxygen Fuel (Fluid Dynamic Modeling of Gas Flow Charac- teristics in a High-Velocity Oxy-Fuel

  20. Modeling Cold Start in a Polymer-Electrolyte Fuel Cell

    E-Print Network [OSTI]

    Balliet, Ryan

    2010-01-01T23:59:59.000Z

    conditions used for fuel—cell simulations. 3.12 Values usedin Polymer Electrolyte Fuel Cells — II. Parametric Study,”of Polymer Electrolyte Fuel Cells,” Electrochimica Acta, 53,

  1. Radionuclide release rates from spent fuel for performance assessment modeling

    SciTech Connect (OSTI)

    Curtis, D.B.

    1994-11-01T23:59:59.000Z

    In a scenario of aqueous transport from a high-level radioactive waste repository, the concentration of radionuclides in water in contact with the waste constitutes the source term for transport models, and as such represents a fundamental component of all performance assessment models. Many laboratory experiments have been done to characterize release rates and understand processes influencing radionuclide release rates from irradiated nuclear fuel. Natural analogues of these waste forms have been studied to obtain information regarding the long-term stability of potential waste forms in complex natural systems. This information from diverse sources must be brought together to develop and defend methods used to define source terms for performance assessment models. In this manuscript examples of measures of radionuclide release rates from spent nuclear fuel or analogues of nuclear fuel are presented. Each example represents a very different approach to obtaining a numerical measure and each has its limitations. There is no way to obtain an unambiguous measure of this or any parameter used in performance assessment codes for evaluating the effects of processes operative over many millennia. The examples are intended to suggest by example that in the absence of the ability to evaluate accuracy and precision, consistency of a broadly based set of data can be used as circumstantial evidence to defend the choice of parameters used in performance assessments.

  2. Enabling Advanced Modeling and Simulations for Fuel-Flexible Combustors

    SciTech Connect (OSTI)

    Pitsch, Heinz

    2010-05-31T23:59:59.000Z

    The overall goal of the present project is to enable advanced modeling and simulations for the design and optimization of fuel-flexible turbine combustors. For this purpose we use a high fidelity, extensively-tested large-eddy simulation (LES) code and state-of-the-art models for premixed/partially-premixed turbulent combustion developed in the PI's group. In the frame of the present project, these techniques are applied, assessed, and improved for hydrogen enriched premixed and partially premixed gas-turbine combustion. Our innovative approaches include a completely consistent description of flame propagation; a coupled progress variable/level set method to resolve the detailed flame structure, and incorporation of thermal-diffusion (non-unity Lewis number) effects. In addition, we have developed a general flamelet-type transformation holding in the limits of both non-premixed and premixed burning. As a result, a model for partially premixed combustion has been derived. The coupled progress variable/level method and the general flamelet transformation were validated by LES of a lean-premixed low-swirl burner that has been studied experimentally at Lawrence Berkeley National Laboratory. The model is extended to include the non-unity Lewis number effects, which play a critical role in fuel-flexible combustor with high hydrogen content fuel. More specifically, a two-scalar model for lean hydrogen and hydrogen-enriched combustion is developed and validated against experimental and direct numerical simulation (DNS) data. Results are presented to emphasize the importance of non-unity Lewis number effects in the lean-premixed low-swirl burner of interest in this project. The proposed model gives improved results, which shows that the inclusion of the non-unity Lewis number effects is essential for accurate prediction of the lean-premixed low-swirl flame.

  3. Adaptive Planning for Markov Decision Processes with Uncertain Transition Models via Incremental Feature Dependency Discovery

    E-Print Network [OSTI]

    Geramifard, Alborz

    Solving large scale sequential decision making problems without prior knowledge of the state transition model is a key problem in the planning literature. One approach to tackle this problem is to learn the state transition ...

  4. Lattice spacing dependence of phase transition temperature in the classical linear sigma model

    E-Print Network [OSTI]

    A. K. Chaudhuri

    2001-05-02T23:59:59.000Z

    We have investigated the phase transition properties of classical linear sigma model. The fields were kept in contact with a heat bath for sufficiently long time such that fields are equilibrated at the temperature of the heat bath. It was shown that the sigma model fields undergoes phase transition, but the transition temperature depend crucially on the lattice spacing. In the continuum limit, the transition temperature tends to zero or at least to a very low value.

  5. THERMODYNAMIC MODEL FOR URANIUM DIOXIDE BASED NUCLEAR FUEL

    SciTech Connect (OSTI)

    Thompson, Dr. William T. [Royal Military College of Canada; Lewis, Dr. Brian J [Royal Military College of Canada; Corcoran, E. C. [Royal Military College of Canada; Kaye, Dr. Matthew H. [Royal Military College of Canada; White, S. J. [Royal Military College of Canada; Akbari, F. [Atomic Energy of Canada Limited, Chalk River Laboratories; Higgs, Jamie D. [Atomic Energy of Canada Limited, Point Lepreau; Thompson, D. M. [Praxair Inc.; Besmann, Theodore M [ORNL; Vogel, S. C. [Los Alamos National Laboratory (LANL)

    2007-01-01T23:59:59.000Z

    Many projects involving nuclear fuel rest on a quantitative understanding of the co-existing phases at various stages of burnup. Since the many fission products have considerably different abilities to chemically associate with oxygen, and the oxygen-to-metal molar ratio is slowly changing, the chemical potential of oxygen is a function of burnup. Concurrently, well-recognized small fractions of new phases such as inert gas, noble metals, zirconates, etc. also develop. To further complicate matters, the dominant UO2 fuel phase may be non-stoichiometric and most of the minor phases themselves have a variable composition dependent on temperature and possible contact with the coolant in the event of a sheathing breach. A thermodynamic fuel model to predict the phases in partially burned CANDU (CANada Deuterium Uranium) nuclear fuel containing many major fission products has been under development. The building blocks of the model are the standard Gibbs energies of formation of the many possible compounds expressed as a function of temperature. To these data are added mixing terms associated with the appearance of the component species in particular phases. In operational terms, the treatment rests on the ability to minimize the Gibbs energy in a multicomponent system, in our case using the algorithms developed by Eriksson. The model is capable of handling non-stoichiometry in the UO2 fluorite phase, dilute solution behaviour of significant solute oxides, noble metal inclusions, a second metal solid solution U(Pd-Rh-Ru)3, zirconate, molybdate, and uranate solutions as well as other minor solid phases, and volatile gaseous species.

  6. Heavy Duty Diesel Particulate Matter and Fuel Consumption Modeling for Transportation Analysis

    E-Print Network [OSTI]

    Scora, George Alexander

    2011-01-01T23:59:59.000Z

    measured second-by-second fuel use. Mesoscale Modeling DataSet and Mesoscale ModelCalibration Mesoscale model calibration and validation

  7. HCCI experiments with gasoline surrogate fuels modeled by a semidetailed chemical kinetic model

    SciTech Connect (OSTI)

    Andrae, J.C.G. [Dept. of Chemical Engineering and Technology, Royal Institute of Technology (KTH), SE-100 44 Stockholm (Sweden); Head, R.A. [Shell Technology Centre Thornton, P.O. Box 1, Chester CH1 3SH (United Kingdom)

    2009-04-15T23:59:59.000Z

    Experiments in a homogeneous charge compression ignition (HCCI) engine have been conducted with four gasoline surrogate fuel blends. The pure components in the surrogate fuels consisted of n-heptane, isooctane, toluene, ethanol and diisobutylene and fuel sensitivities (RON-MON) in the fuel blends ranged from two to nine. The operating conditions for the engine were p{sub in}=0.1 and 0.2 MPa, T{sub in}=80 and 250 C, {phi}=0.25 in air and engine speed 1200 rpm. A semidetailed chemical kinetic model (142 species and 672 reactions) for gasoline surrogate fuels, validated against ignition data from experiments conducted in shock tubes for gasoline surrogate fuel blends at 1.0{<=} p{<=}5.0MPa, 700{<=} T{<=}1200 K and {phi}=1.0, was successfully used to qualitatively predict the HCCI experiments using a single zone modeling approach. The fuel blends that had higher fuel sensitivity were more resistant to autoignition for low intake temperature and high intake pressure and less resistant to autoignition for high intake temperature and low intake pressure. A sensitivity analysis shows that at high intake temperature the chemistry of the fuels ethanol, toluene and diisobutylene helps to advance ignition. This is consistent with the trend that fuels with the least Negative Temperature Coefficient (NTC) behavior show the highest octane sensitivity, and become less resistant to autoignition at high intake temperatures. For high intake pressure the sensitivity analysis shows that fuels in the fuel blend with no NTC behavior consume OH radicals and acts as a radical scavenger for the fuels with NTC behavior. This is consistent with the observed trend of an increase in RON and fuel sensitivity. With data from shock tube experiments in the literature and HCCI modeling in this work, a correlation between the reciprocal pressure exponent on the ignition delay to the fuel sensitivity and volume percentage of single-stage ignition fuel in the fuel blend was found. Higher fuel sensitivity and single-stage fuel content generally gives a lower value of the pressure exponent. This helps to explain the results obtained while boosting the intake pressure in the HCCI engine. (author)

  8. Development and validation of a transition model based on a mechanical approximation

    E-Print Network [OSTI]

    Vizinho, R; Silvestre, M

    2015-01-01T23:59:59.000Z

    A new 3D transition turbulence model, more accurate and faster than an empirical transition model, is proposed. The model is based on the calculation of the pre-transitional u'v' due to mean flow shear. The present transition model is fully described and verified against eight benchmark test cases. Computations are performed for the ERCOFTAC flat-plate T3A, T3C and T3L test cases. Further, the model is validated for bypass, cross-flow and separation induced transition and compared with empirical transition models. The model presents very good results for bypass transition under zero-pressure gradient and with pressure gradient flow conditions. Also the model is able to correctly predict separation induced transition. However, for very low speed and low free-stream turbulence intensity the model delays separation induced transition onset. The model also shows very good results for transition under complex cross-flow conditions in three-dimensional geometries. The 3D tested case was the 6:1 prolate-spheroid und...

  9. Modeling water content effects in polymer electrolyte fuel cells

    SciTech Connect (OSTI)

    Springer, T.E.; Zawodzinski, T.A.; Gottesfeld, S.

    1991-01-01T23:59:59.000Z

    Water content and transport is the key factor in the one-dimensional, steady-state model of a complete polymer electrolyte fuel cell (PEFC) described here. Water diffusion coefficients, electroosmotic drag coefficients, water sorption isotherms, and membrane conductivities, all measured in our laboratory as functions of membrane water content, were used in the model. The model predicts a net-water-per-proton flux ratio of 0.2 H{sub 2}O/H{sup +} under typical operating conditions, which is much less than the measured electroosmotic drag coefficient for a fully hydrated membrane. It also predicts an increase in membrane resistance with increased current density and demonstrates the great advantage of thinner membranes in alleviating this resistance problem. Both of these predictions were verified experimentally under certain conditions. We also describe the sensitivity of the water concentration profile and associated observables to variations in the values of some of the transport parameters in anticipation of applying the model to fuel cells employing other membranes. 16 refs., 9 figs.

  10. Technical Breakthrough Points and Opportunities in Transition Scenarios for Hydrogen as Vehicular Fuel

    SciTech Connect (OSTI)

    Diakov, V.; Ruth, M.; James, B.; Perez, J.; Spisak, A.

    2011-12-01T23:59:59.000Z

    This technical reports is about investigating a generic case of hydrogen production/delivery/dispensing pathway evolution in a large population city, assuming that hydrogen fuel cell electric vehicles (FCEV) will capture a major share of the vehicle market by the year 2050. The range of questions that are considered includes (i) what is the typical succession of hydrogen pathways that minimizes consumer cost? (ii) what are the major factors that will likely influence this sequence?

  11. MATHEMATICAL MODELING OF CHANNEL POROUS LAYER INTERFACES IN PEM FUEL CELLS

    E-Print Network [OSTI]

    Ehrhardt, Matthias

    MATHEMATICAL MODELING OF CHANNEL ­ POROUS LAYER INTERFACES IN PEM FUEL CELLS M. EHRHARDT, J, Germany ABSTRACT In proton exchange membrane (PEM) fuel cells, the transport of the fuel to the active diffusion layers. In order to improve existing mathematical and numerical models of PEM fuel cells, a deeper

  12. Helium Behavior in Oxide Nuclear Fuels: First Principles Modeling

    SciTech Connect (OSTI)

    D. Gryaznov; S. Rashkeev; E. A. Kotomin; E. Heifets; Y. Zhukovskii

    2010-10-01T23:59:59.000Z

    UO2 and (U, Pu)O2 solid solutions (the so-called MOX) nowadays are used as commercial nuclear fuels in many countries. One of the safety issues during the storage of these fuels is related to their self-irradiation that produces and accumulates point defects and helium therein. We present density functional theory (DFT) calculations for UO2, PuO2 and MOX containing He atoms in octahedral interstitial positions. In particular, we calculated basic MOX properties and He incorporation energies as functions of Pu concentration within the spin-polarized, generalized gradient approximation (GGA) DFT calculations. We also included the on-site electron correlation corrections using the Hubbard model (in the framework of the so-called DFT + U approach). We found that PuO2 remains semiconducting with He in the octahedral position while UO2 requires a specific lattice distortion. Both materials reveal a positive energy for He incorporation, which, therefore, is an exothermic process. The He incorporation energy increases with the Pu concentration in the MOX fuel.

  13. Model documentation Renewable Fuels Module of the National Energy Modeling System

    SciTech Connect (OSTI)

    NONE

    1996-01-01T23:59:59.000Z

    This report documents the objectives, analaytical approach and design of the National Energy Modeling System (NEMS) Renewable Fuels Module (RFM) as it relates to the production of the 1996 Annual Energy Outlook forecasts. The report catalogues and describes modeling assumptions, computational methodologies, data inputs, and parameter estimation techniques. A number of offline analyses used in lieu of RFM modeling components are also described.

  14. Integrating repositories with fuel cycles: The airport authority model

    SciTech Connect (OSTI)

    Forsberg, C. [Massachusetts Inst. of Technology, 77 Massachusetts Avenue, Cambridge, MA 02139-4307 (United States)

    2012-07-01T23:59:59.000Z

    The organization of the fuel cycle is a legacy of World War II and the cold war. Fuel cycle facilities were developed and deployed without consideration of the waste management implications. This led to the fuel cycle model of a geological repository site with a single owner, a single function (disposal), and no other facilities on site. Recent studies indicate large economic, safety, repository performance, nonproliferation, and institutional incentives to collocate and integrate all back-end facilities. Site functions could include geological disposal of spent nuclear fuel (SNF) with the option for future retrievability, disposal of other wastes, reprocessing with fuel fabrication, radioisotope production, other facilities that generate significant radioactive wastes, SNF inspection (navy and commercial), and related services such as SNF safeguards equipment testing and training. This implies a site with multiple facilities with different owners sharing some facilities and using common facilities - the repository and SNF receiving. This requires a different repository site institutional structure. We propose development of repository site authorities modeled after airport authorities. Airport authorities manage airports with government-owned runways, collocated or shared public and private airline terminals, commercial and federal military facilities, aircraft maintenance bases, and related operations - all enabled and benefiting the high-value runway asset and access to it via taxi ways. With a repository site authority the high value asset is the repository. The SNF and HLW receiving and storage facilities (equivalent to the airport terminal) serve the repository, any future reprocessing plants, and others with needs for access to SNF and other wastes. Non-public special-built roadways and on-site rail lines (equivalent to taxi ways) connect facilities. Airport authorities are typically chartered by state governments and managed by commissions with members appointed by the state governor, county governments, and city governments. This structure (1) enables state and local governments to work together to maximize job and tax benefits to local communities and the state, (2) provides a mechanism to address local concerns such as airport noise, and (3) creates an institutional structure with large incentives to maximize the value of the common asset, the runway. A repository site authority would have a similar structure and be the local interface to any national waste management authority. (authors)

  15. Dynamics of the Oil Transition: Modeling Capacity, Costs, and Emissions

    E-Print Network [OSTI]

    Brandt, Adam R.; Farrell, Alexander E.

    2008-01-01T23:59:59.000Z

    crude oil availabil- ity has the following results: less overall fuel consumption,crude-oil-equivalent fuels), the “emissions penalty” (in gigatonnes of carbon equivalent), and the total emissions from fuel production and consumption (

  16. CONTROL-ORIENTED MODELING OF A SOLID-OXIDE FUEL CELL STACK USING AN LPV MODEL STRUCTURE

    E-Print Network [OSTI]

    Sanandaji, Borhan M.

    CONTROL-ORIENTED MODELING OF A SOLID-OXIDE FUEL CELL STACK USING AN LPV MODEL STRUCTURE Borhan M dynamic model of a solid oxide fuel cell stack. Using a detailed physical model as a starting point, we (usually air) on the cathode side. Solid-oxide fuel cells (SOFCs) utilize a ceramic oxygen-ion conducting

  17. Sensitivity of economic performance of the nuclear fuel cycle to simulation modeling assumptions

    E-Print Network [OSTI]

    Bonnet, Nicéphore

    2007-01-01T23:59:59.000Z

    Comparing different nuclear fuel cycles and assessing their implications require a fuel cycle simulation model as complete and realistic as possible. In this thesis, methodological implications of modeling choices are ...

  18. Object Tracking and Multimedia Augmented Transition Network for Video Indexing and Modeling

    E-Print Network [OSTI]

    Chen, Shu-Ching

    Object Tracking and Multimedia Augmented Transition Network for Video Indexing and Modeling Shu, IN 47907 kashyap@ecn.purdue.edu Abstract In our previous work, a multimedia augmented transition network (ATN) model together with its multimedia input strings were proposed to model and structure video data

  19. Emissions characterization of two methanol-fueled transit buses. Final report, April-September 1985

    SciTech Connect (OSTI)

    Ullman, T.L.; Hare, C.T.

    1986-02-01T23:59:59.000Z

    Exhaust emissions from the two methanol-powered buses used in the California Methanol Bus Demonstration have been characterized. The M.A.N. SU 240 bus is powered by M.A.N.'s D2566 FMUH methanol engine, and utilizes catalytic exhaust aftertreatment. The GMC RTS II 04 bus is powered by a first-generation DDAD 6V-92TA methanol engine without exhaust aftertreatment. Emissions of HC, CO, NO, unburned methanol, aldehydes, total particulates, and soluble fraction of particulate were determined for both buses over steady-state and transient chassis dynamometer test cycles. Emission levels from the M.A.N. bus were considerably lower than those from the GMC bus, with the exception of NO. Comparison of emission levels from methanol- and diesel-powered buses indicates that substantial reduction in emissions (especially particulate and NO) are possible with careful implementation of methanol fueling.

  20. Computer Modeling Illuminates Degradation Pathways of Cations in Alkaline Membrane Fuel Cells (Fact Sheet)

    SciTech Connect (OSTI)

    Not Available

    2012-08-01T23:59:59.000Z

    Cation degradation insights obtained by computational modeling could result in better performance and longer lifetime for alkaline membrane fuel cells.

  1. MODELING THE PERFORMANCE OF HIGH BURNUP THORIA AND URANIA PWR FUEL

    E-Print Network [OSTI]

    Long, Y.

    Fuel performance models have been developed to assess the performance of ThO[subscript 2]-UO[subscript 2]

  2. Fuel-Cycle Analysis of Hydrogen-Powered Fuel-Cell Systems with the GREET Model

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

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Home Page on Google Bookmark EERE: Alternative Fuels DataDepartment of Energy Your Density Isn't YourTransport inEnergy0.pdfTechnologies ProgramOutfitted with SCR | Department

  3. Hydrogen and Fuel Cell Transit Bus Evaluations: Joint Evaluation Plan for the U.S. Department of Energy and the Federal Transit Administration (Report and Appendix)

    SciTech Connect (OSTI)

    Eudy, L.; Chandler, K.

    2008-05-01T23:59:59.000Z

    This document describes the hydrogen transit bus evaluations performed by the National Renewable Energy Laboratory (NREL) and funded by the U.S. Department of Energy (DOE) and the U.S. Department of Transportation's Federal Transit Administration (FTA).

  4. Alternative Liquid Fuels Simulation Model (AltSim).

    SciTech Connect (OSTI)

    Williams, Ryan; Baker, Arnold Barry; Drennen, Thomas E.

    2009-12-01T23:59:59.000Z

    The Alternative Liquid Fuels Simulation Model (AltSim) is a high-level dynamic simulation model which calculates and compares the production and end use costs, greenhouse gas emissions, and energy balances of several alternative liquid transportation fuels. These fuels include: corn ethanol, cellulosic ethanol from various feedstocks (switchgrass, corn stover, forest residue, and farmed trees), biodiesel, and diesels derived from natural gas (gas to liquid, or GTL), coal (coal to liquid, or CTL), and coal with biomass (CBTL). AltSim allows for comprehensive sensitivity analyses on capital costs, operation and maintenance costs, renewable and fossil fuel feedstock costs, feedstock conversion ratio, financial assumptions, tax credits, CO{sub 2} taxes, and plant capacity factor. This paper summarizes the structure and methodology of AltSim, presents results, and provides a detailed sensitivity analysis. The Energy Independence and Security Act (EISA) of 2007 sets a goal for the increased use of biofuels in the U.S., ultimately reaching 36 billion gallons by 2022. AltSim's base case assumes EPA projected feedstock costs in 2022 (EPA, 2009). For the base case assumptions, AltSim estimates per gallon production costs for the five ethanol feedstocks (corn, switchgrass, corn stover, forest residue, and farmed trees) of $1.86, $2.32, $2.45, $1.52, and $1.91, respectively. The projected production cost of biodiesel is $1.81/gallon. The estimates for CTL without biomass range from $1.36 to $2.22. With biomass, the estimated costs increase, ranging from $2.19 per gallon for the CTL option with 8% biomass to $2.79 per gallon for the CTL option with 30% biomass and carbon capture and sequestration. AltSim compares the greenhouse gas emissions (GHG) associated with both the production and consumption of the various fuels. EISA allows fuels emitting 20% less greenhouse gases (GHG) than conventional gasoline and diesels to qualify as renewable fuels. This allows several of the CBTL options to be included under the EISA mandate. The estimated GHG emissions associated with the production of gasoline and diesel are 19.80 and 18.40 kg of CO{sub 2} equivalent per MMBtu (kgCO{sub 2}e/MMBtu), respectively (NETL, 2008). The estimated emissions are significantly higher for several alternatives: ethanol from corn (70.6), GTL (51.9), and CTL without biomass or sequestration (123-161). Projected emissions for several other alternatives are lower; integrating biomass and sequestration in the CTL processes can even result in negative net emissions. For example, CTL with 30% biomass and 91.5% sequestration has estimated production emissions of -38 kgCO{sub 2}e/MMBtu. AltSim also estimates the projected well-to-wheel, or lifecycle, emissions from consuming each of the various fuels. Vehicles fueled with conventional diesel or gasoline and driven 12,500 miles per year emit 5.72-5.93 tons of CO{sub 2} equivalents per year (tCO{sub 2}e/yr). Those emissions are significantly higher for vehicles fueled with 100% ethanol from corn (8.03 tCO{sub 2}e/yr) or diesel from CTL without sequestration (10.86 to 12.85 tCO{sub 2}/yr). Emissions could be significantly lower for vehicles fueled with diesel from CBTL with various shares of biomass. For example, for CTL with 30% biomass and carbon sequestration, emissions would be 2.21 tCO{sub 2}e per year, or just 39% of the emissions for a vehicle fueled with conventional diesel. While the results presented above provide very specific estimates for each option, AltSim's true potential is as a tool for educating policy makers and for exploring 'what if?' type questions. For example, AltSim allows one to consider the affect of various levels of carbon taxes on the production cost estimates, as well as increased costs to the end user on an annual basis. Other sections of AltSim allow the user to understand the implications of various polices in terms of costs to the government or land use requirements. AltSim's structure allows the end user to explore each of these alternatives and understand the sensitivities implications a

  5. MicroScale Modeling of an AnodeSupported Planar Solid Oxide Fuel Cell

    E-Print Network [OSTI]

    Paris-Sud XI, Université de

    1 Micro­Scale Modeling of an Anode­Supported Planar Solid Oxide Fuel Cell P. Chinda1 , W. Wechsatol A micro ­ scale model of a Solid Oxide Fuel Cell (SOFC) involving the mass transfer together the available literatures. Keywords: Solid Oxide Fuel Cells, Micro ­ Scale Model, Mass Transfer, Electrochemical

  6. Capacity planning in a transitional economy: What issues? Which models?

    SciTech Connect (OSTI)

    Mubayi, V.; Leigh, R.W. [Brookhaven National Lab., Upton, NY (United States); Bright, R.N. [Anylec Research, Inc., Bayport, NY (United States)

    1996-03-01T23:59:59.000Z

    This paper is devoted to an exploration of the important issues facing the Russian power generation system and its evolution in the foreseeable future and the kinds of modeling approaches that capture those issues. These issues include, for example, (1) trade-offs between investments in upgrading and refurbishment of existing thermal (fossil-fired) capacity and safety enhancements in existing nuclear capacity versus investment in new capacity, (2) trade-offs between investment in completing unfinished (under construction) projects based on their original design versus investment in new capacity with improved design, (3) incorporation of demand-side management options (investments in enhancing end-use efficiency, for example) within the planning framework, (4) consideration of the spatial dimensions of system planning including investments in upgrading electric transmission networks or fuel shipment networks and incorporating hydroelectric generation, (5) incorporation of environmental constraints and (6) assessment of uncertainty and evaluation of downside risk. Models for exploring these issues include low power shutdown (LPS) which are computationally very efficient, though approximate, and can be used to perform extensive sensitivity analyses to more complex models which can provide more detailed answers but are computationally cumbersome and can only deal with limited issues. The paper discusses which models can usefully treat a wide range of issues within the priorities facing decision makers in the Russian power sector and integrate the results with investment decisions in the wider economy.

  7. Comparison of bifurcation dynamics of turbulent transport models for the L-H transition

    SciTech Connect (OSTI)

    Weymiens, W., E-mail: w.weymiens@differ.nl; Blank, H. J. de; Hogeweij, G. M. D. [FOM Institute DIFFER—Dutch Institute for Fundamental Energy Research, Association EURATOM-FOM, PO Box 1207, Nieuwegein (Netherlands)] [FOM Institute DIFFER—Dutch Institute for Fundamental Energy Research, Association EURATOM-FOM, PO Box 1207, Nieuwegein (Netherlands); Paquay, S. [Department of Applied Physics, Eindhoven University of Technology, PO Box 503, Eindhoven (Netherlands)] [Department of Applied Physics, Eindhoven University of Technology, PO Box 503, Eindhoven (Netherlands)

    2014-05-15T23:59:59.000Z

    In more than three decades, a large amount of models and mechanisms have been proposed to describe a very beneficial feature of magnetically confined fusion plasmas: the L-H transition. Bifurcation theory can be used to compare these different models based on their dynamical transition structure. In this paper, we employ bifurcation theory to distinguish two fundamentally different descriptions of the interaction between turbulence levels and sheared flows. The analytic bifurcation analysis characterises the parameter space structure of the transition dynamics. Herewith, in these models three dynamically different types of transitions are characterised, sharp transitions, oscillatory transitions, and smooth transitions. One of the two models has a very robust transition structure and is therefore likely to be more accurate for such a robust phenomenon as the L-H transition. The other model needs more fine-tuning to get non-oscillatory transitions. These conclusions from the analytic bifurcation analysis are confirmed by dedicated numerical simulations, with the newly developed code Bifurcator.

  8. The quantum Biroli-Mézard model: glass transition and superfluidity in a quantum lattice glass model

    E-Print Network [OSTI]

    Laura Foini; Guilhem Semerjian; Francesco Zamponi

    2011-03-12T23:59:59.000Z

    We study the quantum version of a lattice model whose classical counterpart captures the physics of structural glasses. We discuss the role of quantum fluctuations in such systems and in particular their interplay with the amorphous order developed in the glass phase. We show that quantum fluctuations might facilitate the formation of the glass at low enough temperature. We also show that the glass transition becomes a first-order transition between a superfluid and an insulating glass at very low temperature, and is therefore accompanied by phase coexistence between superfluid and glassy regions.

  9. Advanced Fuel Performance: Modeling and Simulation Light Water Reactor Fuel Performance:

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

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative1 First Use of Energy for All Purposes (Fuel and Nonfuel), 2002; Level: National5Sales for4,645U.S. DOE Office511041cloth DocumentationProducts (VAP) VAP7-0973 1BP-14 Power andAdvanced ComponentsenzymeAdvanced Fossil

  10. HCCI experiments with toluene reference fuels modeled by a semidetailed chemical kinetic model

    SciTech Connect (OSTI)

    Andrae, J.C.G. [Department of Chemical Engineering and Technology, Royal Institute of Technology (KTH), SE-100 44 Stockholm (Sweden); Brinck, T. [Department of Physical Chemistry, Royal Institute of Technology (KTH), SE-100 44 Stockholm (Sweden); Kalghatgi, G.T. [Shell Global Solutions (UK), P.O. Box 1, Chester CH1 3SH (United Kingdom)

    2008-12-15T23:59:59.000Z

    A semidetailed mechanism (137 species and 633 reactions) and new experiments in a homogeneous charge compression ignition (HCCI) engine on the autoignition of toluene reference fuels are presented. Skeletal mechanisms for isooctane and n-heptane were added to a detailed toluene submechanism. The model shows generally good agreement with ignition delay times measured in a shock tube and a rapid compression machine and is sensitive to changes in temperature, pressure, and mixture strength. The addition of reactions involving the formation and destruction of benzylperoxide radical was crucial to modeling toluene shock tube data. Laminar burning velocities for benzene and toluene were well predicted by the model after some revision of the high-temperature chemistry. Moreover, laminar burning velocities of a real gasoline at 353 and 500 K could be predicted by the model using a toluene reference fuel as a surrogate. The model also captures the experimentally observed differences in combustion phasing of toluene/n-heptane mixtures, compared to a primary reference fuel of the same research octane number, in HCCI engines as the intake pressure and temperature are changed. For high intake pressures and low intake temperatures, a sensitivity analysis at the moment of maximum heat release rate shows that the consumption of phenoxy radicals is rate-limiting when a toluene/n-heptane fuel is used, which makes this fuel more resistant to autoignition than the primary reference fuel. Typical CPU times encountered in zero-dimensional calculations were on the order of seconds and minutes in laminar flame speed calculations. Cross reactions between benzylperoxy radicals and n-heptane improved the model predictions of shock tube experiments for {phi}=1.0 and temperatures lower than 800 K for an n-heptane/toluene fuel mixture, but cross reactions had no influence on HCCI simulations. (author)

  11. Adaptive Model Predictive Control of the Hybrid Dynamics of a Fuel Cell System.

    E-Print Network [OSTI]

    Paris-Sud XI, Université de

    Adaptive Model Predictive Control of the Hybrid Dynamics of a Fuel Cell System. M. Fiacchini, T operation of a fuel cell system is presented. The aim of the control design is to guarantee that the oxygen control to a fuel cell plant is presented. The fuel cell, located in the laboratory of the Department

  12. Recent advances in single-chamber fuel-cells: Experiment and modeling , Zongping Shao b

    E-Print Network [OSTI]

    Haile, Sossina M.

    Recent advances in single-chamber fuel-cells: Experiment and modeling Yong Hao a , Zongping Shao b; accepted 6 May 2006 Abstract Single-chamber fuel cells (SCFC) are ones in which the fuel and oxidizer is discussed. © 2006 Elsevier B.V. All rights reserved. Keywords: Solid oxide fuel cell; Single chamber

  13. Bifurcation analysis and dimension reduction of a predator-prey model for the L-H transition

    SciTech Connect (OSTI)

    Dam, Magnus; Brøns, Morten [Department of Applied Mathematics and Computer Science, Technical University of Denmark, DK-2800 Kgs. Lyngby (Denmark)] [Department of Applied Mathematics and Computer Science, Technical University of Denmark, DK-2800 Kgs. Lyngby (Denmark); Juul Rasmussen, Jens; Naulin, Volker [Association Euratom-DTU, Department of Physics, Technical University of Denmark, DTU Risø Campus, DK-4000 Roskilde (Denmark)] [Association Euratom-DTU, Department of Physics, Technical University of Denmark, DTU Risø Campus, DK-4000 Roskilde (Denmark); Xu, Guosheng [Institute of Plasma Physics, Chinese Academy of Sciences, Hefei 230031 (China)] [Institute of Plasma Physics, Chinese Academy of Sciences, Hefei 230031 (China)

    2013-10-15T23:59:59.000Z

    The L-H transition denotes a shift to an improved confinement state of a toroidal plasma in a fusion reactor. A model of the L-H transition is required to simulate the time dependence of tokamak discharges that include the L-H transition. A 3-ODE predator-prey type model of the L-H transition is investigated with bifurcation theory of dynamical systems. The analysis shows that the model contains three types of transitions: an oscillating transition, a sharp transition with hysteresis, and a smooth transition. The model is recognized as a slow-fast system. A reduced 2-ODE model consisting of the full model restricted to the flow on the critical manifold is found to contain all the same dynamics as the full model. This means that all the dynamics in the system is essentially 2-dimensional, and a minimal model of the L-H transition could be a 2-ODE model.

  14. Chemical Kinetic Modeling of Fuels | Department of Energy

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

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Home Page on Google Bookmark EERE: Alternative Fuels DataDepartment of Energy Your Density Isn't Your Destiny: Theof EnergyAdministration-DesertofSuccessTroy A. Semelsberger LosFuels

  15. CONTROL-ORIENTED MODEL OF AN INTEGRATED FUEL CELL STACK AND FUEL

    E-Print Network [OSTI]

    Stefanopoulou, Anna

    -based principles. The fuel processor converts a hydrocarbon fuel to a hydrogen (H2) rich mixture that is directly and responsiveness to load changes (Dicks, 1996), but delivers lower conversion efficiency. The main reactor) reactor. Here, hydrogen-rich gas is produced by mixing natural gas with air over a catalyst bed

  16. Dynamics of the Oil Transition: Modeling Capacity, Costs, and Emissions

    E-Print Network [OSTI]

    Brandt, Adam R.; Farrell, Alexander E.

    2008-01-01T23:59:59.000Z

    manufactured in two steps: a syngas comprised mainly of COfeedstock, then the syngas is converted into liquid fuel

  17. Modeling Cold Start in a Polymer-Electrolyte Fuel Cell

    E-Print Network [OSTI]

    Balliet, Ryan

    2010-01-01T23:59:59.000Z

    Boundary conditions used for fuel—cell simulations. 3.12to the Problem of Cold Start 1.1 Polymer—Electrolyte Fuelin Polymer Electrolyte Fuel Cells — II. Parametric Study,”

  18. A non-isothermal PEM fuel cell model including two water transport mechanisms in the

    E-Print Network [OSTI]

    Münster, Westfälische Wilhelms-Universität

    A non-isothermal PEM fuel cell model including two water transport mechanisms in the membrane K Freiburg Germany A dynamic two-phase flow model for proton exchange mem- brane (PEM) fuel cells and the species concentrations. In order to describe the charge transport in the fuel cell the Poisson equations

  19. Liquid Water Dynamics in a Model Polymer Electrolyte Fuel Cell Flow Channel

    E-Print Network [OSTI]

    Victoria, University of

    Liquid Water Dynamics in a Model Polymer Electrolyte Fuel Cell Flow Channel by Chris Miller in a Model Polymer Electrolyte Fuel Cell Flow Channel by Chris Miller Bachelors of Engineering, University in a polymer electrolyte fuel cell is a critical issue in ensuring high cell performance. The water production

  20. P0906-090-Chnani Macroscopic Model of Solid Oxide Fuel Cell Stack for

    E-Print Network [OSTI]

    Paris-Sud XI, Université de

    1 P0906-090-Chnani Macroscopic Model of Solid Oxide Fuel Cell Stack for Integrating in a Generator fuel cell (SOFC) with the aim to perform a simulation of the whole generator. Three sub-models have at the catalytic sites and gas flows at fuel cell input and output. The electrical response is based

  1. A Planar Anode -Supported Solid Oxide Fuel Cell Model with Internal Reforming of Natural Gas

    E-Print Network [OSTI]

    Boyer, Edmond

    1 A Planar Anode - Supported Solid Oxide Fuel Cell Model with Internal Reforming of Natural Gas.brault@univ-orleans.fr Abstract Solid Oxide Fuel Cells (SOFCs) are of great interest due to their high energy efficiency, low, a mathematical model of a co - flow planar anode - supported solid oxide fuel cell with internal reforming

  2. Experimental Study of Water Droplet Flows in a Model PEM Fuel Cell Gas Microchannel

    E-Print Network [OSTI]

    Victoria, University of

    Experimental Study of Water Droplet Flows in a Model PEM Fuel Cell Gas Microchannel by Grant Minor Experimental Study of Water Droplet Flows in a Model PEM Fuel Cell Gas Microchannel by Grant Minor B. Eng. Mgmt Committee Member, Mechanical Engineering). Abstract Liquid water formation and flooding in PEM fuel cell gas

  3. A Three-Dimensional Computational Model of PEM Fuel Cell with Serpentine Gas Channels

    E-Print Network [OSTI]

    Victoria, University of

    A Three-Dimensional Computational Model of PEM Fuel Cell with Serpentine Gas Channels by Phong) fuel cell with serpentine gas flow channels is presented in this thesis. This comprehensive model accounts for important transport phenomena in a fuel cell such as heat transfer, mass transfer, electrode

  4. Agent-Based Modeling and Simulation for Hydrogen Transition Analysis

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

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Home Page on Google Bookmark EERE: Alternative Fuels DataDepartment of Energy Your Density Isn't Your Destiny: The Future of1Albuquerque, NM - Building America TopAgendaLaboratory is managed by

  5. HyPro: Modeling the Hydrogen Transition | Department of Energy

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

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Home Page on Google Bookmark EERE: Alternative Fuels DataDepartment of Energy Your Density Isn't YourTransport(Fact Sheet), GeothermalGridHYDROGEND D e e pShade Your HomeofEnergy?AnalysisHyPro:

  6. High Performance Ceramic Interconnect Material for Solid Oxide Fuel Cells (SOFCs): Ca- and Transition Metal-doped Yttrium Chromite

    SciTech Connect (OSTI)

    Yoon, Kyung J.; Stevenson, Jeffry W.; Marina, Olga A.

    2011-10-15T23:59:59.000Z

    The effect of transition metal substitution on thermal and electrical properties of Ca-doped yttrium chromite was investigated in relation to use as a ceramic interconnect in high temperature solid oxide fuel cells (SOFCs). 10 at% Co, 4 at% Ni, and 1 at% Cu substitution on B-site of 20 at% Ca-doped yttrium chromite led to a close match of thermal expansion coefficient (TEC) with that of 8 mol% yttria-stabilized zirconia (YSZ), and a single phase Y0.8Ca0.2Cr0.85Co0.1Ni0.04Cu0.01O3 remained stable between 25 and 1100 degree C over a wide oxygen partial pressure range. Doping with Cu significantly facilitated densification of yttrium chromite. Ni dopant improved both electrical conductivity and dimensional stability in reducing environments, likely through diminishing the oxygen vacancy formation. Substitution with Co substantially enhanced electrical conductivity in oxidizing atmosphere, which was attributed to an increase in charge carrier density and hopping mobility. Electrical conductivity of Y0.8Ca0.2Cr0.85Co0.1Ni0.04Cu0.01O3 at 900 degree C is 57 S/cm in air and 11 S/cm in fuel (pO2=5×10^-17 atm) environments. Chemical compatibility of doped yttrium chromite with other cell components was verified at the processing temperatures. Based on the chemical and dimensional stability, sinterability, and thermal and electrical properties, Y0.8Ca0.2Cr0.85Co0.1Ni0.04Cu0.01O3 is suggested as a promising SOFC ceramic interconnect to potentially overcome technical limitations of conventional acceptor-doped lanthanum chromites.

  7. Connecticut Fuel Cell Activities: Markets, Programs, and Models |

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

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Home Page on Google Bookmark EERE: Alternative Fuels Data Center Home Page onYouTube YouTube Note: Since the YouTube platformBuildingCoalComplex Flow WorkshopInformationData Dashboard

  8. Connecticut Fuel Cell Activities: Markets, Programs, and Models

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

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Home Page on Google Bookmark EERE: Alternative Fuels DataDepartment of Energy Your Density Isn't Your Destiny: Theof"Wave the WhiteNational|ofSeptemberConfrontingFY 2011 FY 2011Connecticut

  9. Water Transport in PEM Fuel Cells: Advanced Modeling, Material Selection,

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

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Home Page on Google Bookmark EERE: Alternative Fuels DataDepartment of Energy Your DensityEnergy U.S.-China Electric Vehicle and03/02ReportWaste-to-Energy andApril 10,Department ofTesting

  10. Water Transport in PEM Fuel Cells: Advanced Modeling, Material Selection,

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

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Home Page on Google Bookmark EERE: Alternative Fuels DataDepartment of Energy Your DensityEnergy U.S.-China Electric Vehicle and03/02ReportWaste-to-Energy andApril 10,Department

  11. Advancement in Fuel Spray and Combustion Modeling for Compression Ignition

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

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Home Page on Google Bookmark EERE: Alternative Fuels DataDepartment of Energy Your Density Isn't Your Destiny: The Future of1 AAcceleratedDepartmentDepartment2 DOE HydrogenAdvanced,

  12. Renewable Fuel Vehicle Modeling and Analysis | Department of Energy

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

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Home Page on Google Bookmark EERE: Alternative Fuels DataDepartment of Energy Your Density Isn'tOrigin of ContaminationHubs+18,new2004_v1.3_5.0.zipFlorida4Visitors3

  13. Modeling the Effects of Steam-Fuel Reforming Products on Low...

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

    the Effects of Steam-Fuel Reforming Products on Low Temperature Combustion of n-Heptane Modeling the Effects of Steam-Fuel Reforming Products on Low Temperature Combustion of...

  14. Dynamic First-Principles Molecular-Scale Model for Solid Oxide Fuel Cells V. Hugo Schmidt

    E-Print Network [OSTI]

    Dynamic First-Principles Molecular-Scale Model for Solid Oxide Fuel Cells V. Hugo Schmidt vs. current density i characteristics applies both to the Solid Oxide Fuel Cell (SOFC) and Solid

  15. Fact #718: March 12, 2012 Number of Flex-Fuel Models Offered...

    Energy Savers [EERE]

    Economy program for producing flex-fuel vehicles, which run on E-85, a blend of 85% ethanol and 15% gasoline, andor gasoline. Number of Flex Fuel Vehicle Models by...

  16. Mapping surface fuels using LIDAR and multispectral data fusion for fire behavior modeling 

    E-Print Network [OSTI]

    Mutlu, Muge

    2009-05-15T23:59:59.000Z

    Fires have become intense and more frequent in the United States. Improving the accuracy of mapping fuel models is essential for fuel management decisions and explicit fire behavior prediction for real-time support of suppression tactics...

  17. Webinar: DOE Updates JOBS and Economic Impacts of Fuel Cells (JOBS FC1.1) Model

    Broader source: Energy.gov [DOE]

    Video recording of the Fuel Cell Technologies Office webinar, DOE Updates JOBS and Economic Impacts of Fuel Cells (JOBS FC1.1) Model, originally presented on December 11, 2012.

  18. Determination of the proper operating range for the CAFCA IIB fuel cycle model

    E-Print Network [OSTI]

    Warburton, Jamie (Jamie L.)

    2007-01-01T23:59:59.000Z

    The fuel cycle simulation tool, CAFCA II was previously modified to produce the most recent version, CAFCA IIB. The code tracks the mass distribution of transuranics in the fuel cycle in one model and also projects costs ...

  19. Quantum phase transitions in fully connected spin models: an entanglement perspective

    E-Print Network [OSTI]

    M. Filippone; S. Dusuel; J. Vidal

    2011-02-28T23:59:59.000Z

    We consider a set of fully connected spins models that display first- or second-order transitions and for which we compute the ground-state entanglement in the thermodynamical limit. We analyze several entanglement measures (concurrence, R\\'enyi entropy, and negativity), and show that, in general, discontinuous transitions lead to a jump of these quantities at the transition point. Interestingly, we also find examples where this is not the case.

  20. Quantum phase transitions in fully-connected spin models: an entanglement perspective

    E-Print Network [OSTI]

    Filippone, M; Vidal, J

    2011-01-01T23:59:59.000Z

    We consider a set of fully-connected spins models which display first- or second-order transitions and for which we compute the ground-state entanglement in the thermodynamical limit. We analyze several entanglement measures (concurrence, R\\'enyi entropy, and negativity), and show that, in general, discontinuous transitions leads to a jump of these quantities at the transition point. Interestingly, we also find a puzzling example where it is not the case.

  1. Dynamics of the Oil Transition: Modeling Capacity, Costs, and Emissions

    E-Print Network [OSTI]

    Brandt, Adam R.; Farrell, Alexander E.

    2008-01-01T23:59:59.000Z

    oil-like hydrocarbon fuels from non-conventional petroleumto hydrocarbon-based substitutes for conventional petroleum.liquid hydrocarbons, avail- ability of conventional oil, the

  2. Modeling the transient operation of an endothermic fuel cooling system for high Mach number vehicle missions

    E-Print Network [OSTI]

    Williams, Mark Robert

    1993-01-01T23:59:59.000Z

    A computer model was developed to simulate the transient operation of a hypothetical endothermic fuel cooling system. The model simulated the performance of a cross-flow, shell and tube heat exchanger. This model was applied to a representative...

  3. Connecticut Fuel Cell Activities: Markets, Programs, and Models...

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

    Center for Advanced Technology, Inc. at the bi-monthly informational call for the DOE Fuel Cell Technologies Program on December 16, 2009 ccathydrogenct.pdf More Documents &...

  4. DOE Announces Webinars on Sandia Modeling Tool, Hydrogen Fueling

    Office of Environmental Management (EM)

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative1 First Use of Energy for All Purposes (Fuel and Nonfuel), 2002; Level: National5Sales for4,645 3,625 1,006 492 742 33 1112011AT&T,Office of Policy, OAPM | DepartmentIOffshore Wind Economic Impacts

  5. Used Fuel Degradation: Experimental and Modeling Report | Department of

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

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative1 First Use of Energy for All Purposes (Fuel and Nonfuel), 2002; Level: National5Sales for4,645 3,625 1,006 492 742EnergyOn AprilA group current C3EDepartment of Energy OfficeFact Sheet UraniumEnergy

  6. Fuel Cell Power (FCPower) Model | Open Energy Information

    Open Energy Info (EERE)

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Home Page onYou are now leaving Energy.gov You are now leaving Energy.gov You are8COaBulkTransmissionSitingProcess.pdf Jump1946865°, -86.0529604° ShowCounty, California:Frontier,FryeBio OnePower

  7. VISION Model for Vehicle Technologies and Alternative Fuels | Open Energy

    Open Energy Info (EERE)

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Home Page onYou are now leaving Energy.gov You are now leaving Energy.gov YouKizildere IRaghuraji Agro IndustriesTown of Ladoga,planning methodologies and toolsoperationWindEnergyInformation

  8. Supercomputers Fuel Global High-Resolution Climate Models

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

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative1 First Use of Energy for All Purposes (Fuel and Nonfuel), 2002; Level: National5Sales for4,645U.S. DOE Office of ScienceandMesa del SolStrengthening a solid ...Success Stories Touching TheCapture Turbulence in

  9. Model documentation renewable fuels module of the National Energy Modeling System

    SciTech Connect (OSTI)

    NONE

    1997-04-01T23:59:59.000Z

    This report documents the objectives, analytical approach, and design of the National Energy Modeling System (NEMS) Renewable Fuels Module (RFM) as it relates to the production of the 1997 Annual Energy Outlook forecasts. The report catalogues and describes modeling assumptions, computational methodologies, data inputs. and parameter estimation techniques. A number of offline analyses used in lieu of RFM modeling components are also described. This documentation report serves three purposes. First, it is a reference document for model analysts, model users, and the public interested in the construction and application of the RFM. Second, it meets the legal requirement of the Energy Information Administration (EIA) to provide adequate documentation in support of its models. Finally, such documentation facilitates continuity in EIA model development by providing information sufficient to perform model enhancements and data updates as part of EIA`s ongoing mission to provide analytical and forecasting information systems.

  10. Phase Transition in Ferromagnetic Ising Models with Non-Uniform External Magnetic Fields

    E-Print Network [OSTI]

    Rodrigo Bissacot; Leandro Cioletti

    2010-03-29T23:59:59.000Z

    In this article we study the phase transition phenomenon for the Ising model under the action of a non-uniform external magnetic field. We show that the Ising model on the hypercubic lattice with a summable magnetic field has a first-order phase transition and, for any positive (resp. negative) and bounded magnetic field, the model does not present the phase transition phenomenon whenever $\\liminf h_i> 0$, where ${\\bf h} = (h_i)_{i \\in \\Z^d}$ is the external magnetic field.

  11. Thermal modeling and temperature control of a PEM fuel cell system for forklift applications

    E-Print Network [OSTI]

    Berning, Torsten

    in automotive applications such as forklifts. In this paper we present a control-oriented dynamic modelThermal modeling and temperature control of a PEM fuel cell system for forklift applications simulation System modeling and control PEMFC a b s t r a c t Temperature changes in PEM fuel cell stacks

  12. Heavy Duty Diesel Particulate Matter and Fuel Consumption Modeling for Transportation Analysis

    E-Print Network [OSTI]

    Scora, George Alexander

    2011-01-01T23:59:59.000Z

    Model for Heavy Duty Diesel Vehicles. TransportationAir Contaminant Emissions from Diesel- fueled Engines. Factfor Measuring Emissions from Diesel Engines. 1. Regulated

  13. Webinar: DOE Launches JOBS and Economic Impacts of Fuel Cells (JOBS FC) Analysis Model

    Broader source: Energy.gov [DOE]

    Video recording and text version of the webinar titled, DOE Launches JOBS and Economic Impacts of Fuel Cells (JOBS FC) Analysis Model, originally presented on May 22, 2012.

  14. Stochastic Modeling and Direct Simulation of the Diffusion Media for Polymer Electrolyte Fuel Cells

    E-Print Network [OSTI]

    Schmidt, Volker

    Cells Yun Wang* and Xuhui Feng Renewable Energy Resources Lab (RERL) and National Fuel Cell Research the stochastic-model-based reconstruction of the gas diffusion layer (GDL) of polymer electrolyte fuel cells on pore-level transport and scrutinize the macroscopic approach vastly adopted in current fuel cell

  15. Heat and Mass Transfer Modeling of Dry Gases in the Cathode of PEM Fuel Cells

    E-Print Network [OSTI]

    Stockie, John

    Heat and Mass Transfer Modeling of Dry Gases in the Cathode of PEM Fuel Cells M.J. Kermani1 J and N2, through the cathode of a proton exchange membrane (PEM) fuel cell is studied numerically) an energy equation, written in a form that has enthalpy as the dependent variable. Keywords: PEM fuel cells

  16. The Hybrid Solid Oxide Fuel Cell (SOFC) and Gas Turbine (GT) Systems Steady State Modeling

    E-Print Network [OSTI]

    Paris-Sud XI, Université de

    The Hybrid Solid Oxide Fuel Cell (SOFC) and Gas Turbine (GT) Systems Steady State Modeling Penyarat Fuel Cells (SOFCs) are of great interest nowadays. The feature of SOFCs makes them suitable for hybrid plants offer high cycle efficiencies. In this work a hybrid solid oxide fuel cell and gas turbine power

  17. Phase-field modeling of three-phase electrode microstructures in solid oxide fuel cells

    E-Print Network [OSTI]

    Chen, Long-Qing

    Phase-field modeling of three-phase electrode microstructures in solid oxide fuel cells Qun Li, mechanical deformation, and heterogeneous damage accumulation in solid oxide fuel cell anodes J. Appl. Phys oxide fuel cell/gas turbine cycle J. Renewable Sustainable Energy 4, 043115 (2012) Electric

  18. CONTROL-ORIENTED MODELING AND ANALYSIS FOR AUTOMOTIVE FUEL CELL SYSTEMS

    E-Print Network [OSTI]

    Peng, Huei

    CONTROL-ORIENTED MODELING AND ANALYSIS FOR AUTOMOTIVE FUEL CELL SYSTEMS Jay T. Pukrushpan Huei Peng of Michigan Ann Arbor, Michigan 48109-2125 Email: pukrushp@umich.edu Abstract Fuel Cells are electrochemical regarded as a potential future stationary and mobile power source. The response of a fuel cell system

  19. Performance modeling and cell design for high concentration methanol fuel cells

    E-Print Network [OSTI]

    Chapter 50 Performance modeling and cell design for high concentration methanol fuel cells C. E The direct methanol fuel cell (DMFC) has become a lead- ing contender to replace the lithium-ion (Li density of liquid methanol (CH3OH) fuel is 4800 Wh l-1 , whereas the theoretical energy density of Li

  20. J. Electrochem. Soc., in press (1998) MicroMacroscopic Coupled Modeling of Batteries and Fuel Cells

    E-Print Network [OSTI]

    Wang, Chao-Yang

    , as well as various fuel cells, are widely used in consumer applications and electric vehicles materials and interface morphology and chemistry, has been developed for advanced batteries and fuel cells. Modeling and simulation of battery and fuel cell systems has been a rapidly expanding field, thanks in part

  1. Modelling and Design Optimization of Low Speed Fuel Cell Hybrid Electric Vehicles

    E-Print Network [OSTI]

    Victoria, University of

    Modelling and Design Optimization of Low Speed Fuel Cell Hybrid Electric Vehicles by Matthew Blair electric vehicles, empirical fuel cell system data has been incorporated into the NREL's vehicle design and simulation tool, ADVISOR (ADvanced Vehicle SimulatOR), to predict the performance of a low-speed, fuel cell

  2. J. Electrochem. Soc., in press (1998) Micro-Macroscopic Coupled Modeling of Batteries and Fuel Cells

    E-Print Network [OSTI]

    Wang, Chao-Yang

    , as well as various fuel cells, are widely used in consumer applications and electric vehicles and interface morphology and chemistry, has been developed for advanced batteries and fuel cells. Modeling and simulation of battery and fuel cell systems has been a rapidly expanding field, thanks in part

  3. Advanced modeling of large-scale oxy-fuel combustion processes

    E-Print Network [OSTI]

    Yin, Chungen

    Advanced modeling of large-scale oxy-fuel combustion processes Chungen Yin Department of Energy Technology, Aalborg University, DK-9220 Aalborg, Denmark, chy@et.aau.dk Introduction Oxy-fuel combustion simulations of various oxy- fuel combustion processes and experimental validation. Result · A new weighted

  4. Water Transport in PEM Fuel Cells: Advanced Modeling, Material Selection, Testing,

    E-Print Network [OSTI]

    Optimization J. Vernon Cole and Ashok Gidwani CFDRC Prepared for: DOE Hydrogen Fuel Cell Kickoff MeetingWater Transport in PEM Fuel Cells: Advanced Modeling, Material Selection, Testing, and Design fuel cell design and operation; Demonstrate improvements in water management resulting in improved

  5. Fuel-Cycle Energy and Emissions Analysis with the GREET Model | Department

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

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Home Page on Google Bookmark EERE: Alternative Fuels Data Center Home Page onYouTube YouTube Note: Since the.pdf Flash2006-52.pdf0.pdfDepartment ofEnergy 3 FuelModel | Department of

  6. Dynamics of the Oil Transition: Modeling Capacity, Costs, and Emissions

    E-Print Network [OSTI]

    Brandt, Adam R.; Farrell, Alexander E.

    2008-01-01T23:59:59.000Z

    entirely from steam-induced heavy oil production in Cali-from Venezuela’s extra-heavy oil reached about 0.6 Mbbl/d inliquid fuels. Heavy and extra-heavy oil are very viscous and

  7. Dynamics of the Oil Transition: Modeling Capacity, Costs, and Emissions

    E-Print Network [OSTI]

    Brandt, Adam R.; Farrell, Alexander E.

    2008-01-01T23:59:59.000Z

    D. J. and Cecchine, G. Oil shale development in the Unitedresources of some world oil-shale deposits. Technical Reportfor CO2 evolved from oil shale. Fuel Processing Technology,

  8. Modeling Transit Trip Time Using Archived Bus Dispatch System Data

    E-Print Network [OSTI]

    Bertini, Robert L.

    Transportation District of Oregon TriMet provides transit service in the three-county Portland metropolitan area that are automatically collected and archived for each bus, route, and stop every day. The Tri-County Metropolitan. TriMet has implemented a Bus Dispatch System BDS as a part of its overall service control

  9. Non-linear inversion modeling for Ultrasound Computer Tomography: transition from soft to hard tissues imaging

    E-Print Network [OSTI]

    Paris-Sud XI, Université de

    Non-linear inversion modeling for Ultrasound Computer Tomography: transition from soft to hard Marseille cedex 20, France ABSTRACT Ultrasound Computer Tomography (UCT) is an imaging technique which has experiments. Keyword: Ultrasound Computer Tomography, Inverse Born Approximation, Elliptical Projection

  10. A Statistical Model of Vehicle Emissions and Fuel Consumption

    E-Print Network [OSTI]

    Cappiello, Alessandra

    2002-09-17T23:59:59.000Z

    A number of vehicle emission models are overly simple, such as static speed-dependent models widely used in

  11. Husimi distribution and phase space analysis of Dicke model quantum phase transition

    E-Print Network [OSTI]

    E. Romera; R. del Real; M. Calixto

    2014-09-19T23:59:59.000Z

    The Husimi distribution is proposed for a phase space analysis of quantum phase transitions in the Dicke model of spin-boson interactions. We show that the inverse participation ratio and Wehrl entropy of the Husimi distribution give sharp signatures of the quantum phase transition. The analysis has been done using two frameworks: a numerical treatment and an analytical variational approximation. Additionally we have proposed a new characterization of the Dicke model quantum phase transition by means of the zeros of the Husimi distribution in the variational approach.

  12. Statistical mechanics model for the transit free energy of monatomic liquids

    E-Print Network [OSTI]

    Duane C. Wallace; Eric D. Chisolm; N. Bock; G. De Lorenzi-Venneri

    2010-04-19T23:59:59.000Z

    In applying Vibration-Transit (V-T) theory of liquid dynamics to the thermodynamic properties of monatomic liquids, the point has been reached where an improved model is needed for the small (approx. 10%) transit contribution. Toward this goal, an analysis of the available high-temperature experimental entropy data for elemental liquids was recently completed [D. C. Wallace, E. D. Chisolm, and N. Bock, Phys. Rev. B 79, 051201 (2009)]. This analysis yields a common curve of transit entropy vs. T/\\theta_{tr}, where T is temperature and \\theta_{tr} is a scaling temperature for each element. In the present paper, a statistical mechanics model is constructed for the transit partition function, and is calibrated to the experimental transit entropy curve. The model has two scalar parameters, and captures the temperature scaling of experiment. The calibrated model fits the experimental liquid entropy to high accuracy at all temperatures. With no additional parameters, the model also agrees with both experiment and molecular dynamics for the internal energy vs. T for Na. With the calibrated transit model, V-T theory provides equations subject to ab initio evaluation for thermodynamic properties of monatomic liquids. This will allow the range of applicability of the theory, and its overall accuracy, to be determined. More generally, the hypothesis of V-T theory, which divides the many-atom potential energy valleys into random and symmetric classes, can also be tested for its application beyond monatomic systems.

  13. Model documentation: Renewable Fuels Module of the National Energy Modeling System

    SciTech Connect (OSTI)

    Not Available

    1994-04-01T23:59:59.000Z

    This report documents the objectives, analytical approach, and design of the National Energy Modeling System (NEMS) Renewable Fuels Module (RFM) as it related to the production of the 1994 Annual Energy Outlook (AEO94) forecasts. The report catalogues and describes modeling assumptions, computational methodologies, data inputs, and parameter estimation techniques. A number of offline analyses used in lieu of RFM modeling components are also described. This documentation report serves two purposes. First, it is a reference document for model analysts, model users, and the public interested in the construction and application of the RFM. Second, it meets the legal requirement of the Energy Information Administration (EIA) to provide adequate documentation in support of its models. The RFM consists of six analytical submodules that represent each of the major renewable energy resources -- wood, municipal solid waste (MSW), solar energy, wind energy, geothermal energy, and alcohol fuels. Of these six, four are documented in the following chapters: municipal solid waste, wind, solar and biofuels. Geothermal and wood are not currently working components of NEMS. The purpose of the RFM is to define the technological and cost characteristics of renewable energy technologies, and to pass these characteristics to other NEMS modules for the determination of mid-term forecasted renewable energy demand.

  14. A Total Cost of Ownership Model for Low Temperature PEM Fuel...

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

    A Total Cost of Ownership Model for Low Temperature PEM Fuel Cells in Combined Heat and Power and Backup Power Applications A Total Cost of Ownership Model for Low Temperature PEM...

  15. An improved structural mechanics model for the FRAPCON nuclear fuel performance code

    E-Print Network [OSTI]

    Mieloszyk, Alexander James

    2012-01-01T23:59:59.000Z

    In order to provide improved predictions of Pellet Cladding Mechanical Interaction (PCMI) for the FRAPCON nuclear fuel performance code, a new model, the FRAPCON Radial-Axial Soft Pellet (FRASP) model, was developed. This ...

  16. A strategy for transition from a uranium fueled, open cycle SFR to a transuranic fueled, closed cycle sodium cooled fast reactor

    E-Print Network [OSTI]

    Richard, Joshua (Joshua Glenn)

    2012-01-01T23:59:59.000Z

    Reactors utilizing a highly energetic neutron spectrum, often termed fast reactors, offer large fuel utilization improvements over the thermal reactors currently used for nuclear energy generation. Conventional fast reactor ...

  17. Modeling hazardous fire potential within a completed fuel treatment network in the northern Sierra Nevada

    E-Print Network [OSTI]

    Stephens, Scott L.

    fuel models in treated areas had much less impact on hazardous fire potential, indicating a robust in untreated areas over time, result- ing in an increase in overall fire hazard. This suggests additionalModeling hazardous fire potential within a completed fuel treatment network in the northern Sierra

  18. Mapping surface fuels using LIDAR and multispectral data fusion for fire behavior modeling

    E-Print Network [OSTI]

    Mutlu, Muge

    2009-05-15T23:59:59.000Z

    outputs using fuel model maps, which differ in accuracy, in east Texas. Estimates of fuel models were compared with in situ data collected over 62 plots. Supervised image classification methods provided better accuracy (90.10%) with the fusion of airborne...

  19. Model documentation renewable fuels module of the National Energy Modeling System

    SciTech Connect (OSTI)

    NONE

    1995-06-01T23:59:59.000Z

    This report documents the objectives, analytical approach, and design of the National Energy Modeling System (NEMS) Renewable Fuels Module (RFM) as it relates to the production of the 1995 Annual Energy Outlook (AEO95) forecasts. The report catalogues and describes modeling assumptions, computational methodologies, data inputs, and parameter estimation techniques. A number of offline analyses used in lieu of RFM modeling components are also described. The RFM consists of six analytical submodules that represent each of the major renewable energy resources--wood, municipal solid waste (MSW), solar energy, wind energy, geothermal energy, and alcohol fuels. The RFM also reads in hydroelectric facility capacities and capacity factors from a data file for use by the NEMS Electricity Market Module (EMM). The purpose of the RFM is to define the technological, cost and resource size characteristics of renewable energy technologies. These characteristics are used to compute a levelized cost to be competed against other similarly derived costs from other energy sources and technologies. The competition of these energy sources over the NEMS time horizon determines the market penetration of these renewable energy technologies. The characteristics include available energy capacity, capital costs, fixed operating costs, variable operating costs, capacity factor, heat rate, construction lead time, and fuel product price.

  20. GREET 1.0 -- Transportation fuel cycles model: Methodology and use

    SciTech Connect (OSTI)

    Wang, M.Q.

    1996-06-01T23:59:59.000Z

    This report documents the development and use of the Greenhouse Gases, Regulated Emissions, and Energy Use in Transportation (GREET) model. The model, developed in a spreadsheet format, estimates the full fuel-cycle emissions and energy use associated with various transportation fuels for light-duty vehicles. The model calculates fuel-cycle emissions of five criteria pollutants (volatile organic compounds, Co, NOx, SOx, and particulate matter measuring 10 microns or less) and three greenhouse gases (carbon dioxide, methane, and nitrous oxide). The model also calculates the total fuel-cycle energy consumption, fossil fuel consumption, and petroleum consumption using various transportation fuels. The GREET model includes 17 fuel cycles: petroleum to conventional gasoline, reformulated gasoline, clean diesel, liquefied petroleum gas, and electricity via residual oil; natural gas to compressed natural gas, liquefied petroleum gas, methanol, hydrogen, and electricity; coal to electricity; uranium to electricity; renewable energy (hydropower, solar energy, and wind) to electricity; corn, woody biomass, and herbaceous biomass to ethanol; and landfill gases to methanol. This report presents fuel-cycle energy use and emissions for a 2000 model-year car powered by each of the fuels that are produced from the primary energy sources considered in the study.

  1. MELCOR model for an experimental 17x17 spent fuel PWR assembly.

    SciTech Connect (OSTI)

    Cardoni, Jeffrey

    2010-11-01T23:59:59.000Z

    A MELCOR model has been developed to simulate a pressurized water reactor (PWR) 17 x 17 assembly in a spent fuel pool rack cell undergoing severe accident conditions. To the extent possible, the MELCOR model reflects the actual geometry, materials, and masses present in the experimental arrangement for the Sandia Fuel Project (SFP). The report presents an overview of the SFP experimental arrangement, the MELCOR model specifications, demonstration calculation results, and the input model listing.

  2. Dynamics of the Oil Transition: Modeling Capacity, Costs, and Emissions

    E-Print Network [OSTI]

    Brandt, Adam R.; Farrell, Alexander E.

    2008-01-01T23:59:59.000Z

    market, allowing our model to focus on the supply of crude oil andterms of the model equations [7]). The oil market in ROMEO

  3. FRAPCON-3: Modifications to fuel rod material properties and performance models for high-burnup application

    SciTech Connect (OSTI)

    Lanning, D.D.; Beyer, C.E.; Painter, C.L.

    1997-12-01T23:59:59.000Z

    This volume describes the fuel rod material and performance models that were updated for the FRAPCON-3 steady-state fuel rod performance code. The property and performance models were changed to account for behavior at extended burnup levels up to 65 Gwd/MTU. The property and performance models updated were the fission gas release, fuel thermal conductivity, fuel swelling, fuel relocation, radial power distribution, solid-solid contact gap conductance, cladding corrosion and hydriding, cladding mechanical properties, and cladding axial growth. Each updated property and model was compared to well characterized data up to high burnup levels. The installation of these properties and models in the FRAPCON-3 code along with input instructions are provided in Volume 2 of this report and Volume 3 provides a code assessment based on comparison to integral performance data. The updated FRAPCON-3 code is intended to replace the earlier codes FRAPCON-2 and GAPCON-THERMAL-2. 94 refs., 61 figs., 9 tabs.

  4. Agenda for Transitioning the Transportation Sector: Exploring the Intersection of Hydrogen Fuel Cell and Natural Gas Vehicles Workshop

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

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Home Page on Google Bookmark EERE: Alternative Fuels DataDepartment of Energy Your Density Isn't Your Destiny: The Future of1Albuquerque, NM - Building America TopAgenda - DOE Tribal Leader r )

  5. SUMMARY FOR POLICYMAKERS Modeling Optimal Transition Pathways to a Low

    E-Print Network [OSTI]

    California at Davis, University of

    of California Energy and Climate Policies 2 capture and sequestration or increased supplies of wind and solar and trade, the low carbon fuel standard, GHG regulations for cars and trucks). These policies represent transformations of the energy system will be needed to meet the state's long-term goal of reducing GHG emissions

  6. Quantum-information approach to the quantum phase transition in the Kitaev honeycomb model

    SciTech Connect (OSTI)

    Cui Jian; Cao Junpeng; Fan Heng [Institute of Physics, Chinese Academy of Sciences, Beijing National Laboratory for Condensed Matter Physics, Beijing 100190 (China)

    2010-08-15T23:59:59.000Z

    The Kitaev honeycomb model with a topological phase transition at zero temperature is studied using the quantum-information method. Based on the exact solution of the ground state, the mutual information between two nearest sites and between two bonds with the greatest distance are obtained. It is found that the mutual information shows some singularities at the critical point where the system transits from the gapless phase to the gapped phase. Finite-size effects and scaling behavior are also studied. Our results indicate that the mutual information can serve as a good indicator of the topological phase transition. This is because the mutual information is believed to be able to catch some global correlation properties of the system. Meanwhile, this method has the advantages that the phase transition can be determined easily and the order parameters, which are hard to obtain for some topological phase transitions, are not necessarily known.

  7. Finite temperature spin-dynamics and phase transitions in spin-orbital models

    SciTech Connect (OSTI)

    Chen, C.-C.

    2010-04-29T23:59:59.000Z

    We study finite temperature properties of a generic spin-orbital model relevant to transition metal compounds, having coupled quantum Heisenberg-spin and Ising-orbital degrees of freedom. The model system undergoes a phase transition, consistent with that of a 2D Ising model, to an orbitally ordered state at a temperature set by short-range magnetic order. At low temperatures the orbital degrees of freedom freeze-out and the model maps onto a quantum Heisenberg model. The onset of orbital excitations causes a rapid scrambling of the spin spectral weight away from coherent spin-waves, which leads to a sharp increase in uniform magnetic susceptibility just below the phase transition, reminiscent of the observed behavior in the Fe-pnictide materials.

  8. JOBS Models: JOBS FC (Fuel Cells) and JOBS H2 (Hydrogen)

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

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Home Page on Google Bookmark EERE: Alternative Fuels Data Center Home Page onYouTube YouTube Note: Since the.pdfBreaking ofOil & Gas » Methane HydrateEnergyIs a SmallJ. E.at13,Models JOBS

  9. Fuel Cell Power Model Version 2: Startup Guide, System Designs, and Case Studies. Modeling Electricity, Heat, and Hydrogen Generation from Fuel Cell-Based Distributed Energy Systems

    SciTech Connect (OSTI)

    Steward, D.; Penev, M.; Saur, G.; Becker, W.; Zuboy, J.

    2013-06-01T23:59:59.000Z

    This guide helps users get started with the U.S. Department of Energy/National Renewable Energy Laboratory Fuel Cell Power (FCPower) Model Version 2, which is a Microsoft Excel workbook that analyzes the technical and economic aspects of high-temperature fuel cell-based distributed energy systems with the aim of providing consistent, transparent, comparable results. This type of energy system would provide onsite-generated heat and electricity to large end users such as hospitals and office complexes. The hydrogen produced could be used for fueling vehicles or stored for later conversion to electricity.

  10. Development and validation of a combustion model for a fuel cell off-gas burner

    E-Print Network [OSTI]

    Collins, William Tristan

    2008-10-14T23:59:59.000Z

    Development and Validation of a Combustion Model for a Fuel Cell Off-Gas Burner W. Tristan Collins Magdalene College University of Cambridge A dissertation submitted to the University of Cambridge for the degree of Doctor of Philosophy June 2008... Development and Validation of a Combustion Model for a Fuel Cell Off-Gas Burner W. Tristan Collins A low-emissions power generator comprising a solid oxide fuel cell coupled to a gas turbine has been developed by Rolls-Royce Fuel Cell Systems. As part...

  11. Fuel Efficient Diesel Particulate Filter (DPF) Modeling and Development

    SciTech Connect (OSTI)

    Stewart, Mark L.; Gallant, Thomas R.; Kim, Do Heui; Maupin, Gary D.; Zelenyuk, Alla

    2010-08-01T23:59:59.000Z

    The project described in this report seeks to promote effective diesel particulate filter technology with minimum fuel penalty by enhancing fundamental understanding of filtration mechanisms through targeted experiments and computer simulations. The overall backpressure of a filtration system depends upon complex interactions of particulate matter and ash with the microscopic pores in filter media. Better characterization of these phenomena is essential for exhaust system optimization. The acicular mullite (ACM) diesel particulate filter substrate is under continuing development by Dow Automotive. ACM is made up of long mullite crystals which intersect to form filter wall framework and protrude from the wall surface into the DPF channels. ACM filters have been demonstrated to effectively remove diesel exhaust particles while maintaining relatively low backpressure. Modeling approaches developed for more conventional ceramic filter materials, such as silicon carbide and cordierite, have been difficult to apply to ACM because of properties arising from its unique microstructure. Penetration of soot into the high-porosity region of projecting crystal structures leads to a somewhat extended depth filtration mode, but with less dramatic increases in pressure drop than are normally observed during depth filtration in cordierite or silicon carbide filters. Another consequence is greater contact between the soot and solid surfaces, which may enhance the action of some catalyst coatings in filter regeneration. The projecting crystals appear to provide a two-fold benefit for maintaining low backpressures during filter loading: they help prevent soot from being forced into the throats of pores in the lower porosity region of the filter wall, and they also tend to support the forming filter cake, resulting in lower average cake density and higher permeability. Other simulations suggest that soot deposits may also tend to form at the tips of projecting crystals due to the axial velocity component of exhaust moving down the filter inlet channel. Soot mass collected in this way would have a smaller impact on backpressure than soot forced into the flow restrictions deeper in the porous wall structure. This project has focused on the development of computational, analytical, and experimental techniques that are generally applicable to a wide variety of exhaust aftertreatment technologies. By helping to develop improved fundamental understanding pore-scale phenomena affecting filtration, soot oxidation, and NOX abatement, this cooperative research and development agreement (CRADA) has also assisted Dow Automotive in continuing development and commercialization of the ACM filter substrate. Over the course of this research project, ACM filters were successfully deployed on the Audi R10 TDI racecar which won the 24 Hours of LeMans endurance race in 2006, 2007, and 2008; and the 12 Hours of Sebring endurance race in 2006 and 2007. It would not have been possible for the R10 to compete in these traditionally gasoline-dominated events without reliable and effective exhaust particulate filtration. These successes demonstrated not only the performance of automotive diesel engines, but the efficacy of DPF technology as it was being deployed around the world to meet new emissions standards on consumer vehicles. During the course of this CRADA project, Dow Automotive commercialized their ACM DPF technology under the AERIFYTM DPF brand.

  12. Generation IV benchmarking of TRISO fuel performance models under accident conditions. Modeling input data

    SciTech Connect (OSTI)

    Blaise Collin

    2014-09-01T23:59:59.000Z

    This document presents the benchmark plan for the calculation of particle fuel performance on safety testing experiments that are representative of operational accidental transients. The benchmark is dedicated to the modeling of fission product release under accident conditions by fuel performance codes from around the world, and the subsequent comparison to post-irradiation experiment (PIE) data from the modeled heating tests. The accident condition benchmark is divided into three parts: the modeling of a simplified benchmark problem to assess potential numerical calculation issues at low fission product release; the modeling of the AGR-1 and HFR-EU1bis safety testing experiments; and, the comparison of the AGR-1 and HFR-EU1bis modeling results with PIE data. The simplified benchmark case, thereafter named NCC (Numerical Calculation Case), is derived from ''Case 5'' of the International Atomic Energy Agency (IAEA) Coordinated Research Program (CRP) on coated particle fuel technology [IAEA 2012]. It is included so participants can evaluate their codes at low fission product release. ''Case 5'' of the IAEA CRP-6 showed large code-to-code discrepancies in the release of fission products, which were attributed to ''effects of the numerical calculation method rather than the physical model''[IAEA 2012]. The NCC is therefore intended to check if these numerical effects subsist. The first two steps imply the involvement of the benchmark participants with a modeling effort following the guidelines and recommendations provided by this document. The third step involves the collection of the modeling results by Idaho National Laboratory (INL) and the comparison of these results with the available PIE data. The objective of this document is to provide all necessary input data to model the benchmark cases, and to give some methodology guidelines and recommendations in order to make all results suitable for comparison with each other. The participants should read this document thoroughly to make sure all the data needed for their calculations is provided in the document. Missing data will be added to a revision of the document if necessary.

  13. Analysis of the Transition to Hydrogen Fuel Cell Vehicles and the Potential Hydrogen Energy Infrastructure Requirements, March 2008

    Fuel Cell Technologies Publication and Product Library (EERE)

    Achieving a successful transition to hydrogen-powered vehicles in the U.S. automotive market will require strong and sustained commitment by hydrogen producers, vehicle manufacturers, transporters and

  14. Advanced Pellet Cladding Interaction Modeling Using the US DOE CASL Fuel Performance Code: Peregrine

    SciTech Connect (OSTI)

    Jason Hales; Various

    2014-06-01T23:59:59.000Z

    The US DOE’s Consortium for Advanced Simulation of LWRs (CASL) program has undertaken an effort to enhance and develop modeling and simulation tools for a virtual reactor application, including high fidelity neutronics, fluid flow/thermal hydraulics, and fuel and material behavior. The fuel performance analysis efforts aim to provide 3-dimensional capabilities for single and multiple rods to assess safety margins and the impact of plant operation and fuel rod design on the fuel thermomechanical- chemical behavior, including Pellet-Cladding Interaction (PCI) failures and CRUD-Induced Localized Corrosion (CILC) failures in PWRs. [1-3] The CASL fuel performance code, Peregrine, is an engineering scale code that is built upon the MOOSE/ELK/FOX computational FEM framework, which is also common to the fuel modeling framework, BISON [4,5]. Peregrine uses both 2-D and 3-D geometric fuel rod representations and contains a materials properties and fuel behavior model library for the UO2 and Zircaloy system common to PWR fuel derived from both open literature sources and the FALCON code [6]. The primary purpose of Peregrine is to accurately calculate the thermal, mechanical, and chemical processes active throughout a single fuel rod during operation in a reactor, for both steady state and off-normal conditions.

  15. Ab Initio Enhanced calphad Modeling of Actinide-Rich Nuclear Fuels

    SciTech Connect (OSTI)

    Morgan, Dane [Univ. of Wisconsin, Madison, WI (United States); Yang, Yong Austin [Univ. of Wisconsin, Madison, WI (United States)

    2013-10-28T23:59:59.000Z

    The process of fuel recycling is central to the Advanced Fuel Cycle Initiative (AFCI), where plutonium and the minor actinides (MA) Am, Np, and Cm are extracted from spent fuel and fabricated into new fuel for a fast reactor. Metallic alloys of U-Pu-Zr-MA are leading candidates for fast reactor fuels and are the current basis for fast spectrum metal fuels in a fully recycled closed fuel cycle. Safe and optimal use of these fuels will require knowledge of their multicomponent phase stability and thermodynamics (Gibbs free energies). In additional to their use as nuclear fuels, U-Pu-Zr-MA contain elements and alloy phases that pose fundamental questions about electronic structure and energetics at the forefront of modern many-body electron theory. This project will validate state-of-the-art electronic structure approaches for these alloys and use the resulting energetics to model U-Pu-Zr-MA phase stability. In order to keep the work scope practical, researchers will focus on only U-Pu-Zr-{Np,Am}, leaving Cm for later study. The overall objectives of this project are to: Provide a thermodynamic model for U-Pu-Zr-MA for improving and controlling reactor fuels; and, Develop and validate an ab initio approach for predicting actinide alloy energetics for thermodynamic modeling.

  16. The FIT 2.0 Model - Fuel-cycle Integration and Tradeoffs

    SciTech Connect (OSTI)

    Steven J. Piet; Nick R. Soelberg; Layne F. Pincock; Eric L. Shaber; Gregory M Teske

    2011-06-01T23:59:59.000Z

    All mass streams from fuel separation and fabrication are products that must meet some set of product criteria – fuel feedstock impurity limits, waste acceptance criteria (WAC), material storage (if any), or recycle material purity requirements such as zirconium for cladding or lanthanides for industrial use. These must be considered in a systematic and comprehensive way. The FIT model and the “system losses study” team that developed it [Shropshire2009, Piet2010b] are steps by the Fuel Cycle Technology program toward an analysis that accounts for the requirements and capabilities of each fuel cycle component, as well as major material flows within an integrated fuel cycle. This will help the program identify near-term R&D needs and set longer-term goals. This report describes FIT 2, an update of the original FIT model.[Piet2010c] FIT is a method to analyze different fuel cycles; in particular, to determine how changes in one part of a fuel cycle (say, fuel burnup, cooling, or separation efficiencies) chemically affect other parts of the fuel cycle. FIT provides the following: Rough estimate of physics and mass balance feasibility of combinations of technologies. If feasibility is an issue, it provides an estimate of how performance would have to change to achieve feasibility. Estimate of impurities in fuel and impurities in waste as function of separation performance, fuel fabrication, reactor, uranium source, etc.

  17. Thermomechanical modeling of the Spent Fuel Test-Climax

    SciTech Connect (OSTI)

    Butkovich, T.R.; Patrick, W.C.

    1986-02-01T23:59:59.000Z

    The Spent Fuel Test-Climax (SFT-C) was conducted to evaluate the feasibility of retrievable deep geologic storage of commercially generated spent nuclear-reactor fuel assemblies. One of the primary aspects of the test was to measure the thermomechanical response of the rock mass to the extensive heating of a large volume of rock. Instrumentation was emplaced to measure stress changes, relative motion of the rock mass, and tunnel closures during three years of heating from thermally decaying heat sources, followed by a six-month cooldown period. The calculations reported here were performed using the best available input parameters, thermal and mechanical properties, and power levels which were directly measured or inferred from measurements made during the test. This report documents the results of these calculations and compares the results with selected measurements made during heating and cooling of the SFT-C.

  18. KINETIC MODELING OF FUEL EFFECTS OVER A WIDE RANGE OF CHEMISTRY, PROPERTIES, AND SOURCES

    SciTech Connect (OSTI)

    Bunting, Bruce G [ORNL] [ORNL; Bunce, Michael [ORNL] [ORNL; Niak, Chitralkumar [Reaction Design] [Reaction Design; Puduppakkam, Karthik [Reaction Design] [Reaction Design

    2012-01-01T23:59:59.000Z

    Kinetic modeling is an important tool for engine design and can also be used for engine tuning and to study response to fuel chemistry and properties before an engine configuration is physically built and tested. Methodologies needed for studying fuel effects include development of fuel kinetic mechanisms for pure compounds, tools for designing surrogate blends of pure compounds that mimic a desired market fuel, and tools for reducing kinetic mechanisms to a size that allows inclusion in complex CFD engine models. In this paper, we demonstrate the use of these tools to reproduce engine results for a series of research diesel fuels using surrogate fuels in an engine and then modeling results with a simple 2 component surrogate blend with physical properties adjusted to vary fuel volatility. Results indicate that we were reasonably successful in mimicking engine performance of real fuels with blends of pure compounds. We were also successful in spanning the range of the experimental data using CFD and kinetic modeling, but further tuning and matching will be needed to exactly match engine performance of the real and surrogate fuels.

  19. Modeling of the performance of weapons MOX fuel in light water reactors

    SciTech Connect (OSTI)

    Alvis, J.; Bellanger, P.; Medvedev, P.G.; Peddicord, K.L. [Texas A and M Univ., College Station, TX (United States). Nuclear Engineering Dept.; Gellene, G.I. [Texas Tech Univ., Lubbock, TX (United States). Dept. of Chemistry and Biochemistry

    1999-05-01T23:59:59.000Z

    Both the Russian Federation and the US are pursing mixed uranium-plutonium oxide (MOX) fuel in light water reactors (LWRs) for the disposition of excess plutonium from disassembled nuclear warheads. Fuel performance models are used which describe the behavior of MOX fuel during irradiation under typical power reactor conditions. The objective of this project is to perform the analysis of the thermal, mechanical, and chemical behavior of weapons MOX fuel pins under LWR conditions. If fuel performance analysis indicates potential questions, it then becomes imperative to assess the fuel pin design and the proposed operating strategies to reduce the probability of clad failure and the associated release of radioactive fission products into the primary coolant system. Applying the updated code to anticipated fuel and reactor designs, which would be used for weapons MOX fuel in the US, and analyzing the performance of the WWER-100 fuel for Russian weapons plutonium disposition are addressed in this report. The COMETHE code was found to do an excellent job in predicting fuel central temperatures. Also, despite minor predicted differences in thermo-mechanical behavior of MOX and UO{sub 2} fuels, the preliminary estimate indicated that, during normal reactor operations, these deviations remained within limits foreseen by fuel pin design.

  20. Winding Transitions at Finite Energy and Temperature: An O(3) Model

    E-Print Network [OSTI]

    Salman Habib; Emil Mottola; Peter Tinyakov

    1996-08-14T23:59:59.000Z

    Winding number transitions in the two dimensional softly broken O(3) nonlinear sigma model are studied at finite energy and temperature. New periodic instanton solutions which dominate the semiclassical transition amplitudes are found analytically at low energies, and numerically for all energies up to the sphaleron scale. The Euclidean period beta of these finite energy instantons increases with energy, contrary to the behavior found in the abelian Higgs model or simple one dimensional systems. This results in a sharp crossover from instanton dominated tunneling to sphaleron dominated thermal activation at a certain critical temperature. Since this behavior is traceable to the soft breaking of conformal invariance by the mass term in the sigma model, semiclassical winding number transition amplitudes in the electroweak theory in 3+1 dimensions should exhibit a similar sharp crossover. We argue that this is indeed the case in the standard model for M_H < 4 M_W.

  1. User Guide for VISION 3.4.7 (Verifiable Fuel Cycle Simulation) Model

    SciTech Connect (OSTI)

    Jacob J. Jacobson; Robert F. Jeffers; Gretchen E. Matthern; Steven J. Piet; Wendell D. Hintze

    2011-07-01T23:59:59.000Z

    The purpose of this document is to provide a guide for using the current version of the Verifiable Fuel Cycle Simulation (VISION) model. This is a complex model with many parameters and options; the user is strongly encouraged to read this user guide before attempting to run the model. This model is an R&D work in progress and may contain errors and omissions. It is based upon numerous assumptions. This model is intended to assist in evaluating 'what if' scenarios and in comparing fuel, reactor, and fuel processing alternatives at a systems level. The model is not intended as a tool for process flow and design modeling of specific facilities nor for tracking individual units of fuel or other material through the system. The model is intended to examine the interactions among the components of a fuel system as a function of time varying system parameters; this model represents a dynamic rather than steady-state approximation of the nuclear fuel system. VISION models the nuclear cycle at the system level, not individual facilities, e.g., 'reactor types' not individual reactors and 'separation types' not individual separation plants. Natural uranium can be enriched, which produces enriched uranium, which goes into fuel fabrication, and depleted uranium (DU), which goes into storage. Fuel is transformed (transmuted) in reactors and then goes into a storage buffer. Used fuel can be pulled from storage into either separation or disposal. If sent to separations, fuel is transformed (partitioned) into fuel products, recovered uranium, and various categories of waste. Recycled material is stored until used by its assigned reactor type. VISION is comprised of several Microsoft Excel input files, a Powersim Studio core, and several Microsoft Excel output files. All must be co-located in the same folder on a PC to function. You must use Powersim Studio 8 or better. We have tested VISION with the Studio 8 Expert, Executive, and Education versions. The Expert and Education versions work with the number of reactor types of 3 or less. For more reactor types, the Executive version is currently required. The input files are Excel2003 format (xls). The output files are macro-enabled Excel2007 format (xlsm). VISION 3.4 was designed with more flexibility than previous versions, which were structured for only three reactor types - LWRs that can use only uranium oxide (UOX) fuel, LWRs that can use multiple fuel types (LWR MF), and fast reactors. One could not have, for example, two types of fast reactors concurrently. The new version allows 10 reactor types and any user-defined uranium-plutonium fuel is allowed. (Thorium-based fuels can be input but several features of the model would not work.) The user identifies (by year) the primary fuel to be used for each reactor type. The user can identify for each primary fuel a contingent fuel to use if the primary fuel is not available, e.g., a reactor designated as using mixed oxide fuel (MOX) would have UOX as the contingent fuel. Another example is that a fast reactor using recycled transuranic (TRU) material can be designated as either having or not having appropriately enriched uranium oxide as a contingent fuel. Because of the need to study evolution in recycling and separation strategies, the user can now select the recycling strategy and separation technology, by year.

  2. Critical points and transitions in an electric power transmission model for cascading failure blackouts

    E-Print Network [OSTI]

    Dobson, Ian

    Critical points and transitions in an electric power transmission model for cascading failure September 2002 Cascading failures in large-scale electric power transmission systems are an important cause, we examine cascading failure in a simplified transmission system model as load power demand

  3. A Phase Transition Model for By Christopher L. DeMarco

    E-Print Network [OSTI]

    by the electric power systems application. Efforts to date on these problems for power networks have focused circuits (including nonlinear inductive and capacitive elements) and classical models for electric powerA Phase Transition Model for By Christopher L. DeMarco A s the scale of engineered systems

  4. Proton-coupled electron transfer reactions in solution: Molecular dynamics with quantum transitions for model systems

    E-Print Network [OSTI]

    Hammes-Schiffer, Sharon

    Proton-coupled electron transfer reactions in solution: Molecular dynamics with quantum transitions A general minimal model for proton-coupled electron transfer PCET reactions in solution is presented. This model consists of three coupled degrees of freedom that represent an electron, a proton, and a solvent

  5. Modeling and Analysis of FCM UN TRISO Fuel Using the PARFUME Code

    SciTech Connect (OSTI)

    Blaise Collin

    2013-09-01T23:59:59.000Z

    The PARFUME (PARticle Fuel ModEl) modeling code was used to assess the overall fuel performance of uranium nitride (UN) tri-structural isotropic (TRISO) ceramic fuel in the frame of the design and development of Fully Ceramic Matrix (FCM) fuel. A specific modeling of a TRISO particle with UN kernel was developed with PARFUME, and its behavior was assessed in irradiation conditions typical of a Light Water Reactor (LWR). The calculations were used to access the dimensional changes of the fuel particle layers and kernel, including the formation of an internal gap. The survivability of the UN TRISO particle was estimated depending on the strain behavior of the constituent materials at high fast fluence and burn-up. For nominal cases, internal gas pressure and representative thermal profiles across the kernel and layers were determined along with stress levels in the pyrolytic carbon (PyC) and silicon carbide (SiC) layers. These parameters were then used to evaluate fuel particle failure probabilities. Results of the study show that the survivability of UN TRISO fuel under LWR irradiation conditions might only be guaranteed if the kernel and PyC swelling rates are limited at high fast fluence and burn-up. These material properties are unknown at the irradiation levels expected to be reached by UN TRISO fuel in LWRs. Therefore, more effort is needed to determine them and positively conclude on the applicability of FCM fuel to LWRs.

  6. Chemical Kinetic Modeling of Non-Petroleum Based Fuels

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

    FY11 Objectives: * Develop a chemical kinetic models for an actual components in biodiesel Methyl palmitate Methyl linoleate Methyl linolenate * Develop a chemical...

  7. Modeling the performance of high burnup thoria and urania PWR fuel

    E-Print Network [OSTI]

    Long, Yun, 1972-

    2002-01-01T23:59:59.000Z

    Fuel performance models have been developed to assess the performance of ThO?-UO? fuels that can be operated to a high burnup up to 80-100MWd/kgHM in current and future Light Water Reactors (LWRs). Among the various issues ...

  8. Computational Modeling of Electrolyte/Cathode Interfaces in Proton Exchange Membrane Fuel Cells

    E-Print Network [OSTI]

    Bjørnstad, Ottar Nordal

    Computational Modeling of Electrolyte/Cathode Interfaces in Proton Exchange Membrane Fuel Cells Dr Proton exchange membrane fuel cells (PEMFCs) are alternative energy conversion devices that efficiently. The fundamental relationship between operating conditions and device performance will help to optimize the device

  9. Transition probabilities for piecewise affine models of genetic networks Madalena Chaves, Etienne Farcot and Jean-Luc Gouze

    E-Print Network [OSTI]

    Paris-Sud XI, Université de

    Transition probabilities for piecewise affine models of genetic networks Madalena Chaves, Etienne that trajectories follow a path in a transition graph. In this paper, a probabilistic interpretation is given for the transition between two nodes A and B, based on the volume of the initial conditions on hyperrectangle A whose

  10. Coherent/incoherent metal transition in a holographic model

    E-Print Network [OSTI]

    Keun-Young Kim; Kyung Kiu Kim; Yunseok Seo; Sang-Jin Sin

    2014-12-13T23:59:59.000Z

    We study AC electric($\\sigma$), thermoelectric($\\alpha$), and thermal($\\bar{\\kappa}$) conductivities in a holographic model, which is based on 3+1 dimensional Einstein-Maxwell-scalar action. There is momentum relaxation due to massless scalar fields linear to spatial coordinate. The model has three field theory parameters: temperature($T$), chemical potential($\\mu$), and effective impurity($\\beta$). At low frequencies, if $\\beta \\mu$ the shape of peak deviates from the Drude form(incoherent metal). At intermediate frequencies($T<\\omega<\\mu$), we have analysed numerical data of three conductivities($\\sigma, \\alpha, \\bar{\\kappa}$) for a wide variety of parameters, searching for scaling laws, which are expected from either experimental results on cuprates superconductors or some holographic models. In the model we study, we find no clear signs of scaling behaviour.

  11. Dynamics of the Oil Transition: Modeling Capacity, Costs, and Emissions

    E-Print Network [OSTI]

    Brandt, Adam R.; Farrell, Alexander E.

    2008-01-01T23:59:59.000Z

    and income on energy and oil demand. Energy Journal, 23(1):conventional oil supply and demand. But, interestingly,World crude oil and natural gas: a demand and supply model.

  12. Model study of dissipation in quantum phase transitions

    E-Print Network [OSTI]

    Subhasis Sinha; Sushanta Dattagupta

    2011-04-28T23:59:59.000Z

    We consider a prototypical system of an infinite range transverse field Ising model coupled to a bosonic bath. By integrating out the bosonic degrees, an effective anisotropic Heisenberg model is obtained for the spin system. The phase diagram of the latter is calculated as a function of coupling to the heat bath and the transverse magnetic field. Collective excitations at low temeratures are assessed within a spin-wave like analysis that exhibits a vanishing energy gap at the quantum critical point. We also consider another limit where the system reduces to a generalized spin-boson model of two interacting spins. By increasing the coupling strength with the heat bath, the two-spin wavefunction changes from an entangled state to a factorized state of two spins which are aligned along the transverse field. We also discuss the possible realization and application of the model to different physical systems.

  13. Modeling CANDU-6 liquid zone controllers for effects of thorium-based fuels

    SciTech Connect (OSTI)

    St-Aubin, E.; Marleau, G. [Ecole Polytechnique de Montreal, P.O. Box 6079, stn. Centre Ville, Montreal, QC H3C 3A7 (Canada)

    2012-07-01T23:59:59.000Z

    We use the DRAGON code to model the CANDU-6 liquid zone controllers and evaluate the effects of thorium-based fuels on their incremental cross sections and reactivity worth. We optimize both the numerical quadrature and spatial discretization for 2D cell models in order to provide accurate fuel properties for 3D liquid zone controller supercell models. We propose a low computer cost parameterized pseudo-exact 3D cluster geometries modeling approach that avoids tracking issues on small external surfaces. This methodology provides consistent incremental cross sections and reactivity worths when the thickness of the buffer region is reduced. When compared with an approximate annular geometry representation of the fuel and coolant region, we observe that the cluster description of fuel bundles in the supercell models does not increase considerably the precision of the results while increasing substantially the CPU time. In addition, this comparison shows that it is imperative to finely describe the liquid zone controller geometry since it has a strong impact of the incremental cross sections. This paper also shows that liquid zone controller reactivity worth is greatly decreased in presence of thorium-based fuels compared to the reference natural uranium fuel, since the fission and the fast to thermal scattering incremental cross sections are higher for the new fuels. (authors)

  14. GREET 1.5 - transportation fuel-cycle model - Vol. 1 : methodology, development, use, and results.

    SciTech Connect (OSTI)

    Wang, M. Q.

    1999-10-06T23:59:59.000Z

    This report documents the development and use of the most recent version (Version 1.5) of the Greenhouse Gases, Regulated Emissions, and Energy Use in Transportation (GREET) model. The model, developed in a spreadsheet format, estimates the full fuel-cycle emissions and energy associated with various transportation fuels and advanced vehicle technologies for light-duty vehicles. The model calculates fuel-cycle emissions of five criteria pollutants (volatile organic compounds, carbon monoxide, nitrogen oxides, particulate matter with diameters of 10 micrometers or less, and sulfur oxides) and three greenhouse gases (carbon dioxide, methane, and nitrous oxide). The model also calculates total energy consumption, fossil fuel consumption, and petroleum consumption when various transportation fuels are used. The GREET model includes the following cycles: petroleum to conventional gasoline, reformulated gasoline, conventional diesel, reformulated diesel, liquefied petroleum gas, and electricity via residual oil; natural gas to compressed natural gas, liquefied natural gas, liquefied petroleum gas, methanol, Fischer-Tropsch diesel, dimethyl ether, hydrogen, and electricity; coal to electricity; uranium to electricity; renewable energy (hydropower, solar energy, and wind) to electricity; corn, woody biomass, and herbaceous biomass to ethanol; soybeans to biodiesel; flared gas to methanol, dimethyl ether, and Fischer-Tropsch diesel; and landfill gases to methanol. This report also presents the results of the analysis of fuel-cycle energy use and emissions associated with alternative transportation fuels and advanced vehicle technologies to be applied to passenger cars and light-duty trucks.

  15. Modeling Water Management in Polymer-Electrolyte Fuel Cells

    SciTech Connect (OSTI)

    Department of Chemical Engineering, University of California, Berkeley; Weber, Adam; Weber, Adam Z.; Balliet, Ryan; Gunterman, Haluna P.; Newman, John

    2007-09-07T23:59:59.000Z

    Fuel cells may become the energy-delivery devices of the 21st century with realization of a carbon-neutral energy economy. Although there are many types of fuel cells, polymerelectrolyte fuel cells (PEFCs) are receiving the most attention for automotive and small stationary applications. In a PEFC, hydrogen and oxygen are combined electrochemically to produce water, electricity, and waste heat. During the operation of a PEFC, many interrelated and complex phenomena occur. These processes include mass and heat transfer, electrochemical reactions, and ionic and electronic transport. Most of these processes occur in the through-plane direction in what we term the PEFC sandwich as shown in Figure 1. This sandwich comprises multiple layers including diffusion media that can be composite structures containing a macroporous gas-diffusion layer (GDL) and microporous layer (MPL), catalyst layers (CLs), flow fields or bipolar plates, and a membrane. During operation fuel is fed into the anode flow field, moves through the diffusion medium, and reacts electrochemically at the anode CL to form hydrogen ions and electrons. The oxidant, usually oxygen in air, is fed into the cathode flow field, moves through the diffusion medium, and is electrochemically reduced at the cathode CL by combination with the generated protons and electrons. The water, either liquid or vapor, produced by the reduction of oxygen at the cathode exits the PEFC through either the cathode or anode flow field. The electrons generated at the anode pass through an external circuit and may be used to perform work before they are consumed at the cathode. The performance of a PEFC is most often reported in the form of a polarization curve, as shown in Figure 2. Roughly speaking, the polarization curve can be broken down into various regions. First, it should be noted that the equilibrium potential differs from the open-circuit voltage due mainly to hydrogen crossover through the membrane (i.e., a mixed potential on the cathode) and the resulting effects of the kinetic reactions. Next, at low currents, the behavior of a PEFC is dominated by kinetic losses. These losses mainly stem from the high overpotential of the oxygen-reduction reaction (ORR). As the current is increased, ohmic losses become a factor in lowering the overall cell potential. These ohmic losses are mainly from ionic losses in the electrodes and separator. At high currents, mass-transport limitations become increasingly important. These losses are due to reactants not being able to reach the electrocatalytic sites. Key among the issues facing PEFCs today is water management. Due to their low operating temperature (< 100 C), water exists in both liquid and vapor phases. Furthermore, state-of-the-art membranes require the use of water to provide high conductivity and fast proton transport. Thus, there is a tradeoff between having enough water for proton conduction (ohmic losses), but not too much or else the buildup of liquid water will cause a situation in which the reactant-gas-transport pathways are flooded (mass-transfer limitations). Figure 3 displays experimental evidence of the effects of water management on performance. In Figure 3(a), a neutron image of water content displays flooding near the outlet of the cell due to accumulation of liquid water and a decrease in the gas flowrates. The serpentine flow field is clearly visible with the water mainly underneath the ribs. Figure 3(b) shows polarization performance at 0.4 and 0.8 V and high-frequency resistance at 0.8 V as a function of cathode humidification temperature. At low current densities, as the inlet air becomes more humid, the membrane resistance decreases, and the performance increases. At higher current densities, the same effect occurs; however, the higher temperatures and more humid air also results in a lower inlet oxygen partial pressure.

  16. Development and use of the GREET model to estimate fuel-cycle energy use and emissions of various transportation technologies and fuels

    SciTech Connect (OSTI)

    Wang, M.Q.

    1996-03-01T23:59:59.000Z

    This report documents the development and use of the Greenhouse Gases, Regulated Emissions, and Energy Use in Transportation (GREET) model. The model, developed in a spreadsheet format, estimates the full fuel- cycle emissions and energy use associated with various transportation fuels for light-duty vehicles. The model calculates fuel-cycle emissions of five criteria pollutants (volatile organic compounds, carbon monoxide, nitrogen oxides, sulfur oxides, and particulate matter measuring 10 microns or less) and three greenhouse gases (carbon dioxide, methane, and nitrous oxide). The model also calculates the total fuel-cycle energy consumption, fossil fuel consumption, and petroleum consumption using various transportation fuels. The GREET model includes 17 fuel cycles: petroleum to conventional gasoline, reformulated gasoline, clean diesel, liquefied petroleum gas, and electricity via residual oil; natural gas to compressed natural gas, liquefied petroleum gas, methanol, hydrogen, and electricity; coal to electricity; uranium to electricity; renewable energy (hydrogen, solar energy, and wind) to electricity; corn, woody biomass, and herbaceous biomass to ethanol; and landfill gases to methanol. This report presents fuel-cycle energy use and emissions for a 2000 model-year car powered by each of the fuels that are produced from the primary energy sources considered in the study.

  17. Quantum phase transition in the $Z_3$ Kitaev-Potts model

    E-Print Network [OSTI]

    Razieh Mohseninia; Saeed S. Jahromi; Laleh Memarzadeh; Vahid Karimipour

    2015-05-21T23:59:59.000Z

    The stability of the topological order phase induced by the $Z_3$ Kitaev model, which is a candidate for fault-tolerant quantum computation, against the local order phase induced by the 3-State Potts model is studied. We show that the low energy sector of the Kitaev-Potts model is mapped to the Potts model in the presence of transverse magnetic field. Our study relies on two high-order series expansion based on continuous unitary transformations in the limits of small- and large-Potts couplings as well as mean-field approximation. Our analysis reveals that the topological phase of the $Z_3$ Kitaev model breaks down to the Potts model through a first order phase transition. We capture the phase transition by analysis of the ground state energy, one-quasiparticle gap and geometric measure of entanglement.

  18. Beryllium Impregnation of Uranium Fuel: Thermal Modeling of Cylindrical Objects for Efficiency Evaluation

    E-Print Network [OSTI]

    Lynn, Nicholas

    2011-08-04T23:59:59.000Z

    With active research projects related to nuclear waste immobilization and high conductivity nuclear fuels, a thermal model has been developed to simulate the temperature profile within a heat generating cylinder in order to imitate the behavior...

  19. A decision-support model for managing the fuel inventory of a Panamanian generating company

    E-Print Network [OSTI]

    Perez-Franco, Roberto, 1976-

    2004-01-01T23:59:59.000Z

    Bahia Las Minas Corp (BLM) is a fuelpowered generating company in the Panamanian power system. The purpose of this thesis is to design and evaluate a decision-support model for managing the fuel inventory of this company. ...

  20. Beryllium Impregnation of Uranium Fuel: Thermal Modeling of Cylindrical Objects for Efficiency Evaluation 

    E-Print Network [OSTI]

    Lynn, Nicholas

    2011-08-04T23:59:59.000Z

    With active research projects related to nuclear waste immobilization and high conductivity nuclear fuels, a thermal model has been developed to simulate the temperature profile within a heat generating cylinder in order to imitate the behavior...

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

    SciTech Connect (OSTI)

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

    2010-05-01T23:59:59.000Z

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

  2. A Total Cost of Ownership Model for Low Temperature PEM Fuel...

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

    LBNL-6772E A Total Cost of Ownership Model for Low Temperature PEM Fuel Cells in Combined Heat and Power and Backup Power Applications Max Wei, Timothy Lipman 1 , Ahmad Mayyas 1 ,...

  3. Examining hydrogen transitions.

    SciTech Connect (OSTI)

    Plotkin, S. E.; Energy Systems

    2007-03-01T23:59:59.000Z

    This report describes the results of an effort to identify key analytic issues associated with modeling a transition to hydrogen as a fuel for light duty vehicles, and using insights gained from this effort to suggest ways to improve ongoing modeling efforts. The study reported on here examined multiple hydrogen scenarios reported in the literature, identified modeling issues associated with those scenario analyses, and examined three DOE-sponsored hydrogen transition models in the context of those modeling issues. The three hydrogen transition models are HyTrans (contractor: Oak Ridge National Laboratory), MARKAL/DOE* (Brookhaven National Laboratory), and NEMS-H2 (OnLocation, Inc). The goals of these models are (1) to help DOE improve its R&D effort by identifying key technology and other roadblocks to a transition and testing its technical program goals to determine whether they are likely to lead to the market success of hydrogen technologies, (2) to evaluate alternative policies to promote a transition, and (3) to estimate the costs and benefits of alternative pathways to hydrogen development.

  4. Fuel Cell Power Model for CHHP System Economics and Performance...

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

    Cell Tri-Generation System Case Study using the H2A Stationary Model Tri-Generation Success Story: World's First Tri-Gen Energy Station-Fountain Valley Biogas Opportunities Roadmap...

  5. DOE Announces Webinars on Sandia Modeling Tool, Hydrogen Fueling...

    Office of Environmental Management (EM)

    models for the Sandia tool were created, and explore how they can be used. In addition, case studies focusing on potential applications for tribes will be presented. Register to...

  6. Model Compound Studies of Fuel Cell Membrane Degradation

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

    fluoride handle Model compound work, with nmr & LCMS workup has begun in our lab Acknowledgement Acknowledgement Financial Support Provided by DOE (Contract DE-FC36-03GO13098)...

  7. Transition from AdS universe to DS universe in the BPP model

    E-Print Network [OSTI]

    Wontae Kim; Myungseok Yoon

    2007-03-03T23:59:59.000Z

    It can be shown that in the BPP model the smooth phase transition from the asymptotically decelerated AdS universe to the asymptotically accelerated DS universe is possible by solving the modified semiclassical equations of motion. This transition comes from noncommutative Poisson algebra, which gives the constant curvature scalars asymptotically. The decelerated expansion of the early universe is due to the negative energy density with the negative pressure induced by quantum back reaction, and the accelerated late-time universe comes from the positive energy and the negative pressure which behave like dark energy source in recent cosmological models.

  8. Nonlinear modelling of polymer electrolyte membrane fuel cell stack using nonlinear cancellation technique

    SciTech Connect (OSTI)

    Barus, R. P. P., E-mail: rismawan.ppb@gmail.com [Engineering Physics, Faculty of Industrial Technology, Institut Teknologi Bandung, Jalan Ganesa 10 Bandung and Centre for Material and Technical Product, Jalan Sangkuriang No. 14 Bandung (Indonesia); Tjokronegoro, H. A.; Leksono, E. [Engineering Physics, Faculty of Industrial Technology, Institut Teknologi Bandung, Jalan Ganesa 10 Bandung (Indonesia); Ismunandar [Chemistry Study, Faculty of Mathematics and Science, Institut Teknologi Bandung, Jalan Ganesa 10 Bandung (Indonesia)

    2014-09-25T23:59:59.000Z

    Fuel cells are promising new energy conversion devices that are friendly to the environment. A set of control systems are required in order to operate a fuel cell based power plant system optimally. For the purpose of control system design, an accurate fuel cell stack model in describing the dynamics of the real system is needed. Currently, linear model are widely used for fuel cell stack control purposes, but it has limitations in narrow operation range. While nonlinear models lead to nonlinear control implemnetation whos more complex and hard computing. In this research, nonlinear cancellation technique will be used to transform a nonlinear model into a linear form while maintaining the nonlinear characteristics. The transformation is done by replacing the input of the original model by a certain virtual input that has nonlinear relationship with the original input. Then the equality of the two models is tested by running a series of simulation. Input variation of H2, O2 and H2O as well as disturbance input I (current load) are studied by simulation. The error of comparison between the proposed model and the original nonlinear model are less than 1 %. Thus we can conclude that nonlinear cancellation technique can be used to represent fuel cell nonlinear model in a simple linear form while maintaining the nonlinear characteristics and therefore retain the wide operation range.

  9. Comment on "A Look at the Multiphase Mixture Model for PEM Fuel Cell Simulations"

    E-Print Network [OSTI]

    Comment on "A Look at the Multiphase Mixture Model for PEM Fuel Cell Simulations" [Electrochem received June 2, 2008. Published December 11, 2008. The article of Gurau et al.1 discusses the multiphase mixture M2 model developed by Wang and co-workers2-6 over the last 15 years for the modeling of multiphase

  10. An evaluation of thermal modeling techniques utilized for nuclear fuel rods 

    E-Print Network [OSTI]

    Simmons, Jeffrey Warren

    1989-01-01T23:59:59.000Z

    AN EVALUATION OF THERMAL MODELING TECHNIQUES UTILIZED FOR NUCLEAR FUEL RODS A Thesis by JEFFREY WARREN SIMMONS Submitted to the Office of Graduate Studies of Texas Asr M University in partial fulfillment of the requirements for the degree... of MASTER OF SCIENCE August 1989 Major Subject: Nuclear Engineering AN EVALUATION OF THERMAL MODELING TECHNIQUES UTILIZED FOR NUCLEAR FUEL RODS A Thesis by ~Y WARREN SIMMONS Approved as to style and content by: K. L. Peddicord (Chair of Committee...

  11. The Hydrogen Infrastructure Transition Model (HIT) & Its Application in Optimizing a 50-year Hydrogen Infrastructure for Urban Beijing

    E-Print Network [OSTI]

    Lin, Zhenhong; Ogden, J; Fan, Yueyue; Sperling, Dan

    2006-01-01T23:59:59.000Z

    Zoia (2005). "Hydrogen infrastructure strategic planningITS—RR—06—05 The Hydrogen Infrastructure Transition Model (a 50-year Hydrogen Infrastructure for Urban Beijing Zhenhong

  12. The Hydrogen Infrastructure Transition (HIT) Model and Its Application in Optimizing a 50-year Hydrogen Infrastructure for Urban Beijing

    E-Print Network [OSTI]

    Lin, Zhenhong; Ogden, Joan M; Fan, Yueyue; Sperling, Dan

    2006-01-01T23:59:59.000Z

    Zoia (2005). "Hydrogen infrastructure strategic planningITS—RR—06—05 The Hydrogen Infrastructure Transition Model (a 50-year Hydrogen Infrastructure for Urban Beijing Zhenhong

  13. A Mathematical Model for Predicting the Life of PEM Fuel Cell Membranes Subjected to Hydration Cycling

    E-Print Network [OSTI]

    Burlatsky, S F; O'Neill, J; Atrazhev, V V; Varyukhin, A N; Dmitriev, D V; Erikhman, N S

    2013-01-01T23:59:59.000Z

    Under typical PEM fuel cell operating conditions, part of membrane electrode assembly is subjected to humidity cycling due to variation of inlet gas RH and/or flow rate. Cyclic membrane hydration/dehydration would cause cyclic swelling/shrinking of the unconstrained membrane. In a constrained membrane, it causes cyclic stress resulting in mechanical failure in the area adjacent to the gas inlet. A mathematical modeling framework for prediction of the lifetime of a PEM FC membrane subjected to hydration cycling is developed in this paper. The model predicts membrane lifetime as a function of RH cycling amplitude and membrane mechanical properties. The modeling framework consists of three model components: a fuel cell RH distribution model, a hydration/dehydration induced stress model that predicts stress distribution in the membrane, and a damage accrual model that predicts membrane life-time. Short descriptions of the model components along with overall framework are presented in the paper. The model was used...

  14. Malthusian assumptions lead to Boserupian phenology in a global model of the transitions to agriculture

    E-Print Network [OSTI]

    Lemmen, Carsten

    2011-01-01T23:59:59.000Z

    In the many transitions from foraging to agropastoralism it is debated whether innovation in technology or increase of population is the primary driver. The driver discussion traditionally separates Malthusian (technology driven) from Boserupian (population driven) theories. I present a numerical model of the transition to agriculture and discuss this model in the light of the population versus technology debate and in Boserup's analytical frame- work in development theory. Although my model is based on ecological-Neomalthusian- principles, the coevolutionary positive feedback relationship between technology and population results in apparent Boserupian behaviour: innovation is greatest when population pressure is highest. This outcome is not only visible in the theory-driven reduced model, but is also present in a corresponding "real world" simulator which was tested against archaeological data, and which thus demonstrates the relevance and validity of the coevolutionary model. The lesson to be learned is th...

  15. Strongly anisotropic non-equilibrium phase transition in Ising models with friction

    E-Print Network [OSTI]

    Sebastian Angst; Alfred Hucht; Dietrich E. Wolf

    2012-05-22T23:59:59.000Z

    The non-equilibrium phase transition in driven two-dimensional Ising models with two different geometries is investigated using Monte Carlo methods as well as analytical calculations. The models show dissipation through fluctuation induced friction near the critical point. We first consider high driving velocities and demonstrate that both systems are in the same universality class and undergo a strongly anisotropic non-equilibrium phase transition, with anisotropy exponent \\theta=3. Within a field theoretical ansatz the simulation results are confirmed. The crossover from Ising to mean field behavior in dependency of system size and driving velocity is analyzed using crossover scaling. It turns out that for all finite velocities the phase transition becomes strongly anisotropic in the thermodynamic limit.

  16. A Model of Curvature-Induced Phase Transitions in Inflationary Universe

    E-Print Network [OSTI]

    J. Hashida; S. Mukaigawa; T. Muta; K. Ohkura; K. Yamamoto

    1998-12-21T23:59:59.000Z

    Chiral phase transitions driven by space-time curvature effects are investigated in de Sitter space in the supersymmetric Nambu-Jona-Lasinio model with soft supersymmetry breaking. The model is considered to be suitable for the analysis of possible phase transitions in inflationary universe. It is found that a restoration of the broken chiral symmetry takes place in two patterns for increasing curvature : the first order and second order phase transition respectively depending on initial settings of the four-body interaction parameter and the soft supersymmetry breaking parameter. The critical curves expressing the phase boundaries in these parameters are obtained. Cosmological implications of the result are discussed in connection with bubble formations and the creation of cosmic strings during the inflationary era.

  17. Phase transition in the spanning-hyperforest model on complete hypergraphs

    E-Print Network [OSTI]

    Bedini, Andrea; Sportiello, Andrea

    2009-01-01T23:59:59.000Z

    By using our novel Grassmann formulation we study the phase transition of the spanning-hyperforest model of the k-uniform complete hypergraph for any k>= 2. The case k=2 reduces to the spanning-forest model on the complete graph. Different k are studied at once by using a microcanonical ensemble in which the number of hyperforests is fixed. The low-temperature phase is characterized by the appearance of a giant hyperforest. The phase transition occurs when the number of hyperforests is a fraction (k-1)/k of the total number of vertices. The behaviour at criticality is also studied by means of the coalescence of two saddle points. As the Grassmann formulation exhibits a global supersymmetry we show that the phase transition is second order and is associated to supersymmetry breaking and we explore the pure thermodynamical phase at low temperature by introducing an explicit breaking field.

  18. Phase transition in the spanning-hyperforest model on complete hypergraphs

    E-Print Network [OSTI]

    Andrea Bedini; Sergio Caracciolo; Andrea Sportiello

    2009-06-24T23:59:59.000Z

    By using our novel Grassmann formulation we study the phase transition of the spanning-hyperforest model of the k-uniform complete hypergraph for any k>= 2. The case k=2 reduces to the spanning-forest model on the complete graph. Different k are studied at once by using a microcanonical ensemble in which the number of hyperforests is fixed. The low-temperature phase is characterized by the appearance of a giant hyperforest. The phase transition occurs when the number of hyperforests is a fraction (k-1)/k of the total number of vertices. The behaviour at criticality is also studied by means of the coalescence of two saddle points. As the Grassmann formulation exhibits a global supersymmetry we show that the phase transition is second order and is associated to supersymmetry breaking and we explore the pure thermodynamical phase at low temperature by introducing an explicit breaking field.

  19. Model for incorporating fuel swelling and clad shrinkage effects in diffusion theory calculations (LWBR Development Program)

    SciTech Connect (OSTI)

    Schick, W.C. Jr.; Milani, S.; Duncombe, E.

    1980-03-01T23:59:59.000Z

    A model has been devised for incorporating into the thermal feedback procedure of the PDQ few-group diffusion theory computer program the explicit calculation of depletion and temperature dependent fuel-rod shrinkage and swelling at each mesh point. The model determines the effect on reactivity of the change in hydrogen concentration caused by the variation in coolant channel area as the rods contract and expand. The calculation of fuel temperature, and hence of Doppler-broadened cross sections, is improved by correcting the heat transfer coefficient of the fuel-clad gap for the effects of clad creep, fuel densification and swelling, and release of fission-product gases into the gap. An approximate calculation of clad stress is also included in the model.

  20. Finite-temperature order-disorder phase transition in a cluster model of decagonal tilings

    E-Print Network [OSTI]

    Gähler, Franz

    phase,2 because its phason degrees of freedom are frozen (locked). The high-temperature state is accordingly called unlocked phase. Here, the thermal energy is suffi- ciently high to excite the phasonFinite-temperature order-disorder phase transition in a cluster model of decagonal tilings Michael

  1. Finitetemperature orderdisorder phase transition in a cluster model of decagonal tilings

    E-Print Network [OSTI]

    Gähler, Franz

    the locked phase, 2 because its phason degrees of freedom are frozen (locked). The high­temperature state is accordingly called unlocked phase. Here, the thermal energy is su#­ ciently high to excite the phason degreesFinite­temperature order­disorder phase transition in a cluster model of decagonal tilings Michael

  2. On a phase field model for solid-liquid phase transitions

    E-Print Network [OSTI]

    distinct phases. This is the case for solid-liquid mix- tures (e.g. ice-water or alloys duringOn a phase field model for solid-liquid phase transitions S. Benzoni-Gavage , L. Chupin , D. Jamet 3.2 Back to physical variables . . . . . . . . . . . . . . . . . . . . 16 4 Well-posedness 17 4

  3. Hybrid Car-Parrinello/Molecular Mechanics Modelling of Transition Metal Complexes: Structure, Dynamics and Reactivity

    E-Print Network [OSTI]

    Guidoni, Leonardo

    Hybrid Car-Parrinello/Molecular Mechanics Modelling of Transition Metal Complexes: Structure). We have recently developed a QM/MM extension of a Car-Parrinello scheme [5]. These hybrid Car functional theory embedded in a classical force field description. The power of such a combined Car

  4. Pseudo Dynamic Transitional Modeling of Building Heating Energy Demand Using Artificial1 Neural Network2

    E-Print Network [OSTI]

    Paris-Sud XI, Université de

    Transitional Modeling of Building Heating Energy Demand Using Artificial1 Neural Network2 Subodh Paudel a, it is39 essential to know energy flows and energy demand of the buildings for the control of heating and40 cooling energy production from plant systems. The energy demand of the building system, thus,41

  5. Model documentation, Renewable Fuels Module of the National Energy Modeling System

    SciTech Connect (OSTI)

    NONE

    1998-01-01T23:59:59.000Z

    This report documents the objectives, analytical approach, and design of the National Energy Modeling System (NEMS) Renewable Fuels Module (RFM) as it relates to the production of the Annual Energy Outlook 1998 (AEO98) forecasts. The report catalogues and describes modeling assumptions, computational methodologies, data inputs, and parameter estimation techniques. A number of offline analyses used in lieu of RFM modeling components are also described. For AEO98, the RFM was modified in three principal ways, introducing capital cost elasticities of supply for new renewable energy technologies, modifying biomass supply curves, and revising assumptions for use of landfill gas from municipal solid waste (MSW). In addition, the RFM was modified in general to accommodate projections beyond 2015 through 2020. Two supply elasticities were introduced, the first reflecting short-term (annual) cost increases from manufacturing, siting, and installation bottlenecks incurred under conditions of rapid growth, and the second reflecting longer term natural resource, transmission and distribution upgrade, and market limitations increasing costs as more and more of the overall resource is used. Biomass supply curves were also modified, basing forest products supplies on production rather than on inventory, and expanding energy crop estimates to include states west of the Mississippi River using information developed by the Oak Ridge National Laboratory. Finally, for MSW, several assumptions for the use of landfill gas were revised and extended.

  6. Radiolysis Model Sensitivity Analysis for a Used Fuel Storage Canister

    SciTech Connect (OSTI)

    Wittman, Richard S.

    2013-09-20T23:59:59.000Z

    This report fulfills the M3 milestone (M3FT-13PN0810027) to report on a radiolysis computer model analysis that estimates the generation of radiolytic products for a storage canister. The analysis considers radiolysis outside storage canister walls and within the canister fill gas over a possible 300-year lifetime. Previous work relied on estimates based directly on a water radiolysis G-value. This work also includes that effect with the addition of coupled kinetics for 111 reactions for 40 gas species to account for radiolytic-induced chemistry, which includes water recombination and reactions with air.

  7. Farshid Zabihian, Alan Fung A Review on Modeling of Hybrid Solid Oxide Fuel Cell Systems

    E-Print Network [OSTI]

    Farshid Zabihian; Alan Fung

    Over the past 2 decades, there has been tremendous progress on numerical and computational tools for fuel cells and energy systems based on them. The purpose of this work is to summarize the current status of hybrid solid oxide fuel cell (SOFC) cycles and identify areas that require further studies. In this review paper, a comprehensive literature survey on different types of SOFC hybrid systems modeling is presented. The paper has three parts. First, it describes the importance of the fuel cells modeling especially in SOFC hybrid cycles. Key features of the fuel cell models are highlighted and model selection criteria are explained. In the second part, the models in the open literature are categorized and discussed. It includes discussion on a detail example of SOFCgas turbine cycle model, description of early models, models with different objectives such as parametric analysis, comparison of configurations, exergy analysis, optimization, non-stationary power generation applications, transient and off-design analysis, thermoeconomic analysis and so on. Finally, in the last section, key features of selected models are summarized and suggestions for areas that require further studies are presented. In this paper, a hybrid cycle can be any combination of SOFC and gas turbine, steam turbine, coal integrated gasification, and application in combined heat and power cycle.

  8. TRANSIT TIMING OBSERVATIONS FROM KEPLER. V. TRANSIT TIMING VARIATION CANDIDATES IN THE FIRST SIXTEEN MONTHS FROM POLYNOMIAL MODELS

    SciTech Connect (OSTI)

    Ford, Eric B. [Astronomy Department, University of Florida, 211 Bryant Space Sciences Center, Gainesville, FL 32111 (United States); Ragozzine, Darin; Holman, Matthew J. [Harvard-Smithsonian Center for Astrophysics, 60 Garden Street, Cambridge, MA 02138 (United States); Rowe, Jason F.; Barclay, Thomas; Borucki, William J.; Bryson, Stephen T.; Caldwell, Douglas A.; Kinemuchi, Karen; Koch, David G.; Lissauer, Jack J.; Still, Martin; Tenenbaum, Peter [NASA Ames Research Center, Moffett Field, CA 94035 (United States); Steffen, Jason H. [Fermilab Center for Particle Astrophysics, P.O. Box 500, MS 127, Batavia, IL 60510 (United States); Batalha, Natalie M. [Department of Physics and Astronomy, San Jose State University, San Jose, CA 95192 (United States); Fabrycky, Daniel C. [UCO/Lick Observatory, University of California, Santa Cruz, CA 95064 (United States); Gautier, Thomas N. [Jet Propulsion Laboratory/California Institute of Technology, Pasadena, CA 91109 (United States); Ibrahim, Khadeejah A.; Uddin, Kamal [Orbital Sciences Corporation/NASA Ames Research Center, Moffett Field, CA 94035 (United States); Kjeldsen, Hans, E-mail: eford@astro.ufl.edu [Department of Physics and Astronomy, Aarhus University, DK-8000 Aarhus C (Denmark); and others

    2012-09-10T23:59:59.000Z

    Transit timing variations provide a powerful tool for confirming and characterizing transiting planets, as well as detecting non-transiting planets. We report the results of an updated transit timing variation (TTV) analysis for 1481 planet candidates based on transit times measured during the first sixteen months of Kepler observations. We present 39 strong TTV candidates based on long-term trends (2.8% of suitable data sets). We present another 136 weaker TTV candidates (9.8% of suitable data sets) based on the excess scatter of TTV measurements about a linear ephemeris. We anticipate that several of these planet candidates could be confirmed and perhaps characterized with more detailed TTV analyses using publicly available Kepler observations. For many others, Kepler has observed a long-term TTV trend, but an extended Kepler mission will be required to characterize the system via TTVs. We find that the occurrence rate of planet candidates that show TTVs is significantly increased ({approx}68%) for planet candidates transiting stars with multiple transiting planet candidates when compared to planet candidates transiting stars with a single transiting planet candidate.

  9. 2D Axisymmetric Coupled CFD-kinetics Modeling of a Nonthermal Arc Plasma Torch for Diesel Fuel

    E-Print Network [OSTI]

    Boyer, Edmond

    1 2D Axisymmetric Coupled CFD-kinetics Modeling of a Nonthermal Arc Plasma Torch for Diesel Fuel-assisted diesel fuel reformer developed for two different applications: (i) onboard H2 production for fuel cell. In the first case, diesel fuel reacts with air while in the second case it reacts with diesel engine exhaust

  10. The Modeling of a Standalone Solid-Oxide Fuel Cell Auxiliary Power Unit

    SciTech Connect (OSTI)

    Lu, Ning; Li, Qinghe; Sun, Xin; Khaleel, Mohammad A.

    2006-10-27T23:59:59.000Z

    In this research, a Simulink model of a standalone vehicular solid-oxide fuel cell (SOFC) auxiliary power unit (APU) is developed. The SOFC APU model consists of three major components: a controller model; a power electronics system model; and an SOFC plant model, including an SOFC stack module; two heat exchanger modules; and a combustor module. This paper discusses the development of the nonlinear dynamic models for the SOFC stacks, the heat exchangers and the combustors. When coupling with a controller model and a power electronic circuit model, the developed SOFC plant model is able to model the thermal dynamics and the electrochemical dynamics inside the SOFC APU components as well as the transient responses to the electric loading changes. It has been shown that having such a model for the SOFC APU will benefit design engineers to adjust design parameters to optimize the performance. The modeling results of the heat-up stage of an SOFC APU and the output voltage response to a sudden load change are presented in the paper. The fuel flow regulation based on fuel utilization is also briefly discussed.

  11. Dynamic modeling of physical phenomena for probabilistic assessment of spent fuel accidents

    SciTech Connect (OSTI)

    Benjamin, A.S.

    1997-11-01T23:59:59.000Z

    If there should be an accident involving drainage of all the water from a spent fuel pool, the fuel elements will heat up until the heat produced by radioactive decay is balanced by that removed by natural convection to air, thermal radiation, and other means. If the temperatures become high enough for the cladding or other materials to ignite due to rapid oxidation, then some of the fuel might melt, leading to an undesirable release of radioactive materials. The amount of melting is dependent upon the fuel loading configuration and its age, the oxidation and melting characteristics of the materials, and the potential effectiveness of recovery actions. The authors have developed methods for modeling the pertinent physical phenomena and integrating the results with a probabilistic treatment of the uncertainty distributions. The net result is a set of complementary cumulative distribution functions for the amount of fuel melted.

  12. A thermodynamically consistent Ginzburg-Landau model for superfluid transition in liquid helium

    E-Print Network [OSTI]

    Alessia Berti; Valeria Berti

    2012-11-15T23:59:59.000Z

    In this paper we propose a thermodynamically consistent model for superfluid-normal phase transition in liquid helium, accounting for variations of temperature and density. The phase transition is described by means of an order parameter, according to the Ginzburg-Landau theory, emphasizing the analogies between superfluidity and superconductivity. The normal component of the velocity is assumed to be compressible and the usual phase diagram of liquid helium is recovered. Moreover, the continuity equation leads to a dependence between density and temperature in agreement with the experimental data.

  13. Proceedings of the 2007 Aging Aircraft Conference Cost Model for Assessing the Transition to Lead-Free Electronics

    E-Print Network [OSTI]

    Sandborn, Peter

    Proceedings of the 2007 Aging Aircraft Conference Cost Model for Assessing the Transition to Lead the cost ramifications of the transition from tin- lead to lead-free electronic parts. All tin-lead, all lead-free and mixed assembly approaches are considered. The model makes basic assumptions of a fixed

  14. Phase transitions in self-gravitating systems. Self-gravitating fermions and hard spheres models

    E-Print Network [OSTI]

    P. H. Chavanis

    2002-01-28T23:59:59.000Z

    We discuss the nature of phase transitions in self-gravitating systems both in the microcanonical and in the canonical ensemble. We avoid the divergence of the gravitational potential at short distances by considering the case of self-gravitating fermions and hard spheres models. Three kinds of phase transitions (of zeroth, first and second order) are evidenced. They separate a ``gaseous'' phase with a smoothly varying distribution of matter from a ``condensed'' phase with a core-halo structure. We propose a simple analytical model to describe these phase transitions. We determine the value of energy (in the microcanonical ensemble) and temperature (in the canonical ensemble) at the transition point and we study their dependance with the degeneracy parameter (for fermions) or with the size of the particles (for a hard spheres gas). Scaling laws are obtained analytically in the asymptotic limit of a small short distance cut-off. Our analytical model captures the essential physics of the problem and compares remarkably well with the full numerical solutions.

  15. Development and validation of a two-phase, three-dimensional model for PEM fuel cells.

    SciTech Connect (OSTI)

    Chen, Ken Shuang

    2010-04-01T23:59:59.000Z

    The objectives of this presentation are: (1) To develop and validate a two-phase, three-dimensional transport modelfor simulating PEM fuel cell performance under a wide range of operating conditions; (2) To apply the validated PEM fuel cell model to improve fundamental understanding of key phenomena involved and to identify rate-limiting steps and develop recommendations for improvements so as to accelerate the commercialization of fuel cell technology; (3) The validated PEMFC model can be employed to improve and optimize PEM fuel cell operation. Consequently, the project helps: (i) address the technical barriers on performance, cost, and durability; and (ii) achieve DOE's near-term technical targets on performance, cost, and durability in automotive and stationary applications.

  16. THETRIS: A MICRO-SCALE TEMPERATURE AND GAS RELEASE MODEL FOR TRISO FUEL

    SciTech Connect (OSTI)

    J. Ortensi; A.M. Ougouag

    2011-12-01T23:59:59.000Z

    The dominating mechanism in the passive safety of gas-cooled, graphite-moderated, high-temperature reactors (HTRs) is the Doppler feedback effect. These reactor designs are fueled with sub-millimeter sized kernels formed into TRISO particles that are imbedded in a graphite matrix. The best spatial and temporal representation of the feedback effect is obtained from an accurate approximation of the fuel temperature. Most accident scenarios in HTRs are characterized by large time constants and slow changes in the fuel and moderator temperature fields. In these situations a meso-scale, pebble and compact scale, solution provides a good approximation of the fuel temperature. Micro-scale models are necessary in order to obtain accurate predictions in faster transients or when parameters internal to the TRISO are needed. Since these coated particles constitute one of the fundamental design barriers for the release of fission products, it becomes important to understand the transient behavior inside this containment system. An explicit TRISO fuel temperature model named THETRIS has been developed and incorporated into the CYNOD-THERMIX-KONVEK suite of coupled codes. The code includes gas release models that provide a simple predictive capability of the internal pressure during transients. The new model yields similar results to those obtained with other micro-scale fuel models, but with the added capability to analyze gas release, internal pressure buildup, and effects of a gap in the TRISO. The analyses show the instances when the micro-scale models improve the predictions of the fuel temperature and Doppler feedback. In addition, a sensitivity study of the potential effects on the transient behavior of high-temperature reactors due to the presence of a gap is included. Although the formation of a gap occurs under special conditions, its consequences on the dynamic behavior of the reactor can cause unexpected responses during fast transients. Nevertheless, the strong Doppler feedback forces the reactor to quickly stabilize.

  17. Statistic inversion of multi-zone transition probability models for aquifer characterization in alluvial fans

    E-Print Network [OSTI]

    Zhu, Lin; Gong, Huili; Gable, Carl; Teatini, Pietro

    2015-01-01T23:59:59.000Z

    Understanding the heterogeneity arising from the complex architecture of sedimentary sequences in alluvial fans is challenging. This paper develops a statistical inverse framework in a multi-zone transition probability approach for characterizing the heterogeneity in alluvial fans. An analytical solution of the transition probability matrix is used to define the statistical relationships among different hydrofacies and their mean lengths, integral scales, and volumetric proportions. A statistical inversion is conducted to identify the multi-zone transition probability models and estimate the optimal statistical parameters using the modified Gauss-Newton-Levenberg-Marquardt method. The Jacobian matrix is computed by the sensitivity equation method, which results in an accurate inverse solution with quantification of parameter uncertainty. We use the Chaobai River alluvial fan in the Beijing Plain, China, as an example for elucidating the methodology of alluvial fan characterization. The alluvial fan is divided...

  18. Modeling the Integrated Performance of Dispersion and Monolithic U-Mo Based Fuels

    SciTech Connect (OSTI)

    Daniel M. Wachs; Douglas E. Burkes; Steven L. Hayes; Karen Moore; Greg Miller; Gerard Hofman; Yeon Soo Kim

    2006-10-01T23:59:59.000Z

    The evaluation and prediction of integrated fuel performance is a critical component of the Reduced Enrichment for Research and Test Reactors (RERTR) program. The PLATE code is the primary tool being developed and used to perform these functions. The code is being modified to incorporate the most recent fuel/matrix interaction correlations as they become available for both aluminum and aluminum/silicon matrices. The code is also being adapted to treat cylindrical and square pin geometries to enhance the validation database by including the results gathered from various international partners. Additional modeling work has been initiated to evaluate the thermal and mechanical performance requirements unique to monolithic fuels during irradiation.

  19. Modeling and Analysis of UN TRISO Fuel for LWR Application Using the PARFUME Code

    SciTech Connect (OSTI)

    Blaise Collin

    2014-08-01T23:59:59.000Z

    The Idaho National Laboraroty (INL) PARFUME (particle fuel model) code was used to assess the overall fuel performance of uranium nitride (UN) tristructural isotropic (TRISO) ceramic fuel under irradiation conditions typical of a Light Water Reactor (LWR). The dimensional changes of the fuel particle layers and kernel were calculated, including the formation of an internal gap. The survivability of the UN TRISO particle was estimated depending on the strain behavior of the constituent materials at high fast fluence and burn up. For nominal cases, internal gas pressure and representative thermal profiles across the kernel and layers were determined along with stress levels in the inner and outer pyrolytic carbon (IPyC/OPyC) and silicon carbide (SiC) layers. These parameters were then used to evaluate fuel particle failure probabilities. Results of the study show that the survivability of UN TRISO fuel under LWR irradiation conditions might only be guaranteed if the kernel and PyC swelling rates are limited at high fast fluence and burn up. These material properties have large uncertainties at the irradiation levels expected to be reached by UN TRISO fuel in LWRs. Therefore, a large experimental effort would be needed to establish material properties, including kernel and PyC swelling rates, under these conditions before definitive conclusions can be drawn on the behavior of UN TRISO fuel in LWRs.

  20. QCD Phase Transition in Brans-Dicke DGP model of Brane Gravity

    E-Print Network [OSTI]

    T. Golanbari; A. Mohammadi; Kh. Saaidi

    2014-08-24T23:59:59.000Z

    A DGP brane-world model with a perfect fluid brane matter including a Brans-Dicke (BD) scalar field on brane has been utilized to investigate the problem of quark-hadron phase (QHP) transition in early times of the Universe evoltion. The presence of BD scalar field came up with some modification terms in the Friedmann equation, however we have a usual form of conservation equation for brane matter since scalar field only has a non-mnimally interaction with geometry. Behavior of phase transition strongly depends on the basic evolution equations. Then, even a small change in these relation might come to interesting results about the time of transition. Two different formalisms as smooth crossover formalism in which lattice QCD data is used for obtaining the matter equation of state and first-order phase transition formalism, have been used to investigate of the evolution of physical quatities relevant to quantitative of early times such as energy density $\\rho$, scale factor $a$, and temperature $T$. The obtained results show that the general behavior of temperature is similar in both of two formalisms and the QHP transition occurred at about micro-second after the Big Bang.

  1. Detailed Chemical Kinetic Modeling of Surrogate Fuels for Gasoline and Application to an HCCI Engine

    SciTech Connect (OSTI)

    Naik, C V; Pitz, W J; Sj?berg, M; Dec, J E; Orme, J; Curran, H J; Simmie, J M; Westbrook, C K

    2005-01-07T23:59:59.000Z

    Gasoline consists of many different classes of hydrocarbons, such as paraffins, olefins, aromatics, and cycloalkanes. In this study, a surrogate gasoline reaction mechanism is developed, and it has one representative fuel constituent from each of these classes. These selected constituents are iso-octane, n-heptane, 1-pentene, toluene, and methyl-cyclohexane. The mechanism was developed in a step-wise fashion, adding submechanisms to treat each fuel component. Reactions important for low temperature oxidation (<1000K) and cross-reactions among different fuels are incorporated into the mechanism. The mechanism consists of 1214 species and 5401 reactions. A single-zone engine model is used to evaluate how well the mechanism captures autoignition behavior for conditions corresponding to homogeneous charge compression ignition (HCCI) engine operation. Experimental data are available for both how the combustion phasing changes with fueling at a constant intake temperature, and also how the intake temperature has to be changed with pressure in order to maintain combustion phasing for a fixed equivalence ratio. Three different surrogate fuel mixtures are used for the modeling. Predictions are in reasonably good agreement with the engine data. In addition, the heat release rate is calculated and compared to the data from experiments. The model predicts less low-temperature heat release than that measured. It is found that the low temperature heat-release rate depends strongly on engine speed, reactions of RO{sub 2}+HO{sub 2}, fuel composition, and pressure boost.

  2. Experimental and Modeling Study of the Flammability of Fuel Tank Headspace Vapors from High Ethanol Content Fuels

    SciTech Connect (OSTI)

    Gardiner, D.; Bardon, M.; Pucher, G.

    2008-10-01T23:59:59.000Z

    Study determined the flammability of fuel tank headspace vapors as a function of ambient temperature for seven E85 fuel blends, two types of gasoline, and denatured ethanol at a low tank fill level.

  3. Journal of Power Sources 162 (2006) 388399 Model-based condition monitoring of PEM fuel cell using

    E-Print Network [OSTI]

    Ding, Yu

    2006-01-01T23:59:59.000Z

    Journal of Power Sources 162 (2006) 388­399 Model-based condition monitoring of PEM fuel cell using of polymer electrolyte membrane (PEM) fuel cell systems, temporary faults in such systems still might occur/uncertainty of the fuel cell system, and the measurement noise. In this research, we propose a model-based condition

  4. Modeling and Control for PEM Fuel Cell Stack System I Jay T. Pukrushpan, Anna G. Stefanopoulou, Huei Peng

    E-Print Network [OSTI]

    Peng, Huei

    Modeling and Control for PEM Fuel Cell Stack System I Jay T. Pukrushpan, Anna G. Stefanopoulou~umich, edu, hpeng@umich, edu Abstract A nonlinear fuel cell system dynamic model that is suit- able, the reactant partial pres- sures. Characterization of the Fuel Cell polarization curves based on time varying

  5. A Two Transition State Model for Radical-Molecule Reactions: A Case Study of the Addition of OH to C2H4

    E-Print Network [OSTI]

    North, Simon W.

    A Two Transition State Model for Radical-Molecule Reactions: A Case Study of the Addition of OH; In Final Form: April 6, 2005 A two transition state model is applied to the study of the addition of both inner and outer transition states. The outer transition state is treated with a recently derived

  6. A NEW APPROACH TO MODELING LARGE-SCALE ALTERNATIVE FUEL AND VEHICLE TRANSITIONS

    E-Print Network [OSTI]

    Lin, C.-Y. Cynthia

    including electricity, hydrogen, and biofuels will have to achieve mass-market acceptance and capacity along

  7. Fire Behavior Modeling - Experiment on Surface Fire Transition to the Elevated Live Fuel

    E-Print Network [OSTI]

    Omodan, Sunday

    2015-01-01T23:59:59.000Z

    energy conductivity, turbulent kinetic energy L flame height m massgrid size viscous dissipation energy absorption coefficient

  8. Experimental and Modeling Study of the Flammability of Fuel Tank Headspace Vapors from Ethanol/Gasoline Fuels, Phase 2: Evaluations of Field Samples and Laboratory Blends

    SciTech Connect (OSTI)

    Gardiner, D. P.; Bardon, M. F.; LaViolette, M.

    2010-04-01T23:59:59.000Z

    Study to measure the flammability of gasoline/ethanol fuel vapors at low ambient temperatures and develop a mathematical model to predict temperatures at which flammable vapors were likely to form.

  9. TRISO Fuel Performance: Modeling, Integration into Mainstream Design Studies, and Application to a Thorium-fueled Fusion-Fission Hybrid Blanket

    E-Print Network [OSTI]

    Powers, Jeffrey

    2011-01-01T23:59:59.000Z

    Neutronics Models and Methodologies 3.1 Thorium LIFE DesignEngine. . .Design Parameters for Thorium-fueled LIFE TRISOburnup value for DU and Thorium hybrid LIFE engine designs

  10. Autoignition of toluene reference fuels at high pressures modeled with detailed chemical kinetics

    SciTech Connect (OSTI)

    Andrae, J.C.G. [Department of Chemical Engineering and Technology, Royal Institute of Technology, SE-100 44 Stockholm (Sweden); Shell Global Solutions, P.O. Box 1, Chester CH1 3SH (United Kingdom); Bjoernbom, P. [Department of Chemical Engineering and Technology, Royal Institute of Technology, SE-100 44 Stockholm (Sweden); Cracknell, R.F.; Kalghatgi, G.T. [Shell Global Solutions, P.O. Box 1, Chester CH1 3SH (United Kingdom)

    2007-04-15T23:59:59.000Z

    A detailed chemical kinetic model for the autoignition of toluene reference fuels (TRF) is presented. The toluene submechanism added to the Lawrence Livermore Primary Reference Fuel (PRF) mechanism was developed using recent shock tube autoignition delay time data under conditions relevant to HCCI combustion. For two-component fuels the model was validated against recent high-pressure shock tube autoignition delay time data for a mixture consisting of 35% n-heptane and 65% toluene by liquid volume. Important features of the autoignition of the mixture proved to be cross-acceleration effects, where hydroperoxy radicals produced during n-heptane oxidation dramatically increased the oxidation rate of toluene compared to the case when toluene alone was oxidized. Rate constants for the reaction of benzyl and hydroperoxyl radicals previously used in the modeling of the oxidation of toluene alone were untenably high for modeling of the mixture. To model both systems it was found necessary to use a lower rate and introduce an additional branching route in the reaction between benzyl radicals and O{sub 2}. Good agreement between experiments and predictions was found when the model was validated against shock tube autoignition delay data for gasoline surrogate fuels consisting of mixtures of 63-69% isooctane, 14-20% toluene, and 17% n-heptane by liquid volume. Cross reactions such as hydrogen abstractions between toluene and alkyl and alkylperoxy radicals and between the PRF were introduced for completion of chemical description. They were only of small importance for modeling autoignition delays from shock tube experiments, even at low temperatures. A single-zone engine model was used to evaluate how well the validated mechanism could capture autoignition behavior of toluene reference fuels in a homogeneous charge compression ignition (HCCI) engine. The model could qualitatively predict the experiments, except in the case with boosted intake pressure, where the initial temperature had to be increased significantly in order to predict the point of autoignition. (author)

  11. Benchmarking of the MIT High Temperature Gas-cooled Reactor TRISO-coated particle fuel performance model

    E-Print Network [OSTI]

    Stawicki, Michael A

    2006-01-01T23:59:59.000Z

    MIT has developed a Coated Particle Fuel Performance Model to study the behavior of TRISO nuclear fuels. The code, TIMCOAT, is designed to assess the mechanical and chemical condition of populations of coated particles and ...

  12. Two dimensional, two fluid model for sodium boiling in LMFBR fuel assemblies

    SciTech Connect (OSTI)

    Granziera, M.R.; Kazimi, M.S.

    1980-05-01T23:59:59.000Z

    A two dimensional numerical model for the simulation of sodium boiling transient was developed using the two fluid set of conservation equations. A semiimplicit numerical differencing scheme capable of handling the problems associated with the ill-posedness implied by the complex characteristic roots of the two fluid problems was used, which took advantage of the dumping effect of the exchange terms. Of particular interest in the development of the model was the identification of the numerical problems caused by the strong disparity between the axial and radial dimensions of fuel assemblies. A solution to this problem was found which uses the particular geometry of fuel assemblies to accelerate the convergence of the iterative technique used in the model. Three sodium boiling experiments were simulated with the model, with good agreement between the experimental results and the model predictions.

  13. Modeling the Oil Transition: A Summary of the Proceedings of the DOE/EPA Workshop on the Economic and Environmental Implications of Global Energy Transitions

    SciTech Connect (OSTI)

    Greene, David L [ORNL

    2007-02-01T23:59:59.000Z

    The global energy system faces sweeping changes in the next few decades, with potentially critical implications for the global economy and the global environment. It is important that global institutions have the tools necessary to predict, analyze and plan for such massive change. This report summarizes the proceedings of an international workshop concerning methods of forecasting, analyzing, and planning for global energy transitions and their economic and environmental consequences. A specific case, it focused on the transition from conventional to unconventional oil and other energy sources likely to result from a peak in non-OPEC and/or global production of conventional oil. Leading energy models from around the world in government, academia and the private sector met, reviewed the state-of-the-art of global energy modeling and evaluated its ability to analyze and predict large-scale energy transitions.

  14. Control-relevant Modelling and Linear Analysis of Instabilities in Oxy-fuel Combustion

    E-Print Network [OSTI]

    Foss, Bjarne A.

    Control-relevant Modelling and Linear Analysis of Instabilities in Oxy-fuel Combustion Dagfinn combustion have been proposed as an alternative to conventional gas turbine cycles for achieving CO2-capture for CO2 sequestration purposes. While combustion instabilities is a problem in modern conventional gas

  15. A combustion model for IC engine combustion simulations with multi-component fuels

    SciTech Connect (OSTI)

    Ra, Youngchul; Reitz, Rolf D. [Engine Research Center, University of Wisconsin-Madison (United States)

    2011-01-15T23:59:59.000Z

    Reduced chemical kinetic mechanisms for the oxidation of representative surrogate components of a typical multi-component automotive fuel have been developed and applied to model internal combustion engines. Starting from an existing reduced mechanism for primary reference fuel (PRF) oxidation, further improvement was made by including additional reactions and by optimizing reaction rate constants of selected reactions. Using a similar approach to that used to develop the reduced PRF mechanism, reduced mechanisms for the oxidation of n-tetradecane, toluene, cyclohexane, dimethyl ether (DME), ethanol, and methyl butanoate (MB) were built and combined with the PRF mechanism to form a multi-surrogate fuel chemistry (MultiChem) mechanism. The final version of the MultiChem mechanism consists of 113 species and 487 reactions. Validation of the present MultiChem mechanism was performed with ignition delay time measurements from shock tube tests and predictions by comprehensive mechanisms available in the literature. A combustion model was developed to simulate engine combustion with multi-component fuels using the present MultiChem mechanism, and the model was applied to simulate HCCI and DI engine combustion. The results show that the present multi-component combustion model gives reliable performance for combustion predictions, as well as computational efficiency improvements through the use of reduced mechanism for multi-dimensional CFD simulations. (author)

  16. MULTIPLE ARX MODEL-BASED AIR-FUEL RATIO PREDICTIVE CONTROL FOR SI

    E-Print Network [OSTI]

    Johansen, Tor Arne

    strategy for combustion engines. The mix- ture quality is essential for efficiency of a three- way control problems. One of the most popular approaches to combustion engine modeling is based on neural where the amount of the fuel is a function of the control action. It was demonstrated by simulation

  17. System Design Description and Requirements for Modeling the Off-Gas Systems for Fuel Recycling Facilities

    SciTech Connect (OSTI)

    Daryl R. Haefner; Jack D. Law; Troy J. Tranter

    2010-08-01T23:59:59.000Z

    This document provides descriptions of the off-gases evolved during spent nuclear fuel processing and the systems used to capture the gases of concern. Two reprocessing techniques are discussed, namely aqueous separations and electrochemical (pyrochemical) processing. The unit operations associated with each process are described in enough detail so that computer models to mimic their behavior can be developed. The document also lists the general requirements for the desired computer models.

  18. Formulation, Implementation and Validation of a Two-Fluid model in a Fuel Cell CFD Code

    SciTech Connect (OSTI)

    Kunal Jain, Vernon Cole, Sanjiv Kumar and N. Vaidya

    2008-11-01T23:59:59.000Z

    Water management is one of the main challenges in PEM Fuel Cells. While water is essential for membrane electrical conductivity, excess liquid water leads to ooding of catalyst layers. Despite the fact that accurate prediction of two-phase transport is key for optimal water management, understanding of the two-phase transport in fuel cells is relatively poor. Wang et. al. [1], [2] have studied the two-phase transport in the channel and diffusion layer separately using a multiphase mixture model. The model fails to accurately predict saturation values for high humidity inlet streams. Nguyen et. al. [3] developed a two-dimensional, two-phase, isothermal, isobaric, steady state model of the catalyst and gas diffusion layers. The model neglects any liquid in the channel. Djilali et. al. [4] developed a three-dimensional two-phase multicomponent model. The model is an improvement over previous models, but neglects drag between the liquid and the gas phases in the channel. In this work, we present a comprehensive two- fluid model relevant to fuel cells. Models for two-phase transport through Channel, Gas Diffusion Layer (GDL) and Channel-GDL interface, are discussed. In the channel, the gas and liquid pressures are assumed to be same. The surface tension effects in the channel are incorporated using the continuum surface force (CSF) model. The force at the surface is expressed as a volumetric body force and added as a source to the momentum equation. In the GDL, the gas and liquid are assumed to be at different pressures. The difference in the pressures (capillary pressure) is calculated using an empirical correlations. At the Channel-GDL interface, the wall adhesion affects need to be taken into account. SIMPLE-type methods recast the continuity equation into a pressure-correction equation, the solution of which then provides corrections for velocities and pressures. However, in the two-fluid model, the presence of two phasic continuity equations gives more freedom and more complications. A general approach would be to form a mixture continuity equation by linearly combining the phasic continuity equations using appropriate weighting factors. Analogous to mixture equation for pressure correction, a difference equation is used for the volume/phase fraction by taking the difference between the phasic continuity equations. The relative advantages of the above mentioned algorithmic variants for computing pressure correction and volume fractions are discussed and quantitatively assessed. Preliminary model validation is done for each component of the fuel cell. The two-phase transport in the channel is validated using empirical correlations. Transport in the GDL is validated against results obtained from LBM and VOF simulation techniques. The Channel-GDL interface transport will be validated against experiment and empirical correlation of droplet detachment at the interface. References [1] Y. Wang S. Basu and C.Y. Wang. Modeling two-phase flow in pem fuel cell channels. J. Power Sources, 179:603{617, 2008. [2] P. K. Sinha and C. Y. Wang. Liquid water transport in a mixed-wet gas diffusion layer of a polymer electrolyte fuel cell. Chem. Eng. Sci., 63:1081-1091, 2008. [3] Guangyu Lin and Trung Van Nguyen. A two-dimensional two-phase model of a pem fuel cell. J. Electrochem. Soc., 153(2):A372{A382, 2006. [4] T. Berning and N. Djilali. A 3d, multiphase, multicomponent model of the cathode and anode of a pem fuel cell. J. Electrochem. Soc., 150(12):A1589{A1598, 2003.

  19. REACTOR PHYSICS MODELING OF SPENT RESEARCH REACTOR FUEL FOR TECHNICAL NUCLEAR FORENSICS

    SciTech Connect (OSTI)

    Nichols, T.; Beals, D.; Sternat, M.

    2011-07-18T23:59:59.000Z

    Technical nuclear forensics (TNF) refers to the collection, analysis and evaluation of pre- and post-detonation radiological or nuclear materials, devices, and/or debris. TNF is an integral component, complementing traditional forensics and investigative work, to help enable the attribution of discovered radiological or nuclear material. Research is needed to improve the capabilities of TNF. One research area of interest is determining the isotopic signatures of research reactors. Research reactors are a potential source of both radiological and nuclear material. Research reactors are often the least safeguarded type of reactor; they vary greatly in size, fuel type, enrichment, power, and burn-up. Many research reactors are fueled with highly-enriched uranium (HEU), up to {approx}93% {sup 235}U, which could potentially be used as weapons material. All of them have significant amounts of radiological material with which a radioactive dispersal device (RDD) could be built. Therefore, the ability to attribute if material originated from or was produced in a specific research reactor is an important tool in providing for the security of the United States. Currently there are approximately 237 operating research reactors worldwide, another 12 are in temporary shutdown and 224 research reactors are reported as shut down. Little is currently known about the isotopic signatures of spent research reactor fuel. An effort is underway at Savannah River National Laboratory (SRNL) to analyze spent research reactor fuel to determine these signatures. Computer models, using reactor physics codes, are being compared to the measured analytes in the spent fuel. This allows for improving the reactor physics codes in modeling research reactors for the purpose of nuclear forensics. Currently the Oak Ridge Research reactor (ORR) is being modeled and fuel samples are being analyzed for comparison. Samples of an ORR spent fuel assembly were taken by SRNL for analytical and radiochemical analysis. The fuel assembly was modeled using MONTEBURNS(MCNP5/ ORIGEN2.2) and MCNPX/CINDER90. The results from the models have been compared to each other and to the measured data.

  20. Regional refining models for alternative fuels using shale and coal synthetic crudes: identification and evaluation of optimized alternative fuels. Annual report, March 20, 1979-March 19, 1980

    SciTech Connect (OSTI)

    Sefer, N.R.; Russell, J.A.

    1980-11-01T23:59:59.000Z

    The initial phase has been completed in the project to evaluate alternative fuels for highway transportation from synthetic crudes. Three refinery models were developed for Rocky Mountain, Mid-Continent and Great Lakes regions to make future product volumes and qualities forecast for 1995. Projected quantities of shale oil and coal oil syncrudes were introduced into the raw materials slate. Product slate was then varied from conventional products to evaluate maximum diesel fuel and broadcut fuel in all regions. Gasoline supplement options were evaluated in one region for 10% each of methanol, ethanol, MTBE or synthetic naphtha in the blends along with syncrude components. Compositions and qualities of the fuels were determined for the variation in constraints and conditions established for the study. Effects on raw materials, energy consumption and investment costs were reported. Results provide the basis to formulate fuels for laboratory and engine evaluation in future phases of the project.

  1. Summary report on the fuel performance modeling of the AFC-2A, 2B irradiation experiments

    SciTech Connect (OSTI)

    Pavel G. Medvedev

    2013-09-01T23:59:59.000Z

    The primary objective of this work at the Idaho National Laboratory (INL) is to determine the fuel and cladding temperature history during irradiation of the AFC-2A, 2B transmutation metallic fuel alloy irradiation experiments containing transuranic and rare earth elements. Addition of the rare earth elements intends to simulate potential fission product carry-over from pyro-metallurgical reprocessing. Post irradiation examination of the AFC-2A, 2B rodlets revealed breaches in the rodlets and fuel melting which was attributed to the release of the fission gas into the helium gap between the rodlet cladding and the capsule which houses six individually encapsulated rodlets. This release is not anticipated during nominal operation of the AFC irradiation vehicle that features a double encapsulated design in which sodium bonded metallic fuel is separated from the ATR coolant by the cladding and the capsule walls. The modeling effort is focused on assessing effects of this unanticipated event on the fuel and cladding temperature with an objective to compare calculated results with the temperature limits of the fuel and the cladding.

  2. Uncertainty and sensitivity analysis of fission gas behavior in engineering-scale fuel modeling

    SciTech Connect (OSTI)

    G. Pastore; L.P. Swiler; J.D. Hales; S.R. Novascone; D.M. Perez; B.W. Spencer; L. Luzzi; P. Van Uffelen; R.L. Williamson

    2014-10-01T23:59:59.000Z

    The role of uncertainties in fission gas behavior calculations as part of engineering-scale nuclear fuel modeling is investigated using the BISON fuel performance code and a recently implemented physics-based model for the coupled fission gas release and swelling. Through the integration of BISON with the DAKOTA software, a sensitivity analysis of the results to selected model parameters is carried out based on UO2 single-pellet simulations covering different power regimes. The parameters are varied within ranges representative of the relative uncertainties and consistent with the information from the open literature. The study leads to an initial quantitative assessment of the uncertainty in fission gas behavior modeling with the parameter characterization presently available. Also, the relative importance of the single parameters is evaluated. Moreover, a sensitivity analysis is carried out based on simulations of a fuel rod irradiation experiment, pointing out a significant impact of the considered uncertainties on the calculated fission gas release and cladding diametral strain. The results of the study indicate that the commonly accepted deviation between calculated and measured fission gas release by a factor of 2 approximately corresponds to the inherent modeling uncertainty at high fission gas release. Nevertheless, higher deviations may be expected for values around 10% and lower. Implications are discussed in terms of directions of research for the improved modeling of fission gas behavior for engineering purposes.

  3. Fuel-Specific Effect of Exhaust Gas Residuals on HCCI Combustion: A Modeling Study

    SciTech Connect (OSTI)

    Szybist, James P [ORNL

    2008-01-01T23:59:59.000Z

    A modeling study was performed to investigate fuel-specific effects of exhaust gas recirculation (EGR) components on homogeneous charge compression ignition (HCCI) combustion at conditions relevant to the negative valve overlap (NVO) strategy using CHEMKIN-PRO. Four single-component fuels with well-established kinetic models were chosen: n-heptane, iso-octane, ethanol, and toluene. These fuels were chosen because they span a wide range of fuel chemistries, and produce a wide compositions range of complete stoichiometric products (CSP). The simulated engine conditions combined a typical spark ignition engine compression ratio (11.34) and high intake charge temperatures (500-550 K) that are relevant to NVO HCCI. It was found that over the conditions investigated, all the fuels had overlapping start of combustion (SOC) phasing, despite the wide range in octane number (RON = 0 to 120). The effect of the EGR components CO2 and H2O was to suppress the compression temperature because of their higher heat capacities, which retarded SOC. For a concentration of O2 higher than the stoichiometric amount, or excess O2, there was an effect of advancing SOC for n-heptane, iso-octane, and toluene, but SOC for ethanol was not advanced. Low temperature heat release (LTHR) for n-heptane was also found to be highly dependent on excess O2, and mild endothermic reaction was observed for cases when excess O2 was not present.

  4. A comparison of geospatially modeled fire behavior and potential application to fire and fuels management for the Savannah River Site.

    SciTech Connect (OSTI)

    Kurth, Laurie; Hollingsworth, LaWen; Shea, Dan

    2011-12-20T23:59:59.000Z

    This study evaluates modeled fire behavior for the Savannah River Site in the Atlantic Coastal Plain of the southeastern U.S. using three data sources: FCCS, LANDFIRE, and SWRA. The Fuel Characteristic Classification System (FCCS) was used to build fuelbeds from intensive field sampling of 629 plots. Custom fire behavior fuel models were derived from these fuelbeds. LANDFIRE developed surface fire behavior fuel models and canopy attributes for the U.S. using satellite imagery informed by field data. The Southern Wildfire Risk Assessment (SWRA) developed surface fire behavior fuel models and canopy cover for the southeastern U.S. using satellite imagery.

  5. Experimental study and modeling of degradation phenomena in HTPEM fuel cell stacks for use in CHP systems

    E-Print Network [OSTI]

    Berning, Torsten

    Experimental study and modeling of degradation phenomena in HTPEM fuel cell stacks for use in CHP://www.iet.aau.dk ­ * Corresponding author: mpn@iet.aau.dk Abstract: Degradation phenomena in HTPEM fuel cells for use in CHP systems monitored during experiments. Introduction Fuel cell based combined heat and power production (CHP) systems

  6. ESTIMATION OF ETHANOL CONTENT IN FLEX-FUEL VEHICLES USING AN EXHAUST GAS OXYGEN SENSOR: MODEL, TUNING AND SENSITIVITY

    E-Print Network [OSTI]

    Stefanopoulou, Anna

    ESTIMATION OF ETHANOL CONTENT IN FLEX-FUEL VEHICLES USING AN EXHAUST GAS OXYGEN SENSOR: MODEL periods of intense interest in using ethanol as an alternative fuel to petroleum-based gasoline and diesel derivatives. Currently available flexible fuel vehicles (FFVs) can operate on a blend of gasoline and ethanol

  7. Combustion Phasing Model for Control of a Gasoline-Ethanol Fueled SI Engine with Variable Valve Timing

    E-Print Network [OSTI]

    Combustion Phasing Model for Control of a Gasoline-Ethanol Fueled SI Engine with Variable Valve engine efficiency. Fuel-flexible engines permit the increased use of ethanol-gasoline blends. Ethanol points across the engine operating range for four blends of gasoline and ethanol. I. INTRODUCTION Fuel

  8. Mathematical Modeling of Liquid-Feed Direct Methanol Fuel Z. H. Wang* and C. Y. Wang*,z

    E-Print Network [OSTI]

    Mathematical Modeling of Liquid-Feed Direct Methanol Fuel Cells Z. H. Wang* and C. Y. Wang for liquid-feed direct methanol fuel cells DMFC . In addition to the anode and cathode electrochemical electronically March 4, 2003. Fuel cells promise to replace the internal combustion engine in transportation due

  9. A Mathematical Model for Predicting the Life of PEM Fuel Cell Membranes Subjected to Hydration Cycling

    E-Print Network [OSTI]

    S. F. Burlatsky; M. Gummalla; J. O'Neill; V. V. Atrazhev; A. N. Varyukhin; D. V. Dmitriev; N. S. Erikhman

    2013-06-19T23:59:59.000Z

    Under typical PEM fuel cell operating conditions, part of membrane electrode assembly is subjected to humidity cycling due to variation of inlet gas RH and/or flow rate. Cyclic membrane hydration/dehydration would cause cyclic swelling/shrinking of the unconstrained membrane. In a constrained membrane, it causes cyclic stress resulting in mechanical failure in the area adjacent to the gas inlet. A mathematical modeling framework for prediction of the lifetime of a PEM FC membrane subjected to hydration cycling is developed in this paper. The model predicts membrane lifetime as a function of RH cycling amplitude and membrane mechanical properties. The modeling framework consists of three model components: a fuel cell RH distribution model, a hydration/dehydration induced stress model that predicts stress distribution in the membrane, and a damage accrual model that predicts membrane life-time. Short descriptions of the model components along with overall framework are presented in the paper. The model was used for lifetime prediction of a GORE-SELECT membrane.

  10. Core-crust transition properties of neutron stars within systematically varied extended relativistic mean-field model

    E-Print Network [OSTI]

    A. Sulaksono; Naosad Alam; B. K. Agrawal

    2014-11-03T23:59:59.000Z

    The model dependence and the symmetry energy dependence of the core-crust transition properties for the neutron stars are studied using three different families of systematically varied extended relativistic mean field model. Several forces within each of the families are so considered that they yield wide variations in the values of the nuclear symmetry energy $a_{\\rm sym}$ and its slope parameter $L$ at the saturation density. The core-crust transition density is calculated using a method based on random-phase-approximation. The core-crust transition density is strongly correlated, in a model independent manner, with the symmetry energy slope parameter evaluated at the saturation density. The pressure at the transition point dose not show any meaningful correlations with the symmetry energy parameters at the saturation density. At best, pressure at the transition point is correlated with the symmetry energy parameters and their linear combination evaluated at the some sub-saturation density. Yet, such correlations might not be model independent. The correlations of core-crust transition properties with the symmetry energy parameter are also studied by varying the symmetry energy within a single model. The pressure at the transition point is correlated once again with the symmetry energy parameter at the sub-saturation density.

  11. Introduction to Focus Issue: Rhythms and Dynamic Transitions in Neurological Disease: Modeling, Computation, and Experiment

    SciTech Connect (OSTI)

    Kaper, Tasso J., E-mail: tasso@bu.edu; Kramer, Mark A., E-mail: mak@bu.edu [Department of Mathematics and Statistics, Boston University, Boston, Massachusetts 02215 (United States); Rotstein, Horacio G., E-mail: horacio@njit.edu [Department of Mathematical Sciences, New Jersey Institute of Technology, Newark, New Jersey 07102 (United States)

    2013-12-15T23:59:59.000Z

    Rhythmic neuronal oscillations across a broad range of frequencies, as well as spatiotemporal phenomena, such as waves and bumps, have been observed in various areas of the brain and proposed as critical to brain function. While there is a long and distinguished history of studying rhythms in nerve cells and neuronal networks in healthy organisms, the association and analysis of rhythms to diseases are more recent developments. Indeed, it is now thought that certain aspects of diseases of the nervous system, such as epilepsy, schizophrenia, Parkinson's, and sleep disorders, are associated with transitions or disruptions of neurological rhythms. This focus issue brings together articles presenting modeling, computational, analytical, and experimental perspectives about rhythms and dynamic transitions between them that are associated to various diseases.

  12. Hydrogen Transition Infrastructure Analysis

    SciTech Connect (OSTI)

    Melendez, M.; Milbrandt, A.

    2005-05-01T23:59:59.000Z

    Presentation for the 2005 U.S. Department of Energy Hydrogen Program review analyzes the hydrogen infrastructure needed to accommodate a transitional hydrogen fuel cell vehicle demand.

  13. Using System Dynamics to Model the Transition to Biofuels in the United States

    SciTech Connect (OSTI)

    Bush, B.; Duffy, M.; Sandor, D.; Peterson, S.

    2008-01-01T23:59:59.000Z

    Today, the U.S. consumes almost 21 million barrels of crude oil per day; approximately 60% of the U.S. demand is supplied by imports. The transportation sector alone accounts for two-thirds of U.S. petroleum use. Biofuels, liquid fuels produced from domestically-grown biomass, have the potential to displace about 30% of current U.S. gasoline consumption. Transitioning to a biofuels industry on this scale will require the creation of a robust biomass-to-biofuels system-of-systems that operates in concert with the existing agriculture, forestry, energy, and transportation markets. The U.S. Department of Energy is employing a system dynamics approach to investigate potential market penetration scenarios for cellulosic ethanol, and to aid decision makers in focusing government actions on the areas with greatest potential to accelerate the deployment of biofuels and ultimately reduce the nationpsilas dependence on imported oil.

  14. Environmental Aspects of Advanced Nuclear Fuel Cycles: Parametric Modeling and Preliminary Analysis 

    E-Print Network [OSTI]

    Yancey, Kristina D.

    2010-07-14T23:59:59.000Z

    and reprocessing spent fuel must be incorporated into the nuclear fuel cycle to achieve sustainability....

  15. FATE Unified Modeling Method for Spent Nuclear Fuel and Sludge Processing, Shipping and Storage - 13405

    SciTech Connect (OSTI)

    Plys, Martin; Burelbach, James; Lee, Sung Jin; Apthorpe, Robert [Fauske and Associates, LLC, 16W070 83rd St., Burr Ridge, IL, 60527 (United States)] [Fauske and Associates, LLC, 16W070 83rd St., Burr Ridge, IL, 60527 (United States)

    2013-07-01T23:59:59.000Z

    A unified modeling method applicable to the processing, shipping, and storage of spent nuclear fuel and sludge has been incrementally developed, validated, and applied over a period of about 15 years at the US DOE Hanford site. The software, FATE{sup TM}, provides a consistent framework for a wide dynamic range of common DOE and commercial fuel and waste applications. It has been used during the design phase, for safety and licensing calculations, and offers a graded approach to complex modeling problems encountered at DOE facilities and abroad (e.g., Sellafield). FATE has also been used for commercial power plant evaluations including reactor building fire modeling for fire PRA, evaluation of hydrogen release, transport, and flammability for post-Fukushima vulnerability assessment, and drying of commercial oxide fuel. FATE comprises an integrated set of models for fluid flow, aerosol and contamination release, transport, and deposition, thermal response including chemical reactions, and evaluation of fire and explosion hazards. It is one of few software tools that combine both source term and thermal-hydraulic capability. Practical examples are described below, with consideration of appropriate model complexity and validation. (authors)

  16. Models for the Configuration and Integrity of Partially Oxidized Fuel Rod Cladding at High Temperatures

    SciTech Connect (OSTI)

    Siefken, L.J.

    1999-01-01T23:59:59.000Z

    Models were designed to resolve deficiencies in the SCDAP/RELAP5/MOD3.2 calculations of the configuration and integrity of hot, partially oxidized cladding. These models are expected to improve the calculations of several important aspects of fuel rod behavior. First, an improved mapping was established from a compilation of PIE results from severe fuel damage tests of the configuration of melted metallic cladding that is retained by an oxide layer. The improved mapping accounts for the relocation of melted cladding in the circumferential direction. Then, rules based on PIE results were established for calculating the effect of cladding that has relocated from above on the oxidation and integrity of the lower intact cladding upon which it solidifies. Next, three different methods were identified for calculating the extent of dissolution of the oxidic part of the cladding due to its contact with the metallic part. The extent of dissolution effects the stress and thus the integrity of the oxidic part of the cladding. Then, an empirical equation was presented for calculating the stress in the oxidic part of the cladding and evaluating its integrity based on this calculated stress. This empirical equation replaces the current criterion for loss of integrity which is based on temperature and extent of oxidation. Finally, a new rule based on theoretical and experimental results was established for identifying the regions of a fuel rod with oxidation of both the inside and outside surfaces of the cladding. The implementation of these models is expected to eliminate the tendency of the SCDAP/RELAP5 code to overpredict the extent of oxidation of the upper part of fuel rods and to underpredict the extent of oxidation of the lower part of fuel rods and the part with a high concentration of relocated material. This report is a revision and reissue of the report entitled, Improvements in Modeling of Cladding Oxidation and Meltdown.

  17. Exploratory fuel-cell research: I. Direct-hydrocarbon polymer-electrolyte fuel cell. II. Mathematical modeling of fuel-cell cathodes

    SciTech Connect (OSTI)

    Perry, M.L.; McLarnon, F.R.; Newman, J.S.; Cairns, E.J.

    1996-12-01T23:59:59.000Z

    A strong need exists today for more efficient energy-conversion systems. Our reliance on limited fuel resources, such as petroleum for the majority of our energy needs makes it imperative that we utilize these resources as efficiently as possible. Higher-efficiency energy conversion also means less pollution, since less fuel is consumed and less exhaust created for the same energy output. Additionally, for many industrialized nations, such as the United States which must rely on petroleum imports, it is also imperative from a national-security standpoint to reduce the consumption of these precious resources. A substantial reduction of U.S. oil imports would result in a significant reduction of our trade deficit, as well as costly military spending to protect overseas petroleum resources. Therefore, energy-conversion devices which may utilize alternative fuels are also in strong demand. This paper describes research on fuel cells for transportation.

  18. WaterTransport in PEM Fuel Cells: Advanced Modeling, Material Selection, Testing and Design Optimization

    SciTech Connect (OSTI)

    J. Vernon Cole; Abhra Roy; Ashok Damle; Hari Dahr; Sanjiv Kumar; Kunal Jain; Ned Djilai

    2012-10-02T23:59:59.000Z

    Water management in Proton Exchange Membrane, PEM, Fuel Cells is challenging because of the inherent conflicts between the requirements for efficient low and high power operation. Particularly at low powers, adequate water must be supplied to sufficiently humidify the membrane or protons will not move through it adequately and resistance losses will decrease the cell efficiency. At high power density operation, more water is produced at the cathode than is necessary for membrane hydration. This excess water must be removed effectively or it will accumulate in the Gas Diffusion Layers, GDLs, between the gas channels and catalysts, blocking diffusion paths for reactants to reach the catalysts and potentially flooding the electrode. As power density of the cells is increased, the challenges arising from water management are expected to become more difficult to overcome simply due to the increased rate of liquid water generation relative to fuel cell volume. Thus, effectively addressing water management based issues is a key challenge in successful application of PEMFC systems. In this project, CFDRC and our partners used a combination of experimental characterization, controlled experimental studies of important processes governing how water moves through the fuel cell materials, and detailed models and simulations to improve understanding of water management in operating hydrogen PEM fuel cells. The characterization studies provided key data that is used as inputs to all state-of-the-art models for commercially important GDL materials. Experimental studies and microscopic scale models of how water moves through the GDLs showed that the water follows preferential paths, not branching like a river, as it moves toward the surface of the material. Experimental studies and detailed models of water and airflow in fuel cells channels demonstrated that such models can be used as an effective design tool to reduce operating pressure drop in the channels and the associated costs and weight of blowers and pumps to force air and hydrogen gas through the fuel cell. Promising improvements to materials structure and surface treatments that can potentially aid in managing the distribution and removal of liquid water were developed; and improved steady-state and freeze-thaw performance was demonstrated for a fuel cell stack under the self-humidified operating conditions that are promising for stationary power generation with reduced operating costs.

  19. Modelling the chromosphere and transition region of Epsilon Eri (K2 V)

    E-Print Network [OSTI]

    S. A. Sim; C. Jordan

    2005-06-02T23:59:59.000Z

    Measurements of ultraviolet line fluxes from Space Telescope Imaging Spectrograph and Far-Ultraviolet Spectroscopic Explorer spectra of the K2-dwarf Epsilon Eri are reported. These are used to develop new emission measure distributions and semi-empirical atmospheric models for the chromosphere and lower transition region of the star. These models are the most detailed constructed to date for a main-sequence star other than the Sun. New ionisation balance calculations, which account for the effect of finite density on dielectronic recombination rates, are presented for carbon, nitrogen, oxygen and silicon. The results of these calculations are significantly different from the standard Arnaud & Rothenflug ion balance, particularly for alkali-like ions. The new atmospheric models are used to place constraints on possible First Ionisation Potential (FIP) related abundance variations in the lower atmosphere and to discuss limitations of single-component models for the interpretation of certain optically thick line fluxes.

  20. Development of Novel PEM Membrane and Multiphase CD Modeling of PEM Fuel Cell

    SciTech Connect (OSTI)

    K. J. Berry; Susanta Das

    2009-12-30T23:59:59.000Z

    To understand heat and water management phenomena better within an operational proton exchange membrane fuel cell's (PEMFC) conditions, a three-dimensional, two-phase computational fluid dynamic (CFD) flow model has been developed and simulated for a complete PEMFC. Both liquid and gas phases are considered in the model by taking into account the gas flow, diffusion, charge transfer, change of phase, electro-osmosis, and electrochemical reactions to understand the overall dynamic behaviors of species within an operating PEMFC. The CFD model is solved numerically under different parametric conditions in terms of water management issues in order to improve cell performance. The results obtained from the CFD two-phase flow model simulations show improvement in cell performance as well as water management under PEMFCs operational conditions as compared to the results of a single phase flow model available in the literature. The quantitative information obtained from the two-phase model simulation results helped to develop a CFD control algorithm for low temperature PEM fuel cell stacks which opens up a route in designing improvement of PEMFC for better operational efficiency and performance. To understand heat and water management phenomena better within an operational proton exchange membrane fuel cell's (PEMFC) conditions, a three-dimensional, two-phase computational fluid dynamic (CFD) flow model has been developed and simulated for a complete PEMFC. Both liquid and gas phases are considered in the model by taking into account the gas flow, diffusion, charge transfer, change of phase, electro-osmosis, and electrochemical reactions to understand the overall dynamic behaviors of species within an operating PEMFC. The CFD model is solved numerically under different parametric conditions in terms of water management issues in order to improve cell performance. The results obtained from the CFD two-phase flow model simulations show improvement in cell performance as well as water management under PEMFCs operational conditions as compared to the results of a single phase flow model available in the literature. The quantitative information obtained from the two-phase model simulation results helped to develop a CFD control algorithm for low temperature PEM fuel cell stacks which opens up a route in designing improvement of PEMFC for better operational efficiency and performance.

  1. Exploration of Novel Fuels for Gas Turbine (ENV-406) Modeling of T60 Test Rig with Diesel & Biodiesel Fuels

    E-Print Network [OSTI]

    & Biodiesel Fuels Mémoire Mina Youssef Maîtrise en génie mécanique Maître ès sciences (M.Sc.) Québec, Canada de biodiesel B20. La matrice de test numérique constitue de quatre cas d'écoulement réactifs c to simulate the liquid combustion of conventional and non- conventional biodiesel fuels, in particularly the B

  2. Refinery fuel oxygenates in view of the complex model for reformulated gasline

    SciTech Connect (OSTI)

    Crawford, C.D.; Haelsig, C.P. [Fluor Daniel, Irvine, CA (United States)

    1994-12-31T23:59:59.000Z

    The final version of the Complex Model for reformulated gasoline (RFG) has now been issued with some surprising features that will significantly affect refinery fuel oxygenates planning. These include the following: (1) The only oxygenates included in the model are MTBE, ETBE, TAME, and Ethanol. (2) The Complex Model calculates that MTBE and TAME are significantly more effective for reduction of air toxics emissions than Ethanol and ETBE. (3) The Complex Model calculates that MTBE and TAME typically produce about equal reduction in air toxics emissions at the same RFG oxygen content. Although gasoline certification by the Complex Model is optional prior to 1998, after 1998 it will be mandatory for both reformulated and conventional gasolines. This paper considers refinery oxygenates production in view of these features of the Complex Model for RFG, basing the discussion on 2.0 weight percent oxygen content for RFG.

  3. Alternative Fuels Data Center

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

    Alternative Fuel Vehicle (AFV) Acquisition Requirements State agencies must purchase flexible fuel vehicles (FFVs) capable of operating on E85 fuel unless the desired vehicle model...

  4. Coupling the Mixed Potential and Radiolysis Models for Used Fuel Degradation

    SciTech Connect (OSTI)

    Buck, Edgar C.; Jerden, James L.; Ebert, William L.; Wittman, Richard S.

    2013-08-30T23:59:59.000Z

    The primary purpose of this report is to describe the strategy for coupling three process level models to produce an integrated Used Fuel Degradation Model (FDM). The FDM, which is based on fundamental chemical and physical principals, provides direct calculation of radionuclide source terms for use in repository performance assessments. The G-value for H2O2 production (Gcond) to be used in the Mixed Potential Model (MPM) (H2O2 is the only radiolytic product presently included but others will be added as appropriate) needs to account for intermediate spur reactions. The effects of these intermediate reactions on [H2O2] are accounted for in the Radiolysis Model (RM). This report details methods for applying RM calculations that encompass the effects of these fast interactions on [H2O2] as the solution composition evolves during successive MPM iterations and then represent the steady-state [H2O2] in terms of an “effective instantaneous or conditional” generation value (Gcond). It is anticipated that the value of Gcond will change slowly as the reaction progresses through several iterations of the MPM as changes in the nature of fuel surface occur. The Gcond values will be calculated with the RM either after several iterations or when concentrations of key reactants reach threshold values determined from previous sensitivity runs. Sensitivity runs with RM indicate significant changes in G-value can occur over narrow composition ranges. The objective of the mixed potential model (MPM) is to calculate the used fuel degradation rates for a wide range of disposal environments to provide the source term radionuclide release rates for generic repository concepts. The fuel degradation rate is calculated for chemical and oxidative dissolution mechanisms using mixed potential theory to account for all relevant redox reactions at the fuel surface, including those involving oxidants produced by solution radiolysis and provided by the radiolysis model (RM). The RM calculates the concentration of species generated at any specific time and location from the surface of the fuel. Several options being considered for coupling the RM and MPM are described in the report. Different options have advantages and disadvantages based on the extent of coding that would be required and the ease of use of the final product.

  5. Asynchronous-Transition HMM 

    E-Print Network [OSTI]

    Matsuda, Shigeki; Nakai, Mitsuru; Shimodaira, Hiroshi; Sagayama, Shigeki

    We propose a new class of hidden Markov model (HMM) called asynchronous-transition HMM (AT-HMM). Opposed to conventional HMMs where hidden state transition occurs simultaneously to all features, the new class of HMM allows state transitions...

  6. Preliminary Design Report for Modeling of Hydrogen Uptake in Fuel Rod Cladding During Severe Accidents

    SciTech Connect (OSTI)

    Siefken, Larry James

    1999-02-01T23:59:59.000Z

    Preliminary designs are described for models of hydrogen and oxygen uptake in fuel rod cladding during severe accidents. Calculation of the uptake involves the modeling of seven processes: (1) diffusion of oxygen from the bulk gas into the boundary layer at the external cladding surface, (2) diffusion from the boundary layer into the oxide layer, (3) diffusion from the inner surface of the oxide layer into the metallic part of the cladding, (4) uptake of hydrogen in the event that the clad-ding oxide layer is dissolved in a steam-starved region, (5) embrittlement of cladding due to hydrogen uptake, (6) cracking of cladding during quenching due to its embrittlement and (7) release of hydrogen from the cladding after cracking of the cladding. An integral diffusion method is described for calculating the diffusion processes in the cladding. Experimental results are presented that show a rapid uptake of hydrogen in the event of dissolution of the oxide layer and a rapid release of hydrogen in the event of cracking of the oxide layer. These experimental results are used as a basis for calculating the rate of hydrogen uptake and the rate of hydrogen release. The uptake of hydrogen is limited to the equilibrium solubility calculated by applying Sievert's law. The uptake of hydrogen is an exothermic reaction that accelerates the heatup of a fuel rod. An embrittlement criteria is described that accounts for hydrogen and oxygen concentration and the extent of oxidation. A design is described for implementing the models for hydrogen and oxygen uptake and cladding embrittlement into the programming framework of the SCDAP/RELAP5 code. A test matrix is described for assessing the impact of the proposed models on the calculated behavior of fuel rods in severe accident conditions. This report is a revision and reissue of the report entitled; "Preliminary Design Report for Modeling of Hydrogen Uptake in Fuel Rod Cladding During Severe Accidents."

  7. Uranium Nitride as LWR TRISO Fuel: Thermodynamic Modeling of U-C-N

    SciTech Connect (OSTI)

    Besmann, Theodore M [ORNL; Shin, Dongwon [ORNL

    2012-01-01T23:59:59.000Z

    TRISO coated particle fuel is envisioned as a next generation replacement for current urania pellet fuel in LWR applications. To obtain adequate fissile loading the kernel of the TRISO particle will need to be UN. In support of the fuel development effort, an assessment of phase regions of interest in the U-C-N system was undertaken as the fuel will be prepared by the carbothermic reduction of the oxide and it will be in equilibrium with carbon within the TRISO particle. The phase equilibria and thermochemistry of the U-C-N system is reviewed, including nitrogen pressure measurements above various phase fields. Selected measurements were used to fit a first order model of the UC1-xNx phase, represented by the inter-solution of UN and UC. Fit to the data was significantly improved by also adjusting the heat of formation for UN by ~12 kJ/mol and the phase equilbria was best reproduced by also adjusting the heat for U2N3 by +XXX. The determined interaction parameters yielded a slightly positive deviation from ideality, which agrees with lattice parameter measurements which show positive deviation from Vegard s law. The resultant model together with reported values for other phases in the system were used to generate isothermal sections of the U-C-N phase diagram. Nitrogen partial pressures were also computed for regions of interest.

  8. A Multiphase Model for Cold Start of Polymer Electrolyte Fuel Leng Mao, Chao-Yang Wang,*,z

    E-Print Network [OSTI]

    A Multiphase Model for Cold Start of Polymer Electrolyte Fuel Cells Leng Mao, Chao-Yang Wang, The Pennsylvania State University, University Park, Pennsylvania 16802, USA A multiphase and transient model

  9. Modelling of thermo-mechanical and irradiation behavior of metallic and oxide fuels for sodium fast reactors

    E-Print Network [OSTI]

    Karahan, Aydin

    2009-01-01T23:59:59.000Z

    A robust and reliable code to model the irradiation behavior of metal and oxide fuels in sodium cooled fast reactors is developed. Modeling capability was enhanced by adopting a non-empirical mechanistic approach to the ...

  10. Journal of Power Sources 164 (2007) 189195 Modeling water transport in liquid feed direct methanol fuel cells

    E-Print Network [OSTI]

    2007-01-01T23:59:59.000Z

    Journal of Power Sources 164 (2007) 189­195 Modeling water transport in liquid feed direct methanol management in direct methanol fuel cells (DMFCs) is very critical and complicated because of many interacting rights reserved. Keywords: Direct methanol fuel cell; Water transport; Mathematical modeling; Three

  11. An Integrated Electric Power Supply Chain and Fuel Market Network Framework: Theoretical Modeling with Empirical Analysis for New England

    E-Print Network [OSTI]

    Nagurney, Anna

    a critical infrastructure for the functioning of our modern economies and societies. Electric power lightsAn Integrated Electric Power Supply Chain and Fuel Market Network Framework: Theoretical Modeling Abstract: In this paper, we develop a novel electric power supply chain network model with fuel supply

  12. Physical and chemical comparison of soot in hydrocarbon and biodiesel fuel diffusion flames: A study of model and commercial fuels

    SciTech Connect (OSTI)

    Matti Maricq, M. [Research and Advanced Engineering, Ford Motor Company, Dearborn, MI (United States)

    2011-01-15T23:59:59.000Z

    Data are presented to compare soot formation in both surrogate and practical fatty acid methyl ester biodiesel and petroleum fuel diffusion flames. The approach here uses differential mobility analysis to follow the size distributions and electrical charge of soot particles as they evolve in the flame, and laser ablation particle mass spectrometry to elucidate their composition. Qualitatively, these soot properties exhibit a remarkably similar development along the flames. The size distributions begin as a single mode of precursor nanoparticles, evolve through a bimodal phase marking the onset of aggregate formation, and end in a self preserving mode of fractal-like particles. Both biodiesel and hydrocarbon fuels yield a common soot composition dominated by C{sub x}H{sub y}{sup +} ions, stabilomer PAHs, and fullerenes in the positive ion mass spectrum, and C{sub x}{sup -} and C{sub 2x}H{sup -} in the negative ion spectrum. These ion intensities initially grow with height in the diffusion flames, but then decline during later stages, consistent with soot carbonization. There are important quantitative differences between fuels. The surrogate biodiesel fuel methyl butanoate substantially reduces soot levels, but soot formation and evolution in this flame are delayed relative to both soy and petroleum fuels. In contrast, soots from soy and hexadecane flames exhibit nearly quantitative agreement in their size distribution and composition profiles with height, suggesting similar soot precursor chemistry. (author)

  13. Dark matter and strong electroweak phase transition in a radiative neutrino mass model

    SciTech Connect (OSTI)

    Ahriche, Amine [Department of Physics, University of Jijel, PB 98 Ouled Aissa, DZ-18000 Jijel (Algeria); Nasri, Salah, E-mail: aahriche@ictp.it, E-mail: snasri@uaeu.ac.ae [Physics Department, UAE University, POB 17551, Al Ain (United Arab Emirates)

    2013-07-01T23:59:59.000Z

    We consider an extension of the standard model (SM) with charged singlet scalars and right handed (RH) neutrinos all at the electroweak scale. In this model, the neutrino masses are generated at three loops, which provide an explanation for their smallness, and the lightest RH neutrino, N{sub 1}, is a dark matter candidate. We find that for three generations of RH neutrinos, the model can be consistent with the neutrino oscillation data, lepton flavor violating processes, N{sub 1} can have a relic density in agreement with the recent Planck data, and the electroweak phase transition can be strongly first order. We also show that the charged scalars may enhance the branching ratio h???, where as h??Z get can get few percent suppression. We also discuss the phenomenological implications of the RH neutrinos at the collider.

  14. Non-equilibrium phase transition in an exactly solvable driven Ising model with friction

    E-Print Network [OSTI]

    Alfred Hucht

    2009-11-04T23:59:59.000Z

    A driven Ising model with friction due to magnetic correlations has recently been proposed by Kadau et al. (Phys. Rev. Lett. 101, 137205 (2008)). The non-equilibrium phase transition present in this system is investigated in detail using analytical methods as well as Monte Carlo simulations. In the limit of high driving velocities $v$ the model shows mean field behavior due to dimensional reduction and can be solved exactly for various geometries. The simulations are performed with three different single spin flip rates: the common Metropolis and Glauber rates as well as a multiplicative rate. Due to the non-equilibrium nature of the model all rates lead to different critical temperatures at $v>0$, while the exact solution matches the multiplicative rate. Finally, the cross-over from Ising to mean field behavior as function of velocity and system size is analysed in one and two dimensions.

  15. A Unified Cohesive Zone Approach to Model Ductile Brittle Transition in Reactor Pressure Vessel Steels

    SciTech Connect (OSTI)

    Pritam Chakraborty; S. Bulent Biner

    2014-08-01T23:59:59.000Z

    In this study, a unified cohesive zone model has been proposed to predict, Ductile to Brittle Transition, DBT, in Reactor Pressure Vessel, RPV, steels. A general procedure is described to obtain the Cohesive Zone Model, CZM, parameters for the different temperatures and fracture probabilities. In order to establish the full master-curve, the procedure requires three calibration points with one at the upper-shelf for ductile fracture and two for the fracture probabilities, Pf, of 5% and 95% at the lower-shelf. In the current study, these calibrations were carried out by utilizing the experimental fracture toughness values and flow curves. After the calibration procedure, the simulations of fracture behavior (ranging from completely unstable to stable crack extension behavior) in one inch thick compact tension specimens at different temperatures yielded values that were comparable to the experimental fracture toughness values, indicating the viability of such unified modeling approach.

  16. Block entropy and quantum phase transition in the anisotropic Kondo necklace model

    SciTech Connect (OSTI)

    Mendoza-Arenas, J. J.; Franco, R.; Silva-Valencia, J. [Departamento de Fisica, Universidad Nacional de Colombia, Bogota (Colombia)

    2010-06-15T23:59:59.000Z

    We study the von Neumann block entropy in the Kondo necklace model for different anisotropies {eta} in the XY interaction between conduction spins using the density matrix renormalization group method. It was found that the block entropy presents a maximum for each {eta} considered, and, comparing it with the results of the quantum criticality of the model based on the behavior of the energy gap, we observe that the maximum block entropy occurs at the quantum critical point between an antiferromagnetic and a Kondo singlet state, so this measure of entanglement is useful for giving information about where a quantum phase transition occurs in this model. We observe that the block entropy also presents a maximum at the quantum critical points that are obtained when an anisotropy {Delta} is included in the Kondo exchange between localized and conduction spins; when {Delta} diminishes for a fixed value of {eta}, the critical point increases, favoring the antiferromagnetic phase.

  17. Detailed OEDGE modeling of core-pedestal fueling in DIII-D

    SciTech Connect (OSTI)

    Elder, J. D. [University of Toronto, Canada; Leonard, A. W. [General Atomics; Stangeby, P. C. [University of Toronto, Canada; Boedo, J.A. [University of California, San Diego; Bray, B. D. [General Atomics, San Diego; Brooks, N. H. [General Atomics, San Diego; Fenstermacher, M. E. [Lawrence Livermore National Laboratory (LLNL); Reiter, D. [Forschungszentrum Julich, Julich, Germany; Unterberg, Ezekial A [ORNL; Watkins, J. G. [Sandia National Laboratories (SNL); Lisgo, S. [EURATOM CCFE Fus Assoc, Culham Sci Ctr, Abingdon, Oxon, England

    2013-01-01T23:59:59.000Z

    The OEDGE code is used to model core fueling for attached L-mode plasmas and between edge localized modes (ELMs) for attached H-mode plasmas in DIII-D. Empirical plasma reconstruction has been used to determine the plasma conditions in these discharges. EIRENE is used to model the hydrogen recycling. Divertor recycling accounts for 65 100% of the core fueling. The fraction of the total divertor target flux ionized inside the separatrix ranges from 5% to 20%. The fraction of total wall flux ionized inside the separatrix ranges from 20% to 50%. Neutrals originating from wall regions closer to the separatrix are more likely to ionize in the confined plasma. Ionization in the confined plasma is concentrated below the midplane with peaks in the poloidal profiles just above the X-point. Radial core ionization in high density H-mode is peaked strongly near the separatrix.

  18. Modeling of fission product release from HTR (high temperature reactor) fuel for risk analyses

    SciTech Connect (OSTI)

    Bolin, J.; Verfondern, K.; Dunn, T.; Kania, M.

    1989-07-01T23:59:59.000Z

    The US and FRG have developed methodologies to determine the performance of and fission product release from TRISO-coated fuel particles under postulated accident conditions. The paper presents a qualitative and quantitative comparison of US and FRG models. The models are those used by General Atomics (GA) and by the German Nuclear Research Center at Juelich (KFA/ISF). A benchmark calculation was performed for fuel temperatures predicted for the US Department of Energy sponsored Modular High Temperature Gas Cooled Reactor (MHTGR). Good agreement in the benchmark calculations supports the on-going efforts to verify and validate the independently developed codes of GA and KFA/ISF. This work was performed under the US/FRG Umbrella Agreement for Cooperation on Gas Cooled Reactor Development. 6 refs., 3 figs., 3 tabs.

  19. A holographic model for antiferromagnetic quantum phase transition induced by magnetic field

    E-Print Network [OSTI]

    Rong-Gen Cai; Run-Qiu Yang; F. V. Kusmartsev

    2015-01-19T23:59:59.000Z

    We propose a gravity dual of antiferromagnetic quantum phase transition (QPT) induced by magnetic field and study the criticality in the vicinity of quantum critical point (QCP). Results show the boundary critical theory is a strong coupling theory with dynamic exponent $z=2$. The hyperscaling law is violated and logarithmic corrections appear near the QCP. We compare our theoretical results with experimental data on variety of materials including low-dimensional magnet, BiCoPO$_5$ and pyrochlores, Er$_{2-2x}$Y$_{2x}$Ti$_2$O$_7$. Our model describes well the existing experiments and predicts QCP and other high field magnetic properties of these compounds.

  20. A holographic model for antiferromagnetic quantum phase transition induced by magnetic field

    E-Print Network [OSTI]

    Cai, Rong-Gen; Kusmartsev, F V

    2015-01-01T23:59:59.000Z

    We propose a gravity dual of antiferromagnetic quantum phase transition (QPT) induced by magnetic field and study the criticality in the vicinity of quantum critical point (QCP). Results show the boundary critical theory is a strong coupling theory with dynamic exponent $z=2$. The hyperscaling law is violated and logarithmic corrections appear near the QCP. We compare our theoretical results with experimental data on variety of materials including low-dimensional magnet, BiCoPO$_5$ and pyrochlores, Er$_{2-2x}$Y$_{2x}$Ti$_2$O$_7$. Our model describes well the existing experiments and predicts QCP and other high field magnetic properties of these compounds.

  1. An evaluation of thermal modeling techniques utilized for nuclear fuel rods

    E-Print Network [OSTI]

    Simmons, Jeffrey Warren

    1989-01-01T23:59:59.000Z

    modeling techniques. Lassmann [23] states that comparisons of code predictions and experimental results or comparisons between different codes often show rather large differences. A code review conducted by EPRI (Electric Power Research Institute) [24... performance codes. Two earlier reviews on fuel performance codes were conducted by EPRI in 1979 and Kummerer in 1976 [26]. The EPRI review compares the codes capabilities as well as their predictions to selected experimental results. The Kummerer review...

  2. Modeling and Optimization of PEMFC Systems and its Application to Direct Hydrogen Fuel Cell Vehicles

    E-Print Network [OSTI]

    Zhao, Hengbing; Burke, Andy

    2008-01-01T23:59:59.000Z

    operating conditions. Direct Hydrogen Fuel Cell System Modelconditions for a direct hydrogen fuel cell system Table 1simulation tool for hydrogen fuel cell vehicles, Journal of

  3. Using a Quasipotential Transformation for Modeling Diffusion Media in Polymer-Electrolyte Fuel Cells

    E-Print Network [OSTI]

    Weber, Adam Z.

    2008-01-01T23:59:59.000Z

    Proton Exchange Membrane Fuel Cell , Numerical Heat Transferof Polymer Electrolyte Fuel Cells Using a Two-EquationExchange Membrane Fuel Cells 2. Absolute Permeability ,

  4. TRISO Fuel Performance: Modeling, Integration into Mainstream Design Studies, and Application to a Thorium-fueled Fusion-Fission Hybrid Blanket

    SciTech Connect (OSTI)

    Powers, J J

    2011-11-28T23:59:59.000Z

    This study focused on creating a new tristructural isotropic (TRISO) coated particle fuel performance model and demonstrating the integration of this model into an existing system of neutronics and heat transfer codes, creating a user-friendly option for including fuel performance analysis within system design optimization and system-level trade-off studies. The end product enables both a deeper understanding and better overall system performance of nuclear energy systems limited or greatly impacted by TRISO fuel performance. A thorium-fueled hybrid fusion-fission Laser Inertial Fusion Energy (LIFE) blanket design was used for illustrating the application of this new capability and demonstrated both the importance of integrating fuel performance calculations into mainstream design studies and the impact that this new integrated analysis had on system-level design decisions. A new TRISO fuel performance model named TRIUNE was developed and verified and validated during this work with a novel methodology established for simulating the actual lifetime of a TRISO particle during repeated passes through a pebble bed. In addition, integrated self-consistent calculations were performed for neutronics depletion analysis, heat transfer calculations, and then fuel performance modeling for a full parametric study that encompassed over 80 different design options that went through all three phases of analysis. Lastly, side studies were performed that included a comparison of thorium and depleted uranium (DU) LIFE blankets as well as some uncertainty quantification work to help guide future experimental work by assessing what material properties in TRISO fuel performance modeling are most in need of improvement. A recommended thorium-fueled hybrid LIFE engine design was identified with an initial fuel load of 20MT of thorium, 15% TRISO packing within the graphite fuel pebbles, and a 20cm neutron multiplier layer with beryllium pebbles in flibe molten salt coolant. It operated at a system power level of 2000 MW{sub th}, took about 3.5 years to reach full plateau power, and was capable of an End of Plateau burnup of 38.7 %FIMA if considering just the neutronic constraints in the system design; however, fuel performance constraints led to a maximum credible burnup of 12.1 %FIMA due to a combination of internal gas pressure and irradiation effects on the TRISO materials (especially PyC) leading to SiC pressure vessel failures. The optimal neutron spectrum for the thorium-fueled blanket options evaluated seemed to favor a hard spectrum (low but non-zero neutron multiplier thicknesses and high TRISO packing fractions) in terms of neutronic performance but the fuel performance constraints demonstrated that a significantly softer spectrum would be needed to decrease the rate of accumulation of fast neutron fluence in order to improve the maximum credible burnup the system could achieve.

  5. A Lifecycle Emissions Model (LEM): Lifecycle Emissions from Transportation Fuels, Motor Vehicles, Transportation Modes, Electricity Use, Heating and Cooking Fuels, and Materials

    E-Print Network [OSTI]

    Delucchi, Mark

    2003-01-01T23:59:59.000Z

    by crediting against full fuel cycle emissions from theuse” process fuel -- is the full fuel cycle emission factor,where the full fuel cycle includes emissions from

  6. Used Nuclear Fuel Loading and Structural Performance Under Normal Conditions of Transport - Modeling, Simulation and Experimental Integration RD&D Plan

    SciTech Connect (OSTI)

    Adkins, Harold E. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States)

    2013-04-01T23:59:59.000Z

    Under current U.S. Nuclear Regulatory Commission regulation, it is not sufficient for used nuclear fuel (UNF) to simply maintain its integrity during the storage period, it must maintain its integrity in such a way that it can withstand the physical forces of handling and transportation associated with restaging the fuel and moving it to treatment or recycling facilities, or a geologic repository. Hence it is necessary to understand the performance characteristics of aged UNF cladding and ancillary components under loadings stemming from transport initiatives. Researchers would like to demonstrate that enough information, including experimental support and modeling and simulation capabilities, exists to establish a preliminary determination of UNF structural performance under normal conditions of transport (NCT). This research, development and demonstration (RD&D) plan describes a methodology, including development and use of analytical models, to evaluate loading and associated mechanical responses of UNF rods and key structural components. This methodology will be used to provide a preliminary assessment of the performance characteristics of UNF cladding and ancillary components under rail-related NCT loading. The methodology couples modeling and simulation and experimental efforts currently under way within the Used Fuel Disposition Campaign (UFDC). The methodology will involve limited uncertainty quantification in the form of sensitivity evaluations focused around available fuel and ancillary fuel structure properties exclusively. The work includes collecting information via literature review, soliciting input/guidance from subject matter experts, performing computational analyses, planning experimental measurement and possible execution (depending on timing), and preparing a variety of supporting documents that will feed into and provide the basis for future initiatives. The methodology demonstration will focus on structural performance evaluation of Westinghouse WE 17×17 pressurized water reactor fuel assemblies with a discharge burnup range of 30-58 GWd/MTU (assembly average), loaded in a representative high-capacity (?32 fuel rod assemblies) transportation package. Evaluations will be performed for representative normal conditions of rail transport involving a rail conveyance capable of meeting the Association of American Railroads (AAR) S-2043 specification. UNF modeling is anticipated to be defined to the pellet-cladding level and take in to account influences associated with spacer grids, intermediate fluid mixers, and control components. The influence of common degradation issues such as ductile-to-brittle-transition will also be accounted for. All model development and analysis will be performed with commercially available software packages exclusively. Inputs and analyses will be completely documented, all supporting information will be traceable, and bases will be defendable so as to be most useful to the U.S. Department of Energy community and mission. The expected completion date is the end of fiscal year (FY) 2013.

  7. Process Modeling Phase I Summary Report for the Advanced Gas Reactor Fuel Development and Qualification Program

    SciTech Connect (OSTI)

    Pannala, Sreekanth [ORNL; Daw, C Stuart [ORNL; Boyalakuntla, Dhanunjay S [ORNL; FINNEY, Charles E A [ORNL

    2006-09-01T23:59:59.000Z

    This report summarizes the results of preliminary work at Oak Ridge National Laboratory (ORNL) to demonstrate application of computational fluid dynamics modeling to the scale-up of a Fluidized Bed Chemical Vapor Deposition (FBCVD) process for nuclear fuels coating. Specifically, this work, referred to as Modeling Scale-Up Phase I, was conducted between January 1, 2006 and March 31, 2006 in support of the Advanced Gas Reactor (AGR) Program. The objective was to develop, demonstrate and "freeze" a version of ORNL's computational model of the TRI ISOtropic (TRISO) fuel-particle coating process that can be specifically used to assist coater scale-up activities as part of the production of AGR-2 fuel. The results in this report are intended to serve as input for making decisions about initiating additional FBCVD modeling work (referred to as Modeling Scale-Up Phase II) in support of AGR-2. The main computational tool used to implement the model is the general-purpose multiphase fluid-dynamics computer code known as MFIX (Multiphase Flow with Interphase eXchanges), which is documented in detail on the DOE-sponsored website http://www.mfix.org. Additional computational tools are also being developed by ORNL for post-processing MFIX output to efficiently summarize the important information generated by the coater simulations. The summarized information includes quantitative spatial and temporal measures (referred to as discriminating characteristics, or DCs) by which different coater designs and operating conditions can be compared and correlated with trends in product quality. The ORNL FBCVD modeling work is being conducted in conjunction with experimental coater studies at ORNL with natural uranium CO (NUCO) and surrogate fuel kernels. Data are also being obtained from ambient-temperature, spouted-bed characterization experiments at the University of Tennessee and theoretical studies of carbon and silicon carbide chemical vapor deposition kinetics at Iowa State University. Prior to the current scale-up activity, considerable effort has gone in to adapting the MFIX code to incorporate the unique features of fuel coating reactors and also in validating the resulting simulation features with experimental observations. Much of this work is documented in previous AGR reports and publications (Pannala et al., 2004, Pannala et al., 2005, Boyalakuntla et al., 2005a, Boyalakuntla et al., 2005b and Finney et al., 2005). As a result of the previous work described above, the ORNL coater model now has the capability for simulating full spatio-temporal details of the gas-particle hydrodynamics and gas-particle heat and mass transfer in the TRISO coater. This capability provides a great deal of information about many of the processes believed to control quality, but the model is not yet sufficiently developed to fully predict coating quality for any given coater design and/or set of operating conditions because the detailed chemical reaction kinetics needed to make the model fully predictive are not yet available. Nevertheless, the model at its current stage of development already provides the most comprehensive and detailed quantitative information available about gas flows, solid flows, temperatures, and species inside the coater during operation. This level of information ought to be highly useful in expediting the scale-up process (e.g., in correlating observations and minimizing the number of pilot-scale tests required). However, previous work had not yet demonstrated that the typical design and/or operating changes known to affect product quality at the lab scale could be clearly discriminated by the existing model. The Modeling Scale-Up Phase I work was initiated to produce such a demonstration, and two detailed examples are discussed in this report.

  8. Bulk viscosity and the phase transition of the linear sigma model

    E-Print Network [OSTI]

    Antonio Dobado; Juan M. Torres-Rincon

    2012-10-04T23:59:59.000Z

    In this work we deal with the critical behavior of the bulk viscosity in the linear sigma model (LSM) as an example of a system which can be treated by using different techniques. Starting from the Boltzmann-Uehling-Uhlenbeck equation we compute the bulk viscosity over entropy density of the LSM in the large-N limit. We search for a possible maximum of the bulk viscosity over entropy density at the critical temperature of the chiral phase transition. The information about this critical temperature, as well as the effective masses, is obtained from the effective potential. We find that the expected maximum (as a measure of the conformality loss) is absent in the large N in agreement with other models in the same limit. However, this maximum appears when, instead of the large-N limit, the Hartree approximation within the Cornwall-Jackiw-Tomboulis (CJT) formalism is used. Nevertheless, this last approach to the LSM does not give rise to the Goldstone theorem and also predicts a first order phase transition instead of the expected second order one. Therefore both, the large-N limit and the CJT-Hartree approximations, should be considered as complementary for the study of the critical behavior of the bulk viscosity in the LSM.

  9. Preliminary design report for modeling of hydrogen uptake in fuel rod cladding during severe accidents

    SciTech Connect (OSTI)

    Siefken, L.J.

    1998-08-01T23:59:59.000Z

    Preliminary designs are described for models of the interaction of Zircaloy and hydrogen and the consequences of this interaction on the behavior of fuel rod cladding during severe accidents. The modeling of this interaction and its consequences involves the modeling of seven processes: (1) diffusion of oxygen from the bulk gas into the boundary layer at the external cladding surface, (2) diffusion from the boundary layer into the oxide layer at the cladding external surface, (3) diffusion from the inner surface of the oxide layer into the metallic part of the cladding, (4) uptake of hydrogen in the event that the cladding oxide layer is dissolved in a steam-starved region, (5) embrittlement of cladding due to hydrogen uptake, (6) cracking of cladding during quenching due to its embrittlement and (7) release of hydrogen from the cladding after cracking of the cladding. An integral diffusion method is described for calculating the diffusion processes in the cladding. Experimental and theoretical results are presented that show the uptake of hydrogen in the event of dissolution of the oxide layer occurs rapidly and that show the release of hydrogen in the event of cracking of the cladding occurs rapidly. These experimental results are used as a basis for calculating the rate of hydrogen uptake and the rate of hydrogen release. The uptake of hydrogen is limited to the equilibrium solubility calculated by applying Sievert`s law. The uptake of hydrogen is an exothermic reaction that accelerates the heatup of a fuel rod. An embrittlement criteria is described that accounts for hydrogen and oxygen concentration and the extent of oxidation. A design is described for implementing the models for Zr-H interaction into the programming framework of the SCDAP/RELAP5 code. A test matrix is described for assessing the impact of the Zr-H interaction models on the calculated behavior of fuel rods in severe accident conditions.

  10. Modeling and simulation of hydrogen behavior in Zircaloy-4 fuel cladding

    SciTech Connect (OSTI)

    Jason D. Hales; Various

    2014-09-01T23:59:59.000Z

    As a result of corrosion during normal operation in nuclear reactors, hydrogen can enter the zirconium-alloy fuel cladding and precipitate as brittle hydride platelets, which can severely degrade the cladding ductility. Under a heterogeneous temperature distribution, hydrides tend to accumulate in the colder areas, creating local spots of degraded cladding that can favor crack initiation. Therefore, an estimation of the local hydride distribution is necessary to help predict the risk of cladding failure. The hydride distribution is governed by three competing phenomena. Hydrogen in solid solution diffuses under a concentration gradient due to Fick’s law and under a temperature gradient due to the Soret effect. Precipitation of the hydride platelets occurs once the hydrogen solubility limit is reached. A model of these phenomena was implemented in the 3D fuel performance code BISON in order to calculate the hydrogen distribution for arbitrary geometries, such as a nuclear fuel rod, and is now available for BISON users. Simulations have been performed on simple geometries to validate the model and its implementation. The simulations predict that before precipitation occurs, hydrogen tends to accumulate in the colder spots due to the Soret effect. Once the solubility limit is reached, hydrogen precipitates and forms a rim close to the outer edge of the cladding. The simulations also predict that the reactor shut down has little effect on already precipitated hydrides but causes the remaining hydrogen to precipitate homogeneously into hydrides.

  11. Improved Modeling and Understanding of Diffusion-Media Wettability on Polymer-Electrolyte-Fuel-Cell Performance

    SciTech Connect (OSTI)

    Weber, Adam

    2010-03-05T23:59:59.000Z

    A macroscopic-modeling methodology to account for the chemical and structural properties of fuel-cell diffusion media is developed. A previous model is updated to include for the first time the use of experimentally measured capillary pressure -- saturation relationships through the introduction of a Gaussian contact-angle distribution into the property equations. The updated model is used to simulate various limiting-case scenarios of water and gas transport in fuel-cell diffusion media. Analysis of these results demonstrate that interfacial conditions are more important than bulk transport in these layers, where the associated mass-transfer resistance is the result of higher capillary pressures at the boundaries and the steepness of the capillary pressure -- saturation relationship. The model is also used to examine the impact of a microporous layer, showing that it dominates the response of the overall diffusion medium. In addition, its primary mass-transfer-related effect is suggested to be limiting the water-injection sites into the more porous gas-diffusion layer.

  12. Autothermal reforming of gasoline for fuel cell applications : a control-oriented dynamic model.

    SciTech Connect (OSTI)

    Hu, Y.; Chmielewski, D. J.; Papadias, D.; Chemical Sciences and Engineering Division; Illinois Inst. of Tech.

    2008-11-05T23:59:59.000Z

    In this work, we develop a control-oriented, reduced order dynamic model of an autothermal reforming (ATR) reactor. The targeted application is within the on-board fuel-processing unit of a fuel cell vehicle. A previous effort has illustrated that a predictive-type controller may be required to achieve desired performance within this application. The objective of the current effort is to determine the existence of a reduced order model with enough speed and accuracy to meet the online computational demands of a predictive controller. Central to the model development is an approximation of reaction rates that achieve reasonable accuracy near the inlet while preserving the overall energy balance. The resulting scheme converts a partial differential equation model into a set of ordinary differential/algebraic equations and achieves nearly a 4 orders of magnitude improvement in computational speed while preserving most of the nonlinear characteristics of the original system. Such results give clear indication that the hurdle of computational viability can be overcome and opens the door for further development of a predictive controller for the ATR application.

  13. Modeling and Diagnostics of Fuel Cell Porous Media for Improving Water Transport

    SciTech Connect (OSTI)

    Allen, Jeff; M'edici, Ezequiel

    2011-07-01T23:59:59.000Z

    When a fuel cell is operating at high current density, water accumulation is a significant cause of performance and component degradation. Investigating the water transport inside the fuel cell is a challenging task due to opacity of the components, the randomness of the porous materials, and the difficulty in gain access to the interior for measurement due to the small dimensions of components. Numerical simulation can provide a good insight of the evolution of the water transport under different working condition. However, the validation of those simulations is remains an issue due the same experimental obstacles associated with in-situ measurements. The discussion herein will focus on pore-network modeling of the water transport on the PTL and the insights gained from simulations as well as in the validation technique. The implications of a recently published criterion to characterize PTL, based on percolation theory, and validate numerical simulation are discussed.

  14. Radiation Damage in Nuclear Fuel for Advanced Burner Reactors: Modeling and Experimental Validation

    SciTech Connect (OSTI)

    Jensen, Niels Gronbech; Asta, Mark; Ozolins, Nigel Browning'Vidvuds; de Walle, Axel van; Wolverton, Christopher

    2011-12-29T23:59:59.000Z

    The consortium has completed its existence and we are here highlighting work and accomplishments. As outlined in the proposal, the objective of the work was to advance the theoretical understanding of advanced nuclear fuel materials (oxides) toward a comprehensive modeling strategy that incorporates the different relevant scales involved in radiation damage in oxide fuels. Approaching this we set out to investigate and develop a set of directions: 1) Fission fragment and ion trajectory studies through advanced molecular dynamics methods that allow for statistical multi-scale simulations. This work also includes an investigation of appropriate interatomic force fields useful for the energetic multi-scale phenomena of high energy collisions; 2) Studies of defect and gas bubble formation through electronic structure and Monte Carlo simulations; and 3) an experimental component for the characterization of materials such that comparisons can be obtained between theory and experiment.

  15. Kinetic modelling of a surrogate diesel fuel applied to 3D auto-ignition in HCCI engines

    E-Print Network [OSTI]

    Bounaceur, Roda; Fournet, René; Battin-Leclerc, Frédérique; Jay, S; Da Cruz, A Pires

    2007-01-01T23:59:59.000Z

    The prediction of auto-ignition delay times in HCCI engines has risen interest on detailed chemical models. This paper described a validated kinetic mechanism for the oxidation of a model Diesel fuel (n-decane and ?-methylnaphthalene). The 3D model for the description of low and high temperature auto-ignition in engines is presented. The behavior of the model fuel is compared with that of n-heptane. Simulations show that the 3D model coupled with the kinetic mechanism can reproduce experimental HCCI and Diesel engine results and that the correct modeling of auto-ignition in the cool flame region is essential in HCCI conditions.

  16. A model of phase transitions in the system of electro-optical dipolar chromophores subject to an electric field

    E-Print Network [OSTI]

    A model of phase transitions in the system of electro-optical dipolar chromophores subject to an electric field Yuriy V. Pereverzev, Oleg V. Prezhdo,a) and Larry R. Dalton Department of Chemistry An analytical model for the nonlinear behavior of the electro-optic EO coefficient in chro- mophore

  17. Large-Signal HBT Model with Improved Collector Transit Time Formulation for GaAs and InP Technologies

    E-Print Network [OSTI]

    Asbeck, Peter M.

    mi': iaE Large-Signal HBT Model with Improved Collector Transit Time Formulation for GaAs and In large-signal HBT model which accurately accounts for the intricate hias dependence of collector delay collector delay function accounts for the variation of electron velocity with electric field

  18. Zero gravity two-phase flow regime transition modeling compared with data and relap5-3d predictions 

    E-Print Network [OSTI]

    Ghrist, Melissa Renee

    2009-05-15T23:59:59.000Z

    This thesis compares air/water two-phase flow regime transition models in zero gravity with data and makes recommendations for zero gravity models to incorporate into the RELAP5-3D thermal hydraulic computer code. Data from numerous researchers...

  19. Higgs boson resonance parameters and the finite temperature phase transition in a chirally invariant Higgs-Yukawa model

    E-Print Network [OSTI]

    John Bulava; Philip Gerhold; Karl Jansen; Jim Kallarackal; Attila Nagy

    2011-11-11T23:59:59.000Z

    We study a chirally invariant Higgs-Yukawa model regulated on a space-time lattice. We calculate Higgs boson resonance parameters and mass bounds for various values of the mass of the degenerate fermion doublet. Also, first results on the phase transition temperature are presented. In general, this model may be relevant for BSM scenarios with a heavy fourth generation of quarks.

  20. SOLID OXIDE FUEL CELL MANUFACTURING COST MODEL: SIMULATING RELATIONSHIPS BETWEEN PERFORMANCE, MANUFACTURING, AND COST OF PRODUCTION

    SciTech Connect (OSTI)

    Eric J. Carlson; Yong Yang; Chandler Fulton

    2004-04-20T23:59:59.000Z

    The successful commercialization of fuel cells will depend on the achievement of competitive system costs and efficiencies. System cost directly impacts the capital equipment component of cost of electricity (COE) and is a major contributor to the O and M component. The replacement costs for equipment (also heavily influenced by stack life) is generally a major contributor to O and M costs. In this project, they worked with the SECA industrial teams to estimate the impact of general manufacturing issues of interest on stack cost using an activities-based cost model for anode-supported planar SOFC stacks with metallic interconnects. An earlier model developed for NETL for anode supported planar SOFCs was enhanced by a linkage to a performance/thermal/mechanical model, by addition of Quality Control steps to the process flow with specific characterization methods, and by assessment of economies of scale. The 3-dimensional adiabatic performance model was used to calculate the average power density for the assumed geometry and operating conditions (i.e., inlet and exhaust temperatures, utilization, and fuel composition) based on publicly available polarizations curves. The SECA team provided guidance on what manufacturing and design issues should be assessed in this Phase I demonstration of cost modeling capabilities. They considered the impact of the following parameters on yield and cost: layer thickness (i.e., anode, electrolyte, and cathode) on cost and stress levels, statistical nature of ceramic material failure on yield, and Quality Control steps and strategies. In this demonstration of the capabilities of the linked model, only the active stack (i.e., anode, electrolyte, and cathode) and interconnect materials were included in the analysis. Factory costs are presented on an area and kilowatt basis to allow developers to extrapolate to their level of performance, stack design, materials, seal and system configurations, and internal corporate overheads and margin goals.

  1. Modeling of NO sensitization of IC engines surrogate fuels auto-ignition and combustion

    E-Print Network [OSTI]

    Anderlohr, Jörg; Bounaceur, Roda; Battin-Leclerc, Frédérique

    2009-01-01T23:59:59.000Z

    This paper presents a new chemical kinetic model developed for the simulation of auto-ignition and combustion of engine surrogate fuel mixtures sensitized by the presence of NOx. The chemical mechanism is based on the PRF auto-ignition model (n-heptane/iso-octane) of Buda et al. [1] and the NO/n-butane/n-pentane model of Glaude et al. [2]. The later mechanism has been taken as a reference for the reactions of NOx with larger alcanes (n-heptane, iso-octane). A coherent two components engine fuel surrogate mechanism has been generated which accounts for the influence of NOx on auto-ignition. The mechanism has been validated for temperatures between 700 K and 1100 K and pressures between 1 and 10 atm covering the temperature and pressure ranges characteristic of engine post-oxidation thermodynamic conditions. Experiments used for validation include jet stirred reactor conditions for species evolution as a function of temperature, as well as diesel HCCI engine experiments for auto-ignition delay time measurements...

  2. Vehicle Technologies Office: Transitioning the Transportation...

    Energy Savers [EERE]

    Transitioning the Transportation Sector - Exploring the Intersection of H2 Fuel Cell and Natural Gas Vehicles Vehicle Technologies Office: Transitioning the Transportation Sector -...

  3. Waste Classification based on Waste Form Heat Generation in Advanced Nuclear Fuel Cycles Using the Fuel-Cycle Integration and Tradeoffs (FIT) Model

    SciTech Connect (OSTI)

    Denia Djokic; Steven J. Piet; Layne F. Pincock; Nick R. Soelberg

    2013-02-01T23:59:59.000Z

    This study explores the impact of wastes generated from potential future fuel cycles and the issues presented by classifying these under current classification criteria, and discusses the possibility of a comprehensive and consistent characteristics-based classification framework based on new waste streams created from advanced fuel cycles. A static mass flow model, Fuel-Cycle Integration and Tradeoffs (FIT), was used to calculate the composition of waste streams resulting from different nuclear fuel cycle choices. This analysis focuses on the impact of waste form heat load on waste classification practices, although classifying by metrics of radiotoxicity, mass, and volume is also possible. The value of separation of heat-generating fission products and actinides in different fuel cycles is discussed. It was shown that the benefits of reducing the short-term fission-product heat load of waste destined for geologic disposal are neglected under the current source-based radioactive waste classification system , and that it is useful to classify waste streams based on how favorable the impact of interim storage is in increasing repository capacity.

  4. Waste Classification based on Waste Form Heat Generation in Advanced Nuclear Fuel Cycles Using the Fuel-Cycle Integration and Tradeoffs (FIT) Model - 13413

    SciTech Connect (OSTI)

    Djokic, Denia [Department of Nuclear Engineering, University of California - Berkeley, 4149 Etcheverry Hall, Berkeley, CA 94720-1730 (United States)] [Department of Nuclear Engineering, University of California - Berkeley, 4149 Etcheverry Hall, Berkeley, CA 94720-1730 (United States); Piet, Steven J.; Pincock, Layne F.; Soelberg, Nick R. [Idaho National Laboratory - INL, 2525 North Fremont Avenue, Idaho Falls, ID 83415 (United States)] [Idaho National Laboratory - INL, 2525 North Fremont Avenue, Idaho Falls, ID 83415 (United States)

    2013-07-01T23:59:59.000Z

    This study explores the impact of wastes generated from potential future fuel cycles and the issues presented by classifying these under current classification criteria, and discusses the possibility of a comprehensive and consistent characteristics-based classification framework based on new waste streams created from advanced fuel cycles. A static mass flow model, Fuel-Cycle Integration and Tradeoffs (FIT), was used to calculate the composition of waste streams resulting from different nuclear fuel cycle choices. This analysis focuses on the impact of waste form heat load on waste classification practices, although classifying by metrics of radiotoxicity, mass, and volume is also possible. The value of separation of heat-generating fission products and actinides in different fuel cycles is discussed. It was shown that the benefits of reducing the short-term fission-product heat load of waste destined for geologic disposal are neglected under the current source-based radioactive waste classification system, and that it is useful to classify waste streams based on how favorable the impact of interim storage is in increasing repository capacity. (authors)

  5. An Integrated Approach for Creating Model Diesel Fuels Ioannis P. Androulakis, Mark D. Weisel, Chang S. Hsu, Kuangnan Qian,

    E-Print Network [OSTI]

    Androulakis, Ioannis (Yannis)

    An Integrated Approach for Creating Model Diesel Fuels Ioannis P. Androulakis, Mark D. Weisel matter emissions in advanced diesel engines. This includes a sophisticated numerical optimization algorithm to formulate well-characterized diesel fuel blends and an analytical method to characterize diesel

  6. KINETIC MODELING OF A SURROGATE DIESEL FUEL APPLIED TO 3D AUTO-IGNITION IN HCCI ENGINES

    E-Print Network [OSTI]

    Paris-Sud XI, Université de

    KINETIC MODELING OF A SURROGATE DIESEL FUEL APPLIED TO 3D AUTO-IGNITION IN HCCI ENGINES R OF A SURROGATE DIESEL FUEL APPLIED TO 3D AUTO-IGNITION IN HCCI ENGINES INTRODUCTION Engines running on HCCI combustion mode (Homogeneous Charge Compression Ignition) have the potential to provide both diesel

  7. Using a Quasipotential Transformation for Modeling Diffusion Media inPolymer-Electrolyte Fuel Cells

    SciTech Connect (OSTI)

    Weber, Adam Z.; Newman, John

    2008-08-29T23:59:59.000Z

    In this paper, a quasipotential approach along with conformal mapping is used to model the diffusion media of a polymer-electrolyte fuel cell. This method provides a series solution that is grid independent and only requires integration along a single boundary to solve the problem. The approach accounts for nonisothermal phenomena, two-phase flow, correct placement of the electronic potential boundary condition, and multilayer media. The method is applied to a cathode diffusion medium to explore the interplay between water and thermal management and performance, the impact of the rib-to-channel ratio, and the existence of diffusion under the rib and flooding phenomena.

  8. Impact of subgrid-scale radiative heating variability on the stratocumulus-to-trade cumulus transition in climate models

    SciTech Connect (OSTI)

    Xiao, Heng; Gustafson, William I.; Wang, Hailong

    2014-04-29T23:59:59.000Z

    Subgrid-scale interactions between turbulence and radiation are potentially important for accurately reproducing marine low clouds in climate models. To better understand the impact of these interactions, the Weather Research and Forecasting (WRF) model is configured for large eddy simulation (LES) to study the stratocumulus-to-trade cumulus (Sc-to-Cu) transition. Using the GEWEX Atmospheric System Studies (GASS) composite Lagrangian transition case and the Atlantic Trade Wind Experiment (ATEX) case, it is shown that the lack of subgrid-scale turbulence-radiation interaction, as is the case in current generation climate models, accelerates the Sc-to-Cu transition. Our analysis suggests that in cloud-topped boundary layers subgrid-scale turbulence-radiation interactions contribute to stronger production of temperature variance, which in turn leads to stronger buoyancy production of turbulent kinetic energy and helps to maintain the Sc cover.

  9. Thermal performance sensitivity studies in support of material modeling for extended storage of used nuclear fuel

    SciTech Connect (OSTI)

    Cuta, Judith M.; Suffield, Sarah R.; Fort, James A.; Adkins, Harold E.

    2013-08-15T23:59:59.000Z

    The work reported here is an investigation of the sensitivity of component temperatures of a storage system, including fuel cladding temperatures, in response to age-related changes that could degrade the design-basis thermal behavior of the system. Three specific areas of interest were identified for this study. • degradation of the canister backfill gas from pure helium to a mixture of air and helium, resulting from postulated leakage due to stress corrosion cracking (SCC) of canister welds • changes in surface emissivity of system components, resulting from corrosion or other aging mechanisms, which could cause potentially significant changes in temperatures and temperature distributions, due to the effect on thermal radiation exchange between components • changes in fuel and basket temperatures due to changes in fuel assembly position within the basket cells in the canister The purpose of these sensitivity studies is to provide a realistic example of how changes in the physical properties or configuration of the storage system components can affect temperatures and temperature distributions. The magnitudes of these sensitivities can provide guidance for identifying appropriate modeling assumptions for thermal evaluations extending long term storage out beyond 50, 100, 200, and 300 years.

  10. Fundamental Study of the Oxidation Characteristics and Pollutant Emissions of Model Biodiesel Fuels

    SciTech Connect (OSTI)

    Feng, Q.; Wang, Y. L.; Egolfopoulos, Fokion N.; Tsotsis, T. T.

    2010-01-01T23:59:59.000Z

    In this study, the oxidation characteristics of biodiesel fuels are investigated with the goal of contributing toward the fundamental understanding of their combustion characteristics and evaluating the effect of using these alternative fuels on engine performance as well as on the environment. The focus of the study is on pure fatty acid methyl-esters (FAME,) that can serve as surrogate compounds for real biodiesels. The experiments are conducted in the stagnation-flow configuration, which allows for the systematic evaluation of fundamental combustion and emission characteristics. In this paper, the focus is primarily on the pollutant emission characteristics of two C{sub 4} FAMEs, namely, methyl-butanoate and methyl-crotonate, whose behavior is compared with that of n-butane and n-pentane. To provide insight into the mechanisms of pollutant formation for these fuels, the experimental data are compared with computed results using a model with consistent C{sub 1}?C{sub 4} oxidation and NO{sub x} formation kinetics.

  11. Modelling and Verification of Automated Transit Systems, Using Timed Automata, Invariants and

    E-Print Network [OSTI]

    Lynch, Nancy

    and gates, steam boiler control) appear in [8, 10]. Briefly, a timed automaton is a labelled transition

  12. Modelling and Veri cation of Automated Transit Systems, using Timed Automata, Invariants and

    E-Print Network [OSTI]

    Lynch, Nancy

    and gates, steam boiler control) appear in 8, 10]. Brie y, a timed automaton is a labelled transition system

  13. Matrix Product State and Quantum Phase Transitions in the One-Dimensional Extended Quantum Compass Model

    E-Print Network [OSTI]

    Guang-Hua Liu; Wei Li; Wen-Long You; Guang-Shan Tian; Gang Su

    2012-06-02T23:59:59.000Z

    The matrix product state (MPS) is utilized to study the ground state properties and quantum phase transitions (QPTs) of the one-dimensional quantum compass model (QCM). The MPS wavefunctions are argued to be very efficient descriptions of QCM ground states, and are numerically determined by imaginary time projections. The ground state energy, correlations, quantum entanglement and its spectrum, local and nonlocal order parameters, etc., are calculated and studied in details. It is revealed that the bipartite and block entanglement entropies, as well as the nearest neighbor correlation functions can be used to detect the second-order QPTs, but not the first-order ones, while fidelity detections can recognize both. The entanglement spectrum is extracted from the MPS wavefunction, and found to be doubly degenerate in disordered phases of QCM, where non-local string order parameters exist. Moreover, with linearized tensor renormalization group method, the specific heat curves are evaluated and their low temperature behaviors are investigated.

  14. Transition from static to kinetic friction: Insights from a 2D model

    E-Print Network [OSTI]

    Trømborg, Jørgen; Amundsen, David Skålid; Thøgersen, Kjetil; Malthe-Sørenssen, Anders

    2013-01-01T23:59:59.000Z

    We describe a 2D spring-block model for the transition from static to kinetic friction at an elastic slider/rigid substrate interface obeying a minimalistic friction law (Amontons-Coulomb). By using realistic boundary conditions, a number of previously unexplained experimental results on precursory micro-slip fronts are successfully reproduced. From the analysis of the interfacial stresses, we derive a prediction for the evolution of the precursor length as a function of the applied loads, as well as an approximate relationship between microscopic and macroscopic friction coefficients. We show that the stress build-up due to both elastic loading and micro-slip-related relaxations depend only weakly on the underlying shear crack propagation dynamics. Conversely, crack speed depends strongly on both the instantaneous stresses and the friction coefficients, through a non-trivial scaling parameter.

  15. Size dependence, stability, and a transition to buckling in model reverse bilayers

    E-Print Network [OSTI]

    J. Stecki

    2006-07-03T23:59:59.000Z

    Molecular Dynamics simulations of a model bilayer made of surfactant dimers in a Lennard-Jones solvent are reported for three sizes of the systems up to an area of $100\\sigma \\times 100\\sigma$ and for a large interval of specific areas:from hole formation under tension to the floppy state of a compressed bilayer. The transition to the floppy state appears quite abrupt and discontinuous; in the floppy state the lateral tension is negative. Lateral tension and the structure factor were determined for all 3 sizes and all areas; the apparent rigidity constant and apparent surface tension are determined and correlated with the specific area and the finite size. The replacement of the $1/q^2$ capillary-wave divergence by a pole is accounted for and explained. The derivative of the lateral tension jumps from a high value in a flat bilayer to a low value in the floppy, rough, and buckling state, where the tension itself is negative.

  16. Phase transitions in a reaction-diffusion model on a line with boundaries

    SciTech Connect (OSTI)

    Khorrami, Mohammad, E-mail: mamwad@mailaps.org; Aghamohammadi, Amir, E-mail: mohamadi@alzahra.ac.ir [Department of Physics, Alzahra University, Tehran 19938-93973 (Iran, Islamic Republic of)] [Department of Physics, Alzahra University, Tehran 19938-93973 (Iran, Islamic Republic of)

    2014-03-15T23:59:59.000Z

    A one-dimensional model on a line of length L is investigated, which involves particle diffusion as well as single particle annihilation. There are also creation and annihilation at the boundaries. The static and dynamical behaviors of the system are studied. It is seen that the system could exhibit a dynamical phase transition. For small drift velocities, the relaxation time does not depend on the absorption rates at the boundaries. This is the fast phase. For large velocities, the smaller of the absorption rates at boundaries enter the relaxation rate and makes it longer. This is the slow phase. Finally, the effect of a random particle creation in the bulk is also investigated.

  17. Critical analysis of plume containment modeling in a thin heterogeneous unconfined aquifer: application to a bulk fuel storage terminal

    E-Print Network [OSTI]

    Mejia, Karl Edward

    1997-01-01T23:59:59.000Z

    The reported hydrocarbon contamination and subsequent consultant work at a bulk fuel storage terminal has instigated the need to critically analyze modeling techniques in thin, heterogeneous, unconfined aquifers. This study provides an aquifer...

  18. 2015 Hydrogen Student Design Contest Challenges Students to Develop Innovative Hydrogen Fueling Station Business and Financing Models

    Broader source: Energy.gov [DOE]

    The Hydrogen Education Foundation announced the 11th annual Hydrogen Student Design Contest, which will challenge student teams to develop business and financing models for hydrogen fueling stations. Registration for the Contest is open until January 16, 2015.

  19. Integrated fuel performance and thermal-hydraulic sub-channel models for analysis of sodium fast reactors

    E-Print Network [OSTI]

    Fricano, Joseph William

    2012-01-01T23:59:59.000Z

    Sodium Fast Reactors (SFR) show promise as an effective way to produce clean safe nuclear power while properly managing the fuel cycle. Accurate computer modeling is an important step in the design and eventual licensing ...

  20. Critical analysis of plume containment modeling in a thin heterogeneous unconfined aquifer: application to a bulk fuel storage terminal 

    E-Print Network [OSTI]

    Mejia, Karl Edward

    1997-01-01T23:59:59.000Z

    The reported hydrocarbon contamination and subsequent consultant work at a bulk fuel storage terminal has instigated the need to critically analyze modeling techniques in thin, heterogeneous, unconfined aquifers. This study provides an aquifer...