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1

Lessons Learned from Alternative Transportation Fuels: Modeling Transition Dynamics  

Alternative Fuels and Advanced Vehicles Data Center (EERE)

Lessons Learned from Lessons Learned from Alternative Transportation Fuels: Modeling Transition Dynamics C. Welch Technical Report NREL/TP-540-39446 February 2006 Lessons Learned from Alternative Transportation Fuels: Modeling Transition Dynamics C. Welch Prepared under Task Nos. HS04.2000 and HS06.1002 Technical Report NREL/TP-540-39446 February 2006 National Renewable Energy Laboratory 1617 Cole Boulevard, Golden, Colorado 80401-3393 303-275-3000 * www.nrel.gov Operated for the U.S. Department of Energy Office of Energy Efficiency and Renewable Energy by Midwest Research Institute * Battelle Contract No. DE-AC36-99-GO10337 NOTICE This report was prepared as an account of work sponsored by an agency of the United States government. Neither the United States government nor any agency thereof, nor any of their employees, makes any

2

Lessons Learned from Alternative Transportation Fuels: Modeling Transition Dynamics  

DOE Green Energy (OSTI)

Report focuses on understanding how analytical system modeling and data from AFV experiences could improve our understanding of the dynamic forces governing the transition to a hydrogen future.

Welch, C.

2006-02-01T23:59:59.000Z

3

Alternative fuel transit buses  

DOE Green Energy (OSTI)

The National Renewable Energy Laboratory (NREL) is a U.S. Department of Energy (DOE) national laboratory; this project was funded by DOE. One of NREL`s missions is to objectively evaluate the performance, emissions, and operating costs of alternative fuel vehicles so fleet managers can make informed decisions when purchasing them. Alternative fuels have made greater inroads into the transit bus market than into any other. Each year, the American Public Transit Association (APTA) surveys its members on their inventory and buying plans. The latest APTA data show that about 4% of the 50,000 transit buses in its survey run on an alternative fuel. Furthermore, 1 in 5 of the new transit buses that members have on order are alternative fuel buses. This program was designed to comprehensively and objectively evaluate the alternative fuels in use in the industry.

Motta, R.; Norton, P.; Kelly, K. [and others

1996-10-01T23:59:59.000Z

4

Alternative Fuel Transit Buses  

Alternative Fuels and Advanced Vehicles Data Center (EERE)

35th St. Craig Ave. Alt Blvd. Colucci Pkwy. Final Results from the National Renewable Energy Laboratory Vehicle Evaluation Program Final Results from the National Renewable Energy Laboratory Vehicle Evaluation Program N T Y A U E O F E N E R G D E P A R T M E N I T E D S T A T S O F A E R I C M Produced for the U.S. Department of Energy (DOE) by the National Renewable Energy Laboratory (NREL), a U.S. DOE national laboratory Transit Buses Alternative Fuel Alternative Fuel Final Results from the National Renewable Energy Laboratory (NREL) Vehicle Evaluation Program by Robert Motta, Paul Norton, and Kenneth Kelly, NREL Kevin Chandler, Battelle Leon Schumacher, University of Missouri Nigel Clark,West Virginia University October 1996 The authors wish to thank all the transit agencies that participated in this program.

5

Alternative Fuels at AC Transit  

NLE Websites -- All DOE Office Websites (Extended Search)

Alternative Fuels at AC Transit Alternative Fuels at AC Transit Speaker(s): Jaimie Levin Date: November 1, 2011 - 12:00pm Location: 90-3122 Seminar Host/Point of Contact: Eve Edelson Mr. Levin will discuss AC Transit's range of environmental technology initiatives, including: zero emission fuel cell transit buses; state-of-the-art, high-capacity, hydrogen fueling stations; solar energy systems; and stationary solid oxide fuel cell power generators. AC Transit has the largest fleet of fuel cell buses in the United States, featuring fuel cell systems with more than 10,000 hours of continuous operation without any failures or power degradation. Their fuel cell fleet has logged more than 400,000 miles of service and carried in excess of one million passengers. Come hear what AC Transit has learned, where they're headed,

6

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

E-Print Network (OSTI)

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 ...

Supple, Derek R. (Derek Richard)

2007-01-01T23:59:59.000Z

7

Alternative Fuels Data Center: Mass Transit  

Alternative Fuels and Advanced Vehicles Data Center (EERE)

Mass Transit to Mass Transit to someone by E-mail Share Alternative Fuels Data Center: Mass Transit on Facebook Tweet about Alternative Fuels Data Center: Mass Transit on Twitter Bookmark Alternative Fuels Data Center: Mass Transit on Google Bookmark Alternative Fuels Data Center: Mass Transit on Delicious Rank Alternative Fuels Data Center: Mass Transit on Digg Find More places to share Alternative Fuels Data Center: Mass Transit on AddThis.com... More in this section... Idle Reduction Parts & Equipment Maintenance Driving Behavior Fleet Rightsizing System Efficiency Ridesharing Mass Transit Active Transit Multi-Modal Transportation Telework Mass Transit Passenger-Miles per Gallon Passenger-miles per gallon (pmpg) is a metric for comparing mass transit and rideshare with typical passenger vehicle travel. Transportation system

8

Alternative Fuels Data Center: Active Transit  

Alternative Fuels and Advanced Vehicles Data Center (EERE)

Active Transit to Active Transit to someone by E-mail Share Alternative Fuels Data Center: Active Transit on Facebook Tweet about Alternative Fuels Data Center: Active Transit on Twitter Bookmark Alternative Fuels Data Center: Active Transit on Google Bookmark Alternative Fuels Data Center: Active Transit on Delicious Rank Alternative Fuels Data Center: Active Transit on Digg Find More places to share Alternative Fuels Data Center: Active Transit on AddThis.com... More in this section... Idle Reduction Parts & Equipment Maintenance Driving Behavior Fleet Rightsizing System Efficiency Ridesharing Mass Transit Active Transit Multi-Modal Transportation Telework Active Transit Photo of people riding bikes. Active transit is human-powered transportation such as biking and walking. Active transportation eliminates vehicle miles traveled altogether, so this

9

Fuel Cells Technology Transit | Open Energy Information  

Open Energy Info (EERE)

Technology Transit Technology Transit Jump to: navigation, search Name Fuel Cells Technology Transit Place Clearwater, Florida Zip 33767 Sector Hydro, Hydrogen Product Involved in the development and research of energy models on Hydrogen Energy Fuel Cell within the local and national arena. Coordinates 42.172132°, -98.189096° Loading map... {"minzoom":false,"mappingservice":"googlemaps3","type":"ROADMAP","zoom":14,"types":["ROADMAP","SATELLITE","HYBRID","TERRAIN"],"geoservice":"google","maxzoom":false,"width":"600px","height":"350px","centre":false,"title":"","label":"","icon":"","visitedicon":"","lines":[],"polygons":[],"circles":[],"rectangles":[],"copycoords":false,"static":false,"wmsoverlay":"","layers":[],"controls":["pan","zoom","type","scale","streetview"],"zoomstyle":"DEFAULT","typestyle":"DEFAULT","autoinfowindows":false,"kml":[],"gkml":[],"fusiontables":[],"resizable":false,"tilt":0,"kmlrezoom":false,"poi":true,"imageoverlays":[],"markercluster":false,"searchmarkers":"","locations":[{"text":"","title":"","link":null,"lat":42.172132,"lon":-98.189096,"alt":0,"address":"","icon":"","group":"","inlineLabel":"","visitedicon":""}]}

10

Alternative fuel transit buses: The Pierce Transit Success Story  

DOE Green Energy (OSTI)

The Pierce transit program for operating mass transit buses on compressed natural gas (CNG) is described. Cost, reliability, fuel efficiency, emission of combustion products, and future trends are discussed.

NONE

1996-10-01T23:59:59.000Z

11

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

DOE Green Energy (OSTI)

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.

Chandler, K.; Eudy, L.

2008-10-01T23:59:59.000Z

12

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

DOE Green Energy (OSTI)

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.

Chandler, K.; Eudy, L.

2007-03-01T23:59:59.000Z

13

Checklist for transition to new highway fuel(s).  

DOE Green Energy (OSTI)

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.

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

2011-12-15T23:59:59.000Z

14

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

Open Energy Info (EERE)

This webside provide Tools & Calculators like Public Transit In Your Community, Fuel Saving Calculator, Carbon saving calculator, Transit Savings Report and transit benefits...

15

Vehicle Technologies Office: Transit Buses: Today's Pioneers in Fuel Cell  

NLE Websites -- All DOE Office Websites (Extended Search)

Transit Buses: Today's Transit Buses: Today's Pioneers in Fuel Cell Transportation to someone by E-mail Share Vehicle Technologies Office: Transit Buses: Today's Pioneers in Fuel Cell Transportation on Facebook Tweet about Vehicle Technologies Office: Transit Buses: Today's Pioneers in Fuel Cell Transportation on Twitter Bookmark Vehicle Technologies Office: Transit Buses: Today's Pioneers in Fuel Cell Transportation on Google Bookmark Vehicle Technologies Office: Transit Buses: Today's Pioneers in Fuel Cell Transportation on Delicious Rank Vehicle Technologies Office: Transit Buses: Today's Pioneers in Fuel Cell Transportation on Digg Find More places to share Vehicle Technologies Office: Transit Buses: Today's Pioneers in Fuel Cell Transportation on AddThis.com... Transit Buses: Today's Pioneers in Fuel Cell Transportation

16

Alternative Fuels and Vehicles Training Resource Guide for Transit Districts  

DOE Green Energy (OSTI)

Resource guide features training courses about alternative fuels and vehicles related training courses that are available to transit agency employees.

Not Available

2003-04-01T23:59:59.000Z

17

Fuel Modeling I  

Science Conference Proceedings (OSTI)

Mar 4, 2013 ... Integrated Computational Modeling of Materials for Nuclear Energy: Fuel ... in the incorporation of rare gas fission products such as Kr and Xe.

18

Modeling & Simulation - Fuel Cells  

NLE Websites -- All DOE Office Websites (Extended Search)

GCTool Computer Model Helps Focus Fuel Cell Vehicle Research Somewhere near Detroit, an automotive engineer stares at the ceiling, wondering how to squeeze 1% more efficiency out...

19

Nuclear Fuels - Modeling  

Science Conference Proceedings (OSTI)

Mar 12, 2012... for the Current and Advanced Nuclear Reactors: Nuclear Fuels - Modeling .... Using density functional theory (DFT), we have predicted that...

20

Transitioning from Fuel Cells to Redox Flow Cells  

NLE Websites -- All DOE Office Websites (Extended Search)

Transitioning From Fuel Cells to Redox Transitioning From Fuel Cells to Redox Flow Cells T. Zawodzinski and Matt Mench University of Tennessee and ORNL Managed by UT-Battelle for the Department of Energy 2 Acknowledgments $$ DOE-OE EPRI GCEP NSF EPSCOR (TN SCORE) UTK Governor's Chair Fund Partner in Crime Matt Mench Managed by UT-Battelle for the Department of Energy 'Peeling the Onion' Personalized History of PEM Fuel Cells We May Recapitulate This for RFBs Catalysis Test System * Small Single Cell * Large Single Cell * Stack * System Layers of the Onion Hot Topic du Jour * Water Management, Membranes * Late '80's, early '90's * Reformate Tolerance, DMFC's * Mid '90's * High Temp Membranes * Late '90's * Durability * Early '00's Modeling * Membrane/ Water * Cathode * Impedance

Note: This page contains sample records for the topic "fuels modeling transition" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


21

Alternative Fuels Data Center: Transit Emissions and Energy Reduction  

Alternative Fuels and Advanced Vehicles Data Center (EERE)

Transit Emissions and Transit Emissions and Energy Reduction Assistance to someone by E-mail Share Alternative Fuels Data Center: Transit Emissions and Energy Reduction Assistance on Facebook Tweet about Alternative Fuels Data Center: Transit Emissions and Energy Reduction Assistance on Twitter Bookmark Alternative Fuels Data Center: Transit Emissions and Energy Reduction Assistance on Google Bookmark Alternative Fuels Data Center: Transit Emissions and Energy Reduction Assistance on Delicious Rank Alternative Fuels Data Center: Transit Emissions and Energy Reduction Assistance on Digg Find More places to share Alternative Fuels Data Center: Transit Emissions and Energy Reduction Assistance on AddThis.com... More in this section... Federal State Advanced Search All Laws & Incentives Sorted by Type

22

A smooth transition to hydrogen transportation fuel  

SciTech Connect

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.

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

1995-04-14T23:59:59.000Z

23

VISION: Verifiable Fuel Cycle Simulation Model  

Science Conference Proceedings (OSTI)

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 Initiatives 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.

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

2009-04-01T23:59:59.000Z

24

Alameda-Contra Costa Transit District Fuel Cell Transit Buses: Evaluation Results Update  

DOE Green Energy (OSTI)

This report is an update to the 2007 preliminary results report on hydrogen fuel cell and diesel buses operating at Alameda-Contra Costa Transit District.

Chandler, K.; Eudy, L.

2007-10-01T23:59:59.000Z

25

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

DOE Green Energy (OSTI)

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.

Chandler, K.; Eudy, L.

2008-07-01T23:59:59.000Z

26

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

DOE Green Energy (OSTI)

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.

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

2000-11-07T23:59:59.000Z

27

Alternative Fuels in Public Transit: A Match Made on the Road  

DOE Green Energy (OSTI)

Brochure addressing alternative fuel modes of transportation for public transit, challenges, fuels, infrastructure, cast studies, guidance, and resources.

Not Available

2002-03-01T23:59:59.000Z

28

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

DOE Green Energy (OSTI)

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.

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

2009-10-01T23:59:59.000Z

29

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

DOE Green Energy (OSTI)

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).

Chandler, K.; Eudy, L.

2009-01-01T23:59:59.000Z

30

FCCU transition-probability model  

Science Conference Proceedings (OSTI)

The adequacy of the use of transition-probability matrices for modelling fluidised catalyst cracker unit emissions was investigated. A number of different-sized matrices that modelled the processes of attrition and agglomeration were used, and it was ... Keywords: Agglomeration, Attrition, Probability matrix

Robbie J. Dixon; Maki Matsuka; Roger D. Braddock; Josh M. Whitcombe; Igor E. Agranovski

2007-02-01T23:59:59.000Z

31

Designing New Transit Bus Garages to be Fuel Flexible  

Alternative Fuels and Advanced Vehicles Data Center (EERE)

Designing New Transit Bus Garages to be Fuel Flexible Prepared By: Marathon Technical Services Six Venus Crescent P.O. Box 318 Heidelberg, Ontario, Canada N0B1Y0 Telephone: 519-699-9250 May 12, 2006 ______________________________________________________________________________ DESIGNING NEW TRANSIT BUS GARAGES TO BE FUEL FLEXIBLE Background Information Before discussing the building design features that are recommended for CNG and GH2 buses, it is important to understand what makes these fuels different from gasoline or diesel. The items below summarize the basic differences between the properties of gaseous and liquid fuels that influence the building design changes: 1. Natural Gas and Hydrogen are both lighter-than-air and in gaseous form at atmospheric

32

Modelling societal transitions with agent transformation  

Science Conference Proceedings (OSTI)

Transition models explain long-term and large-scale processes fundamentally changing the structure of a societal system. Our concern is that most transition models are too static. Although they capture a move of focus from static equilibria to transitions ... Keywords: Agent-based modelling, Integrated sustainability assessment, Societal transitions

Michel Schilperoord; Jan Rotmans; Noam Bergman

2008-12-01T23:59:59.000Z

33

Transition Metal Sulfide Electrocatalysts for PEM Fuel Cells  

NLE Websites -- All DOE Office Websites (Extended Search)

Transition Metal Sulfide Transition Metal Sulfide Electrocatalysts for PEM Fuel Cells Hua Zhang 1 , Ysmael Verde-Gómez 1 and Allan J. Jacobson 1 Alejandra Ramirez 2 and Russell R. Chianelli 2 1 Department of Chemistry, University of Houston Houston, TX 77204 2 Materials Research and Technology Institute, University of Texas at El Paso, El Paso, TX 79968 Transition Metal Sulfide Electrocatalysts for PEM Fuel Cells Hua Zhang 1 , Ysmael Verde-Gómez 1 and Allan J. Jacobson 1 Alejandra Ramirez 2 and Russell R. Chianelli 2 1 Department of Chemistry, University of Houston Houston, TX 77204 2 Materials Research and Technology Institute, University of Texas at El Paso, El Paso, TX 79968 March 21, 2003 Objectives ¾ Investigate non-platinum electro-catalysts with CO tolerance ¾ Focus on transition metal sulfides as electro-catalysts

34

Update from the NREL Alternative Fuel Transit Bus Evaluation Program  

DOE Green Energy (OSTI)

The object of this project, which is supported by the U.S. Department of Energy (DOE) through the National Renewable Energy Laboratory (NREL), is to provide a comprehensive comparison of heavy-duty urban transit buses operating on alternative fuels and diesel fuel. Final reports from this project were produced in 1996 from data collection and evaluation of 11 transit buses from eight transit sites. With the publication of these final reports, three issues were raised that needed further investigation: (1) the natural gas engines studied were older, open-loop control engines; (2) propane was not included in the original study; and (3) liquefied natural gas (LNG) was found to be in the early stages of deployment in transit applications. In response to these three issues, the project has continued by emissions testing newer natural gas engines and adding two new data collection sites to study the newer natural gas technology and specifically to measure new technology LNG buses.

Chandler, K. (Battelle); Norton, P. (National Renewable Energy Laboratory); Clark, N. (West Virginia University)

1999-05-01T23:59:59.000Z

35

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

DOE Green Energy (OSTI)

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.

Chandler, K.; Eudy, L.

2010-01-01T23:59:59.000Z

36

Transitioning to a Hydrogen Future: Learning from the Alternative Fuels Experience  

DOE Green Energy (OSTI)

This paper assesses relevant knowledge within the alternative fuels community and recommends transitional strategies and tactics that will further the hydrogen transition in the transportation sector.

Melendez, M.

2006-02-01T23:59:59.000Z

37

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

DOE Green Energy (OSTI)

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

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

2008-12-01T23:59:59.000Z

38

Rethinking hydrogen fueling insights from delivery modeling.  

SciTech Connect

Over the past century gasoline fueling has evolved from being performed by a variety of informal, diverse methods to being performed through the use of a standardized, highly automated system that exploits the fuel's benefits and mitigates its hazards. Any effort to transition to another fuel with different properties--with both advantages and disadvantages--must make similar adjustments. This paper discusses the existing gasoline refueling infrastructure and its evolution. It then describes the hydrogen delivery scenario analysis model, an Excel-based tool that calculates the levelized cost of delivering hydrogen from a central production facility to a vehicle by the use of currently available technologies and a typical profile of vehicle use and fueling demand. The results are shown for a status quo, or gasoline-centric case, in which demand reflects the current gasoline-based system and supply responds accordingly, and a hydrogen-centric case, in which some of those patterns are altered. The paper highlights fueling requirements that are particularly problematic for hydrogen and concludes with a discussion of alternative fueling paradigms.

Mintz, M.; Elgowainy, A.; Gardiner, M.; Energy Systems; U. S. DOE

2009-01-01T23:59:59.000Z

39

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

DOE Green Energy (OSTI)

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.

Eudy, L.; Chandler, K.

2006-03-01T23:59:59.000Z

40

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

DOE Green Energy (OSTI)

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

Chandler, K.; Eudy, L.

2006-11-01T23:59:59.000Z

Note: This page contains sample records for the topic "fuels modeling transition" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


41

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

DOE Green Energy (OSTI)

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.

Chandler, K.; Eudy, L.

2009-01-01T23:59:59.000Z

42

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

DOE Green Energy (OSTI)

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.

Eudy, L.; Chandler, K.

2009-08-01T23:59:59.000Z

43

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

DOE Green Energy (OSTI)

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.

Chandler, K.; Eudy, L.

2009-05-01T23:59:59.000Z

44

Fuel Cell Technologies Office: DOE Hydrogen Transition Analysis...  

NLE Websites -- All DOE Office Websites (Extended Search)

Inc. Overview of NEMS-H2, Version 1.0 (PDF 294 KB), Frances Wood, OnLocation, Inc. Agent-Based Modeling and Simulation for Hydrogen Transition Analysis (PDF 515 KB),...

45

Fuel Reliability Program: BWR Fuel Crud Modeling  

Science Conference Proceedings (OSTI)

Deposition of BWR reactor system corrosion products (crud) on operating fuel rods has resulted in performance limiting conditions in a limited number of cases. The operational impact can include unplanned, or increased frequency of fuel inspections, fuel failure and associated radiological consequences, operational restrictions including core power derate and/or forced shutdowns to remove failed fuel, premature discharge of individual bundles or entire reloads, and undesirable core design restrictions. T...

2010-12-23T23:59:59.000Z

46

Energy Transition Model | Open Energy Information  

Open Energy Info (EERE)

Energy Transition Model Energy Transition Model Jump to: navigation, search Tool Summary LAUNCH TOOL Name: Energy Transition Model Agency/Company /Organization: Quintel Intelligence Sector: Energy Topics: Resource assessment Resource Type: Maps, Software/modeling tools User Interface: Website Website: energytransitionmodel.com/ Country: Netherlands Web Application Link: energytransitionmodel.com/ Cost: Free OpenEI Keyword(s): International UN Region: Western Europe References: webservice-energy.org[1] MINES Energy Transition Model[2] Logo: Energy Transition Model The Energy Transition Model is an independent, comprehensive and fact-based energy model that is used by governments, corporations, NGOs and educators in various countries. It is backed by more than 20 partners. There are

47

Fuel Modeling II  

Science Conference Proceedings (OSTI)

Mar 4, 2013 ... Integrated Computational Modeling of Materials for Nuclear Energy: ... Continuum Theory of Defects and Materials Response to Irradiation:...

48

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

DOE Green Energy (OSTI)

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.

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

2011-11-01T23:59:59.000Z

49

Modelling Accretion in Transitional Disks  

E-Print Network (OSTI)

Transitional disks are protoplanetary disk around young stars that display inner holes in the dust distribution within a few AU, which is accompanied nevertheless by some gas accretion onto the central star. These cavities could possibly be created by the presence of one or more massive planets. If the gap is created by planets and gas is still present in it, then there should be a flow of gas past the planet into the inner region. It is our goal to study the mass accretion rate into the gap and in particular the dependency on the planet's mass and the thermodynamic properties of the disk. We performed 2D hydro simulations for disks with embedded planets. We added radiative cooling from the disk surfaces, radiative diffusion in the disk midplane, and stellar irradiation to the energy equation to have more realistic models. The mass flow rate into the gap region depends, for given disk thermodynamics, non-monotonically on the mass of the planet. Generally, more massive planets open wider and deeper gaps which ...

Mller, Tobias W A

2013-01-01T23:59:59.000Z

50

Model Year 1999 Fuel Economy Guide  

NLE Websites -- All DOE Office Websites (Extended Search)

FUEL FUEL ECONOMY GUIDE MODEL YEAR 1999 DOE/EE-0178 Fuel Economy Estimates October 1998 1 CONTENTS PAGE Purpose of the Guide ..................................................... 1 Interior Volume ................................................................ 1 How the Fuel Economy Estimates are Obtained ........... 1 Factors Affecting MPG .................................................... 2 Fuel Economy and Climate Change ............................... 2 Gas Guzzler Tax ............................................................. 2 Vehicle Classes Used in This Guide. .............................. 2 Annuel Fuel Costs .......................................................... 3 How to Use the Guide .................................................... 4 Where to Re-order Guides

51

Alternative fuels and vehicles choice model  

DOE Green Energy (OSTI)

This report describes the theory and implementation of a model of alternative fuel and vehicle choice (AFVC), designed for use with the US Department of Energy`s Alternative Fuels Trade Model (AFTM). The AFTM is a static equilibrium model of the world supply and demand for liquid fuels, encompassing resource production, conversion processes, transportation, and consumption. The AFTM also includes fuel-switching behavior by incorporating multinomial logit-type equations for choice of alternative fuel vehicles and alternative fuels. This allows the model to solve for market shares of vehicles and fuels, as well as for fuel prices and quantities. The AFVC model includes fuel-flexible, bi-fuel, and dedicated fuel vehicles. For multi-fuel vehicles, the choice of fuel is subsumed within the vehicle choice framework, resulting in a nested multinomial logit design. The nesting is shown to be required by the different price elasticities of fuel and vehicle choice. A unique feature of the AFVC is that its parameters are derived directly from the characteristics of alternative fuels and vehicle technologies, together with a few key assumptions about consumer behavior. This not only establishes a direct link between assumptions and model predictions, but facilitates sensitivity testing, as well. The implementation of the AFVC model as a spreadsheet is also described.

Greene, D.L. [Oak Ridge National Lab., TN (United States). Center for Transportation Analysis

1994-10-01T23:59:59.000Z

52

Towards Integrated Verification of Timed Transition Models  

Science Conference Proceedings (OSTI)

This paper describes an attempt to combine theorem proving and model-checking to formally verify real-time systems in a discrete time setting. The Timed Automata Modeling Environment (TAME) has been modified to provide a formal model for Time Transition ... Keywords: PVS, Real-time, SAL, equivalence verification, model reduction, model-checking, theorem proving

Mark Lawford; Vera Pantelic; Hong Zhang

2006-04-01T23:59:59.000Z

53

Chemical Kinetic Modeling of Advanced Transportation Fuels  

DOE Green Energy (OSTI)

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.

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

2009-01-20T23:59:59.000Z

54

HyPro: Modeling the Hydrogen Transition  

NLE Websites -- All DOE Office Websites (Extended Search)

and exercise it to determine the key drivers of the hydrogen transition. 2005 Develop a production database from H2A and an economic cost model to determine and compare...

55

Vehicle Modeling and Verification of CNG-Powered Transit Buses  

E-Print Network (OSTI)

Modeling and Verification of CNG-Powered Transit BusesModeling and Verification of CNG-Powered Transit Buses.Modeling and Veri?cation of CNG-Powered Transit Buses J.K.

Hedrick, J. K.; Ni, A.

2004-01-01T23:59:59.000Z

56

Metallic Fuel: Modeling and Simulation  

Science Conference Proceedings (OSTI)

Oct 9, 2012 ... Thermophyical Properties of Thoria and ThO2-UO2 Mixed Oxide Fuels ... Thorium-based nuclear fuel cycles are promising for their intrinsic...

57

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

E-Print Network (OSTI)

extra-heavy oil and shale have zero Resource- Cost), whileof the Oil Transition: Modeling Capacity, Costs, andof the oil transition: modeling capacity, costs, and

Brandt, Adam R.; Farrell, Alexander E.

2008-01-01T23:59:59.000Z

58

Methanol fuel cell model: Anode  

Science Conference Proceedings (OSTI)

An isothermal, steady-state model of an anode in a direct methanol feed, polymer electrolyte fuel cell is presented. The anode is considered to be a porous electrode consisting of an electronically conducting catalyst structure that is thinly coated with an ion-selective polymer electrolyte. The pores are filled with a feed solution of 2 M methanol in water. Four species are transported in the anode: water, methanol, hydrogen ions, and carbon dioxide. All four species are allowed to transport in the x-direction through the depth of the electrode. Species movement in the pseudo y-direction is taken into account for water, methanol, and carbon dioxide by use of an effective mass-transfer coefficient. Butler-Volmer kinetics are observed for the methanol oxidation reaction. Predictions of the model have been fitted with kinetic parameters from experimental data, and a sensitivity analysis was performed to identify critical parameters affecting the anode`s performance. Kinetic limitations are a dominant factor in the performance of the system. At higher currents, the polymer electrolyte`s conductivity and the anode`s thickness were also found to be important parameters to the prediction of a polymer electrolyte membrane fuel cell anode`s behavior in the methanol oxidation region 0.5--0.6 V vs. a reversible hydrogen electrode.

Baxter, S.F. [Argonne National Lab., IL (United States); Battaglia, V.S.; White, R.E. [Univ. of South Carolina, Columbia, SC (United States). Dept. of Chemical Engineering

1999-02-01T23:59:59.000Z

59

Fuel Cell Technologies Office: DOE Hydrogen Transition Analysis...  

NLE Websites -- All DOE Office Websites (Extended Search)

Energy Efficiency and Renewable Energy EERE Home | Programs & Offices | Consumer Information Fuel Cell Technologies Office Search Search Help Fuel Cell Technologies Office HOME...

60

Alternative fuel transit buses: Interim results from the National Renewable Energy Laboratory (NREL) Vehicle Evaluation Program  

DOE Green Energy (OSTI)

The transit bus program is designed to provide a comprehensive study of the alternative fuels currently used by the transit bus industry. The study focuses on the reliability, fuel economy, operating costs, and emissions of vehicles running on the various fuels and alternative fuel engines. The alternative fuels being tested are methanol, ethanol, biodiesel and natural gas. The alternative fuel buses in this program use the most common alternative fuel engines from the heavy-duty engine manufacturers. Data are collected in four categories: Bus and route descriptions; Bus operating data; Emissions data; and, Capital costs. The goal is to collect 18 months of data on each test bus. This report summarizes the interim results from the project to date. The report addresses performance and reliability, fuel economy, costs, and emissions of the busses in the program.

Motta, R.; Norton, P.; Kelly, K.J.; Chandler, K.

1995-05-01T23:59:59.000Z

Note: This page contains sample records for the topic "fuels modeling transition" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


61

Used Fuel Degradation: Experimental and Modeling Report  

Energy.gov (U.S. Department of Energy (DOE))

The report describes the strategy for coupling process level models to produce an integrated Used Fuel Degradation Model (FDM), and addresses fractional degradation rate, instant release fractions, other continuum modeling approaches, and experimental support.

62

Autopia: A Game on Long Term Vehicle and Fuel Transitions  

E-Print Network (OSTI)

groups with a single budget for vehicle and fuel. Consumers have two goals: firstly, to keep their cars for electricity from PHEVs and BEVs. Sample fuel data charts. #12;Autopia Status and Goals Autopia is a policy

California at Davis, University of

63

Enthalpy of gamma-delta Transition in Ternary U-Pu-Zr Fuel Alloys  

Science Conference Proceedings (OSTI)

Presentation Title, Enthalpy of gamma-delta Transition in Ternary U-Pu-Zr Fuel ... that the activities of Pu and Zr in the delta phase may be self-compensating.

64

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

NLE Websites -- All DOE Office Websites (Extended Search)

Fuel Cell Buses in U.S. Transit Fuel Cell Buses in U.S. Transit Fleets: Current Status 2012 Leslie Eudy National Renewable Energy Laboratory Kevin Chandler Battelle Christina Gikakis Federal Transit Administration Technical Report NREL/TP-5600-56406 November 2012 NREL is a national laboratory of the U.S. Department of Energy, Office of Energy Efficiency & Renewable Energy, operated by the Alliance for Sustainable Energy, LLC. National Renewable Energy Laboratory 15013 Denver West Parkway Golden, Colorado 80401 303-275-3000 * www.nrel.gov Contract No. DE-AC36-08GO28308 Fuel Cell Buses in U.S. Transit Fleets: Current Status 2012 Leslie Eudy National Renewable Energy Laboratory Kevin Chandler Battelle Christina Gikakis Federal Transit Administration

65

Liquid Fuels Market Model (LFMM) Unveiling LFMM  

Gasoline and Diesel Fuel Update (EIA)

Implementation of the Renewable Fuel Implementation of the Renewable Fuel Standard (RFS) in the Liquid Fuels Market Module (LFMM) of NEMS Michael H. Cole, PhD, PE michael.cole@eia.gov August 1, 2012 | Washington, DC LFMM / NEMS overview 2 M. Cole, EIA Advanced Biofuels Workshop August 1, 2012 | Washington, DC * LFMM is a mathematical representation of the U.S. liquid fuels market (motor gasoline, diesel, biofuels, etc.). EIA analysts use LFMM to project motor fuel prices and production approaches through 2040. * LFMM is a cost-minimization linear program (LP). For a given set of fuel demands, LFMM will find the least-cost means of satisfying those demands, subject to various constraints (such as the RFS). * LFMM is part of the National Energy Modeling System (NEMS), which is a computer model of the U.S. energy economy. EIA uses

66

GENERATION OF TRANSITION CLASS MODELS FROM FORMAL QUEUEING NETWORK DESCRIPTIONS  

E-Print Network (OSTI)

for service. The state is changed accordingly. The service rate, the number of queues, and transition probabil probabilities and the transition rates or the transition probabilities (Markov reward mod- els). The holding is a translator into transition class models. The expressive power of the method is indicated. TRANSITION CLASSES

Strelen, Christoph

67

Bay Area Transit Agencies Propel Fuel Cell Buses Toward Commercialization (Fact Sheet)  

Science Conference Proceedings (OSTI)

This fact sheet describes the Zero Emission Bay Area (ZEBA) demonstration of the next generation of fuel cells buses. Several transit agencies in the San Francisco Bay Area are participating in demonstrating the largest single fleet of fuel cell buses in the United States.

Not Available

2010-07-01T23:59:59.000Z

68

Exploring technology evolution and transition characteristics of leading countries: A case of fuel cell field  

Science Conference Proceedings (OSTI)

In the course of the technology evolution, the status of leading countries changes with the times. Leading countries may persist, appear, or disappear, i.e. the change of which is named ''transitions'' which may be effected by some characteristics. An ... Keywords: Fuel cell technology, Leading countries, Patent analysis, Technology evolution, Transition patterns

Ssu-Han Chen, Mu-Hsuan Huang, Dar-Zen Chen

2013-08-01T23:59:59.000Z

69

Infrastructure Analysis of Early Market Transition of Fuel Cell...  

NLE Websites -- All DOE Office Websites (Extended Search)

1 FY 2012 Annual Progress Report DOE Hydrogen and Fuel Cells Program Brian Bush (Primary Contact), Marc Melaina, Olga Sozinova, Michael Penev National Renewable Energy Laboratory...

70

Timing is everything : along the fossil fuel transition pathway.  

Science Conference Proceedings (OSTI)

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.

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

2013-10-01T23:59:59.000Z

71

Timing is everything : along the fossil fuel transition pathway.  

SciTech Connect

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.

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

2013-10-01T23:59:59.000Z

72

Integrated Market Modeling of Hydrogen Transition Scenarios with HyTrans  

NLE Websites -- All DOE Office Websites (Extended Search)

Integrated Market Modeling of Integrated Market Modeling of Hydrogen Transition Scenarios with HyTrans Paul N. Leiby, David L. Greene and David Bowman Oak Ridge National Laboratory A presentation to the Hydrogen Delivery Analysis Meeting FreedomCAR and Fuels Partnership Delivery, Storage and Hydrogen Pathways Tech Teams May 8-9, 2007 Columbia, MD 2 OAK RIDGE NATIONAL LABORATORY U. S. DEPARTMENT OF ENERGY Drawing from several other DOE models, HyTrans integrates supply and demand in a dynamic non-linear market model to 2050. * H2A - Hydrogen Production - Hydrogen Delivery * PSAT & ASCM - Fuel economy - 2010/2015 cost & performance goals * ORNL Vehicle Choice Model - Fuel availability - Make & model diversity - Price, fuel economy, etc. * Vehicle Manufacturing Cost Estimates (assisted by OEMs)

73

VISION: Verifiable Fuel Cycle Simulation Model  

SciTech Connect

The nuclear fuel cycle consists of a set of complex components that work together in unison. In order to support the nuclear renaissance, it is necessary to understand the impacts of changes and timing of events in any part of the fuel cycle system. The Advanced Fuel Cycle Initiatives systems analysis group is developing a dynamic simulation model, VISION, to capture the relationships, timing, and changes in and among the fuel cycle components to help develop an understanding of how the overall fuel cycle works. This paper is an overview of the philosophy and development strategy behind VISION. The paper includes some descriptions of the model components and some examples of how to use VISION.

Jacob Jacobson; A. M. Yacout; Gretchen Matthern; Steven Piet; David Shropshire; Tyler Schweitzer

2010-11-01T23:59:59.000Z

74

Cryogenic Fuel Tank Draining Analysis Model  

E-Print Network (OSTI)

One of the technological challenges in designing advanced hypersonic aircraft and the next generation of spacecraft is developing reusable flight-weight cryogenic fuel tanks. As an aid in the design and analysis of these cryogenic tanks, a computational fluid dynamics (CFD) model has been developed specifically for the analysis of flow in a cryogenic fuel tank. This model employs the full set of Navier-Stokes equations, except that viscous dissipation is neglected in the energy equation. An explicit finite difference technique in two-dimensional generalized coordinates, approximated to second-order accuracy in both space and time is used. The stiffness resulting from the low Mach number is resolved by using artificial compressibility. The model simulates the transient, two-dimensional draining of a fuel tank cross section. To calculate the slosh wave dynamics the interface between the ullage gas and liquid fuel is modeled as a free surface. Then, experimental data for free convection i...

Donald Greer Research; Donald Greer

1999-01-01T23:59:59.000Z

75

Modeling of solid oxide fuel cells  

E-Print Network (OSTI)

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 ...

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

2006-01-01T23:59:59.000Z

76

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

DOE Green Energy (OSTI)

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.

Eudy, L.; Chandler, K.

2013-01-01T23:59:59.000Z

77

Fuel Conditioning Facility Electrorefiner Process Model  

SciTech Connect

The Fuel Conditioning Facility at the Idaho National Laboratory processes spent nuclear fuel from the Experimental Breeder Reactor II using electro-metallurgical treatment. To process fuel without waiting for periodic sample analyses to assess process conditions, an electrorefiner process model predicts the composition of the electrorefiner inventory and effluent streams. For the chemical equilibrium portion of the model, the two common methods for solving chemical equilibrium problems, stoichiometric and non stoichiometric, were investigated. In conclusion, the stoichiometric method produced equilibrium compositions close to the measured results whereas the non stoichiometric method did not.

DeeEarl Vaden

2005-10-01T23:59:59.000Z

78

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

DOE Green Energy (OSTI)

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.

Eudy, L.; Chandler, K.

2011-03-01T23:59:59.000Z

79

Fuel Economy of the 2013 Ford Transit Connect Wagon FWD  

NLE Websites -- All DOE Office Websites (Extended Search)

of This Page 4 cyl, 2.0 L Automatic 4-spd Regular Gasoline Compare Side-by-Side EPA Fuel Economy Miles per Gallon Personalize Regular Gasoline 24 Combined 22 City 27 Highway...

80

Fuel Cell Technologies Office: Transport Modeling Working Group  

NLE Websites -- All DOE Office Websites (Extended Search)

Transport Modeling Transport Modeling Working Group to someone by E-mail Share Fuel Cell Technologies Office: Transport Modeling Working Group on Facebook Tweet about Fuel Cell Technologies Office: Transport Modeling Working Group on Twitter Bookmark Fuel Cell Technologies Office: Transport Modeling Working Group on Google Bookmark Fuel Cell Technologies Office: Transport Modeling Working Group on Delicious Rank Fuel Cell Technologies Office: Transport Modeling Working Group on Digg Find More places to share Fuel Cell Technologies Office: Transport Modeling Working Group on AddThis.com... Key Activities Plans, Implementation, & Results Accomplishments Organization Chart & Contacts Quick Links Hydrogen Production Hydrogen Delivery Hydrogen Storage Fuel Cells Technology Validation

Note: This page contains sample records for the topic "fuels modeling transition" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


81

Computational Fuel Cell Research and SOFC Modeling at Penn State  

E-Print Network (OSTI)

Computational Fuel Cell Research and SOFC Modeling at Penn State Chao-Yang Wang Professor of PEM Fuel Cells SOFC Modeling & Simulation Fuel Cell Controls Summary #12;ECEC Overview Vision: provide, DMFC, and SOFC #12;ECEC Facilities (>5,000 sq ft) Fuel Cell/Battery Experimental Labs Fuel Cell

82

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

Reports and Publications (EIA)

On November 8, 2005, the EPA Administrator signed a direct final rule that will shift the retail compliance date for offering 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.

Information Center

2006-02-01T23:59:59.000Z

83

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

DOE Green Energy (OSTI)

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.

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

2012-11-01T23:59:59.000Z

84

Abrupt Transitions and Hysteresis in Thermohaline Laboratory Models  

Science Conference Proceedings (OSTI)

As a driving parameter is slowly altered, thermohaline ocean circulation models show either a smooth evolution of a mode of flow or an abrupt transition of temperature and salinity fields from one mode to another. An abrupt transition might occur ...

J. A. Whitehead

2009-05-01T23:59:59.000Z

85

A Stochastic Model for the Transition to Strong Convection  

Science Conference Proceedings (OSTI)

A simple stochastic model is designed and analyzed in order to further understand the transition to strong convection. The transition has been characterized recently in observational data by an array of statistical measures, including (i) a sharp ...

Samuel N. Stechmann; J. David Neelin

2011-12-01T23:59:59.000Z

86

Mathematical modeling of solid oxide fuel cells using hydrocarbon fuels  

E-Print Network (OSTI)

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 ...

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

2012-01-01T23:59:59.000Z

87

Fuel Cell Power (FCPower) Model | Open Energy Information  

Open Energy Info (EERE)

Fuel Cell Power (FCPower) Model Fuel Cell Power (FCPower) Model Jump to: navigation, search Tool Summary Name: Fuel Cell Power (FCPower) Model Agency/Company /Organization: United States Department of Energy Partner: National Renewable Energy Laboratory Sector: Energy Focus Area: Hydrogen Topics: Finance Resource Type: Software/modeling tools User Interface: Spreadsheet Website: www.hydrogen.energy.gov/fc_power_analysis.html Cost: Free OpenEI Keyword(s): EERE tool Fuel Cell Power (FCPower) Model Screenshot References: DOE Fuel Cell Power Analysis[1] Logo: Fuel Cell Power (FCPower) Model The Fuel Cell Power (FCPower) Model is a financial tool for analyzing high-temperature, fuel cell-based tri-generation systems. "The Fuel Cell Power (FCPower) Model is a financial tool for analyzing

88

Progress in Chemical Kinetic Modeling for Surrogate Fuels  

DOE Green Energy (OSTI)

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.

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

2008-06-06T23:59:59.000Z

89

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

NLE Websites -- All DOE Office Websites (Extended Search)

SunLine Transit Agency SunLine Transit Agency Advanced Technology Fuel Cell Bus Evaluation: Fourth Results Report L. Eudy and K. Chandler Technical Report NREL/TP-5600-57560 January 2013 NREL is a national laboratory of the U.S. Department of Energy, Office of Energy Efficiency & Renewable Energy, operated by the Alliance for Sustainable Energy, LLC. National Renewable Energy Laboratory 15013 Denver West Parkway Golden, Colorado 80401 303-275-3000 * www.nrel.gov Contract No. DE-AC36-08GO28308 SunLine Transit Agency Advanced Technology Fuel Cell Bus Evaluation: Fourth Results Report L. Eudy and K. Chandler Prepared under Task No. HT12.8210 Technical Report NREL/TP-5600-57560 January 2013 NOTICE This report was prepared as an account of work sponsored by an agency of the United States government.

90

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...

91

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...

92

CNG transit fueling station handbook. Final report, October 1993-June 1997  

Science Conference Proceedings (OSTI)

This manual has been complied for use by a Transit Authority Engineer or an Engineering Company who is involved in the design of Compressed Natural Gas (CNG) fueling facilities. It is intended to provide a convenient and comprehensive reference document, to supplement but not replace codes and other reference documents. It is also intended to be used as a basis for the design of a broad range of CNG fueling facilities. The scope is limited to straight CNG and hence Liquefied Natural Gas (LNG) or LNG vaporization to CNG has not been addressed. Similarly, this document does not deal with the facility modifications which may be required to park, service, or fuel CNG buses indoors. Additional information on actual gas fueling is available from the Gas Research Institute.

Adams, R.R.; Pennington, M.D.

1997-02-01T23:59:59.000Z

93

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

DOE Green Energy (OSTI)

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.

Eudy, L.; Chandler, K.

2012-05-01T23:59:59.000Z

94

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

Science Conference Proceedings (OSTI)

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.

Eudy, L.; Chandler, K.

2011-10-01T23:59:59.000Z

95

Fuel Cell Vehicle World Survey 2003-Fuel Cells in Transit Buses  

NLE Websites -- All DOE Office Websites (Extended Search)

range of heavy-duty diesel, compressed natural gas (CNG), and liquefied natural gas (LNG) transit buses. NABI, Inc., is a wholly owned subsidiary of NABI Rt., which was...

96

AN EVALUATION OF SELECT PEM FUEL CELL SYSTEM MODELS  

NLE Websites -- All DOE Office Websites (Extended Search)

EVALUATING PEM FUEL CELL SYSTEM MODELS EVALUATING PEM FUEL CELL SYSTEM MODELS Kristina Haraldsson, Keith Wipke National Renewable Energy Laboratory (NREL) 1617 Cole Boulevard, MS 1633 Golden, Colorado, 80401 ABSTRACT Many proton exchange membrane (PEM) fuel cell models have been reported in publications, and some are available commercially. This paper helps users match their modeling needs with specific fuel cell models. The paper has three parts. First, it describes the model selection criteria for choosing a fuel cell model. Second, it applies these criteria to select state- of-the-art fuel cell models available in literature and commercially. The advantages and disadvantages of commercial models are discussed. Third, the paper illustrates the process of choosing a fuel cell model with an

97

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

E-Print Network (OSTI)

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 ...

Soontrapa, Chaiyod

2005-01-01T23:59:59.000Z

98

Agent-Based Modeling and Simulation for Hydrogen Transition Analysis  

NLE Websites -- All DOE Office Websites (Extended Search)

Agent Agent Agent - - Based Modeling Based Modeling and Simulation (ABMS) and Simulation (ABMS) for Hydrogen Transition for Hydrogen Transition Analysis Analysis Marianne Mintz Hydrogen Transition Analysis Workshop US Department of Energy January 26, 2006 Objectives and Scope for Phase 1 2 Analyze the hydrogen infrastructure development as a complex adaptive system using an agent-based modeling and simulation (ABMS) approach Develop an ABMS model to simulate the evolution of that system, spanning the entire H2 supply chain from production to consumption Identify key factors that either promote or inhibit the growth of H2 infrastructure Apply ABMS to get new insights into transition, particularly early transition phase - Dynamic interplay between supply and demand

99

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

DOE Green Energy (OSTI)

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.

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

1996-03-20T23:59:59.000Z

100

Modeling Deep Burn TRISO Particle Nuclear Fuel  

Science Conference Proceedings (OSTI)

Under the DOE Deep Burn program TRISO fuel is being investigated as a fuel form for consuming plutonium and minor actinides, and for greater efficiency in uranium utilization. The result will thus be to drive TRISO particulate fuel to very high burn-ups. In the current effort the various phenomena in the TRISO particle are being modeled using a variety of techniques. The chemical behavior is being treated utilizing thermochemical analysis to identify phase formation/transformation and chemical activities in the particle, including kernel migration. First principles calculations are being used to investigate the critical issue of fission product palladium attack on the SiC coating layer. Density functional theory is being used to understand fission product diffusion within the plutonia oxide kernel. Kinetic Monte Carlo techniques are shedding light on transport of fission products, most notably silver, through the carbon and SiC coating layers. The diffusion of fission products through an alternative coating layer, ZrC, is being assessed via DFT methods. Finally, a multiscale approach is being used to understand thermal transport, including the effect of radiation damage induced defects, in a model SiC material.

Besmann, Theodore M [ORNL; Stoller, Roger E [ORNL; Samolyuk, German D [ORNL; Schuck, Paul C [ORNL; Rudin, Sven [Los Alamos National Laboratory (LANL); Wills, John [Los Alamos National Laboratory (LANL); Wirth, Brian D. [University of California, Berkeley; Kim, Sungtae [University of Wisconsin, Madison; Morgan, Dane [University of Wisconsin, Madison; Szlufarska, Izabela [University of Wisconsin, Madison

2012-01-01T23:59:59.000Z

Note: This page contains sample records for the topic "fuels modeling transition" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


101

Utility Fuel Inventory Model (UFIM) 5.0  

Science Conference Proceedings (OSTI)

The Utility Fuel Inventory Model (UFIM) is the essential tool for performing fuel inventory analysis. Using the power of your personal computer, UFIM helps users develop money-saving inventory ...

2012-11-06T23:59:59.000Z

102

Modeling Nuclear Fuels with a Combined Potts-Phase Field Model  

Science Conference Proceedings (OSTI)

Symposium, Materials Science Challenges for Nuclear Applications. Presentation Title, Modeling Nuclear Fuels with a Combined Potts-Phase Field Model.

103

DOE Hydrogen Analysis Repository: Hydrogen Fueling Station Economics Model  

NLE Websites -- All DOE Office Websites (Extended Search)

Fueling Station Economics Model Fueling Station Economics Model Project Summary Full Title: Hydrogen Fueling Station Economics Model Project ID: 193 Principal Investigator: Bill Liss Brief Description: The Gas Technology Institute developed a hydrogen fueling station economics model as part of their project to develop a natural gas to hydrogen fuel station. Keywords: Compressed gas; vehicle; refueling station; cost; natural gas Purpose Calculate hydrogen fueling station costs, including capital, operating, and maintenance costs. Performer Principal Investigator: Bill Liss Organization: Gas Technology Institute Address: 1700 South Mount Prospect Road Des Plains, IL 60018-1804 Telephone: 847-768-0530 Email: william.liss@gastechnology.org Project Description Type of Project: Model Category: Hydrogen Fuel Pathways

104

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

DOE Patents (OSTI)

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).

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

2012-01-17T23:59:59.000Z

105

Transit-Time Distributions in a Global Ocean Model  

Science Conference Proceedings (OSTI)

Results from a simulation of the ocean transit-time distribution (TTD) for global and regional ocean surface boundary conditions are presented based on a 5000-yr integration using the Parallel Ocean Program ocean general circulation model. ...

Synte Peacock; Mathew Maltrud

2006-03-01T23:59:59.000Z

106

Gaseous Fuel Injection Modeling using a Gaseous Sphere Injection Methodology  

DOE Green Energy (OSTI)

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

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

2006-03-06T23:59:59.000Z

107

Dynamic Modeling in Solid-Oxide Fuel Cells Controller Design  

SciTech Connect

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.

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

2007-06-28T23:59:59.000Z

108

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

DOE Green Energy (OSTI)

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.

Leiby, P.N.

1993-09-01T23:59:59.000Z

109

Fuel Inventory Management for Electric Companies: Current Uses of the EPRI Utility Fuel Inventory Model (UFIM)  

Science Conference Proceedings (OSTI)

This report describes current applications of the Utility Fuel Inventory Model (UFIM) developed by the Electric Power Research Institute (EPRI). This model is designed to help electric companies to better manage policy and operational decisions related to managing power plant fuel inventories. This report specifically address: (i) problems currently faced by electric power companies where fuel inventories can be used to address the problems; and, (ii) how the UFIM analysis tool can be used to ...

2013-07-26T23:59:59.000Z

110

Combustion Characterization and Modelling of Fuel Blends for...  

NLE Websites -- All DOE Office Websites (Extended Search)

Value (405,990 DOE) COMBUSTION CHARACTERIZATION AND MODELLING OF FUEL BLENDS FOR POWER GENERATION GAS TURBINES University of Central Florida Presentation-Petersen, 1013...

111

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

NLE Websites -- All DOE Office Websites (Extended Search)

against * steady state and transient operational cell data. Complete fuel cell water transport model improvements * and code package development to include two phase flow....

112

VISION Model for Vehicle Technologies and Alternative Fuels | Open Energy  

Open Energy Info (EERE)

VISION Model for Vehicle Technologies and Alternative Fuels VISION Model for Vehicle Technologies and Alternative Fuels Jump to: navigation, search Tool Summary LAUNCH TOOL Name: VISION Model for Vehicle Technologies and Alternative Fuels Agency/Company /Organization: Argonne National Laboratory Sector: Energy Focus Area: Transportation Phase: Create a Vision Resource Type: Software/modeling tools User Interface: Desktop Application Website: www.transportation.anl.gov/modeling_simulation/VISION/ OpenEI Keyword(s): EERE tool, VISION Model for Vehicle Technologies and Alternative Fuels References: The VISION Model [1] Estimate the potential energy use, oil use, and carbon emission impacts of advanced light and heavy-duty vehicle technologies and alternative fuels through 2050. The VISION model has been developed to provide estimates of the potential

113

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

E-Print Network (OSTI)

W gasoline SOFC technology development program APU applications can provide entry markets for fuel cell & Select APU Systems 2 · Summarize PEM and SOFC performance parameters · Determine most promising future Task 3: Develop design concepts · Truck Cab/SOFC/diesel · Transit bus/SOFC/CNG or diesel · Police

114

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

E-Print Network (OSTI)

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

Zhao, Hengbing; Burke, Andy

2008-01-01T23:59:59.000Z

115

DOE Hydrogen Analysis Repository: Hydrogen Transition Model ...  

NLE Websites -- All DOE Office Websites (Extended Search)

Report ArticleAbstract Title: VII.11 Development of HyTrans Model and Integrated Scenario Analysis Page number(s): 1307 Publisher: U.S. Department of Energy Author...

116

Software Requirements Specification Verifiable Fuel Cycle Simulation (VISION) Model  

SciTech Connect

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.

D. E. Shropshire; W. H. West

2005-11-01T23:59:59.000Z

117

Variable fuel tax models. [Revenue generated via 4 models for Alabama  

SciTech Connect

Four variable fuel tax models are investigated with respect to Alabama Highway Department operations. The Fixed Percentage Fuel Tax Model establishes the state gasoline tax as a constant percentage of the wholesale price of gasoline. The Price Index Economic Model pegs state fuel taxes to a ratio of price indexes. The Fuel Efficiency Tax Model relates the gasoline tax to the variables of Consumer Price Index and vehicle efficiency. The Sales Tax Model establishes a sales tax on the purchase of gasoline and motor fuel sold in the state. Estimates of the amount of revenue expected to be generated by each model are made. Advantages and disadvantages of each model are presented.

Vecellio, R.L.; Moore, R.K.

1977-07-01T23:59:59.000Z

118

Mechanical modeling of porous oxide fuel pellet A Test Problem  

Science Conference Proceedings (OSTI)

A poro-elasto-plastic material model has been developed to capture the response of oxide fuels inside the nuclear reactors under operating conditions. Behavior of the oxide fuel and variation in void volume fraction under mechanical loading as predicted by the developed model has been reported in this article. The significant effect of void volume fraction on the overall stress distribution of the fuel pellet has also been described. An important oxide fuel issue that can have significant impact on the fuel performance is the mechanical response of oxide fuel pellet and clad system. Specifically, modeling the thermo-mechanical response of the fuel pellet in terms of its thermal expansion, mechanical deformation, swelling due to void formation and evolution, and the eventual contact of the fuel with the clad is of significant interest in understanding the fuel-clad mechanical interaction (FCMI). These phenomena are nonlinear and coupled since reduction in the fuel-clad gap affects thermal conductivity of the gap, which in turn affects temperature distribution within the fuel and the material properties of the fuel. Consequently, in order to accurately capture fuel-clad gap closure, we need to account for fuel swelling due to generation, retention, and evolution of fission gas in addition to the usual thermal expansion and mechanical deformation. Both fuel chemistry and microstructure also have a significant effect on the nucleation and growth of fission gas bubbles. Fuel-clad gap closure leading to eventual contact of the fuel with the clad introduces significant stresses in the clad, which makes thermo-mechanical response of the clad even more relevant. The overall aim of this test problem is to incorporate the above features in order to accurately capture fuel-clad mechanical interaction. Because of the complex nature of the problem, a series of test problems with increasing multi-physics coupling features, modeling accuracy, and complexity are defined with the objective of accurate simulation of fuel-clad mechanical interaction subjected to a wide-range of thermomechanical stimuli.

Nukala, Phani K [ORNL; Barai, Pallab [ORNL; Simunovic, Srdjan [ORNL; Ott, Larry J [ORNL

2009-10-01T23:59:59.000Z

119

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

E-Print Network (OSTI)

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-

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

2010-01-01T23:59:59.000Z

120

Alternative Fuels Data Center: Heavy-Duty Vehicle and Engine...  

Alternative Fuels and Advanced Vehicles Data Center (EERE)

Van Hool - A300L Fuel Cel Application: Bus - Transit Fuel Type: Hydrogen Maximum Seating: 28 Power Source(s): UTC Power - PureMotion Model 120 Fuel Cell System...

Note: This page contains sample records for the topic "fuels modeling transition" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


121

Boiler Water Deposition Model for Fossil-Fueled Power Plants  

Science Conference Proceedings (OSTI)

The feasibility and initial development of an integrated, deterministic model of the various processes governing deposition in fossil boilers was assessed in the Electric Power Research Institute (EPRI) reports Boiler Water Deposition Model for Fossil Fuel Plants, Part 1: Feasibility Study (1004931), published in 2004; Boiler Water Deposition Model for Fossil Fuel Plants, Part 2: Initial Deterministic Model Development and Deposit Characterization (1012207) published in 2007; and Boiler Water Deposition ...

2009-03-12T23:59:59.000Z

122

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

NLE Websites -- All DOE Office Websites (Extended Search)

Used for Off-Road Recreation: Used for Off-Road Recreation: A Reassessment of the Fuel Use Model Stacy C. Davis Lorena F. Truett Patricia S. Hu ORNL/TM-1999/100 Fuel Used for Off-Road Recreation: A Reassessment of the Fuel Use Model Stacy C. Davis Lorena F. Truett Patricia S. Hu July 1999 Prepared for the Office of Highway Information Management Federal Highway Administration U.S. Department of Transportation Washington, DC 20590 Prepared by the Statistics and Data Analysis Program Center for Transportation Analysis Oak Ridge National Laboratory Oak Ridge, TN 37831-6073 managed by Lockheed Martin Energy Research Corporation for the U.S. Department of Energy under Contract No. DE-AC05-96OR22464 Fuel Used for Off-Road Recreation: A Reassessment of the Fuel Use Model - iii - TABLE OF CONTENTS LIST OF ACRONYMS AND ABBREVIATIONS

123

Fuel Cell Systems Sensors Air Management Benchmarking Modeling  

NLE Websites -- All DOE Office Websites (Extended Search)

Systems Systems F u e l P r o c e s s o r Sensors Air Management Benchmarking Modeling Patrick Davis Patrick Davis Targets and Status 50 kWe (net) Integrated Fuel Cell Power System 5000 2000 1000 Hours Durability 45 125 275 $/kW Cost (including H2 storage) 650 500 400 W/L Power density (w/o H2 stor) Operating on direct hydrogen 5000 2000 1000 Hours Durability 45 125 325 $/kW Cost 325 250 140 W/L Power density Operating on Tier 2 gasoline containing 30 ppm sulfur, average 2010 2005 2003 status Units Characteristics Projects Fuel Cell Power Systems Analysis ANL NREL TIAX Directed Technologies, Inc. TIAX TIAX * Fuel Cell Systems Analysis * Fuel Cell Vehicle Systems Analysis * Cost Analyses of Fuel Cell Stacks/ Systems * DFMA Cost Estimates of Fuel Cell/ Reformer Systems at Low, Medium, & High Production Rates * Assessment of Fuel Cell Auxiliary

124

Liquid Fuels Market Model of the National Energy Modeling ...  

U.S. Energy Information Administration (EIA)

The outside battery-limit (OSBL) costs include the cost of cooling water, steam and electric power generation and distribution, fuel oil and fuel gas ...

125

Surrogate Model Development for Fuels for Advanced Combustion Engines  

Science Conference Proceedings (OSTI)

The fuels used in internal-combustion engines are complex mixtures of a multitude of different types of hydrocarbon species. Attempting numerical simulations of combustion of real fuels with all of the hydrocarbon species included is highly unrealistic. Thus, a surrogate model approach is generally adopted, which involves choosing a few representative hydrocarbon species whose overall behavior mimics the characteristics of the target fuel. The present study proposes surrogate models for the nine fuels for advanced combustion engines (FACE) that have been developed for studying low-emission, high-efficiency advanced diesel engine concepts. The surrogate compositions for the fuels are arrived at by simulating their distillation profiles to within a maximum absolute error of 4% using a discrete multi-component (DMC) fuel model that has been incorporated in the multi-dimensional computational fluid dynamics (CFD) code, KIVA-ERC-CHEMKIN. The simulated surrogate compositions cover the range and measured concentrations of the various hydrocarbon classes present in the fuels. The fidelity of the surrogate fuel models is judged on the basis of matching their specific gravity, lower heating value, hydrogen/carbon (H/C) ratio, cetane number, and cetane index with the measured data for all nine FACE fuels.

Anand, Krishnasamy [University of Wisconsin, Madison; Ra, youngchul [University of Wisconsin, Madison; Reitz, Rolf [University of Wisconsin; Bunting, Bruce G [ORNL

2011-01-01T23:59:59.000Z

126

Fossil Fuel Emission Verification Modeling at LLNL  

SciTech Connect

We have an established project at LLNL to develop the tools needed to constrain fossil fuel carbon dioxide emissions using measurements of the carbon-14 isotope in atmospheric samples. In Figure 1 we show the fossil fuel plumes from Los Angeles and San Francisco for two different weather patterns. Obviously, a measurement made at any given location is going to depend on the weather leading up to the measurement. Thus, in order to determine the GHG emissions from some region using in situ measurements of those GHGs, we use state-of-the-art global and regional atmospheric chemistry-transport codes to simulate the plumes: the LLNL-IMPACT model (Rotman et al., 2004) and the WRFCHEM community code (http://www.wrf-model.org/index.php). Both codes can use observed (aka assimilated) meteorology in order to recreate the actual transport that occurred. The measured concentration of each tracer at a particular spatio-temporal location is a linear combination of the plumes from each region at that location (for non-reactive species). The challenge is to calculate the emission strengths for each region that fit the observed concentrations. In general this is difficult because there are errors in the measurements and modeling of the plumes. We solve this inversion problem using the strategy illustrated in Figure 2. The Bayesian Inference step combines the a priori estimates of the emissions, and their uncertainty, for each region with the results of the observations, and their uncertainty, and an ensemble of model predicted plumes for each region, and their uncertainty. The result is the mathematical best estimate of the emissions and their errors. In the case of non-linearities, or if we are using a statistical sampling technique such as a Markov Chain Monte Carlo technique, then the process is iterated until it converges (ie reaches stationarity). For the Bayesian inference we can use both a direct inversion capability, which is fast but requires assumptions of linearity and Gaussianity of errors, or one of several statistical sampling techniques, which are computationally slower but do not require either linearity or Gaussianity (Chow, et al., 2008; Delle Monache, et al., 2008). The emission regions we are using are based on the air-basins defined by the California Air Resources Board (CARB), see Figure 3. The only difference is that we have joined some of the smaller air basins together. The results of a test using 4 days of simulated observations using our ensemble retrieval system are shown in Figure 3 (right). The main source of the variation between the different model configurations arises from the uncertainty in the atmospheric boundary layer parameterization in the WRF model. We are currently developing a capability to constrain the boundary layer height in our carbon-14 work either by weighting the ensemble member results by the accuracy of their boundary layer height (using commercial aircraft observations), or as part of the retrieval process using an ensemble Kalman filter (EnKF) capability.

Cameron-Smith, P; Kosovic, B; Guilderson, T; Monache, L D; Bergmann, D

2009-08-06T23:59:59.000Z

127

Engineering models of deflagration-to-detonation transition  

Science Conference Proceedings (OSTI)

For the past two years, Los Alamos has supported research into the deflagration-to-detonation transition (DDT) in damaged energetic materials as part of the explosives safety program. This program supported both a theory/modeling group and an experimentation group. The goal of the theory/modeling group was to examine the various modeling structures (one-phase models, two-phase models, etc.) and select from these a structure suitable to model accidental initiation of detonation in damaged explosives. The experimental data on low-velocity piston supported DDT in granular explosive was to serve as a test bed to help in the selection process. Three theoretical models have been examined in the course of this study: (1) the Baer-Nunziato (BN) model, (2) the Stewart-Prasad-Asay (SPA) model and (3) the Bdzil-Kapila-Stewart model. Here we describe these models, discuss their properties, and compare their features.

Bdzil, J.B.; Son, S.F.

1995-07-01T23:59:59.000Z

128

Proceedings of the NETL Workshop on Fuel Cell Modeling  

SciTech Connect

This workshop was the first U.S. DOE sponsored meeting devoted to fuel cell modeling. The workshop was attended by over 45 people from industry, universities, and the government. The goals of the meeting were to assess the status of fuel cell modeling, and determine how new developments in fuel cell modeling can improve cell design, stack design, and power system design. The primary focus was on cell and stack modeling. Following a review of DOE/NETL fuel cell related programs and activities, Professor Robert Selman (Illinois Institute of Technology) kicked off the technical portion of the workshop by presenting an overview of fuel cell phenomena and the status of fuel cell modeling. This overview provided the necessary background for establishing a common framework for discussing fuel cell modeling. A distinction was made between micro modeling, electrode modeling, cell modeling, stack modeling, and system modeling. It was proposed that all modeling levels be supported for further development. In addition, due to significant advances being made outside the U.S., it was proposed that dialog/exchange with other international researchers be established. Following the Overview Session, eight leading researchers in modeling gave individual presentations. These presentations provided additional information on the status and present direction of model developments. All these presentations can be found in Attachment A. Before the workshop, a survey was sent out requesting comments from the attendees. Results from this survey can be found in Attachment B. This survey was then used as initial talking points at the individual breakout sessions on the afternoon of the workshop. Breakouts were organized by microfundamental modeling, cell modeling, stack modeling, and systems modeling.

Randall S. Gemmen; J. R. Selman

2000-04-18T23:59:59.000Z

129

Page 1 Session 7: Material Phase Transition, Modeling, and Other  

National Nuclear Security Administration (NNSA)

7: Material Phase Transition, Modeling, and Other 7: Material Phase Transition, Modeling, and Other Thermodynamically Consistent Method for Calculation of Free Energy and Equilibrium Curves of First-Order Phase Transitions in Classical Molecular Dynamics *A.V. Karavaev andV.V. Dremov Russian Federal Nuclear Centre - Zababakhin Institute of Technical Physics, Snezhinsk, Russia State-of-the-art parallel computers allow performing MD simulations not only with substantial number of particles, but also using of complicated computationally intense many-body potentials of the interatomic interactions. One of the most important tasks for the computer-aided material science is accurate and extensive characterization of thermodynamic properties of the materials. An essential part of this characterization is the prediction of phase

130

Modeling and Validation of a Fuel Cell Hybrid Vehicle  

E-Print Network (OSTI)

This paper describes the design and construction of a fuel cell hybrid electric vehicle based on the conversion of a five passenger production sedan. The vehicle uses a relatively small fuel cell stack to provide average power demands, and a battery pack to provide peak power demands for varied driving conditions. A model of this vehicle was developed using ADVISOR, an A__dvanced Vehicle Simulator that tracks energy flow and fuel usage within the vehicle drivetrain and energy conversion components.

Michael J. Ogburn; Douglas J. Nelson; Keith Wipke; Tony Markel

2000-01-01T23:59:59.000Z

131

Development of a Heavy-Duty Diesel Modal Emissions and Fuel Consumption Model  

E-Print Network (OSTI)

Modal Emissions and Fuel Consumption Model 2. Brown, S. ,Modal Emissions and Fuel Consumption Model Clark, N. N. andModal Emissions and Fuel Consumption Model 4.6. E XHAUST A

Barth, Matthew; Younglove, Theodore; Scora, George

2005-01-01T23:59:59.000Z

132

PHASE TRANSITIONS, CRITICAL PHENOMENA AND EXACTLY SOLVABLE LATTICE MODELS  

E-Print Network (OSTI)

in a pond change phase from a liquid state to solid ice. Lastly, if a horseshoe magnet is heated T100 C L G Figure 1. Schematic phase diagram of water showing the solid ice, liquid and gasPHASE TRANSITIONS, CRITICAL PHENOMENA AND EXACTLY SOLVABLE LATTICE MODELS Paul A. Pearce1

Pearce, Paul A.

133

Materials Modeling and Simulation for Nuclear Fuels (MMSNF) Workshops  

NLE Websites -- All DOE Office Websites (Extended Search)

Aerial photo of Argonne National Laboratory Argonne National Laboratory University of Chicago Chicago Photography courtesy Thomas F Ewing Privacy and Security Notice The MMSNF Workshops The goal of the Materials Modeling and Simulation for Nuclear Fuels (MMSNF) workshops is to stimulate research and discussions on modeling and simulations of nuclear fuels, to assist the design of improved fuels and the evaluation of fuel performance. In addition to research focused on existing or improved types of LWR reactors, recent modeling programs, networks, and links have been created to develop innovative nuclear fuels and materials for future generations of nuclear reactors. Examples can be found in Europe (e.g. F-BRIDGE project and ACTINET network and SAMANTHA cooperative network), in the USA (e.g. CASL, NEAMS, CESAR and CMSN network

134

A Thermal Model to Evaluate Sub-Freezing Startup for a Direct Hydrogen Hybrid Fuel Cell Vehicle Polymer Electrolyte Fuel Cell Stack and System  

E-Print Network (OSTI)

V Solid Polymer Electrolyte Fuel Cell, I. Mechanistic ModelI V Solid Polymer Electrolyte Fuel Cell, II. Empirical Modelexchange membrane fuel cells," Journal of Power Sources,

Sundaresan, Meena

2004-01-01T23:59:59.000Z

135

A Thermal Model to Evaluate Sub-Freezing Startup for a Direct Hydrogen Hybrid Fuel Cell Vehicle Polymer Electrolyte Fuel Cell Stack and System  

E-Print Network (OSTI)

IV Solid Polymer Electrolyte Fuel Cell, I. Mechanistic ModelIV Solid Polymer Electrolyte Fuel Cell, II. Empirical Modelexchange membrane fuel cells," Journal of Power Sources,

Sundaresan, Meena

2004-01-01T23:59:59.000Z

136

PYRO, a system for modeling fuel reprocessing  

Science Conference Proceedings (OSTI)

Compact, on-site fuel reprocessing and waste management for the Integral Fast Reactor are based on the pyrochemical reprocessing of metal fuel. In that process, uranium and plutonium in spent fuel are separated from fission products in an electrorefiner using liquid cadmium and molten salt solvents. Quantitative estimates of the distribution of the chemical elements among the metal and salt phases are essential for development of both individual pyrochemical process steps and the complete process. This paper describes the PYRO system of programs used to generate reliable mass flows and compositions.

Ackerman, J.P.

1989-01-01T23:59:59.000Z

137

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

SciTech Connect

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.

Not Available

1994-07-01T23:59:59.000Z

138

Lumped-parameter fuel rod model for rapid thermal transients  

SciTech Connect

The thermal behavior of fuel rods during simulated accident conditions is extremely sensitive to the heat transfer coefficient which is, in turn, very sensitive to the cladding surface temperature and the fluid conditions. The development of a semianalytical, lumped-parameter fuel rod model which is intended to provide accurate calculations, in a minimum amount of computer time, of the thermal response of fuel rods during a simulated loss-of-coolant accident is described. The results show good agreement with calculations from a comprehensive fuel-rod code (FRAP-T) currently in use at Aerojet Nuclear Company. (auth)

Perkins, K.R.; Ramshaw, J.D.

1975-07-01T23:59:59.000Z

139

Kinetic Modeling of Combustion Characteristics of Real Biodiesel Fuels  

DOE Green Energy (OSTI)

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.

Naik, C V; Westbrook, C K

2009-04-08T23:59:59.000Z

140

Modeling of polymer electrolyte fuel cell systems  

DOE Green Energy (OSTI)

Propulsion systems based on the polymer electrolyte fuel cell (PEFC) are being developed. This paper reports an analysis undertaken to design improved PEFC systems. A reference system design with some variants were set up for a methanol-fueled PEFC propulsion system. Efficiency improves from 38.4 to 44.1% as cell current density goes from 0.75 to 0.45 A/cm{sup 2}, while fuel cell efficiency increases from 52.6 to 60.0%; to get a net power output of 80 kWe, the active fuel cell area must increase from 18.8 to 27.3 m{sup 2}. Three parametric studies were conducted on the off-design performance of the reference system.

Kumar, R.; Ahluwalia, R.; Geyer, H.K.; Krumpelt, M.

1993-09-01T23:59:59.000Z

Note: This page contains sample records for the topic "fuels modeling transition" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


141

Clean air program: Design guidelines for bus transit systems using liquefied petroleum gas (LPG) as an alternative fuel. Final report, July 1995-April 1996  

Science Conference Proceedings (OSTI)

The Federal Transit Administration (FTA) has initiated the development of `Design Guidelines for Bus Transit Systems Using Alternative Fuels.` This report provides design guidelines for the safe uses of Liquefied Petroleum Gas (LPG). It forms a part of the series of individual monographs being published by the FTA on (the guidelines for the safe use of) Compressed Natural Gas (CNG), Liquefied Natural Gas (LNG), Liquefied Petroleum Gas (LPG) and alcohol fuels (Methanol and Ethanol). Each report in this series describes for the subject fuel the important fuel properties, guidelines for the design and operation of bus fueling, storage and maintenance facilities, issues on personnel training and emergency preparedness.

Raj, P.K.; Hathaway, W.T.; Kangas, R.

1996-09-01T23:59:59.000Z

142

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

E-Print Network (OSTI)

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 ...

Beccherle, Julien

2007-01-01T23:59:59.000Z

143

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

E-Print Network (OSTI)

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

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

2010-01-01T23:59:59.000Z

144

Model documentation: Electricity Market Module, Electricity Fuel Dispatch Submodule  

SciTech Connect

This report documents the objectives, analytical approach and development of the National Energy Modeling System Electricity Fuel Dispatch Submodule (EFD), a submodule of the Electricity Market Module (EMM). The report catalogues and describes the model assumptions, computational methodology, parameter estimation techniques, model source code, and forecast results generated through the synthesis and scenario development based on these components.

Not Available

1994-04-08T23:59:59.000Z

145

Modeling PWR Fuel Corrosion Product Deposition and Growth Process  

Science Conference Proceedings (OSTI)

This report describes further developments to the crud chemistry model developed in 2003. This model calculates the thermal and chemical conditions within fuel crud deposits. The model was developed to understand fuel crud scrape observations and help alleviate AOA in plants suffering this problem. The model predicts the main form of boron in thick crud (30m) is precipitated LiBO2. This precipitates because Li and boric acid concentrate in the bottom of the deposit due to evaporation. The rise in temper...

2005-09-26T23:59:59.000Z

146

Boiler Water Deposition Model for Fossil-Fueled Power Plants  

Science Conference Proceedings (OSTI)

The feasibility and initial development of an integrated, deterministic model of the various processes governing deposition in fossil boilers was assessed in the following Electric Power Research Institute (EPRI) reports: 1004931, Boiler Water Deposition Model: Part 1: Feasibility Study, published in 2004; 1012207, Boiler Water Deposition Model for Fossil Fuel Plants, Part 2: Initial Deterministic Model Development and Deposit Characterization, published in 2007; 1014128, Boiler Water Deposition Model fo...

2010-01-27T23:59:59.000Z

147

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

DOE Green Energy (OSTI)

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

Steward, D.; Penev, M.

2010-03-30T23:59:59.000Z

148

Loss of spent fuel pool cooling PRA: Model and results  

Science Conference Proceedings (OSTI)

This letter report documents models for quantifying the likelihood of loss of spent fuel pool cooling; models for identifying post-boiling scenarios that lead to core damage; qualitative and quantitative results generated for a selected plant that account for plant design and operational practices; a comparison of these results and those generated from earlier studies; and a review of available data on spent fuel pool accidents. The results of this study show that for a representative two-unit boiling water reactor, the annual probability of spent fuel pool boiling is 5 {times} 10{sup {minus}5} and the annual probability of flooding associated with loss of spent fuel pool cooling scenarios is 1 {times} 10{sup {minus}3}. Qualitative arguments are provided to show that the likelihood of core damage due to spent fuel pool boiling accidents is low for most US commercial nuclear power plants. It is also shown that, depending on the design characteristics of a given plant, the likelihood of either: (a) core damage due to spent fuel pool-associated flooding, or (b) spent fuel damage due to pool dryout, may not be negligible.

Siu, N.; Khericha, S.; Conroy, S.; Beck, S.; Blackman, H.

1996-09-01T23:59:59.000Z

149

Alternative Liquid Fuels Simulation Model (AltSim).  

Science Conference Proceedings (OSTI)

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.

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

150

The FIT Model - Fuel-cycle Integration and Tradeoffs  

Science Conference Proceedings (OSTI)

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.

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

151

TAFV Alternative Fuels and Vehicles Choice Model Documentation  

DOE Green Energy (OSTI)

A model for predicting choice of alternative fuel and among alternative vehicle technologies for light-duty motor vehicles is derived. The nested multinomial logit (NML) mathematical framework is used. Calibration of the model is based on information in the existing literature and deduction based on assuming a small number of key parameters, such as the value of time and discount rates. A spreadsheet model has been developed for calibration and preliminary testing of the model.

Greene, D.L.

2001-07-27T23:59:59.000Z

152

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

SciTech Connect

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.

Battelle

2000-06-30T23:59:59.000Z

153

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

E-Print Network (OSTI)

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. ...

La O', Gerardo Jose Cordova

2008-01-01T23:59:59.000Z

154

Heat Transfer Modeling of Dry Spent Nuclear Fuel Storage Facilities  

Science Conference Proceedings (OSTI)

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.

Lee, S.Y.

1999-01-13T23:59:59.000Z

155

Kinetic Modeling of Toluene Oxidation for Surrogate Fuel Applications  

SciTech Connect

New environmental issues, like the effect of combustion-generated greenhouse gases, provide motivation to better characterize oxidation of hydrocarbons. Transportation, in particular, significantly contributes to energy consumption and CO{sub 2} emissions. Kinetic studies about the combustion of fuels under conditions typical of internal combustion engines provides important support to improve mechanism formulation and to eventually provide better computational tools that can be used to increase the engine performance. It is foreseeable that at least in the next 30 years the main transportation fuels will be either gasoline or diesel. Unfortunately, these fuels are very complex mixtures of many components. Moreover, their specifications and performance requirements significantly change the composition of these fuels: gasoline and diesel mixtures are different if coming from different refineries or they are different from winter to summer. At the same time a fuel with a well defined and reproducible composition is needed for both experimental and modeling work. In response to these issues, surrogate fuels are proposed. Surrogate fuels are defined as mixtures of a small number of hydrocarbons whose relative concentrations is adjusted in order to approximate the chemical and physical properties of a real fuel. Surrogate fuels are then very useful both for the design of reproducible experimental tests and also for the development of reliable kinetic models. The primary reference fuels (PRF) are a typical and old example of surrogate fuel: n-heptane and iso-octane mixtures are used to reproduce antiknock propensity of complex mixtures contained in a gasoline. PRFs are not able to surrogate gasoline in operating conditions different from standard ones and new surrogates have been recently proposed. Toluene is included in all of them as a species able to represent the behavior of aromatic compounds. On the other side, the toluene oxidation chemistry is not so well established and uncertainties still remain in the mechanism. This is especially true in the low temperature regime (< 850K). In these conditions, the toluene reactivity is too low to be conveniently investigated. Nonetheless, gasoline surrogates work in the engine at low temperatures, because of the presence of very reactive alkanes. The effect of these component interactions have to be taken into account. This work's aim is to present the model activity carried out by two different research groups, comparing the main pathways and results, matching data carried out in different devices both for pure toluene and mixtures. This is the starting point for a further activity to improve the two kinetic schemes.

Frassoldati, A; Mehl, M; Fietzek, R; Faravelli, T; Pitz, W J; Ranzi, E

2009-04-21T23:59:59.000Z

156

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

DOE Green Energy (OSTI)

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

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

2007-09-01T23:59:59.000Z

157

Sustainable energy for developing countries : modelling transitions to renewable and clean energy in rapidly developing countries.  

E-Print Network (OSTI)

??The main objective of this thesis is first to adapt energy models for the use in developing countries and second to model sustainable energy transitions (more)

Urban, Frauke

2009-01-01T23:59:59.000Z

158

Transition Events in Butane Simulations: Similarities Across Models  

E-Print Network (OSTI)

From a variety of long simulations of all-atom butane using both stochastic and fully-solved molecular dynamics, we have uncovered striking generic behavior which also occurs in one-dimensional systems. We find an apparently universal distribution of transition event durations, as well as a characteristic speed profile along the reaction coordinate. An approximate analytic distribution of event durations, derived from a one-dimensional model, correctly predicts the asymptotic behavior of the universal distribution for both short and long durations. 1 1

Daniel M. Zuckerman; Thomas B. Woolf

2008-01-01T23:59:59.000Z

159

Transition Events in Butane Simulations Similarities Across Models  

E-Print Network (OSTI)

From a variety of long simulations of all-atom butane using both stochastic and fully-solved molecular dynamics, we have uncovered striking generic behavior which also occurs in one-dimensional systems. We find an apparently universal distribution of transition event durations, as well as a characteristic speed profile along the reaction coordinate. An approximate analytic distribution of event durations, derived from a one-dimensional model, correctly predicts the asymptotic behavior of the universal distribution for both short and long durations.

Zuckerman, D M; Zuckerman, Daniel M.; Woolf, Thomas B.

2001-01-01T23:59:59.000Z

160

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

E-Print Network (OSTI)

the compression stroke. The residues calculated from the proposed model were validated with those generated from to detect the fuel ethanol concentration by placing them in the tank or in the fuel line. However by means of the closed-loop air/fuel ratio correction signal based on the Exhaust Gas Oxygen (EGO) sensor

Stefanopoulou, Anna

Note: This page contains sample records for the topic "fuels modeling transition" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


161

Modeling Tools for Solid Oxide Fuel Cell Analysis  

NLE Websites -- All DOE Office Websites (Extended Search)

Tools for Solid Oxide Fuel Tools for Solid Oxide Fuel Cell Design and Analysis Moe A Khaleel BJ Koeppel, W Liu, K Lai, KP Recknagle, EM Ryan, EV Stephens, X Sun Pacific Northwest National Laboratory Richland, WA 99352 11 th Annual SECA Workshop Pittsburgh, PA July 27-29, 2009 1 PNNL SOFC Modeling Tools SOFC-MP Stack level model for fast analysis of co/counter-flow SOFC stack performance Detailed electrochemistry model Cell level model for the investigation of secondary reactions (degradation/contamination) mechanisms within the tri-layer Component-based design and performance modeling Contact material Interconnect Glass seal 2 SOFC-MP Stack Simulation Code Recent Accomplishments Major memory improvements of 3D model to accommodate 50-cell stacks on LINUX platform. Previously, developed a 2D (or stacked

162

Renewable Fuels Module, Appendix - Model Performance, Model Documentation  

Reports and Publications (EIA)

This appendix discusses performance aspects of the Renewable Fuels Module (RFM). It is intended to present the pattern of response of the RFM to typical changes in its major inputs from other NEMS modules.

Perry M. Lindstrom

1995-06-01T23:59:59.000Z

163

Application of alternating current impedance to fuel cell modeling  

DOE Green Energy (OSTI)

AC impedance has provided a useful diagnostic tool in the Los Alamos polymer electrolyte fuel cell (PEFC) program. The author reviews the techniques he has used in ac impedance modeling. These techniques include equation implementation, model simplification and verification, least squares fitting, application of two-dimensional Laplace equation solvers handling complex interfacial boundary conditions, and interpretation of impedance features. The separate features of the complete electrode model are explained by analytic examples.

Springer, T.E.

1999-05-02T23:59:59.000Z

164

Clean air program: Design guidelines for bus transit systems using hydrogen as an alternative fuel. Final report, September 1997--May 1998  

SciTech Connect

Alternative fuels such as Compressed Natural Gas (CNG), Liquefied Natural Gas (LNG), Liquified Petroleum Gas (LPG), and alcohol fuels (methanol and ethanol) are already being used in commercial vehicles and transit buses in revenue service. Hydrogen, which has better air quality characteristics as a vehicle fuel, is being used in research demonstration projects in fuel cell powered buses, as well as in internal combustion engines in automobiles and small trucks. At present, there are no facility guidelines to assist transit agencies (and others) contemplating the use of hydrogen as an alternative fuel. This document addresses the various issues involved. Hydrogen fuel properties, potential hazards, fuel requirements for specified levels of bus service, applicable codes and standards, ventilation, and electrical classification are indicated in this document. These guidelines also present various facility and bus design issues that need to be considered by a transit agency to ensure safe operations when using hydrogen as an alternative fuel. Fueling facility, garaging facility, maintenance facility requirements and safety practices are discussed. Critical fuel-related safety issues in the design of the related system on the bus are also identified. A system safety assessment and hazard resolution process is also presented. This approach may be used to select design strategies which are economical, yet ensure a specified level of safety.

Raj, P.K.; Hathaway, W.T.; Kangas, R.A.

1998-10-01T23:59:59.000Z

165

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

SciTech Connect

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 a

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

166

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

DOE Green Energy (OSTI)

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

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

167

2008 Model Fuel Cell Car Competition  

NLE Websites -- All DOE Office Websites (Extended Search)

Model Car Competition Regional Structure Design Competition Structure Judges will grade one car from each school. Each judge can give up to 35 points per car as follows:...

168

Shell model transition densities for electron and pion scattering  

Science Conference Proceedings (OSTI)

The general features of an effective interaction suitable for the calculation of cross-shell matrix elements in the /sup 16/O region are discussed. Shell-model transition densities are applied to the 1 hw excitation of non-normal parity states in light-nuclei, with /sup 13/C used as a prime example. The longitudinal form factors from such a calculation require enhancement and transverse form factors (spin-excitations) need to be quenched. The shapes of form factors also exhibit systematic discrepancies which are correlated with the discrepancies in magnitude. The problem with shapes is particularly marked for C1 form factors. It is shown that the addition of small components to the transition density, corresponding to the excitation of a single particle through two or three major shells, works in the right direction as far as both magnitude and shape are concerned and that such additions are particularly effective in the case of C1 excitations. For the transverse form factors in /sup 13/C, the use of Woods-Saxon radial wave functions leads to reductions of up to 50% compared with harmonic oscillator wave functions. The excitation of states with dominant multiparticle-multihole components, and the role played by admixtures of such configurations in low-lying states, is considered. Some of the problems associated with the use of shell-model bases extended to include high-lying configurations in the giant resonance region are pointed out. 15 refs., 15 figs., 1 tab.

Millener, D.J.

1987-01-01T23:59:59.000Z

169

Digital herders and phase transition in a voting model  

E-Print Network (OSTI)

In this paper, we discuss a voting model with two candidates, $C_1$ and $C_2$. We set two types of voters--herders and independents. The voting of independent voters is based on their fundamental values; on the other hand, the voting of herders is based on the number of votes. Herders always select the majority of the previous $r$ votes, which is visible to them. We call them digital herders. We can accurately calculate the distribution of votes for special cases. When $r\\geq 3$, we find that a phase transition occurs at the upper limit of $t$, where $t$ is the discrete time (or number of votes). As the fraction of herders increases, the model features a phase transition beyond which a state where most voters make the correct choice coexists with one where most of them are wrong. On the other hand, when $rperformance is the same as that of the independent voters. At last, from the simple experiments, we recognize the behavior of human beings.

Hisakado, Masato

2011-01-01T23:59:59.000Z

170

Metal-Insulator Transitions in Degenerate Hubbard Models and  

E-Print Network (OSTI)

Mott-Hubbard metal-insulator transitions in N-fold degenerate Hubbard models are studied within the Gutzwiller approximation. For any rational filling with x (integer) electrons per site it is found that metal-insulator transition occurs at a critical correlation energy Uc(N,x) = Uc(N,2N ? x) = ?(N,x)|?(N,x)|, where ? is the band energy per particle for the uncorrelated Fermi-liquid state and ?(N,x) is a geometric factor which increases linearly with x. We propose that the alkali metal doped fullerides AxC60 can be described by a 3-fold degenerate Hubbard model. Using the current estimate of band width and correlation energy this implies that most of AxC60, at integer x, are Mott-Hubbard insulators and A3C60 is a strongly correlated metal. PACS numbers: 71.10.+x,71.30.+h,74.70.W 1 Typeset using REVTEXThe discovery of superconductivity in A3C60 [1] has spurred great interest in alkali metal doped fullerides [2]. Beside A3C60, stable phases such as Rb1C60, Na2C60, K4C60 were

Jian Ping Lu

2008-01-01T23:59:59.000Z

171

Model Year 2013: Alternative Fuel Vehicles and Advanced Technology Vehicles  

Alternative Fuels and Advanced Vehicles Data Center (EERE)

13: Alternative Fuel and Advanced Technology Vehicles 13: Alternative Fuel and Advanced Technology Vehicles 1 (Updated 3/6/13) 1 Source: http:/afdc.energy.gov/vehicles/search/light/ Fuel/Powertrain Type Make Model Vehicle Type Engine Size/Cylinders Transmission Emissions Class 2 Fuel Economy Gasoline 3,4 City/Hwy Fuel Economy Alt Fuel 3,4 City/Hwy HEV Acura ILX Sedan 1.5L I4 ECVT Tier 2 Bin 3 LEVII PZEV 39 / 38 N/A FFV E85 Audi A4 Sedan 2.0 I4 Auto Tier 2 Bin 5 LEVII ULEV 20 / 29 14 / 20 FFV E85 Audi A5 Sedan 2.0 I4 Auto Tier 2 Bin 5 LEVII ULEV 20 / 29 14 / 20 FFV E85 Audi A5 Cabriolet Sedan 2.0 I4 Auto Tier 2 Bin 5 LEVII ULEV 20 / 29 14 / 20 FFV E85 Audi Allroad Quatro Wagon 2.0 I4 Auto Tier 2 Bin 5 LEVII ULEV 20 / 27 14 / 18 FFV E85 Audi Q5 SUV 2.0 I4 Auto Tier 2 Bin 5 LEVII ULEV 20 / 28 14 / 19 HEV Audi Q5 Hybrid SUV 2.0 I4 Auto Tier 2 Bin 5 LEVII ULEV 24 / 30 N/A FFV E85 Bentley

172

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

DOE Green Energy (OSTI)

As described in the Department of Energy Office of Nuclear Energys 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 nations energy security through more effective utilization of our countrys 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.

David Petti; J. Stephen Herring

2010-03-01T23:59:59.000Z

173

Handbook of SiC Properties for Fuel Performance Modeling  

SciTech Connect

The SiC layer integrity in the TRISO-coated gas-reactor fuel particle is critical to the performance, allowed burn-up, and hence intrinsic efficiency of high temperature gas cooled reactors. While there has been significant developmental work on manufacturing the fuel particles, detailed understanding of what effects the complex in-service stress state combined with realistic materials property data under irradiation has on fuel particle survival is not adequately understood. This fact particularly frustrates the modeling efforts that seek to improve fuel performance through basic understanding. In this work the properties of SiC in the non-irradiated and irradiated condition are reviewed and analyzed in terms of applicability to TRISO fuel modeling. In addition to a review of literature data, new data has been generated to fill-in holes in the existing database, specifically in the high-temperature irradiation regime. Another critical piece of information, the strength of the SiC/Pyrolytic carbon interface, is measured and a formalism for its analysis presented. Finally, recommended empirical treatments of the data are suggested.

Snead, Lance Lewis [ORNL; Nozawa, Takashi [ORNL; Katoh, Yutai [ORNL; Byun, Thak Sang [ORNL; Kondo, Sosuke [ORNL; Petti, David [Idaho National Laboratory (INL)

2007-01-01T23:59:59.000Z

174

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

SciTech Connect

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.

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

175

Parallel Graph Transformation for Model Simulation applied to Timed Transition Petri Nets  

Science Conference Proceedings (OSTI)

This work discusses the use of parallel graph transformation systems for (multi-formalism) modeling and simulation and their implementation in the meta-modeling tool AToM^3. As an example, a simulator for Timed Transition Petri Nets (TTPN) is modeled ... Keywords: model simulation, parallel graph transformation, timed transition Petri nets

J. de Lara; C. Ermel; G. Taentzer; K. Ehrig

2004-12-01T23:59:59.000Z

176

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

E-Print Network (OSTI)

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

Brandt, Adam R.; Farrell, Alexander E.

2008-01-01T23:59:59.000Z

177

Modeling PWR Fuel Corrosion Product Deposition and Growth Processes  

Science Conference Proceedings (OSTI)

Development of axial offset anomaly (AOA) in pressurized water reactors (PWRs) drove industry to conduct crud scrape campaigns at a number of units to characterize and better understand the material being deposited on the fuel clad surface. This report describes the first phase of a program to develop models that describe the crud deposition and growth process, including the many phenomena that influence not only the deposit mass, but the composition. The models will be benchmarked against published crud...

2004-12-09T23:59:59.000Z

178

Pacific Northwest Laboratory (PNL) spent fuel transportation and handling facility models  

SciTech Connect

A spent fuel logistics study was conducted in support of the US DOE program to develop facilities for preparing spent unreprocessed fuel from commercial LWRs for geological storage. Two computerized logistics models were developed. The first one was the site evaluation model. Two studies of spent fuel handling facility and spent fuel disposal facility siting were completed; the first postulates a single spent fuel handling facility located at any of six DOE laboratory sites, while the second study examined siting strategies with the spent fuel repository relative to the spent fuel handling facility. A second model to conduct storage/handling facility simulations was developed. (DLC)

Andrews, W.B.; Bower, J.C.; Burnett, R.A.; Engel, R.L.; Rolland, C.W.

1979-09-01T23:59:59.000Z

179

Fuel Cell Technologies Office: Transport Modeling Working Group  

NLE Websites -- All DOE Office Websites (Extended Search)

Transport Modeling Working Group Transport Modeling Working Group The Transport Modeling Working Group meets twice per year to exchange information, create synergies, share experimental and computational results, and collaboratively develop methodologies for and understanding of transport phenomena in polymer electrolyte fuel cell stacks. Its members include principle investigators and supporting personnel from transport-related projects funded by the U.S. Department of Energy (DOE). Learn more about DOE research activities can be found in the Multi-Year Research, Development, and Demonstration Plan. Description Technical Targets Meetings Contacts Description Fuel cell operation relies on effective mass transport of species through individual components and across the interfaces between components. Among these species are hydrogen, oxygen, water, protons, and electrons. Transport behavior is a function of operating conditions and component properties such as microstructure and surface properties. Understanding and optimizing the controlling transport phenomena are critical to the efficient and cost-effective operation of polymer electrolyte fuel cells. A better understanding of mass transport in the fuel cell, especially of water, has the potential to lead to improved designs and more efficient systems.

180

Model Year 2006: Alternative Fuel and Advanced Technology Vehicles  

Alternative Fuels and Advanced Vehicles Data Center (EERE)

06: Alternative Fuel and Advanced Technology Vehicles 06: Alternative Fuel and Advanced Technology Vehicles Fuel Type EPAct Compliant? Model Vehicle Type Emission Class Powertrain Fuel Capacity Range American Honda Motor Corporation 888-CCHONDA www.honda.com CNG Dedicated EPAct Yes Civic GX Compact Sedan SULEV Tier 2 Bin II 1.7L, 4-cylinder 8 GGE 200 mi HEV (NiMH) EPAct No Accord Hybrid Sedan ULEV 3.0L V6 144 volt NiMH + 17.1 Gal Gasoline TBD HEV (NiMH) EPAct No Civic Hybrid Sedan CA ULEV 1.3L, 4-cylinder 144 volt NiMH + 13.2 Gal Gasoline TBD HEV (NiMH) EPAct No Insight Two-seater SULEV (CVT model) ULEV (MT model) 1.0L, 3-cylinder 144 volt NiMH + 10.6 Gal Gasoline 636 mi DaimlerChrysler 800-999-FLEET www.fleet.chrysler.com E85 FFV EPAct Yes Dodge Ram Pickup 1500 Series 1 Pickup Tier 2 Bin 10A 4.7L V8 26 Gal 416 mi E85 FFV

Note: This page contains sample records for the topic "fuels modeling transition" from the National Library of EnergyBeta (NLEBeta).
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181

Transition from HEU to LEU fuel in Romania`s 14-MW TRIGA reactor  

SciTech Connect

The 14-MW TRIGA steady state reactor (SSR) located in Pitesti, Romania, first went critical in the fall of 1979. Initially, the core configuration for full power operation used 29 fuel clusters each containing a 5 {times} 5 square array of HEU (10 wt%) -- ZrH -- Er (2.8 wt%) fuel-moderator rods (1.295 cm o.d.) clad in Incology. With a total inventory of 35 HEU fuel clusters, burnup considerations required a gradual expansion of the core from 29 to 32 and finally to 35 clusters before the reactor was shut down because of insufficient excess reactivity. At this time each of the original 29 fuel clusters had an overage {sup 235}U burnup in the range from 50 to 62%. Because of the US policy regarding the export of highly enriched uranium, fresh HEU TRIGA replacement fuel is not available. After a number of safety-related measurements, the SSR is expected to resume full power operation in the near future using a mixed core containing five LEU TRIGA clusters of the same geometry as the original fuel but with fuel-moderator rods containing 45 wt% U (19.7% {sup 235}U enrichment) and 1.1 wt% Er. Rods for 14 additional LEU fuel clusters will be fabricated by General Atomics. In support of the SSR mixed core operation numerous neutronic calculations have been performed. This paper presents some of the results of those calculations.

Bretscher, M.M.; Snelgrove, J.L.

1991-12-31T23:59:59.000Z

182

Modeling and cold start in alcohol-fueled engines  

DOE Green Energy (OSTI)

Neat alcohol fuels offer several benefits over conventional gasoline in automotive applications. However, their low vapor pressure and high heat of vaporization make it difficult to produce a flammable vapor composition from a neat alcohol fuel during a start under cold ambient conditions. Various methods have been introduced to compensate for this deficiency. In this study, the authors applied computer modeling and simulation to evaluate the potential of four cold-start technologies for engines fueled by near-neat alcohol. The four technologies were a rich combustor device, a partial oxidation reactor, a catalytic reformer, and an enhanced ignition system. The authors ranked the competing technologies by their ability to meet two primary criteria for cold starting an engine at {minus}25 deg C and also by several secondary parameters related to commercialization. Their analysis results suggest that of the four technologies evaluated, the enhanced ignition system is the best option for further development.

Markel, A.J.; Bailey, B.K.

1998-05-01T23:59:59.000Z

183

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

E-Print Network (OSTI)

fuel use. Mesoscale Modeling Data Set and Mesoscale Modelobserved, quantified in the data set, and modeled to improveerrors for the validation data set are less than 2% for fuel

Scora, George Alexander

2011-01-01T23:59:59.000Z

184

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

E-Print Network (OSTI)

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 ...

Bonnet, Nicphore

2007-01-01T23:59:59.000Z

185

Macroscopic Modeling of the Proton-Exchange-Membrane Fuel-Cell...  

NLE Websites -- All DOE Office Websites (Extended Search)

Macroscopic Modeling of the Proton-Exchange-Membrane Fuel-Cell Catalyst Layer Title Macroscopic Modeling of the Proton-Exchange-Membrane Fuel-Cell Catalyst Layer Publication Type...

186

MODELING AND DESIGN FOR A DIRECT CARBON FUEL CELL WITH ENTRAINED FUEL AND OXIDIZER  

DOE Green Energy (OSTI)

The novel molten carbonate fuel cell design described in this report uses porous bed electrodes. Molten carbonate, with carbon fuel particles and oxidizer entrained, is circulated through the electrodes. Carbon may be reacted directly, without gasification, in a molten carbonate fuel cell. The cathode reaction is 2CO{sub 2} + O{sub 2} 4e{sup -} {yields} 2CO{sub 3}{sup =}, while the anode reaction can be either C + 2CO{sub 3}{sup =} {yields} 3CO{sub 2} + 4e{sup -} or 2C + CO{sub 3}{sup =} {yields} 3CO + 2e{sup -}. The direct carbon fuel cell has an advantage over fuel cells using coal-derived synthesis gas in that it provides better overall efficiency and reduces equipment requirements. Also, the liquid electrolyte provides a means for transporting the solid carbon. The porous bed cell makes use of this carbon transport ability of the molten salt electrolyte. A one-dimensional model has been developed for predicting the performance of this cell. For the cathode, dependent variables are superficial O{sub 2} and CO{sub 2} fluxes in the gas phase, superficial O{sub 2} and CO{sub 2} fluxes in the liquid phase, superficial current density through the electrolyte, and electrolyte potential. The variables are related by correlations, from the literature, for gas-liquid mass transfer, liquid-solid mass transfer, cathode current density, electrode overpotential, and resistivity of a liquid with entrained gas. For the anode, dependent variables are superficial CO{sub 2} flux in the gas phase, superficial CO{sub 2} flux in the liquid phase, superficial C flux, superficial current density through the electrolyte, and electrolyte potential. The same types of correlations relate the variables as in the cathode, with the addition of a correlation for resistivity of a fluidized bed. CO production is not considered, and axial dispersion is neglected. The model shows behavior typical of porous bed electrodes used in electrochemical processes. Efficiency is comparable to that of membrane electrode fuel cells. Effective bed depths are on the order of 1-5 centimeter, giving power/volume lower than for membrane electrode cells. The porous bed design, however, uses less expensive materials and is more resistant to fouling by coal impurities. The model will be used in the second phase of the project to design a laboratory-scale prototype cell. The prototype cell will demonstrate the concept and provide experimental data for improving the model.

Alan A. Kornhauser; Ritesh Agarwal

2005-04-01T23:59:59.000Z

187

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

E-Print Network (OSTI)

TRISO-coated Particle Nuclear Fuel Performance Models, Rareet al. , A Sustainable Nuclear Fuel Cycle Based on LaserC.D. Heising, Closing the Nuclear Fuel Cycle: Thorium and

Powers, Jeffrey

2011-01-01T23:59:59.000Z

188

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

DOE Green Energy (OSTI)

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

Not Available

2012-08-01T23:59:59.000Z

189

MODELING THE PERFORMANCE OF HIGH BURNUP THORIA AND URANIA PWR FUEL  

E-Print Network (OSTI)

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

Long, Y.

190

Development of Detailed Kinetic Models for Fischer-Tropsch Fuels  

DOE Green Energy (OSTI)

Fischer-Tropsch (FT) fuels can be synthesized from a syngas stream generated by the gasification of biomass. As such they have the potential to be a renewable hydrocarbon fuel with many desirable properties. However, both the chemical and physical properties are somewhat different from the petroleum-based hydrocarbons that they might replace, and it is important to account for such differences when considering using them as replacements for conventional fuels in devices such as diesel engines and gas turbines. FT fuels generally contain iso-alkanes with one or two substituted methyl groups to meet the pour-point specifications. Although models have been developed for smaller branched alkanes such as isooctane, additional efforts are required to properly capture the kinetics of the larger branched alkanes. Recently, Westbrook et al. developed a chemical kinetic model that can be used to represent the entire series of n-alkanes from C{sub 1} to C{sub 16} (Figure 1). In the current work, the model is extended to treat 2,2,4,4,6,8,8-heptamethylnonane (HMN), a large iso-alkane. The same reaction rate rules used in the iso-octane mechanism were incorporated in the HMN mechanism. Both high and low temperature chemistry was included so that the chemical kinetic model would be applicable to advanced internal combustion engines using low temperature combustion strategies. The chemical kinetic model consists of 1114 species and 4468 reactions. Concurrently with this effort, work is underway to improve the details of specific reaction classes in the mechanism, guided by high-level electronic structure calculations. Attention is focused upon development of accurate rate rules for abstraction of the tertiary hydrogens present in branched alkanes and properly accounting for the pressure dependence of the ?-scission, isomerization, and R + O{sub 2} reactions.

Westbrook, C K; Pitz, W J; Carstensen, H; Dean, A M

2008-10-28T23:59:59.000Z

191

Numerical modeling of hydrogen-fueled internal combustion engines  

DOE Green Energy (OSTI)

The planned use of hydrogen as the energy carrier of the future introduces new challenges and opportunities, especially to the engine design community. Hydrogen is a bio-friendly fuel that can be produced from renewable resources and has no carbon dioxide combustion products; and in a properly designed ICE, almost zero NO{sub x} and hydrocarbon emissions can be achieved. Because of the unique properties of hydrogen combustion - in particular the highly wrinkled nature of the laminar flame front due to the preferential diffusion instability - modeling approaches for hydrocarbon gaseous fuels are not generally applicable to hydrogen combustion. This paper reports on the current progress to develop a engine design capability based on KIVA family of codes for hydrogen-fueled, spark-ignited engines in support of the National Hydrogen Program. A turbulent combustion model, based on a modified eddy-turnover model in conjunction with an intake flow valve model, is found to describe well the efficiency and NO{sub x} emissions of this engine satisfy the Equivalent Zero Emission Vehicle (EZEV) standard established by the California Resource Board. 26 refs., 10 figs., 1 tab.

Johnson, N.L.; Amsden, A.A.

1996-12-31T23:59:59.000Z

192

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

193

Barriers to a biofuels transition in the U.S. liquid fuels sector.  

E-Print Network (OSTI)

??Demand for liquid fuels (i.e., petroleum products) has burdened the U.S. with major challenges, including national security and economic concerns stemming from rising petroleum imports; (more)

O'Donnell, Michael Joseph

2010-01-01T23:59:59.000Z

194

Alcohol Transportation Fuels Demonstration Program  

DOE Green Energy (OSTI)

Hawaii has abundant natural energy resources, especially biomass, that could be used to produce alternative fuels for ground transportation and electricity. This report summarizes activities performed during 1988 to June 1991 in the first phase of the Alcohol Transportation Fuels Demonstration Program. The Alcohol Transportation Fuels Demonstration Program was funded initially by the Energy Division of the State of Hawaii's Department of Business, Economic Development and Tourism, and then by the US Department of Energy. This program was intended to support the transition to an altemative transportation fuel, methanol, by demonstrating the use of methanol fuel and methanol-fueled vehicles, and solving the problems associated with that fuel. Specific objectives include surveying renewable energy resources and ground transportation in Hawaii; installing a model methanol fueling station; demonstrating a methanol-fueled fleet of (spark-ignition engine) vehicles; evaluating modification strategies for methanol-fueled diesel engines and fuel additives; and investigating the transition to methanol fueling. All major objectives of Phase I were met (survey of local renewable resources and ground transportation, installation of methanol refueling station, fleet demonstration, diesel engine modification and additive evaluation, and dissemination of information on alternative fueling), and some specific problems (e.g., relating to methanol fuel contamination during handling and refueling) were identified and solved. Several key issues emerging from Phase I (e.g., methanol corrosion, flame luminosity, and methanol-transition technoeconomics) were recommended as topics for follow-on research in subsequent phases of this program.

Kinoshita, C.M. (ed.)

1990-01-01T23:59:59.000Z

195

TAFV Alternative Fuels and Vehicles Choice Model Documentation  

NLE Websites -- All DOE Office Websites (Extended Search)

34 34 ORNL/TM-2001/134 TAFV Alternative Fuels and TAFV Alternative Fuels and Vehicles Choice Model Vehicles Choice Model Documentation Documentation July 2001 David L. Greene David L. Greene Corporate Fellow Corporate Fellow DOCUMENT AVAILABILITY Reports produced after January 1, 1996, are generally available free via the U.S. Department of Energy (DOE) Information Bridge: Web site: http://www.osti.gov/bridge Reports produced before January 1, 1996, may be purchased by members of the public from the following source: National Technical Information Service 5285 Port Royal Road Springfield, VA 22161 Telephone: 703-605-6000 (1-800-553-6847) TDD: 703-487-4639 Fax: 703-605-6900 E-mail: info@ntis.fedworld.gov Web site: http://www.ntis.gov/support/ordernowabout.htm Reports are available to DOE employees, DOE contractors, Energy Technology Data Exchange

196

Model documentation Renewable Fuels Module of the National Energy Modeling System  

DOE Green Energy (OSTI)

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.

NONE

1996-01-01T23:59:59.000Z

197

Enabling Advanced Modeling and Simulations for Fuel-Flexible Combustors  

Science Conference Proceedings (OSTI)

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 tranformation 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.

Heinz Pitsch

2010-05-31T23:59:59.000Z

198

Recent Advances in Detailed Chemical Kinetic Models for Large Hydrocarbon and Biodiesel Transportation Fuels  

DOE Green Energy (OSTI)

n-Hexadecane and 2,2,4,4,6,8,8-heptamethylnonane represent the primary reference fuels for diesel that are used to determine cetane number, a measure of the ignition property of diesel fuel. With the development of chemical kinetics models for these two primary reference fuels for diesel, a new capability is now available to model diesel fuel ignition. Also, we have developed chemical kinetic models for a whole series of large n-alkanes and a large iso-alkane to represent these chemical classes in fuel surrogates for conventional and future fuels. Methyl decanoate and methyl stearate are large methyl esters that are closely related to biodiesel fuels, and kinetic models for these molecules have also been developed. These chemical kinetic models are used to predict the effect of the fuel molecule size and structure on ignition characteristics under conditions found in internal combustion engines.

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

2009-03-30T23:59:59.000Z

199

The National Energy Modeling System: An Overview 2000 - Renewable Fuels  

Gasoline and Diesel Fuel Update (EIA)

renewable fuels module (RFM) consists of five submodules that represent the various types of renewable energy technologies used for grid-connected U.S. electricity supply (Figure 11). Since most renewables (wind, solar, and geothermal) are used to generate electricity, the interaction with the electricity market module (EMM) is important for modeling grid-connected renewable-electric applications. The penetration of grid-connected generation technologies, with the exception of municipal solid waste, is determined by EMM. Hydropower is included in EMM directly. renewable fuels module (RFM) consists of five submodules that represent the various types of renewable energy technologies used for grid-connected U.S. electricity supply (Figure 11). Since most renewables (wind, solar, and geothermal) are used to generate electricity, the interaction with the electricity market module (EMM) is important for modeling grid-connected renewable-electric applications. The penetration of grid-connected generation technologies, with the exception of municipal solid waste, is determined by EMM. Hydropower is included in EMM directly. Figure 11. Renewable Fuels Module Structure Each submodule of RFM is solved independently of the rest. Because variable operation and maintenance costs for renewable technologies are lower than for any other major generating technology and they produce almost no air pollution, all available renewable generating capacity is dispatched first by EMM.

200

THERMODYNAMIC AND KINETIC MODELING OF ADVANCED NUCLEAR FUELS - FINAL LDRD-ER REPORT  

SciTech Connect

This project enhanced our theoretical capabilities geared towards establishing the basic science of a high-throughput protocol for the development of advanced nuclear fuel that should couple modern computational materials modeling and simulation tools, fabrication and characterization capabilities, and targeted high throughput performance testing experiments. The successful conclusion of this ER project allowed us to upgrade state-of-the-art modeling codes, and apply these modeling tools to ab initio energetics and thermodynamic assessments of phase diagrams of various mixtures of actinide alloys, propose a tool for optimizing composition of complex alloys for specific properties, predict diffusion behavior in diffusion couples made of actinide and transition metals, include one new equation in the LLNL phase-field AMPE code, and predict microstructure evolution during alloy coring. In FY11, despite limited funding, the team also initiated an experimental activity, with collaboration from Texas A&M University by preparing samples of nuclear fuels in bulk forms and for diffusion couple studies and metallic matrices, and performing preliminary characterization.

Turchi, P

2011-11-28T23:59:59.000Z

Note: This page contains sample records for the topic "fuels modeling transition" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


201

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

NLE Websites -- All DOE Office Websites (Extended Search)

Cycle Analysis of Hydrogen-Powered Cycle Analysis of Hydrogen-Powered Fuel-Cell Systems with the GREET Model Michael Wang Argonne National Laboratory June 10, 2008 Project ID # AN2 This presentation does not contain any proprietary, confidential, or otherwise restricted information 2 Overview * Project start date: Oct. 2002 * Project end date: Continuous * Percent complete: N/A * Inconsistent data, assumptions, and guidelines * Suite of models and tools * Unplanned studies and analyses * Total project funding from DOE: $2.04 million through FY08 * Funding received in FY07: $450k * Funding for FY08: $840k Budget * H2A team * PSAT team * NREL * Industry stakeholders Partners Timeline Barriers to Address 3 Objectives * Expand and update the GREET model for hydrogen production pathways and for applications of FCVs and other FC systems

202

Caloric curve for nuclear liquid-gas phase transition in relativistic mean-field hadronic model  

E-Print Network (OSTI)

The main thermodynamical properties of the nuclear liquid-gas phase transition were explored in the framework of the relativistic mean-field hadronic model in three statistical ensembles: canonical, grand canonical and isobaric. We have found that the liquid-gas phase transition, i.e., the first order phase transition which is defined by the plateau in the isotherms, cannot contain the plateau in the caloric curves in the canonical and microcanonical ensembles. The plateau in the isotherms is incompatible with the plateau in the caloric curves at fixed baryon density. Moreover, for the nuclear liquid-gas phase transition the caloric curve has a plateau only at fixed pressure or chemical potential. The results of the statistical multifragmentation models for the nuclear liquid-gas phase transition were reanalyzed. It was revealed that one class of statistical multifragmentation models do indeed predict the nuclear liquid-gas phase transition for the nuclear multifragmentation. However, there is another class o...

Parvan, A S

2011-01-01T23:59:59.000Z

203

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

E-Print Network (OSTI)

for CO2 evolved from oil shale. Fuel Processing Technology,E. T. and Miller, G. A. Oil shales and carbon dioxide.D. J. and Cecchine, G. Oil shale development in the United

Brandt, Adam R.; Farrell, Alexander E.

2008-01-01T23:59:59.000Z

204

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

E-Print Network (OSTI)

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,

Brandt, Adam R.; Farrell, Alexander E.

2008-01-01T23:59:59.000Z

205

An integrated performance model for high temperature gas cooled reactor coated particle fuel  

E-Print Network (OSTI)

The performance of coated fuel particles is essential for the development and deployment of High Temperature Gas Reactor (HTGR) systems for future power generation. Fuel performance modeling is indispensable for understanding ...

Wang, Jing, 1976-

2004-01-01T23:59:59.000Z

206

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

E-Print Network (OSTI)

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 ...

Warburton, Jamie (Jamie L.)

2007-01-01T23:59:59.000Z

207

Evaluation of Operational Model Cyclone Structure Forecasts during Extratropical Transition  

Science Conference Proceedings (OSTI)

Cyclone structure is known to be directly linked to the sensible weather effects produced by the weather system. The extratropical transition (ET) process leads to immense changes in cyclone structure and therefore to changes in the associated ...

Jenni L. Evans; Justin M. Arnott; Francesca Chiaromonte

2006-11-01T23:59:59.000Z

208

Hardening transition in a one-dimensional model for ferrogels  

E-Print Network (OSTI)

We introduce and investigate a coarse-grained model for quasi one-dimensional ferrogels. In our description the magnetic particles are represented by hard spheres with a magnetic dipole moment in their centers. Harmonic springs connecting these spheres mimic the presence of a cross-linked polymer matrix. A special emphasis is put on the coupling of the dipolar orientations to the elastic deformations of the matrix, where a memory effect of the orientations is included. Although the particles are displaced along one spatial direction only, the system already shows rich behavior: as a function of the magnetic dipole moment, we find a phase transition between "soft-elastic" states with finite interparticle separation and finite compressive elastic modulus on the one hand, and "hardened" states with touching particles and therefore diverging compressive elastic modulus on the other hand. Corresponding phase diagrams are derived neglecting thermal fluctuations of the magnetic particles. In addition, we consider a situation in which a spatially homogeneous magnetization is initially imprinted into the material. Depending on the strength of the magneto-mechanical coupling between the dipole orientations and the elastic deformations, the system then relaxes to a uniaxially ferromagnetic, an antiferromagnetic, or a spiral state of magnetization to minimize its energy. One purpose of our work is to provide a largely analytically solvable approach that can provide a benchmark to test future descriptions of higher complexity. From an applied point of view, our results could be exploited, for example, for the construction of novel damping devices of tunable shock absorbance.

M. A. Annunziata; A. M. Menzel; H. Lwen

2013-06-03T23:59:59.000Z

209

Argonne TTRDC - Engines - Multi-Dimensional Modeling - Fuel Spray...  

NLE Websites -- All DOE Office Websites (Extended Search)

primary breakup mechanisms. In a diesel engine, liquid fuel is injected into the combustion chamber near the end of the compression stroke. Following injection, the fuel...

210

Helium Behavior in Oxide Nuclear Fuels: First Principles Modeling  

Science Conference Proceedings (OSTI)

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.

Gryaznov, D.; Rashkeev, Sergey N.; Kotomin, E. A.; Heifets, Eugene; Zhukovskii, Yuri F.

2010-10-01T23:59:59.000Z

211

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

DOE Green Energy (OSTI)

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?

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

2011-12-01T23:59:59.000Z

212

Final Scientific Report : Development of Transition Metal/ Chalcogen Based Cathode Catalysts for PEM Fuel Cells  

DOE Green Energy (OSTI)

The aim of this project was to investigate the potential for using base metal sulfides and selenides as low cost replacements for precious metal catalysts, such as platinum, currently being used in PEM fuel cells. The approach was to deposit thin films of the materials to be evaluated onto inert electrodes and evaluate their activity for the cathode reaction (oxygen reduction) as well as ex-situ structural and compositional characterization. The most active materials identified are CoS2 and the 50:50 solid solution (Co,Ni)S2. However, the OCP of these materials is still considered too low, at 0.83V and 0.89V vs. RHE respectively, for testing in fuel cells. The methods employed here were necessary to compare with the activity of platinum as, when nano-dispersed on carbon supports, the active surface area of these materials is difficult to measure, making comparisons inaccurate. This research adds to the knowledge of potential candidates for platinum replacement in order to reduce the cost of PEM fuel cell technology and promote commercialization. Although the fabrication methods employed here are strictly experimental, methods were also developed to produce nano-dispersed catalysts with similar compositions, structure and activity. Cycling of these catalysts to highly oxidizing potentials resulted in an increase of the open circuit voltage to approach that of platinum, however, it proved difficult to determine why using these dispersed materials. The potential for non-precious, non-metallic, low cost, compound catalysts for PEM fuel cells has been investigated and demonstrated.

Campbell, Stephen, A.

2008-02-29T23:59:59.000Z

213

Considerations for the transition from fuel cell R D to manufacturing  

DOE Green Energy (OSTI)

This paper has discussed some considerations important to making a successful transition from R D to manufacturing. It has described a product commercialization framework and discussed the importance of business analyses, especially product cost analysis, in determining the future potential of an emerging technology. Careful attention to the major elements discussed in this report should help both developers and venture sponsors to reduce the risks inherent in new business ventures.

Cobb, M.S.; Meacham, G.B.K.

1992-01-01T23:59:59.000Z

214

Considerations for the transition from fuel cell R&D to manufacturing  

DOE Green Energy (OSTI)

This paper has discussed some considerations important to making a successful transition from R&D to manufacturing. It has described a product commercialization framework and discussed the importance of business analyses, especially product cost analysis, in determining the future potential of an emerging technology. Careful attention to the major elements discussed in this report should help both developers and venture sponsors to reduce the risks inherent in new business ventures.

Cobb, M.S.; Meacham, G.B.K.

1992-09-01T23:59:59.000Z

215

Modeling for electrical characteristics of solid oxide fuel cell based on fractional calculus  

Science Conference Proceedings (OSTI)

It's vital for the research of electrochemical reaction in solid oxide fuel cell (SOFC) to establish accurate dynamic model of its electrical characteristics. The inherent potential polarization of SOFC is analyzed, and integer order dynamic model is ... Keywords: electrochemical impedance spectroscopy, equivalent circuit, fractional order dynamic model, genetic algorithm, integer order dynamic model, solid oxide fuel cell

HongLiang Cao; Li Xi; ZhongHua Deng; Qin Yi

2009-06-01T23:59:59.000Z

216

Fuel Cell Technologies Office: Wind-to-Hydrogen Cost Modeling and Project  

NLE Websites -- All DOE Office Websites (Extended Search)

Wind-to-Hydrogen Cost Wind-to-Hydrogen Cost Modeling and Project Findings (Text Version) to someone by E-mail Share Fuel Cell Technologies Office: Wind-to-Hydrogen Cost Modeling and Project Findings (Text Version) on Facebook Tweet about Fuel Cell Technologies Office: Wind-to-Hydrogen Cost Modeling and Project Findings (Text Version) on Twitter Bookmark Fuel Cell Technologies Office: Wind-to-Hydrogen Cost Modeling and Project Findings (Text Version) on Google Bookmark Fuel Cell Technologies Office: Wind-to-Hydrogen Cost Modeling and Project Findings (Text Version) on Delicious Rank Fuel Cell Technologies Office: Wind-to-Hydrogen Cost Modeling and Project Findings (Text Version) on Digg Find More places to share Fuel Cell Technologies Office: Wind-to-Hydrogen Cost Modeling and Project Findings (Text Version) on

217

Alternative Liquid Fuels Simulation Model (AltSim).  

DOE Green Energy (OSTI)

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

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

2009-12-01T23:59:59.000Z

218

DEVELOPMENT OF GLASS COMPOSITIONS TO IMMOBILIZE ALKALI, ALKALINE EARTH, LANTHANIDE AND TRANSITION METAL FISSION PRODUCTS FROM NUCLEAR FUEL REPROCESSING  

Science Conference Proceedings (OSTI)

The Advanced Fuel Cycle Initiative (AFCI) waste management strategy revolves around specific treatment of individual or groups of separated waste streams. A goal for the separations processes is to efficiently manage the waste to be dispositioned as high level radioactive waste. The Advanced Fuel Cycle Initiative (AFCI) baseline technology for immobilization of the lanthanide (Ln) and transition metal fission product (TM) wastes is vitrification into a borosilicate glass. A current interest is to evaluate the feasibility of vitrifying combined waste streams to most cost effectively immobilize the wastes resulting from aqueous fuel reprocessing. Studies showed that high waste loadings are achievable for the Ln only (Option 1) stream. Waste loadings in excess of 60 wt % (on a calcined oxide basis) were demonstrated via a lanthanide borosilicate (LaBS) glass. The resulting glasses had excellent relative durability as determined by the Product Consistency Test (PCT). For a combined Ln and TM waste stream glass (Option 2), noble metal solubility was found to limit waste loading. However, the measured PCT normalized elemental releases for this glass were at least an order of magnitude below that of Environmental Assessment (EA) glass. Current efforts to evaluate the feasibility of vitrifying combined Ln, TM, alkali (Cs is the primary radionuclide of concern) and alkaline earth (Sr is the primary radionuclide of concern) wastes (Option 3) have shown that these approaches are feasible. However, waste loading limitations with respect to heat load (Cs/Sr loading), molybdenum solubility and/or noble metal solubility will likely be realized and must be considered in determining the cost effectiveness of these approaches.

Marra, J.; Billings, A.

2009-06-24T23:59:59.000Z

219

Fuels  

NLE Websites -- All DOE Office Websites (Extended Search)

Goals > Fuels Goals > Fuels XMAT for nuclear fuels XMAT is ideally suited to explore all of the radiation processes experienced by nuclear fuels.The high energy, heavy ion accleration capability (e.g., 250 MeV U) can produce bulk damage deep in the sample, achieving neutron type depths (~10 microns), beyond the range of surface sputtering effects. The APS X-rays are well matched to the ion beams, and are able to probe individual grains at similar penetrations depths. Damage rates to 25 displacements per atom per hour (DPA/hr), and doses >2500 DPA can be achieved. MORE» Fuels in LWRs are subjected to ~1 DPA per day High burn-up fuel can experience >2000 DPA. Traditional reactor tests by neutron irradiation require 3 years in a reactor and 1 year cool down. Conventional accelerators (>1 MeV/ion) are limited to <200-400 DPAs, and

220

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

E-Print Network (OSTI)

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 and logistics decisions. This study has two main objectives. The first objective is to develop the use of LIght Detection and Ranging (LIDAR) remote sensing to assess fuel models in East Texas accurately and effectively. More specific goals include: (1) developing LIDAR derived products and the methodology to use them for assessing fuel models; (2) investigating the use of several techniques for data fusion of LIDAR and multispectral imagery for assessing fuel models; (3) investigating the gain in fuels mapping accuracy with LIDAR as opposed to QuickBird imagery alone; and, (4) producing spatially explicit digital fuel maps. The second objective is to model fire behavior using FARSITE (Fire Area Simulator) and to investigate differences in modeling 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 LIDAR data and QuickBird data than with QuickBird imagery alone (76.52%). These two fuel model maps obtained from the first objective were used to see the differences in fire growth with fuel model maps of different accuracies. According to our results, LIDAR derived data provides accurate estimates of surface fuel parameters efficiently and accurately over extensive areas of forests. This study demonstrates the importance of using accurate maps of fuel models derived using new LIDAR remote sensing techniques.

Mutlu, Muge

2006-12-01T23:59:59.000Z

Note: This page contains sample records for the topic "fuels modeling transition" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


221

Modelling of the Uncertainty of Nuclear Fuel Thermal Behaviour Using the URANIE Framework  

Science Conference Proceedings (OSTI)

In the global framework of nuclear fuel behaviour simulation, the response of the models describing the physical phenomena occurring during the irradiation in reactor is mainly conditioned by the confidence in the calculated temperature of the fuel. ... Keywords: uncertainty, thermal behaviour, nuclear fuel, URANIE

Antoine Boulore; Christine Struzik; Fabrice Gaudier

2009-09-01T23:59:59.000Z

222

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

E-Print Network (OSTI)

The Hybrid Solid Oxide Fuel Cell (SOFC) and Gas Turbine (GT) Systems Steady State Modeling Penyarat plants offer high cycle efficiencies. In this work a hybrid solid oxide fuel cell and gas turbine power, Gas turbine, Hybrid, Solid Oxide Fuel Cell hal-00703135,version1-31May2012 Author manuscript

Paris-Sud XI, Université de

223

EIA model documentation: Electricity market module - electricity fuel dispatch  

Science Conference Proceedings (OSTI)

This report documents the National Energy Modeling System Electricity Fuel Dispatch Submodule (EFD), a submodule of the Electricity Market Module (EMM) as it was used for EIA`s Annual Energy Outlook 1997. It replaces previous documentation dated March 1994 and subsequent yearly update revisions. The report catalogues and describes the model assumptions, computational methodology, parameter estimation techniques, model source code, and forecast results generated through the synthesis and scenario development based on these components. This document serves four purposes. First, it is a reference document providing a detailed description of the model for reviewers and potential users of the EFD including energy experts at the Energy Information Administration (EIA), other Federal agencies, state energy agencies, private firms such as utilities and consulting firms, and non-profit groups such as consumer and environmental groups. Second, this report meets the legal requirement of the Energy Information Administration (EIA) to provide adequate documentation in support of its statistical and forecast reports. Third, it facilitates continuity in model development by providing documentation which details model enhancements that were undertaken for AE097 and since the previous documentation. Last, because the major use of the EFD is to develop forecasts, this documentation explains the calculations, major inputs and assumptions which were used to generate the AE097.

NONE

1997-01-01T23:59:59.000Z

224

Genetic programming model of solid oxide fuel cell stack: first results  

Science Conference Proceedings (OSTI)

Models that predict performance are important tools in understanding and designing solid oxide fuel cells (SOFCs). Modelling of SOFC stack-based systems is a powerful approach that can provide useful insights into the nonlinear dynamics of ... Keywords: SOFC stack, genetic programming, modelling, nonlinear dynamics, simulation, solid oxide fuel cells

Uday K. Chakraborty

2008-03-01T23:59:59.000Z

225

Search for Model Year 2001 Vehicles by Fuel or Vehicle Type  

NLE Websites -- All DOE Office Websites (Extended Search)

(Propane) Compressed Natural Gas Vehicles Diesel Vehicles Electric Vehicles Flex-Fuel (E85) Vehicles Hybrid Vehicles Search by Make Search by Model Search by EPA Size Class...

226

Search for Model Year 2004 Vehicles by Fuel or Vehicle Type  

NLE Websites -- All DOE Office Websites (Extended Search)

Vehicles Bifuel (Propane) Compressed Natural Gas Vehicles Diesel Vehicles Flex-Fuel (E85) Vehicles Hybrid Vehicles Search by Make Search by Model Search by EPA Size Class...

227

Search for Model Year 2008 Vehicles by Fuel or Vehicle Type  

NLE Websites -- All DOE Office Websites (Extended Search)

Class... Compressed Natural Gas Vehicles Diesel Vehicles Electric Vehicles Flex-Fuel (E85) Vehicles Hybrid Vehicles Search by Make Search by Model Search by EPA Size Class...

228

Search for Model Year 2003 Vehicles by Fuel or Vehicle Type  

NLE Websites -- All DOE Office Websites (Extended Search)

(Propane) Compressed Natural Gas Vehicles Diesel Vehicles Electric Vehicles Flex-Fuel (E85) Vehicles Hybrid Vehicles Search by Make Search by Model Search by EPA Size Class...

229

Search for Model Year 2002 Vehicles by Fuel or Vehicle Type  

NLE Websites -- All DOE Office Websites (Extended Search)

(Propane) Compressed Natural Gas Vehicles Diesel Vehicles Electric Vehicles Flex-Fuel (E85) Vehicles Hybrid Vehicles Search by Make Search by Model Search by EPA Size Class...

230

Search for Model Year 2000 Vehicles by Fuel or Vehicle Type  

NLE Websites -- All DOE Office Websites (Extended Search)

Vehicles Compressed Natural Gas Vehicles Diesel Vehicles Electric Vehicles Flex-Fuel (E85) Vehicles Hybrid Vehicles Search by Make Search by Model Search by EPA Size Class...

231

Fuel Cell Power Model for CHHP System Economics and Performance Analysis (Presentation)  

DOE Green Energy (OSTI)

Presentation about Fuel Cell Power (FCPower) Model used to analyze the economics and performance of combined heat, hydrogen, and power (CHHP) systems.

Steward, D.

2009-11-16T23:59:59.000Z

232

Search for Model Year 2014 Vehicles by Fuel or Vehicle Type  

NLE Websites -- All DOE Office Websites (Extended Search)

Vehicle Type Model Year: 2014 Select Class... Diesel Vehicles Electric Vehicles Flex-Fuel (E85) Vehicles Hybrid Vehicles Plug-in Hybrid Vehicles...

233

Design of a power management model for a solar/fuel cell hybrid energy system.  

E-Print Network (OSTI)

??This thesis proposes a Power Management Model (PMM) for optimization of several green power generation systems. A Photovoltaic/Fuel cell Hybrid Energy System (PFHES) consisting of (more)

Melendez, Rosana.

2010-01-01T23:59:59.000Z

234

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)  

DOE Green Energy (OSTI)

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).

Eudy, L.; Chandler, K.

2008-05-01T23:59:59.000Z

235

Transition to model-driven engineering: what is revolutionary, what remains the same?  

Science Conference Proceedings (OSTI)

A considerable amount of research has been dedicated to bring the vision of model-driven engineering (MDE) to fruition. However, the practical experiences of organizations that transition to MDE are underreported. This paper presents a case study of ...

Jorge Aranda; Daniela Damian; Arber Borici

2012-09-01T23:59:59.000Z

236

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

E-Print Network (OSTI)

Non-linear inversion modeling for Ultrasound Computer Tomography: transition from soft to hard, the tomographic procedure used is adapted to broadband data acquired in scattering configurations while, Iterative Approximation, Soft Tissues Imaging, Hard Tissues Imaging, Breast, Bones 1. INTRODUCTION

237

Rail + Property Development: A model of sustainable transit finance and urbanism  

E-Print Network (OSTI)

sector investments i n rail transit. References Bernick, M .L. and Spit, T. 1998. Cities on Rail. London: Spon Press.Study of the Integrated Rail-Property Development Model in

Cervero, Robert; Murakami, Jin

2008-01-01T23:59:59.000Z

238

Numerical Simulations and a Conceptual Model of the Stratocumulus to Trade Cumulus Transition  

Science Conference Proceedings (OSTI)

A two-dimensional eddy-resolving model is used to study the transition from the stratocumulus topped boundary layer to the trade cumulus boundary layer. The 10-day simulations use an idealized Lagrangian trajectory representative of summertime ...

Matthew C. Wyant; Christopher S. Bretherton; Hugh A. Rand; David E. Stevens

1997-01-01T23:59:59.000Z

239

Appendix model performance - model documentation renewable fuels module of the National Energy Modeling System  

DOE Green Energy (OSTI)

This appendix discusses performance aspects of the Renewable Fuels Module (RFM). It is intended to present the pattern of response of the RFM to typical changes in its major inputs from other NEMS modules. The overall approach of this document, with the particular statistics presented, is designed to be comparable with similar analyses conducted for all of the modules of NEMS. While not always applicable, the overall approach has been to produce analyses and statistics that are as comparable as possible with model developer`s reports for other NEMS modules. Those areas where the analysis is somewhat limited or constrained are discussed. Because the RFM consists of independent submodules, this appendix is broken down by submodule.

Not Available

1994-09-01T23:59:59.000Z

240

DOE and EPA Release Annual Fuel Economy Guide with 2013 Models | Department  

Energy.gov (U.S. Department of Energy (DOE)) Indexed Site

EPA Release Annual Fuel Economy Guide with 2013 Models EPA Release Annual Fuel Economy Guide with 2013 Models DOE and EPA Release Annual Fuel Economy Guide with 2013 Models December 6, 2012 - 5:00pm Addthis News Media Contact (202) 586-4940 WASHINGTON -- The U.S. Environmental Protection Agency (EPA) and the Department of Energy (DOE) are releasing the 2013 Fuel Economy Guide, giving consumers clear and easy-to-read information to help them choose the most fuel efficient and low greenhouse gas emitting vehicles that meet their needs. The 2013 models include efficient and low-emission vehicles in a variety of classes and sizes, but notable this year is the growing availability of hybrids and the increasing number of electric vehicles. "This Administration has been working to foster a new generation of clean, fuel-efficient American vehicles, and part of that effort is

Note: This page contains sample records for the topic "fuels modeling transition" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


241

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

Science Conference Proceedings (OSTI)

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=510^-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.

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

2011-10-15T23:59:59.000Z

242

Alcohol Transportation Fuels Demonstration Program. Phase 1  

DOE Green Energy (OSTI)

Hawaii has abundant natural energy resources, especially biomass, that could be used to produce alternative fuels for ground transportation and electricity. This report summarizes activities performed during 1988 to June 1991 in the first phase of the Alcohol Transportation Fuels Demonstration Program. The Alcohol Transportation Fuels Demonstration Program was funded initially by the Energy Division of the State of Hawaii`s Department of Business, Economic Development and Tourism, and then by the US Department of Energy. This program was intended to support the transition to an altemative transportation fuel, methanol, by demonstrating the use of methanol fuel and methanol-fueled vehicles, and solving the problems associated with that fuel. Specific objectives include surveying renewable energy resources and ground transportation in Hawaii; installing a model methanol fueling station; demonstrating a methanol-fueled fleet of (spark-ignition engine) vehicles; evaluating modification strategies for methanol-fueled diesel engines and fuel additives; and investigating the transition to methanol fueling. All major objectives of Phase I were met (survey of local renewable resources and ground transportation, installation of methanol refueling station, fleet demonstration, diesel engine modification and additive evaluation, and dissemination of information on alternative fueling), and some specific problems (e.g., relating to methanol fuel contamination during handling and refueling) were identified and solved. Several key issues emerging from Phase I (e.g., methanol corrosion, flame luminosity, and methanol-transition technoeconomics) were recommended as topics for follow-on research in subsequent phases of this program.

Kinoshita, C.M. [ed.

1990-12-31T23:59:59.000Z

243

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

DOE Green Energy (OSTI)

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.

Wang, M.Q.

1996-06-01T23:59:59.000Z

244

Model documentation renewable fuels module of the National Energy Modeling System  

DOE Green Energy (OSTI)

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.

NONE

1997-04-01T23:59:59.000Z

245

Enhanced model and fuzzy strategy of air to fuel ratio control for spark ignition engines  

Science Conference Proceedings (OSTI)

Various mathematical models for the air to fuel ratio and control for spark ignition (SI) engines have been proposed to satisfy technical specifications. This paper reveals an improvement of the mean value model (MVEM) and a simple yet effective nonlinear ... Keywords: Air-fuel ratio, FOPDDT, Fuzzy control, Internal combustion, Nonlinear control

Anurak Jansri; Pitikhate Sooraksa

2012-09-01T23:59:59.000Z

246

Maine Yankee: Making the Transition from an Operating Plant to an Independent Spent Fuel Storage Installation (ISFSI)  

Science Conference Proceedings (OSTI)

The purpose of this paper is to describe the challenges faced by Maine Yankee Atomic Power Company in making the transition from an operating nuclear power plant to an Independent Spent Fuel Storage Installation (ISFSI). Maine Yankee (MY) is a 900-megawatt Combustion Engineering pressurized water reactor whose architect engineer was Stone & Webster. Maine Yankee was put into commercial operation on December 28, 1972. It is located on an 820-acre site, on the shores of the Back River in Wiscasset, Maine about 40 miles northeast of Portland, Maine. During its operating life, it generated about 1.2 billion kilowatts of power, providing 25% of Maine's electric power needs and serving additional customers in New England. Maine Yankee's lifetime capacity factor was about 67% and it employed more than 450 people. The decision was made to shutdown Maine Yankee in August of 1997, based on economic reasons. Once this decision was made planning began on how to accomplish safe and cost effective decommissioning of the plant by 2004 while being responsive to the community and employees.

Norton, W.; McGough, M. S.

2002-02-26T23:59:59.000Z

247

Clean air program: Design guidelines for bus transit systems using alcohol fuel (methanol and ethanol) as an alternative fuel. Final report, July 1995-April 1996  

Science Conference Proceedings (OSTI)

This report provides design guidelines for the safe use of alcohol fuel (Methanol or Ethanol). It is part of a series of individual monographs being published by the FTA providing guidelines for the safe use of Compressed Natural Gas (CNG), Liquefied Natural Gas (LNG), Liquefied Petroleum Gas (LPG) and alcohol fuels (Methanol and Ethanol). Each report in this series describes, for the subject fuel, the important fuel properties, guidelines for the design and operation of bus fueling, storage and maintenance facilities, issues on personnel training and emergency preparedness.

Raj, P.K.; DeMarco, V.R.; Hathaway, W.T.; Kangas, R.

1996-08-01T23:59:59.000Z

248

The FIT 2.0 Model - Fuel-cycle Integration and Tradeoffs  

Science Conference Proceedings (OSTI)

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.

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

2011-06-01T23:59:59.000Z

249

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

E-Print Network (OSTI)

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 ...

Mieloszyk, Alexander James

2012-01-01T23:59:59.000Z

250

Developing custom fire behavior fuel models from ecologically complex fuel structures for upper Atlantic Coastal Plain forests.  

SciTech Connect

Currently geospatial fire behavior analyses are performed with an array of fire behavior modeling systems such as FARSITE, FlamMap, and the Large Fire Simulation System. These systems currently require standard or customized surface fire behavior fuel models as inputs that are often assigned through remote sensing information. The ability to handle hundreds or thousands of measured surface fuelbeds representing the fine scale variation in fire behavior on the landscape is constrained in terms of creating compatible custom fire behavior fuel models. In this study, we demonstrate an objective method for taking ecologically complex fuelbeds from inventory observations and converting those into a set of custom fuel models that can be mapped to the original landscape. We use an original set of 629 fuel inventory plots measured on an 80,000 ha contiguous landscape in the upper Atlantic Coastal Plain of the southeastern United States. From models linking stand conditions to component fuel loads, we impute fuelbeds for over 6000 stands. These imputed fuelbeds were then converted to fire behavior parameters under extreme fuel moisture and wind conditions (97th percentile) using the fuel characteristic classification system (FCCS) to estimate surface fire rate of spread, surface fire flame length, shrub layer reaction intensity (heat load), non-woody layer reaction intensity, woody layer reaction intensity, and litter-lichen-moss layer reaction intensity. We performed hierarchical cluster analysis of the stands based on the values of the fire behavior parameters. The resulting 7 clusters were the basis for the development of 7 custom fire behavior fuel models from the cluster centroids that were calibrated against the FCCS point data for wind and fuel moisture. The latter process resulted in calibration against flame length as it was difficult to obtain a simultaneous calibration against both rate of spread and flame length. The clusters based on FCCS fire behavior parameters represent reasonably identifiable stand conditions, being: (1) pine dominated stands with more litter and down woody debriscomponents than other stands, (2) hardwood and pine stands with no shrubs, (3) hardwood dominated stands with low shrub and high non-woody biomass and high down woody debris, (4) stands with high grass and forb (i.e., non-woody) biomass as well as substantial shrub biomass, (5) stands with both high shrub and litter biomass, (6) pine-mixed hardwood stands with moderate litter biomass and low shrub biomass, and (7) baldcypress-tupelo stands. Models representing these stand clusters generated flame lengths from 0.6 to 2.3 musing a 30 km h{sub 1} wind speed and fireline intensities of 100-1500 kW m{sub 1} that are typical within the range of experience on this landscape. The fuel models ranked 1 < 2 < 7 < 5 < 4 < 3 < 6 in terms of both flame length and fireline intensity. The method allows for ecologically complex data to be utilized in order to create a landscape representative of measured fuel conditions and to create models that interface with geospatial fire models.

Parresol, Bernard, R.; Scott, Joe, H.; Andreu, Anne; Prichard, Susan; Kurth, Laurie

2012-01-01T23:59:59.000Z

251

Liquid-gas phase transition in a two-components isospin lattice gas model for asymmetric nuclear matter  

E-Print Network (OSTI)

A two-components isospin lattice gas model has been employed to study the liquid-gas phase transition for asymmetric nuclear matter. An additional degree of freedom, namely, the asymmetry parameter alpha has been considered carefully for studying the phase transition. We have shown that under the mean field approximation, the liquid-gas phase transition given by this model is of second order. The entropy continues at the phase transition point. The binodal surface is addressed.

Wei Liang Qian; Ru-Keng Su

2002-10-04T23:59:59.000Z

252

Fuel  

E-Print Network (OSTI)

heavy-water-moderated, light-water-moderated and liquid-metal cooled fast breeder reactors fueled with natural or low-enriched uranium and containing thorium mixed with the uranium or in separate target channels. U-232 decays with a 69-year half-life through 1.9-year half-life Th-228 to Tl-208, which emits a 2.6 MeV gamma ray upon decay. We find that pressurized light-water-reactors fueled with LEU-thorium fuel at high burnup (70 MWd/kg) produce U-233 with U-232 contamination levels of about 0.4 percent. At this contamination level, a 5 kg sphere of U-233 would produce a gammaray dose rate of 13 and 38 rem/hr at 1 meter one and ten years after chemical purification respectively. The associated plutonium contains 7.5 percent of the undesirable heat-generating 88-year half-life isotope Pu-238. However, just as it is possible to produce weapon-grade plutonium in low-burnup fuel, it is also practical to use heavy-water reactors to produce U-233 containing only a few ppm of U-232 if the thorium is segregated in target channels and discharged a few times more frequently than the natural-uranium driver fuel. The dose rate from a 5-kg solid sphere of U-233 containing 5 ppm U-232 could be reduced by a further factor of 30, to about 2 mrem/hr, with a close-fitting lead sphere weighing about 100 kg. Thus the proliferation resistance of thorium fuel cycles depends very much upon how they are implemented. The original version of this manuscript was received by Science & Global Security on

Jungmin Kang A

2001-01-01T23:59:59.000Z

253

Ab Initio Enhanced calphad Modeling of Actinide-Rich Nuclear Fuels  

Science Conference Proceedings (OSTI)

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. ? Develop and validate an ab initio approach for predicting actinide alloy energetics for thermodynamic modeling.

Morgan, Dane; Yang, Yong

2013-10-28T23:59:59.000Z

254

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

E-Print Network (OSTI)

or design of improved production cost models. to assess thelearning which lowers production costs, and resourcewhich increases production costs. Each of these modules are

Brandt, Adam R.; Farrell, Alexander E.

2008-01-01T23:59:59.000Z

255

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

SciTech Connect

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.

Cardoni, Jeffrey

2010-11-01T23:59:59.000Z

256

Examining hydrogen transitions.  

DOE Green Energy (OSTI)

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.

Plotkin, S. E.; Energy Systems

2007-03-01T23:59:59.000Z

257

Phase transitions in the two-dimensional ferro- and antiferromagnetic potts models on a triangular lattice  

Science Conference Proceedings (OSTI)

The phase transitions in the two-dimensional ferro- and antiferromagnetic Potts models with q = 3 states of spin on a triangular lattice are studied using cluster algorithms and the classical Monte Carlo method. Systems with linear sizes L = 20-120 are considered. The method of fourth-order Binder cumulants and histogram analysis are used to discover that a second-order phase transition occurs in the ferromagnetic Potts model and a first-order phase transition takes place in the antiferromagnetic Potts model. The static critical indices of heat capacity ({alpha}), magnetic susceptibility ({gamma}), magnetization ({beta}), and correlation radius index ({nu}) are calculated for the ferromagnetic Potts model using the finite-size scaling theory.

Murtazaev, A. K.; Babaev, A. B., E-mail: b_albert78@mail.ru [Russian Academy of Sciences, Institute of Physics, Dagestan Scientific Center (Russian Federation)

2012-12-15T23:59:59.000Z

258

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

E-Print Network (OSTI)

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.

Salman Habib; Emil Mottola; Peter Tinyakov

1996-08-14T23:59:59.000Z

259

Detailed chemical kinetic modeling of diesel combustion with oxygenated fuels  

DOE Green Energy (OSTI)

The influence of oxygenated hydrocarbons as additives to diesel fuels on ignition, NOx emissions and soot production has been examined using a detailed chemical kinetic reaction mechanism. N-heptane was used as a representative diesel fuel, and methanol, ethanol, dimethyl ether and dimethoxymethane were used as oxygenated fuel additives. It was found that addition of oxygenated hydrocarbons reduced NOx levels and reduced the production of soot precursors. When the overall oxygen content in the fuel reached approximately 25% by mass, production of soot precursors fell effectively to zero, in agreement with experimental studies. The kinetic factors responsible for these observations are discussed.

Pitz, W J; Curran, H J; Fisher, E; Glaude, P A; Marinov, N M; Westbrook, C K

1999-10-28T23:59:59.000Z

260

MODELING ASSUMPTIONS FOR THE ADVANCED TEST REACTOR FRESH FUEL SHIPPING CONTAINER  

SciTech Connect

The Advanced Test Reactor Fresh Fuel Shipping Container (ATR FFSC) is currently licensed per 10 CFR 71 to transport a fresh fuel element for either the Advanced Test Reactor, the University of Missouri Research Reactor (MURR), or the Massachusetts Institute of Technology Research Reactor (MITR-II). During the licensing process, the Nuclear Regulatory Commission (NRC) raised a number of issues relating to the criticality analysis, namely (1) lack of a tolerance study on the fuel and packaging, (2) moderation conditions during normal conditions of transport (NCT), (3) treatment of minor hydrogenous packaging materials, and (4) treatment of potential fuel damage under hypothetical accident conditions (HAC). These concerns were adequately addressed by modifying the criticality analysis. A tolerance study was added for both the packaging and fuel elements, full-moderation was included in the NCT models, minor hydrogenous packaging materials were included, and fuel element damage was considered for the MURR and MITR-II fuel types.

Rick J. Migliore

2009-09-01T23:59:59.000Z

Note: This page contains sample records for the topic "fuels modeling transition" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


261

Multifractal regime transition in a modified minority game model  

E-Print Network (OSTI)

The search for more realistic modeling of financial time series reviews several stylized facts of real markets. In this work we focus on the multifractal properties found in price and index signals. Although the usual Minority Game (MG) models do not exhibit multifractality, we study here one of its variants that does. We show that the nonsynchronous MG models in the nonergodic phase is multifractal and in this sense, together with other stylized facts, constitute a better modeling tool. Using the Structure Function (SF) approach we detected the stationary and the scaling range of the time series generated by the MG model and, from the linear (nonlinear) behavior of the SF we identified the fractal (multifractal) regimes. Finally, using the Wavelet Transform Modulus Maxima (WTMM) technique we obtained its multifractal spectrum width for different dynamical regimes.

Crepaldi, Antonio F; Ferreira, Fernando F; Francisco, Gerson

2007-01-01T23:59:59.000Z

262

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

DOE Green Energy (OSTI)

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.

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

2012-01-01T23:59:59.000Z

263

Advancements in the behavioral modeling of fuel elements and related structures  

Science Conference Proceedings (OSTI)

An important aspect of the design and analysis of nuclear reactors is the ability to predict the behavior of fuel elements in the adverse environment of a reactor system. By understanding the thermomechanical behavior of the different materials which constitute a nuclear fuel element, analysis and predictions can be made regarding the integrity and reliability of fuel element designs. The SMiRT conference series, through the division on fuel elements and the post-conference seminars on fuel element modeling, provided technical forums for the international participation in the exchange of knowledge concerning the thermomechanical modeling of fuel elements. This paper discusses the technical advances in the behavioral modeling of fuel elements presented at the SMiRT conference series since its inception in 1971. Progress in the areas of material properties and constitutive relationships, modeling methodologies, and integral modeling approaches was reviewed and is summarized in light of their impact on the thermomechanical modeling of nuclear fuel elements. 34 refs., 5 tabs.

Billone, M.C.; Montgomery, R.O.; Rashid, Y.R.; Head, J.L. (Argonne National Lab., IL (USA); ANATECH Research Corp., San Diego, CA (USA); Royal Naval Coll., Greenwich (UK))

1989-01-01T23:59:59.000Z

264

Application of fracture toughness scaling models to the ductile-to- brittle transition  

SciTech Connect

An experimental investigation of fracture toughness in the ductile-brittle transition range was conducted. A large number of ASTM A533, Grade B steel, bend and tension specimens with varying crack lengths were tested throughout the transition region. Cleavage fracture toughness scaling models were utilized to correct the data for the loss of constraint in short crack specimens and tension geometries. The toughness scaling models were effective in reducing the scatter in the data, but tended to over-correct the results for the short crack bend specimens. A proposed ASTM Test Practice for Fracture Toughness in the Transition Range, which employs a master curve concept, was applied to the results. The proposed master curve over predicted the fracture toughness in the mid-transition and a modified master curve was developed that more accurately modeled the transition behavior of the material. Finally, the modified master curve and the fracture toughness scaling models were combined to predict the as-measured fracture toughness of the short crack bend and the tension specimens. It was shown that when the scaling models over correct the data for loss of constraint, they can also lead to non-conservative estimates of the increase in toughness for low constraint geometries.

Link, R.E. [Naval Surface Warfare Center, Annapolis, MD (United States); Joyce, J.A. [Naval Academy, Annapolis, MD (United States)

1996-01-01T23:59:59.000Z

265

Model for Simulation of Hydride Precipitation in Zr-Based Used Fuel  

Energy.gov (U.S. Department of Energy (DOE)) Indexed Site

for Simulation of Hydride Precipitation in Zr-Based Used Fuel for Simulation of Hydride Precipitation in Zr-Based Used Fuel Claddings: A Status Report on Current Model Capabilities Model for Simulation of Hydride Precipitation in Zr-Based Used Fuel Claddings: A Status Report on Current Model Capabilities The report demonstrates a meso-scale, microstructural evolution model for simulation of zirconium hydride precipitation in the cladding of used fuels during long-term dry-storage. While the Zr-based claddings (regarded as a barrier for containment of radioactive fission products and fuel) are manufactured free of any hydrogen, they absorb hydrogen during service in the reactor. The amount of hydrogen that the cladding picks up is primarily a function of the exact chemistry and microstructure of the claddings and reactor operating conditions, time-temperature history, and

266

EPA and DOE Release Annual Fuel Economy Guide with 2014 Models | Department  

Energy.gov (U.S. Department of Energy (DOE)) Indexed Site

EPA and DOE Release Annual Fuel Economy Guide with 2014 Models EPA and DOE Release Annual Fuel Economy Guide with 2014 Models EPA and DOE Release Annual Fuel Economy Guide with 2014 Models December 3, 2013 - 12:00pm Addthis News Media Contact (202) 586-4940 WASHINGTON - The U.S. Environmental Protection Agency (EPA) and the Department of Energy (DOE) are releasing the 2014 Fuel Economy Guide, providing consumers with a valuable resource to identify and choose the most fuel efficient and low greenhouse gas emitting vehicles that meet their needs. The 2014 models include efficient and low-emission vehicles in a variety of classes and sizes, ensuring a wide variety of choices available for consumers. "For American families, the financial and environmental bottom line are high priorities when shopping for a new vehicle," said Administrator Gina

267

EPA and DOE Release Annual Fuel Economy Guide with 2014 Models | Department  

Energy.gov (U.S. Department of Energy (DOE)) Indexed Site

EPA and DOE Release Annual Fuel Economy Guide with 2014 Models EPA and DOE Release Annual Fuel Economy Guide with 2014 Models EPA and DOE Release Annual Fuel Economy Guide with 2014 Models December 3, 2013 - 12:00pm Addthis News Media Contact (202) 586-4940 WASHINGTON - The U.S. Environmental Protection Agency (EPA) and the Department of Energy (DOE) are releasing the 2014 Fuel Economy Guide, providing consumers with a valuable resource to identify and choose the most fuel efficient and low greenhouse gas emitting vehicles that meet their needs. The 2014 models include efficient and low-emission vehicles in a variety of classes and sizes, ensuring a wide variety of choices available for consumers. "For American families, the financial and environmental bottom line are high priorities when shopping for a new vehicle," said Administrator Gina

268

DOE and EPA Release Annual Fuel Economy Guide with 2013 Models | Department  

Energy.gov (U.S. Department of Energy (DOE)) Indexed Site

DOE and EPA Release Annual Fuel Economy Guide with 2013 Models DOE and EPA Release Annual Fuel Economy Guide with 2013 Models DOE and EPA Release Annual Fuel Economy Guide with 2013 Models December 6, 2012 - 5:00pm Addthis News Media Contact (202) 586-4940 WASHINGTON -- The U.S. Environmental Protection Agency (EPA) and the Department of Energy (DOE) are releasing the 2013 Fuel Economy Guide, giving consumers clear and easy-to-read information to help them choose the most fuel efficient and low greenhouse gas emitting vehicles that meet their needs. The 2013 models include efficient and low-emission vehicles in a variety of classes and sizes, but notable this year is the growing availability of hybrids and the increasing number of electric vehicles. "This Administration has been working to foster a new generation of

269

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  

DOE Green Energy (OSTI)

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.

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

2013-06-01T23:59:59.000Z

270

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

SciTech Connect

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.

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

2011-07-01T23:59:59.000Z

271

Policy iteration based on a learned transition model  

Science Conference Proceedings (OSTI)

This paper investigates a reinforcement learning method that combines learning a model of the environment with least-squares policy iteration (LSPI). The LSPI algorithm learns a linear approximation of the optimal state-action value function; the idea ...

Vivek Ramavajjala; Charles Elkan

2012-09-01T23:59:59.000Z

272

Modeling Convective Transitions in the Presence of Sea lce  

Science Conference Proceedings (OSTI)

A substantial part of the variability in the thermohaline circulation on decadal and longer timescales as found in ocean models is strongly related to the deep-water formation (DWF) process. Many of these studies, however, neglected the role of ...

G. Lenderink; R. J. Haarsma

1996-08-01T23:59:59.000Z

273

Model documentation renewable fuels module of the National Energy Modeling System  

Science Conference Proceedings (OSTI)

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.

NONE

1995-06-01T23:59:59.000Z

274

Model-based diagnosis for proton exchange membrane fuel cells  

Science Conference Proceedings (OSTI)

Proton Exchange Membrane Fuel Cell (PEMFC) systems are more and more presented as a good alternative to current energy converters such as internal combustion engines. They suffer however from insufficient reliability and durability for stationary and ... Keywords: Diagnosis, Elman neural network, Flooding, PEM fuel cell, Water management

N. Yousfi Steiner; D. Candusso; D. Hissel; P. Mooteguy

2010-10-01T23:59:59.000Z

275

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

SciTech Connect

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.

Not Available

1994-04-01T23:59:59.000Z

276

Isospin Lattice-Gas Model and Liquid-Gas Phase Transition in Asymmetric Nuclear Matter  

E-Print Network (OSTI)

An isospin lattice-gas model, which is a spin-1 Ising model, is employed to investigate the liquid-gas phase transition in asymmetric nuclear matter. We consider nuclear matter as a lattice where each lattice site can be either empty or occupied by a proton or a neutron, with a nearest-neighbor interaction among the nucleons. With the Bragg-Williams mean field approximation, we calculate various thermodynamic properties of nuclear matter for different densities and different proton-neutron asymmetry parameter s. Our model exhibits liquidgas phase transition below a critical temperature Tc, and predicts a monotonic decreasing of Tc as the magnitude of s is increased. The dependence of the nuclear matter isotherms on the asymmetry parameter s is discussed. Ray, Shamanna and Kuo / Liquid-gas phase transition in Nuclear matter 2 1.

S. Ray; J. Shamanna; T. T. S. Kuo

2008-01-01T23:59:59.000Z

277

Solid-solid collapse transition in a two dimensional model molecular system  

E-Print Network (OSTI)

Solid-solid collapse transition in open framework structures is ubiquitous in nature. The real difficulty in understanding detailed microscopic aspects of such transitions in molecular systems arises from the interplay between different energy and length scales involved in molecular systems, often mediated through a solvent. In this work we employ Monte Carlo (MC) simulations to study the collapse transition in a model molecular system interacting via both isotropic as well as anisotropic interactions having different length and energy scales. The model we use is known as Mercedes-Benz (MB) which for a specific set of parameters sustains three solid phases: honeycomb, oblique and triangular. In order to study the temperature induced collapse transition, we start with a metastable honeycomb solid and induce transition by heating. High density oblique solid so formed has two characteristic length scales corresponding to isotropic and anisotropic parts of interaction potential. Contrary to the common believe and classical nucleation theory, interestingly, we find linear strip-like nucleating clusters having significantly different order and average coordination number than the bulk stable phase. In the early stage of growth, the cluster grows as linear strip followed by branched and ring-like strips. The geometry of growing cluster is a consequence of the delicate balance between two types of interactions which enables the dominance of stabilizing energy over the destabilizing surface energy. The nuclei of stable oblique phase are wetted by intermediate order particles which minimizes the surface free energy. We observe different pathways for pressure and temperature induced transitions.

Rakesh S. Singh; Biman Bagchi

2013-04-11T23:59:59.000Z

278

Regime Transitions in a Stochastically Forced Double-Gyre Model  

Science Conference Proceedings (OSTI)

A reduced-gravity double-gyre ocean model is used to study the influence of an additive stochastic wind stress component on the regime behavior of the wind-driven circulation. The variance of the stochastic component (spatially coherent white ...

Philip Sura; Klaus Fraedrich; Frank Lunkeit

2001-02-01T23:59:59.000Z

279

Scaling up transit priority modelling using high-throughput computing  

Science Conference Proceedings (OSTI)

The optimization of Road Space Allocation (RSA) from a network perspective is computationally challenging. An analogue to the Network Design Problem (NDP), RSA can be classified NP-hard. In large-scale networks when the number of alternatives increases ... Keywords: genetic algorithm, high-performance computing, high-throughput computing, transport modelling

Mahmoud Mesbah, Majid Sarvi, Jefferson Tan, Fateme Karimirad

2012-01-01T23:59:59.000Z

280

Short communication Electronic circuit model for proton exchange membrane fuel cells ?  

E-Print Network (OSTI)

The proton exchange membrane (PEM) fuel cell is being investigated as an alternate power source for various applications like transportation and emergency power supplies. The paper presents a novel circuit model for a PEM fuel cell that can be used to design and analyze fuel cell power systems. The PSPICE-based model uses bipolar junction transistors (BJTs) and LC elements available in the PSPICE library with some modification. The model includes the phenomena like activation polarization, ohmic polarization, and mass transport effect present in a PEM fuel cell. The static and dynamic characteristics obtained through simulation are compared with experimental results obtained on a commercial fuel cell module. 2004 Elsevier B.V. All rights reserved.

Dachuan Yu; S. Yuvarajan

2004-01-01T23:59:59.000Z

Note: This page contains sample records for the topic "fuels modeling transition" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


281

An electrical modeling and fuzzy logic control of a fuel cell generation system  

SciTech Connect

Fuel cell generation system consists of a stack, a reformer, and converters. The stack generates DC power by electrochemical reaction. For system design and analysis, it is necessary to obtain electrical models. Simplified electrical models of a fuel cell generation system for system control are proposed. Then using the electrical models, system performance of a fuel cell generation system in which power is boosted by step-up choppers is analyzed. A fuzzy controller is designed for improved system performance. Simulation and experimental results confirmed the high performance capability of the designed system.

Kim, Y.H.; Kim, S.S. [Chung-Ang Univ., Seoul (Korea, Republic of). Dept. of Electrical Engineering

1999-06-01T23:59:59.000Z

282

The Hydrogen Infrastructure Transition (HIT) Model and Its Application in Optimizing a 50-year Hydrogen Infrastructure for Urban Beijing  

E-Print Network (OSTI)

a Hydrogen Energy Infrastructure." Annual Review of EnergyZoia (2005). "Hydrogen infrastructure strategic planning0605 The Hydrogen Infrastructure Transition Model (HIT) &

Lin, Zhenhong; Ogden, Joan M; Fan, Yueyue; Sperling, Dan

2006-01-01T23:59:59.000Z

283

The Hydrogen Infrastructure Transition Model (HIT) & Its Application in Optimizing a 50-year Hydrogen Infrastructure for Urban Beijing  

E-Print Network (OSTI)

a Hydrogen Energy Infrastructure." Annual Review of EnergyZoia (2005). "Hydrogen infrastructure strategic planning0605 The Hydrogen Infrastructure Transition Model (HIT) &

Lin, Zhenhong; Ogden, J; Fan, Yueyue; Sperling, Dan

2006-01-01T23:59:59.000Z

284

Fuel Cell Power Model for CHHP System Economics and Performance...  

NLE Websites -- All DOE Office Websites (Extended Search)

heat production (assuming 75% total efficiency for fuel cell) kWhdaycow 4 Finished compost Cubic yardsyear cow 3.32 Electricity required for digester operation kWhcowday 1...

285

Phase transition in the spanning-hyperforest model on complete hypergraphs  

E-Print Network (OSTI)

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.

Bedini, Andrea; Sportiello, Andrea

2009-01-01T23:59:59.000Z

286

Phase transition in the spanning-hyperforest model on complete hypergraphs  

E-Print Network (OSTI)

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.

Andrea Bedini; Sergio Caracciolo; Andrea Sportiello

2009-06-24T23:59:59.000Z

287

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

DOE Green Energy (OSTI)

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.

Wang, M. Q.

1999-10-06T23:59:59.000Z

288

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

SciTech Connect

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)

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

289

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

SciTech Connect

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.

Wang, M.Q.

1996-03-01T23:59:59.000Z

290

Model Year 2012: Alternative Fuel Vehicles and Advanced Technology...  

Alternative Fuels and Advanced Vehicles Data Center (EERE)

Focus Electric sedan ZEV, Tier 2 Bin 1 Auto 105 kW e-motor est. 100 micharge 23 kWh Battery Electric (Li-ion) Ford Transit Connect (Azure Dynamics) Van ZEV, Tier 2 Bin 1 Auto...

291

The Putative Liquid-Liquid Transition is a Liquid-Solid Transition in Atomistic Models of Water, Part II  

E-Print Network (OSTI)

This paper extends our earlier studies of free energy functions of density and crystalline order parameters for models of supercooled water, which allows us to examine the possibility of two distinct metastable liquid phases [J. Chem. Phys. 135, 134503 (2011) and arXiv:1107.0337v2]. Low-temperature reversible free energy surfaces of several different atomistic models are computed: mW water, TIP4P/2005 water, SW silicon and ST2 water, the last of these comparing three different treatments of long-ranged forces. In each case, we show that there is one stable or metastable liquid phase, and there is an ice-like crystal phase. The time scales for crystallization in these systems far exceed those of structural relaxation in the supercooled metastable liquid. We show how this wide separation in time scales produces an illusion of a low-temperature liquid-liquid transition. The phenomenon suggesting metastability of two distinct liquid phases is actually coarsening of the ordered ice-like phase, which we elucidate u...

Limmer, David T

2013-01-01T23:59:59.000Z

292

Modeling Low-Platinum-Loading Effects in Fuel-Cell Catalyst Layers  

E-Print Network (OSTI)

Loading Effects in Fuel-Cell Catalyst Layers Wonseok Yoon*CA 94720, USA The cathode catalyst layer within a proton-with low Pt-loading catalyst layers. Model results

Yoon, Wonseok

2013-01-01T23:59:59.000Z

293

Search for Model Year 2005 Vehicles by Fuel or Vehicle Type  

NLE Websites -- All DOE Office Websites (Extended Search)

Year: 2005 Select Class... Compressed Natural Gas Vehicles Diesel Vehicles Flex-Fuel (E85) Vehicles Hybrid Vehicles Search by Make Search by Model Search by EPA Size Class...

294

Search for Model Year 2013 Vehicles by Fuel or Vehicle Type  

NLE Websites -- All DOE Office Websites (Extended Search)

Class... Compressed Natural Gas Vehicles Diesel Vehicles Electric Vehicles Flex-Fuel (E85) Vehicles Hybrid Vehicles Plug-in Hybrid Vehicles Search by Make Search by Model Search...

295

Search for Model Year 2009 Vehicles by Fuel or Vehicle Type  

NLE Websites -- All DOE Office Websites (Extended Search)

Year: 2009 Select Class... Compressed Natural Gas Vehicles Diesel Vehicles Flex-Fuel (E85) Vehicles Hybrid Vehicles Search by Make Search by Model Search by EPA Size Class...

296

Search for Model Year 2010 Vehicles by Fuel or Vehicle Type  

NLE Websites -- All DOE Office Websites (Extended Search)

Year: 2010 Select Class... Compressed Natural Gas Vehicles Diesel Vehicles Flex-Fuel (E85) Vehicles Hybrid Vehicles Search by Make Search by Model Search by EPA Size Class...

297

Search for Model Year 2012 Vehicles by Fuel or Vehicle Type  

NLE Websites -- All DOE Office Websites (Extended Search)

Class... Compressed Natural Gas Vehicles Diesel Vehicles Electric Vehicles Flex-Fuel (E85) Vehicles Hybrid Vehicles Plug-in Hybrid Vehicles Search by Make Search by Model Search...

298

Search for Model Year 2011 Vehicles by Fuel or Vehicle Type  

NLE Websites -- All DOE Office Websites (Extended Search)

Class... Compressed Natural Gas Vehicles Diesel Vehicles Electric Vehicles Flex-Fuel (E85) Vehicles Hybrid Vehicles Plug-in Hybrid Vehicles Search by Make Search by Model Search...

299

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

DOE Green Energy (OSTI)

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.

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

300

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)

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 ...

Richard, Joshua (Joshua Glenn)

2012-01-01T23:59:59.000Z

Note: This page contains sample records for the topic "fuels modeling transition" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


301

Hydrogen Transition Infrastructure Analysis  

DOE Green Energy (OSTI)

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.

Melendez, M.; Milbrandt, A.

2005-05-01T23:59:59.000Z

302

PNJL model analysis of the Roberge-Weiss transition endpoint at imaginary chemical potential  

E-Print Network (OSTI)

Motivated by lattice QCD studies we investigate the RW transition endpoint at imaginary chemical potential in a two-flavor PNJL model. We focus on the quark-mass dependence of the endpoint using different forms of the Polyakov-loop potential.

Scheffler, David; Wambach, Jochen

2011-01-01T23:59:59.000Z

303

Multiple sea-ice states and abrupt MOC transitions in a general circulation ocean model  

E-Print Network (OSTI)

Multiple sea-ice states and abrupt MOC transitions in a general circulation ocean model Yosef: 25 September 2012 ? Springer-Verlag Berlin Heidelberg 2012 Abstract Sea ice has been suggested, based-called ``sea-ice switch'' mech- anism. An important requirement for this mechanism is that multiple sea-ice

Ashkenazy, Yossi "Yosef"

304

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 , and J. Vovelle December 3, 2010 Contents 1 Introduction 2 2 Phase field equations 3 2.1 Derivation

305

Transition events in butane simulations: Similarities across models Daniel M. Zuckermana)  

E-Print Network (OSTI)

Transition events in butane simulations: Similarities across models Daniel M. Zuckermana of long simulations of all-atom butane using both stochastic and fully solved molecular dynamics, we have behavior in molecular simulations has long been a topic of interest, and butane has been an important test

Zuckerman, Daniel M.

306

EPRI PWR Fuel Cladding Corrosion (PFCC) Model: Volume 2: Corrosion Theory and Rate Equation Development  

Science Conference Proceedings (OSTI)

The EPRI PWR Fuel Cladding Corrosion (PFCC) model has been developed to help utilities manage high burnup fuel cladding corrosion and hydriding issues. The model predicts the peak oxide thickness with 92 percent confidence of being within plus or minus 10 micrometers of the measured value, with a conservative bias of 7 micrometers when the metallurgical variables are well characterized. This volume documents the evolution of the rate equation for predicting Zircaloy cladding corrosion and the database us...

1997-03-04T23:59:59.000Z

307

Modeling the effect of engine assembly mass on engine friction and vehicle fuel economy  

DOE Green Energy (OSTI)

In this paper, an analytical model is developed to estimate the impact of reducing engine assembly mass (the term engine assembly refers to the moving components of the engine system, including crankshafts, valve train, pistons, and connecting rods) on engine friction and vehicle fuel economy. The relative changes in frictional mean effective pressure and fuel economy are proportional to the relative change in assembly mass. These changes increase rapidly as engine speed increases. Based on the model, a 25% reduction in engine assembly mass results in a 2% fuel economy improvement for a typical mid-size passenger car over the EPA Urban and Highway Driving Cycles.

An, Feng [University of California, Riverside, CA (United States); Stodolsky, F. [Argonne National Lab., IL (United States)

1995-06-01T23:59:59.000Z

308

Chemically authentic surrogate mixture model for the thermophysical properties of a coal-derived liquid fuel  

Science Conference Proceedings (OSTI)

We developed a surrogate mixture model to represent the physical properties of a coal-derived liquid fuel using only information obtained from a gas chromatography-mass spectrometry analysis of the fuel and a recently developed 'advanced distillation curve'. We then predicted the density, speed of sound, and viscosity of the fuel and compared them to limited experimental data. The surrogate contains five components (n-propylcyclohexane, trans-decalin, {alpha}-methyldecalin, bicyclohexane, and n-hexadecane), yet comparisons to limited experimental data demonstrate that the model is able to represent the density, sound speed, and viscosity to within 1, 4, and 5%, respectively. 102 refs., 2 figs., 5 tabs.

M.L. Huber; E.W. Lemmon; V. Diky; B.L. Smith; T.J. Bruno [National Institute of Standards and Technology (NIST), Boulder, CO (United States). Physical and Chemical Properties Division

2008-09-15T23:59:59.000Z

309

Final Report for NFE-07-00912: Development of Model Fuels Experimental Engine Data Base & Kinetic Modeling Parameter Sets  

Science Conference Proceedings (OSTI)

The automotive and engine industries are in a period of very rapid change being driven by new emission standards, new types of after treatment, new combustion strategies, the introduction of new fuels, and drive for increased fuel economy and efficiency. The rapid pace of these changes has put more pressure on the need for modeling of engine combustion and performance, in order to shorten product design and introduction cycles. New combustion strategies include homogeneous charge compression ignition (HCCI), partial-premixed combustion compression ignition (PCCI), and dilute low temperature combustion which are being developed for lower emissions and improved fuel economy. New fuels include bio-fuels such as ethanol or bio-diesel, drop-in bio-derived fuels and those derived from new crude oil sources such as gas-to-liquids, coal-to-liquids, oil sands, oil shale, and wet natural gas. Kinetic modeling of the combustion process for these new combustion regimes and fuels is necessary in order to allow modeling and performance assessment for engine design purposes. In this research covered by this CRADA, ORNL developed and supplied experimental data related to engine performance with new fuels and new combustion strategies along with interpretation and analysis of such data and consulting to Reaction Design, Inc. (RD). RD performed additional analysis of this data in order to extract important parameters and to confirm engine and kinetic models. The data generated was generally published to make it available to the engine and automotive design communities and also to the Reaction Design Model Fuels Consortium (MFC).

Bunting, Bruce G [ORNL

2012-10-01T23:59:59.000Z

310

Fuel Performance Analysis Capability in FALCON  

Science Conference Proceedings (OSTI)

The Fuel Analysis and Licensing Code -- New (FALCON) is being developed as a state-of-the-art light water reactor (LWR) fuel performance analysis and modeling code validated to high burnup. Based on a robust finite-element numerical structure, it is capable of analyzing both steady-state and transient fuel behaviors with a seamless transition between the two modes. EPRI plans to release a fully benchmarked and validated beta version of FALCON in 2003.

2002-12-06T23:59:59.000Z

311

The Putative Liquid-Liquid Transition is a Liquid-Solid Transition in Atomistic Models of Water, Part II  

E-Print Network (OSTI)

This paper extends our earlier studies of free energy functions of density and crystalline order parameters for models of supercooled water, which allows us to examine the possibility of two distinct metastable liquid phases [J. Chem. Phys. 135, 134503 (2011) and arXiv:1107.0337v2]. Low-temperature reversible free energy surfaces of several different atomistic models are computed: mW water, TIP4P/2005 water, SW silicon and ST2 water, the last of these comparing three different treatments of long-ranged forces. In each case, we show that there is one stable or metastable liquid phase, and there is an ice-like crystal phase. The time scales for crystallization in these systems far exceed those of structural relaxation in the supercooled metastable liquid. We show how this wide separation in time scales produces an illusion of a low-temperature liquid-liquid transition. The phenomenon suggesting metastability of two distinct liquid phases is actually coarsening of the ordered ice-like phase, which we elucidate using both analytical theory and computer simulation. For the latter, we describe robust methods for computing reversible free energy surfaces, and we consider effects of electrostatic boundary conditions. We show that sensible alterations of models and boundary conditions produce no qualitative changes in low-temperature phase behaviors of these systems, only marginal changes in equations of state. On the other hand, we show that altering sampling time scales can produce large and qualitative nonequilibrium effects. Recent reports of evidence of a liquid-liquid critical point in computer simulations of supercooled water are considered in this light.

David T. Limmer; David Chandler

2013-03-13T23:59:59.000Z

312

Biology and Phase Transition - CECM  

E-Print Network (OSTI)

Dec 24, 2003 ... next up previous. Next: Kaufman and percolation Up: Phase Transition Models in Previous: Phase Transition Models in...

313

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

SciTech Connect

The Intermodal Surface Transportation Efficiency Act of 1991 (ISTEA) established a National Recreational Trails Funding Program and the National Recreational Trails Trust Fund. ISTEA required that certain tax revenue generated from the sales of motor fuel used for off-road recreation be transferred from the Highway Trust Funds to the Trails Trust Fund for recreational trail and facility improvements. In order to apportion the Trails Trust Fund to individual States equitably, the Federal Highway Administration (FHWA) asked the Oak Ridge National Laboratory (ORNL) in 1993 to estimate the amount of motor fuel used for off-road recreation in the State level by different vehicle types. A modification of the methodology developed by ORNL has been used to apportion funds to the States since that time.

Davis, S.C.; Truett, L.F.; Hu, P.S.

1999-07-01T23:59:59.000Z

314

Alternative Fuels Data Center: Heavy-Duty Vehicle and Engine...  

Alternative Fuels and Advanced Vehicles Data Center (EERE)

Transit Connect Application: Van Fuel Types: CNG, Propane Power Source(s): Ford Motor Co. - 2.0L I-4 Additional Description: CNG and propane models are available from contract...

315

Benchmarking of the MIT High Temperature Gas-cooled Reactor TRISO-coated particle fuel performance model  

E-Print Network (OSTI)

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 ...

Stawicki, Michael A

2006-01-01T23:59:59.000Z

316

Drum type fossil fueled power plant control based on fuzzy inverse MIMO model  

Science Conference Proceedings (OSTI)

In this paper, a new fuzzy controller is proposed based on inverse model of boiler-turbine system. Gain scheduling scheme is used to keep feedback rule as close as possible to optimal condition while generating plant Input/Output data. Interaction between ... Keywords: ANFIS, drum type fossil fueled power plant (FFPP), interaction, inverse model control, nonlinear model, robustness

Ali Ghaffari; Mansour Nikkhah Bahrami; Hesam Parsa

2006-06-01T23:59:59.000Z

317

Cathode porous transport irreversibility model for PEM fuel cell design  

Science Conference Proceedings (OSTI)

The influence is studied of slip-irreversibility at the interface between the gas diffusion layer, also referred to here as the porous transport layer, and the catalyst layer of a proton exchange membrane fuel cell (PEMFC). A two-dimensional cathode ... Keywords: catalyst layer, exergy, gas diffusion layer, slip flow irreversibility

E. O. B. Ogedengbe; M. A. Rosen

2009-02-01T23:59:59.000Z

318

Computational Modeling and Optimization of Proton Exchange Membrane Fuel Cells  

E-Print Network (OSTI)

power density (HPD) solid oxide fuel cell (SOFC) is a geometry based on a tubular type SOFC increased power density, but still maintains the beneficial feature of secure sealing for a tubular SOFC. In this paper, the electric performance of a flat-tube HPD SOFC is studied. This paper also investigates

Victoria, University of

319

Modeling-Computer Simulations At Walker-Lane Transitional Zone Region  

Open Energy Info (EERE)

Modeling-Computer Simulations At Walker-Lane Modeling-Computer Simulations At Walker-Lane Transitional Zone Region (Laney, 2005) Exploration Activity Details Location Walker-Lane Transition Zone Geothermal Region Exploration Technique Modeling-Computer Simulations Activity Date Usefulness not indicated DOE-funding Unknown Notes Assembling Crustal Geophysical Data for Geothermal Exploration in the Great Basin, Louie and Coolbaugh. We have compiled velocity information from sources in the literature, results of previous seismic experiments and earthquake-monitoring projects, and data donated from mining, geothermal, and petroleum companies. We also collected (May 2002 and August 2004) two new crustal refraction profiles across western Nevada and the northern and central Sierra. These sections had not been well characterized previously.

320

Monte Carlo calculation of the transition temperature of the anisotropic three-dimensional {ital XY} model  

SciTech Connect

The transition temperature of the spatially anisotropic three-dimensional classical {ital XY} model is calculated by means of Monte Carlo (MC) simulations. In the {ital XY} model the spins are not restricted to the {ital XY} plane, as in the plane rotator model. The results are compared with a self-consistent harmonic approximation calculation (SCHA). In two dimensions the inclusion of effect of vortices pushes down the transition temperature from {ital T}{sub KT}/{ital J}=1.08, given by the standard SCHA to {ital T}{sub KT}/{ital J}=0.70, in good agreement with the MC estimate {ital T}{sub KT}/{ital J}=0.725. {copyright} {ital 1996 The American Physical Society.}

Costa, B.V.; Pereira, A.R.; Pires, A.S. [Departamento de Fisica, Universidade Federal de Minas Gerais, CP 702, Belo Horizonte, 30161970 Minas Gerais (Brazil)] [Departamento de Fisica, Universidade Federal de Minas Gerais, CP 702, Belo Horizonte, 30161970 Minas Gerais (Brazil)

1996-08-01T23:59:59.000Z

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321

Isospin Lattice-Gas Model and Liquid-Gas Phase Transition in Asymmetric Nuclear Matter  

E-Print Network (OSTI)

An isospin lattice-gas model, which is a spin-1 Ising model, is employed to investigate the liquid-gas phase transition in asymmetric nuclear matter. We consider nuclear matter as a lattice where each lattice site can be either empty or occupied by a proton or a neutron, with a nearest-neighbor interaction among the nucleons. With the Bragg-Williams mean field approximation, we calculate various thermodynamic properties of nuclear matter for different densities and different proton-neutron asymmetry parameter $s$. Our model exhibits liquid-gas phase transition below a critical temperature $T_c$, and predicts a monotonic decreasing of $T_c$ as the magnitude of $s$ is increased. The dependence of the nuclear matter isotherms on the asymmetry parameter $s$ is discussed.

S. Ray; J. Shamanna; T. T. S. Kuo

1996-08-13T23:59:59.000Z

322

A Statistical Model of Vehicle Emissions and Fuel Consumption  

E-Print Network (OSTI)

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

Cappiello, Alessandra

2002-09-17T23:59:59.000Z

323

Deconfinement transition in protoneutron stars: Analysis within the Nambu-Jona-Lasinio model  

Science Conference Proceedings (OSTI)

We study the effect of color superconductivity and neutrino trapping on the deconfinement transition of hadronic matter into quark matter in a protoneutron star. To describe the strongly interacting matter a two-phase picture is adopted. For the hadronic phase we use different parametrizations of a nonlinear Walecka model which includes the whole baryon octet. For the quark-matter phase we use an SU(3){sub f} Nambu-Jona-Lasinio effective model which includes color superconductivity. We impose color and flavor conservation during the transition in such a way that just deconfined quark matter is transitorily out of equilibrium with respect to weak interactions. We find that deconfinement is more difficult for small neutrino content and it is easier for lower temperatures although these effects are not too large. In addition they will tend to cancel each other as the protoneutron star cools and deleptonizes, resulting a transition density that is roughly constant along the evolution of the protoneutron star. According to these results the deconfinement transition is favored after substantial cooling and contraction of the protoneutron star.

Lugones, G.; Carmo, T. A. S. do [Universidade Federal do ABC, Centro de Ciencias Naturais e Humanas, Rua Santa Adelia, 166, 09210-170, Santo Andre (Brazil); Grunfeld, A. G. [CONICET, Rivadavia 1917, (1033) Buenos Aires (Argentina); Departmento de Fisica, Comision Nacional de Energia Atomica, (1429) Buenos Aires (Argentina); Department of Physics, Sultan Qaboos University, P.O. Box: 36 Al-Khode 123 Muscat (Oman); Scoccola, N. N. [CONICET, Rivadavia 1917, (1033) Buenos Aires (Argentina); Departmento de Fisica, Comision Nacional de Energia Atomica, (1429) Buenos Aires (Argentina); Universidad Favaloro, Solis 453, (1078) Buenos Aires (Argentina)

2010-04-15T23:59:59.000Z

324

ON THE TRANSITIONAL DISK CLASS: LINKING OBSERVATIONS OF T TAURI STARS AND PHYSICAL DISK MODELS  

Science Conference Proceedings (OSTI)

Two decades ago 'transitional disks' (TDs) described spectral energy distributions (SEDs) of T Tauri stars with small near-IR excesses, but significant mid- and far-IR excesses. Many inferred this indicated dust-free holes in disks possibly cleared by planets. Recently, this term has been applied disparately to objects whose Spitzer SEDs diverge from the expectations for a typical full disk (FD). Here, we use irradiated accretion disk models to fit the SEDs of 15 such disks in NGC 2068 and IC 348. One group has a 'dip' in infrared emission while the others' continuum emission decreases steadily at all wavelengths. We find that the former have an inner disk hole or gap at intermediate radii in the disk and we call these objects 'transitional disks' and 'pre-transitional disks' (PTDs), respectively. For the latter group, we can fit these SEDs with FD models and find that millimeter data are necessary to break the degeneracy between dust settling and disk mass. We suggest that the term 'transitional' only be applied to objects that display evidence for a radical change in the disk's radial structure. Using this definition, we find that TDs and PTDs tend to have lower mass accretion rates than FDs and that TDs have lower accretion rates than PTDs. These reduced accretion rates onto the star could be linked to forming planets. Future observations of TDs and PTDs will allow us to better quantify the signatures of planet formation in young disks.

Espaillat, C.; Andrews, S.; Qi, C.; Wilner, D. [Harvard-Smithsonian Center for Astrophysics, 60 Garden Street, MS-78, Cambridge, MA 02138 (United States); Ingleby, L.; Calvet, N. [Department of Astronomy, University of Michigan, 830 Dennison Building, 500 Church Street, Ann Arbor, MI 48109 (United States); Hernandez, J. [Centro de Investigaciones de Astronomia (CIDA), Merida 5101-A (Venezuela, Bolivarian Republic of); Furlan, E. [National Optical Astronomy Observatory, 950 N. Cherry Ave., Tucson, AZ 85719 (United States); D'Alessio, P. [Centro de Radioastronomia y Astrofisica, Universidad Nacional Autonoma de Mexico, 58089 Morelia, Michoacan (Mexico); Muzerolle, J., E-mail: cespaillat@cfa.harvard.edu, E-mail: sandrews@cfa.harvard.edu, E-mail: cqi@cfa.harvard.edu, E-mail: dwilner@cfa.harvard.edu, E-mail: lingleby@umich.edu, E-mail: ncalvet@umich.edu, E-mail: jesush@cida.ve, E-mail: Elise.Furlan@jpl.nasa.gov, E-mail: p.dalessio@crya.unam.mx, E-mail: muzerol@stsci.edu [Space Telescope Institute, 3700 San Martin Drive, Baltimore, MD 21218 (United States)

2012-03-10T23:59:59.000Z

325

Using System Dynamics to Model the Transition to Biofuels in the United States  

DOE Green Energy (OSTI)

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.

Bush, B.; Duffy, M.; Sandor, D.; Peterson, S.

2008-01-01T23:59:59.000Z

326

A Mathematical Model for Predicting the Life of PEM Fuel Cell Membranes Subjected to Hydration Cycling  

E-Print Network (OSTI)

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...

Burlatsky, S F; O'Neill, J; Atrazhev, V V; Varyukhin, A N; Dmitriev, D V; Erikhman, N S

2013-01-01T23:59:59.000Z

327

Fuels II - Programmaster.org  

Science Conference Proceedings (OSTI)

Mar 5, 2013... hulls laden with transition metals noble to the electrorefining process. ... requiring better fuel performance, the search for different fuel forms is...

328

EIA - The National Energy Modeling System: An Overview 2003-Renewable Fuels  

Gasoline and Diesel Fuel Update (EIA)

Renewable Fuelsl Module Renewable Fuelsl Module The National Energy Modeling System: An Overview 2003 Renewable Fuels Module Figure 11. Renewable Fuels Module Structure. Need help, contact the National Energy Information Center at 202-586-8800. Renewable Fuels Module Table. Need help, contact the National Energy Information Center at 202-586-8800. The renewable fuels module (RFM) represents renewable energy resoures and large–scale technologies used for grid-connected U.S. electricity supply (Figure 11). Since most renewables (biomass, conventional hydroelectricity, geothermal, landfill gas, solar photovoltaics, solar thermal, and wind) are used to generate electricity, the RFM primarily interacts with the electricity market module (EMM). New renewable energy generating capacity is either model–determined or

329

Waste generation process modeling and analysis for fuel reprocessing technologies  

SciTech Connect

Estimates of electric power generation requirements for the next century, even when taking the most conservative tack, indicate that the United States will have to increase its production capacity significantly. If the country determines that nuclear power will not be a significant component of this production capacity, the nuclear industry will have to die, as maintaining a small nuclear component will not be justifiable. However, if nuclear power is to be a significant component, it will probably require some form of reprocessing technology. The once-through fuel cycle is only feasible for a relatively small number of nuclear power plants. If we are maintaining several hundred reactors, the once-through fuel cycle is more expensive and ethically questionable.

Kornreich, D. E. (Drew E.); Koehler, A. C. (Andrew C.); Farman, Richard F.

2002-01-01T23:59:59.000Z

330

A Combustion Model for the TWA 800 Center-Wing Fuel Tank Explosion  

Science Conference Proceedings (OSTI)

In support of the National Transportation Safety Board investigation of the TWA Flight 800 accident, a combined experimental/computational effort was conducted that focused on quarter-scale testing and simulation of the fuel-air explosion in the Boeing 747 center wing fuel tank. This report summarizes the modeling approach used at Sandia National Laboratories. In this approach approximations are introduced that capture the essential physics associated with turbulent flame propagation in multiple compartment fuel tanks. This model efficiently defines the pressure loading conditions during a jet-fuel air explosion in a fuel tank confinement. Modeling calculations compare favorably with a variety of experimental quarter-scale tests conducted in rigid confinement. The modeling describes well the overpressure history in several geometry configurations. Upon demonstrating a reasonable comparison to experimental observations, a parametric study of eight possible ignition sources is then discussed. Model calculations demonstrate that different loading conditions arise as the location of the ignition event is varied. By comparing the inferred damage and calculated impulses to that seen in the recovered tank, it maybe possible to reduce the number of likely sources. A possible extension of this work to better define tank damage includes coupling the combustion model as a pressure loading routine for structural failure analysis.

Baer, M.R.; Gross, R.J.

1998-10-02T23:59:59.000Z

331

Fuel Efficient Diesel Particulate Filter (DPF) Modeling and Development  

DOE Green Energy (OSTI)

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.

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

2010-08-01T23:59:59.000Z

332

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

E-Print Network (OSTI)

and environmentally clean power generation has never been so important. The increasing cost of fossil fuels and more stringent regulations on emissions (particularly CO2 and NOx), together with increasing demand for electricity, make the provision of cost... 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...

Collins, William Tristan

2008-10-14T23:59:59.000Z

333

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

334

THETRIS: A MICRO-SCALE TEMPERATURE AND GAS RELEASE MODEL FOR TRISO FUEL  

SciTech Connect

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.

J. Ortensi; A.M. Ougouag

2011-12-01T23:59:59.000Z

335

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

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.

Greene, David L [ORNL

2007-02-01T23:59:59.000Z

336

Detailed Chemical Kinetic Modeling of Surrogate Fuels for Gasoline and Application to an HCCI Engine  

SciTech Connect

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.

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

337

Quantum Phase Transitions and Heat Capacity in a two-atoms Bose-Hubbard Model  

E-Print Network (OSTI)

We show that a two-atoms Bose-Hubbard model exhibits three different phases in the behavior of thermal entanglement in its parameter space. These phases are demonstrated to be traceable back to the existence of quantum phase transitions in the same system. Significant similarities between the behaviors of thermal entanglement and heat capacity in the parameter space are brought to light thus allowing to interpret the occurrence and the meaning of all these three phases.

Leggio, B; Messina, A

2011-01-01T23:59:59.000Z

338

Nuclear liquid-gas phase transition within the lattice gas model  

E-Print Network (OSTI)

We study the nuclear liquid-gas phase transition on the basis of a two-component lattice gas model. A Metropolis type of sampling method is used to generate microscopic states in the canonical ensemble. The effective equation of state and fragment mass distributions are evaluated in a wide range of temperatures and densities. A definition of the phase coexistence region appropriate for mesoscopic systems is proposed. The caloric curve resulting from different types of freeze-out conditions are presented.

J. Borg; I. N. Mishustin; J. P. Bondorf

1998-09-25T23:59:59.000Z

339

DYNAMIC MODELING STRATEGY FOR FLOW REGIME TRANSITION IN GAS-LIQUID TWO-PHASE FLOWS  

SciTech Connect

In modeling gas-liquid two-phase flows, the concept of flow regime has been used to characterize the global interfacial structure of the flows. Nearly all constitutive relations that provide closures to the interfacial transfers in two-phase flow models, such as the two-fluid model, are often flow regime dependent. Currently, the determination of the flow regimes is primarily based on flow regime maps or transition criteria, which are developed for steady-state, fully-developed flows and widely applied in nuclear reactor system safety analysis codes, such as RELAP5. As two-phase flows are observed to be dynamic in nature (fully-developed two-phase flows generally do not exist in real applications), it is of importance to model the flow regime transition dynamically for more accurate predictions of two-phase flows. The present work aims to develop a dynamic modeling strategy for determining flow regimes in gas-liquid two-phase flows through the introduction of interfacial area transport equations (IATEs) within the framework of a two-fluid model. The IATE is a transport equation that models the interfacial area concentration by considering the creation and destruction of the interfacial area, such as the fluid particle (bubble or liquid droplet) disintegration, boiling and evaporation; and fluid particle coalescence and condensation, respectively. For the flow regimes beyond bubbly flows, a two-group IATE has been proposed, in which bubbles are divided into two groups based on their size and shape (which are correlated), namely small bubbles and large bubbles. A preliminary approach to dynamically identifying the flow regimes is provided, in which discriminators are based on the predicted information, such as the void fraction and interfacial area concentration of small bubble and large bubble groups. This method is expected to be applied to computer codes to improve their predictive capabilities of gas-liquid two-phase flows, in particular for the applications in which flow regime transition occurs.

X. Wang; X. Sun; H. Zhao

2011-09-01T23:59:59.000Z

340

Thermal-hydraulic model of a solid-oxide fuel cell. [17. 5 watts  

DOE Green Energy (OSTI)

A mathematical model has been developed to simulate the electrochemistry and thermal hydraulics in a monolithic solid oxide fuel cell (MSOFC). Dividing a single cell layer into a number of nodes, the model sets up the steady-state heat and mass transfer equations for each node in a cell layer. Based on the average thermal and compositional conditions at each node and a specified cell voltage, the model calculates the Nernst potential and the resultant current, heat generation, and heat removal rates at each node. These calculations yield the temperature and the fuel and oxidant compositions and partial pressure matrices for the entire cell. The simulation also provides related performance data for the fuel cell stack, such as energy efficiency, fuel utilization, and power density. The model can be used to simulate operation with different fuel gases, such as hydrogen, coal gas, and methanol reformate. A mathematical model such as this can be used to examine the effects of changing one or more of the various design variables and to evaluate the effectiveness of fabrication improvements in technology development. In the design phase, the model can be used to determine the size of the stack that will be required for a given power rating and to make design decisions regarding structure-specific parameters, such as the thicknesses of the anode, electrolyte, cathode, and interconnect layers and dimensions of the flow channels in the anode and the cathode. The model can also be helpful to the fuel cell system operator. For example, given a particular stack, the most favorable operating conditions can be determined by determining a priori the effects of altering process variables, such as flow rates and feed conditions. 6 refs., 12 figs., 3 tabs.

Ahmed, S.; Kumar, R.

1990-01-01T23:59:59.000Z

Note: This page contains sample records for the topic "fuels modeling transition" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


341

Fuel Cell Power Model Elucidates Life-Cycle Costs for Fuel Cell-Based Combined Heat, Hydrogen, and Power (CHHP) Production Systems (Fact Sheet)  

Science Conference Proceedings (OSTI)

This fact sheet describes NREL's accomplishments in accurately modeling costs for fuel cell-based combined heat, hydrogen, and power systems. Work was performed by NREL's Hydrogen Technologies and Systems Center.

Not Available

2010-11-01T23:59:59.000Z

342

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  

DOE Green Energy (OSTI)

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.

Gardiner, D. P.; Bardon, M. F.; LaViolette, M.

2010-04-01T23:59:59.000Z

343

Multidisciplinary Modeling, Control, and Optimization of a Solid Oxide Fuel Cell/Gas Turbine Hybrid Power System.  

E-Print Network (OSTI)

??This thesis describes a systematical study, including multidisciplinary modeling, simulation, control, and optimization, of a fuel cell - gas turbine hybrid power system that aims (more)

Abbassi Baharanchi, Atid

2009-01-01T23:59:59.000Z

344

A comparison of geospatially modeled fire behavior and potential application to fire and fuels management for the Savannah River Site.  

SciTech Connect

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.

Kurth, Laurie; Hollingsworth, LaWen; Shea, Dan

2011-12-20T23:59:59.000Z

345

Summary of "Materials Modeling and Simulations for Nuclear Fuels"  

NLE Websites -- All DOE Office Websites (Extended Search)

Summary of "Materials Modeling and Simulations for Nuclear Fuels" Summary of "Materials Modeling and Simulations for Nuclear Fuels" (MMSNF 2013) workshop Director's Welcome Organization Achievements Highlights Fact Sheets, Brochures & Other Documents Multimedia Library About Nuclear Energy Nuclear Reactors Designed by Argonne Argonne's Nuclear Science and Technology Legacy Opportunities within NE Division Visit Argonne Work with Argonne Contact us For Employees Site Map Help Join us on Facebook Follow us on Twitter NE on Flickr Celebrating the 70th Anniversary of Chicago Pile 1 (CP-1) Argonne OutLoud on Nuclear Energy Argonne Energy Showcase 2012 Highlights Bookmark and Share "Materials Modeling and Simulations for Nuclear Fuels" (MMSNF 2013) workshop Workshop Summary Presentation during MMSNF Workshop in Chicago

346

Residential wood burning: Energy modeling and conventional fuel displacement in a national sample  

SciTech Connect

This research studied the natural, built, and behavioral factors predictive of energy consumption for residential space heating with wood or conventional fuels. This study was a secondary analysis of survey data from a nationwide representative sample of 5,682 households collected DOE in the 1984-1985 REC survey. Included were: weather, census division and utility data, interviewer-supplied dwelling measurements and respondent-reported energy-related family behaviors. Linear-regression procedures were used to develop a model that identified key determinants accounting for the variability in wood consumption. A nonlinear-regression model was employed to estimate the amount of conventional fuels used for space heating. The model was also used to estimate the amount of conventional fuels being displaced by wood-heating systems. There was a significant (p {le} .05) linear relationship between the dependent variable, square root of cords burned, various independent variables.

Warsco, K.S.

1988-01-01T23:59:59.000Z

347

Model documentation, Renewable Fuels Module of the National Energy Modeling System  

DOE Green Energy (OSTI)

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.

NONE

1998-01-01T23:59:59.000Z

348

Caloric curve for nuclear liquid-gas phase transition in relativistic mean-field hadronic model  

E-Print Network (OSTI)

The main thermodynamical properties of the first order phase transition of the relativistic mean-field (RMF) hadronic model were explored in the isobaric, the canonical and the grand canonical ensembles on the basis of the method of the thermodynamical potentials and their first derivatives. It was proved that the first order phase transition of the RMF model is the liquid-gas type one associated with the Gibbs free energy $G$. The thermodynamical potential $G$ is the piecewise smooth function and its first order partial derivatives with respect to variables of state are the piecewise continuous functions. We have found that the energy in the caloric curve is discontinuous in the isobaric and the grand canonical ensembles at fixed values of the pressure and the chemical potential, respectively, and it is continuous, i.e. it has no plateau, in the canonical and microcanonical ensembles at fixed values of baryon density, while the baryon density in the isotherms is discontinuous in the isobaric and the canonical ensembles at fixed values of the temperature. The general criterion for the nuclear liquid-gas phase transition in the canonical ensemble was identified.

A. S. Parvan

2011-11-26T23:59:59.000Z

349

Boiler Water Deposition Model for Fossil-Fueled Power Plants  

Science Conference Proceedings (OSTI)

The feasibility of modeling the various processes governing deposition in fossil boilers was assessed in EPRI report 1004931, Boiler Water Deposition Model: Part 1: Feasibility Study, published in 2004. This report presents findings of follow-up activities directed toward the ultimate goal of developing an aggregate model that is applicable to the important deposition phenomena in fossil drum-type boilers.

2007-03-26T23:59:59.000Z

350

Towards CFD Modelling of Critical Heat Flux in Fuel Rod Bundles  

SciTech Connect

The paper describes actual CFD approaches to subcooled boiling and investigates their capability to contribute to fuel assembly design. In a prototype version of the CFD code CFX a wall boiling model is implemented based on a wall heat flux partition algorithm. It can be shown, that the wall boiling model is able, to calculate the cross sectional averaged vapour volume fraction with good agreement to published measurements. The most sensitive parameters of the model are identified. Needs for more detailed experiments are established which are necessary to support further model development. Nevertheless in the paper the model is applied for the investigation of the phenomena inside a hot channel in a fuel assembly. Here the essential parameter is the critical heat flux. Although subcooled boiling represents only a preliminary state toward critical heat flux essential parameters like the swirl, the cross flow between adjacent channels and concentration regions of bubbles can be determined. By calculating the temperature at the rod surface the critical regions can be identified which might later on lead to departure from nucleate boiling and possible damage of the fuel pin. The application of up-to-date CFD with a subcooled boiling model for the simulation of a hot channel enables the comparison and the evaluation of different geometrical designs of the spacer grids of a fuel rod bundle. (authors)

Krepper, Eckhard [Forschungszentrum Rossendorf e.V., Institute of Safety Research, D-01314 Dresden, POB 510119 (Germany); Egorov, Yury [ANSYS Germany GmbH Staudenfeldweg 12, D-83624 Otterfing (Germany); Koncar, Bostjan ['Jozef Stefan' Institute Jamova 39, 1000 Ljubljana (Slovenia)

2006-07-01T23:59:59.000Z

351

Grain Boundary Percolation Modeling of Fission Gas Release in Oxide Fuels  

Science Conference Proceedings (OSTI)

We present a new approach to fission gas release modeling in oxide fuels based on grain boundary network percolation. The method accounts for variability in the bubble growth and coalescence rates on individual grain boundaries, and the resulting effect on macroscopic fission gas release. Two-dimensional representa- tions of fuel pellet microstructures are considered, and the resulting gas release rates are compared with traditional two-stage Booth models, which do not account for long-range percolation on grain boundary net- works. The results show that the requirement of percolation of saturated grain boundaries can considerably reduce the total gas release rates, particularly when gas resolution is considered.

Paul C. Millett; Michael R. Tonks; S. B. Biner

2012-05-01T23:59:59.000Z

352

Modeling Water Management in Polymer-Electrolyte Fuel Cells  

Science Conference Proceedings (OSTI)

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 (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.

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

353

Modeling Water Management in Polymer-Electrolyte Fuel Cells  

DOE Green Energy (OSTI)

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.

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

354

Multi-Scale Modeling of Irradiation Effects on Nuclear Fuel ...  

Science Conference Proceedings (OSTI)

Ab Initio-Based Rate Theory Modeling of Radiation Induced Segregation in ... Benchmarking of Structural Materials Pre-Selected for Advanced Nuclear Reactors.

355

NREL: Vehicles and Fuels Research - Models and Tools  

NLE Websites -- All DOE Office Websites (Extended Search)

momentum, and continuity equations. Models of all the major components-compressor, condenser, expansion device, and evaporator-are included. Available soon for public download....

356

Validation of Models and Simulations of Nuclear Fuels  

Science Conference Proceedings (OSTI)

Symposium, Characterization of Nuclear Reactor Materials and Components with ... Multi-scale theoretical models and computer simulations are often used to...

357

Renewable Fuels Module of the National Energy Modeling System ...  

U.S. Energy Information Administration (EIA)

Model Purpose ... present value of the wind technology over its economi c life and then competes wind technology with fossil and other alternatives in the capacity ...

358

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  

DOE Green Energy (OSTI)

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.

Sefer, N.R.; Russell, J.A.

1980-11-01T23:59:59.000Z

359

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

E-Print Network (OSTI)

Solid Oxide Fuel Cells (SOFCs) are of great interest nowadays. The feature of SOFCs makes them suitable for hybrid systems because they work high operating temperature and when combined with conventional turbine power plants offer high cycle efficiencies. In this work a hybrid solid oxide fuel cell and gas turbine power system model is developed. Two models have been developed based on simple thermodynamic expressions. The simple models are used in the preliminary part of the study and a more realistic based on the performance maps. A comparative study of the simulated configurations, based on an energy analysis is used to perform a parametric study of the overall hybrid system efficiency. Some important observations are made by means of a sensitivity study of the whole cycle for the selected configuration. The results of the selected model were compared to an earlier model from an available literature.

Penyarat Chinda; Pascal Brault

2012-01-01T23:59:59.000Z

360

Two dimensional, two fluid model for sodium boiling in LMFBR fuel assemblies  

Science Conference Proceedings (OSTI)

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.

Granziera, M.R.; Kazimi, M.S.

1980-05-01T23:59:59.000Z

Note: This page contains sample records for the topic "fuels modeling transition" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


361

Summary report on the fuel performance modeling of the AFC-2A, 2B irradiation experiments  

SciTech Connect

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.

Pavel G. Medvedev

2013-09-01T23:59:59.000Z

362

Efficient Bayesian estimation of Markov model transition matrices with given stationary distribution  

E-Print Network (OSTI)

Direct simulation of biomolecular dynamics in thermal equilibrium is challenging due to the metastable nature of conformation dynamics and the computational cost of molecular dynamics. Biased or enhanced sampling methods may improve the convergence of expectation values of equilibrium probabilities and expectation values of stationary quantities significantly. Unfortunately the convergence of dynamic observables such as correlation functions or timescales of conformational transitions relies on direct equilibrium simulations. Markov state models are well suited to describe both, stationary properties and properties of slow dynamical processes of a molecular system, in terms of a transition matrix for a jump process on a suitable discretiza- tion of continuous conformation space. Here, we introduce statistical estimation methods that allow a priori knowledge of equilibrium probabilities to be incorporated into the estimation of dynamical observables. Both, maximum likelihood methods and an improved Monte Carlo sampling method for reversible transition ma- trices with fixed stationary distribution are given. The sampling approach is applied to a toy example as well as to simulations of the MR121-GSGS-W peptide, and is demonstrated to converge much more rapidly than a previous approach in [F. Noe, J. Chem. Phys. 128, 244103 (2008)

Benjamin Trendelkamp-Schroer; Frank Noe

2013-01-10T23:59:59.000Z

363

Experimental and Modeling Study of the Flammability of Fuel Tank Headspace Vapors from High Ethanol Content Fuels  

DOE Green Energy (OSTI)

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.

Gardiner, D.; Bardon, M.; Pucher, G.

2008-10-01T23:59:59.000Z

364

An Economic Analysis of Select Fuel Cycles Using the Steady-State Analysis Model for Advanced Fuel Cycles Schemes (SMAFS)  

Science Conference Proceedings (OSTI)

The U.S. Department of Energy's (DOE) Global Nuclear Energy Partnership (GNEP) is currently considering alternatives to the current U.S. once-through fuel cycle. This report evaluates the relative economics of three alternative fuel cycles to determine those cost components important to overall fuel cycle costs and total generation costs. The analysis determined that the unit cost of nuclear reactors is the most important nuclear generation cost parameter in future fuel cycles. The report also evaluates ...

2007-12-20T23:59:59.000Z

365

DOE Hydrogen and Fuel Cells Program: Macro System Model  

NLE Websites -- All DOE Office Websites (Extended Search)

and Energy Use in Transportation (GREET; versions 1 and 2) H2A Production H2A Delivery Scenario Analysis Model (HDSAM) Hydrogen Demand and Resource Analysis (HyDRA) HyPro...

366

Modeling Water Management in Polymer-Electrolyte Fuel Cells  

E-Print Network (OSTI)

membrane, liquid and ice phases; the movement of ice throughthe membrane, vapor, and ice phases. As in their 1-D model,species, element index, or ice phase = into the control

Weber, Adam; Department of Chemical Engineering, University of California, Berkeley

2008-01-01T23:59:59.000Z

367

Efficient Numerical Methods for an Anisotropic, Nonisothermal, Two-Phase Transport Model of Proton Exchange Membrane Fuel Cell  

Science Conference Proceedings (OSTI)

We carry out model and numerical studies for a three-dimensional, anisotropic, nonisothermal, two-phase steady state transport model of proton exchange membrane fuel cell (PEMFC) in this paper. Besides fully addressing the conservation equations of mass, ... Keywords: Anisotropy, Combined finite element-upwind finite volume, Kirchhoff transformation, Newton's linearization, Nonisothermality, Proton exchange membrane fuel cell (PEMFC), Two-phase transport

Pengtao Sun

2012-04-01T23:59:59.000Z

368

Through-the-electrode model of a proton exchange membrane fuel cell with independently measured parameters  

DOE Green Energy (OSTI)

A one dimensional model for a proton exchange membrane fuel cell was developed which makes use of independently measured parameters for predicting single cell performance. Optimization of catalyst layer formulation and properties are explored. Impact of temperature and cathode pressure upon system performance was investigated.

Weisbrod, K.R.; Grot, S.A.; Vanderborgh, N.E.

1995-05-01T23:59:59.000Z

369

A combustion model for IC engine combustion simulations with multi-component fuels  

Science Conference Proceedings (OSTI)

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)

Ra, Youngchul; Reitz, Rolf D. [Engine Research Center, University of Wisconsin-Madison (United States)

2011-01-15T23:59:59.000Z

370

Control-relevant Modelling and Linear Analysis of Instabilities in Oxy-fuel Combustion  

E-Print Network (OSTI)

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

Foss, Bjarne A.

371

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

E-Print Network (OSTI)

of emissions to global climate change. Although electric cars and buses have been the focus of much of electricModelling and Design Optimization of Low Speed Fuel Cell Hybrid Electric Vehicles by Matthew Blair Supervisors: Dr. Zuomin Dong ABSTRACT Electric vehicles, as an emerging transportation platform, have been

Victoria, University of

372

Through-the-electrode model of a proton exchange membrane fuel cell with independently measured parameters  

DOE Green Energy (OSTI)

A one dimensional model for a proton exchange membrane fuel cell was developed which makes use of independently measured parameters for predicting single cell performance. Optimization of catalyst layer formulation and properties are explored. Impact of temperature and cathode pressure upon system performance is investigated.

Weisbrod, K.R.; Grot, S.A.; Vandergborgh, N.E.

1995-09-01T23:59:59.000Z

373

Optimal Control of the Solid Fuel Ignition Model with H1-Cost  

Science Conference Proceedings (OSTI)

Optimal control problems for the stationary as well as the time-dependent solid fuel ignition model are investigated. Existence of optimal controls is proved, and optimality systems are derived. The analysis is based on a closedness lemma for the exponential ... Keywords: control of exponential nonlinearity, explosion phenomena, optimal control, optimality conditions

Kazufumi Ito; Karl Kunisch

2001-05-01T23:59:59.000Z

374

REACTOR PHYSICS MODELING OF SPENT RESEARCH REACTOR FUEL FOR TECHNICAL NUCLEAR FORENSICS  

SciTech Connect

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.

Nichols, T.; Beals, D.; Sternat, M.

2011-07-18T23:59:59.000Z

375

Boiler Water Deposition Model for Fossil-Fueled Power Plants  

Science Conference Proceedings (OSTI)

Accumulation of internal deposits can adversely affect the performance and availability of boilers and turbines in fossil steam-water cycles. Deposition in drum boilers has been identified as the area of broadest concern to the industry; therefore, an improved understanding of deposition in drum boilers is expected to represent the greatest source of benefits and value to end users. The overall objective of the modeling described here is to develop a comprehensive, integrated model for deposition process...

2011-12-16T23:59:59.000Z

376

Alternative Fuels Data Center: Colorado Leads in Alternative Fuel Use and  

Alternative Fuels and Advanced Vehicles Data Center (EERE)

Colorado Leads in Colorado Leads in Alternative Fuel Use and Public Transit Efficiency to someone by E-mail Share Alternative Fuels Data Center: Colorado Leads in Alternative Fuel Use and Public Transit Efficiency on Facebook Tweet about Alternative Fuels Data Center: Colorado Leads in Alternative Fuel Use and Public Transit Efficiency on Twitter Bookmark Alternative Fuels Data Center: Colorado Leads in Alternative Fuel Use and Public Transit Efficiency on Google Bookmark Alternative Fuels Data Center: Colorado Leads in Alternative Fuel Use and Public Transit Efficiency on Delicious Rank Alternative Fuels Data Center: Colorado Leads in Alternative Fuel Use and Public Transit Efficiency on Digg Find More places to share Alternative Fuels Data Center: Colorado Leads in Alternative Fuel Use and Public Transit Efficiency on

377

A model of the Capital Cost of a natural gas-fired fuel cell based Central Utilities Plant  

DOE Green Energy (OSTI)

This model defines the methods used to estimate the cost associated with acquisition and installation of capital equipment of the fuel cell systems defined by the central utility plant model. The capital cost model estimates the cost of acquiring and installing the fuel cell unit, and all auxiliary equipment such as a boiler, air conditioning, hot water storage, and pumps. The model provides a means to adjust initial cost estimates to consider learning associated with the projected level of production and installation of fuel cell systems. The capital cost estimate is an input to the cost of ownership analysis where it is combined with operating cost and revenue model estimates.

Not Available

1993-06-30T23:59:59.000Z

378

The statistical multifragmentation model for liquid-gas phase transition with a compressible nuclear liquid  

E-Print Network (OSTI)

We propose a new formulation of the statistical multifragmentation model based on the analysis of the virial expansion for a system of the nuclear fragments of all sizes. The developed model not only enables us to account for short-range repulsion, but also to calculate the surface free energy which is induced by the interaction between the fragments. We propose a new parameterization for the liquid phase pressure which allows us to introduce a compressible nuclear liquid into the statistical multifragmentation model. The resulting model is exactly solvable and has no irregular behavior of the isotherms in the mixed phase region that is typical for mean-field models. The general conditions for the 1-st and 2-nd (or higher) order phase transitions are formulated. It is shown that all endpoints of the present model phase diagram are the tricritical points, if the Fisher exponent $\\tau$ is in the range $\\{3}{2} \\le \\tau \\le 2$. The treatment of nuclear liquid compressibility allows us to reduce the tricritical endpoint density of the statistical multifragmentation model to one third of the normal nuclear density. A specific attention is paid to of the fragment size distributions in the region of a negative surface tension at supercritical temperatures.

V. V. Sagun; A. I. Ivanytskyi; K. A. Bugaev; I. N. Mishustin

2013-06-10T23:59:59.000Z

379

Modelling of thermo-mechanical and irradiation behavior of metallic and oxide fuels for sodium fast reactors  

E-Print Network (OSTI)

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 ...

Karahan, Aydin

2009-01-01T23:59:59.000Z

380

System Design Description and Requirements for Modeling the Off-Gas Systems for Fuel Recycling Facilities  

Science Conference Proceedings (OSTI)

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.

Daryl R. Haefner; Jack D. Law; Troy J. Tranter

2010-08-01T23:59:59.000Z

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381

Formulation, Implementation and Validation of a Two-Fluid model in a Fuel Cell CFD Code  

SciTech Connect

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.

Kunal Jain, Vernon Cole, Sanjiv Kumar and N. Vaidya

2008-11-01T23:59:59.000Z

382

Societal lifetime cost of hydrogen fuel cell vehicles  

E-Print Network (OSTI)

Comparative Assessment of Fuel Cell Cars, Massachusettselectric and hydrogen fuel cell vehicles, Journal of PowerTransition to Hydrogen Fuel Cell Vehicles & the Potential

Sun, Yongling; Ogden, J; Delucchi, Mark

2010-01-01T23:59:59.000Z

383

Water Transport in PEM Fuel Cells: Advanced Modeling, Material Selection, Testing, and Design Optimization  

NLE Websites -- All DOE Office Websites (Extended Search)

in PEM Fuel Cells: in PEM Fuel Cells: Advanced Modeling, Material Selection, Testing, and Design Optimization J. Vernon Cole and Ashok Gidwani CFDRC Prepared for: DOE Hydrogen Fuel Cell Kickoff Meeting February 13, 2007 This presentation does not contain any proprietary or confidential information. Background Water Management Issues Arise From: ƒ Generation of water by cathodic reaction ƒ Membrane humidification requirements ƒ Capillary pressure driven transport through porous MEA and GDL materials ƒ Scaling bipolar plate channel dimensions J.H. Nam and M. Kaviany, Int. J. Heat Mass Transfer, 46, pp. 4595-4611 (2003) Relevant Barriers and Targets ƒ Improved Gas Diffusion Layer, Flow Fields, Membrane Electrode Assemblies Needed to Improve Water Management: * Flooding blocks reactant transport

384

WaterTransport in PEM Fuel Cells: Advanced Modeling, Material Selection, Testing and Design Optimization  

Science Conference Proceedings (OSTI)

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.

J. Vernon Cole; Abhra Roy; Ashok Damle; Hari Dahr; Sanjiv Kumar; Kunal Jain; Ned Djilai

2012-10-02T23:59:59.000Z

385

A model and optimization of alternative fuel vehicle fleet composition with triple bottom line concerns .  

E-Print Network (OSTI)

??Alternative fuel types and technologies are increasingly being advocated for transportation needs to ameliorate concerns around energy security, climate change, and fuel cost. Each fuel (more)

Zullo, Johnathon

2012-01-01T23:59:59.000Z

386

Modeling of Solid Oxide Fuel Cell/Gas Turbine Hybrid Systems.  

E-Print Network (OSTI)

?? There is a growing interest in fuel cells for hybrid system. Fuel cells when combined with conventional turbine power plants offer high fuel efficiencies. (more)

Srivastava, Nischal

2006-01-01T23:59:59.000Z

387

Using a Quasipotential Transformation for Modeling Diffusion Media in Polymer-Electrolyte Fuel Cells  

E-Print Network (OSTI)

Proton Exchange Membrane Fuel Cell , Numerical Heat Transferof Polymer Electrolyte Fuel Cells Using a Two-EquationExchange Membrane Fuel Cells 2. Absolute Permeability ,

Weber, Adam Z.

2008-01-01T23:59:59.000Z

388

Improvement of the Post-Blowdown Fuel Channel Analysis Model of Candu for a 35% RIH Break LOCA Without ECC  

SciTech Connect

A CATHENA model for a post-blowdown fuel channel analysis has been improved from an existing one for a Candu-6 reactor, and the analysis for a RIH 35% LBLOCA/LOECC has been performed. The results for the blowdown and post blowdown analyses show that the post blowdown model and its connection with the blowdown analysis model is successfully implemented. Also the 3-D CFD model for the fluid flow and heat transfer in the Candu fuel channel, is being developed for the post blowdown fuel channel heatup experiment CS28-1 using CFX 5.6 and its recent progress is described. (authors)

Rhee, B. W.; Kang, H.S.; Min, B.J. [Korea Atomic Energy Research Institute, P.O. Box 105, Yuseong, Daejeon, 305-600 (Korea, Republic of)

2004-07-01T23:59:59.000Z

389

Effect of finite chemical potential on QGP-Hadron phase transition in a statistical model of fireball formation  

E-Print Network (OSTI)

We study the effect of finite chemical potential for the QGP constituents in the Ramanathan et al. statistical model (Phys.Rev.C70, 027903,2004). While the earlier computations using this model with vanishing chemical potentials indicated a weakly first order phase transition for the system in the vicinity of 170 MeV (Pramana, 68, 757, 2007), the introduction of finite values for the chemical potentials of the constituents makes the transition a smooth roll over of the phases, while allowing fireball formation with radius of a few "fermi" to take place. This seems to be in conformity with the latest consensus on the nature of the QGP-Hadron phase transition. Keywords: Quark Gluon Plasma, Quark Hadron Phase Transition

R. Ramanathan; Agam k. Jha; K. k. Gupta; S. S. Singh

2008-02-18T23:59:59.000Z

390

Radiolysis Model Sensitivity Analysis for a Used Fuel Storage Canister  

SciTech Connect

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.

Wittman, Richard S.

2013-09-20T23:59:59.000Z

391

Industrial fuel choice analysis model. Volume II. Appendices to model documentation  

SciTech Connect

Descriptions, documentation, and other information are included in these appendices dealing with industrial fuel choices: Energy Consumption Data Base; Major Fuel Burning Installation Survey; American Boiler Manufacturers Association Data File; Midrange Energy Forecasting System; Projection Method; Capacity Utilization Rates; Nonboiler Characteristics; Boiler Capital and O and M Cost Data; Nonboiler Capital and O and M Cost Data; Approach to Estimating Energy Impacts of the Coal Conversion Regulatory Program; Index or Acronyms.

1979-01-08T23:59:59.000Z

392

A Mathematical Model for Predicting the Life of PEM Fuel Cell Membranes Subjected to Hydration Cycling  

E-Print Network (OSTI)

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.

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

393

Modeling the oil Transition: A Summary of the Proceedings of the DOE/EPA Workshop on the Economic and Environmental Implications of Global Energy Transitions, February 2007  

NLE Websites -- All DOE Office Websites (Extended Search)

7-014 7-014 Modeling the Oil Transition: A Summary of the Proceedings of the DOE/EPA Workshop on the Economic and Environmental Implications of Global Energy Transitions February 2007 David L. Greene, Editor DOCUMENT AVAILABILITY Reports produced after January 1, 1996, are generally available free via the U.S. Department of Energy (DOE) Information Bridge: Web site: http://www.osti.gov/bridge Reports produced before January 1, 1996, may be purchased by members of the public from the following source: National Technical Information Service 5285 Port Royal Road Springfield, VA 22161 Telephone: 703-605-6000 (1-800-553-6847) TDD: 703-487-4639 Fax: 703-605-6900 E-mail: info@ntis.fedworld.gov Web site: http://www.ntis.gov/support/ordernowabout.htm

394

Uranium Nitride as LWR TRISO Fuel: Thermodynamic Modeling of U-C-N  

SciTech Connect

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.

Besmann, Theodore M [ORNL; Shin, Dongwon [ORNL

2012-01-01T23:59:59.000Z

395

RELAP5 model of the high flux isotope reactor with low enriched fuel thermal flux profiles  

Science Conference Proceedings (OSTI)

The High Flux Isotope Reactor (HFIR) currently uses highly enriched uranium (HEU) fabricated into involute-shaped fuel plates. It is desired that HFIR be able to use low enriched uranium (LEU) fuel while preserving the current performance capability for its diverse missions in material irradiation studies, isotope production, and the use of neutron beam lines for basic research. Preliminary neutronics and depletion simulations of HFIR with LEU fuel have arrived to feasible fuel loadings that maintain the neutronics performance of the reactor. This article illustrates preliminary models developed for the analysis of the thermal-hydraulic characteristics of the LEU core to ensure safe operation of the reactor. The beginning of life (BOL) LEU thermal flux profile has been modeled in RELAP5 to facilitate steady state simulation of the core cooling, and of anticipated and unanticipated transients. Steady state results are presented to validate the new thermal power profile inputs. A power ramp, slow depressurization at the outlet, and flow coast down transients are also evaluated. (authors)

Banfield, J.; Mervin, B.; Hart, S.; Ritchie, J.; Walker, S.; Ruggles, A.; Maldonado, G. I. [Dept. of Nuclear Engineering, Univ. of Tennessee Knoxville, Knoxville, TN 37996-2300 (United States)

2012-07-01T23:59:59.000Z

396

Coupling the Mixed Potential and Radiolysis Models for Used Fuel Degradation  

SciTech Connect

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.

Buck, Edgar C.; Jerden, James L.; Ebert, William L.; Wittman, Richard S.

2013-08-30T23:59:59.000Z

397

Higgs boson resonance parameters and the finite temperature phase transition in a chirally invariant Higgs-Yukawa model  

E-Print Network (OSTI)

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.

John Bulava; Philip Gerhold; Karl Jansen; Jim Kallarackal; Attila Nagy

2011-11-11T23:59:59.000Z

398

MELCOR Model of the Spent Fuel Pool of Fukushima Dai-ichi Unit 4  

DOE Green Energy (OSTI)

Unit 4 of the Fukushima Dai-ichi Nuclear Power Plant suffered a hydrogen explosion at 6:00 am on March 15, 2011, exactly 3.64 days after the earthquake hit the plant and the off-site power was lost. The earthquake occurred on March 11 at 2:47 pm. Since the reactor of this Unit 4 was defueled on November 29, 2010, and all its fuel was stored in the spent fuel pool (SFP4), it was first believed that the explosion was caused by hydrogen generated by the spent fuel, in particular, by the recently discharged core. The hypothetical scenario was: power was lost, cooling to the SFP4 water was lost, pool water heated/boiled, water level decreased, fuel was uncovered, hot Zircaloy reacted with steam, hydrogen was generated and accumulated above the pool, and the explosion occurred. Recent analyses of the radioisotopes present in the water of the SFP4 and underwater video indicated that this scenario did not occur - the fuel in this pool was not damaged and was never uncovered the hydrogen of the explosion was apparently generated in Unit 3 and transported through exhaust ducts that shared the same chimney with Unit 4. This paper will try to answer the following questions: Could that hypothetical scenario in the SFP4 had occurred? Could the spent fuel in the SPF4 generate enough hydrogen to produce the explosion that occurred 3.64 days after the earthquake? Given the magnitude of the explosion, it was estimated that at least 150 kg of hydrogen had to be generated. As part of the investigations of this accident, MELCOR models of the SFP4 were prepared and a series of calculations were completed. The latest version of MELCOR, version 2.1 (Ref. 1), was employed in these calculations. The spent fuel pool option for BWR fuel was selected in MELCOR. The MELCOR model of the SFP4 consists of a total of 1535 fuel assemblies out of which 548 assemblies are from the core defueled on Nov. 29, 2010, 783 assemblies are older assemblies, and 204 are new/fresh assemblies. The total decay heat of the fuel in the pool was, at the time of the accident, 2.284 MWt, of which 1.872 MWt were from the 548 assemblies of the last core discharged and 0.412 MWt were from the older 783 assemblies. These decay heat values were calculated at Oak Ridge National Laboratory using the ORIGEN2.2 code (Ref. 2) - they agree with values reported elsewhere (Ref. 3). The pool dimensions are 9.9 m x 12.2 m x 11.8 m (height), and with the water level at 11.5 m, the pool volume is 1389 m3, of which only 1240 m3 is water, as some volume is taken by the fuel and by the fuel racks. The initial water temperature of the SFP4 was assumed to be 301 K. The fuel racks are made of an aluminum alloy but are modeled in MELCOR with stainless steel and B4C. MELCOR calculations were completed for different initial water levels: 11.5 m (pool almost full, water is only 0.3 m below the top rim), 4.4577 m (top of the racks), 4.2 m, and 4.026 m (top of the active fuel). A calculation was also completed for a rapid loss of water due to a leak at the bottom of the pool, with the fuel rapidly uncovered and oxidized in air. Results of these calculations are shown in the enclosed Table I. The calculation with the initial water level at 11.5 m (full pool) takes 11 days for the water to boil down to the top of the fuel racks, 11.5 days for the fuel to be uncovered, 14.65 days to generate 150 kg of hydrogen and 19 days for the pool to be completely dry. The calculation with the initial water level at 4.4577 m, takes 1.1 days to uncover the fuel and 4.17 days to generate 150 kg of hydrogen. The calculation with the initial water level at 4.02 m takes 3.63 days to generate 150 kg of hydrogen this is exactly the time when the actual explosion occurred in Unit 4. Finally, fuel oxidation in air after the pool drained the water in 20 minutes, generates only 10 kg of hydrogen this is because very little steam is available and Zircaloy (Zr) oxidation with the oxygen of the air does not generate hydrogen. MELCOR calculated water levels and hydrogen generated in the SFP4 as a function of time for initial water le

Carbajo, Juan J [ORNL

2012-01-01T23:59:59.000Z

399

Preliminary Design Report for Modeling of Hydrogen Uptake in Fuel Rod Cladding During Severe Accidents  

DOE Green Energy (OSTI)

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."

Siefken, Larry James

1999-02-01T23:59:59.000Z

400

Development of Novel PEM Membrane and Multiphase CD Modeling of PEM Fuel Cell  

DOE Green Energy (OSTI)

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.

K. J. Berry; Susanta Das

2009-12-30T23:59:59.000Z

Note: This page contains sample records for the topic "fuels modeling transition" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


401

2D Axisymmetric Coupled CFD-kinetics Modeling of a Nonthermal Arc Plasma Torch for Diesel Fuel  

E-Print Network (OSTI)

- kinetics models have been developed to study partial oxidation, steam or autothermal reforming of methane1 Reforming Alexandre Lebouvier, François Cauneau and Laurent Fulcheri* Center for Energy and Processes, MINES-assisted diesel fuel reformer developed for two different applications: (i) onboard H2 production for fuel cell

Paris-Sud XI, Université de

402

Fuel Cell Tri-Generation System Case Study using the H2A Stationary Model  

NLE Websites -- All DOE Office Websites (Extended Search)

Fuel Cell Tri-Generation System Case Fuel Cell Tri-Generation System Case Study using the H2A Stationary Model Darlene Steward/ Mike Penev National Renewable Energy Laboratory Integrated Stationary Power and Transportation Workshop Phoenix, Arizona October 27, 2008 National Renewable Energy Laboratory Innovation for Our Energy Future 2 Introduction Goal: Develop a cost analysis tool that will be flexible and comprehensive enough to realistically analyze a wide variety of potential combined heat and power/hydrogen production scenarios Approach: Rely on the H2A discounted cash flow methodology to develop a new stationary systems model With the help of industry partners, develop and analyze a range of realistic case studies for tri-generation systems. National Renewable Energy Laboratory Innovation for Our Energy Future

403

A Dynamic Two-Phase Flow Model of Proton Exchange Membrane Fuel Cells  

E-Print Network (OSTI)

A dynamic two phase flow model for proton exchange membrane (PEM) fuel cells is presented. The two dimensional along-the-channel model includes the two phase flow of water (gaseous and liquid) in the porous diffusion layers and in the catalyst layers, as well as the transport of the species in the gas phase. Moreover, proton and water transport in the membrane and the oxygen reduction reaction in the cathodic catalyst layer is accounted for. The discretisation of the resulting flow equations is done by a mixed finite element approach. Based on this the transport equations for the species in each phase are discretised by a finite volume scheme. The coupled mixed finite element/finite volume approach gives the spatially resolved water and gas saturation and the species concentrations. In order to describe the charge transport in the fuel cell the Poisson equations for the electrons and protons are solved by using Galerkin finite element schemes.

Karsten Khn; K. Khn; Mario Ohlberger; Jrgen O. Schumacher; C. Ziegler; R. Klfkorn; Karsten Khn Ab; Mario Ohlberger Cd; Jrgen O. Schumacher A; Christoph Ziegler; Robert Klfkorn C

2003-01-01T23:59:59.000Z

404

Pressure-Tuning the Quantum Phase Transition in a Model 2-D Magnet |  

NLE Websites -- All DOE Office Websites (Extended Search)

Reappearing Superconductivity Surprises Scientists Reappearing Superconductivity Surprises Scientists Manipulating Genes with Hidden TALENs A New Discovery Answers an Old Question Peering into the Interfaces of Nanoscale Polymeric Materials Ironing Out the Details of the Earth's Core Science Highlights Archives: 2013 | 2012 | 2011 | 2010 2009 | 2008 | 2007 | 2006 2005 | 2004 | 2003 | 2002 2001 | 2000 | 1998 | Subscribe to APS Science Highlights rss feed Pressure-Tuning the Quantum Phase Transition in a Model 2-D Magnet APRIL 11, 2012 Bookmark and Share Argonne and University of Chicago physicist Sara Haravifard with the instrument on XSD beamline 6-ID-B at the APS used for the high-resolution, high-pressure structural measurements of SCBO at cryogenic temperatures. The fundamental interactions that determine how spins arrange themselves in

405

Well-posedness of an extended model for water-ice phase transitions  

E-Print Network (OSTI)

We propose an improved model explaining the occurrence of high stresses due to the difference in specific volumes during phase transitions between water and ice. The unknowns of the resulting evolution problem are the absolute temperature, the volume increment, and the liquid fraction. The main novelty here consists in including the dependence of the specific heat and of the speed of sound upon the phase. These additional nonlinearities bring new mathematical difficulties which require new estimation techniques based on Moser iteration. We establish the existence of a global solution to the corresponding initial-boundary value problem, as well as lower and upper bounds for the absolute temperature. Assuming constant heat conductivity, we also prove uniqueness and continuous data dependence of the solution.

Krejci, Pavel

2011-01-01T23:59:59.000Z

406

Technology Validation: Fuel Cell Bus Evaluations (Poster)  

DOE Green Energy (OSTI)

Poster discusses hydrogen fuel cell transit bus evaluations conducted for the Hydrogen, Fuel Cells, & Infrastructure Technologies Program (HFCIT). It was presented at the 2006 HFCIT Program Review.

Eudy, L.

2006-05-01T23:59:59.000Z

407

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

SciTech Connect

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.

Powers, J J

2011-11-28T23:59:59.000Z

408

Urban airshed modeling of air quality impacts of alternative transportation fuel use in Los Angeles and Atlanta  

DOE Green Energy (OSTI)

The main objective of NREL in supporting this study is to determine the relative air quality impact of the use of compressed natural gas (CNG) as an alternative transportation fuel when compared to low Reid vapor pressure (RVP) gasoline and reformulated gasoline (RFG). A table lists the criteria, air toxic, and greenhouse gas pollutants for which emissions were estimated for the alternative fuel scenarios. Air quality impacts were then estimated by performing photochemical modeling of the alternative fuel scenarios using the Urban Airshed Model Version 6.21 and the Carbon Bond Mechanism Version IV (CBM-IV) (Geary et al., 1988) Using this model, the authors examined the formation and transport of ozone under alternative fuel strategies for motor vehicle transportation sources for the year 2007. Photochemical modeling was performed for modeling domains in Los Angeles, California, and Atlanta, Georgia.

NONE

1997-12-01T23:59:59.000Z

409

Determination of Basic Structure-Property Relations for Processing and Modeling in Advanced Nuclear Fuel: Microstructure Evolution and Mechanical Properties  

SciTech Connect

The project objective is to study structure-property relations in solid solutions of nitrides and oxides with surrogate elements to simulate the behavior of fuels of inert matrix fuels of interest to the Advanced Fuel Cycle Initiative (AFCI), with emphasis in zirconium-based materials. Work with actual fuels will be carried out in parallel in collaboration with Los Alamos National Laboratory (LANL). Three key aspects will be explored: microstructure characterization through measurement of global texture evolution and local crystallographic variations using Electron Backscattering Diffraction (EBSD); determination of mechanical properties, including fracture toughness, quasi-static compression strength, and hardness, as functions of load and temperature, and, finally, development of structure-property relations to describe mechanical behavior of the fuels based on experimental data. Materials tested will be characterized to identify the mechanisms of deformation and fracture and their relationship to microstructure and its evolution. New aspects of this research are the inclusion of crystallographic information into the evaluation of fuel performance and the incorporation of statistical variations of microstructural variables into simplified models of mechanical behavior of fuels that account explicitly for these variations. The work is expected to provide insight into processing conditions leading to better fuel performance and structural reliability during manufacturing and service, as well as providing a simplified testing model for future fuel production.

Kirk Wheeler; Manuel Parra; Pedro Peralta

2009-03-01T23:59:59.000Z

410

ELECTROCHEMISTRY AND ON-CELL REFORMATION MODELING FOR SOLID OXIDE FUEL CELL STACKS  

SciTech Connect

ABSTRACT Providing adequate and efficient cooling schemes for solid-oxide-fuel-cell (SOFC) stacks continues to be a challenge coincident with the development of larger, more powerful stacks. The endothermic steam-methane reformation reaction can provide cooling and improved system efficiency when performed directly on the electrochemically active anode. Rapid kinetics of the endothermic reaction typically causes a localized temperature depression on the anode near the fuel inlet. It is desirable to extend the endothermic effect over more of the cell area and mitigate the associated differences in temperature on the cell to alleviate subsequent thermal stresses. In this study, modeling tools validated for the prediction of fuel use, on-cell methane reforming, and the distribution of temperature within SOFC stacks, are employed to provide direction for modifying the catalytic activity of anode materials to control the methane conversion rate. Improvements in thermal management that can be achieved through on-cell reforming is predicted and discussed. Two operating scenarios are considered: one in which the methane fuel is fully pre-reformed, and another in which a substantial percentage of the methane is reformed on-cell. For the latter, a range of catalytic activity is considered and the predicted thermal effects on the cell are presented. Simulations of the cell electrochemical and thermal performance with and without on-cell reforming, including structural analyses, show a substantial decrease in thermal stresses for an on-cell reforming case with slowed methane conversion.

Recknagle, Kurtis P.; Jarboe, Daniel T.; Johnson, Kenneth I.; Korolev, Alexander; Khaleel, Mohammad A.; Singh, Prabhakar

2007-01-16T23:59:59.000Z

411

Fluid-Structure Interaction Modeling of High-Aspect Ratio Nuclear Fuel Plates Using COMSOL  

SciTech Connect

The High Flux Isotope Reactor at the Oak Ridge National Lab is in the research stage of converting its fuel from high-enriched uranium to low-enriched uranium. Due to different physical properties of the new fuel and changes to the internal fuel plate design, the current safety basis must be re-evaluated through rigorous computational analyses. One of the areas being explored is the fluid-structure interaction phenomenon due to the interaction of thin fuel plates (50 mils thickness) and the cooling fluid (water). Detailed computational fluid dynamics and fluid-structure interaction simulations have only recently become feasible due to improved numerical algorithms and advancements in computing technology. For many reasons including the already built-in fluid-structure interaction module, COMSOL has been chosen for this complex problem. COMSOL's ability to solve multiphysics problems using a fully-coupled and implicit solution algorithm is crucial in obtaining a stable and accurate solution. Our initial findings show that COMSOL can accurately model such problems due to its ability to closely couple the fluid dynamics and the structural dynamics problems.

Curtis, Franklin G [ORNL] ORNL; Ekici, Kivanc [ORNL] ORNL; Freels, James D [ORNL] ORNL

2013-01-01T23:59:59.000Z

412

Crack Growth in Solid Oxide Fuel Cell Materials: From Discrete to Continuum Damage Modeling  

Science Conference Proceedings (OSTI)

This paper addresses the cracking problem of glass and ceramic materials used in solid oxide fuel cells (SOFCs). Analyses of an internal crack and of an interface crack between dissimilar materials were conducted using a modified boundary layer modeling approach. In this approach, fracture is allowed to occur in a small process window situated at an initial crack tip. Elastic displacement crack-tip fields are prescribed as remote boundary conditions. Crack propagation was first modeled discretely. Next, a continuum damage mechanics (CDM) model for brittle materials was developed to capture damage and crack growth in the process window. In particular, the damage model was applied to a glass-ceramic material that had been developed in-house for sealing purposes. Discrete and continuum damage solutions were then compared. Finally, the CDM model was used to determine the crack propagation direction as a function of a mode mixity measure.

Nguyen, Ba Nghiep; Koeppel, Brian J.; Ahzi, Said; Khaleel, Mohammad A.; Singh, Prabhakar

2006-04-01T23:59:59.000Z

413

Integrated fuel performance and thermal-hydraulic sub-channel models for analysis of sodium fast reactors  

E-Print Network (OSTI)

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 ...

Fricano, Joseph William

2012-01-01T23:59:59.000Z

414

General Circulation Model Calculations of the Direct Radiative Forcing by Anthropogenic Sulfate and Fossil-Fuel Soot Aerosol  

Science Conference Proceedings (OSTI)

A new radiation code within a general circulation model is used to assess the direct solar and thermal radiative forcing by sulfate aerosol of anthropogenic origin and soot aerosol from fossil-fuel burning. The radiative effects of different ...

J. M. Haywood; D. L. Roberts; A. Slingo; J. M. Edwards; K. P. Shine

1997-07-01T23:59:59.000Z

415

A deformation and thermodynamic model for hydride precipitation kinetics in spent fuel cladding  

DOE Green Energy (OSTI)

Hydrogen is contained in the Zircaloy cladding of spent fuel rods from nuclear reactors. All the spent fuel rods placed in a nuclear waste repository will have a temperature history that decreases toward ambient; and as a result, most all of the hydrogen in the Zircaloy will eventually precipitate as zirconium hydride platelets. A model for the density of hydride platelets is a necessary sub-part for predicting Zircaloy cladding failure rate in a nuclear waste repository. A model is developed to describe statistically the hydride platelet density, and the density function includes the orientation as a physical attribute. The model applies concepts from statistical mechanics to derive probable deformation and thermodynamic functionals for cladding material response that depend explicitly on the hydride platelet density function. From this model, hydride precipitation kinetics depend on a thermodynamic potential for hydride density change and on the inner product of a stress tensor and a tensor measure for the incremental volume change due to hydride platelets. The development of a failure response model for Zircaloy cladding exposed to the expected conditions in a nuclear waste repository is supported by the US DOE Yucca Mountain Project. 19 refs., 3 figs.

Stout, R.B.

1989-10-01T23:59:59.000Z

416

Baldrige Program Transition  

Science Conference Proceedings (OSTI)

The Baldrige Performance Excellence Program is transitioning to a Sustainable, Enterprise Model. ... A Vision to Be Among the Best. ...

2013-08-06T23:59:59.000Z

417

Modeling of the reburn process with the use of feedlot biomass as a reburn fuel  

E-Print Network (OSTI)

Coal fired power plants will face many challenges in the near future as new regulations, such as the Clear Sky Act, are being implemented. These regulations impose much stricter limits on NOx emissions and plan to impose limits on mercury emissions from coal fired boilers. At this time no technologies are currently being implemented for control of Hg and this explains the strong interest in this area by the Department of Energy (DOE). Reburn technology is a very promising technology to reduce NOx emissions. Previous experimental research at TAMU reported that Feedlot Biomass (FB) can be a very effective reburn fuel, for reduction of NOx up to 90%-95%; however, little work has been done to model such a process with Feedlot Biomass as reburn fuel. The present work addresses the development of a reburn model to predict NOx and Hg emissions. The model accounts for finite rate of heating of solid fuel particles, mixing with NOx laden hot gases, size distribution, finite gas phase and heterogeneous chemistry, and oxidation and reduction reactions for NOx and Hg. To reduce the computational effort all the reactions, except those involved in mercury oxidation, are modeled using global reactions. Once the model was validated by comparison with experimental findings, extensive parametric studies were performed to evaluate the parameters controlling NOx reduction. From DOE research programs some experimental data regarding the capture of mercury from power plant is available, but currently no experimental data are available for Hg emission with reburn process. This model has shown a very large mercury reduction using biomass as a reburn fuel. The model recommends the following correlations for optimum reduction of NOx: Equivalence Ratio should be above 1.05; mixing time should be below 100ms (especially for biomass); pure air can be used as the carrier gas; the thermal power fraction of the reburner should be between 15% and 25%; residence time should be at least 0.5s and the Surface Mean Diameter (SMD) of the size distribution should be as small as possible, at least below 100 m.

Colmegna, Giacomo

2007-05-01T23:59:59.000Z

418

Characterization of Solid Oxide Fuel Cell Components Using Electromagnetic Model-Based Sensors  

DOE Green Energy (OSTI)

In this Phase I SBIR, the contractor demonstrated a number of capabilities of model-based sensors such as MWM sensors and MWM-Arrays. The key results include (1) porosity/microstructure characterization for anodes, (2) potential for cathode material characterization, (3) stress measurements in nickel and cobalt, and (4) potential for stress measurements in non-magnetic materials with a ferromagnetic layer. In addition, potential applications for manufacturing quality control of nonconductive layers using interdigitated electrode dielectrometers have been identified. The results indicate that JENTEK's MWM technology can be used to significantly reduce solid oxide fuel cell production and operating costs in a number of ways. Preliminary investigations of solid oxide fuel cell health monitoring and scale-up issues to address industry needs have also been performed.

Zilberstein, Vladimir; Craven, Chris; Goldfine, Neil

2004-12-28T23:59:59.000Z

419

Exploratory fuel-cell research: I. Direct-hydrocarbon polymer-electrolyte fuel cell. II. Mathematical modeling of fuel-cell cathodes  

DOE Green Energy (OSTI)

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.

Perry, M.L.; McLarnon, F.R.; Newman, J.S.; Cairns, E.J.

1996-12-01T23:59:59.000Z

420

Waste Classification based on Waste Form Heat Generation in Advanced Nuclear Fuel Cycles Using the Fuel-Cycle Integration and Tradeoffs (FIT) Model  

SciTech Connect

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.

Denia Djokic; Steven J. Piet; Layne F. Pincock; Nick R. Soelberg

2013-02-01T23:59:59.000Z

Note: This page contains sample records for the topic "fuels modeling transition" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


421

Development of fission gas swelling and release models for metallic nuclear fuels  

E-Print Network (OSTI)

Fuel swelling and fission gas generation for fast reactor fuels are of high importance since they are among the main limiting factors in the development of metallic fast reactor fuel. Five new fission gas and swelling ...

Andrews, Nathan Christopher

2012-01-01T23:59:59.000Z

422

Hydrogen and Fuel Cells R&D  

NLE Websites -- All DOE Office Websites (Extended Search)

Liquids --Hydrogen Storage Materials --Hydrogen Storage Systems Modeling and Analysis --Thermochemical Hydrogen * Fuel Cells --Polymer Electrolyte --Modeling & Analysis --Fuel...

423

Physical and chemical comparison of soot in hydrocarbon and biodiesel fuel diffusion flames: A study of model and commercial fuels  

Science Conference Proceedings (OSTI)

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)

Matti Maricq, M. [Research and Advanced Engineering, Ford Motor Company, Dearborn, MI (United States)

2011-01-15T23:59:59.000Z

424

A Two Dimensional Model of a Direct Propane Fuel Cell with an Interdigitated Flow Field .  

E-Print Network (OSTI)

??Increasing environmental concerns as well as diminishing fossil fuel reserves call for a new generation of energy conversion technologies. Fuel cells, which convert the chemical (more)

Khakdaman, Hamidreza

2012-01-01T23:59:59.000Z

425

Evaluation of monsoon seasonality and the tropospheric biennial oscillation transitions in the CMIP models  

E-Print Network (OSTI)

Evaluation of monsoon seasonality and the tropospheric biennial oscillation transitions in the CMIP 26 October 2012. [1] Characteristics of the Indian and Australian summer monsoon systems preferred monsoon transitions between the two regions and from one year to another, that form parts

Ummenhofer, Caroline C.

426

A full factory transient simulation model for the analysis of expected performance in a transition period  

Science Conference Proceedings (OSTI)

Intel's Fab-18 is based in Israel, and has transitioned from producing 0.18-micron logic devices to producing 90nM flash products. During this transition period, the factory has de-ramped in volume of logic while ramping-up flash. AutoSched AP software ...

Moti Klein; Adar Kalir

2006-12-01T23:59:59.000Z

427

THERMAL PERFORMANCE SENSITIVITY STUDIES IN SUPPORT OF MATERIAL MODELING FOR EXTENDED STORAGE OF USED NUCLEAR FUEL  

SciTech Connect

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.

Cuta, Judith M.; Suffield, Sarah R.; Fort, James A.; Adkins, Harold E.

2013-08-15T23:59:59.000Z

428

Fuel Guide Economy  

NLE Websites -- All DOE Office Websites (Extended Search)

1 1 MODEL YEAR 2000 FUEL ECONOMY LEADERS IN POPULAR VEHICLE CLASSES Listed below are the vehicles with the highest fuel economy for the most popular classes, including both automatic and manual transmissions and gasoline and diesel vehicles. Please be aware that many of these vehicles come in a range of engine sizes and trim lines, resulting in different fuel economy values. Check the fuel economy guide or the fuel economy sticker on new vehicles to find the values for a particular version of a vehicle. CONTENTS MODEL YEAR 2000 FUEL ECONOMY LEADERS ................. 1 HOW TO USE THIS GUIDE ..................................................... 2 FUEL ECONOMY AND YOUR ANNUAL FUEL COSTS .......... 3 WHY FUEL ECONOMY IS IMPORTANT .................................

429

A Novel Phase of Compressed Bilayers That Models the Prestalk Transition  

Science Conference Proceedings (OSTI)

The force model of protein-mediated membrane fusion hypothesizes that fusion is driven by mechanical forces exerted on the membranes, but many details are unknown. Here, we investigated by x-ray diffraction the consequence of applying compressive force on a stack of membranes against the hydration barrier. We found that as the osmotic pressure increased, the lamellar phase transformed first to a new phase of tetragonal lattice (T-phase) over a narrow range of relative humidity, and then to a phase of rhombohedral lattice. The unit cell structure changed from parallel bilayers to a bent configuration with a point contact between adjacent bilayers and then to the stalk hemifusion configuration. The T-phase is discussed as a possible transition state in the membrane merging pathway of fusion. We estimate the work required to form the T-phase and the subsequent hemifusion-stalk-resembling R-phase. The work for the formation of a stalk is compatible with the energy estimated to be released by several SNARE complexes.

Qian, Shuo [ORNL

2012-01-01T23:59:59.000Z

430

Hydrogen Fuel Cell Vehicles  

E-Print Network (OSTI)

Operation of a Solid Polymer Fuel Cell: A Parametric Model,"1991). G. Bronoel, "Hydrogen-Air Fuel Cells Without PreciousG. Abens, "Development of a Fuel Cell Power Source for Bus,"

Delucchi, Mark

1992-01-01T23:59:59.000Z

431

Detailed chemical kinetic models for large n-alkanes and iso-alkanes found in conventional and F-T diesel fuels  

DOE Green Energy (OSTI)

Detailed chemical kinetic models are needed to simulate the combustion of current and future transportation fuels. These models should represent the various chemical classes in these fuels. Conventional diesel fuels are composed of n-alkanes, iso-alkanes, cycloalkanes and aromatics (Farrell et al. 2007). For future fuels, there is a renewed interest in Fischer-Tropsch (F-T) processes which can be used to synthesize diesel and other transportation fuels from biomass, coal and natural gas. F-T diesel fuels are expected to be similar to F-T jet fuels which are commonly comprised of iso-alkanes with some n-alkanes (Smith and Bruno, 2008). Thus, n-alkanes and iso-alkanes are common chemical classes in these conventional and future fuels. This paper reports on the development of chemical kinetic models of large n-alkanes and iso-alkanes to represent these chemical classes in conventional and future fuels. Two large iso-alkanes are 2,2,4,4,6,8,8-heptamethylnonane, which is a primary reference fuel for diesel, and isooctane, a primary reference fuel for gasoline. Other iso-alkanes are branched alkanes with a single methyl side chain, typical of most F-T fuels. The chemical kinetic models are then used to predict the effect of these fuel components on ignition characteristics under conditions found in internal combustion engines.

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

2008-12-15T23:59:59.000Z

432

System modelling to support accelerated fuel transfer rate at EBR-II  

Science Conference Proceedings (OSTI)

The Experimental Breeder Reactor-II (EBR-II) ia a 62.5 MW(th) liquid metal reactor operated by Argonne National Laboratory for The United States Department of Energy. The reactor is located near Idaho Falls, Idaho at the Argonne-West site (ANL-W). Full power operation was achieved in 1964,- the reactor operated continuously since that time until October 1994 in a variety of configurations depending on the programmatic mission. A three year program was initiated in October, 1993 to replace the 330 depleted uranium blanket subassemblies (S/As) with stainless steel reflectors. It was intended to operate the reactor during the three year blanket unloading program, followed by about a half year of driver fuel unloading. However, in the summer of 1994, Congress dictacted that EBR-II be shut down October 1, and complete defueling without operation. To assist in the planning for resources needed for this defueling campaign, a mathematical model of the fuel handling sequence was developed utilizing the appropriate reliability factors and inherent mm constraints of each stage of the process. The model allows predictions of transfer rates under different scenarios. Additionally, it has facilitated planning of maintenance activities, as well as optimization of resources regarding manpower and modification effort. The model and its application is described in this paper.

Imel, G.R.; Houshyar, A.; Planchon, H.P.; Cutforth, D.C.

1995-06-01T23:59:59.000Z

433

Using a Quasipotential Transformation for Modeling Diffusion Media inPolymer-Electrolyte Fuel Cells  

SciTech Connect

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.

Weber, Adam Z.; Newman, John

2008-08-29T23:59:59.000Z

434

SOLID OXIDE FUEL CELL MANUFACTURING COST MODEL: SIMULATING RELATIONSHIPS BETWEEN PERFORMANCE, MANUFACTURING, AND COST OF PRODUCTION  

DOE Green Energy (OSTI)

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.

Eric J. Carlson; Yong Yang; Chandler Fulton

2004-04-20T23:59:59.000Z

435

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)

E STIMATES OF EMISSIONS FACTORS FOR ALCOHOL FUEL PRODUCTIONOF EMISSIONS FACTORS FOR ALCOHOL FUEL PRODUCTION PLANTS A.

Delucchi, Mark

2003-01-01T23:59:59.000Z

436

Interplay between electronic structure and catalytic activity in transition metal oxide model system  

E-Print Network (OSTI)

The efficiency of many energy storage and conversion technologies, such as hydrogen fuel cells, rechargeable metal-air batteries, and hydrogen production from water splitting, is limited by the slow kinetics of the oxygen ...

Suntivich, Jin

2012-01-01T23:59:59.000Z

437

Secondary fuel delivery system  

SciTech Connect

A secondary fuel delivery system for delivering a secondary stream of fuel and/or diluent to a secondary combustion zone located in the transition piece of a combustion engine, downstream of the engine primary combustion region is disclosed. The system includes a manifold formed integral to, and surrounding a portion of, the transition piece, a manifold inlet port, and a collection of injection nozzles. A flowsleeve augments fuel/diluent flow velocity and improves the system cooling effectiveness. Passive cooling elements, including effusion cooling holes located within the transition boundary and thermal-stress-dissipating gaps that resist thermal stress accumulation, provide supplemental heat dissipation in key areas. The system delivers a secondary fuel/diluent mixture to a secondary combustion zone located along the length of the transition piece, while reducing the impact of elevated vibration levels found within the transition piece and avoiding the heat dissipation difficulties often associated with traditional vibration reduction methods.

Parker, David M. (Oviedo, FL); Cai, Weidong (Oviedo, FL); Garan, Daniel W. (Orlando, FL); Harris, Arthur J. (Orlando, FL)

2010-02-23T23:59:59.000Z

438

Detailed chemical kinetic models for large n-alkanes and iso-alkanes found in conventional and F-T diesel fuels  

SciTech Connect

n-Hexadecane and 2,2,4,4,6,8,8-heptamethylnonane represent the primary reference fuels for diesel that are used to determine cetane number, a measure of the ignition property of diesel fuel. With the development of chemical kinetics models for both primary reference fuels, a new capability is now available to model diesel fuel ignition. Additionally, we have developed chemical kinetic models for a whole series of large n-alkanes and a large iso-alkane to represent these chemical classes in fuel surrogates for conventional and future fuels. These chemical kinetic models are used to predict the effect of the aforementioned fuel components on ignition characteristics under conditions found in internal combustion engines.

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

2009-03-09T23:59:59.000Z

439

Improved modeling of the Rossiter-McLaughlin effect for transiting exoplanets  

E-Print Network (OSTI)

We present an improved formula for the anomalous radial velocity of the star during planetary transits due to the Rossiter-McLaughlin (RM) effect. The improvement comes from a more realistic description of the stellar ...

Hirano, Teruyuki

440

Control Strategies For Transit Priority  

E-Print Network (OSTI)

Light Rail Transit," Transportation Research Record, No.Rail Signal Control Strategies by Combining Transit and Traffic Simulation Models," Transportation Research

Skabardonis, Alexander

1998-01-01T23:59:59.000Z

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