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dc.contributor.authorGurski, Stephen Danielen_US
dc.date.accessioned2014-03-14T20:50:22Z
dc.date.available2014-03-14T20:50:22Z
dc.date.issued2002-12-12en_US
dc.identifier.otheretd-12192002-162600en_US
dc.identifier.urihttp://hdl.handle.net/10919/36290
dc.description.abstractIn recent years government, academia and industry have been pursuing fuel cell technology as an alternative to current power generating technologies. The automotive industry has targeted fuel cell technology as a potential alternative to internal combustion engines. The goal of this research is to understand and quantify the impact and effects of low temperature operation has on the performance and efficiency of vehicle fuel cell systems through modeling. More specifically, this work addresses issues of the initial thermal transient known to the automotive community as "cold-start" effects. Cold-start effects play a significant role in power limitations in a fuel cell vehicle, and may require hybridization (batteries) to supplement available power. A fuel cell system model developed as part of this work allows users to define the basic thermal fluid relationships in a fuel cell system. The model can be used as a stand-alone version or as part of a complex fuel cell vehicle model. Fuel cells are being considered for transportation primarily because they have the ability to increase vehicle energy efficiency and significantly reduce or eliminate tailpipe emissions. A proton exchange membrane fuel cell is an electrochemical device for which the operational characteristics depend heavily upon temperature. Thus, it is important to know how the thermal design of the system affects the performance of a fuel cell, which governs the efficiency and performance of the system. This work revealed that the impact on efficiency of a cold-start yielded a 5 % increase in fuel use over a regulated drive cycle for the converted sport utility vehicle. The performance of the fuel cell vehicle also suffered due to operation at low temperatures. Operation of the fuel cell at 20 C yielded only 50% of the available power to the vehicle system.en_US
dc.publisherVirginia Techen_US
dc.relation.haspartsgurski@vt.edu_thesis.pdf.pdfen_US
dc.rightsI hereby certify that, if appropriate, I have obtained and attached hereto a written permission statement from the owner(s) of each third party copyrighted matter to be included in my thesis, dissertation, or project report, allowing distribution as specified below. I certify that the version I submitted is the same as that approved by my advisory committee. I hereby grant to Virginia Tech or its agents the non-exclusive license to archive and make accessible, under the conditions specified below, my thesis, dissertation, or project report in whole or in part in all forms of media, now or hereafter known. I retain all other ownership rights to the copyright of the thesis, dissertation or project report. I also retain the right to use in future works (such as articles or books) all or part of this thesis, dissertation, or project report.en_US
dc.subjectFuel Cellen_US
dc.subjectTransienten_US
dc.subjectHybrid Vehiclesen_US
dc.subjectModelingen_US
dc.subjectCold-starten_US
dc.titleCold-start effects on performance and efficiency for vehicle fuel cell systemsen_US
dc.typeThesisen_US
dc.contributor.departmentMechanical Engineeringen_US
dc.description.degreeMaster of Scienceen_US
thesis.degree.nameMaster of Scienceen_US
thesis.degree.levelmastersen_US
thesis.degree.grantorVirginia Polytechnic Institute and State Universityen_US
thesis.degree.disciplineMechanical Engineeringen_US
dc.contributor.committeechairNelson, Douglas J.en_US
dc.contributor.committeemembervon Spakovsky, Michael R.en_US
dc.contributor.committeememberEllis, Michael W.en_US
dc.identifier.sourceurlhttp://scholar.lib.vt.edu/theses/available/etd-12192002-162600/en_US
dc.date.sdate2002-12-19en_US
dc.date.rdate2003-12-23
dc.date.adate2002-12-23en_US


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