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dc.contributor.authorCastagne, David
dc.contributor.otherQueen's University (Kingston, Ont.). Theses (Queen's University (Kingston, Ont.))en
dc.date2008-01-09 15:23:08.463en
dc.date2008-09-19 12:14:29.079en
dc.date.accessioned2008-09-19T19:14:12Z
dc.date.available2008-09-19T19:14:12Z
dc.date.issued2008-09-19T19:14:12Z
dc.identifier.urihttp://hdl.handle.net/1974/1448
dc.descriptionThesis (Master, Chemical Engineering) -- Queen's University, 2008-09-19 12:14:29.079en
dc.description.abstractMathematical modeling helps researchers to understand the transport and kinetic phenomena within fuel cells and their effects on fuel cell performance that may not be evident from experimental work. In this thesis, a 2-D steady-state cathode model of a proton-exchange-membrane fuel cell (PEMFC) is developed. The kinetics of the cathode half-reaction were investigated, specifically the reaction order with respect to oxygen concentration. It is unknown whether this reaction order is one or one half. First- and half-order reaction models were simulated and their influence on the predicted fuel cell performance was examined. At low overpotentials near 0.3 V, the half-order model predicted smaller current densities (approximately half that of the first-order model). At higher overpotentials above 0.5 V, the predicted current density of the half-order model is slightly higher than that of the first-order model. The effect of oxygen concentration at the channel/porous transport layer boundary was also simulated and it was shown the predicted current density of the first-order model experienced a larger decrease (~10-15% difference at low overpotentials) than the half-order model. Several other phenomena in the cathode model were also examined. The kinetic parameters (exchange current density and cathode transfer coefficient) were adjusted to assume a single Tafel slope, rather than a double Tafel slope, resulting in a significant improvement in the predicted fuel cell performance. Anisotropic electronic conductivities and mass diffusivities were added to cathode model so that the anisotropic structure of the porous transport layer was taken into account. As expected, the simulations showed improved performance at low current densities due to a higher electronic conductivity in the in-plane direction and decreased performance at high current densities due to smaller diffusivities. Additionally, the concentration overpotential was accounted for in the model; however it had little influence on the simulation results.en
dc.format.extent1040075 bytes
dc.format.mimetypeapplication/pdf
dc.languageenen
dc.language.isoenen
dc.relation.ispartofseriesCanadian thesesen
dc.rightsThis publication is made available by the authority of the copyright owner solely for the purpose of private study and research and may not be copied or reproduced except as permitted by the copyright laws without written authority from the copyright owner.en
dc.subjectPEM Fuel Cellsen
dc.subjectReaction Kineticsen
dc.titleMathematical Modeling of PEM Fuel Cell Cathodes: Comparison of First-Order and Half-Order Reaction Kineticsen
dc.typeThesisen
dc.description.degreeMasteren
dc.contributor.supervisorKaran, Kunalen
dc.contributor.supervisorMcAuley, Kimberly B.en
dc.contributor.supervisorBeale, Steven B.en
dc.contributor.departmentChemical Engineeringen


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