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arXiv · nlin/0606061

Ignition and Front Propagation in Polymer Electrolyte Membrane Fuel Cells

Abstract

Water produced in a Polymer Electrolyte Membrane (PEM) fuel cell enhances membrane proton conductivity; this positive feedback loop can lead to current ignition. Using a segmented anode fuel cell we study the effect of gas phase convection and membrane diffusion of water on the spatiotemporal nonlinear dynamics - localized ignition and front propagation - in the cell. Co-current gas flow causes ignition at the cell outlet, and membrane diffusion causes the front to slowly propagate to the inlet; counter-current flow causes ignition in the interior of the cell, with the fronts subsequently spreading towards both inlets. These instabilities critically affect fuel cell performance.

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J. B. Benziger, E. -S. Chia, Y. De Decker, I. G. Kevrekidis. 2006-06-26. Ignition and Front Propagation in Polymer Electrolyte Membrane Fuel Cells. https://arxiv.org/abs/nlin/0606061

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