A multiphysics across-the-channel model is presented for the anode of a liquid-feed Direct Methanol Fuel Cell (DMFC). The model considers both two-dimensional (2D) single-phase anisotropic transport of methanol in the anode gas diffusion layer (GDL) and anisotropic electron transport from the catalyst layer to the current collector rib, coupled to a one- dimensional (1D) model for the membrane and the cathode, which describes the electrochemical reactions kinetics, water and methanol crossover, and oxygen transport from the cathode channel to the cathode catalyst layer. As new contribution, the 2D model takes into account the effects of the inhomogeneous compression of the GDL associated with the repetitive rib-channel pattern, including non-uniform porosity, diffusivity and bulk electrical conductivity distributions, as well as non-uniform contact resistances over the GDL-rib and -membrane interfaces, which affect mass and charge transport phenomena. As a straightforward application, we have investigated the effect of the clamping pressure acting on the stack on the overall fuel cell performance.
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