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Thermodynamic analysis of equilibrium products and heat requirements is conducted for C8H18 (octane), CH4O (methanol), C2H6O (ethanol) and C3H8 (propane) at specified temperature and pressure. The equilibrium calculation utilizes the NASA equilibrium code by Gordon and MacBride. The temperature range is from 600 to 1700 K, and the pressure is set at 1 bar. The equilibrium calculation shows that the adiabatic temperatures are generally below 1300 K, except for C2H6O and C3H8 at their respective partial oxidation conditions considered in this paper. Calculation also shows that the presence of H2O in the reactant mixture yields high conversion of H2 at temperature above 1200 K, and above which the H2 mole fraction is relatively independent of the mixture temperature. Negligible C(graphite) is predicted for conditions with temperature above 1200 K.

Two mathematical models for the catalyst layer of a PEMFC, i.e. the macro-homogenous model and the agglomerate model are evaluated in this paper. The characteristics of both models and the application of both models to optimal design of catalyst layer are discussed. The one-dimensional governing equations of both models are solved analytically or numerically using the finite difference method. A simplified, analytic solution of the macro-homogenous model under ideal conditions is derived. Parametric study and sensitivity analyses are performed for the agglomerate model to identify the parameters that have significant influences on the performance of a PEMFC. Several parameters including the electrolyte thickness, porosity, oxygen permeability, and layer thickness are found to affect the limiting current significantly. A solid model is developed to visualize the structure of a catalyst layer. This solid model is used to estimate effective transport properties.