NUMERICAL ANALYSIS FOR A VAPOR FEED MINIATURE DIRECT METHANOL FUEL CELL SYSTEM

A two-dimensional, multiphase model is presented and analyzed for a vapor feed DMFC system. The DMFC model is based on the multiphase mixture formulation and encompasses all components in the porous regions of a vapor feed DMFC using a single computation domain. The evaporation/condensation phenomenon in the anode flow channel is modeled in a separated way. An iterative numerical scheme is used to solve the governing equations in a coupled manner. Numerical simulations are carried out to explore the transient and polarization characteristics of the DMFC, including methanol crossover through the membrane, temperature evolution, anodic and cathodic overpotentials. The results indicate the anode flow channel for the feeding methanol solution is the key parameter for the DMFC performance. The numerical results are also compared with the experimental data in a good agreement.