ONE DIMENSIONAL MODELING AND SIMULATION OF HEAT AND MASS TRANSFER IN MEMBRANE OF POLYMER ELECTROLYTE MEMBRANE FUEL CELL

Abstract

A transient, one-dimensional heat and mass transfer model in membrane of a proton exchange membrane fuel cell, is presented. The role of the membrane is to transport protons from the anode to cathode of the fuel cell while preventing the transport of other reactants. The membrane is modeled assuming mono-phase, multi-species flow. For water transport, the principle driving forces modeled are a convective force, an osmotic force (i.e. diffusion), and an electric force. The first of these results from a pressure gradient, the second from a concentration gradient, and the third from the migration of protons from anode to cathode. Equations are developed for the conservation of mass and conservation of thermal energy. The model is solved using fully implicit finite difference approach. Results showing the effects of current density, pressure gradients, and water and heat fluxes on water concentration, and temperature, across the membranes like Nafion 112, Nafion115 & Nafion117. Also the polarization curve is drawn in order to show the output power comparison of all these three types of membranes, and it was found that under existing conditions Nafion 112 proved to be the most suitable out of all these three types of membrane.