SEMI-EMPIRICAL FLOW AND PRESSURE DISTRIBUTION MODELING OF A FLOWING ELECTROLYTE DIRECT METHANOL FUEL CELL STACK

The pressure distribution across a flowing electrolyte direct methanol fuel cell (FE-DMFC) stack was numerically evaluated using semi-empirical equations for friction and loss coefficients. The stack is considered to have "U" shape manifold design with parallel serpentine fuel channels. The flow is assumed to be laminar and the flow rate in each cell of the stack is determined using the Hardy-Cross method. The results show that, the mass flow rate of methanol is greater at the inlet and declines as the fuel travels further within the stack manifolds. It was further discovered that pressure drop inside the inlet manifolds increases with stack length while the pressure drop inside the individual cell channels tend to decrease with stack length. Finally, the stack power output is estimated by assuming single cell power outputs at various operating current densities and methanol inlet flow rates based on experimental data obtained from the literature.