Simulation of PEM Fuel Cell Stack Performance Under Varying Voltage Conditions Using CFD

This paper presents a comprehensive three-dimensional mathematical model developed to evaluate and simulate the performance of proton exchange membrane fuel cell stack. The study investigates critical parameters, including hydrogen molar fraction distribution, oxygen molar fraction distribution, temperature distribution within the cells, temperature variations in the membrane electrode assemblies, and water activity in the oxygen gas diffusion electrodes under different operating voltages (0.85 V, 0.75 V, 0.65 V, and 0.55 V). Utilizing COMSOL Multiphysics software, the model provides insights into the stack's dynamic behavior across varying conditions. It is found that as the operating voltage decreases, both hydrogen and oxygen consumption increase, leading to higher temperature gradients and more significant water production. These effects are especially pronounced at 0.55 V, where efficient cooling and water management become critical to avoid overheating and water flooding. The results demonstrate that optimal operating conditions are essential for balancing performance and durability, providing valuable data for the design and operation of fuel cell systems in practical applications.