Multi-objective optimization of operating conditions of an enhanced parallel flow field proton exchange membrane fuel cell

Abstract

Proton Exchange Membrane Fuel Cell (PEMFC) is a high-efficiency energy conversion device. Operating conditions play a vital role to obtain maximum power. In the present work, a modified parallel PEMFC is modeled by 3D multiphase computational fluid dynamics simulation. Water management and reactants transport are studied in solitary changes of temperature, pressure, mass flow rate, and humidity ratio to get an interpretation in the PEMFC operation. Mutual effects of operating parameters including cathode stoichiometry, anode stoichiometry, temperature, pressure, cathode relative humidity, and anode relative humidity are studied to obtain an optimal power density in all operating voltages. Response Surface Method (RSM) and Non-dominated Sorting Genetic Algorithm ii (NSGA ii) were combined to consummate a multi-objective optimization. Technique of Order Preference Similarity to the Ideal Solution (TOPSIS) was utilized to select the ideal case from the Pareto front. The voltage and amount of maximum power density of each operating condition are selected as objects of the optimization. The validated results show each operating parameter can play a positive or negative role in the performance due to the other operating conditions. The increase of temperature and pressure can have a beneficial effect only with appropriate stoichiometries of fuel and air and adequate relative humidities. High stoichiometries of cathode and anode result in the high amount of the maximum power density and contrary, the low range of stoichiometries leads to the high voltage of the maximum power density.