Numerical and experimental investigation on 25 cm² and 100 cm² PEMFC with novel sinuous flow field for effective water removal and enhanced performance

Abstract

Commercial viability of fuel cells is limited as it does not produce the same power density while scaling and stacking, generation and safe storage of hydrogen is another snag. This work addresses water lodging at cathode (a scaling issue) through a novel sinuous flow field both numerically and experimentally, by scaling up of PEMFC from 25 cm²to 100 cm². Conventional serpentine flow field of 25 cm²widely studied in literature is experimented to validate the numerical model in a multiphysics tool. The model developed was applied to sinuous flow field of 25 cm²and the results revealed better water removal and 7.7% higher power density than serpentine flow field due to inter channel diffusion and under rib convection. In order to increase power density further the dwell time at anode has to be increased in sinuous flow field, hence anode side flow field was made serpentine while retaining sinuous flow field at cathode. This combination enhanced the performance the power density by about 14%. This serpentine-sinuous combination was then scaled to 100 cm²and experimented, revealing a lower power drop than serpentine flow field.