Study on heat and mass transfer in PEMEC parallel channels with different inlet boundary shapes using local optimization algorithms

This study develops a 3D non-isothermal numerical model for PEMEC to address two major defects of traditional parallel flow channels, namely uneven fluid distribution and local overheating. Two new inlet boundary structures including triangular and irregular shapes are proposed and optimized by a local optimization algorithm, taking the dispersion of inter-channel mass transfer rates as the optimization target. Simulation results indicate that optimized structures improve fluid distribution uniformity by up to seven times and reduce temperature difference by about 45 percent, while lifting current density and gas production. Linear fitting of the two optimized inlet shapes creates a reference curve, proving that inlet boundaries conforming to this curve can preserve outstanding hydrothermal transport performance. For linear inlet boundaries with slopes smaller than the fitted curve, water distribution uniformity presents an approximately linear relation with slope. The research outcomes provide some references for future PEMEC channel design.