Critical investigation of microchannel design effect on thermal performances of a PEM fuel cell

Abstract

A major challenge for improving the characteristics of fuel cells is to obtain uniform tempera-ture distribution during its operation, in which a major part of hydrogen chemical energy is converted to heat. If not properly exhausted, this exothermic chemical reaction causes over-heating in the polymer electrolyte membrane fuel cells (PEMFCs), leading to a reduction in their performance. Hence, analyzing different techniques for PEMFCs cooling may be nec-essary for this kind of energy systems. In this study, four microchannel design effect on alu-minum oxide (Al2O3) nanofluids thermal behavior in cooling plates with 1400×1800 mm2 was investigated using computational fluid dynamic (CFD) simulation. The performances of proposed microchannel designs were evaluated in terms of maximum and uniformity tem-perature. The suggested study has been validated by available published results from previous research studies. The obtained results depicted that the maximum temperatures have been 305.3K and 305.5K for S- character flow field and two stages coolant flow field microchannel designs, respectively. The results revealed that the multi-flow plate designs might greatly en-hance the performance of PEMFCs in terms of temperature distribution in the cooling plate when compared to standard flow field designs. Another important finding was that the two stages microchannel and S-design are more thermal stable compared with other microchan-nels.