CFD Investigation of Microchannel design effect on Al2O3 Nano-fluids Thermal Behavior in PEM fuel cell cooling plate

Abstract

A uniform temperature distribution is important to obtain better control and higher performance of polymer electrolyte membrane fuel cells (PEMFCs). In PEMFCs, more than half of the chemical energy of hydrogen is converted into heat during the electrochemical generation of electricity. If not being properly exhausted, this reaction heat overheats the PEMFCs and thus impairs their performance. In general, large-scale PEMFCs are cooled by Nanofluid that circulates through coolant flow channels in cooling plates. In this study, detailed fluid flow and heat transfer in large scale cooling plates with 140× 180 cm2 was simulated using a commercial computational fluid dynamics (CFD) .Based on the CFD simulations, the performances of three different coolant flow field designs were assessed in terms of the maximum temperature, temperature uniformity, and pressure drop characteristics, and compare it to a straight traditional flow field. The results demonstrated that –S- character flow field designs could significantly improve the uniformity of temperature distribution in a cooling plate compared with other zigzag flow field designs, despite the high Nanofluid (Al2O3-W(60)/EG(40)) pressure drop.