An experimentally validated heat transfer model for thermal management design in polymer electrolyte membrane fuel cells

摘要

The temperature distribution in polymer electrolyte membrane fuel cells (PEMFCs) plays a vital role in defining the overall efficiency and in ensuring the delivery of optimum performance, and understanding the heat transfer taking place is essential for the design of effective thermal and water management systems. This article describes a simple model, validated against experiment, which can be used to investigate the factors such as bipolar plate design, materials of construction, and the external effects of forced convection such as cooling fans and natural convection. The model employs computational fluid dynamics to account for the reactant flows in composite graphite plates and heat distribution within the stack, while convective heat transfer from the external surface of the fuel cell is treated using well-known heat transfer correlations. The computational model was validated using a novel fuel cell analogue composed of an electrically controlled heating plate to simulate the heat generated by the membrane electrode assembly and instrumented with 14 calibrated thermocouples. The model showed good agreement with the experiment over a wide range of gas flowrates, both in terms of local temperature distribution and overall energy balance. This suggests that the novel experimental methodology reported here could be used to support the design of bipolar plates for optimum heat transfer.