An effective mesh strategy for CFD modelling of polymer electrolyte membrane fuel cells

Computational fluid dynamics (CFD) is a major tool in PEM fuel cell research. Typical three-dimensional PEM fuel cell models involve more than 106 mesh elements. This makes the computation very intense and necessitates a methodology to mesh the computational domain that can keep the number of elements to a minimum while maintaining good accuracy. In this study, the effect of computational mesh in each direction on the accuracy of the solution is investigated in a systematic way. It is found that the mesh in different directions has a different degree of influence on the solution suggesting that the mesh in one direction can be coarser than the other. The proposed mesh strategy is capable of greatly reducing the number of mesh elements, hence computation time, while preserving the characteristics of important flow-field variables. Moreover, it is applicable to a wide range of cell sizes and flow-field configurations and should be used as a guideline for mesh generation.