Unified mechanical and fluidic analyses of serpentine channel flows in metallic bipolar plates under the influence of locally deformed porous gas diffusion layers

Unified conceptual systems of structural and flow dynamics are introduced to predict effects of porous gas diffusion layer (GDL) deformation on performance of polymer electrolyte fuel cells (PEFCs) by computational approaches. Static analysis is first performed to obtain local variations of GDL by stacking pressures. A number of case studies with selected key design parameters are conducted to figure out mechanical characteristics of GDLs contacting metallic bipolar plates. Successively, it is possible to apply the volumetric changes of the compressed GDLs to determine fluidic characteristics in serpentine gas supplying channels with trapezoidal cross-section area on the metallic plates. One of the distinctive features of the present study is the concept of bypass flow through the GDLs by the flow resistance difference over the entire computational domain. Channel flows in the metallic bipolar plates are investigated using a simplified theory based on entropy generation minimization theories. These multi-disciplinary modeling efforts are well suited for evaluating the fluidic performance of PEFCs and further applied to develop the optimized metallic bipolar plate designs