Influence of perforated gas diffusion layer micropore shape parameters on water removal in a proton exchange membrane fuel cell flow channel

To investigate and optimize the water-gas transport performance of microporous gas diffusion layer (GDL) flow channel, the simulation of computational fluid dynamics (CFD) is implemented with the volume of fluid method (VOF). The impact of microporous GDL flow channel with different depths, radiuses, and spacings on water transport and water removal is discussed. With the increase of microporous depth, the droplet movement velocity gradually accelerates. When the droplet returns to GDL, the peak of drag reduction rate increases first and then decreases and the peak of pressure drop tends to rise. The micropore radius has a few effects on droplet movement velocity, but it has obvious effects on the velocity field, pressure drop, and drag reduction rate. The influence of the spacing on the water droplet movement velocity and pressure drop is inconspicuous, but it has certain influence on drag reduction rate of the droplet returning to GDL and the microporous GDL velocity field. When the depth is 50 μm, radius is 50 μm, and spacing is 200 μm, the flow channel has a better drag reduction performance. The work in this paper provides a guide for the design of the microporous GDL for drag reduction and water removal. Highlights The impact of microporous GDL flow channel with different depths, radiuses, and spacings on water transport and water removal is discussed. The resistance can be reduced, and water removal can be accelerated greatly in the perforated GDL. When the micropore depth is 50 μm, radius is 50 μm, and spacing is 200 μm, the flow channel has a better drag reduction performance.