A dot matrix and sloping baffle cathode flow field of proton exchange membrane fuel cell

摘要

A novel dot matrix and sloping baffle flow field plate for proton exchange membrane fuel cell (PEMFC) cathode is designed. The plate consists of dispersive and arrayed blocks with sloping angles as shoulders. Features of the plate include a large fluid domain, and air guidance in two directions is achieved by sloping sides of the block. The cell output performance, internal transport process and liquid water removal process of the PEMFC with the matrix flow field are numerically investigated by three-dimensional two-phase full cell model and volume of fluid (VOF) model. The simulation results show that compared with the parallel and serpentine flow field, the matrix flow field can achieve high cell output performance by both improving oxygen supply to gas diffusion layer (GDL) and uniform distribution. Comparing five matrix flow fields with different block sizes and numbers shows that adequate contact area between the plate and GDL for current conductor is critical. For liquid water removal process in the matrix flow field, liquid water is hardly blocked by arrayed blocks and can leave GDL quickly. In summary, the matrix flow field fits high current density demand of PEMFC well, and some new perspectives on flow field design are presented.