Three-dimensional multi-phase simulation of different flow fields with cooling channel in proton exchange membrane fuel cell

Abstract

The overall performance of PEMFC (proton exchange membrane fuel cell) is affected by the flow field structure, especially the cathode flow field design can effectively solve the uneven distribution of gas concentration in the traditional flow channel and the cathode flooding phenomenon. In order to solve the above problems, a PEMFC single cell model with waveform staggered flow field of cooling flow field and small cathode channel was established in this study. Three-dimensional (3D) multi-phase CFD (computational fluid dynamics) simulation method is used to compare with gas concentration, liquid water distribution, pressure drop, and net power density of three different cases, and the influence of different cooling velocity on the temperature of cooling flow field is considered. The results show that the overall performance of the proposed flow field is the best, in which the maximum current density is 1.391 A⋅cm−2 and increases by 14.9%. The cathode and anode waveform staggered flow field makes the proton exchange membrane (PEM) water distribution more uniform, at the same time, the small size of the cathode flow channel facilitates the discharge of heat, and the convective heat transfer effect is enhanced. The electrochemical reaction rate is fast, which accelerates the temperature reduction in the fuel cell under the action of the cooling flow field, and the temperature uniformity of the cooling flow field is better. In addition, net power density is improved by 39.7%, and the output performance is significantly improved.