Coupled FEM and CFD Modeling of Structure Deformation and Performance of PEMFC Considering the Effects of Membrane Water Content

Abstract

Based on a coupled finite element method (FEM) and computational fluid dynamics (CFD) model, the structural deformation and performance of a proton exchange membrane fuel cell (PEMFC) under different membrane water contents are studied. The water absorption behavior of the membrane is investigated experimentally to obtain its expansion coefficient with water content, and the Young’s modulus of the membrane and catalyst (CL) are obtained through a tensile experiment. The simulation results show that the deformation of the membrane increases with water content, and membrane swelling under the channel is larger than that under the rib, forming a surface bump under the channel. The structural changes caused by the membrane water content have little effect on the performance of PEMFC in the low-current density range; while its influence is significant in the medium- and high-current density range. A medium membrane water content value of 12 achieves the best fuel cell performance due to the balance of membrane resistance and mass transport.

An Effective Force-Temperature-Humidity Coupled Modeling for PEMFC Performance Parameter Matching by Using CFD and FEA Co-Simulation

“…In addition to the GDL deformation, some recent studies have also taken into account the performance parameters of the water content in the membrane. Dong et al [21] built a coupled FEM and CFD model, and the structural deformation of the fuel cell membrane and the PEMFC performance were all investigated with different water contents of the membrane. The results showed that the PEM deformation increased with the water content, which resulted in an uneven GDL surface under the BPP channels and ribs.…”

“…Considering the multi-coupled behaviors in the fuel cell, the FEM and CFD are con-simulated for this situation. The FEM is an efficient and commonly used computational method that discretizes a continuous structure into several finite-sized elements to solve continuum mechanics problems [21]. The CFD is an approximate representation of the integral and differential terms in the control equations of the fluid dynamics into discrete algebraic form, making it a system of algebraic equations, and then solving these discrete systems of algebraic equations to obtain numerical solutions at discrete time/space points.…”