Damage and Creep Behavior in Planar Solid Oxide Fuel Cell by Modeling of Multiphysics Coupled

A multiphysics-coupling model of solid oxide fuel cell (SOFC) was proposed via a software named COMSOL Multiphysics for the establishment of coupled fields of electrochemical-gas, flow-matter and transfer-temperature. The inhomogeneous temperature distribution obtained from the numerical analysis was applied to the corresponding model build by ABAQUS as a thermal load, and the creep damage subroutine developed based on the Wen–Tu creep ductile depletion model was used to analyze the creep damage of SOFC. The creep damage behavior of SOFC was investigated and the creep crack propagation was predicted. The results show that the creep deformation and damage of SOFC components firstly increase and then remain unchanged. The lower connector is the first to reach the critical damage value, which is the potential dangerous area and is the most likely to failure. After 50000 h, two creep damages occur in SOFC. The maximum crack is 1.6 mm as the non-penetrating crack that occurs at the junction of 1.1 mm in the air inlet of the lower connector and the cathode material. Compared with the overall structure size, the smaller crack will not cause gas leakage, thus meeting the requirement of commercial safe operation for 40000 h.