Thermal Stress Analysis of Solid Oxide Fuel Cell with Z-type and Serpentine-Type Channels Considering Pressure Drop

A thermo-electro-chemo-mechanical coupled 3D model was applied to simulate the performance and thermal stress of a double-sided cathode structured solid oxide fuel cell (DSC-SOFC) with two different air channel configurations: Z-type parallel and triple-parallel serpentine. The distribution of temperature, current density, fuel gas and thermal stress under different voltages in DCS-SOFC was illustrated, and the output power density of the cell was analyzed considering both the electrochemical power and the dissipative power caused by the pressure drop. It was found that the Z-type parallel cell gave a better performance under a low current density, while the triple-parallel serpentine cell was more efficient at a current density higher than 6330 A·m−2. A comparison of thermal stress distributions between the two flow field designs showed a small difference in maximum 1st principle stresses under the same operational voltages. Compared to the Z-type parallel flow field, the maximum 1st principle stress in the triple-parallel serpentine was much smaller under the same current density or electrochemical power, while much larger under the same output power.