Numerical Simulation Of The Stress Field Of The PEN For SOFC

The Solid Oxide Fuel Cell (SOFC) is a new type all solid-state energy conversion device operated at high temperatures with the advantages of high efficiency, fuel adaptability, fuel reformed within cell, no need using the precious metal electrode, good modularity and site fixed flexibility, etc. Therefore, the SOFC has become a very hot research subject in the domain of Fuel Cell.Considering the structural characteristic of the PEN and the working conditions of the SOFC, it is made to simulate the thermal stress distribution of the PEN on the basis of the thermal stress theory and the finite element analysis. Using the Visual C++ program to build the interpolation function of the temperature, put the previously temperature data into the thermal apply in this simulation, then calculate the thermal stress field for planar PEN and corrugated PEN. Combining the advantages of the two structures, raise a new structure: steric octagon PEN, and simulate out the thermal stress field.1) Through comparing the three different structures,the simulation results show that the planar PEN's maximal stress and displacement is higher than the corrugated PEN and the steric octagon PEN's, the stress and the displacement value of the steric octagon PEN is the minimum, which testify the structure stability of the steric octagon PEN.2) Through comparing PEN under the different working conditions, such as the direction, the rate and compose of the gas, the simulation results show that the PEN structure in co-flow condition is more stable than that in counter-floe condition. The temperature and the thermal stress increase with the rate of the gas and the content of the H2 in the fuel gas. The planar PEN is affected most by the working conditions in the three structures, while the steric actagon PEN is affected least.3) Comparing the thermal stress in the anode, electrolyte, cathode and two interfaces of any two layers of above, the simulation results show that the maximal thermal stress occur at the interface of the anode and the electrolyte, which is cause by the thermal expansivity making the PEN bend to the anode layer.