Cerium lanthanum zirconate ceramic is hopeful to be the next generation of thermal barrier coatings, but the thermal stress and deformation will shorten the working life. In this paper, the two dimensional geometric models based on possible designed porthole were implemented to simulate the real thermal ablation. Afterwards, the influence of shapes of portholes on the distribution of coating temperature, displacement along the interface between the bond layer and the top layer, XY-shear stress and von-Mises stress was carried out to verify the above numerical calculations. The temperature results show cerium lanthanum zirconate ceramic can protect superalloy at the working condition of 1600 degrees C well. The Y displacement between the bond and ceramics layer was used to measure the peeling of top layer after the thermal ablation. The stress caused by the difference of deformation rate was used to predict the most dangerous area. All the results reveal that the semi-circle porthole is the best choice for extending the working time.