Thermal Analysis of Turbine Blades with Thermal Barrier Coatings Using Virtual Wall Thickness Method

Abstract

A virtual wall thickness method is developed to simulate the temperature field of turbine blades with thermal barrier coatings (TBCs), to simplify the modeling process and improve the calculation efficiency. The results show that the virtual wall thickness method can improve the mesh quality by 20%, reduce the number of meshes by 76.7% and save the calculation time by 35.5%, compared with the traditional real wall thickness method. The average calculation error of the two methods is between 0.21% and 0.93%. Furthermore, the temperature at the blade leading edge is the highest and the average temperature of the blade pressure surface is higher than that of the suction surface under a certain service condition. The blade surface temperature presents a high temperature at both ends and a low temperature in the middle height when the temperature of incoming gas is uniform and constant. The thermal insulation effect of TBCs is the worst near the air film hole, and the best at the blade leading edge. According to the calculated temperature field of the substrate-coating system, the highest thermal insulation temperature of the TC layer is 172.01 K, and the thermal insulation proportions of TC, TGO and BC are 93.55%, 1.54% and 4.91%, respectively.