Modeling Temperature Distributions in Thermal Barrier Coatings with Various Thicknesses

Abstract

The geometric model of thermal barrier coatings (TBCs) was established. Two cases based on the standard thickness of the ceramic layer existed. These were the steps of TBCs thickness were being higher than the standard layer and those of lower than standard layer. The heat transfer processes of these two cases were simulated with the ANSYS software. The change process of thermal effusivity was analyzed in the two cases and the coating thickness differences effect on the surface temperature distributions of TBCs was analyzed through the time course curves of temperature difference. Moreover, the difficulty of detection for these two cases with infrared nondestructive testing was discussed according to maximum temperature difference and the maximum temperature contrast ratio. The result demonstrated that all curves of thermal effusivity with various thickness differences coincided with each other at the initial and longer times, where the ceramic layer thickness was lower than the standard layer. This was more easily detectable compared to the higher thickness and the maximum temperature contrast ratio or the maximum temperature difference increased as the coating thickness difference increased.