An Advanced BEM for Thermal and Stress Analyses of Components with Thermal Barrier Coating

Abstract

An advanced boundary element method (BEM) for 2-D steady-state thermal analysis of components with thermal barrier coating (TBC) is presented in this paper. First, a scheme of evaluating the nearly singular integrals in stress analysis of a thin body was extended to the thermal analysis of components with TBC. Then the BEM formulation for thermal analysis of multi-layered structures was developed. Next, an advanced BEM was developed for 2-D interfacial stress analysis of components with TBC. The non-linear transformation scheme in stress analysis of thinbody under traction load by BEM was extended to evaluate the nearly singular integral in BEM for thermal and centrifugal stress analysis. Then BEM formulation for multi-layer structure under thermal, centrifugal and traction loads was presented. Several numerical examples of 2-D thermal analyses and interfacial stress analyses of components with TBC were analyzed with only 32 boundary elements. The accurate numerical results can be obtained even when the ratio of the coating thickness to element length approached 10 ^-9. The maximum relative percentage errors of interfacial tangent tension stresses under a complex temperature field, traction and centrifugal loads were 0.08%, 0.13% and 0.23%, respectively,. The present BEM will be an efficient tool for TBC design and TBC peeling-failure analysis.