Local creep buckling analysis method of combustor liner

In consideration of the "local" feature of combustor liner temperature field and stress field, a concept of "local creep buckling" was presented in this paper along with an engineering analysis method. Firstly, the theoretical model of creep buckling was established based on Hoff theory. Secondly, the feasibility of using finite element method (FEM) to analyze creep buckling was validated by theoretical and test data. Thirdly, a statics analysis with thermal-mechanical loads was performed, and then the dangerous place of combustor liner local creep buckling was captured considering creep buckling instability factors. Finally, sub-model technique was used in nonlinear thermal elastic-plastic/creep finite element analysis to capture the critical time of local creep buckling with "curvature local maximum point" criterion. It could be concluded that, as compared with traditional method, the hypothesis of average temperature, average compressive stress and plane strain could be improved in this paper, thus the computational accuracy was enhanced greatly. The work of this paper is significant on the application of structure design of combustor liner.