关键词: 液体火箭发动机；再生冷却；推力室；瞬态导热；热应力；结构分析；流固耦合

Abstract: To predict the strain distribution of regeneratively cooled LRE thrust chamber wall，and to study the failure mechanism of inner wall，three dimensional transient thermal analysis of thrust chamber wall is carried out，with finite element method，and three dimensional transient loading elastic-plastic structural analysis using multilinear kinematic hardening model is presented further. The calculated results indicate that multilinear kinematic hardening model can accurately model the stress-strain response of thrust chamber inner wall. The time to reach steady state of inner wall temperature is much shorter than that of outer wall temperature，about 0.1s later after pre cooling，hot run and post cooling phase. The inner wall temperature already approaches steady state. Three dimensional transient loading thermomechanical analysis demonstrates that the failure position of thrust chamber inner wall is located at the center of cooling channel，upstream of the throat. The calculated maximum residual strain based on transient loading is about 15.7% larger than that based on steady loading.

Key words: Liquid rocket engine；Regenerative cooling；Thrust chamber；Transient heat transfer；Thermal stress；Structural analysis；Fluid-structure interaction