复杂力热载荷下推力室内壁失效机理研究  

Study on Failure Mechanism of Thrust Chamber Liner Wall under Complex Thermal Load

作　　者：吴有亮 刘潇 孙冰[2] 金平[2] 田原[1] WU Youliang;LIU Xiao;SUN Bing;JIN Ping;TIAN Yuan(Bejing Aerospace Propulsion Institute,Bejing 100076,China;School of Astronautics,Beihang University,Bejing 100191,China)

机构地区：[1]北京航天动力研究所低温液体推进技术实验室,北京100076 [2]北京航空航天大学宇航学院,北京100191

出　　处：《强度与环境》2024年第1期31-36,共6页Structure & Environment Engineering

基　　金：民用航天科研工程项目(D010103)。

摘　　要：大推力氢氧火箭发动机在经过多次试车后,推力室内壁会产生不同程度的裂纹,严重影响发动机的工作可靠性。为了分析复杂力热载荷下推力室内壁的失效机理,本文根据发动机实际工作过程涉及预冷-工作-后冷-松弛四个阶段,分别计算了经过单次和多次工作循环的内壁应力应变情况,并针对试车分解后的内壁材料进行断貌分析和金相检查。仿真与材料分析结果表明:内壁面的失效机理为疲劳和棘轮共同作用下导致通道中心点处残余拉应变不断累积,不断向外鼓起,而内壁材料在高温下会出现晶粒粗化和再结晶现象,导致材料性能出现不可逆的下降,加速了结构失效,最终产生裂纹。The liner wall of high-thrust hydrogen-oxygen rocket engine will crack in different degree after several tests,which will seriously affect the working reliability of the engine.In order to analyze the failure mechanism of thrust chamber wall under complex thermal load,according to the four stages of precooling-working-postcoolingrelaxation involved in the actual working process,the stress and strain of the inner wall after single and multiple working cycles are calculated respectively,and the crack failure analysis and metallographic analysis are carried out for the inner wall material after decomposing.The results of simulation and material analysis show that the failure mechanism of the inner wall is that the residual tensile strain accumulates at the central point of the channel under the action of fatigue and ratchet,and the grain coarsening and recrystallization occur in the inner wall material at high temperature,which leads to the irreversible decline of the material properties,accelerates the failure of the structure and eventually produces cracks.

关 键 词：推力室 失效机理 疲劳 断貌分析 裂纹 

分 类 号：V216.3[航空宇航科学与技术—航空宇航推进理论与工程] V217.32