温度循环载荷下药柱力学响应与累积损伤分析  

Mechanical response and cumulative damage analysis of grain under temperature cyclic loading

作　　者：杨庚 袁杰红[1,2] 孙海涛 申志彬 YANG Geng;YUAN Jiehong;SUN Haitao;SHEN Zhibin(School of Aerospace Science,National University of Defense Technology,Changsha 410073,China;Hunan Provincial Key Laboratory for Aerospace Mission Intelligent Planning and Simulation,Changsha 410073,China)

机构地区：[1]国防科技大学空天科学学院,湖南长沙410073 [2]空天任务智能规划与仿真湖南省重点实验室,湖南长沙410073

出　　处：《推进技术》2024年第11期171-178,共8页Journal of Propulsion Technology

基　　金：国家自然科学基金(12372203);湖南省杰出青年基金(2021JJ10046)。

摘　　要：针对机载固体火箭发动机在地面贮存和高空极端低温挂载的使用工况,开展了推进剂松弛及蠕变破坏试验获取相关材料参数,并基于热粘弹性本构,采用有限元法计算分析了药柱在温度循环载荷下温度场及力学响应,研究了挂飞时间对药柱温度场和应力应变场的影响规律,确定了某圆管星孔药柱危险点,并基于损伤模型对不同挂飞时间下发动机的失效挂飞次数进行了评估。结果表明,不同挂飞工况下药柱温度场和应变场分布规律相同,挂飞时间超过7 h后,药柱整体达到均匀温度场,此后随着挂飞时间的延长,应变增长幅度减弱;温度循环产生的交变热应力会导致药柱损伤累积,温度变化越快,造成的累积损伤越大,且随着挂飞时间的延长,失效挂飞次数逐渐缩短。Aiming at the working conditions of airborne SRM storage on the ground and extreme low-tem⁃perature mounting at high altitude,the propellant relaxation and creep damage test were carried out to obtain the relevant material parameters.And based on the thermo-viscoelastic principal structure,the finite element meth⁃od was used to calculate and analyze the temperature field and mechanical response of the grain under the temper⁃ature cyclic loading,and to study the influence of the captive flight time on the temperature field and the stress and strain field of the grain,and to determine the maximum principal stress/strain danger point of the grain under the different captive flight time,and the number of failure cycles of SRM under different captive flight times was evaluated based on the damage model.The results show that the temperature field and strain field distribution of the grain are the same under different captive flight time,and the grain reaches a uniform temperature field after the captive flight time exceeds 7 h,after which the strain growth is weakened with the increase of the captive flight time.The alternating thermal stresses generated by the temperature cyclic loading lead to the accumulation of damage in the grain,and the faster the temperature changes,the greater the cumulative damage of the grain,and the number of failures is gradually shortened with the increase of the captive flight time.

关 键 词：固体火箭发动机 推进剂药柱 温度循环 力学响应 损伤 挂飞时间 

分 类 号：V435[航空宇航科学与技术—航空宇航推进理论与工程]