基于开裂能密度的柔性接头摆动疲劳寿命预测  

Prediction of the swing fatigue life of flexible joint based on cracking energy density

作　　者：张金尧 任军学[1] 薛牧遥 童悦 郑庆 汤海滨[1] ZHANG Jinyao;REN Junxue;XUE Muyao;TONG Yue;ZHENG Qing;TANG Haibin(School of Astronautics,Beihang University,Beijing 100191,China;Xi’an Aerospace Solid Propulsion Technology Institute,Xi’an 710025,China;Shanghai Space Propulsion Technology Research Institute,Shanghai 200125,China)

机构地区：[1]北京航空航天大学宇航学院,北京100191 [2]西安航天动力技术研究所,西安710025 [3]上海航天动力技术研究所,上海200125

出　　处：《航空动力学报》2024年第10期50-58,共9页Journal of Aerospace Power

基　　金：基础加强计划技术领域基金(2020JCJQJJ014)。

摘　　要：为准确预测柔性接头的摆动疲劳寿命,将开裂能密度作为驱动弹性件疲劳裂纹扩展的损伤参量,借助材料的疲劳裂纹扩展试验和单轴拉伸疲劳试验建立了柔性接头的摆动疲劳寿命预测模型,并用有限元分析结果计算了柔性接头在12.3 MPa、6°摆角工况下的开裂能密度,进而对柔性接头的摆动疲劳寿命进行预测。结果表明:预测试验工况下柔性接头的摆动疲劳寿命为107次,实测寿命为120次,两者较为一致,且预测的裂纹位置和开裂平面与实际试验的失效位置较为吻合。模型预测柔性接头的摆动疲劳寿命与实测疲劳寿命之比为1/1.12,分布在2倍分散因子之内,满足工程疲劳寿命的预测要求。In order to accurately predict the swing fatigue life of flexible joint,the cracking energy density(CED)was used as the damage parameter to drive the fatigue crack growth of elastomers.The swing fatigue life prediction model of flexible joint was established by means of fatigue crack growth test and uniaxial tensile fatigue test.The CED of flexible joint under 12.3 MPa and 6°swing angle was calculated by using the finite element analysis results,and then the swing fatigue life of flexible joint was predicted.The results showed that the predicted swing fatigue life of the flexible joint under the test condition was 107 cycles,which was consistent with the measured fatigue life of 120 cycles,and the predicted crack location and crack plane were in good agreement with the failure position of test.The ratio of predicted life to measured life was 1/1.12 within the double dispersion factor,which was acceptable in engineering.

关 键 词：疲劳寿命预测 柔性接头 开裂能密度 裂纹扩展 有限元分析 固体火箭发动机 

分 类 号：V431[航空宇航科学与技术—航空宇航推进理论与工程]