火箭推进2024，Vol.50Issue(3)：75-82,8.DOI:10.3969/j.issn.1672-9374.2024.03.008
考虑尺寸效应的结构振动疲劳寿命评估方法
Evaluation method of vibration fatigue life of structures considering size effect
摘要
Abstract
In order to improve the evaluation precision of vibration life of key structure of liquid rocket engine under vibration environment,the size effect was introduced into vibration fatigue life analysis by using crack initiation characteristic volume hypothesis and dangerous volume subdivision series model,and the vibration fatigue volume life model was put forward,and its numerical model was established.Based on the vibration test data of key structural simulators,the small-scale vibration fatigue characteristic parameters of typical materials were identified,and the life data maximum likelihood of simulation and test was used to optimize the crack initiation characteristic length.The model was verified by the vibration fatigue test of the key structure simulators.It is found that for the two simulators,the distribution of vibration life of each load order covers the test data,and the average life of the original state is within 1.5 times the dispersion band of the test,and the improved state is within 2 times the dispersion band of the test.The accuracy and applicability of the method were proved.关键词
振动疲劳/尺寸效应/寿命/极大似然/裂纹萌生Key words
vibration fatigue/size effect/life/maximum likelihood/crack initiation分类
航空航天引用本文复制引用
杨茂,时寒阳,王珺,樊勋..考虑尺寸效应的结构振动疲劳寿命评估方法[J].火箭推进,2024,50(3):75-82,8.基金项目
国家重点实验室基金(HTKJ2022KL011004) （HTKJ2022KL011004）
