耦合临界平面-临界距离理论的缺口结构疲劳寿命预测  

FATIGUE LIFE PREDICTION OF NOTCHED STRUCTURE USING COMBINED CRITICAL PLANE-CRITICAL DISTANCE APPROACH

作　　者：廖鼎 朱顺鹏 高杰维 牛晓鹏 何金超 LIAO Ding;ZHU ShunPeng;GAO JieWei;NIU XiaoPeng;HE JinChao(School of Mechanical and Electrical Engineering,University of Electronic Science and Technology of China,Chengdu 611731,China)

机构地区：[1]电子科技大学机械与电气工程学院,成都611731

出　　处：《机械强度》2023年第2期454-461,共8页Journal of Mechanical Strength

基　　金：国家自然科学基金项目(11972110,12232004);四川省重点研发计划(2021YFG0210)资助。

摘　　要：工程中,为满足各种功能性需求,几何不连续特征广泛存在;同时,受疲劳影响的结构在服役时大都承受复杂多轴载荷作用。因而,亟需精确的缺口结构多轴疲劳寿命预测模型为结构抗疲劳设计及安全使役保障提供理论支撑。通过将临界平面法中经典的Fatemi-Socie模型与临界距离理论结合,提出了一种多轴载荷作用下缺口结构疲劳寿命预测方法,并以TC4轴肩试件疲劳试验数据验证了其有效性。结果显示,该方法可克服直接基于危险点应力应变数据预测寿命时的保守估计问题,预测值与真实值误差在2倍以内。最后,将该方法应用于某压气机盘疲劳寿命预测。In engineering practice,due to various functional requirements,structures with geometric discontinuities occur widely;in addition,most structures undergo complex multiaxial loads,which drives the development of relevant theories.As a result,to provide reference for structural anti-fatigue design and ensuring their operation safety,the establishment of fatigue lifing methods for notched components under multiaxial loads is critical and indispensable.In this paper,by combining the popular Fatemi-Socie critical plane model with the critical distance theory,a fatigue lifing model for notched structures under multiaxial loads was established,and its effectiveness was verified with the fatigue test data of TC4 stepped shaft specimens.Results show that the proposed model can overcome the conservative estimation problem when performing fatigue lifing based on the stress-strain data of critical points,with all predicted fatigue lives within two-time error bands.Finally,the method was applied to the fatigue life prediction of a turbine compressor disc.

关 键 词：疲劳 缺口 压气机盘 临界平面 临界距离 寿命预测 

分 类 号：V215.5[航空宇航科学与技术—航空宇航推进理论与工程]