航空学报 > 2017, Vol. 38 Issue (2): 220376-220382   doi: 10.7527/S1000-6893.2016.0210

基于对数正态分布的多部位疲劳结构的疲劳寿命预测方法

谭秀峰1, 谢里阳1, 马洪义1, 张娜2, 罗义建2   

  1. 1. 东北大学 机械工程与自动化学院, 沈阳 110819;
    2. 中国第一汽车股份有限公司 技术中心 汽车振动噪声与安全控制综合技术国家重点实验室, 长春 130011
  • 收稿日期:2016-04-27 修回日期:2016-07-11 出版日期:2017-02-15 发布日期:2016-08-15
  • 通讯作者: 谢里阳,E-mail:lyxie@me.neu.edu.cn E-mail:lyxie@me.neu.edu.cn
  • 基金资助:

    国家自然科学基金(51335003);辽宁重大装备制造协同创新中心资助项目

Fatigue life prediction method for multi-site fatigue structure with lognormal fatigue life

TAN Xiufeng1, XIE Liyang1, MA Hongyi1, ZHANG Na2, LUO Yijian2   

  1. 1. College of Mechanical Engineering and Automation, Northeastern University, Shenyang 110819, China;
    2. State Key Laboratory of Vehicle NVH and Safety Technology, R & D Center, China FAW Ltd. Co., Changchun 130011, China
  • Received:2016-04-27 Revised:2016-07-11 Online:2017-02-15 Published:2016-08-15
  • Supported by:

    National Natural Science Foundation of China (51335003); Project supported by the Collaborative Innovation Center of Major Machine Manufacturing in Liaoning Province

摘要:

以实现多部位疲劳结构的寿命预测为目的,基于概率累积损伤法则,推导了基于寿命服从对数正态分布的概率疲劳寿命预测方法。根据损伤临界值与应力水平无关这一前提条件,将损伤临界值由传统确定性的值1转换为随机变量,累积损伤由确定性的中值损伤计算,建立了“中值累积损伤-概率损伤临界值”干涉模型。当对数寿命标准差恒定时,对比了所提出模型和基于Monte Carlo仿真的Miner累积损伤方法的寿命预测结果,验证了模型的准确性以及其方便快捷的优点;当对数寿命标准差变化时,损伤临界值由满足损伤等效的应力基准决定,此时亦可得到高精度的偏于安全的寿命预测结果。

关键词: 多部位疲劳, 疲劳寿命, 可靠性, 中值损伤, 概率损伤临界值, Monte Carlo仿真

Abstract:

To predict the fatigue life of multi-site fatigue structure, a probabilistic fatigue life prediction method based on the probabilistic accumulated damage rule is proposed, considering that fatigue life obeys lognormal distribution. According to the precondition that the damage critical value is independent of stress level, the damage critical value is transformed from the traditionally deterministic value 1 into a random variable, and the accumulated damage is calculated by the median S-N curve. An accumulated damage-probabilistic damage critical value interference model is thus built. When logarithmic fatigue life standard deviation is constant, life prediction result of the proposed interference model is compared with that of the Miner accumulated damage model based on Monte Carlo simulation. The comparison result verifies accuracy and efficiency of the proposed model. When logarithmic fatigue life standard deviation is varied, the damage critical value is decided by damage equivalent stress, and a high-precision and safer life prediction result can be gained.

Key words: multiple-site fatigue, fatigue life, reliability, median damage, critical value of probabilistic damage, Monte Carlo simulation

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