随机振动载荷下发射装置尾罩疲劳寿命分析

摘要

For the problem of fatigue failure on launcher trail cover in random vibration test , the ran-dom vibration fatigue life is estimated by finite element method .The stress transfer function is obtained by frequency response simulation .Combined with S-N curve of 5 A06 aluminium alloy and acceleration power spectral density loads , random vibration fatigue life of trail cover is analyzed by Dirlik method .The results meet the requirements of random vibration test .%针对发射装置尾罩在随机振动试验中可能存在的疲劳破坏问题，采用有限元法对其随机振动疲劳寿命进行了预计。分析了频率响应，得到结构的应力传递函数。结合5 A06铝合金的S－N曲线和加速度PSD激励，采用Dirlik法计算了尾罩随机振动疲劳寿命，结果满足随机振动试验的考核要求。