用裂纹扩展随机模型估算潜艇耐压壳体的疲劳寿命

Estimation of Fatigue Life of Submarine Pressure Hulls Using Random Model of Crack Propagation

用Paris公式预测以时间为函数的疲劳裂纹扩展,要考虑很多不确定因素,问题十分复杂。本文引用了考虑裂纹尺寸变异性的裂纹扩展随机模型,估算了潜艇的耐压壳体在不同循环次数下疲劳热点的疲劳寿命,并将结果与使用建立极限状态方程的一阶二次矩法估算的疲劳寿命进行了比较和分析。

It need take into account many uncertainty ingredients when forecasting the propagation of crack , which is the function of time by Paris' formula and this is quite complex. In this paper, the fatigue life is estimated by the random model of crack propagation at the critical point within the cone-cylinder of submarine pressure hull in load cycle and the variability of this model is considered . This result is analyzed and compared with that using FOSM(first-order second-moment) method.