基于缺陷失效仿真路径压力容器的安全裕度与剩余寿命研究

针对目前难以准确获得压力容器缺陷裂纹临界值aN的状况,通过基于空气动力压力容器安全评定的缺陷失效路径与失效速率的仿真系统,来寻找裂纹缺陷在安全临界域速率拐点及准确获取aN的临界值的计算方法。反映缺陷"安全裕度"的射线法或平行线法并不能反映缺陷真实的动态安全程度,而应该是沿着缺陷的失效路径来进行标定缺陷趋近安全临界线的距离,而这个距离真实反映了缺陷的剩余循环疲劳次数,进而建立一种全新的评估压力容器剩余寿命的理论判据。

Study on the Residual Life and the Safety Margin of Pressure Vessel Based on the Defect Failure Simulation Path

It is difficult to obtain critical values of pressure vessel defect cracks accurately , using the safety evaluation simulation system for the failure rate and paths of the crack on the aerodynamic pressure vessel to find the inflection point of the failure rate in safety critical region and the threshold. The ray method or parallel method do not reflect the real level of dynamic security, but the defects along the failure path which reaches safety critical distance and this distance really reflect the remaining number of cyclic fatigue defects, and a new theory criterion for pressure vessel residual life prediction is established.