含裂纹燃气涡轮叶片结构非概率可靠性分析

涡轮叶片是燃气轮机装置中失效最频繁的工作部件,其主要的失效模式之一为裂纹扩展而引起的疲劳断裂失效。以含裂纹燃气涡轮叶片为研究对象,根据其典型启动运行工况制定载荷谱,通过瞬态热弹塑性有限元分析确定叶片失效的危险部位,并据此建立含裂纹叶片的实体模型;根据瞬态热弹塑性分析结果和J积分强度判据,对含裂纹叶片进行非概率可靠性分析。通过工程实例,验证了结构非概率可靠性综合模型的可行性和可操作性,为非完善结构的可靠性分析评定提供了新的方法体系。

Non-probabilistic Reliability Analysis of Gas TurbineBlade with Cracks

Turbine blade is the core component and vulnerable part of the gas turbine. It works in a very poor environment, and bears huge alternating stress under high temperature condition. Therefore, turbine blade is the most frequently failure component in the gas turbine and the main failure mode is fatigue failure due to crack propagation. According to the start working condition of a gas turbine, the load spectrum is worked out. The dangerous location of blade failure is determined by transient thermal elastic-plastic finite element analysis (FEA), and the solid model of cracked blade for FEA is established. According to the J integral strength criterion and the results of transient thermal elastic-plastic FEA, the non-probabilistic reliability of the cracked blade is analyzed, so a new method or way is provided for the reliability analysis of imperfect structures.