涡轮叶片高温低循环疲劳/蠕变寿命试验评定

Experimental Evaluation of High Temperature Low Cycle Fatigue/Creep Life of Turbine Blade

利用试验方法确定了某型发动机 级涡轮叶片高温低循环疲劳寿命 ,试验计入了高温蠕变的影响。为了缩短试验时间 ,按照损伤等效原则 ,确定了等效加速试验载荷谱。试验是在采用感应加热、液压加载的菲利轮试验器上进行的。采用对数正态分布和威布尔分布对试验结果进行了统计分析 ,给出了置信度为 95 %、可靠度为 99.87%的叶片安全使用寿命。

The high temperature low cycle fatigue life of the 2nd stage turbine blade in an aircraft engine in service has been evaluated by use of the experimental method, in which the effect of the creep at high temperature has been considered. In order to shorten the test period, according to the principle of damage-equivalence, the equivalent accelerated test loading-spectrum has been determined. The test has been implemented on a test-bed in which eddy current inducted heating and hydraulic pressure driven force are applied. The test results have been analyzed statistically by use of logarithmic normal distribution and Weibull distribution, and the safe in-service life of the blade with the confidence level of 95% and the reliability of 99.87% has been determined.