某涡轮叶片热-机械疲劳寿命预测与试验验证

为了得到某燃气轮机涡轮叶片关键截面的真实寿命，设计并开展了涡轮叶片热-机械疲劳试验，获得了真实寿命数据，并基于试验结果提出了一种涡轮叶片低周疲劳与蠕变疲劳交互的寿命预测方法。首先，采用一维线弹性关系、修正公式以及循环应力应变关系3种名义应力应变处理模型计算获得了名义应变；然后，利用SWT寿命关系式预测模型预测了叶片的热-机械疲劳寿命；再将预测寿命与试验获得的真实寿命进行对比分析。研究表明：对于某型燃气轮机涡轮叶片，基于SWT预测模型的循环应力应变关系方法相比于一维线弹性关系和修正公式法预测精度最高，与试验寿命相比，预测误差在4倍分散带之内。

Thermo-mechanical Fatigue Life Prediction and Test Verification of Turbine Blade

In order to obtain the real life of the key section of a gas turbine blade, the thermo mechanical fatigue test of turbine blade was designed and carried out, and the real life data was obtained.Based on the test results, a life prediction method for the interaction of low cycle fatigue and creep fatigue of turbine of turbine blade was proposed.Firstly, the nominal strain was obtained by using three nominal stress strain processing models,such as the one dimensional linear elastic relationship,the modified formula and the cyclic stress strain relationship;then, the thermo mechanical fatigue life of the blade was predicted by SWT life relation;finally,the predicted life was compared with the real life obtained from the test.The research shows that for a gas turbine blade,the prediction accuracy of the cyclic stress strain relationship method based on SWT life relation is the highest compared with the one dimensional linear elastic relationship and the modified formula method, and the prediction error is within 4 times of the dispersion band compared with the test life.