An accurate life prediction is important to the design of a high-speed rotary blade subjected to multilevel cyclic loads. The widely used Miner’s rule and uniaxial stress prediction method always deviate from actual life of the blade. A prediction method based on Chaboche’s nonlinear damage evolution model is utilized to predict the multilevel cyclic fatigue life of a compressor blade subjected to start-up centrifugal force and working aerodynamic force. Chaboche’s model is verified by comparing with experimental data of different materials. The blade life predicted by Chaboche’s rule and Miner’s rule are compared, and it is found that Miner’s rule might overestimate the blade life under the typical loading spectrum of start-up centrifugal force and working aerodynamic force. To study the impact of multiaxial stress state on the blade life, the life predicted by uniaxial stress method is compared to that predicted by multiaxial stress method, and it demonstrates that the multiaxial stress state of the blade should not be neglected. Finally, the crack propagation of the blade under multiaxial fatigue loads is simulated successfully by element deletion technique, which is conducted by translating Chaboche’s multiaxial model into a user defined UMAT program in ABAQUS. The predicted crack propagation life is compared with that predicted by an approximate Paris law method plate model. This research proves that the method to predict the blade life subjected to multilevel cyclic loads based on multiaxial Chaboche’s model could provide a valuable reference for engineering blade fatigue design.

中文翻译：

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一种实用的非线性损伤累积方法预测叶片在多级循环疲劳载荷下的寿命和裂纹扩展

准确的寿命预测对于承受多级循环载荷的高速旋转叶片的设计很重要。广泛使用的Miner法则和单轴应力预测方法总是偏离叶片的实际寿命。采用基于Chaboche非线性损伤演化模型的预测方法，对压缩机叶片在启动离心力和工作气动力作用下的多级循环疲劳寿命进行预测。Chaboche 的模型通过与不同材料的实验数据进行比较来验证。比较了Chaboche法则和Miner法则预测的叶片寿命，发现Miner法则可能高估了典型的启动离心力和工作气动力载荷谱下的叶片寿命。研究多轴应力状态对叶片寿命的影响，将单轴应力法预测的寿命与多轴应力法预测的寿命进行比较，表明叶片的多轴应力状态不可忽视。最后，通过将Chaboche的多轴模型转化为ABAQUS中用户定义的UMAT程序，通过单元删除技术成功模拟了叶片在多轴疲劳载荷下的裂纹扩展。将预测的裂纹扩展寿命与通过近似巴黎定律方法板模型预测的寿命进行比较。研究证明，基于多轴Chaboche模型的多级循环载荷下叶片寿命预测方法可为工程叶片疲劳设计提供有价值的参考。表明叶片的多轴应力状态不容忽视。最后，通过将Chaboche的多轴模型转化为ABAQUS中用户定义的UMAT程序，通过单元删除技术成功模拟了叶片在多轴疲劳载荷下的裂纹扩展。将预测的裂纹扩展寿命与通过近似巴黎定律方法板模型预测的寿命进行比较。研究证明，基于多轴Chaboche模型的多级循环载荷下叶片寿命预测方法可为工程叶片疲劳设计提供有价值的参考。表明叶片的多轴应力状态不容忽视。最后，通过将Chaboche的多轴模型转化为ABAQUS中用户定义的UMAT程序，通过单元删除技术成功模拟了叶片在多轴疲劳载荷下的裂纹扩展。将预测的裂纹扩展寿命与通过近似巴黎定律方法板模型预测的寿命进行比较。研究证明，基于多轴Chaboche模型的多级循环载荷下叶片寿命预测方法可为工程叶片疲劳设计提供有价值的参考。通过将Chaboche的多轴模型转化为ABAQUS中用户定义的UMAT程序，通过单元删除技术成功地模拟了叶片在多轴疲劳载荷下的裂纹扩展。将预测的裂纹扩展寿命与通过近似巴黎定律方法板模型预测的寿命进行比较。研究证明，基于多轴Chaboche模型的多级循环载荷下叶片寿命预测方法可为工程叶片疲劳设计提供有价值的参考。通过将Chaboche的多轴模型转化为ABAQUS中用户定义的UMAT程序，通过单元删除技术成功地模拟了叶片在多轴疲劳载荷下的裂纹扩展。将预测的裂纹扩展寿命与通过近似巴黎定律方法板模型预测的寿命进行比较。研究证明，基于多轴Chaboche模型的多级循环载荷下叶片寿命预测方法可为工程叶片疲劳设计提供有价值的参考。