基于热机械耦合的航空发动机复材叶片疲劳寿命预测与设计参数优化

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中图分类号：TP392 文献标志码：A

Abstract： In order to achieve accurate prediction of fatigue life of composite blades for aircraft engines and optimization of blade mold design parameters，a blade mold design parameter optimization method based on thermo mechanical coupling fatigue life prediction is proposed. Construct a finite element model of engine composite blades using ANSYS Workbench，and calculate their centrifugal force，aerodynamic force，and thermal stress under thermo mechanical coupling；Then， based on the Manson Halford model，combined with the fatigue damage behavior of composite materials at different stress levels，the fatigue life of engine composite blades is accurately predicted; Finally，based on the predicted results， the NSGAI algorithm is used to optimize the mold forming parameters， thereby achieving model correction. The results indicate that the improved M-H model is closer to the 1. 5-fold error line in predicting the fatigue life of blades，proving that its prediction error is lower than that of the Morrow model， SWT model，and T-K model，and its prediction accuracy is higher. After optimizing the mold parameters， the maximum tensile stress of the composite blade decreased by 7.33% and the quality improved by 9.34% . Overall，this method can improve prediction accuracy and provide data support for subsequent optimization of mold forming parameters.

Key words： thermomechanical coupling； composite engine blade； fatigue life prediction;parameter optimization;NSGA- I algorithm

0 引言

复材叶片作为航空发动机中的核心部件，长期承受高温、高压和高速燃气工况的冲击，同时，自身旋转增加了较大的低频离心力，导致发动机中的复材叶片所受载荷存在较大的多变性和不确定性，对航空发动机的正常运行造成了极大的威胁。（剩余9194字）