低压涡轮轴改进疲劳设计方法与试验验证  

Improved fatigue design method and experimental verification of low-pressure turbine shaft

作　　者：饶云松 王学民 黎方娟 古远兴 郭建英 徐敬沛 RAO Yunsong;WANG Xuemin;LI Fangjuan;GU Yuanxing;GUO Jianying;XU Jingpei(Sichuan Gas Turbine Establishment,Aero Engine Corporation of China,Chengdu 610500,China)

机构地区：[1]中国航发四川燃气涡轮研究院,成都610500

出　　处：《航空动力学报》2025年第2期280-294,共15页Journal of Aerospace Power

基　　金：航空动力基础研究项目。

摘　　要：总结了轴高低周复合疲劳设计名义应力法的两种传统方法:大扭矩当量稳态剪应力方法和多轴等效应力方法。由于这两种传统方法存在以下适用局限性:大扭矩当量稳态剪应力方法仅适用于轴弯矩载荷可忽略的部位;多轴等效应力方法仅适用于应力集中系数可忽略的部位疲劳储备评估,不适用于疲劳寿命及累积损伤评估。参考了多份相关资料中的疲劳设计方法,提炼优点,规避缺点,提出了适用范围更广泛、理论原理更合理的轴改进疲劳设计方法,应用于某低压涡轮轴高低周复合疲劳设计,并经试验验证分析。结果表明:该改进方法计算结果与两个阶段试验现象吻合,疲劳损伤偏差为12.6%,明显好于传统方法的84.7%,满足寿命分析结果误差控制在2倍散度以内(即误差范围为−50%~100%)的通常工程要求。Two traditional methods of nominal stress method for shaft high-low cycle combined fatigue design were summarized:large torque equivalent steady-state shear stress method and multi-axis equivalent stress method.These two traditional methods have the following limitations:the large torque equivalent steady-state shear stress method is only suitable for shaft parts with negligible bending moment load;and the multi-axis equivalent stress method is only suitable for fatigue reserve evaluation of parts with negligible stress concentration coefficient,but not for fatigue life and cumulative damage evaluation.Referring to the fatigue design methods in many related books,the advantages were refined while avoiding the disadvantages,an improved fatigue design method of shaft with wider application scope and more reasonable theoretical principle was put forward,which was then applied to the high-low cycle combined fatigue design of a low-pressure turbine shaft,and also the experimental verification.The results showed that the calculation results of this improved method coincided with the phenomena of the two-stage test,and the fatigue damage deviation was 12.6%,which was significantly better than that of the traditional method(84.7%),and met the engineering needs of the life analysis results within 2 times the scattering error control(i.e.,error range:−50%—100%)of the usual requirements.

关 键 词：低压涡轮轴 高低周复合疲劳 名义应力法 有限元 疲劳寿命 累积损伤 

分 类 号：V232.2[航空宇航科学与技术—航空宇航推进理论与工程]