枞树形榫结构参数对应力的影响  

Effects of Structure Parameters on Firtree Tenon-mortise Stress

作　　者：余嘉伟 甘阳 杨旭峰 朱海燕 汪全中 申诗典 艾兴 杨秦政 YU Jia-wei;GAN Yang;YANG Xu-feng;ZHU Hai-yan;WANG Quan-zhong;SHEN Shi-dian;AI Xing;YANG QIN-zheng(Hunan Aviation Powerplant Research Institute,Aero Engine Corporation of China,Hunan Zhuzhou 412002,China;School of Aircraft Engineering,Nanchang Hangkong University,Nanchang 330063,China)

机构地区：[1]中国航空发动机集团有限公司湖南动力机械研究所,湖南株洲412002 [2]南昌航空大学飞行器工程学院,南昌330063

出　　处：《失效分析与预防》2024年第3期158-165,共8页Failure Analysis and Prevention

基　　金：国家重大科技专项(J2019-IV-0008-0076)。

摘　　要：航空发动机枞树形榫结构在工作时的应力状态较复杂,容易发生疲劳破坏。本文通过有限元分析研究拉削角、楔形角、接触长度对榫结构应力的影响,为榫结构的设计和优化提供参考。根据四齿枞树形榫结构的几何特点,提取典型设计参数建立枞树形榫结构的参数化模型;考虑榫结构在实际工作中的受载形式及温度的影响,采用三维接触分析方法建立枞树榫结构热-力耦合分析流程;通过调整拉削角、楔形角和接触线长度的取值,计算榫齿接触区域应力分布情况,得到各设计参量对结构应力的影响规律。结果表明:拉削角增大会导致榫槽局部应力集中加剧以及榫头两侧榫齿应力差值增大,楔形角增大会导致榫头榫槽承担的应力载荷增加,接触长度增大会导致接触应力减小;航空发动机枞树形榫结构在设计时,拉削角在20°以下,楔形角18°、20°为宜,接触长度应适当增大。Fatigue failure caused by complicated stress in aeroengine firtree tenon-mortise is a common occurrence.The impacts on structure stress from the design parameters such as skew angle,wedged angle,and contact length,were studied by finite element analysis.This study provides a valuable reference for the design and optimization of firtree tenon-mortise.According to the geometrical characteristics of the four-teeth firtree tenon-mortise structure,some typical parameters are extracted,and a parametric modeling method of the firtree tenon-mortise structure is proposed.Taking into account the loaded modes and temperature effects on the tenon structure in practice,a thermo-structural coupling flow analysis of the firtree tenon-mortise structure is established by using the three-dimensional contact analysis.By changing the skew angle,wedged angle,and contact length,the stress distribution in the contact zone is calculated and the impact of each design parameter on structural stress is analyzed.The results show that increasing the skew angle leads to the higher local stress concentration in the mortise and the stress difference between the two sides of the tenon.An increased wedge angle results in the increase of stress load on the tenon-mortise,while the increaseed contact length will lead to the decreased contact stress.During the design process in aeroengine firtree tenon-mortise,it is recommended to keep the skew angle should below 20°,maintain a wedged angle between 18°to 20°,and adjust the contact length in an appropriate way.

关 键 词：枞树形 榫头-榫槽结构 参数化建模 接触应力 热-力耦合分析 

分 类 号：V231.9[航空宇航科学与技术—航空宇航推进理论与工程]