基于热固耦合预应力的发动机叶片模态分析方法  

Modal Analysis of Aero-engine Blade Based on Thermal-structure Coupling Pre-stressing Force

作　　者：李春旺[1] 王澈[2] 李强[1] 武晓亮[1] 张忠平[1] 

机构地区：[1]空军工程大学理学院,西安710051 [2]空军工程大学装备管理与安全工程学院,西安710051

出　　处：《空军工程大学学报（自然科学版）》2016年第2期1-4,共4页Journal of Air Force Engineering University(Natural Science Edition)

基　　金：国家自然科学基金(5157552);陕西省自然科学基金(2015JM5240);空军工程大学理学院博士(后)基金(2013BSKYQD09)

摘　　要：发动机叶片在工作环境中承受着热载荷、离心载荷和气动载荷的共同作用,导致材料的机械性能发生变化,使得发动机叶片振动频率及形态与室温静止状态有所不同。为了综合考虑各种因素的共同影响,准确分析发动机叶片在实际工作状态下的固有振动频率及振型,运用有限元分析软件ANSYS,由热分析得到叶片的温度场,并将其耦合到结构分析单元,进行结构分析得到叶身的热应力分布后,施加离心载荷与气动载荷,对叶片进行重启动分析,得到叶片的综合应力分布,并以此为预应力对叶片进行模态分析,计算叶片工作状态下的固有振动频率及振型。分析中综合考虑了温度场及应力场对叶片模态的影响,找到了基于热固耦合预应力的发动机叶片模态分析方法。Aero-engine blades bear the common act of thermal load, centrifugal load and aerodynamic load under conditions of working. These loads will not only change the mechanical performances of the blade material, but also make the natural frequency and mode shapes of the blade different from the stationary ones at room temperature. All the factors are considered accurately by using finite elements analysis （FEA） software ANSYS during modal analysis. The working temperature of blades is obtained from thermal analysis first, and then is coupled to structure elements to calculate the thermal stress of the blade by using structural analysis. After obtaining the thermal stress, the FEA is restarted by applying centrifugal load and aerodynamic load to study multiple stresses of the blade. At last, taking the multiple stresses as pre-stressing force, natural frequency and mode shapes of the blade are analyzed under conditions of work- ing. The paper synthesizes both temperature and stress influence on blade modal, and a modal analysis method of aero-engine blade is obtained based on thermal-structure coupling pre-stressing force. And this method has an important theoretical meaning and engineering practical value.

关 键 词：发动机叶片 热固耦合 预应力 模态分析 

分 类 号：V235.1[航空宇航科学与技术—航空宇航推进理论与工程]