稳态温度场下整体叶盘固有特性分析

Analysis of Natural Characteristics of Blisk Under Steady Temperature Field

为了研究稳态温度场下处于高转速工作状态下整体叶盘的振动特性,根据相关参数建立全尺寸整体叶盘模型,并利用有限元方法对稳态温度场作用下的整体叶盘结构振动特性进行相关分析.在此基础上利用一维插值法赋予整体叶盘各个部分贴近实际工作状态下的温度值,最后通过有限元计算得到稳态温度场下整体叶盘的固有频率和振型分布特征.结果表明:在转速一定的情况下,整体叶盘表现出三种振动类型,包括弯曲振动、耦合振动、扭转振动.利用插值法设置的稳态温度场分析得到的叶盘固有频率较20℃荷载温度下得到的数值略有下降,下降频率为0.04%~2.33%.就下降幅度而言,一阶较为明显,二阶、三阶其次,四阶不明显;随着阶次的升高,固有频率值降低幅度减小.为设计航空发动机提供了一定的参考.

In order to study the vibration characteristics of Blisk at high speed under steady temperature field,a full-scale blisk model was established according to the relevant parameters,and the vibration characteristics of Blisk under steady-state temperature field were analyzed by finite element method.On this basis,the one-dimensional interpolation method is used to give the temperature value to each part of Blisk that are close to the actual working state.Finally,the distribution characteristics of natural frequency and vibration mode of Blisk under steady-state temperature field are obtained by finite element calculation.The results show that there are three vibration types of blisk,including bending vibration,coupling vibration and torsional vibration.The natural frequency value obtained from the steady-state temperature field analysis using interpolation method slightly decreases compared to the value obtained under a load temperature of 20℃,with a decrease frequency between 0.04%and 2.33%.For the decreasing range,the first order is more obvious,followed by the second order and third orders,and the fourth order is not obvious.With the increase of the order,the natural frequency value decreases.This paper provides a reference for the design of aero-engine.