航空发动机螺栓连接结构薄层单元静力学非线性模型修正

Modification of static nonlinear model of thin layer element for aeroengine bolted structure

针对于航空发动机机匣带有止口的螺栓连接结构的非线性刚度特征提出一种新的非线性模拟方法以及模型修正方法。首先提出了一种非线性薄层单元方法对螺栓连接结构的非线性刚度特征进行模拟,并对模拟结果进行评估;然后,提出一种新的双加权响应面修正方法;最后,使用该修正方法对螺栓连接结构静力学非线性模型修正:结果表明:本文建立的非线性薄层单元简化模型可以预测实际螺栓连接结构考虑止口接触面粗糙度的非线性刚度特征;提出双加权响应面修正方法修正前后的刚度误差维持在3.5%以内,验证了建模以及修正方法的可行性。

A new nonlinear simulation method and model modification method were proposed for the nonlinear stiffness characteristics of bolted structures with notches in aeroengine casings.A nonlinear thin layer element method was proposed to simulate the nonlinear stiffness characteristics of bolted structures,and the simulation results were evaluated.A new dual weighted response surface correction method was also proposed.The modified method was used to modify the static nonlinear model of bolted structures.The results showed that the simplified nonlinear thin layer element model can predict the nonlinear stiffness characteristics of actual bolted structures considering the roughness of the seam contact surface;a dual weighted response surface correction method was proposed to maintain the stiffness error within 3.5% before and after correction,verifying the feasibility of the modeling and correction method.