基于虚拟激励法的多激励振动试验数值分析

Numerical Simulation of the Multi-Input Multi-Output Random Vibration Tests Based on Pseudo Excitation Method

针对细长型飞行器双台振动试验开展仿真计算与控制效果分析。根据模态叠加原理,建立细长型飞行器多输入多输出(multi-input multi-output,MIMO)随机振动试验中的动力学模型;采用虚拟激励法和逆虚拟激励法计算方法,分析细长型飞行器MIMO随机振动试验中不同控制测点数量、控制谱矩阵设置的可实现性及影响效果,并以其模拟件为研究对象,完成其两点、多点控制试验方式下不同控制谱矩阵设置的振动试验的数值模拟。经分析,虚拟激励法大幅提升了振动仿真计算精度,且双台振动系统在不同控制点组合下振动响应差异性加大。

In this paper,the numerical simulation and control effect of double-vibration test for the slender aerocraft were studied.Using the Mode-superposition method,a dynamic model of the slender aerocraft under multi-input multioutput random vibration tests was proposed in this paper.The pseudo excitation method and inverse pseudo excitation method were adopted to study the influence of the reference point number and the reference spectral density matrix.The numerical simulation of the Multi-Input Multi-Output random vibration tests of a simulator of the slender aerocraft under different reference point numbers and reference spectral density matrices was acquired.Finally,the numerical simulation results were promoted through the pseudo excitation method,and the vibration responses of the various control point combinations were different for the double-vibration system.