结构有限元模型修正的频响函数方法

在将结构有限元模型的修正量表示为子结构的误差因子的线性函数的基础上,导出了一种利用试验频响函数修正有限元模型的质量、刚度和阻尼矩阵的方法。为减少大型复杂结构有限元模型修正的计算量,使用改进缩聚系统(IRS)方法缩减模型的自由度。该方法可以在结构振动试验的测量自由度小于模型自由度的情况下得到模型修正量,并使修正后的模型保持原有的自由度和稀疏特性。

The Frequency Response Function Method for Updating Structural Finite Element Model

Based on the improvement volume of structural Finite Element model is expressed as linear functionsof the error factors of substructures,a method for updating the mass,stiffness and damping matrices ofstructural Finite Element model using the experimental frequency response functions is given.In order todecrease the capacity of computation for improvement process of large structural Finite Element model,thenumber of degrees of freedom of model are reduced using the procedure for Improved Reduced System(IRS)model.This method may obtain the improvement volume of model when the measured number of de-grees of freedom in the structure vibration test are less than the model's one,and enables the improvedmodel to keep original number of degrees of freedom and sparse characterstics.