基于不相关模态振型的修正技术

为充分利用试验测量结果，探讨了一种修正技术，不但有效利用试验数据中与有限元模型相关的模态信息，同时也有效利用不相关模态信息，并成功应用于某型现代高推质比涡扇发动机结构中.通过计算，修正后的模型计算值与试验测试值比较接近，误差接近0，MAC（model assurance criteria）值接近1.研究表明:利用不相关模态振型的模型修正技术能够有效得到准确的修正参数值，且修正后的有限元模型具有很高的计算精度. 

Updating technology based on uncorrelated mode shapes

In order to make full use of the test measurement results, a method of FE (finite element) model updating with adoption of both correlated and uncorrelated modes for updating was put forward, and successfully applied in a certain type of modern high thrust weight ratio turbofan engine. The calculated values of the modified model were close to the test values by the correction calculation. The error was close to 0 and the MAC (model assurance criteria) value close to 1. Result showed that, the proposed method was found to successfully update an FE model yielding correct estimates of the updating parameters in the presence of uncorrelated modes, and the updated FE model had a high calculation precision.