An Energy Error Estimation Method for Improving Analytical Models Using Vibration Modal Test Data

Abstract

When improving analytical dynamic models using modal test data, correct localization of the poorly modelled areas in the analytical model is essential for ensuring the accuracy of the model improvement obtained. In this paper, a method referred to as the energy error estimation (EEE) method is proposed. Firstly, this method is capable of effectively distinguishing the correctly modelled mass and stiffness elements from those poorly modelled regions by using a limited number of test modes. This results in an accurate localization of the analytical modelling errors. Secondly, a set of correction factors can be obtained for improving those elements that are identified as having been poorly modelled. The improved analytical model will also retain its original matrix configuration, size and physical explanation, which is desirable.

In order to verify the efficiency and accuracy of this proposed method, beam examples using both simulated and experimental modal test data are demonstrated. Excellent model improvement is shown in these examples.

Keywords

analytical dynamic model modelling error localization error correction energy error estimation method vibration modal test data

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