Finite Element Model Updating of the Mount Bracket Based on Modal Test
2022-01-0360
03/29/2022
- Content
- The mount bracket is an important part of t he mount system, its dynamic characteristics will affect dynamic characteristics of the mount system, and then affect NVH of the vehicle. Based on the large error between the test result and the finite element analysis（FEA） result, the dynamic finite element model of the mount bracket is revised from the material parameters of the bracket and the equivalent boundary of the bolt joint. This paper presents a method to identify the parameters of the mount bracket model by combining modal test, FEA and the mathematical optimization model. Firstly,based on HyperStudy platform, the optimization objective is minimizing the natural frequency error between FEA and free mode test, and the material parameters of the bracket to be identified are used as design variables to build the optimization function. The global response surface method is used for iteration to complete the identification. Then, considering the important influence of dynamic characteristic parameters of bolt joints of the mount bracket on the test results under constrained conditions,an equivalent model of bolt joint stiffness characteristics is established by using spring elements.Again,based on the equivalent model and the parameter identification method, the optimization objective is minimizing the natural frequency error between FEA and modal test under constrained conditions ,and the stiffness parameters of spring elements are identified by iterative optimization to finish the modification of the mount bracket boundary model.At last,the modified finite element model is applied to the dynamic characteristics analysis of two different mount brackets. The results show that the maximum error of natural frequency between the calculated value and the test value is 3.03%, which indicates that the modified model has a good prediction accuracy and engineering application.
- Citation
- Kang, Y., Lu, G., Shen, D., and Shangguan, W., "Finite Element Model Updating of the Mount Bracket Based on Modal Test," SAE Technical Paper 2022-01-0360, 2022, .