Method for improving low-frequency vibration performance of complex structure

Abstract

The invention discloses a method for improving the low-frequency vibration performance of a complex structure. Firstly, a test modal analysis method is adopted to obtain a test modal and vibration frequency response function of the automobile structure, and the test system comprises a vibration exciter, a test system, a test computer, a three-way acceleration sensor and the like. Then, a finite element analysis model of the vehicle body structure is built through a finite element modeling technology, the accuracy and reliability of the model are determined through modal benchmarking analysis,and the modal and vibration frequency response function of the finite element model is calculated. For the frequency with abnormal vibration frequency response function peak value, sensitivity analysis based on the plate thickness is carried out, and the plate with the local rigidity not matched with the overall rigidity of the vehicle body design is found. According to the concentrated distribution area of the modal strain energy on the plate under the frequency, a structure optimization method is adopted, so that the problem frequency vibration peak amplitude is greatly reduced, a good effect is obtained, the product performance is improved, the research and development and manufacturing period is shortened, and the cost is reduced.

Description

technical field [0001] The invention relates to a method for finding the source of vibration for low-frequency vibration of a complex structure and an improved method. Background technique [0002] With the continuous and rapid development of my country's economy and society, the number of motor vehicles continues to maintain a rapid growth trend. According to statistics from the Ministry of Public Security, as of December 2018, the number of motor vehicles in the country reached 325 million. Cars are increasingly becoming an integral part of people's lives. People's requirements for car quality are also increasing year by year. Car NVH (Noise, Vibration, Harshness) performance is one of the important indicators to evaluate the comfort performance of a car, and it is also a key factor to measure the quality of a car. When the world-renowned product quality evaluation organization J.D. Power evaluates the quality of automobiles, nearly one-third of the quality indicators a...

AI Technical Summary

Problems solved by technology

[0004] In order to better solve the problem of low-frequency vibration of automobiles, the present invention provides a method for finding the source of vibration and improving the low-frequency vibration of complex structures

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