Research On Vibration And Noise Reduction Technology Of A Type Of Off - Road Vehicle Cab

With the automotive industry rapidly growth in our country, heavy off-road vehicles are becoming more and more concentrated by the relevant manufacturers. Moreover, customers’ requirements for performance of heavy off-road vehicle, particularly the NVH performance. The cab vibration caused by road roughness is the main source of low frequency interior noise. Therefore, in order to reduce the vibration, it’s essential to take research on the vibration characteristics.This paper is based on the analysis of vibration and noise control from both here and abroad. The vibration characteristics and acoustic characteristics of a cab system are processed. And the optimization design theory is applied to optimize the cab structural focusing on some sensitive frequency, along with panel acoustic contribution analysis.According to the analysis result, the modal parameters of the cab system, from the experimental modal analysis of the BIW, and the analysis result from theory modal analysis on the base of cab FE model built, Take validation and verification of the FE model. Then carry out the heavy off-road vehicle road test, record the corresponding connecting point of the vehicle body signal. Take the processing signal under pre-analysis and dynamic post processing as the excitation load to calculate the frequency response analysis, figure out sensitive frequency and panels with large vibration analysis the result of the inside and corresponding reasons.Panel contribution analysis is based on frequency response analysis results, analysis and compare all acoustic panel contribution factors to obtain one panel as optimization object. On the basis of above, a composite structure with free damping layer is set up as the renew panel selected, take topology optimization to get the optimal structural and re-compute frequency response so as to compare the acoustic pressure level.