关键词: 加速轰鸣；传递路径分析；模态贡献量；NVH；后背门

Abstract: A sport utility vehicle (SUV) tooling sample vehicle driving on a smooth asphalt road, there is serious acceleration booming of the driver's inner ear in the subjective evaluation when the engine speed is 2 700 r/min under the condition of third gear wide open throttle. There is a peak value in the sound pressure response curve under this condition is showed in the test results, and the second-order response is dominant. There is a corresponding peak value at 2 730 r/min in the whole vehicle acceleration simulation analysis. Through the analysis of transmission path and modal contribution, it is determined that the coupling of the middle snap mode of the tailgate and the second-order mode of the body cavity was the main reason for the acceleration booming. The tailgate mode is improved to avoid frequency with the acoustic cavity mode. The tailgate mode is the single constrained mode and the installation state of the full vehicle. Firstly, the single constrained mode is improved to find the optimization scheme, and then it is verified in the vehicle state to determine the effective and reasonable scheme. Finally, the booming peak value is reduced by 3～4 dB through the real vehicle test, meeting the established target line requirements, and the subjective evaluation is accepted. The idea of using the constrained modal optimization of the tailgate subsystem to solve the acceleration booming of the full vehicle had a certain reference significance for similar real vehicle problems.

Key words: Acceleration booming; Analysis of transmission path; Modal contribution; NVH; Tailgate