阻尼处理降低重型卡车驾驶室低频噪声

摘要

A low-frequency noise control method based on modal analysis is proposed. It is applied to a heavy duty truck which has serious booming noise in the cab in idle state. Firstly, the frequency information of the interior noise is obtained through noise testing and FFT analysis. Then the modal analysis of the white-body of the cab is carried out to determine the positions of the modals near the peak noise frequency. The damping treatment is implemented in these positions to reduce the structure-borne noise. Finally, the noise test of the truck after the treatment is carried out to evaluate the effect of this method. The test results show that the peak noise value of the main frequency is reduced by 5.4 dB(A)-7.5 dB(A). Therefore, the low-frequency noise of the cab is controlled successfully.%提出一种基于模态分析的重卡驾驶室低频噪声控制方法，将其应用于一款在怠速工况下低频轰鸣噪声较严重的重型卡车上。首先对车内噪声的频谱特性进行测试分析，获取低频噪声的频率成分信息。然后对驾驶室白车身进行模态分析，确定噪声峰值频率与车身结构振动关系，并对该部位采用阻尼处理以降低结构辐射噪声。对处理后的试验车进行噪声评价测试，结果表明主要频率处的噪声峰值降低了5.4 dB(A)～7.5 dB(A)，试验车驾驶室低频噪声得到有效控制。