Abstract: To solve the abnormal acceleration noise of diesel vehicle, did the noise,vibration, harshness (NVH) test for the diesel vehicle. Through spectrum analysis found that the abnormal noise was the broadband noise of 2 500 Hz and 5 000 Hz. And analyzed the vibration frequency characteristics of related parts, found that the cooling system of the supercharger was the main propagation path. Optimized the cooling tube by adding a muffler, and obtain a great effect. The validation show that the broadband noise of 2 500 Hz and 5 000 Hz decrease respectively 5 dB(A) and 10 dB(A) and the abnormal noise remove. The result show that the noise will be improved by optimizing the structural parameters of silencer.

Key words: Diesel vehicle; Abnormal noise; Spectrum analysis; Silencer

摘要： 为解决某柴油车加速异常噪声问题，对该柴油车进行噪声、振动与声振粗糙度（NVH） 试验测试。通过频谱分析发现加速异常噪声主要表现为 2 500 Hz、5 000 Hz 附近的宽频噪声； 通过分析相关零部件的振动频率特征，得到异常噪声主要通过中冷系统的管路传播。在左侧 中冷管增加多腔穿孔型宽频消声器，并通过主观评价与客观测试验证。试验对比显示，优化 改进后，2 500 Hz、5 000 Hz 宽频段噪声分别降低了 5 dB(A)、10 dB(A)，异常噪声消除。结 果表明，优化消音元件结构参数，改变消音孔穿孔率，可以改善车辆的噪声结果。

关键词: 柴油车；异常噪声；频谱分析；消音元件