针对MD6790 客车车外噪声较大情况, 运用分别运行法和声强测量法对其进行噪声源识别和噪声产生机理研究, 并在此基础上采取具有针对性的降噪措施, 使之车外加速噪声有了显著下降, 达到了国标GB 1495—2002 现阶段限值的要求。关键词: 客车; 车外加速噪声; 声源识别Abstract:A ccording to the situation that the noise em itted by acceleratingMD6790 coach is too h igh, the paper uses parts2work ing measurement and phonometry to identify the noise sources, and to study its generation mechanism. Based on th is, some step s are adop ted to reduce the noise. The noise declines remarkably and accordsw ith the lim its I of GB 1495—2002 at last.Key words: Coach; Noise em itted by accelerating motor veh icle; Identification of noise source