中文摘要：

综合运用声强法、消去法和选择性声强法进行摩托车怠速异响噪声源识别试验,分析异响的产生机理及传播途径,结果表明：异响的频率范围为891～2239Hz,排气消声器隔热板辐射噪声是主要噪声源,排气气流冲击消声器内部隔板是其根本原因。增大消声器内部隔板与壳体连接刚度能够有效消除怠速异响。

英文摘要：

Utilizing sound intensity method,source separation method and selective sound intensity method comprehensively,the abnormal noise source of motorcycle under idle condition was identified.The production mechanism and transmission of the abnormal noise was analyzed.The results show that the frequency ranges from 891Hz to 2239Hz and the radiation noise of exhaust muffler heat shield is the dominate source and the impact to the muffler internal partitions by exhaust airflow is the root reason.The abnormal noise can be eliminated effectively by strengthening the connection stiffness of the muffler internal partitions.