某发动机气流敲击异响试验分析及优化

Experimental Analysis And Optimization Of Intake Pulsation Noise Of An Engine

本文以某款混动车型搭载1.5L增程式发动机为研究对象,发现该混动车型在怠速充电工况下产生有节奏的"咕噜音"异响。通过对异响源进行特征频率和传递路径测试分析,确定了"咕噜音"异响来自于进气系统,为歧管前端驻波共振引起的气流敲击异响,其特征频率为"300-500Hz"。通过对进气系统的噪声频率分析优化,针对异响特征频率设计了一款排式谐振腔式的消声单元,并在发动机NVH台架上进行了优化验证试验,其进气口噪声在"300-500Hz"频段,噪声下降约7-9dB(A),解决了异响"咕噜音"的问题,取得了较好的降噪效果。

This paper takes a hybrid model equipped with a 1.5 L add-on engine as the research object,and finds that the hybrid model produces a rhythmic "grunt" sound under idle charging conditions.Through the characteristic frequency and transmission path test analysis of the iso-loud source,it is determined that the "grunt sound" noise comes from the intake system and is caused by the resonance of the front of the manifold,with a characteristic frequency of "300-500 Hz".Through the optimization of noise frequency analysis of the intake system,a row-type resonant cavity-type muffler unit is designed for the characteristics frequency of the noise,and the optimization and verification test is carried out on the engine NVH bench,and its air intake noise is in the "300-500 Hz" band,the noise drop is about 7-9 dB(A),which solves the problem of the "grunt" sound and achieves good noise reduction effect.