柴油机噪声源的识别研究

论述了柴油机噪声源识别的几种方法及识别结果。在噪声源识别上，采用部分缸熄火的方法对机械噪声和燃烧噪声进行了分离，发现：高转速时机械噪声是降噪重点；而在高负荷情况下，首要的是降低燃烧噪声。在表面辐射噪声源的识别上，利用表面振动法和近场声压扫描的方法进行研究，发现油底壳和缸盖罩等薄壁件是噪声的主要辐射部件，是降噪的重点。

Study of Diesel Engine Noise Source Identification

This paper presents some methods that were adopted to identify noise sources and results of the identification. The noise source identification is essential for making noise reduction strategies. The author adopted partial cylinder misfire analysis to separate machinery noise and combustion noise, the result shows that it is primary to reduce machinery noise for exciting source reduction at high speeds and to reduce combustion noise at heavy loads. The radiated noise sources were identified with the surface vibration technique and near field scan technique. Through experiment, the noise sources were identified as some cover components, such as oil pan and valve cover. It was a key point of noise reduction to restrain such components radiating noise.