发动机台架试验的排气系共振及对噪声的影响

Exhaust System Resonance on Engine Bench Testing and Its Effect on Engine Noise

内燃机排气系噪声试验中,在某种转速下,排气系发生共振,从而使发动机噪声大大增加。本文通过对比试验分析了两种管长在不同转速下噪声频谱图,其共振转速与计算结果比较吻合。文中还比较了用发动机转速慢加速扫描的动态方法及稳态转速下测得的噪声值。

In concurrence with the exhaust system resonance occurs at certain engine rotating speed during testing, the noise level of engine will substantially increase. The analysis of noise spectra of two exhaust pipes at different engine speeds is made. the resonance speed is obtained and agrees with the calculating value. The noise values measured by using gradual acceleration scanning and steady engine speed methods are also compared in this paper.