汽油机爆震强度的分析

分析了汽油机缸内气体爆震燃烧压力的频率特性并推导了爆震压力共振频率计算公式。研究表明：在爆震工况下，缸内压力在高频域中有几个共振峰，峰的大小表明了汽油机爆震强度。汽油机的表面振动在这些共振频率峰处也出现相应振动峰。表面振动峰与缸力压内峰值近似成正比。汽油机表面振动峰值可作为爆震强度的评价指标，该结论在ＣＡ１１０２汽油机上得到了证实。

Analysis of the Knock Intensity in Gasoline Engines

The characteristic of knock pressure is analyzed, and the formula of resonance frequencies of knock pressure is derived. Results show that there are several resonance peaks of cylinder pressure in the range of high frequency in knock conditions. The levels of the peak represent the knock intensity in gasoline engines, and there are corresponding peaks of vibration on surface of engine for these resonance frequencies. The experimental results also show that the peak values of vibration on surface in gasoline engines are proportional to that of cylinder pressure. Therefore, vibration peak values on the surface of engine in high frequency range can be considered as the evaluation index of knock intensity, which is verified by experiment on CA1102 gasoline engine.