基于缸盖振动速度识别柴油机燃烧始点的研究

Combustion Timing Identification Based on Surface Vibration Velocity of Engine Cylinder Head

建立了195柴油机机体、缸盖有限元模型,利用该模型分析了缸盖表面振动速度信号与缸内压力升高率之间的关系,认为缸内峰值压力出现之前,缸盖振动速度信号和压力升高率有相似的变化规律,可以利用缸盖振动速度信号估计柴油机的燃烧始点。利用195柴油机进行了台架试验,测量了不同工况下的缸内压力信号和缸盖振动速度信号,利用这两种信号分别对燃烧始点进行了分析,结果表明:基于缸盖振动速度信号识别燃烧始点是可行的,误差在±1°CA之间。

A finite element model for cylinder block and head of model 195 diesel engine was established and used to analyze the correlation between cylinder head surface vibration velocity and cylinder pressure rise rate. It was found that the both had similar behavior before the peak pressure occurring. So it was derived that the combustion timing may be identified by the former. Signals of the cylinder head surface vibration velocity and the cylinder pressure rise rate in different operation conditions measured in the engine bench test were used to determine the combustion timing. The results indicate that the combustion timing may be identified based on the cylinder head surface vibration velocity signals, and the deviation is within ±1°CA.