离子电流法在发动机燃烧室内工作过程检测中的应用

描述了一种新的发动机信号检测方法———离子电流法 ,即直接利用火花塞电极作为传感器检测汽车发动机燃烧室内工作过程信号的方法 .当发动机工作时 ,由于工况不同、燃气密度不同 ,通过火花塞离子电流的大小及变化也将不同 ,因此利用火花塞电极作为信号感受器 ,可以检测诸如缸内压力、负荷、失火等发动机信号 ;为了获得不同目的的信号检测 ,作者首次在火花塞电极两端加不同的电压 ,获得了发动机在做功冲程以及进、排气冲程中的离子电流信号 ,为今后进一步检测其它信号 ,如爆震、排放等奠定了基础 .

Ionic Current for Detecting Burning Signals in Combustion Chamber of Gasoline Engine

Spark plug is used as a probe for detecting burning signals in automobile engine. It serves as an ionic density sensor as hydrocarbon is being burned. Monitoring of ionic density is thus made possible for the flame behavior after ignition during period of engine strokes. Results are presented and discussed for a four-cylinder engine including the effects of many factors such as the polarity of bias voltage in the spark plug, relationship between cylinder pressure and load with the ionic current, ignition burn time, different voltage between the spark plug gap, etc.. Adjustments could thus be carried on for misfire and knock of internal combustion engine.