Search Results

It is necessary to diagnose the combustion characteristic to improve the engine performance and fuel consumption. This is the reason why the many researches have been done to measure the temperature and pressure in combustion chamber. Of course, there are several methods, but they are proper only to laboratory scale not to commercial automotive due to their cost and difficulty of installation. So during the last few decades, the increasing interest and requirement for detection of combustion phenomena has led to the implementation of several different sensor technologies. This paper introduces a new method to predict the temperature of combustion chamber in vicinity of spark plug during the combustion period. A model which is utilized in this study is based on a breakdown voltage analysis, which relate the density of gas inside the combustion chamber. To verify the result of this method, it is compared with the 2-zone model of heat release rate.

Engine misfire (total or partial) causes a negative effect on the engine power and the exhaust emissions such as HC, CO and NOx. Moreover, it causes damage to the three-way-catalyst(TWC) system permanently. So, Engine misfire should be detected and eliminated. This study introduces a new system concept which is detecting combustion misfire using breakdown voltage (BDV) characteristics between electrodes. The focus of this study is that the detection and decision of misfire criterion through the misfire intensity calculation with BDV signal, which is derived by the application of a high bias voltage (30kV) to the spark-plug gap in the engine continuously. This study is driven to check the relation among BDV signal and misfire intensity inside an engine cylinder.