Study of the Technology for Low Compression Ratio in Passenger Car Diesel Engines

Abstract

The improvement in fuel consumption was kept down to a compression ratio of 14:1, because of lower friction losses. However, low compression ratio engines have issues of poor starting performance, white smoke, and combustion instability in low temperature environments or in high altitude conditions. Through this study, we managed to keep the fuel mixture temperature high. Large numbers of fuel injection nozzle holes, multi-pilots with good mixture spreading, and large diameter of combustion chamber have been evaluated as being effective countermeasures. These methods have realized a compression ratio of 14:1.