Combustion Technology Development for a High Compression Ratio Gasoline Engine

Abstract

Internal combustion engines still play a vital role in realizing the low carbon society. For spark ignition engines, further improvement in thermal efficiency can be achieved by increasing both compression and specific heat ratios. In the current work, the authors developed practical technologies to prevent output power loss due to knocking at full load, which is a critical issue for increasing compression ratio. The results show that a significant increase in compression ratio and improvement in thermal efficiency at part load are achieved by using these new technologies.