Host: The Japan Society of Mechanical Engineers
Name : [in Japanese]
Date : March 19, 2025 - March 20, 2025
To realize a super-leanburn SI engine with a very-high compression ratio, it is required to design a new fuel which could have low ignitability at a low temperature for antiknocking, but high ignitability at a high temperature for combustion stability. Ethane shows a long ignition delay time at a low temperature close to that of methane, but a short ignition delay time at a high temperature close to that of gasoline. Ethane addition to gasoline could be a good example of fuel design to improve both combustion stability and antiknocking property. In a previous study, methane, ethane, or propane with the RON of 120, 115, or 112, respectively, was added to a gasoline surrogate fuel with the RON of 90. The ethane or propane addition advances CA10, resulting in the shortening of combustion duration. Any addition advances knocking limit. The advance of knocking limit is larger in the order of ethane addition > propane addition > methane addition, which is dependent on not the RON of the gaseous fuel, but the rate of OH consumption by the gaseous fuel. In the present study, methane, ethane, or propane has been added to a PRF with the RON of 90, 95, or 100, or toluene with the RON of 120, with the energy fraction of the gaseous fuel of 0.15, 0.25, or 0.35. For the addition to PRF90 or PRF 95, the advance of knocking limit is larger in the order of ethane addition > propane addition > methane addition. Any addition to toluene retards knocking limit. The retard of knocking limit is larger in the order of propane addition > ethane addition > methane addition, which is dependent on the RON of the gaseous fuel.
