Effects of Fuel Properties on Combustion and Exhaust Emissions of Homogeneous Charge Compression Ignition (HCCI) Engine 2004-01-1966
Homogeneous Charge Compression Ignition (HCCI) is effective for the simultaneous reduction of soot and NOx emissions from diesel engine. In general, high octane number and volatility fuels (gasoline components or gaseous fuels) are used for HCCI operation, because very lean mixture must be formed during ignition delay of the fuel. However, it is necessary to improve fuel injection systems, when these fuels are used in diesel engine.
The purpose of the present study is the achievement of HCCI combustion in DI diesel engine without the large-scale improvements of engine components. Various high octane number fuels are mixed with diesel fuel as a base fuel, and the mixed fuels are directly applied to DI diesel engine. At first, the cylinder pressure and heat release rate of each mixed fuel are analyzed. The ignition delay of HCCI operation decreases with an increase in the operation load, although that of conventional diesel operation does not almost varied. In addition, the mixed fuel containing much high volatility fuel produces the higher peak of heat release rate of premixed combustion.
The exhaust emissions (CO, CO2, THC, NOx, PM) in case of each mixed fuel are measured. Low NOx emission can be achieved by HCCI operation using the mixed fuels despite low volatility of base fuel. However, PM emission is relatively high in case of HCCI operation, and then PM is separated into SOF and ISOF. As a result, it can be confirmed that the high PM emission is derived from the increase in SOF, and the high SOF emission results from the base fuel in the mixed fuels.
Citation: Kawano, D., Naito, H., Suzuki, H., Ishii, H. et al., "Effects of Fuel Properties on Combustion and Exhaust Emissions of Homogeneous Charge Compression Ignition (HCCI) Engine," SAE Technical Paper 2004-01-1966, 2004, https://doi.org/10.4271/2004-01-1966. Download Citation