• Transactions of the Korean Society of Automotive Engineers
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• v.4 no.4
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• pp.58-71
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• 1996

A model which calculates the hydrocarbon emissions from spark ignition engines is presented The model contains the formation of HC emissions due to both crevices around piston ring top land and oil films on the cylinder wall. The model also considers in-cylinder oxidation and exhaust port oxidation of desorbed HC from crevices and oil films after combustion process. The HC emissions model utilizes the results of SI engine cycle simulation. The model predicts well the trends of HC emissions from the engines when varying engine parameters.

• Transactions of the Korean Society of Automotive Engineers
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• v.5 no.5
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• pp.114-122
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• 1997

Nowadays, gasoline direct injection engines are being commercialized by virtue of improvement in control technology of spray, flow, air fuel ratio. The stratified charge type has the advantage of improving lean limit. The homogeneous type has the advantage of reducing engine-out hydrocabon emissions in the first 30 seconds after a cold start, in addition, improving transient air fuel ratio control. The vaporization and mixing if injected fuel with air has to e completed in a short time and the fuel film in cylinder and on piston has to be minimized. So, the flow and injection should be well controlled. This paper surveyed the spray characteristics of gasoline direct injection by using laser equipment and the combustion characteristics of the single cylinder engine using homogeneousas-mixture type gasoline direct injection.