MATHEMATICAL MODELING OF HC EMISSIONS RELEASED by OIL FILM for GASOLINE and GASEOUS FUELS

Abstract

Oil film on cylinder liner has been suggested as a major source of engine-out hydrocarbon emissions. In this study, a mathematical modeling for the rate of absorption/desorption of the fuel in the oil film has been developed for gasoline, LPG and methane. It was seen that the absorption/desorption mechanism of LPG and methane into the oil film were lower than gasoline. It was determined that the most dominant parameter of this difference was Henry's constant, which was related to solubility. As interaction time of oil film-fuel vapor was longer at low engine speeds, the quantities of HC absorbed/desorbed increased. The quantities of HC absorbed/desorbed increased with increasing inlet pressure and compression ratio.