火花点火機関の排気系におけるHC濃度の経時変化に関する研究 : 第2報, ガス燃料を用いた場合の冷態始動時におけるHC濃度の経時変化とクレビス体積の影響

抄録

This paper focuses on the oxidation process of unburnt hydrocarbons from a gaseous fueled spark ignition engine under the cold starting condition. The time history of the hydrocarbons concentration and the exhaust gas temperature in the exhaust pipe have been measured experimentally. The experimental data show that the high concentration of hydrocarbons in the exhaust pipe are found during 30s after the engine has started under the cold starting condition. These results can be explained by the fact that the measured temperature of the exhaust gas under the cold starting condition is lower that that of the warmed-up condition. The concentration of hydrocarbons increase with increasing of the ring crevice volume under the warmed-up condition. On the contrary this effect is not found under the cold starting condition. Because the oxidation in the exhaust process is weak under the cold starting condition.