关键词: 动力机械工程, 甲醇发动机, 冷起动, 环境温度, 循环控制, 进气预热

Abstract: The effects of the ambient temperature on the cold start behavior and the HC emission of an electronically controlled inlet port methanol injection S.I.engine were investigated by means of the single-cycle fuel injection strategy.The results show that the ambient temperature affects significantly the start firing behavior of the engine.When the ambient temperature is below 16 ℃,the methanol engine can not be started without the auxiliary startaids even at high single cycle methanol injection.Using a glowplug to heat the engine inlet manifold and additional LPG injected into the inlet port result in a reliable firing of the engine,and the ideal concept of “next cycle combustion after fuel injection” may be realized at the cold start.The ambient temperature is closely related to the fuel vaporization and fuelair mixture formation, especially at the cold start.The methanol injection amount per cycle sufficient for the reliable firing during the cold start of the engine reduces obviously and the cold start performance improves significantly with a rise in ambient temperature.

Key words: power machinery and engineering, methanol engine, cold start, ambient temperature, cyclebycycle control, inlet preheating