中文摘要：

在一台电控单体泵增压中冷发动机上,研究在固定柴油和甲醇供给时刻和供给量条件下,进气温度变化对柴油甲醇二元燃料燃烧特性的影响.结果表明：相同工况下,进气温度从40,℃变化到70,℃可以使爆发压力相差4,MPa,着火时刻相差15°,CA;进气温度的升高,不仅会造成滞燃期缩短、最大爆发压力和压力升高率增大,而且最大爆发压力出现的时刻变早、燃烧相位前移;在部分工况,变化进气温度还伴随燃烧模式的转变.温度变化还表现出柴油甲醇二元燃料燃烧和发动机转速的极大关联：在低速、较大负荷时,进气温度升高会导致输出扭矩下降和当量比油耗升高;在高速时,进气温度升高能提高输出扭矩并降低当量比油耗,但过高的进气温度会使大量甲醇在上止点之前燃烧,降低输出扭矩并提高当量比油耗.进气温度对碳烟排放也有较大影响：随进气温度降低,碳烟排放降低.综合研究结果表明,柴油甲醇二元燃料燃烧进气温度控制在50~70,℃时,可以获得最佳的经济和排放性能.

英文摘要：

Effect of intake air temperature on combustion and soot emission of a compression ignition engine operated on diesel-methanol dual fuel（DMDF）was investigated. The results show that increasing the intake air temperature would increase peak pressure and shorten the ignition delay. The centre of the premixed heat release curve was closer to the top-dead-center with the increase of the intake air temperature. For a specific operation point,the brake pres-sure increased by 4,MPa and ignition was delayed by15＆#176;,CA with intake air temperature changes from 40,℃ to 70,℃. The engine power and specific fuel consumption experienced a slight variation with the increase of the intake tempera-ture. The specific fuel consumption decreased and the output torque increased with the increase of the intake air tem-perature at high speed. The specific fuel consumption increased and the output torque decreased with the increase of intake air temperature at low speed and high load. This would be due to the change of combustion characteristics. The soot emission decreased with the decreasing of intake air temperature. It is proved that DMDF holds the best combus-tion and emission characteristics when the intake air temperature is fixed between 50—70℃.