【摘要】 采用一部分二甲醚(DME)燃料在发动机进气管与空气预先混合形成均质混合气进入气缸,另一部分DME在压缩行程末期利用压燃式发动机的燃油喷射装置喷入燃烧室实现部分预混充量压缩着火与燃料直接喷射(PCCI-DI)燃烧,开展了燃烧与供油系统参数对DME PCCI-DI发动机热效率影响的试验研究.结果表明:在DME进气引导量为每循环31.6 mg的条件下,采用5孔、0.32 mm的喷油嘴,16 MPa的启喷压力,较低的涡流比和推迟喷油,可改善TY1100 DME PC-CI-DI发动机的热效率,使发动机在较宽广的转速和负荷范围内稳定运转.更多还原

【Abstract】 Partially premixed charge compression ignition-direct injection(PCCI-DI)combustion can be realized by the way in which the partial homogeneous mixture composed of the pilot dimethyl ether(DME) and air enters the cylinder through the intake pipe and other DME fuel is directly injected into the cylinder with fuel injection equipment of the CI engine at the terminal stage of a compression stroke.Experiment investigation on parameters of a combustion and fuel system on the brake thermal efficiency of a DME engine at the PCCI-DI mode was performed.The results show that with a DME pilot quantity of 31.6 mg per cycle,a 5 0.32 mm nozzle,a 16 MPa nozzle opening pressure,a lower swirl ratio and a retarded fuel delivery advance angle,the brake thermal efficiency of the TY1100 PCCI-DI DME engine could be improved and the engine could operate at a wider range of speed and load.更多还原