HCCI汽油机缸内热力学状态的影响因素

Main Influence Factors of In-Cylinder Thermodynamic State in HCCI Gasoline Engine

缸内热力学状态对汽油机HCCI着火及燃烧过程有着决定性的影响.本文在全可变气门机构单缸试验发动机上,系统研究了残余废气率、有效压缩比、空燃比、进气温度、冷却水温、进气流态以及发动机转速等参数对缸内热力学状态的影响规律.研究发现,在较大区域改变内部残余废气率时,HCCI燃烧存在热状态自稳定效应.内部残余废气、冷却水温、进气温度、空燃比、有效压缩比都可以作为控制HCCI燃烧缸内热力学状态的参数.通过对内部残余废气率、有效压缩比以及空燃比的协同管理,可以实现对缸热力学状态的快速管理,进而实现对汽油机HCCI燃烧相位的控制.

In-cylinder thermodynamic state dominates the ignition and combustion process of the HCCI gasoline engine. Based on single-cylinder HCCI engine with 4-variable valve actuation system （ 4VVAS ）, influences of internal residual rate, effective compression ratio, air-fuel ratio, intake temperature, coolant temperature, in-air flow state, and engine speed, etc. on the thermodynamic state were investigated in this paper. The result shows that thermodynamic state self-stabilization effect exists in HCCI combustion when internal residual rate is considerably altered in a larger region; internal residual rate, effective compression ratio, air-fuel ratio, intake temperature, and coolant temperature can be used as the control parameters of the HCCI in-cylinder thermodynamic-state; rapid management of in-cylinder thermodynamic state can be realized through the cooperating-management of the internal residual rate, effective compression ratio, and air-fuel ratio, based on which phase control of the gasoline HCCI combustion can be achieved.