【摘要】 基于一台单缸汽油发动机，设计了主动预燃室系统，试验了预燃室混合气状态对燃烧及排放的影响，通过对比不同点火能量的火花塞点火和预燃室点火，明确预燃室射流点火对燃烧过程影响机理．结果表明：随着预燃室内喷油量的增加，颗粒物数量(PN)排放增加；预燃室内浓混合气能改善燃烧相位、加快燃烧速度，提高点火性能，但预燃室内当量比附近的混合气有更大的节油潜力．当全局过量空气系数φglobal小于1.4时，预燃室点火燃油消耗率恶化；当φglobal大于1.4时，预燃室改善热效率的能力开始凸显．当预燃室中燃油量占总循环油量的分数为2%时，预燃室点火能将稀燃极限扩展至φglobal为2.1，在φglobal为1.8时总指示热效率达到48.5%的最大值．更多还原

【Abstract】 An active pre-chamber system was designed and the effect of the pre-chamber mixture state on combustion and emissions were experimentally studied on a single cylinder gasoline engine. The influence of pre-chamber jet ignition on combustion characteristics was also analyzed by comparison of traditional ignition with different ignition energy and the pre-chamber ignition. The results show that gasoline spray hits the wall of the pre-chamber inevitably leading to soot generation,and the soot generation increases when the amount of fuel injected in the prechamber increases. A richer mixture in the pre-chamber can improve the combustion phase,speed up the combustion and improve the ignition performance,but a stoichiometric ratio mixture in the pre-chamber has better fuel economy. When the φglobal is less than 1.4,the thermal efficiency of the pre-chamber ignition decreases. When φglobal is greater than 1.4,the thermal efficiency of the pre-chamber ignition begins to improve obviously. The prechamber ignition can extend the lean burn limit to φglobal= 2.1 with 2% mass fraction fuel injected into the prechamber,and the GITE reaches the maximum value of 48.5% when φglobal is 1.8.更多还原