直喷汽油机催化器快速起燃的试验研究

摘要

针对EA888直喷汽油机建立了试验台架及试验测控系统,通过试验研究了过量空气系数和两次喷射比例对催化器起燃特性的影响规律.试验结果表明,采用微稀的混合气有利于催化器的快速起燃,采用两次喷射有助于推迟点火,提高排气温度,缩短催化器起燃时间.%A test bench and its control system are established for EA888 direct injection gasoline engine, and an experimental study is conducted on the rule of the effects of excess air coefficient and the fuel proportion ratio in two-stage fuel injection on the light-off characteristics of catalytic converter. The results show that a slight-lean mixture is conducive to the rapid light off of catalytic converter, and two-stage injection helps delay ignition, raise exhaust temperature and shorten the light-off time of catalyst.