发动机处于冷起动、低温运转工况时,由于气缸内的涡流强度较弱、温度较低、形成的混合气品质较差及缺火等原因,使得可燃混合气燃烧不完全,HC和CO的排放量增大。实验表明,冷起动工况下HC的排放量占HC总排放量的60％～80％。因此,对发动机冷起动、低温工况的尾气进行净化是十分必要的。国外一些公司研究开发了蓄热器、未燃烃(HC)吸附器和电加热三效催化转化器等来改善冷起 Engine at cold start, low temperature conditions, due to the weak cylinder vortex, the temperature is low, the formation of the poor quality of the mixture and lack of fire and other reasons, making the combustion of combustible mixture incomplete combustion of HC and CO emissions Increase in volume. Experiments show that under cold start HC emissions accounted for 60% to 80% of the total emissions of HC. Therefore, the engine cold start, low temperature conditions of the exhaust gas purification is very necessary. Some foreign companies research and development of the regenerator, unburned hydrocarbon (HC) adsorber and electric heating three-way catalytic converter to improve the cold