进气涡流对车用直喷式柴油机微粒排放的影响

Effect of Intake Swirl on Particulate Emission from an Automotive D.I.Diesel Engine

用自行设计的喷气式可变涡流进气系统 (AIVSIS)调节气缸内的涡流水平 ,试验研究了进气涡流对车用直喷式柴油机微粒排放的影响。结果表明 ,中速工况为较低的微粒比排放工况 ,螺旋进气道形成的涡流水平基本可以满足燃料燃烧的要求 ,改变涡流水平对改善柴油机微粒排放贡献不大。而低速高负荷工况是柴油机较高的微粒比排放区 ,适度提高气缸内的涡流水平 ,可以有效降低柴油机微粒的排放量 ,使微粒降低的主要因素是不可溶组分排放的降低。高速工况螺旋进气道形成的涡流水平较高 ,降低气缸内的涡流水平可以降低柴油机微粒的排放量 。

WT5”BZ]The effects of intake swirl on the particulate emission of an automotive D.I.diesel engine were experimentally studied with an air injection variable swirl intake system (AIVSIS).The test results show that in the case of a low speed,and middle and heavy load operating condition,the PT emission could be improved by using an AIVSIS to increase the swirl strength in the cylinder,and the main factor leading to the particulate (PT) emission decrease is the decrease of dry soot (DS) emission.In the case of a middle speed operating condition,the PT emission decreases a little by using an AIVSIS to decrease the swirl strength.The PT emission can be improved significantly by using an AIVSIS to decrease the swirl strength in the cylinder for rated speed operating condition,and the main factor leading to the PT emission decrease is the decrease of SOF emission. [WT5”HZ]