进气道对缸内直喷增压汽油机性能的影响  

Intake Port Effect on the Performance of a Turbocharged Gasoline Direct Injection Engine

作　　者：张小矛[1,2] 高卫民[1,2] 辛军[2] 钱承炬[2] 平银生[2] 陈明[2] 倪计民[1] 张万平[2] 

机构地区：[1]同济大学汽车学院,上海201804 [2]上海汽车集团股份有限公司乘用车公司技术中心,上海201804

出　　处：《内燃机学报》2011年第4期300-306,共7页Transactions of Csice

摘　　要：应用稳态CFD方法对高、低滚流比进气道进行了分析,高滚流比气道较低滚流比气道流量系数降低16%,滚流比提高22%.基于这两种气道对缸内直喷增压汽油机进气和压缩冲程油气混合的影响进行了瞬态CFD分析.结果表明,高滚流比气道在缸内能形成更规则的大尺度漩涡,且缸内瞬态滚流比更高,两种对称气道瞬态涡流比基本为零,进气道流量系数对增压发动机进气充量影响较小;高滚流比气道的缸内油气分布比低滚流比气道更均匀,湍动能也高.因此,缸内直喷增压汽油机宜采用高滚流比气道.最后,通过试验验证表明,高滚流比气道燃烧在低速1,500,r/min满负荷时提前5°CA左右,中速3,000,r/min满负荷时提前3°CA左右,高速时两者差别不大;高滚流比气道燃烧持续期较低滚流比气道缩短2°CA左右,缸内平均指示压力循环波动系数较低滚流比气道有明显的降低,燃烧稳定性改善20%～30%,油耗率降低5%～10%,HC和CO排放降低明显,NOx排放有所升高.Steady state CFD analysis of high tumble intake port（HT port）and low tumble intake port（LT port）were conducted.The flow coefficient of HT port decreases by 16%,but tumble ratio increases by 22% in comparison to those of LT port.Effect of the two intake ports on fuel-air mixing in a turbocharged gasoline direct injection engine during intake and compression strokes was analyzed.Results show that HT port can generate better structured large-scale eddy than LT port.The transient tumble ratio of HT port is higher than that of LT port and the swirl ratios of two symmetrical ports are almost equal to zero.The per-formance of turbocharged gasoline engine is not sensitive to the flow coefficient of intake ports.The fuel-air mixture of HT port is more uniform than that of LT port.Turbulent kinetic energy value of HT port is higher than that of LT port.Thus,high tumble port is suitable for turbocharged gasoline direct injection engine.The test results show that the position at which 50% mass fraction burned of HT port advances 5°CA and 3°CA,at 1 500 r/min and 3 000 r/min under full load,respectively,but it has little difference at high speed between the two ports.Combustion duration of HT port is 2°CA shorter than that of LT port.CoV in IMEP of HT port decreases significantly compared with that of LT port.Combustion stability with HT port improves by 20%～30%,brake specific fuel consumption decreases by 5%～10%,HC and CO emissions of HT port decrease significantly,but NOx increases moderately in comparison to LT port.

关 键 词：缸内直喷汽油机 进气道 涡轮增压 滚流比 

分 类 号：TK464[动力工程及工程热物理—动力机械及工程]