摘要
ETCI(Exhaust Top dead center Injection Compression Ignition)燃烧利用负气门重叠产生的高温残余废气对高压喷入的燃油进行加热促进蒸发,实现了HCCI燃烧。基于ETCI的燃烧模式,研究了排气正时以及增压压力等参数对燃烧过程的影响。试验结果表明,排气正时对燃烧特性有较大的影响,利用排气正时控制残余废气率和IVC时刻缸内平均温度可间接实现燃烧相位的控制;在自然排气状态下,进气压力的升高增大了过量空气系数、可小幅度降低IVC时刻缸内残余废气与新鲜空气的混合气的平均温度,在一定范围内实现燃烧相位的控制。通过不同排气正时下合理的增压压力配合可实现燃烧相位的有效控制并降低排放。
ETCI using internal high temperature of the residual gases to promote fuel evaporation and fuelair mixing is one effective method to realize HCCI. In this paper, ETCI is used to study the effect of exhaust valve timing and boost pressure on combustion process. The study shows that, exhaust valve timing has great effect on combustion. Using exhaust valve timing to control the percentage of residual gases and mean intake temperature in cylinder can indirectly control the combustion phase. In addition, at constant exhaust back pressure, increasing the intake pressure will increase the excess air coefficient and reduce the intake charge mean temperature, leading to the controlling of the combustion phase in some region. Reasonable combination of exhaust valve timing and boost pressure can effectively control the combustion phase and minimize emissions.
出处
《内燃机学报》
EI
CAS
CSCD
北大核心
2008年第5期385-391,共7页
Transactions of Csice
基金
国家重点基础研究发展规划资助项目(2007CB210003)
