Influence of ethanol and CN improver on ignition delay of Compression Ignition diesel engine
Ethanol is a kind of renewable energy. It is widely and successfully used in gasoline, however, when it is mixed with diesel to be used in CI engine, the cetane number (CN) of fuel blend must be considered. CN improver, such as iso-amyl nitrite, is generally added to compensate the decrease of CN due to ethanol addition. A combined complicated mechanism was developed to study the auto-ignition of n-heptane/ethanol/iso-amyl nitrite mixture, where n-haptane is to substitute diesel. The developed mechanism was validated against the shock-tube data and HCCI engine combustion data. The effects of ethanol and iso-amyl nitrite addition on the ignition delay of diesel were studied respectively. The result shows that the addition of ethanol will consumes OH radicals which decreases the amount of OH radicals, and consequently retards the ignition time. Numerical analysis indicates that the ignition-enhancing effect of iso-amyl nitrite is due to its thermal decomposition, through which the reactive heptyl and NO radical are generated. Both of them accelerate the low temperature reactions and shorten the ignition delay.
Liu shenghua Liu jie Li yi Li guangle Chi lei Zhu zan
Xian Jiaotong University
国际会议
天津
英文
1-7
2009-08-19（万方平台首次上网日期，不代表论文的发表时间）