摘要
为拓展柴油替代燃料的种类,实现短链脂肪酸甲酯在压燃式发动机中的高效低排放,基于一台改装的单缸柴油机,考察了己酸甲酯/柴油、癸酸甲酯/柴油在低温燃烧模式下的燃烧与排放特性。试验过程中保持每循环耗油量为45 mg/cycle,主喷时刻上止点前7度曲轴转角,预喷时刻设置为上止点前60、50、40、30度曲轴转角,预喷燃料的热值分别占总燃料热值的20%和40%。为实现低温燃烧、抑制氮氧化物排放,设定废气再循环比例为40%。研究表明:随着预喷比的提高,低温放热提前;提高预喷比导致CO和HC排放较高,NOx排放较低,指示热效率下降;预喷比对颗粒物排放影响较大;低预喷比下核膜态颗粒物排放较高,高预喷比下积聚态颗粒物排放较高。
To explore the types of alternative fuels for diesel, achieving the high efficiency and low emission of short-chain fatty acid methyl esters in compression ignition engines, the combustion and emission characteristics of methyl hexanoate/diesel and methyl decanoate/diesel in low-temperature combustion mode are examined based on a modified single-cylinder diesel engine. During the test, the fuel consumption per cycle is maintained at 45 mg/cycle, the main injection time is-7 ℃A ATDC, the pre-injection time is set to-60,-50,-40,-30 ℃A ATDC, and the fuel is pre-injected. The heating value of the fuel accounts for 20 % and 40 % of the total fuel heating value. In order to achieve low-temperature combustion and suppress nitrogen oxide emissions, the exhaust gas recirculation ratio is set to 40 %. The experimental results show that with the increase of the pre-injection ratio,the low-temperature heat release is advanced;the increase of the pre-injection ratio leads to higher CO and HC emissions and lower NOx emissions with a decrease in thermal efficiency;the pre-injection ratio has a greater impact on particulate emissions. At low pre-injection ratio, the emissions of nuclear membrane particles is higher;at high pre-injection ratio, the emission of accumulated particles is higher.
作者
吴长贵
周俊冬
钱勇
单新星
WU Chang-gui;ZHOU Jun-dong;QIAN Yong;SHAN Xin-xing(The City Vocational College of Jiangsu(Nantong),Nantong 226006,China;Internal Combustion Engine Institute,School of Mechanical&Power Engineering,Shanghai Jiao Tong University,Shanghai 200240,China)
出处
《南通职业大学学报》
2020年第2期84-89,共6页
Journal of Nantong Vocational University
基金
国家自然科学基金资助项目(51906145)。
关键词
柴油
己酸甲酯
癸酸甲酯
低温燃烧
排放特性
diesel
methyl hexanoate
methyl decanoate
low temperature combustion
emission characteristics
