摘要
以车用4缸直喷式柴油机为样机,研究了负荷、转速和供油提前角变化时,氮氧化物NOx排放的变化规律。排放试验采用的是13工况测试循环。研究结果表明,NOx排放浓度随柴油机负荷的增大而显著增加。在最大转矩、转速2200r/min工况下,其浓度随负荷的增加呈现线性增加;在标定转速3200r/min工况下则呈现指数函数的增加。随着供油角度的延迟,NOx排放值显著降低,微粒PM排放值有一定程度的增加,油耗略有升高。二氧化氮NO2排放在NOx总排放中占有一定的比重,在低负荷时可以达到35%以上。这表明在评价柴油机NOx的排放量时,仅考虑一氧化氮NO是不完整的,还需要考虑NO2的排放量。该研究对柴油机NOx排放的理论建模及试验研究均有一定的参考价值。
An investigation of the effects of load, speed and injection timing on nitrogen oxides (NOx) emissions in an automobile diesel engine was conducted. The engine was a 4cylinder, direct injection diesel engine with a displacement of 2156 L. ECE R49 13mode test cycle was performed on the engine. The results show that the concentrations of NOx increase with the increase in the engine load. There is a linear function between the concentrations of NOx and BMEP under 2 200 r/min (speed at maximum torque), and there is an exponential function between the two parameters under 3 200 r/min (rated speed). The concentrations of NOx decrease markedly with the retarded injection timing, but the concentration of particulate matter (PM) rises with a certain extent and the BSFC has a very small increase. The content of nitrogen dioxide (NO2) in NOx is a noticeable parameter, and it can reach over 35% at lower loads. This indicates only nitric oxide (NO) was considered is incomplete when NOx emissions are evaluated, NO2 emission should be taken into account. The study is useful for modeling NOx emissions, as well as experimental investigations of NOx.
出处
《内燃机学报》
EI
CAS
CSCD
北大核心
2003年第6期435-439,共5页
Transactions of Csice
基金
国家重点基础研究发展规划项目(2001CB209205)。
