摘要
在一台京五柴油机上,燃用国Ⅴ柴油,进行了原机的WHTC冷热态试验。根据排气中的氧浓度计算缸内混合气过量空气系数Ф_(at)。研究发现:WHTC冷热态循环中,Ф_(at)^(-1)峰值的出现伴随着NO_x峰值的生成。NO_x峰值生成时刻与相应的Ф_(at)^(-1)峰值出现的时刻之间存在一定相位差,该相位差可正、可负、可为零,且随着NO_x峰值的增大,该相位差呈现逐渐增大的趋势。试验结果表明:NO_x瞬时浓度与Фat的关系呈近似幂律分布。
Cold and hot-started WHTC tests were conducted on a Beijing V stage diesel engine fueled with State- V diesel. Excess air ratio（Фat,） of the mixture in cylinders can be deduced from oxygen concentration of engine exhaust. During the WHTC cycles, spikes of NO, form in accordance with the spikes of Фat^-1 There are phase differences between the arrival time of NOx spikes and the arrival time of the spikes of Фat^-1. The values of phase differences can be positive,negative or zero. With NOx spikes increased,the phase differences exhibit an increasing trend. It is also found that there are power-law distribution patterns between NOx and Фat.
出处
《小型内燃机与车辆技术》
2017年第2期64-68,共5页
Small Internal Combustion Engine and Vehicle Technique
关键词
瞬态循环
过量空气系数
氮氧化物
峰值
幂律分布
Transient cycle
Excess air ratio
Nitrogen Oxides
Spikes
Power-law distribution
