摘要
通过在六缸重型柴油机上进行汽油/柴油活性控制压燃(reactivity controlled compression ignition,RCCI)燃烧模式的试验,探究了不同喷油定时(start of injection,SOI)、进气压力(inlet pressure,IP)和预混比(premixing ratio,PR)对低负荷RCCI柴油机燃烧与排放特性的影响.结果表明:在燃烧特性方面,随着SOI的提前,第一阶段放热率峰值逐渐增大,对应相位同步提前,滞燃期和缸内平均温度峰值增大;IP的增加会导致滞燃期和缸内平均温度峰值减小;而PR增大使压力升高率峰值和最大累积放热量均降低.在气体排放方面,碳氢化合物(hydrocarbon,HC)与CO排放整体上随着SOI的提前而降低,NO_(x)排放随SOI的提前而增加;HC与CO的排放会随着IP和PR的增加而增加,但PR的增大会使NO_(x)排放减小,且随着SOI的提前,减小幅度先减小再增大.在颗粒物排放方面,核态颗粒物数量浓度随SOI的变化规律不明显,PR较大时IP几乎对核态颗粒物数量浓度没有影响;聚集态颗粒物数量浓度随SOI的变化稍显复杂,在较大PR下,增大IP会使聚集态颗粒物数量浓度减少,且减少幅度随SOI的延迟而变大;与聚集态颗粒物数量浓度相比,在较大PR下IP对减少颗粒物总质量浓度的影响程度更强,但在较小PR下无影响.
The combined effects of different start of injection(SOI),inlet pressure(IP)and premixing ratio(PR)on the combustion and emission characteristics of gasoline/diesel reactivity controlled compression ignition(RCCI)combustion mode under low loads were investigated through experiments on a six cylinder heavy duty diesel engine.The results showed that in terms of combustion characteristics,with the advance of SOI,the peak value of heat release rate in the first stage increased gradually,the corresponding phase advanced synchronously,and the ignition delay and the peak value of in-cylinder average temperature increased.Regarding IP and PR,the increase of IP reduced the ignition delay and the peak value of in-cylinder average temperature,and the increase of PR decreased the peak pressure rise rate and the maximum cumulated heat release.In terms of gas emission,hydrocarbon(HC)and CO emission decreased with the advance of SOI,while NO_(x) increased with the advance of SOI.Increasing IP or PR led to an increase in HC and CO emission,but the increase of PR reduced NO_(x) emission,and with the advance of SOI,the reduction degree first weakened and then increased.In terms of particulate emission,the change of the number concentration of nuclear particles with the advance of SOI was not obvious.Under larger PR condition,IP had almost no effect on the number concentration of nuclear particles.The change of the number concentration of aggregated particles with the variation of SOI was slightly complicated.Under larger PR condition,increasing IP reduced the number concentration of aggregated particles,and the reduction degree increased with the delay of SOI.Compared with the number concentration of aggregated particles,under a larger PR,the increase of IP had a stronger effect on reducing the total mass concentration of particles,but it had no effect under a smaller PR.
作者
韩伟强
唐国强
汪欣
罗强
陆远国
HAN Weiqiang;TANG Guoqiang;WANG Xin;LUO Qiang;LU Yuanguo(Key Laboratory of Automotive Measurement,Control and Safety,Xihua University,Chengdu 610039,China;Department of Ecology and Environment of Nanchong,Nanchong 637000,China;Sichuan Qinie Technology Co.,Ltd.,Guangyuan 628000,China)
出处
《厦门大学学报（自然科学版）》
CAS
CSCD
北大核心
2022年第5期846-855,共10页
Journal of Xiamen University：Natural Science
基金
国家自然科学基金青年科学基金(52006182)
四川省自然科学基金(2022NSFSC0196)
广元市科技计划重点研发项目(21ZDYF0025)
西华大学2019年“青年学者”支持计划项目。
关键词
预混比
喷油定时
进气压力
活性控制压燃
燃烧
排放
premixing ratio
start of injection(SOI)
inlet pressure
reactivity controlled compression ignition
combustion
emission
