摘要
通过台架试验对一台增压天然气发动机分别采用高压废气再循环(EGR)和高低压废气再循环系统时发动机的燃烧与排放特性进行了试验研究,并结合数值模拟方法对发动机的能量平衡进行了定量分析,探究不同EGR引入系统对天然气发动机经济性的影响.发动机台架试验结果表明:与高压EGR相比,发动机采用高低压EGR系统时,火焰发展期和快速燃烧期缩短,燃烧相位提前,缸内最高燃烧压力和最大瞬时放热率增加;HC和CO排放降低,NOx排放增加;燃气消耗率下降4.5%~9.3%.发动机能量平衡分析结果表明:发动机采用高低压EGR系统时摩擦损失增加,泵气损失、传热损失和排气能量损失减少,其中,排气能量损失的减少幅度最大.
A bench comparative experiment of combustion and emission was carried out for a turbocharged natural gas engine with high-pressure exhaust gas recirculation(HP EGR)and high-low pressure(HLP)EGR system respectively.Then the engine energy balance was quantitatively analyzed by the numerical simulation method and the influences of different EGR systems on fuel economy were investigated.The results of bench test show that the flame developing period and rapid combustion duration shorten,the combustion phase advances,and the peak values of in-cylinder pressure and heat release rate increase after using HLP EGR system.In addition,HC and CO emissions reduce,NOx emission increases and the gas consumption rate reduces by 4.5%to 9.3%.According to the results of energy balance,the pumping loss,in-cylinder heat transfer loss and exhaust energy loss reduce and the reduction of exhaust energy was the largest.Besides,the friction loss increases.
作者
朱赞
董伟
罗坤
黄勇成
ZHU Zan;DONG Wei;LUO Kun;HUANG Yongcheng(Guangxi Yuchai Machinery Co.,Ltd.,Yulin 537005,China;School of Energy and Power Engineering,Xi’an Jiaotong University,Xi'an 710049,China)
出处
《车用发动机》
北大核心
2021年第5期8-14,共7页
Vehicle Engine
基金
国家重点研发计划资助项目(2018YFB0105900)。
