喷射参数对柴油机SCR内部NH_3均匀性影响分析  

Influence Analysis of Injection Parameters on NH_3 Uniformity in Diesel Engine SCR

作　　者：张东剑[1] 马其华[1,2] 任洪娟[1] 张璐璐[1] 

机构地区：[1]上海工程技术大学汽车工程学院,上海201620 [2]东华大学高性能纤维及制品教育部重点实验室(B类),上海201620

出　　处：《汽车工程学报》2017年第4期299-305,共7页Chinese Journal of Automotive Engineering

基　　金：高性能纤维及制品教育部重点实验室开放课题基金(E2-6203-16-09-(2016)NO.2)

摘　　要：研究尿素喷射参数对选择性催化还原(Selective Catalytic Reduction,SCR)系统催化箱载体内部NH_3分布均匀性的影响。选择典型发动机工况的排气流量、尾气体成分比例、排气温度、压力等物理信息作为边界条件,应用计算流体动力学(Computational Fluid Dynamics,CFD)方法对SCR系统进行全尺寸模拟,并提出了NH_3均匀性系数γ来评价六串孔催化箱入口截面NH_3的均匀性程度。研究分析了5个尿素喷射位置、4种喷射角度对入口截面NH_3均匀性的影响。结果表明,在90°弯管喷射位置、45°喷射角度,六串孔催化箱入口截面的NH_3均匀性最好。The paper studied the effects of urea injection parameters on the uniformity of NH_3 distribution in the catalyst carrier of selective catalytic reduction（SCR） system. Based on the engine bench test, the physical parameters such as the exhaust gas flow rate, the ratio of gas components, the temperature, pressure etc. under typical engine working conditions were selected as boundary conditions to simulate the overall SCR system by using the computational fluid dynamics（CFD） method. The NH_3 uniformity coefficient was used to evaluate the degree of uniformity on the entrance cross section of the catalytic box and the effects of 5 urea injection positions and 4 injection angles on the inlet NH_3 uniformity were studied. The results show that the best NH_3 uniformity is achieved with the injection at the position of the 90 degree elbow and at a 45 degree angle.

关 键 词：柴油机 选择性催化还原 喷射参数 NH3均匀性 

分 类 号：TK422[动力工程及工程热物理—动力机械及工程]