基于仿真与试验的SCR混合器开发及验证  

Development and Validation of a SCR Mixer Based on Simulation and Experiments

作　　者：王天田 黄志超 胡杰[3] 王智 Wang Tiantian;Huang Zhichao;Hu Jie;Wang Zhi(School of Mechanical and Electrical Engineering and Vehicle Engineering,East China Jiaotong University,Nanchang 330013,China;New Energy&New Power Research Institute,Jiangling Automobile Company Limited,Nanchang 330100,China;School of Automotive Engineering,Wuhan University of Technology,Wuhan 430070,China;AVL List Technical Center(Shanghai)Company Limited,Shanghai 200121,China)

机构地区：[1]华东交通大学载运工具与装备教育部重点实验室,江西南昌330013 [2]江铃汽车股份有限公司新能源新动力研究院,江西南昌330100 [3]武汉理工大学汽车工程学院,湖北武汉430070 [4]李斯特技术中心(上海)有限公司,上海200121

出　　处：《内燃机学报》2023年第4期351-360,共10页Transactions of Csice

基　　金：中国博士后科学基金资助项目(2022M711353);江西省自然科学基金资助项目(20202BABL314037);移动污染源排放控制技术国家工程实验室资助项目(NELMS2017A08);南昌市新能源汽车动力电池安全重点实验室资助项目(2021-NCZDSY-004).

摘　　要：为解决国Ⅵ排放法规下柴油机后处理系统尿素结晶风险过高的问题,提出了一种选择性催化还原(SCR)系统混合器设计优化及性能验证方法.首先,借助计算流体动力学(CFD),对建立的后处理系统模型进行了4种典型工况条件下速度场和氨(NH3)分布均匀性等性能的数值仿真,然后通过台架进行NH3分布均匀性试验对仿真过程进行优化,基于对优化后仿真结果的分析,提出了一种结合破碎格栅、导流装置和微孔整流板等设计元素的混合器优化方案.高温高速工况下,该方案可在基本不影响排气背压情况下将SCR1载体内部的速度分布均匀性从0.951提升至0.976,NH3分布均匀性从0.947提升至0.979,瞬态尿素结晶风险试验结果表明:该方案具备优异的混合性能与抗结晶性能.Development and validation method of a selective catalytic reduction(SCR)mixer was proposed for diesel engine after-treatment system deposit risk control to meet ChinaⅥemission regulation.Firstly,a numerical simulation model of the after-treatment system was established using computational fluid dynamics(CFD),and the physicochemical processes was optimized and parameterized by NH3 distribution uniformity test.Then,based on the simulation and test results,the broken grille,diversion device and micro-hole board were designed for better mixing and NH3 distribution uniformity.Simulation results show that under high temperature and high speed conditions,the velocity distribution uniformity in SCR1 is improved from 0.951 to 0.976,and the NH3 distribution uniformity is improved from 0.947 to 0.979 with a negligible increase of pressure loss.High mixing performance and excellent anti-deposition capability can be also shown from the transient urea deposition test results.

关 键 词：柴油机 选择性催化还原 混合器 NH3分布均匀性 

分 类 号：TK421.5[动力工程及工程热物理—动力机械及工程]