一种带有多孔隔板设计的SCR混合器研究

Investigation of SCR Mixer with Porous Baffle Design

为满足日益严苛的排放法规要求,对车用柴油机尾气后处理系统提出了更高的尾气处理要求。通过对SCR混合器的孔板位置及大小尺寸进行仿真优化分析,发现左下角开孔面积增大、右上角孔位减少可以有效提高氨分布均匀性。利用计算机辅助模拟的手段对柴油机后处理系统的选择性催化还原氨分布均匀性指数进行了优化,对SCR前端的混合器孔板优化后氨分布均匀性指数≥0.95,较原设计改善了6%,有效提高了SCR的反应效率。

In order to meet the increasingly stringent emission regulations,higher exhaust gas treatment requirements are put forwaed for the exhaust gas aftertreatment system of automotive diesel engines.Through the simulation optimization analysis of the position and size of the orifice,it is found that the increase of the hole area in the lower left corner and the decrease of the hole position in the upper right corner can effectively improve the uniformity of ammonia distribution.The uniformity index of the selective catalytic reduction of ammonia distribution in the diesel engine aftertreatment system was optimized by means of computer-aided simulation.After optimizing the mixer orifice plate of the SCR front end,the uniformity index of ammonia distribution is greater than or equal to 0.95,which is an improvement of 6%compared with the original design,which effectively improves the reaction efficiency of SCR.