柴油机Urea—SCR催化器的数值模拟与优化

运用计算流体动力学（CFD）的方法对某一柴油机Urea—SCR催化器进行了数值模拟，考虑了尿素溶液的喷射雾化、水分蒸发以及热解过程，忽略了载体内部的表面化学反应过程。通过考察载体入口处氨气分布均匀性系数，对有无混合器、不同喷射距离、不同喷孔分布形式及不同喷孔直径条件下的催化器性能进行评估对比，为催化器的进一步优化提供指导性意见。

Numerical Simulation and Optimization of the Urea - SCR Catalyst for Diesel Engine

The numerical simulation of certain diesel engine Urea- SCR catalyst is carried out using computational fluid dynamics method. The injection and atomization of Urea solution, the evaporation of water and the thermolysis of Urea are considered, while the surface chemical reaction in the carrier is ignored. Through the study of ammonia concentration mal - distribution index on the inlet cross - section of the carrier, the performance of the catalyst under different circumstances with or without mixer, under different injection distance, and with different injectors and different orifice diameters is evaluated and compared. This analysis provides some guiding suggestion for further optimization.