某柴油机SCR系统CFD仿真分析

排放法规的日趋严格,柴油机尾气后处理器SCR作为处理NOX排放物的一种有效手段,吸引了越来越多的目光的关注。柴油机尾气后处理器SCR内部的气体流动状况及尿素喷射效果与其使用效率以及柴油机的动力性和经济性都有很大的影响。文章通过建立三维SCR流动和喷雾计算模型,计算得出SCR内部压力、流场分布以及尿素喷射雾化分布情况。通过本次仿真,找到内部影响SCR工作效率的关键设计因素,从而更好的优化产品设计,满足性能及一致性的要求。结果表明:柴油机尾气后处理器SCR内部孔道的分布对于性能有一定的影响,需要通过生产进行控制从而满足尾气后处理的效率及产品一致性要求。

SCR system CFD simulation for some Diesel Engine

With the increasingly strict emission regulations, diesel exhaust processor SCR, as an effective mean to deal with NOX emissions, has attracted more and more attention. The gas flow condition and urea injection effect inside the diesel exhaust processor SCR have great influence on its efficiency and the dynamic and economic of diesel engine.By establishing a three-dimensional SCR flow and spray calculation model, the internal pressure, flow field distribution and urea spray atomization distribution are calculated. Through this simulation, we can find the key design factors that affect SCR’s efficiency, so as to better optimize product design and meet the requirements of performance and consistency. The results show that the distribution of the internal hole of the diesel exhaust processor SCR has some effect on performance, and it needs to be controlled by production to meet the efficiency and product consistency requirements of exhaust gas after treatment.