The NH₃ uniformity and conversion rate produced by the urea–water solution spray system is an essential factor affecting de-NO_x efficiency. In this work, a three-dimensional simulation model was developed with the CFD software and was employed to investigate the effects of two typical injection methods (wall injection and center injection) and three distribution strategies (pre-mixer, post-mixer, pre-mixer, and post-mixer) of two typical mixers on the urea conversion rate and uniformity. The field synergy principle was employed to analyze the heat transfer of different mixer flow fields. The results show that the single mixer has instability in optimizing different injection positions due to different injection methods and injection positions. The dual-mixer is stable in the optimization of the flow field under different conditions. The conclusion of the field synergy theory of the single mixer accords with the simulation result. The Fc of the dual-mixer cases is low, but the NH₃ conversion and uniformity index rate are also improved due to the increase in the residence time of UWS.

中文翻译：

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基于场协同原理的SCR混合器提高喷雾性能和传热性能的数值分析

尿素水溶液喷雾系统产生的NH ₃均匀性和转化率是影响脱氮_x的重要因素效率。在这项工作中，使用CFD软件开发了一个三维模拟模型，该模型用于研究两种典型注入方法（壁注入和中心注入）和三种分布策略（预混合器，后混合器，预混合器）的影响。混合器和后混合器）两个典型的混合器对尿素的转化率和均匀性。场协同原理被用来分析不同混合器流场的热传递。结果表明，由于不同的注射方法和注射位置，单一混合器在优化不同的注射位置方面存在不稳定。在不同条件下，双混合器在优化流场方面是稳定的。单混频器场协同理论的结论与仿真结果吻合。双重混音器案例的Fc低，由于UWS停留时间的增加，₃转化率和均匀度指数率也得到了改善。