为提高选择性催化还原(SCR)脱硝反应器内催化剂的脱硝效率和使用寿命，从细观和宏观两个角度对SCR脱硝反应器的流动特性多尺度数值进行研究。在细观层面研究了不同高度的催化剂层产生的阻力随进口速度的变化，并计算得到阻力关系式。宏观层面，基于阻力关系式，计算出催化剂宏观结构数值模拟所需的粘性阻力系数和惯性阻力系数，对反应器内的流动特性进行数值模拟，并将其结果与实验数据对比，最大误差为8.6%。将关系式应用于具有不同结构(蜂窝状和斜板状)催化剂的脱硝反应器中，计算结果与文献值趋势基本一致，最大误差为12.9%。
With the development of computational fluid dynamics (CFD) technology, a lot of scholars have applied CFD method and its related software to study the flow characteristics in the selective catalytic reduction (SCR) denitration reactor. However, when using CFD software for numerical calculation, the relevant parameters of the catalyst such as porosity, viscous drag coefficient and the like are usually empirically obtained. Whereas there is no doubt that this method will increase the calculation error. Therefore, in order to improve the denitration efficiency and service life of the catalyst in the SCR denitration reactor, multi-scale numerical study on the flow characteristics of SCR denitration reactor was conducted in this work from both mesoscopic and macroscopic perspectives. At the mesoscopic level, the relationship between the resistance with different catalyst layer thickness and the inlet velocity was studied, and the formula of the resistance was calculated. At the macroscopic level, based on the above relationship, the viscous drag coefficient and the inertia drag coefficient which are required for the macrostructure numerical simulation of the catalyst were calculated. The flow characteristics in the reactor were numerically studied, the numerical results were compared with the experimental data, and the maximum error was 8.6%, which indicated that the multi-scale numerical simulation method proposed was reliable. In addition, the above relationship was also used to the denitration reactor with different structures of catalysts (such as honeycomb and oblique plate), and the calculation results were compared with the data in the literature. The results showed that the trends were consistent and the maximum error was 12.9%, which further demonstrated that the formula obtained in this work had popularization and application value. The research results of this work had certain theoretical and practical value for the structural optimization of SCR denitration reactor.
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