污泥厌氧消化反应器CFD数值模拟研究进展

污泥作为典型的不透明非牛顿流体，在厌氧消化反应器内的流场具有复杂性，难以直接进行流场测试分析。结合计算流体力学（CFD）技术，分析污泥厌氧消化反应器内的流场分布情况，探讨污泥在反应器内混合效果和对消化过程的影响，以验证校核反应器优化设计和运行，改善污泥在消化反应器内的流动和混合性能并最终提高反应器性能。在综合文献及前期研究工作的基础上，系统分析并重点关注了CFD数值模拟过程当中多相流模型和湍流模型的选取、污泥流变特性应用、反应器流场评估优化及耦合生化模型等的研究现状及进展，最后总结了目前污泥厌氧消化反应器CFD数值模拟过程存在的问题。并指出在考量污泥流变学特性的基础上，利用传质模型将反应器流场和生化过程相耦合，构建流场-生化耦合模型，获取基质转化规律，为优化污泥厌氧消化反应器设计运行提供理论依据，是CFD应用于厌氧消化反应器数值模拟的发展方向。

A critical review on CFD simulation of anaerobic digestion reactor for sewage sludge

As an opaque and typical non-Newton fluid, sewage sludge performs a complex rheological behavior, and a complex flow field distribution will occur in an anaerobic digester, which is difficult to test directly. In this study, the visualization of flow field was analyzed with combination of computational fluid dynamics (CFD), then the mixing effect of sludge in an anaerobic digester and its influence on digestion process were investigated, which could verify the optimal design and operation of the digester, and ameliorate the flow and mixing characteristics of sewage sludge. Ultimately, the performance of the digester could be improved. Based on previous research works and extensive literatures, the research status and advances on the selection of multiphase flow models and turbulence models, application of rheological characteristics, evaluation and optimization of the flow field as well as coupled biochemical models in CFD numerical simulation were systemically analyzed and focused on. The review concluded that based on the considering the sludge rheological property, the mass transport model was used to couple the flow field of reactor and biochemical process, then the flow field-biochemical reaction coupling model was built, and the substrate transformation was achieved, which could provide a theoretical basis for optimizing the design and operation of sewage sludge anaerobic digester, and is a development trend for numerical simulation of an anaerobic digester with CFD.