颗粒接触模型对有序堆积床流动换热影响的数值研究

Effects of Point Contact Treatment Methods on Flow and Heat Transfer of Structured Packed Beds

本文数值研究了不同的接触模型对颗粒有序堆积多孔介质内的流动换热的影响。在堆积多孔介质的数值计算中,颗粒与颗粒之间的接触区域的网格控制是比较困难的,需要进行一定的简化处理。本文详细研究了现有的三种颗粒接触模型-间隙模型,短圆柱模型以及面接触模型对有序堆积床(简单立方堆积SC,体心立方堆积BCC和面心立方堆积FCC)宏观流动换热特性的影响,实验结果发现短圆柱模型得到的数值计算结果与实验结果相符最好;三种模型在堆积床层流流动换热的数值结果相近;在湍流流动中,接触模型对流动的计算结果影响较大。

The treatment of sphere contact is a crucial issue on the numerical analysis of the flow and heat transfer in packed beds of particles. In this paper, the effects of three different treatment methods including introducing a gap, area contacting and cylindrically bridging on flow and heat transfer performances of structured packed beds of particles are investigated with CFD methods. The simulation results have shown that cylindrically bridging method is proved to be reasonable to simplify the sphere sphere contact points. In laminar flow regime, similar results are obtained with three treatment methods. In turbulent flow regime, the point contact treatment methods have significant effects on flow of packed beds.