基于孔隙尺度网络模型的多孔介质内湍流流动

Investigation on turbulent flow through porous media based on a pore-network model

为进一步研究大孔隙率内的湍流特性对多孔介质内输运和燃烧过程的影响,提出多孔介质的一种二维孔隙网络模型.该模型由一系列圆形孔隙体和长方形喉道互相连接而成.采用标准k-ε模型模拟孔隙网络内的微观流场,利用体积平均方法将微观流场计算结果转换为宏观流场的信息,从而可确定宏观模型中修正项系数的值.计算结果与文献[3]提出的模型吻合较好.

To further understand essential influences of turbulence on transport and combustion processes in porous media with high porosity, a two-dimensional pore network model for random porous media structure was developed, which consisted of a number of cylindrical pores and parallelepiped connecting throats. A standard k -ε model was employed to simulate the turbulence effect in the microscopic pore-level flow field. Computational results obtained from the pore-network model were transformed into information of the macro flow field through a volume average approach over the entire computation domain. Then the results were used to deduce the value for the unknown coefficient in the macroscopic model. Computational results show that the value agrees well with that of reference 3.