Multiphase flow simulation in hybrid porous structure

Abstract

Recent research has primarily focused on creating biporous and hybrid porous structures with multiple pore sizes and length scales to optimize capillary pressure and permeability. Despite numerous experimental investigations on biporous and hybrid media, there is a noticeable absence of numerical simulations that explore the multiphase flow within these media. Therefore, the present study aims to conduct a pore-scale numerical simulation of two-phase flow in a biporous structure. The biporous structure is proposed by arranging clusters of solid particles in a staggered regular pattern, with each cluster consisting of closely packed particles. The dimensions and characteristics of the simulated structure are based on previous experimental literature on biporous and hybrid media. A monoporous structure simulation is also included for comparison with biporous results. ANSYS Fluent is utilized to carry out the numerical simulations of capillary pumping flow. The simulation results indicate that the permeability and average capillary pressure of the biporous media are four times and over one and a half times higher, respectively, compared to those of the monoporous media. The presence of smaller pathways within each cluster of a biporous and hybrid porous media enhances the capillary effect in comparison to conventional monoporous structures. Additionally, the larger pores between the clusters contribute to a higher permeability of the hybrid porous structure. As a result, the combined effect of increased capillary action and higher permeability leads to improved performance of the hybrid porous structure. Overall, the proposed simplified biporous geometry accurately models fluid flow in real, complex biporous and hybrid structures.