Numerical Simulation Analysis of Water Injection Seepage Law in Micro Porous Structure of Coal

Abstract

In this paper, a nano Voxel X-ray 3D microscope is used to scan the long flame coal samples and to reconstruct the 3D pore structure by the use of microscopic computed tomography. With image segmentation technique, a model of micro-pore structure of coal is obtained from the reconstructed coal. With different planes selected as seepage inlets, a numerical simulation of low-pressure water seepage is conducted. Studies show that water pressure gradually decreases along the direction of water seepage and reaches the maximum at the pore-pipes with good connectivity near the inlet. Due to the difference between the structure and development direction of pores in the three dimensions, there is an optimal seepage outlet that is most appropriately corresponding to each seepage inlet. When different planes are selected as seepage inlets, the velocity of each seepage outlet is positively correlated with the seepage mass flow rate at the outlet.

The seepage characteristics of coal under the hydraulic-mechanics coupling conditions considering the variation of porosity

“…Zhou et al used image segmentation technology to obtain a coal micropore structure model from the reconstructed coal. With different planes selected as seepage inlets, a numerical simulation of low-pressure seepage is conducted (Zhou et al 2020). Shi used Fluent computational fluid dynamics software to systematically study the seepage process of coal seam water injection under different process parameters and coal seam characteristic parameters, which can provide guidance for optimizing coal seam water injection process parameters, effectively reduce the dust concentration on the working face and improve work surroundings (Shi et al 2019).…”