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A Uniaxial Compression Experiment with CO2-Bearing Coal Using a Visualized and Constant-Volume Gas-Solid Coupling Test System
Published on: June 12, 2019
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Liquid Seepage in Coal Granular-Type Porous Medium
Kang Wang1, Wei Tan1, Yukun Zhu1
1School of Chemical Engineering and Technology, Tianjin University, Tianjin 300350, China.
ACS Omega
|August 25, 2020
Summary
Liquid penetration into coal requires sufficient head pressure. Higher pressure and larger pores increase seepage velocity, while liquid viscosity causes energy dissipation in porous media.
Area of Science:
- Geosciences
- Fluid Dynamics
- Materials Science
Background:
- Understanding liquid seepage in coal is crucial for resource extraction and environmental management.
- Coal's granular porous structure presents complex flow dynamics.
Purpose of the Study:
- To investigate liquid seepage in coal granular porous media.
- To analyze the influence of head pressure, liquid viscosity, and pore size on seepage.
- To develop models for simulating liquid flow in coal.
Main Methods:
- Designed a novel sampling device for coal samples with controlled porosity.
- Utilized ultra-deep-field microscopy and digital image processing to create porous medium models.
- Employed Computational Fluid Dynamics (CFD) for simulating liquid seepage processes.
Main Results:
- A critical head pressure is necessary for liquid penetration into coal.
- Hydraulic conductivity and permeability positively correlate with driving head pressure.
- Liquid viscosity increases flow deformation and eddy current energy dissipation.
- Larger pores reduce flow resistance, enhancing kinetic energy and seepage velocity.
Conclusions:
- Seepage dynamics in coal are governed by a complex interplay of pressure, viscosity, and pore structure.
- The study provides insights into factors controlling liquid flow in granular porous media.
- Findings are relevant for optimizing fluid management in coal-related applications.
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