Modelling anisotropic adsorption-induced coal swelling and stress-dependent anisotropic permeability

To investigate the anisotropy of coal swelling, this study proposes an effective stress model for saturated, adsorptive fractured porous media by considering gas adsorption induced surface change on solid-fluid interface. The can be used to capture anisotropic swelling combining mechanical properties and link with permeability. Direction dependent fracture compressibility is describe evolution stress-dependent permeability behaviour. Particularly, impact considered in model. proposed models were tested against experimental results compared relevant existing available literatures. predicts that direction perpendicular bedding plane, greater than parallel plane. Coal each affected changes any directions. plane more sensitive stresses due higher compressibility. cleat could increase adsorption, especially carbon dioxide. Permeability loss significant presented provide a tool quantifying adsorption-induced behaviours.