An Experimental and Numerical Study of Abrupt Changes in Coal Permeability with Gas Flowing through Fracture-Pore Structure

Coal permeability is related to the fracture-pore structure of coal and a key factor in determining gas drainage efficiency. The characteristics methane flow fractures are different from those matrix pores. However, due difficulty observing fast fractures, effect on has seldom been considered investigated. In this study, cylindrical sample used for measurement under pressures, an abrupt change evolution was observed. Then, tandem model adopted analyze these new phenomena. model, deformation directly analyzed modeled without reversed derivation. With consideration elastic modulus controlled by effective strain adsorption-induced matrix. research results show that (1) quickly significantly influence resisting deformation; (2) complete consists caused slow matrix; (3) low efficiency mass exchange between leads two-stage desorption permeability.