Numerical Simulation on Mesoscale Mechanism of Seepage in Coal Fractures by Fluid-Sloid Coupling Method

Trying to reveal the mechanism of gas seepage in coal is significance both safe mining and methane exploitation. A series FEM numerical models were built up studied so as explore mesoscale fractures. The proposed model a cube with micron fractures along three orthogonal directions. distribution velocity pressure under fluid-solid coupling was obtained, furthermore, flow flux an equivalent permeability whole calculated. influences fracture width, outlet velocity, situ stress level on investigated. results show that nonlinear Darcy occurs during low zone. increased linearly increasing facture width velocity. certain change lateral coefficient also affects seepage. sharply once deviating isotropic spherical state, but it no longer changed obviously after has been or decreased more than 20%. preliminarily revealed by considering effect, key factors influencing fluid demonstrated. methods will be helpful further study behaviour complex structures.