A model for hydrodynamic influence on a multi-layer deformable coal seam

摘要

The paper suggests a mathematical model of hydrodynamic influence on a multi-layer deformable coal seam, based on transient poroelastic equations with regard to nonlinear dependence on the pressure for the filtration coefficients. For numerical simulation a general problem setting is given, and the semi-discrete finite element approximations and time integration schemes for the equations of the finite element method are provided. By using an analogy between poroelasticity and thermoelasticity the transient nonlinear poroelastic problem obtained is solved as a corresponding thermoelastic problem. As example, an axisymmetrical problem with input data corresponding to a real-world experiment of a hydrofracture in a three-layer coal seam is considered. The computational results allowed to estimate the radius of the degassing zone and verify the results obtained previously for a pure filtration problem.