Study of Rock Dilation Effect on Oil Recovery during Steam-Assisted Gravity Drainage

The work is devoted to the numerical study of shear dilation effect on oil recovery rate on the base of the originally develop coupled thermo-hydro-mechanical model. The governing equations of the model include momentum, mass and energy balance laws which are supplemented by constitutive equations and state laws. Filtration of each phase is described by Darcy's law. Effect of pore fluid on stress-strain state of the reservoir is described within Biot theory. Hook's law is applied to evaluate elastic strains. Plastic strains are estimated by associated flow rule with Drucker-Prager yield criterion. Numerical simulation is carried out in the finite-element software Comsol Multiphysics using Weak Form PDE Interface, Heat Transfer and Solid Mechanics modules. Field-scale simulation of reservoir area containing injection well has shown that the model can successfully describe surface heave induced by shear failure as well as increase in porosity and permeability values. Moreover, the obtained results have shown that the oil recovery rate gives lower values when plastic strains are not taken into account. (C) 2022 The Authors. Published by Elsevier B.V.