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Compared with conventional reservoirs, shale gas flow is greatly affected by matrix/fracture deformation, as well as nonlinear coupled transport mechanisms. In this paper, a hydro-mechanical coupled model is presented to describe the fluid flow in deformable shale formation. A unified compositional model is developed for modeling of multiphase fluid flow with phase transition. A series of mechanisms, including Knudsen diffusion, multi-component adsorption, confined phase behavior and molecular diffusion, are considered for accurate description of fluid flow in shale reservoirs. Matrix deformation is based on the linear poroelasticity theory. The fractures with complex geometry are modeled with the embedded discrete fracture model (EDFM). The mechanical responses of fractures are handled by different constitutive models, which are implemented into the coupled model. The flow and geomechanical models are spatially discretized using finite volume method (FVM) and finite element method (FEM), and the sequentially iterative approach is applied for solving the coupled model. Then the impacts of fracture orientation, in-situ stress condition, and bottom hole pressure on the mechanical deformation and gas production are investigated through sensitivity analysis. With multiple mechanisms and dynamic fracture behavior incorporated, the geomechanical response and well performance in shale condensate gas reservoirs can be accurately captured.
