报告人: Raheel Ahmed
工作单位: Dimue Technology Co., Ltd, Wuhan
A numerical framework has been developed for the simulation of compositional compressible gas-water phase flow in fractured porous media based on a fully-implicit cell-centred finite-volume method on unstructured grids. We employ discrete-fracture model where fractures are modelled lower-dimensionally, within a rock matrix. A mass balance equation is solved over rock-matrix while lower-dimensional flow equation is solved over lower-dimensional fractures, with coupling terms to account for the flux transfer from the surrounding rock-matrix. The discretisation of the Darcy-fluxes is based on control-volume distributed multi-point flux approximation (CVD-MPFA) coupled with lower-dimensional fractures. The method is suitable to handle fractures within the rock-matrix using unstructured grids. The grid of the matrix conforms to the lower-dimensional fracture cells that act as internal boundaries for the surrounding rock-matrix. We solve a non-linear system for the primary variables that are pressure and component molar densities while secondary variables are updated depending on the updated values of primary variables at each iteration of the non-linear solver.
We use the cubic type equation-of-state (EOS) to model the physical properties of the gas components e.g. CO2. The water phase is multi-component as we allow solubility of gas component in water phase. Solubility of H2O in gaseous phase is also included in the developed scheme. We compare simulation results obtained via the lower-dimensional fracture model and the results obtained by the equi-dimensional fracture model where fractures are modelled by the grid-cells of the same dimension as the surrounding rock-matrix grid. Results are also presented for the CO2 gas flow under gravity through water saturated reservoir with and without fractures. We also present a 3D simulation of multi-component gas injection with CO2 and CH4 into saline water saturated reservoir with a surface fracture network.
Cofounder and Reservoir Simulation Scientist
Dimue Technology Co., Ltd, Wuhan China
PhD Reservoir Simulation, Swansea University UK
Erasmus Mundus MSc (Computational Mechanics), Swansea University UK and Technical University of Catalonia, Spain.
Bachelors of Mechanical Engineering, NUST Pakistan