Research On Numerical Simulation Of Single-Phase Multi-Component Compressible Fluids Flow In Porous Media

Single-phase multicomponent widely exists in reservoirs,groundwater contamination,and so on,and thus it is of great scientific importance to research them by numerical simulation.In this paper,the mathematical models of compositional flow single-phase in porous media is constructed to preserve the physical properties and effective numerical algorithms and experimental research by numerical simulation.The mathematical models of compressible multicomponent single-phase Darcy flow in porous media consist of the Darcy equation,which describes the flow velocity and pressure,and a set of partial differential equations consisting of the mass conservation equations for each component and the corresponding initial and boundary conditions.These equations are coupled with each other and have highly complex nonlinear properties that require the designs of efficient and stable numerical schemes to solve them.Numerical simulation for petroleum reservoir,the widely used numerical solution method for the time discretization uses the IMPEC(Implicit Pressure and Explicit Concentration)scheme,i.e,the pressure equation is first derived and the time discretization of the pressure equation is treated implicitly,and then the time discretization of the component equations is updated explicitly.In view of the above problems for the mass conservation existed in the classical IMPEC scheme,a preserving-physics IMPEC method is proposed for all components,which is rigorously demonstrated in this paper to have the property of mass conservation for all components.The Cell-Centered Finite Difference(CCFD)discretization method with local mass conservation is widely used for the spatial discretization of porous media flow problem models.In this paper,we adopt a combination of upwind(Upwinding)scheme and CCFD(Up CCFD)for spatial discretization.In this paper,the nonlinear pressure equations generated by combining IMPEC and Up CCFD discretization are solved by an iterative method,and the convergence of the iterative scheme is rigorously proved.Finally,programs the constructed algorithm and conducts some numerical experiments to verify the properties of the constructed numerical algorithm and gives some more complex examples to numerical simulation for the single-phase multi-component flow problems to verify the effectiveness of the proposed algorithm in this paper.