Two-Grid Method for Miscible Displacement Problem by Mixed Finite Element Methods and Mixed Finite Element Method of Characteristics. (17th May 2016)

• Record Type: Journal Article
• Authors: Chen, Yanping; Hu, Hanzhang
• Is Part Of: Communications in computational physics. Volume 19:Number 5(2016:May)
• Page Start: 1503
• Page End: 1528
• Publication Date: 2016-05-17
• Subjects: 35M13, -- 65M12; Two-grid method, -- miscible displacement problem, -- mixed finite element, -- characteristic finite element method; Mathematical physics -- Data processing -- Periodicals; Physics -- Data processing -- Periodicals; 530.150285
• DOI: 10.4208/cicp.scpde14.46s
• Languages: English
• ISSNs: 1815-2406

Abstract

Abstract: The miscible displacement of one incompressible fluid by another in a porous medium is governed by a system of two equations. One is elliptic form equation for the pressure and the other is parabolic form equation for the concentration of one of the fluids. Since only the velocity and not the pressure appears explicitly in the concentration equation, we use a mixed finite element method for the approximation of the pressure equation and mixed finite element method with characteristics for the concentration equation. To linearize the mixed-method equations, we use a two-grid algorithm based on the Newton iteration method for this full discrete scheme problems. First, we solve the original nonlinear equations on the coarse grid, then, we solve the linearized problem on the fine grid used Newton iteration once. It is shown that the coarse grid can be much coarser than the fine grid and achieve asymptotically optimal approximation as long as the mesh sizes satisfy h = H 2 in this paper. Finally, numerical experiment indicates that two-grid algorithm is very effective.