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Contaminant transport with adsorption in dual-well flow

Jozef Kačur, Roger Van Keer (2003)

Applications of Mathematics

Numerical approximation schemes are discussed for the solution of contaminant transport with adsorption in dual-well flow. The method is based on time stepping and operator splitting for the transport with adsorption and diffusion. The nonlinear transport is solved by Godunov’s method. The nonlinear diffusion is solved by a finite volume method and by Newton’s type of linearization. The efficiency of the method is discussed.

Continuous-time finite element analysis of multiphase flow in groundwater hydrology

Zhangxin Chen, Magne Espedal, Richard E. Ewing (1995)

Applications of Mathematics

A nonlinear differential system for describing an air-water system in groundwater hydrology is given. The system is written in a fractional flow formulation, i.e., in terms of a saturation and a global pressure. A continuous-time version of the finite element method is developed and analyzed for the approximation of the saturation and pressure. The saturation equation is treated by a Galerkin finite element method, while the pressure equation is treated by a mixed finite element method. The analysis...

Convection with temperature dependent viscosity in a porous medium: nonlinear stability and the Brinkman effect.

Lorna Richardson, Brian Straughan (1993)

Atti della Accademia Nazionale dei Lincei. Classe di Scienze Fisiche, Matematiche e Naturali. Rendiconti Lincei. Matematica e Applicazioni

We establish a nonlinear energy stability theory for the problem of convection in a porous medium when the viscosity depends on the temperature. This is, in fact, the situation which is true in real life and has many applications to geophysics. The nonlinear analysis presented here would appear to require the presence of a Brinkman term in the momentum equation, rather than just the normal form of Darcy's law.

Convective Instability of Reaction Fronts in Porous Media

K. Allali, A. Ducrot, A. Taik, V. Volpert (2010)

Mathematical Modelling of Natural Phenomena

We study the influence of natural convection on stability of reaction fronts in porous media. The model consists of the heat equation, of the equation for the depth of conversion and of the equations of motion under the Darcy law. Linear stability analysis of the problem is fulfilled, the stability boundary is found. Direct numerical simulations are performed and compared with the linear stability analysis.

Coupled heat transport and Darcian water flow in freezing soils

Krupička, Lukáš, Štefan, Radek, Beneš, Michal (2013)

Programs and Algorithms of Numerical Mathematics

The model of coupled heat transport and Darcian water flow in unsaturated soils and in conditions of freezing and thawing is analyzed. In this contribution, we present results concerning the existence of the numerical solution. Numerical scheme is based on semi-implicit discretization in time. This work illustrates its performance for a problem of freezing processes in vertical soil columns.

Coupling Darcy and Stokes equations for porous media with cracks

Christine Bernardi, Frédéric Hecht, Olivier Pironneau (2005)

ESAIM: Mathematical Modelling and Numerical Analysis - Modélisation Mathématique et Analyse Numérique

In order to handle the flow of a viscous incompressible fluid in a porous medium with cracks, the thickness of which cannot be neglected, we consider a model which couples the Darcy equations in the medium with the Stokes equations in the cracks by a new boundary condition at the interface, namely the continuity of the pressure. We prove that this model admits a unique solution and propose a mixed formulation of it. Relying on this formulation, we describe a finite element discretization and derive...

Coupling Darcy and Stokes equations for porous media with cracks

Christine Bernardi, Frédéric Hecht, Olivier Pironneau (2010)

ESAIM: Mathematical Modelling and Numerical Analysis

In order to handle the flow of a viscous incompressible fluid in a porous medium with cracks, the thickness of which cannot be neglected, we consider a model which couples the Darcy equations in the medium with the Stokes equations in the cracks by a new boundary condition at the interface, namely the continuity of the pressure. We prove that this model admits a unique solution and propose a mixed formulation of it. Relying on this formulation, we describe a finite element discretization and derive...

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