The deformation of fluid elements governs many processes in porous media, including the transport, dispersion and mixing solutes, chemical reactions colloidal particles. Recently, it has been shown that even strongly heterogeneous steady three-dimensional (3-D) Darcy flow with isotropic hydraulic conductivity admits only constrained kinematics. This is due to its inherently helicity-free nature...

Roberto Arnaldo Trancoso Gomes, Renato Fontes Guimarães, Osmar Abílio de Carvalho Júnior , Aline Brignol Menke, Éder de Souza Martins, Sandro Nunes de Oliveira, Nelson Ferreira Fernandes 1 Universidade de Brasília (UnB) – Departamento de Geografia Campus Universitário Darcy Ribeiro, Asa Norte, Brasília, DF. CEP.: 70910-900 Brasil Fone: (61) 3307-2474. Fax: (61) 3272-1909 E-mail: {robertogomes, ...

The use of a constraint (indefinite) preconditioner for the iterative solution of the linear system arising from the finite element discretization of coupled Stokes–Darcy flow is studied. Spectral and field-of-values bounds for the preconditioned system which are independent of the underlying mesh size are presented. Numerical experiments on several twoand three-dimensional problems illustrate ...

SíNDROME DAS PERNAS INquIETAS ASSOCIADA A INSufICIêNCIA CARDíACA E AGRAVADA APóS TROCA VALVuLAR: MALDIçãO DE VéSPER? MD, MSc, PhD, Neurologist, Sleep Disorders Center, Hospital Universitário de Brasília, University of Brasília, Brasília DF, Brazil; MD, PulmonologistSleep Disorders Center, Hospital Universitário de Brasília, University of Brasília, Brasília DF, Brazil; 3 Medicine Student, Univer...

We develop the theory of degenerate and nonlinear evolution systems in mixed formulation. It will be shown that many of the well-known results for the stationary problem extend to the nonlinear case and that the dynamics of a degenerate Cauchy problem is governed by a nonlinear semigroup. The results are illustrated by a Darcy–Stokes coupled system with multiple nonlinearities.

Correction: Noncanonical WNT-5A signaling impairs endogenous lung repair in COPD Hoeke A. Baarsma, Wioletta Skronska-Wasek, Kathrin Mutze, Florian Ciolek, Darcy E. Wagner, Gerrit John-Schuster, Katharina Heinzelmann, Andreas Günther, Ken R. Bracke, Maylis Dagouassat, Jorge Boczkowski, Guy G. Brusselle, Ron Smits, Oliver Eickelberg, Ali Ö. Yildirim, and Melanie Königshoff Vol. 214, No. 1, Januar...

Hellman, F. 2017. Numerical Methods for Darcy Flow Problems with Rough and Uncertain Data. Digital Comprehensive Summaries of Uppsala Dissertations from the Faculty of Science and Technology 1495. 41 pp. Uppsala: Acta Universitatis Upsaliensis. ISBN 978-91-554-9872-6. We address two computational challenges for numerical simulations of Darcy flow problems: rough and uncertain data. The rapidly ...

Effective numerical simulation of many EOR problems requires very accurate approximation of the Darcy velocities of the respective fluids. In this paper we describe a new method for the accurate determination of the Darcy velocity of the total fluid in the miscible displacement of one incompressible fluid by another in a porous medium. The new mixed finite-element procedure solves for both the ...

In this work we propose a method to prescribe essential boundary conditions in the finite element approximation of elliptic problems when the boundary of the computational domain does not match with the element boundaries. The problems considered are the Poisson problem, the Stokes problem and the Darcy problem, the latter both in the primal and in the dual formulation. The formulation proposed...