Janja Kramer, Renata Jecl, Leopold Skerget

The International Conference on Computational & Experimental Engineering and Sciences, Vol.12, No.4, pp. 147-148, 2009, DOI:10.3970/icces.2009.012.147

Abstract A numerical study of double diffusive natural convection in porous media due to opposing buoyancy forces is reported, using the Boundary Domain Integral Method (BDIM). There have been several reported studies dealing with natural convection in porous media, mainly because of its importance in several industrial and technological applications. Less attention, however, has been dedicated to the so-called double diffusive problems, where density gradients occur due to the effects of combined temperature and concentration buoyancy. The current investigation is focused on the special problem, where the thermal and solutal buoyancy forces are opposing each other.
The mathematical model of fluid… More >

B. Gatmiri¹

The International Conference on Computational & Experimental Engineering and Sciences, Vol.4, No.3, pp. 159-166, 2007, DOI:10.3970/icces.2007.004.159

Abstract This document summarizes the basic concepts and steps of establishment of the set of equations of wave propoagation in far field and of the dynamic behaviour of porous media in the near field. A breif description of HYBRID software as a powerful tool for evaluation of local seismic site effect is presented. The Combination of the FEM and BEM and improvement of numerical algorithm for the time truncation are described. More >

Philippe Devloo¹, Wenchao Teng², Chen-Song Zhang^3,∗

CMES-Computer Modeling in Engineering & Sciences, Vol.119, No.1, pp. 145-163, 2019, DOI:10.32604/cmes.2019.04812

Abstract The multiscale hybrid-mixed (MHM) method is applied to the numerical approximation of two-dimensional matrix fluid flow in porous media with fractures. The two-dimensional fluid flow in the reservoir and the one-dimensional flow in the discrete fractures are approximated using mixed finite elements. The coupling of the two-dimensional matrix flow with the one-dimensional fracture flow is enforced using the pressure of the one-dimensional flow as a Lagrange multiplier to express the conservation of fluid transfer between the fracture flow and the divergence of the one-dimensional fracture flux. A zero-dimensional pressure (point element) is used to express conservation of mass where fractures… More >

G. Sciumè^∗,†, S.E. Shelton^‡, W.G. Gray^‡, C.T. Miller^‡, F. Hussain^§,¶, M. Ferrari^¶, P. Decuzzi^¶, B.A. Schrefler^∗,¶

Molecular & Cellular Biomechanics, Vol.9, No.3, pp. 193-212, 2012, DOI:10.3970/mcb.2012.009.193

Abstract Multiphase porous media mechanics is used for modeling tumor growth, using governing equations obtained via the Thermodynamically Constrained Averaging Theory (TCAT). This approach incorporates the interaction of more phases than legacy tumor growth models. The tumor is treated as a multiphase system composed of an extracellular matrix, tumor cells which may become necrotic depending on nutrient level and pressure, healthy cells and an interstitial fluid which transports nutrients. The governing equations are numerically solved within a Finite Element framework for predicting the growth rate of the tumor mass, and of its individual components, as a function of the initial tumor-to-healthy… More >

D. Soares Jr.¹, V. Sladek², J. Sladek², M. Zmindak³, S. Medvecky³

CMC-Computers, Materials & Continua, Vol.27, No.2, pp. 101-127, 2012, DOI:10.32604/cmc.2012.027.101

Abstract This work proposes a modified procedure, based on analytical integrations, to analyse poroelastic models discretized by time-domain Meshless Local Petrov-Galerkin formulations. In this context, Taylor series expansions of the incognita fields are considered, and the related integrals of the meshless formulations are solved analytically, rendering a so called modified methodology. The work is based on the u-p formulation and the incognita fields of the coupled analysis in focus are the solid skeleton displacements and the interstitial fluid pore pressures. Independent spatial discretization is considered for each phase of the model, rendering a more flexible and efficient methodology. The Moving Least… More >

Lianhua Ma¹, Qingsheng Yang^{2, *}

CMES-Computer Modeling in Engineering & Sciences, Vol.114, No.2, pp. 239-259, 2018, DOI:10.3970/cmes.2018.114.239

Abstract Fluid-filled closed-cell porous media could exhibit distinctive features which are influenced by initial fluid pressures inside the cavities. Based on the equivalent far-field method, micromechanics-based solutions for the local elastic fields of porous media saturated with pressurized fluid are formulated in this paper. In the present micromechanics model, three configurations are introduced to characterize the different state the closed-cell porous media. The fluid-filled cavity is assumed to be a compressible elastic solid with a zero shear modulus, and the pressures in closed pores are represented by eigenstrains introduced in fluid domains. With the assumption of spheroidal fluid-filled pores, the local… More >

Taha Sochi¹

CMES-Computer Modeling in Engineering & Sciences, Vol.99, No.2, pp. 151-168, 2014, DOI:10.3970/cmes.2014.099.151

Abstract In this paper, a pore-scale network modeling method, based on the flow continuity residual in conjunction with a Newton-Raphson non-linear iterative solving technique, is proposed and used to obtain the pressure and flow fields in a network of interconnected distensible ducts representing, for instance, blood vasculature or deformable porous media. A previously derived analytical expression correlating boundary pressures to volumetric flow rate in compliant tubes for a pressure-area constitutive elastic relation has been used to represent the underlying flow model. Comparison to a preceding equivalent method, the one-dimensional Navier-Stokes finite element, was made and the results were analyzed. The advantages… More >

Louis C. Foucard¹, John Pellegrino¹, Franck J. Vernerey^1,2

CMES-Computer Modeling in Engineering & Sciences, Vol.98, No.1, pp. 101-127, 2014, DOI:10.3970/cmes.2014.098.101

Abstract Many colloidal-sized particles encountered in biological and membranebased separation applications can be characterized as soft vesicles such as cells, yeast, viruses and surfactant micelles. The deformation of these vesicles is expected to critically affect permeation by accommodating pore shapes and sizes or enhancing the adhesion with a pore surface. Numerical and theoretical modelings will be critical to fully understand these processes and thus design novel filtration membranes that target, not only size, but deformability as a selection criterion. The present paper therefore introduces a multiscale strategy that enables the determination of the permeability of a fibrous network with respect to… More >

R.A. Regueiro^1,2, B. Zhang², S.L. Wozniak³

CMES-Computer Modeling in Engineering & Sciences, Vol.98, No.1, pp. 1-39, 2014, DOI:10.3970/cmes.2014.098.001

Abstract The paper presents three-dimensional, large deformation, coupled finite element analysis (FEA) of dynamic loading on soft biological tissues treated as biphasic (solid-fluid) porous media. An overview is presented of the biphasic solidfluid mixture theory at finite strain, including inertia terms. The solid skeleton is modeled as an isotropic, compressible, hyperelastic material. FEA simulations include: (1) compressive uniaxial strain loading on a column of lung parenchyma with either pore air or water fluid, (2) out-of-plane pressure loading on a thin slab of lung parenchyma with either pore air or water fluid, and (3) pressure loading on a 1/8th symmetry vertebral disc… More >

Ridha Djebali^1,2, Mohamed ElGanaoui³, Taoufik Naffouti¹

CMES-Computer Modeling in Engineering & Sciences, Vol.84, No.6, pp. 499-527, 2012, DOI:10.3970/cmes.2012.084.499

Abstract A thermal lattice Boltzmann model for incompressible flow is developed and extended to investigate the natural convection flow in porous media under the effect of uniform magnetic field. The study shows that the flow behaviour is various parameters dependent. The Rayleigh number (Ra), Hartmann number (Ha), Darcy number (Da) and the medium inclination angle from the horizontal (Φ), the magnetic field orientation (ψ) and the medium porosity (ε) effects are carried out in wide ranges encountered in industrial and engineering applications. It was found that the flow and temperature patterns change significantly when varying these parameters. To confirm the accuracy… More >