Flow in fractured porous media was first investigated by Barenblatt and Zheltov [1960] et al. means of the double‐porosity model. A direct, exact, complete numerical solution flow such is given this paper for arbitrary distributions permeabilities matrix fracture network. The network are automatically meshed; equations discretized finite volume method. This code has been so far applied to incompressible fluids statistically homogeneous which schematized as spatially periodic media. Some...

Single fractures are generated by statistical methods and described a probability density of the profile heights spatial covariance function which is either Gaussian or self-afline.The results numerical simulations bised on both 2D Reynolds 3D Stokes equations presented.Total fluxes predicted these for same given discussed.The difference between predictions models analysed range correlation lengths apertures real fractures, it found that total may differ more than two times.When local...

The permeability of geological formations which contain fractures with a power-law size distribution is addressed numerically by solving the coupled Darcy equations in and surrounding porous medium. Two reduced parameters are introduced allow for unified description over very wide range fracture characteristics, including their shape, density, distribution, possibly size-dependent permeability. general models proposed loose dense networks, they provide good representation numerical data...

The asymptotic behaviors of the permeability isotropic fracture networks at small and large densities are characterized, a general heuristic formula is obtained which complies with limiting accurately predicts these over whole density range. Theses developments based on extensive numerical calculations theoretical arguments inspired by examination flow distribution in fractures densities. Then, results extended to anisotropic Fisher orientations, polydisperse networks, fractured porous...

The influence of various parameters such as the domain size, exponent power law, smallest radius, and fracture shape on percolation threshold networks has been numerically studied. For large domains, adequate parameter is dimensionless density normalized by product third moment radii distribution factor; for regular polygons, critical depends only slightly fractures; a model proposed fractures with elongated shapes. In small analyzed in terms sum two reduced moments distribution; this...

Two-phase flow in fractured porous media is investigated by means of a direct and complete numerical solution the generalized Darcy equations three-dimensional discrete fracture description. The model applies to arbitrary network geometry, distributions permeabilities matrix fractures. It used here order obtain steady-state macroscopic relative random media. Results are presented as functions mean saturation discussed comparison with simple models.

The percolation threshold of fracture networks is investigated by extensive direct numerical simulations. fractures are randomly located and oriented in three-dimensional space. A very wide range regular, irregular, random shapes considered, monodisperse or polydisperse containing with different and/or sizes. results rationalized terms a dimensionless density. simple model involving new shape factor proposed, which accounts efficiently for the influence shape. It applies good accuracy...

Fracture network permeability is investigated numerically by using a three-dimensional model of plane polygons uniformly distributed in space with sizes following power-law distribution. Each triangulated via an advancing front technique, and the flow equations are solved order to obtain detailed pressure velocity fields. The macroscopic determined on scale which significantly exceeds size largest fractures. influence parameters fracture distribution--the exponent minimal radius--on...

A numerical study of three‐dimensional solute transport at fracture intersections by using a particle tracking technique is presented. Two models orthogonal intersection are considered, namely, two parallel‐walled channels and rough‐walled Gaussian fractures. The fluid velocity calculated solving the Stokes equation with no‐slip boundary condition solid wall. Examples individual trajectories particles first given in order to illustrate main features phenomenon. Solute mass partitioning...

In most geological instances, 2-D or 3-D fracture distributions are not available from field data. We show here that when data relative to fractures collected along a line such as road well, estimations can be given the major geometrical properties of corresponding networks, volumetric density fractures, their percolation character and macroscopic permeability. All these formulae analytical split into two parts; first one derived measured data, while second requires some assumption on...

Abstract Among hydrogeological processes, free convection in faults has been cited as a possible cause of gold mineralization along major fault zones. Here, we investigate the effects to determine whether it can giant orogenic deposits and their regular spatial distribution fault/shear The approach comprises: (i) coupled two‐ three‐dimensional numerical heat‐ fluid‐flow simulations simplified geological models; (ii) calculation rock alteration index (RAI) delineate regions where...

Spiky particles are constructed by superposing spheres and oblate ellipsoids. The resulting star (but nonconvex) randomly packed a sequential algorithm. geometry, the conductivity, permeability of packings systematically studied. Overall correlations proposed to approximate these properties when geometry particle is known.

Abstract Barometric pumping plays a crucial role in the release of trace gases from fractured porous media to atmosphere, and it requires rigorous complete modeling order go beyond approximate schemes available literature. Therefore, coupled set convection convection‐diffusion equations for slightly compressible fluid unsteady conditions should be solved. The numerical methodology is presented, applied close ones Roselend Natural Laboratory (France). precision code assessed mechanism...

The geometry of real fractures is modeled by random surfaces numerically generated. fracture space and the contact area are determined spatial distribution upper lower surfaces. mean aperture analytically studied. number calculated for with different height covariance functions. percolating properties structure cluster formed in determined. \textcopyright{} 1996 American Physical Society.

A general three‐dimensional numerical model for single‐phase, slightly compressible flow through fractured porous media is introduced. It based on a discrete fracture representation. Applications to the simulation of pressure drawdown well tests are presented, complex situations where intercepts random network with various densities and conductivities. The response can be modeled as function its interconnectivity network.

The homogenization procedure is applied to the problem of wave propagation in biphasic mode porous media saturated with a Newtonian fluid. local problems corresponding solid and fluid phases have been solved separately for complex three-dimensional media. effective rigidity tensor, some coefficients, dynamic permeability, celerities, attenuation three waves are systematically determined. characteristic length Lambda was successfully used gather results permeability as well coefficients all

The percolation and conductivity of self-affine fractures are investigated over the whole range their mean aperture roughness exponent H, by direct three-dimensional numerical simulations. A scaling behavior is exhibited for tight in scale range, with H. All data can be summarized two simple models, valid small to moderate large apertures, respectively.

This paper examines the various regimes that may prevail in a smouldering process combustible porous medium, and their consequences from physical point of view for formulation macroscopic description. A set governing parameters are first identified, by use dimensional analysis. Then, influence is illustrated direct detailed numerical simulations on microscale. In particular, lack local thermodynamic equilibrium demonstrated many situations, which prevents rash application simple homogenized...

A three-dimensional, microscale numerical model for the simulation of smouldering in fixed beds solid fuels is presented. It solves local governing equations, and therefore explicitly accounts coupling transport reaction mechanisms on microscopic scale. This article describes conceptual apparatus provides illustrative examples calculations. Extensive applications will be presented two companion papers.

Loose packings of spheres with bidisperse or log-normal distributions are generated by random sequential deposition. Porosity, conductivity, and permeability determined. The porosities correspond to loose packings, but they follow the usual trends for packings. conductivity power laws as functions porosity Several other quantities such classical Kozeny constant successfully represented porosity. Some dimensionless representations gather numerical data on curves valid all particle...