The search session has expired. Please query the service again.
The search session has expired. Please query the service again.
The search session has expired. Please query the service again.
The search session has expired. Please query the service again.
The search session has expired. Please query the service again.
The search session has expired. Please query the service again.
This paper is a set of lecture notes for a short introductory course on homogenization.
It covers the basic tools of periodic homogenization (two-scale asymptotic expansions, the
oscillating test function method and two-scale convergence) and briefly describes the main
results of the more general theory of G− or
H−convergence. Several applications of the method are given: derivation
of Darcy’s law for flows in porous media, derivation of the porosity...
Two-scale convergence is a special weak convergence used in homogenization theory. Besides the original definition by Nguetseng and Allaire two alternative definitions are introduced and compared. They enable us to weaken requirements on the admissibility of test functions . Properties and examples are added.
We consider applications, illustration and concrete numerical treatments of some homogenization results on Stokes flow in porous media. In particular, we compute the global permeability tensor corresponding to an unidirectional array of circular fibers for several volume-fractions. A 3-dimensional problem is also considered.
The goal of this paper is to present a different approach to the homogenization of the Dirichlet boundary value problem in porous medium. Unlike the standard energy method or the method of two-scale convergence, this approach is not based on the weak formulation of the problem but on the very weak formulation. To illustrate the method and its advantages we treat the stationary, incompressible Navier-Stokes system with the non-homogeneous Dirichlet boundary condition in periodic porous medium. The...
This work studies the heat equation in a two-phase material with spherical inclusions. Under some appropriate scaling on the size, volume fraction and heat capacity of the inclusions, we derive a coupled system of partial differential equations governing the evolution of the temperature of each phase at a macroscopic level of description. The coupling terms describing the exchange of heat between the phases are obtained by using homogenization techniques originating from [D. Cioranescu, F. Murat,...
This paper is devoted to the study of the homogenization of a porous medium, composed of different materials arranged in a periodic structure. This provides the profile of the saturation function for the limit material.
We investigate the diffusion limit for general conservative Boltzmann equations with oscillating coefficients. Oscillations have a frequency of the same order as the inverse of the mean free path, and the coefficients may depend on both slow and fast variables. Passing to the limit, we are led to an effective drift-diffusion equation. We also describe the diffusive behaviour when the equilibrium function has a non-vanishing flux.
We investigate the diffusion limit for general conservative Boltzmann equations with oscillating coefficients.
Oscillations have a frequency of the same order as the inverse of the mean free path, and the coefficients may depend on both slow
and fast variables. Passing to the limit, we are led to an effective drift-diffusion equation.
We also describe the diffusive behaviour when the equilibrium function has a non-vanishing flux.
The aim of this paper is to study a class of domains whose geometry strongly depends on time namely. More precisely, we consider parabolic equations in perforated domains with rapidly pulsing (in time) periodic perforations, with a homogeneous Neumann condition on the boundary of the holes. We study the asymptotic behavior of the solutions as the period of the holes goes to zero. Since standard conservation laws do not hold in this model, a first difficulty is to get a priori estimates of the...
The aim of this paper is to study a class of domains whose
geometry strongly depends on time namely. More precisely, we consider parabolic equations in perforated domains
with rapidly pulsing (in time) periodic
perforations, with a homogeneous Neumann condition on the boundary of the holes.
We study the asymptotic behavior of the solutions as the period ε of the holes goes to zero.
Since standard conservation laws do not
hold in this model, a first difficulty is to get
a priori estimates...
We study the homogenization of the compressible Navier–Stokes system in a periodic porous medium (of period ) with Dirichlet boundary conditions. At the limit, we recover different systems depending on the scaling we take. In particular, we rigorously derive the so-called “porous medium equation”.
Currently displaying 1 –
20 of
28