Homogenization of the Poisson equation with Dirichlet conditions in random perforated domains

Ministerio de Ciencia e InnovaciónJunta de Andalucí

Homogenization for advection-diffusion in a perforated domain

The volume of a Wiener sausage constructed from a diffusion process with periodic, mean-zero, divergence-free velocity field, in dimension 3 or more, is shown to have a non-random and positive asymptotic rate of growth. This is used to establish the existence of a homogenized limit for such a diffusion when subject to Dirichlet conditions on the boundaries of a sparse and independent array of obstacles. There is a constant effective long-time loss rate at the obstacles. The dependence of this rate on the form and intensity of the obstacles and on the velocity field is investigated. A Monte Carlo algorithm for the computation of the volume growth rate of the sausage is introduced and some numerical results are presented for the Taylor–Green velocity field

Homogenization problems in random media

we study homogenization problems of partial differential equations in random domains. We give an overview of the classical techniques that are used to obtain homogenized equations over simple microstructures (for instance, periodic or almost periodic structures) and we show how we can obtain averaging equations over some particular random configurations. As it will be seen, such methods require ergodic theory, percolation, stochastic processes, in addition to the compactness of solutions and the convergence process