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,...
We tried to reproduce results measured in the wind tunnel experiment with a CFD simulation provided by numerical model PALM. A realistic buildings layout from the Prague-Dejvice quarter has been chosen as a testing domain because solid validation campaign for PALM simulation of Atmospheric Boundary Layer (ABL) over this quarter was documented in the past. The question of input data needed for such simulation and capability of the model to capture correctly the inlet profile and its turbulence structure...
This paper deals with the diffusion limit of a kinetic equation where the collisions are modeled by a Lorentz type operator. The main aim is to construct a discrete scheme to approximate this equation which gives for any value of the Knudsen number, and in particular at the diffusive limit, the right discrete diffusion equation with the same value of the diffusion coefficient as in the continuous case. We are also naturally interested with a discretization which can be used with few velocity discretization...
This paper deals with the diffusion limit of a kinetic equation where the
collisions are modeled by a Lorentz type operator. The main aim is to construct a
discrete scheme to approximate this equation which gives for any value of the
Knudsen number, and in particular at the diffusive limit, the right discrete
diffusion equation with the same value of the diffusion coefficient as in the
continuous case. We are also naturally interested with a discretization which
can be used with few velocity discretization...
In this work, we are interested in two different diffusion models for multicomponent
mixtures. We numerically recover experimental results underlining the inadequacy of the
usual Fick diffusion model, and the importance of using the Maxwell-Stefan model in
various situations. This model nonlinearly couples the mole fractions and the fluxes of
each component of the mixture. We then consider a subregion of the lower part of the lung,
in which we compare...