We consider a time-dependent model for the diffusion of a substance through an incompressible fluid in a perforated domain Ω , Ω ⊂ Ω ⊂ R n with n = 3, 4. The fluid flows in a domain containing a periodical set of "obstacles" (Ω∖Ω ) placed along an inner (n − 1)-dimensional manifold Σ ⊂ Ω. The size of the obstacles is much smaller than the size of the characteristic period . An advection term appears in the partial differential equation linking the fluid velocity with the concentration, while we assume a nonlinear adsorption law on the boundary of the obstacles. This law involves a monotone nonlinear function of the concentration and a large adsorption parameter. The "critical adsorption parameter" depends on the size of the obstacles , and, for different sizes, we derive the time-dependent homogenized models. These models contain a "strange term" in the transmission conditions on Σ, which is a nonlinear function and inherits the properties of . The case in which the fluid velocity and the concentration do not interact is also considered for n ≥ 3.
CorrespondenceMaría-Eugenia Pérez-Martínez, ETSI Caminos, Canales y Puertos. Av. de los Castros s/n.,