Verification of the boundary condition at the porous medium–fluid interface

¹ Perm State University, Theoretical Physics Department, 614990 Perm, Bukirev 15 street, Russia
² Perm State University, General Physics Department, 614990 Perm, Bukirev 15 street, Russia
³ Institute of Continuous Media Mechanics UB RAS, CFD Laboratory, 614013 Perm, Acad. Korolev 1 street, Russia

^a e-mail: kbtsiberkin@psu.ru

Published online: 28 March 2016

Abstract

We study the hydrodynamic stability of liquid flowing down over the inclined layer of uniform porous medium and compare the results obtained in the different frameworks. The flow in porous medium is described by the Brinkman model and by the Darcy model with corresponding boundary conditions at the interface between the homogeneous fluid and porous medium. It is shown the critical Reynolds number is calculated for the Darcy model much lower than in case of the Brinkman model, while the flow velocity is the same in the both models. It is a pure mathematical effect, which can be used to verify the models and to determine the empirical coefficients in the boundary conditions from an experimental study of flow instability.