NPG Nonlinear Processes in Geophysics NPG Nonlin. Processes Geophys. 1607-7946 Copernicus Publications Göttingen, Germany 10.5194/npg-20-543-2013 Stability and nonlinear regimes of flow over a saturated porous medium Lyubimova T. P. 1 2 Baydina D. T. 2 Lyubimov D. V. 2 Institute of Continuous Media Mechanics, Ural Branch of RAS, Perm, Russia Perm State University, Theoretical Physics Department, Perm, Russia 23 07 2013 20 4 543 547 Copyright: © 2013 T. P. Lyubimova et al. 2013 This work is licensed under the Creative Commons Attribution 3.0 Unported License. To view a copy of this licence, visit https://creativecommons.org/licenses/by/3.0/ This article is available from https://npg.copernicus.org/articles/20/543/2013/npg-20-543-2013.html The full text article is available as a PDF file from https://npg.copernicus.org/articles/20/543/2013/npg-20-543-2013.pdf

The paper deals with the investigation of stability and nonlinear regimes of flow over the saturated porous medium applied to the problem of stability of water flow over the bottom covered with vegetation. It is shown that the velocity profile of steady plane-parallel flow has two inflection points, which results in instability of this flow. The neutral stability curves, the dependencies of critical Reynolds number and the wave number of most dangerous perturbations on the ratio of porous layer thickness to the total thickness are obtained. The nonlinear flow regimes are investigated numerically by finite difference method. It is found that at supercritical parameter values waves travelling in the direction of the base flow take place.

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