Abstract
The present Note is a comment on the article “Small and moderate Prandtl number chaotic convection in porous media in the presence of feedback control” by M. N. Mahmud and I. Hashim, published recently online in Transport in Porous Media, doi:10.1007/s11242-009-9511-1. We show that the only effect of the feedback control considered by Mahmud and Hashim is a simple rescaling of the initial conditions of the Vadasz–Olek model which describes the chaotic convection in a porous layer. Thus, the “suppression or enhancement of chaotic convection” found by Mahmud and Hashim as a result of the feedback control, in fact is a manifestation of the famous Butterfly Effect, i.e., a consequence of the high sensitivity of chaotic dynamics with respect to the initial conditions. We also point out in this Note that several results reported by Mahmud and Hashim are in error.
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Magyari, E. The “Butterfly Effect” in a Porous Slab. Transp Porous Med 84, 711–715 (2010). https://doi.org/10.1007/s11242-010-9536-5
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DOI: https://doi.org/10.1007/s11242-010-9536-5