Control of chemo-hydrodynamic pattern formation by external localized coolingD. A. Bratsun1, Y. Shi2, K. Eckert2 and A. De Wit1
1 Service de Chimie Physique and Center for Nonlinear Phenomena and Complex Systems, CP 231, Université Libre de Bruxelles - 1050 Brussels, Belgium
2 Institute for Aerospace Engeneering, Dresden University of Technology 01062 Dresden, Germany
received 27 September 2004; accepted in final form 3 January 2005
published online 2 February 2005
Chemo-hydrodynamic patterns can form in a chemical two-layer system in a Hele-Shaw cell when each fluid contains separately a reactant of an exothermic neutralization reaction. When one reactant diffuses through the interface, the coupling between the chemical reaction and buoyancy-driven flows gives rise to complex spatio-temporal fingering near the interface. We show both experimentally and theoretically that such chemistry-driven fingering and its characteristics can be precisely controlled by external cooling applied locally along the sidewalls of the reactor. This control process gives a bright example of cooperative phenomena between chemistry and hydrodynamics and offers promising technological applications.
47.70.Fw - Chemically reactive flows.
47.70.-n - Reactive, radiative, or nonequilibrium flows.
47.20.Bp - Buoyancy-driven instability.
© EDP Sciences 2005