Growth rates of the buoyancy-driven instability of an autocatalytic reaction front in a narrow cell
Experimental studies were performed on the buoyancy-driven instability of an autocatalytic reaction front in a quasi-2D cell. The unstable density stratification at an ascending front leads to convection that results in a fingerlike front deformation. The growth rates of the spatial modes of the instability are determined at the initial stage. A stabilization is found at higher wave numbers, while the system is unstable against low wave number perturbations. Whereas comparison with a reported model governed by Hele-Shaw flow fails, a two-dimensional Navier-Stokes model yields more satisfactory results. Still, present deviations suggest the presence of an additional mechanism that suppresses the growth.
Bockmann
M
Institut fur Experimentelle Physik, Otto-von-Guericke-Universitat Magdeburg, PF 4120, D-39016 Magdeburg, Germany.
Muller
SC