Concentration-Gradient-Driven Convection: Experiments

Abstract

Concentration-gradient-driven convection was studied by measurement of the rate of dissolution of the lower face of a KCl single crystal in contact with various solvents. The rate of mass transfer due to convective stirring appeared to follow the Rayleigh number to the one-third power law. A regular pattern of etch pits due to the convective stirring action was observed in the crystal face after exposure to water for 5 minutes. Schlieren photographs of the early stages of dissolution showed a regular pattern of spikes having approximately the same dimensions as the etch pits in the crystals.