Unsteady Phenomena in the Double-Diffusive Convection Flows at High Rayleigh Number

Abstract

A two-dimensional dual-mesh hybrid numerical method is used to investigate some small scale phenomena in double-diffusive convection flows at high Rayleigh number. With a horizontal temperature gradient, the interface of the two-layer stratified system becomes tilted and wavy, resulting in two typical flow patterns. The quasi-steady flow pattern is scattered with abundant salt fingers and hook-like plumes, which agree well with experimental data available in the literature qualitatively. It is found that three-dimensional modeling should be carried out in order to have better agreement with experimental data. In addition, the stratified system is found to be sensitive to the buoyancy ratio.

The work reported here is supported by the National Science Foundation of China (No. 40476012).