Double-diffusive convection in narrow-aspect cylinders -- experimental data and CFD simulations

An experimental and numerical investigation has been conducted on the evolution of double-diffusive convection in a narrow-aspect cylinder in the diffusive regime in which the cylinder is subjected to bottom and side-wall heating. The laboratory experiments included filling of a narrow aspect ratio tank with linearly stratified salt-water solution. This fluid of known stratification was heated from the side and the bottom to form multiple mixed layers of fluid separated by diffusive interfaces. A micro conductivity and temperature probe was used to obtain the measurements of salinity and temperature and to discern the location of the interfaces. These results are compared to the case of bottom heating only. The numerical simulations have been performed with the FLUENT computational fluid dynamics (CFD) code. Laminar and turbulent simulations have been conducted for one of the experiments. Comparison of laboratory and numerical results shows reasonable agreement.