Structure of Sidewall Thermoconcentration Convection in the Flow Formation and Disintegration Regimes

Abstract

The transformation of the structure of the density, optical refractive index, temperature, and salinity fields in the regimes of formation and disintegration of convection flows under uniform sidewall cooling of a continuously stratified fluid is investigated using optical and probe techniques. Although the height of the individual cells is almost constant in the various stages of the process, the field patterns change significantly. In the formation stage the contributions of the temperature and salinity to the density distribution compensate each other, the density profile is smooth and the optical refractive index profile is stepped. In the disintegration stage the density profile also becomes stepped. At large times a new convection flow is formed on the external boundaries of the cells due to the temperature difference between the cooled inner fluid and the warmer outer (undisturbed) fluid, and this flow maintains the structure contrast as the motion degenerates.