HYDRODYNAMICS AND HEAT-TRANSFER IN A VERTICAL CYLINDER EXPOSED TO PERIODICALLY VARYING CENTRIFUGAL FORCES (ACCELERATED CRUCIBLE-ROTATION TECHNIQUE)

Investigations are made of the thermal and hydrodynamic structure of liquid flow in a vertical cylinder exposed to the simultaneous effect of thermal gravitational and periodically varying centrifugal forces. The latter were produced by periodic variation of the rotational speed of the cylinder, the axis of which coincided with that of rotation. A vortex flow is found at the bottom of the cylinder, the direction of which depends on the rotational speed of the latter. The hydrodynamics and heat transfer of the liquid stably stratified over the height and exposed to periodically varying centrifugal forces are investigated. It is shown that there are periodic changes of temperature throughout the entire liquid layer; the values of temperature and velocity and their variations at different liquid layer heights are found. The effect of periodically varying forces on the quality of a growing crystal is analysed. The paper might be of interest for thermal physicists and specialists dealing with the growth of monocrystals. © 1990.