Effects of g-jitter and Marangoni convection on float zones

Abstract

The effects of £-jitter on three liquid zone experiments are numerically investigated. The g -level used in the study is composed of a steady component, characterizing the residual acceleration environment, and a timevarying component, characterizing the £-jitter environment. The time-varying component is comprised of either a sinusoidal or impulse disturbance. The response of both unencapsulated and encapsulated zone configurations are examined. The results indicate that complex flow patterns can arise that significantly modify the heat transfer characteristics of the system. The effects are more pronounced at the lowest frequency investigated (10 ~3 Hz), and impulsive accelerations imparted to fluids with large Prandtl numbers were found to have long decay times. Detailed velocity, temperature, average Nusselt number, and temperature sensitivity information are presented for many of the cases investigated.