Numerical Simulation of Thermocapillary-Buoyancy Convection in Detached Solidification

摘要

In order to understand the characteristics of thermocapillary-buoyancy convection in detached solidification, we conducted a series of numerical simulations of thermocapillary flow of CdZnTe melt with different aspect ratio and gap width under gravity using the finite-difference method. The results indicate that, at a small Marangoni number, the buoyancy has a great effect on the temperature distribution; however, its influence on the maximum stream function value is so little that it can be neglected. When Marangoni number exceeds a threshold value, the steady flow converts into the unstable convection. In addition, the buoyancy makes the critical Marangoni numbers decrease by one order of magnitude comparing the results obtained in gravity and those in microgravity condition.