1. Numerical simulation of general flow features in a germanium floating zone
- Author
-
K. Lin, P. Dold, and Klaus-Werner Benz
- Subjects
Convection ,Marangoni effect ,Buoyancy ,General Computer Science ,Computer simulation ,Chemistry ,Prandtl number ,Flow (psychology) ,General Physics and Astronomy ,General Chemistry ,Mechanics ,engineering.material ,Physics::Fluid Dynamics ,Computational Mathematics ,symbols.namesake ,Classical mechanics ,Flow velocity ,Mechanics of Materials ,Free surface ,symbols ,engineering ,Astrophysics::Solar and Stellar Astrophysics ,General Materials Science ,Physics::Atmospheric and Oceanic Physics - Abstract
We present a numerical investigation of general flow features in a Ge floating zone, which was performed by using a commercial finite element program FIDAD™. The results demonstrate that for fluids with a very small Pr number the influence of buoyancy forces cannot be ignored in a numerical model. The transition of a steady axisymmetric flow to a time-dependent flow in the Ge floating zone (Ma = 125 and Pr = 0.007) can be clearly attributed to the interaction between the buoyancy flow and the surface flow. The time-dependent buoyancy–thermocapillary convection was purely hydrodynamical. The thermocapillary convection causes an increase of the average flow velocity from 4.07 cm/s to 5.07 cm/s. Due to the small Marangoni and Prandtl numbers as well as the stabilization effect of the buoyancy convection, the temperature fluctuations were smaller than 1 °C in the melt and 2 °C at the free surface.
- Published
- 2007