Hydrodynamic simulation of forced convection in Czochralski melts
Abstract
Systematic hydrodynamic simulation experiments at room temperature were carried out in order to enhance the understanding of flow phenomena in Czochralski melts. An apparatus has been designed which allows the (three-dimensional) observation of hydrodynamic effects for various crucible shapes with adjustable rotation rates for crystal and crucible for iso- and counter-rotation. Also the effect of the accelerated crucible (and crystal) rotation technique (ACRT) on melt homogenization can be investigated. Flow visualization and measurement was done by ink injection, by light scattering of suspended particles and by the Schlieren technique, and laser doppler anemometry is foreseen. In this first report the results on forced convection in Czochralski melts and the occurrence ranges of specific flow regimes (like Cochran and Ekman flow, Couette and Taylor cells) and the transition from stable mixing to flow instability are discussed.
- Publication:
-
Journal of Crystal Growth
- Pub Date:
- December 1984
- DOI:
- 10.1016/0022-0248(84)90246-X
- Bibcode:
- 1984JCrGr..70...49R