Revue des sciences et sciences de l’ingénieur
Volume 5, Numéro 1, Pages 24-30
2015-06-01

Stabilité Magnétique De La Convection De Marangoni Lors De La Croissance Cristalline Par La Technique De Czochralski

Auteurs : Atia A . Bouabdallah, S . Ghernaout B . Benchatti A .

Résumé

The present work deals to the magnetic stability of the Marangoni convection which develops during crystal growth by the Czochralski method. A similar cavity to that of Czochralski of aspect ratio Ar = H/Rc = 2,filled with liquid silicon has been considered. The cavity is laterally heated at Th, and a third of the cover of radius rs (crystal solidifies) is cooled to the temperature Tc. In addition the remainder of the lid is considered as a free surface. The physical system in question is exposed to a uniform external magnetic field applied in the axial direction of the cylinder. The finite volume method was used for the numerical solution of the governing equations. The results obtained are compared with those of the experimental work available in the literature. The effect of Marangoni number on the structure of the flow and the thermal field has been presented and discussed, for Ma = 0, 200, 400, 600, 800 and 1000. The axial magnetic field effect on the stability of the flow is taken into account for Ha = 0, 25, 50, 75 and 100. The obtained results show that the magnetic field applied in the axial direction provides significant changes in the structure of the flow and heat transfer. It causes a reduction in the heat transfer rate and a considerable damping in the velocity field, and therefore stabilizes the Marangoni convection.

Mots clés

Marangoni convection, Magnetic field, Czochralski, Finite volume method.