Thermoelectric Magnetohydrodynamic Flows During Various Crystal Growth Processes With an Externally Applied Magnetic Field

All the models involve a radially outward flow near the crystal-melt interface which helps produce uniform and homogeneous crystals. Numerical results are presented for Bridgman and float zone processes with strong fields. The azimuthal motion dominates the melt motion. As the magnetic field strength is increased from zero to large values, the azimuthal and meridional motions first increase from zero to maxima and then decay back toward zero for very strong magnetic fields. Numerical results for traveling heater method are presented for arbitrary strength magnetic fields. The flow is inertialess at the beginning and the convective effects emerge as the Reynolds number Re is increased for a particular case. For relatively weak magnetic field strength, the convective effects dominate the EM damping effects for very large Re. For weak magnetic field case, the convective effects emerge as thermoelectric body force is increased, and they dominate the melt motion for strong body force. A similarity problem is considered to understand the insights for weak magnetic field case. The solutions reflect the numerical results for weak field cases. While strong magnetic field results are useful for terrestrial crystal growth processes, the arbitrary strength field and weak field results will be useful for future crystal growth experiments in space.

Name thesis:degree_name

Ph.D.

Level thesis:degree_level

Dissertation

Discipline thesis:degree_discipline

Mechanical Engineering

Grantor

University of Illinois at Urbana-Champaign

Year dc:date

2015

Author dc:creator

• Khine, Yu Yu

Contributors dc:contributor

• Walker, J.S.

• Engineering, Chemical

Language dc:language

eng

Identifier

(MiAaPQ)AAI9953064

OAI identifier oai:identifier

oai:www.ideals.illinois.edu:2142/83992