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An Experimental Study of the Effects of A Rotating Magnetic Field on Electrically Conducting Aqueous SolutionsThe use of a rotating magnetic field for stirring metallic melts has been a commonly adopted practice for a fairly long period. The elegance of the technique stems from its non-intrusive nature and the intense stirring it can produce in an electrically conducting medium. A further application of the method in recent times has been in the area of crystal growth from melts (e.g. germanium). The latter experiments have been mainly research oriented in order to understand the basic physics of the process and to establish norms for optimizing such a technique for the commercial production of crystals. When adapted for crystal growth applications, the rotating magnetic field is used to induce a slow flow or rotation in the melt which in effect significantly curtails temperature field oscillations in the melt. These oscillations are known to cause dopant striations and thereby inhomogeneities in the grown crystal that essentially degrades the crystal quality. The applied field strength is typically of the order of milli-Teslas with a frequency range between 50-400 Hz. In this investigation, we report findings from experiments that explore the feasibility of applying a rotating magnetic field to aqueous salt solutions, that are characterized by conductivities that are several orders of magnitude smaller than semi-conductor melts. The aim is to study the induced magnetic field and consequently the induced flow in such in application. Detailed flow field description obtained through non-intrusive particle displacement tracking will be reported along with an analytical assessment of the results. It is anticipated that the obtained results will facilitate in establishing a parameter range over which the technique can be applied to obtain a desired flow field distribution. This method can find applicability in the growth of crystals from aqueous solutions and give an experimenter another controllable parameter towards improving the quality of the grown crystal.
Document ID
19990078601
Acquisition Source
Marshall Space Flight Center
Document Type
Reprint (Version printed in journal)
Authors
Ramachandran Narayanan
(Universities Space Research Association Huntsville, AL United States)
Mazuruk, Konstantin
(Universities Space Research Association Huntsville, AL United States)
Date Acquired
August 19, 2013
Publication Date
January 1, 1998
Subject Category
Fluid Mechanics And Heat Transfer
Meeting Information
Meeting: Microgravity Sciences
Location: Tokyo
Country: Japan
Start Date: July 8, 1998
End Date: July 11, 1998
Funding Number(s)
CONTRACT_GRANT: NCC8-66
Distribution Limits
Public
Copyright
Other

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