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Homeotropic nematics heated from above under magnetic fields: convective thresholds and geometry

Published online by Cambridge University Press:  20 April 2006

J. Salan  and
E. Guyon
J. Salan
Affiliation:
E.S.P.C.I., 10 rue Vauquelin, 75005 Paris, France
Also at: Laboratoire de Physique des Solides, Université Paris-Sud, 91405 Orsay.
 Permanent address: Departemento de Física Fundamental, U.N.E.D., Apdo Correos 54487 Madrid 3, Spain.
E. Guyon
Affiliation:
E.S.P.C.I., 10 rue Vauquelin, 75005 Paris, France
Also at: Laboratoire de Physique des Solides, Université Paris-Sud, 91405 Orsay.
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Abstract

The thermal convective instability of a nematic layer aligned perpendicular to horizontal plates displays original characteristics, due to the coupling of the nematic distortion with the temperature gradient; in particular the adverse temperature gradient threshold ΔTc can be modified by the application of a vertical (stabilizing) or horizontal (destabilizing) magnetic field. In addition, the application of a magnetic field H controls both the threshold of this instability and the geometric form of the instabilities above ΔTc.

Type
Research Article
Information
Journal of Fluid Mechanics , Volume 126 , January 1983 , pp. 13 - 26
Copyright
© 1983 Cambridge University Press

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