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Rotating axial flow of a continuously separating mixture

Published online by Cambridge University Press:  26 April 2006

A. A. Dahlkild  and
G. Amberg
A. A. Dahlkild
Affiliation:
Department of Mechanics, Royal Institute of Technology, 100 44 Stockholm, Sweden
G. Amberg
Affiliation:
Department of Mechanics, Royal Institute of Technology, 100 44 Stockholm, Sweden
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Abstract

We consider the continuous separation process of a monodispersed suspension flowing axially through a rotating circular cylinder. This stationary problem can be regarded as a basic flow case of rotating mixtures in conjunction with previous studies of time-dependent flows like spin-up and batch settling in a cylinder. The ‘mixture model’ for two-phase flow is used to formulate the problem, which is solved in the range of small Ekman and Rossby numbers by asymptotic analytical methods and by a numerical code. The gradual separation of the axially injected suspension is manifested as a stationary stratification of the mixture which induces a swirl component of the velocity, in analogy with the thermal wind in the Earth's atmosphere. The presence of the azimuthal motion and induced secondary flow due to Ekman-layer pumping clearly influences the character of the stratification. Analytical and numerical results are in excellent agreement.

Type
Research Article
Information
Journal of Fluid Mechanics , Volume 266 , 10 May 1994 , pp. 319 - 346
Copyright
© 1994 Cambridge University Press

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