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On vortex air motions above an axisymmetric source of mass, momentum and heat

Published online by Cambridge University Press:  26 April 2006

Y. A. Berezin  and
K. Hutter
Y. A. Berezin
Affiliation:
Institute for Theoretical and Applied Mechanics, Novosibirsk 630090, Russia
K. Hutter
Affiliation:
Institute for Theoretical and Applied Mechanics, Novosibirsk 630090, Russia Institut für Mechanik, Technische Hochshule, 64289 Darmstadt, Germany
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Abstract

We study axisymmetric plume dispersion from a steady source of mass, momentum and/or heat that is subjected to either a time-dependent large-scale external vortex or small-scale turbulent axisymmetric helicity. On the basis of the turbulent boundary layer and Boussinesq assumptions and by assuming similarity profiles with Gaussian distribution in the radial direction the balance equations of mass, momentum, and energy reduce to a system of nonlinear differential equations for amplitude functions of axial velocity, pressure and density differences as well as azimuthal velocity. The system of equations is closed with Taylor's entrainment assumption.

The plume radius and the typical radius of the large-scale external vortex are also determined. For a simple density structure of the ambient atmosphere (i.e. adiabatic conditions) analytical results can be obtained, but for more complicated cases, i.e. a layered polytropic atmosphere, the governing equations are examined numerically; computations are reasonably simple and efficient.

Type
Research Article
Information
Journal of Fluid Mechanics , Volume 290 , 10 May 1995 , pp. 299 - 317
Copyright
© 1995 Cambridge University Press

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