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The gravitational settling of aerosol particles in homogeneous turbulence and random flow fields

Published online by Cambridge University Press:  21 April 2006

M. R. Maxey
Affiliation:
Division of Applied Mathematics, Brown University, Providence. RI 02912, USA

Abstract

The average settling velocity in homogeneous turbulence of a small rigid spherical particle, subject to a Stokes drag force, is shown to depend on the particle inertia and the free-fall terminal velocity in still fluid. With no inertia the particle settles on average at the same rate as in still fluid, assuming there is no mean flow. Particle inertia produces a bias in each trajectory towards regions of high strain rate or low vorticity, which affects the mean settling velocity. Results from a Gaussian random velocity field show that this produces an increased settling velocity.

Type
Research Article
Copyright
© 1987 Cambridge University Press

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