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A stochastic model for dispersion and concentration distribution in homogeneous turbulence

Published online by Cambridge University Press:  21 April 2006

H. Kaplan
Affiliation:
Israel Institute for Biological Research, P.O. Box 19, Ness-Ziona 70450, Israel
N. Dinar
Affiliation:
Israel Institute for Biological Research, P.O. Box 19, Ness-Ziona 70450, Israel

Abstract

A new approach to contaminant diffusion in homogeneous turbulence is proposed. This approach is based on solving for the Lagrangian trajectories of many particles taking into account the interaction among their velocities. The velocity field at a given instant is composed of many ‘eddies’ distributed randomly and uniformly in space. The velocity of each eddy is proportional to the cube root of its size. In this way the calculated Eulerian correlation function between any two points is consistent with observations. The present model is used to calculate concentration fluctuations, concentration averages and intermittency as functions of location and time. Results were found to be in accordance with experimental measurements. Probability distributions as functions of time and location are also calculated.

Type
Research Article
Copyright
© 1988 Cambridge University Press

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