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The interference of two passive scalars in a homogeneous isotropic turbulent field

Published online by Cambridge University Press:  26 April 2006

H. Kaplan  and
N. Dinar
H. Kaplan
Affiliation:
Israel Institute for Biological Research, Ness-Ziona 70450, Israel
N. Dinar
Affiliation:
Israel Institute for Biological Research, Ness-Ziona 70450, Israel
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Abstract

In this work, we study the interference of two scalars diffusing in homogeneous isotropic turbulence. We use the method described by Kaplan & Dinar (1988b) to calculate the cross-correlation coefficient ρ between the concentration fluctuations of two sources. The dependence of ρ on the source separation, shapes and sizes, and its time evolution is calculated for different points in space. Results for the case of two line sources are compared with data from wind tunnel experiments (Warhaft 1984), and seen to be in good agreement. At the centreline ρ is shown to increase as overlap of the two plumes increases. ρ may be either negative or positive depending on the separation between the two sources.

Type
Research Article
Information
Journal of Fluid Mechanics , Volume 203 , June 1989 , pp. 273 - 287
Copyright
© 1989 Cambridge University Press

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