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Updated: Aug 27, 2025

The Diffusion of Passive Tracers in Laminar Shear Flow
Published on: May 1, 2018
Inhomogeneous diffusion process in elongated rooms: An interpretation based on the dynamics of sound particles
Cédric Foy1, Vincent Valeau2, Christian Prax2
1UMRAE, CEREMA, Université Gustave Eiffel, IFSTTAR, F-67035 Strasbourg, France.
Abstract:
Previous studies showed that the reverberant field in elongated rooms is governed by non-homogeneous diffusion. The objective of this study is to physically interpret this phenomenon by considering the dynamics of the sound particles. Starting from the original diffusion theory, a quantity that can be interpreted as a "local" mean free path has been proposed and computed from the paths of the propagating particles. Based on the proportionality relationship between the mean free path and the diffusion coefficient, the spatial distribution of the latter could be estimated and successfully compared with a direct estimation using the Fick's law.
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