The turbulent diffusion of a passive scalar quantity
Abstract
Consideration is given to the dispersion of a passive contaminant in a turbulent flow. An equation relating the turbulent diffusion flux in the absence of molecular diffusion to the velocity distribution is obtained from the instantaneous turbulent transport equation, and the closure of the equation by a gradient law and a law of the second order in mean concentration is examined for the case of homogeneous turbulence. It is shown that the gradient law requires a Gaussian velocity field, while the more general secondorder law is capable of taking into account velocity asymmetries.
 Publication:

Academie des Sciences Paris Comptes Rendus Serie B Sciences Physiques
 Pub Date:
 March 1980
 Bibcode:
 1980CRASB.290..195M
 Keywords:

 Contaminants;
 Fluid Mechanics;
 Turbulent Diffusion;
 Turbulent Flow;
 Formalism;
 Normal Density Functions;
 Velocity Distribution;
 Fluid Mechanics and Heat Transfer