A Kinematic Eddy Viscosity Model including the Influence of Density Variations and Preturbulence
نویسنده
چکیده
A model for the kinematic eddy viscosity has been developed which accounts for the turbulence produced as a result of jet interactions between adjacent streams as well as the turbulence initially present in the streams. In order to describe the turbulence contribution from jet interaction, the eddy viscosity suggested by Prandtl has been adopted, and a modification has been introduced to account for the effect of density variation through the mixing layer. The form of the modification was ascertained from a study of the compressible turbulent boundary layer on a flat plate. A kinematic eddy viscosity relation which corresponds to the initial turbulence contribution has been derived by employing arguments used by Prandtl in his mixing length hypothesis. The resulting expression for self-preserving .flow is similar to that which describes the mixing of a submerged jet.
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