Modeling of Mixing by Turbulent Jet in Stably Stratified Fluid
Publication: Journal of Hydraulic Engineering
Volume 121, Issue 12
Abstract
A model that describes the density-profile evolution in a confined region with a stably stratified fluid, where mixing is induced by a circular, nonswirling turbulent jet discharged vertically down into the fluid is presented here. The interaction between the downward-moving jet and a resulting rising plume is modeled through a coupled system of equations that encompasses integral equations for volume, momentum, and buoyancy conservation for the jet and plume, respectively. A schematized flow pattern in the ambient fluid is employed to determine the effect of the jet/plume mixing on the density-profile evolution, and a diffusion equation is used to describe additional mixing processes in the ambient fluid outside the jet/plume region. The model is validated with experimental data on the density-profile evolution in a rectangular container produced by a mixing jet, and the calculations compare favorably with data for higher values on the densimetric Froude number. The mixing is underestimated for lower values on the Froude number.
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Copyright © 1995 American Society of Civil Engineers.
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Published online: Dec 1, 1995
Published in print: Dec 1995
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