Journal ArticleDOI
Integral Model for Turbulent Buoyant Jets in Unbounded Stratified Flows. Part I: Single Round Jet
TLDR
In this paper, an integral model for the conservation of mass, momentum, buoyancy and scalar quantities in the turbulent jet flow is proposed, which employs an entrainment closure approach that distinguishes between the separate contributions of transverse shear (leading to jet, plume, or wake internal flow dynamics) and of azimuthal shear mechanisms, respectively.Abstract:
The mechanics of buoyant jet flows issuing with a general three-dimensional geometry into an unbounded ambient environment with uniform density or stable density stratification and under stagnant or steady sheared current conditions is investigated. An integral model is formulated for the conservation of mass, momentum, buoyancy and scalar quantities in the turbulent jet flow. The model employs an entrainment closure approach that distinguishes between the separate contributions of transverse shear (leading to jet, plume, or wake internal flow dynamics) and of azimuthal shear mechanisms (leading to advected momentum puff or thermal flow dynamics), respectively. Furthermore, it contains a quadratic law turbulent drag force mechanism as suggested by a number of recent detailed experimental investigations on the dynamics of transverse jets into crossflow. The model is validated in several stages: First, comparison with basic experimental data for the five asymptotic, self-similar stages of buoyant jet flows, i.e., the pure jet, the pure plume, the pure wake, the advected line puff, and the advected line thermal, support the choice and magnitude of the turbulent closure coefficients contained in the entrainment formulation. Second, comparison with many types of non-equilibrium flows support the proposed transition function within the entrainment relationship, and also the role of the drag force in the jet deflection dynamics. Third, a number of spatial limits of applicability have been proposed beyond which the integral model necessarily becomes invalid due to its parabolic formulation. These conditions, often related to the breakdown of the boundary layer nature of the flow, describe features such as terminal layer formation in stratification, upstream penetration in jets opposing a current, or transition to passive diffusion in a turbulent ambient shear flow. Based on all these comparisons, that include parameters such as trajectories, centerline velocities, concentrations and dilutions, the model appears to provide an accurate and reliable representation of buoyant jet physics under highly general flow conditions.read more
Citations
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Journal ArticleDOI
Inclined Negatively Buoyant Discharges
TL;DR: In this article, analytical solutions are developed to predict the behavior of inclined negatively buoyant discharges and these solutions are compared with data from previous studies and from experiments described here, where light attenuation and laser-induced fluorescence techniques are employed to study these flows.
Journal ArticleDOI
Modelling and environmentally sound management of brine discharges from desalination plants
TL;DR: In this paper, the authors examined the effect of flatter discharge angles of about 30° to 45° above horizontal on the performance of CorJet, a jet integral model within the CORMIX expert system.
Journal ArticleDOI
Integral Model for Turbulent Buoyant Jets in Unbounded Stratified Flows Part 2: Plane Jet Dynamics Resulting from Multiport Diffuser Jets
TL;DR: An integral model for the plane buoyant jet dynamics resulting from the interaction of multiple buoyant jets spaced along a diffuser line is considered as an extension of the round jet formulation that was proposed in Part I as discussed by the authors.
Journal ArticleDOI
Mixing and boundary interactions of 30° and 45° inclined dense jets
TL;DR: In this article, the mixing behavior of 60° inclined dense jets discharging at smaller angles of 30° and 45° in a stationary ambient was investigated and the effect of the proximity to the bed was examined.
Journal ArticleDOI
Improved Discharge Configurations for Brine Effluents from Desalination Plants
TL;DR: In this paper, the authors show that flatter discharge angles of about 30-45° above horizontal may have considerable design advantages, especially if bottom slope and port height are taken into account, there is better offshore transport of the mixed effluent during weak ambient current conditions, and there is the ability to locate in more shallow water near shore.
References
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Book
Mixing in Inland and Coastal Waters
TL;DR: In this paper, the concept of Fickian Diffusion and Turbulent Diffusion is used for mixing in rivers and estuaries, and an estimate for the density of seawater is given.
Book
Buoyancy Effects in Fluids
TL;DR: In this article, the authors introduce linear internal waves and herar flows in a stratified fluid and double-diffusive convection in stably stratified fluids, and show that the shear flows can produce turbulence.
Journal ArticleDOI
Turbulent gravitational convection from maintained and instantaneous sources
TL;DR: In this article, the authors developed a theory of convection from maintained and instantaneous sources of buoyancy, using methods which are applicable to stratified body fluids with any variation of density with height; detailed solutions have been presented for the case of a stably stratified fluid with a linear density gradient.
Journal ArticleDOI
Orderly Structure in Jet Turbulence
S. C. Crow,F. H. Champagne +1 more
TL;DR: In this paper, the authors show that a large-scale orderly pattern may exist in the noiseproducing region of a round subsonic jet by observing the evolution of orderly flow with advancing Reynolds number.