On the effects of a gravitational field on the turbulent transport of heat and momentum

1975 ◽  
Vol 67 (3) ◽  
pp. 569-581 ◽  
Author(s):  
B. E. Launder
Keyword(s):  
Heat Flux ◽  
Gravitational Field ◽  
Shear Flow ◽  
Reynolds Stress ◽  
Turbulent Transport ◽  
Gravitational Effects ◽  
Stratified Shear Flow ◽  
Stably Stratified Shear Flow

This paper suggests a simple way of including gravitational effects in the pres-sure-containing correlations that appear in the equations for the transport of Reynolds stress and heat flux. The predicted changes in structure due to the gravitational field are shown to agree closely with Webster's (1964) measurements in a stably stratified shear flow.

A mathematical model of turbulent heat and mass transfer in stably stratified shear flow

1993 ◽  
Vol 253 (-1) ◽  
pp. 341 ◽  
Author(s):  
G. I. Barenblatt ◽  
M. Bertsch ◽  
R. Dal Passo ◽  
V. M. Prostokishin ◽  
M. Ughi
Keyword(s):  
Mathematical Model ◽  
Mass Transfer ◽  
Shear Flow ◽  
Heat And Mass Transfer ◽  
Turbulent Heat ◽  
Stratified Shear Flow ◽  
Stably Stratified Shear Flow

Turbulence in a Stably Stratified Shear Flow: A Progress Report

1987 ◽  
pp. 67-76 ◽  
Author(s):  
J. J. Rohr ◽  
K. N. Heiland ◽  
E. C. Itsweire ◽  
C. W. Van Atta
Keyword(s):  
Shear Flow ◽  
Progress Report ◽  
Stratified Shear Flow ◽  
Stably Stratified Shear Flow

Entrainment Correlations Based on a Fuel/Water Stratified Shear Flow

2002 ◽  
Author(s):  
Peter A. Chang ◽  
Wesley Wilson ◽  
Paisan Atsavapranee ◽  
Xiongjun Wu ◽  
Joseph Katz
Keyword(s):  
Shear Flow ◽  
Ad Hoc ◽  
Computational Simulation ◽  
Concentration Data ◽  
Buoyant Jets ◽  
Entrainment Velocity ◽  
Fuel Droplets ◽  
Fluid Fraction ◽  
Stratified Shear Flow ◽  
Stably Stratified Shear Flow

The purpose of this work was twofold: first, to develop correlations for the entrainment of small fuel droplets into water in a stratified fuel/water shear flow; second, to implement the correlations in a CFD code and validate it with experimental effluent fuel concentration data. It is assumed that the droplets act as passive scalars and are advected far from their generation regions where they may cause fuel contamination problems far down-stream. This work relied upon extensive experimental data obtained from a stably stratified shear flow: droplet number, droplet PDF, fluid fraction and velocity field data. The droplet data was expressed as a nondimensional entrainment velocity (E) for the volume flux of fuel due to small droplets. The fluid fraction and velocity fields at the interface were expressed in terms of Richardson numbers (Ri). It was found that E = CeRi−n where n = 1 and Ce is a constant, gives a good fit for the two experimental velocity cases. The best correlation was implemented in a computational simulation of the stably stratified shear flow, and the results show that the simulation can predict the entrainment quite well. A second simulation was performed for a flow with energetic vertical buoyant jets (“buoyant flow events”) and stably stratified shear flows with very large Richardson numbers. In this case, the simulations underpredicted effluent fuel concentrations by two orders of magnitude. Ad hoc corrections to the entrainment correlations show marked improvements.

Stably stratified shear flow over low hills

1988 ◽  
Vol 114 (482) ◽  
pp. 859-886 ◽  
Author(s):  
J. C. R. Hunt ◽  
K. J. Richards ◽  
P. W. M. Brighton
Keyword(s):  
Shear Flow ◽  
Stratified Shear Flow ◽  
Stably Stratified Shear Flow

Ground effects on pressure fluctuations in the atmospheric boundary layer

1978 ◽  
Vol 86 (3) ◽  
pp. 491-511 ◽  
Author(s):  
M. M. Gibson ◽  
B. E. Launder
Keyword(s):  
Boundary Layer ◽  
Heat Flux ◽  
Surface Layer ◽  
Atmospheric Surface Layer ◽  
Pressure Field ◽  
Pressure Fluctuations ◽  
Gravitational Effects ◽  
Fluctuating Pressure ◽  
Stratified Shear Flow ◽  
Ground Effects

Proposals are made for modelling the pressure-containing correlations which appear in the transport equations for Reynolds stress and heat flux in a simple way which accounts for gravitational effects and the modification of the fluctuating pressure field by the presence of a wall. The predicted changes in structure are shown to agree with Young's (1975) measurements in a free stratified shear flow and with the Kansas data on the atmospheric surface layer.

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