Lagrangian similarity hypothesis applied to diffusion in turbulent shear flow

1964 ◽  
Vol 11 (4) ◽  
pp. 658
Keyword(s):  
Shear Flow ◽  
Turbulent Shear ◽  
Turbulent Shear Flow ◽  
Similarity Hypothesis

Lagrangian similarity hypothesis applied to diffusion in turbulent shear flow

1963 ◽  
Vol 15 (1) ◽  
pp. 49-64 ◽  
Author(s):  
J. E. Cermak
Keyword(s):  
Boundary Layer ◽  
Surface Layer ◽  
Shear Flow ◽  
Turbulent Shear ◽  
Solid Boundary ◽  
Turbulent Shear Flow ◽  
Mean Velocity ◽  
Similarity Hypothesis ◽  
Neutral Boundary Layer ◽  
Continuous Point

The concept suggested by Batchelor that motion of a marked particle in turbulent shear flow may be similar at stations downstream from the point of release is applied to a variety of diffusion data obtained in the laboratory and in the surface layer of the atmosphere. Two types of shear flow parallel to a plane solid boundary are considered. In the first case mean velocity is a linear function of logz(neutral boundary layer) and in the second case the mean velocity is slightly perturbed from the logarithmic relationship by temperature variation in thez-direction (diabatic boundary layer). Besides the parameters introduced in previous applications of the Lagrangian similarity hypothesis to turbulent diffusion, the ratio of source height to roughness lengthh/z0is shown to be of major importance. Predictions of the variation of maximum ground-level concentration for continuous point and line sources and the variation of plume width for a continuous point source with distance downstream from the source agree with the assorted data remarkably well for a range of length scales extending over three orders-of-magnitude. It is concluded that results from application of the Lagrangian similarity hypothesis are significant for the laboratory modelling of diffusion in the atmospheric surface layer.

Open-loop control of compensation for optical propagation through a turbulent shear flow

1998 ◽  
Author(s):  
C. Truman ◽  
Lenore McMackin ◽  
Robert Pierson ◽  
Kenneth Bishop ◽  
Ellen Chen
Keyword(s):  
Shear Flow ◽  
Open Loop ◽  
Turbulent Shear ◽  
Turbulent Shear Flow ◽  
Open Loop Control ◽  
Loop Control ◽  
Optical Propagation

scholarly journals Scale dependence of the alignment between strain rate and rotation in turbulent shear flow

2016 ◽  
Vol 1 (6) ◽  
Author(s):  
D. Fiscaletti ◽  
G. E. Elsinga ◽  
A. Attili ◽  
F. Bisetti ◽  
O. R. H. Buxton
Keyword(s):  
Shear Flow ◽  
Strain Rate ◽  
Scale Dependence ◽  
Turbulent Shear ◽  
Turbulent Shear Flow

The structure of turbulent shear flow

1980 ◽  
Vol 70 (1-2) ◽  
pp. 187-188
Author(s):  
F.H. Busse
Keyword(s):  
Shear Flow ◽  
Turbulent Shear ◽  
Turbulent Shear Flow

Effects of turbulent shear flow on zooplankton distribution

1990 ◽  
Vol 37 (3) ◽  
pp. 447-461 ◽  
Author(s):  
Loren R. Haury ◽  
Hidekatsu Yamazaki ◽  
Eric C. Itsweire
Keyword(s):  
Shear Flow ◽  
Turbulent Shear ◽  
Turbulent Shear Flow ◽  
Zooplankton Distribution

scholarly journals MAGNETIC RESONANCE SIGNAL LOSS IN TURBULENT SHEAR FLOW

2002 ◽  
Vol 14 (01) ◽  
pp. 1-11
Author(s):  
LIANG-DER JOU
Keyword(s):  
Shear Flow ◽  
Velocity Fluctuation ◽  
Phase Fluctuation ◽  
Eddy Diffusivity ◽  
Turbulent Shear ◽  
Turbulent Shear Flow ◽  
Signal Loss ◽  
Flow Shear ◽  
Magnetic Gradient ◽  
Spin Echo Sequence

NMR signal loss due to turbulent shear flow is discussed, and a general expression for the phase fluctuation is derived. In the presence of flow shear, the velocity fluctuation perpendicular to the direction of magnetic gradient and the Reynolds stress can cause loss of MR signal Most of signal loss results from the boundary layer, where the flow shear is strong in turbulent pipe flaw, Half the signal loss within the mixing layer distal to a moderate stenosis is caused by the velocity fluctuation in the direction of magnetic gradient, while the remaining results from the velocity, fluctuation perpendicular to the magnetic gradient. The use of eddy diffusivity for the description of signal dephasing in a spin echo sequence is also addressed; A positive, constant eddy diffusivity can not describe the temporal change of phase fluctuation correctly.

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