Temporal dynamics of longitudinal and transverse velocity structure functions retrieved from the data of acoustic sounding

2011 ◽  
Vol 54 (1) ◽  
pp. 113-120 ◽  
Author(s):  
K. H. Underwood ◽  
L. G. Shamanaeva
Keyword(s):  
Velocity Structure ◽  
Temporal Dynamics ◽  
Transverse Velocity ◽  
Structure Functions ◽  
Acoustic Sounding

scholarly journals Calculations of longitudinal and transverse velocity structure functions using a vortex model of isotropic turbulence

1999 ◽  
Vol 11 (12) ◽  
pp. 3743-3748 ◽  
Author(s):  
Guowei He ◽  
Gary D. Doolen ◽  
Shiyi Chen
Keyword(s):  
Velocity Structure ◽  
Isotropic Turbulence ◽  
Transverse Velocity ◽  
Structure Functions ◽  
Vortex Model

Fourth-order moments of longitudinal- and transverse-velocity structure functions

1997 ◽  
Vol 37 (2) ◽  
pp. 85-90 ◽  
Author(s):  
R. A Antonia ◽  
M Ould-Rouis ◽  
Y Zhu ◽  
F Anselmet
Keyword(s):  
Fourth Order ◽  
Velocity Structure ◽  
Transverse Velocity ◽  
Structure Functions

Temporal dynamics of vertical profiles of the velocity structure functions in the lower atmosphere

2012 ◽  
Author(s):  
P. G. Stafeev ◽  
O. F. Kapegesheva ◽  
N. P. Krasnenko ◽  
L. G. Shamanaeva
Keyword(s):  
Velocity Structure ◽  
Temporal Dynamics ◽  
Structure Functions ◽  
Lower Atmosphere ◽  
Vertical Profiles

Longitudinal and transverse structure functions in a turbulent round jet: effect of initial conditions and Reynolds number

2001 ◽  
Vol 436 ◽  
pp. 231-248 ◽  
Author(s):  
G. P. ROMANO ◽  
R. A. ANTONIA
Keyword(s):  
Reynolds Number ◽  
Large Scale ◽  
Velocity Structure ◽  
Initial Conditions ◽  
Transverse Velocity ◽  
Structure Functions ◽  
Small Scale ◽  
Round Jet ◽  
Jet Nozzle ◽  
The Difference

The difference between scaling exponents of longitudinal and transverse velocity structure functions in the far-field of a round jet is found to depend on the anisotropy of the flow. The effect of the large-scale anisotropy is assessed by considering different initial conditions at the jet nozzle, and hence different ratios of the longitudinal to transverse rms velocities. The effect of the Taylor microscale Reynolds number on the small scale anisotropy is also considered. Both effects account, to a large extent, for the observed difference between longitudinal and transverse exponents and the disagreement between previously published results of different authors. This disagreement also depends on the method used to determine the inertial range. An empirical description of the overall behaviour of the structure functions provides reasonable estimates for the longitudinal and transverse exponents, accounting reasonably well for the anisotropy of both large- and small-scale motions.

Scaling of mixed longitudinal-transverse velocity structure functions

2007 ◽  
Vol 79 (4) ◽  
pp. 44001 ◽  
Author(s):  
G Xu ◽  
R. A Antonia ◽  
S Rajagopalan
Keyword(s):  
Velocity Structure ◽  
Transverse Velocity ◽  
Structure Functions

scholarly journals Calculation of velocity structure functions for vortex models of isotropic turbulence

1996 ◽  
Vol 8 (11) ◽  
pp. 3072-3084 ◽  
Author(s):  
P. G. Saffman ◽  
D. I. Pullin
Keyword(s):  
Velocity Structure ◽  
Isotropic Turbulence ◽  
Structure Functions

Low-order velocity structure functions in relatively high Reynolds number turbulence

1999 ◽  
Vol 48 (2) ◽  
pp. 163-169 ◽  
Author(s):  
R. A Antonia ◽  
B. R Pearson
Keyword(s):  
Reynolds Number ◽  
High Reynolds Number ◽  
Velocity Structure ◽  
Structure Functions ◽  
High Reynolds ◽  
Low Order

scholarly journals Scaling and Similarity of the Anisotropic Coherent Eddies in Near-Surface Atmospheric Turbulence

2018 ◽  
Vol 75 (3) ◽  
pp. 943-964 ◽  
Author(s):  
Khaled Ghannam ◽  
Gabriel G. Katul ◽  
Elie Bou-Zeid ◽  
Tobias Gerken ◽  
Marcelo Chamecki
Keyword(s):  
Scaling Laws ◽  
Velocity Structure ◽  
Scaling Law ◽  
Longitudinal Velocity ◽  
Structure Functions ◽  
Length Scale ◽  
Near Surface ◽  
Vegetation Canopies ◽  
Velocity Spectra ◽  
Attached Eddies

Abstract The low-wavenumber regime of the spectrum of turbulence commensurate with Townsend’s “attached” eddies is investigated here for the near-neutral atmospheric surface layer (ASL) and the roughness sublayer (RSL) above vegetation canopies. The central thesis corroborates the significance of the imbalance between local production and dissipation of turbulence kinetic energy (TKE) and canopy shear in challenging the classical distance-from-the-wall scaling of canonical turbulent boundary layers. Using five experimental datasets (two vegetation canopy RSL flows, two ASL flows, and one open-channel experiment), this paper explores (i) the existence of a low-wavenumber k−1 scaling law in the (wind) velocity spectra or, equivalently, a logarithmic scaling ln(r) in the velocity structure functions; (ii) phenomenological aspects of these anisotropic scales as a departure from homogeneous and isotropic scales; and (iii) the collapse of experimental data when plotted with different similarity coordinates. The results show that the extent of the k−1 and/or ln(r) scaling for the longitudinal velocity is shorter in the RSL above canopies than in the ASL because of smaller scale separation in the former. Conversely, these scaling laws are absent in the vertical velocity spectra except at large distances from the wall. The analysis reveals that the statistics of the velocity differences Δu and Δw approach a Gaussian-like behavior at large scales and that these eddies are responsible for momentum/energy production corroborated by large positive (negative) excursions in Δu accompanied by negative (positive) ones in Δw. A length scale based on TKE dissipation collapses the velocity structure functions at different heights better than the inertial length scale.

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