scholarly journals Measurement of Atmospheric Turbulence by 2-μm Doppler Lidar

2005 ◽  
Vol 22 (11) ◽  
pp. 1733-1747 ◽  
Author(s):  
Igor Smalikho ◽  
Friedrich Köpp ◽  
Stephan Rahm
Keyword(s):  
Velocity Structure ◽  
Energy Dissipation Rate ◽  
Doppler Spectrum ◽  
Turbulence Energy ◽  
Doppler Lidar ◽  
Coherent Doppler Lidar ◽  
Turbulence Energy Dissipation ◽  
Spectrum Width ◽  
Velocity Structure Function ◽  
Theoretical Results

Abstract Two methods for the estimation of the turbulence energy dissipation rate (TEDR) from data measured by a 2-μm coherent Doppler lidar are described in this paper. Based on data measured at the Tarbes-Lourdes-Pyrénées International Airport in summer 2003, height profiles of TEDR have been retrieved. The results of TEDR estimation both from the Doppler spectrum width and from the velocity structure function are compared. Moreover, the experiment has been treated by numerical simulation and the theoretical results have been used for verification of the described methods.

scholarly journals Effect of Wind Transport of Turbulent Inhomogeneities on Estimation of the Turbulence Energy Dissipation Rate from Measurements by a Conically Scanning Coherent Doppler Lidar

2020 ◽  
Vol 12 (17) ◽  
pp. 2802
Author(s):  
Igor N. Smalikho ◽  
Viktor A. Banakh
Keyword(s):  
Energy Dissipation ◽  
Dissipation Rate ◽  
Sonic Anemometer ◽  
Scanning Speed ◽  
Turbulent Energy ◽  
Energy Dissipation Rate ◽  
Stream Line ◽  
Turbulence Energy ◽  
Doppler Lidar ◽  
Coherent Doppler Lidar

A method for estimation of the turbulent energy dissipation rate from measurements by a conically scanning pulsed coherent Doppler lidar (PCDL), with allowance for the wind transport of turbulent velocity fluctuations, has been developed. The method has been tested in comparative atmospheric experiments with a Stream Line PCDL (Halo Photonics, Brockamin, Worcester, United Kingdom) and a sonic anemometer. It has been demonstrated that the method provides unbiased estimates of the dissipation rate at arbitrarily large ratios of the mean wind velocity to the linear scanning speed.

Doppler lidar alerting algorithm of low-level turbulence based on velocity structure function

2017 ◽  
Vol 46 (10) ◽  
pp. 1030005
Author(s):  
熊兴隆 Xiong Xinglong ◽  
韩永安 Han Yong′an ◽  
蒋立辉 Jiang Lihui ◽  
陈柏纬 Chen Bowei ◽  
陈 星 Chen Xing
Keyword(s):  
Structure Function ◽  
Velocity Structure ◽  
Doppler Lidar ◽  
Low Level ◽  
Velocity Structure Function

Estimating Spatial Velocity Statistics with Coherent Doppler Lidar

2002 ◽  
Vol 19 (3) ◽  
pp. 355-366 ◽  
Author(s):  
Rod Frehlich ◽  
Larry Cornman
Keyword(s):  
Radial Velocity ◽  
Spatial Scales ◽  
Energy Dissipation Rate ◽  
Doppler Lidar ◽  
Wind Fields ◽  
Velocity Statistics ◽  
Coherent Doppler Lidar ◽  
Spatial Velocity ◽  
Large Measurement ◽  
Turbulent Velocity Field

Abstract The spatial statistics of a simulated turbulent velocity field are estimated using radial velocity estimates from simulated coherent Doppler lidar data. The structure functions from the radial velocity estimates are processed to estimate the energy dissipation rate ε and the integral length scale Li, assuming a theoretical model for isotropic wind fields. The performance of the estimates are described by their bias, standard deviation, and percentiles. The estimates of ε2/3 are generally unbiased and robust. The distribution of the estimates of Li are highly skewed; however, the median of the distribution is generally unbiased. The effects of the spatial averaging by the atmospheric movement transverse to the lidar beam during the dwell time of each radial velocity estimate are determined, as well as the error scaling as a function of the dimensions of the total measurement region. Accurate estimates of Li require very large measurement domains in order to observe a large number of independent samples of the spatial scales that define Li.

Sensitizing the Dissipation Equation to Irrotational Strains

1980 ◽  
Vol 102 (1) ◽  
pp. 34-40 ◽  
Author(s):  
K. Hanjalic´ ◽  
B. E. Launder
Keyword(s):  
Energy Transfer ◽  
Energy Dissipation ◽  
Boundary Layers ◽  
Dissipation Rate ◽  
Energy Dissipation Rate ◽  
Turbulent Boundary Layers ◽  
Turbulence Energy ◽  
Turbulence Energy Dissipation ◽  
Dissipation Equation

The paper recommends the addition of an extra term to the conventional approximate transport equation for the turbulence energy dissipation rate. The term may be interpreted as emphasizing the role of irrotational deformations in promoting energy transfer across the spectrum or, equivalently, of augmenting the influence of normal strains. Calculations, including the new term, are reported for the plane and round jet, and for several turbulent boundary layers. In the cases considered the addition of the new term significantly improves agreement with experiment.

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