On the algebraic perturbations in atmospheric boundary layer

A simple model for the development of submesoscale perturbations in the atmospheric boundary layer (ABL) is proposed. The growth of perturbations is associated with the shear algebraic instability of the wind velocity profile in the atmospheric boundary layer (ABL). For the scales of optimal perturbations (streaks) in the lower part of the ABL, estimates of their sizes were obtained about 100-200 m vertically and 300-600 m horizontally. Similar scales are noted for experimental data on the structure of the wind field in the lower part of the ABL, obtained in 2017, 2018 in the summer at the Tsimlyansk Scientific Station at the acoustic sounding of the atmosphere by the Doppler three-component minisodar of high resolution.

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Determination of the Structural Characteristic of the Refractive Index of Optical Waves in the Atmospheric Boundary Layer with Remote Acoustic Sounding Facilities

Atmosphere ◽

10.3390/atmos10110711 ◽

2019 ◽

Vol 10 (11) ◽

pp. 711 ◽

Cited By ~ 1

Author(s):

Odintsov ◽

Gladkikh ◽

Kamardin ◽

Nevzorova

Keyword(s):

Experimental Data ◽

Boundary Layer ◽

Refractive Index ◽

Atmospheric Boundary Layer ◽

Structural Characteristic ◽

Structural Characteristics ◽

Acoustic Sounding ◽

Optical Waves ◽

Ultrasonic Anemometer

The structural characteristic of the refractive index of optical waves was calculated from experimental data on the microstructure of the temperature turbulence in the atmospheric boundary layer. The experimental data were obtained with an acoustic meteorological radar (sodar), ultrasonic anemometer–thermometer, and meteorological temperature profilometer. Estimates of the structural characteristics for different conditions in the atmospheric boundary layer are presented and were compared with model profiles.

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High-Resolution S-Band Profiling of the Atmospheric Boundary Layer

10.21236/ada391934 ◽

2001 ◽

Author(s):

Stephen J. Frasier ◽

Andrew L. Pazmany ◽

Turker Ince

Keyword(s):

Boundary Layer ◽

High Resolution ◽

Atmospheric Boundary Layer

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High-Resolution Properties of the Equatorial Pacific Marine Atmospheric Boundary Layer from Lidar and Radiosonde Observations

Journal of the Atmospheric Sciences ◽

10.1175/1520-0469(1996)053<2054:hrpote>2.0.co;2 ◽

1996 ◽

Vol 53 (14) ◽

pp. 2054-2075 ◽

Cited By ~ 16

Author(s):

D. I. Cooper ◽

W. E. Eichinger ◽

S. Barr ◽

W. Cottingame ◽

M. V. Hynes ◽

...

Keyword(s):

Boundary Layer ◽

High Resolution ◽

Atmospheric Boundary Layer ◽

Equatorial Pacific ◽

Marine Atmospheric Boundary Layer

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An Axial Compressor End-Wall Boundary Layer Calculation Method

Journal of Engineering for Power ◽

10.1115/1.3446474 ◽

1979 ◽

Vol 101 (2) ◽

pp. 233-245 ◽

Cited By ~ 5

Author(s):

J. De Ruyck ◽

C. Hirsch ◽

P. Kool

Keyword(s):

Experimental Data ◽

Boundary Layer ◽

Velocity Profile ◽

Three Dimensional ◽

Axial Compressor ◽

Tip Clearance ◽

Wall Region ◽

Wall Boundary Layer ◽

Wall Boundary ◽

End Wall

An axial compressor end-wall boundary layer theory which requires the introduction of three-dimensional velocity profile models is described. The method is based on pitch-averaged boundary layer equations and contains blade force-defect terms for which a new expression in function of transverse momentum thickness is introduced. In presence of tip clearance a component of the defect force proportional to the clearance over blade height ratio is also introduced. In this way two constants enter the model. It is also shown that all three-dimensional velocity profile models present inherent limitations with regard to the range of boundary layer momentum thicknesses they are able to represent. Therefore a new heuristic velocity profile model is introduced, giving higher flexibility. The end-wall boundary layer calculation allows a correction of the efficiency due to end-wall losses as well as calculation of blockage. The two constants entering the model are calibrated and compared with experimental data allowing a good prediction of overall efficiency including clearance effects and aspect ratio. Besides, the method allows a prediction of radial distribution of velocities and flow angles including the end-wall region and examples are shown compared to experimental data.

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High-resolution simulation of particle transport in the urban atmospheric boundary layer

IOP Conference Series Earth and Environmental Science ◽

10.1088/1755-1315/386/1/012045 ◽

2019 ◽

Vol 386 ◽

pp. 012045

Author(s):

A I Varentsov ◽

V M Stepanenko ◽

P I Konstantinov

Keyword(s):

Boundary Layer ◽

High Resolution ◽

Atmospheric Boundary Layer ◽

Particle Transport ◽

Resolution Simulation

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Velocity Profiles of Turbulent Boundary Layers

The Aeronautical Journal ◽

10.1017/s000192400005329x ◽

1969 ◽

Vol 73 (698) ◽

pp. 143-147 ◽

Cited By ~ 4

Author(s):

M. K. Bull

Keyword(s):

Experimental Data ◽

Boundary Layer ◽

Turbulent Boundary Layer ◽

Velocity Profile ◽

Boundary Layers ◽

Experimental Work ◽

Constant Pressure ◽

Velocity Profiles ◽

Turbulent Boundary Layers ◽

Boundary Layer Equations

Although a numerical solution of the turbulent boundary-layer equations has been achieved by Mellor and Gibson for equilibrium layers, there are many occasions on which it is desirable to have closed-form expressions representing the velocity profile. Probably the best known and most widely used representation of both equilibrium and non-equilibrium layers is that of Coles. However, when velocity profiles are examined in detail it becomes apparent that considerable care is necessary in applying Coles's formulation, and it seems to be worthwhile to draw attention to some of the errors and inconsistencies which may arise if care is not exercised. This will be done mainly by the consideration of experimental data. In the work on constant pressure layers, emphasis tends to fall heavily on the author's own data previously reported in ref. 1, because the details of the measurements are readily available; other experimental work is introduced where the required values can be obtained easily from the published papers.

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Acoustic sounding of the atmospheric boundary layer at Halley, Antarctica

Antarctic Science ◽

10.1017/s0954102089000544 ◽

1989 ◽

Vol 1 (4) ◽

pp. 363-372 ◽

Cited By ~ 12

Author(s):

Alistair D. Culf

Keyword(s):

Boundary Layer ◽

Atmospheric Boundary Layer ◽

Surface Wind ◽

Gravity Currents ◽

Wind Regime ◽

Acoustic Sounding ◽

Use Of Data

The records obtained from a monostatic acoustic sounder run at Halley, Antarctica, have been analysed with the use of data from instruments on a 32 m mast and from radiosonde ascents. Echoes representing ground-based layers, waves, and shallow gravity currents are discussed. The spiky ground-based echo is related to a westerly surface wind, whilst a layered wavy flow is related to surface easterlies. Such relationships are consistent with the sloped inversion wind regime at Halley.

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