Results 311 to 320 of about 203,668 (343)

Intensity statistics for propagation through a turbulent layer

Applied Optics, 1982
The results of a Monte Carlo calculation of the probability distribution of the far-field irradiance produced by a thin turbulent layer placed in front of a finite-aperture transmitter are discussed. These results clearly show that Rice-Nakagami and other well-known distributions such as the lognormal distribution are inapplicable to this problem.
G C, Valley, W P, Brown
openaire   +2 more sources

The intensity of turbulence in convective clouds

Quarterly Journal of the Royal Meteorological Society, 1957
AbstractCalculations of collision rates between cloud droplets in turbulent air show that this would be an effective precipitation mechanism in cumulus if the r.m.s. turbulent acceleration were about 3 times that due to gravity. An estimated value, based on published records of flights through thunderstorms, is about one‐sixth of gravity.
openaire   +1 more source

Turbulent Intensity Evaluation with PIV

1991
Two velocity components measurements in a turbulent boundary layer have been performed by means of Particle Image Velocimetry (PIV). Multiple images acquisition with a video-camera and successive direct elaboration allow to obtain good statistical evaluations of the quantities which characterize turbulent flows.
A. Cenedese, G. Palmieri, G. P. Romano
openaire   +1 more source

Premixed turbulent flame structures in moderate and intense isotropic turbulence

Combustion Science and Technology, 2002
Several 2-D imaging techniques including planar laser induced fluorescence for OH (OH-PLIF) have been used to investigate premixed turbulent flame structures under moderate to intense isotropic turbulence. Unconditioned velocity statistics were measured by laser Doppler anemometry.
R. K. Cheng, I. G. Shepherd, B. Bédat, L. Talbot   +3 more
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Dynamics of Lean-Premixed Turbulent Combustion at High Turbulence Intensities

Combustion Science and Technology, 2010
Premixed turbulent flames of methane-air stabilized on a Bunsen-type burner were studied to investigate the structure of the flame front at a wide range of turbulence intensities. The nondimensional turbulence rms velocity, rms velocity divided by the laminar flame speed, covered the range from about 3 to 24.
Frank T. C. Yuen, Ömer L. Gülder
openaire   +1 more source

Inertial range scaling of intense events in turbulence

Physical Review E, 1995
The inertial range scaling exponents \ensuremath{\zeta}(p) for the velocity difference moments 〈[u(x+r)-u(x)${]}^{\mathit{p}}$〉 in high Reynolds number turbulence are considered for large values of p. Two different models are considered. In the first the asymptotic behavior of \ensuremath{\zeta}(p) is 1.440${\mathit{p}}^{1/2}$, and in the second it is (
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Relationships between turbulent intensities in turbulent pipe and channel flows

The Aeronautical Journal, 1979
Axial, normal (radial) and tangential turbulence intensity measurements have been carried out in the past in pipe and two-dimensional channel flows, e.g. Refs. 1-9. A similarity in the distribution of these turbulence intensities is observed. They are all minimum at the centreline, increasing steadily as the wall is approached, until they reach some ...
Kaisar Mosa, Mati Alshamani
openaire   +1 more source

Turbulence intensity and turbulent transport characteristics behind gratings in pipes

Fluid Dynamics, 1973
The magnitudes of the variance σ2 of the concentration distribution C(y) of a material being mixed in a stream behind turbulizing gratings in a pipe are measured. The impurity (helium) was inserted in the air stream via a thin pipe mounted directly behind one of the grating orifices.
openaire   +1 more source

The turbulent flame speed for low-to-moderate turbulence intensities

2014
Premixed flame propagation in two-dimensional turbulent flows is examined within the context of a hydrodynamic model. The flame is treated as a surface of density discontinuity and propagates against a turbulent flow of prescribed intensity and scale. A hybrid Navier-Stokes/interface capturing technique is used to describe the flow field throughout the
Moshe Matalon, Navin Fogla, CRETA, Francesco   +2 more
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Numerical study of the effect of turbulence intensity on VAWT performance

Energy, 2021
Marius Paraschivoiu
exaly