Results 251 to 260 of about 10,202,208 (291)

Cross beam scintillations in non-Kolmogorov medium

Journal of the Optical Society of America A, 2014
For the collimated and focused cross beams, the on-axis scintillation index is evaluated when these beams propagate in weak non-Kolmogorov turbulence. In the limiting cases, our solution correctly reduces to the known Gaussian beam scintillations in Kolmogorov turbulence.
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Multicomponent turbulence, the spherical limit, and non-Kolmogorov spectra

Physical Review E, 1995
A set of models for homogeneous, isotropic turbulence is considered in which the Navier-Stokes equations for incompressible fluid flow are generalized to a set of N coupled equations in N velocity fields. It is argued that in order to be useful these models must embody a new group of symmetries, and a general formalism is laid out for their ...
, Mou, , Weichman
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A General Mathematical Model For Non-Kolmogorov Turbulence

Imaging and Applied Optics, 2013
We present a power spectral density model of index of refraction, including power law relations within finite bands, and impulses denoting energy concentrations. We then discuss some resulting equations, without resorting to Kolmogorov assumptions.
Thomas C Farrell, Darryl I Sanchez, Jason Holzman, Patrick R Kelly   +3 more
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Phase compensation in non-Kolmogorov atmospheric turbulence

Optik, 2014
Abstract Zernike polynomial decompositions are used for investigating phase distortion induced by atmospheric turbulence in optical systems. Closed-form expression of the Zernike-coefficient variances is derived. The finite size of the receiver aperture is analyzed using the filter function which is also particularly effective in the theoretical ...
Hua Tang, Pengzhan Guo
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Optical propagation in non-Kolmogorov atmospheric turbulence

SPIE Proceedings, 1995
Several observations of atmospheric turbulence statistics have been reported which do not obey Kolmogorov's power spectral density model. These observations have prompted the study of optical propagation through turbulence described by non-classical power spectra.
Bruce E. Stribling, Byron M. Welsh, Michael C. Roggemann   +2 more
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Non-Kolmogorov’s and Kolmogorov’s Solitonic Hydrodynamical Turbulence

Imaging and Applied Optics 2014, 2014
The experimental spectrums for the non-Kolmogorov’s and Kolmogorov’s turbulence are presenting as a sums of spectrums of several coherent structures. Therefore the coherent structure (soliton solution of the hydrodynamic equations) is the basic structural element of turbulence.
V.V. Nosov, P.G. Kovadlo, V.P. Lukin, E.V. Nosov, A.V. Torgaev   +4 more
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Imaging and communications through non-Kolmogorov turbulence

SPIE Proceedings, 2009
At present, system design usually assumes the Kolmogorov model of refractive index fluctuation spectra in the atmosphere. However, experimental data indicates that in the atmospheric boundary layer and at higher altitudes the turbulence can be different from Kolmogorov's type.
Norman S. Kopeika, Arkadi Zilberman, Ephim Golbraikh   +2 more
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Non-Kolmogorov dissipation in a turbulent planar jet

Physical Review Fluids, 2018
Adopting Lie symmetry group theory both Kolmogorov and non-Kolmogorov scaling and dissipation laws are explored theoretically for a turbulent planar jet. We find that the jet entrainment coefficient varies with streamwise distance when non-Kolmogorov scaling laws hold.
G. C. Layek, null Sunita
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Karhunen–Loeve functions for non-Kolmogorov turbulence

Journal of Turbulence, 2017
ABSTRACTKarhunen–Loeve functions for the case of non-Kolmogorov turbulence are calculated. The calculations are performed using the covariance matrix of Zernike coefficients which is derived in analytical form. It is shown that the Karhunen–Loeve expansion is more efficient than the Zernike one for simulations of high-order, turbulence-induced phase ...
Valeri Orlov, Valeri Voitsekhovich
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Multimode Laser Beam Scintillations in Non-Kolmogorov Turbulence

IEEE Journal on Selected Areas in Communications, 2015
Employing the Rytov solution, the scintillation index at the origin of the receiver plane is evaluated in non-Kolmogorov weak atmospheric turbulence when multimode laser incidence is used. The solution presented can be used when the multimode is composed of even modes. The novelty of this work lies in the theoretical combination of multimode laser beam
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