Origins of features in wave number-frequency spectra of space-time images of the ocean

2012 ◽  
Vol 117 (C6) ◽  
pp. n/a-n/a ◽  
Author(s):  
William J. Plant ◽  
Gordon Farquharson
Keyword(s):  
Space Time ◽  
Wave Number ◽  
Frequency Spectra ◽  
Number Frequency

Turbulence functions useful for probes (space–time correlation) and for scattering (wave-number–frequency spectrum) analysis

1968 ◽  
Vol 46 (23) ◽  
pp. 2683-2702 ◽  
Author(s):  
I. P. Shkarofsky
Keyword(s):  
Characteristic Size ◽  
Time Correlation ◽  
Exponential Model ◽  
Time Correlation Function ◽  
Maximum Energy ◽  
Confluent Hypergeometric Function ◽  
Space Time ◽  
Wave Number ◽  
Taylor’S Hypothesis ◽  
Number Frequency

The wave-number–frequency dependent spectral function, S(k, ω), and the space–time correlation function, C(r, t), are considered in a turbulent flowing plasma. The decay mechanisms are associated with either velocity fluctuations about the mean convection velocity or diffusion effects or attachment, or combinations of these, including the Brownian motion model. The ψ(k, ω) function, which is the ratio of S(k, ω) to its frequency-integrated value, depends on the mechanism and exhibits a profile which can be Gaussian, Lorentzian, a Z function, a Hermite polynomial modification of the Gaussian, or a confluent hypergeometric function. Anisotropic forms are also considered.The function C(r, t), obtained by convolving ψ (r, t) with C(r), the space autocorrelation function, is next considered. Adopting a Gaussian or an exponential model (which may be anisotropic) for C(r), we illustrate C(r, t) forms, which can readily be manipulated. Furthermore, letting r = 0, we derive two conditions for the applicability of Taylor's hypothesis. The assumption of frozen flow is not necessary, only that the root-mean-square Lagrangian displacement in a given time, associated with the decay, be much smaller than both the flow distance and the characteristic size of blobs having maximum energy.

Space-time-wave number-frequency Z(x,t,k,f) analysis of SAW generation on fluid filled cylindrical shells

Ultrasonics ◽  
2004 ◽  
Vol 42 (1-9) ◽  
pp. 383-389 ◽  
Author(s):  
Loı̈c Martinez ◽  
Bruno Morvan ◽  
Jean Louis Izbicki
Keyword(s):  
Cylindrical Shells ◽  
Space Time ◽  
Wave Number ◽  
Number Frequency

Wave number frequency spectra of a lifting wake for broadband noise prediction

AIAA Journal ◽  
1998 ◽  
Vol 36 ◽  
pp. 881-887
Author(s):  
William J. Devenport ◽  
Christian W. Wenger ◽  
Stewart A. Glegg ◽  
Joseph A. Miranda
Keyword(s):  
Broadband Noise ◽  
Wave Number ◽  
Noise Prediction ◽  
Frequency Spectra ◽  
Number Frequency

Deconvolution of Wave-Number-Frequency Spectra of Wall Pressure Fluctuations

AIAA Journal ◽  
2020 ◽  
Vol 58 (1) ◽  
pp. 164-173 ◽  
Author(s):  
Simon L. Prigent ◽  
Édouard Salze ◽  
Christophe Bailly
Keyword(s):  
Pressure Fluctuations ◽  
Wall Pressure ◽  
Wave Number ◽  
Frequency Spectra ◽  
Wall Pressure Fluctuations ◽  
Number Frequency

scholarly journals Momentum and buoyancy transfer in atmospheric turbulent boundary layer over wavy water surface – Part 2: Wind–wave spectra

2013 ◽  
Vol 20 (5) ◽  
pp. 841-856 ◽  
Author(s):  
Yu. I. Troitskaya ◽  
E. V. Ezhova ◽  
D. A. Sergeev ◽  
A. A. Kandaurov ◽  
G. A. Baidakov ◽  
...  
Keyword(s):  
High Frequency ◽  
Wind Wave ◽  
Wave Number ◽  
Transfer Coefficients ◽  
Experiment Data ◽  
Mean Velocity ◽  
Tropical Ocean ◽  
Frequency Spectra ◽  
Number Frequency ◽  
Wave Induced

Abstract. Drag and mass exchange coefficients are calculated within a self-consistent problem for the wave-induced air perturbations and mean velocity and density fields using a quasi-linear model based on the Reynolds equations with down-gradient turbulence closure. This second part of the report is devoted to specification of the model elements: turbulent transfer coefficients and wave number-frequency spectra. It is shown that the theory agrees with laboratory and field experimental data well when turbulent mass and momentum transfer coefficients do not depend on the wave parameters. Among several model spectra better agreement of the theoretically calculated drag coefficients with TOGA (Tropical Ocean Global Atmosphere) COARE (Coupled Ocean–Atmosphere Response Experiment) data is achieved for the Hwang spectrum (Hwang, 2005) with the high frequency part completed by the Romeiser spectrum (Romeiser et al., 1997).

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