scholarly journals Inversion formula of multifractal energy dissipation in three-dimensional fully developed turbulence

2006 ◽  
Vol 73 (5) ◽  
Author(s):  
Jian-Liang Xu ◽  
Wei-Xing Zhou ◽  
Hai-Feng Liu ◽  
Xin Gong ◽  
Fu-Cheng Wang ◽  
...  
2003 ◽  
Vol 14 (04) ◽  
pp. 459-470 ◽  
Author(s):  
WEI-XING ZHOU ◽  
DIDIER SORNETTE ◽  
VLADILEN PISARENKO

We extend the analysis of Ref. 16 showing statistically significant log-periodic corrections to scaling in the moments of the energy dissipation rate in experiments at high Reynolds number (≈ 2500) of three-dimensional fully developed turbulence. First, we develop a simple variant of the canonical averaging method using a rephasing scheme between different samples based on pairwise correlations that confirms Zhou and Sornette's previous results. The second analysis uses a simpler local spectral approach and then performs averages over many local spectra. This yields stronger evidence of the existence of underlying log-periodic undulations, with the detection of more than 20 harmonics of a fundamental logarithmic frequency f = 1.434 ± 0.007 corresponding to the preferred scaling ratio γ = 2.008 ± 0.006.


Fractals ◽  
2002 ◽  
Vol 10 (03) ◽  
pp. 321-327 ◽  
Author(s):  
M. GREINER ◽  
B. JOUAULT

In standard experiments, time series of fully developed turbulent fields are recorded in one point, which according to the frozen flow hypothesis can be interpreted as an instantaneous one-dimensional spatial section through a three-dimensional field. This observational reduction in dimensions is absolutely necessary to be taken into account for the explanation of observed multiplier correlations in the energy dissipation field. We demonstrate this for discrete and continuous multiplicative cascade processes, which are empirically known to describe the multifractal energy flux from integral to dissipation scales.


2005 ◽  
Vol 17 (2) ◽  
pp. 021701 ◽  
Author(s):  
L. Biferale ◽  
G. Boffetta ◽  
A. Celani ◽  
A. Lanotte ◽  
F. Toschi

1995 ◽  
Vol 74 (11) ◽  
pp. 1986-1989 ◽  
Author(s):  
G. Chavarria ◽  
C. Baudet ◽  
S. Ciliberto

2001 ◽  
Vol 295 (1-2) ◽  
pp. 250-253 ◽  
Author(s):  
Fernando M. Ramos ◽  
Reinaldo R. Rosa ◽  
Camilo Rodrigues Neto ◽  
Mauricio J.A. Bolzan ◽  
Leonardo D.Abreu Sá ◽  
...  

2018 ◽  
Vol 2018 ◽  
pp. 1-14 ◽  
Author(s):  
Aoshuang Ding ◽  
Xiaodong Ren ◽  
Xuesong Li ◽  
Chunwei Gu

With rotating machineries working at high speeds, oil flow in bearings becomes superlaminar. Under superlaminar conditions, flow exhibits between laminar and fully developed turbulence. In this study, superlaminar oil flow in an oil-lubricated tilting-pad journal bearing is analyzed through computational fluid dynamics (CFD). A three-dimensional bearing model is established. CFD results from the laminar model and 14 turbulence models are compared with experimental findings. The laminar simulation results of pad-side pressure are inconsistent with the experimental data. Thus, the turbulence effects on superlaminar flow should be considered. The simulated temperature and pressure distributions from the classical fully developed turbulence models cannot correctly fit the experimental data. As such, turbulence models should be corrected for superlaminar flow. However, several corrections, such as transition correction, are unsuitable. Among all the flow models, the SST model with low-Re correction exhibits the best pressure distribution and turbulence viscosity ratio. Velocity profile analysis confirms that a buffer layer plays an important role in the superlaminar boundary layer. Classical fully developed turbulence models cannot accurately predict the buffer layer, but this problem can be resolved by initiating an appropriate low-Re correction. Therefore, the SST model with low-Re correction yields suitable results for superlaminar flows in bearings.


1996 ◽  
Vol 6 (4) ◽  
pp. 573-583 ◽  
Author(s):  
F. Belin ◽  
J. Maurer ◽  
P. Tabeling ◽  
H. Willaime

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