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Related papers: Generalizing the wavelet-based multifractal formal…

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We study the Lagrangian trajectories of statistically isotropic, homogeneous, and stationary divergence free spatiotemporal random vector fields. We design this advecting Eulerian velocity field such that it gets asymptotically rough and…

Fluid Dynamics · Physics 2020-07-08 Jason Reneuve , Laurent Chevillard

The phenomenology of velocity statistics in turbulent flows, up to now, relates to different models dealing with either signed or unsigned longitudinal velocity increments, with either inertial or dissipative fluctuations. In this paper, we…

Statistical Mechanics · Physics 2007-05-23 L. Chevillard , B. Castaing , E. Leveque , A. Arneodo

We report the first attempt to mode decomposition of the velocity field using wavelet transforms in the application to the magnetized turbulence analysis. We compare results of the separation with respect to the global and local mean…

Astrophysics · Physics 2007-05-23 Grzegorz Kowal , Alex Lazarian

We address the problem of studying interstellar turbulence using spectral line data. We find a criterion when the velocity centroids may provide trustworthy velocity statistics. To enhance the scope of centroids applications, we construct a…

Astrophysics · Physics 2009-11-07 A. Lazarian , A. Esquivel

Modal decomposition techniques are important tools for the analysis of unsteady flows and, in order to provide meaningful insights with respect to coherent structures and their characteristic frequencies, the modes must possess a robust…

Fluid Dynamics · Physics 2023-08-24 Lucas F. de Souza , Renato F. Miotto , William R. Wolf

High-resolution numerical simulations are utilized to examine isotropic turbulence in a compressible fluid when long wavelength velocity fluctuations approach light speed. Spectral analysis reveals an inertial sub-range of relativistic…

High Energy Astrophysical Phenomena · Physics 2013-01-04 Jonathan Zrake , Andrew MacFadyen

We propose an alternative formulation of structure functions for the velocity field in fully developed turbulence. Instead of averaging moments of the velocity differences as a function of the distance, we suggest to average moments of the…

chao-dyn · Physics 2009-10-31 Mogens H. Jensen

Fine scales of turbulent velocity fields, beyond the inertial range and well into the dissipative range, are highly intermittent. It has been hypothesized that complex plane singularities are the principal mechanism behind fine scale…

Fluid Dynamics · Physics 2015-11-03 Andre Souza , Divakar Viswanath

The recent development of the Velocity Gradient Technique allows observers to map magnetic field orientations and magnetization using the direction of velocity gradients. Aside from the directions, amplitudes of velocity gradients also…

Astrophysics of Galaxies · Physics 2020-05-15 Ka Ho Yuen , A. Lazarian

A phenomenological theory of the fluctuations of velocity occurring in a fully developed homogeneous and isotropic turbulent flow is presented. The focus is made on the fluctuations of the spatial (Eulerian) and temporal (Lagrangian)…

The probability distribution functions of the circulation of velocity in three-dimensional decaying isotropic turbulence are examined by the database of the numerical simulation based on the pseudospectral method. It is shown that the…

High Energy Physics - Theory · Physics 2009-10-22 Makoto Umeki

Every volumetric velocimetry measurements based on tracer (particles, bubbles, etc.) detection can be strongly influenced by the optical screening phenomenon. It has to be taken into account when the the statistical properties associated to…

Fluid Dynamics · Physics 2014-07-28 Tristan Cambonie , Jean-Luc Aider

We study the multifractal temporal scaling properties of river discharge and precipitation records. We compare the results for the multifractal detrended fluctuation analysis method with the results for the wavelet transform modulus maxima…

Vortex element methods are often used to efficiently simulate incompressible flows using Lagrangian techniques. Use of the FMM (Fast Multipole Method) allows considerable speed up of both velocity evaluation and vorticity evolution terms in…

Computational Physics · Physics 2015-06-03 Nail A. Gumerov , Ramani Duraiswami

We study Variational Rectified Flow Matching, a framework that enhances classic rectified flow matching by modeling multi-modal velocity vector-fields. At inference time, classic rectified flow matching 'moves' samples from a source…

Machine Learning · Computer Science 2025-02-14 Pengsheng Guo , Alexander G. Schwing

In this article, we construct two families of nonsymmetrical multifractal fields. One of these families is used for the modelization of the velocity field of turbulent flows.

Probability · Mathematics 2009-11-13 Raoul Robert , Vincent Vargas

In this paper we present applications of methods from wavelet analysis to polynomial approximations for a number of accelerator physics problems. According to variational approach in the general case we have the solution as a…

Accelerator Physics · Physics 2009-10-31 Antonina N. Fedorova , Michael G. Zeitlin , Zohreh Parsa

A multifractal analysis is performed on a three-dimensional grayscale image associated with a complex system. First, a procedure for generating 3D synthetic images (2D image stacks) of a complex structure exhibiting multifractal behaviour…

Statistical Mechanics · Physics 2013-10-11 Lorenzo Milazzo

The stationary velocity field (SVF) approach allows to build parametrizations of invertible deformation fields, which is often a desirable property in image registration. Its expressiveness is particularly attractive when used as a block…

Computer Vision and Pattern Recognition · Computer Science 2024-10-16 Johannes Bostelmann , Ole Gildemeister , Jan Lellmann

Turbulence is a complex phenomenon that has a chaotic nature with multiple spatio-temporal scales, making predictions of turbulent flows a challenging topic. Nowadays, an abundance of high-fidelity databases can be generated by experimental…

Fluid Dynamics · Physics 2022-08-12 Mustafa Z. Yousif , Linqi Yu , Sergio Hoyas , Ricardo Vinuesa , HeeChang Lim