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Related papers: Turbulence in simulated HII regions

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We use continuous wavelet transform techniques to construct the global and environment-dependent wavelet statistics, such as energy spectrum and kurtosis, to study the fluctuation and intermittency of the turbulent motion in the cosmic…

Cosmology and Nongalactic Astrophysics · Physics 2024-10-10 Yun Wang , Ping He

We present two-dimensional fully-kinetic Particle-in-Cell simulations of decaying electromagnetic fluctuations. The computational box is such that wavelengths ranging from electron to ion gyroradii are resolved. The parameters used are…

Space Physics · Physics 2011-03-14 Enrico Camporeale , David Burgess

Dynamic fluctuations in the local density of non-identified hadron tracks reconstructed in the STAR TPC are studied using the discrete wavelet transform power spectrum technique which involves mixed event reference sample comparison. The…

Nuclear Experiment · Physics 2012-08-27 STAR Collaboration

The evolution of scalar fields transported by turbulent flow is characterized by the presence of fronts, which rule the small-scale statistics of scalar fluctuations. With the aid of numerical simulations, it is shown that: isotropy is not…

Chaotic Dynamics · Physics 2009-10-31 A. Celani , A. Lanotte , A. Mazzino , M. Vergassola

We present a method that can be used to recover the spectrum of turbulence from observations of optically thin emission lines formed in astrophysical disks. Within this method we analyze how line intensity fluctuations depend on the angular…

Instrumentation and Methods for Astrophysics · Physics 2016-03-23 D. V. Bisikalo , E. P. Kurbatov , Ya. N. Pavlyuchenkov , A. G. Zhilkin , P. V. Kaygorodov

This study investigates the impact of molecular thermal fluctuations on compressible decaying isotropic turbulence using the unified stochastic particle (USP) method, encompassing both two-dimensional (2D) and three-dimensional (3D)…

Fluid Dynamics · Physics 2023-07-03 Qihan Ma , Chunxin Yang , Song Chen , Kaikai Feng , Ziqi Cui , Jun Zhang

Current understanding of the kinetic-scale turbulence in weakly-collisional plasmas still remains elusive. We employ a general framework in which the turbulent energy transfer is envisioned as a scale-to-scale Langevin process. Fluctuations…

The multivariate tool of Principal Component Analysis (PCA) is applied to 23 fields in the FCRAO CO Survey of the Outer Galaxy. PCA enables the identification of line profile differences which are assumed to be generated from fluctuations…

Astrophysics · Physics 2009-11-07 Christopher M. Brunt , Mark H. Heyer

A novel investigation of the nature of intermittency in incompressible, homogeneous and isotropic turbulence is performed by a numerical study of the Navier-Stokes equations constrained on a fractal Fourier set. The robustness of the energy…

By using new results from direct simulations of turbulent channels at moderate friction Reynolds numbers (Retau <= 1900) and in very large numerical boxes, we examine the corrections to the similarity assumptions in the overlap and outer…

Fluid Dynamics · Physics 2013-09-12 Juan C. del Alamo , Javier Jimenez , Paulo Zandonade , Robert D. Moser

Recent experimental observations have demonstrated interesting instability phenomenon during thermal drawing of microstructured glass/polymer fibers, and these observations motivate us to examine surface-tension-driven instabilities in…

Fluid Dynamics · Physics 2011-08-12 D. S. Deng , J. -C. Nave , X. Liang , S. G. Johnson , Y. Fink

The Rayleigh-Plateau instability occurs when surface tension makes a fluid column become unstable to small perturbations. At nanometer scales, thermal fluctuations are comparable to surface energy densities. Consequently, at these scales,…

Fluid Dynamics · Physics 2023-06-21 Bryn Barker , John B. Bell , Alejandro L. Garcia

This work explores the potential of an information-theoretical causality detection method for unraveling the relation between fluctuating variables in complex nonlinear systems. The method is tested on some simple though nonlinear models,…

Plasma Physics · Physics 2014-08-12 B. Ph. van Milligen , G. Birkenmeier , M. Ramisch , T. Estrada , C. Hidalgo , A. Alonso

Context. Future X-ray observatories with high spectral resolution and imaging capabilities will enable measurements and mappings of emission line shifts in the intracluster medium (ICM). Such direct measurements can serve as unique probes…

Cosmology and Nongalactic Astrophysics · Physics 2024-03-19 Sophie Beaumont , Alexeï Molin , Nicolas Clerc , Étienne Pointecouteau , Mélina Vanel , Edoardo Cucchetti , Philippe Peille , François Pajot

On the basis of the lattice Boltzmann method we have done a numerical experiment of a forced turbulence in real space and time. Our new findings are summarized into two points. First in the analysis of the mean-field behavior of the…

Statistical Mechanics · Physics 2007-05-23 W. Sakikawa , O. Narikiyo

To study subregions of a turbulence velocity field, a long record of velocity data of grid turbulence is divided into smaller segments. For each segment, we calculate statistics such as the mean rate of energy dissipation and the mean…

Fluid Dynamics · Physics 2009-11-13 H. Mouri , A. Hori , M. Takaoka

In incompressible and periodic statistically stationary turbulence, exchanges of turbulent energy across scales and space are characterised by very intense and intermittent spatio-temporal fluctuations around zero of the time-derivative…

Fluid Dynamics · Physics 2018-08-28 Tatsuya Yasuda , John Christos Vassilicos

The velocity field of intracluster gas in galaxy clusters contains key information on the virialization of infalling material, the dissipation of AGN energy into the surrounding medium, and the validity of the hydrostatic hypothesis. The…

Cosmology and Nongalactic Astrophysics · Physics 2026-01-14 D. Eckert , M. Markevitch , J. A. ZuHone , M. Regamey , I. Zhuravleva , Y. Ichinohe , N. Truong , N. Okabe , D. R. Wik

Dynamic fluctuations in the local density of non-identified hadron tracks reconstructed in the STAR TPC are studied using the discrete wavelet transform power spectrum technique which involves mixed event reference sample comparison. The…

Nuclear Experiment · Physics 2017-08-23 Mikhail L. Kopytine

We consider the influence of mode - mode coupling in the inflaton field on the spectrum of primordial fluctuations. To this end, we formulate a phenomenological model where the inflaton fluctuations are treated as a fluid undergoing…

Astrophysics · Physics 2008-02-03 Esteban Calzetta , Mariana Grana