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Related papers: Turbulence in simulated HII regions

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We study, by means of adaptive mesh refinement hydro- and magnetohydrodynamical simulations that cover a wide range of scales (from kpc to sub-parsec), the dimension of the most dissipative structures and the injection scale of the…

Astrophysics · Physics 2009-11-13 Miguel A. de Avillez , Dieter Breitschwerdt

We develop a framework for efficient streaming reconstructions of turbulent velocity fluctuations from limited sensor measurements with the goal of enabling real-time applications. The reconstruction process is simplified by computing…

Fluid Dynamics · Physics 2023-06-29 Rahul Arun , H. Jane Bae , Beverley J. McKeon

We study theoretically and numerically a family of multi-point dynamic susceptibilities that quantify the strength and characteristic lengthscales of dynamic heterogeneities in glass-forming materials. We use general theoretical arguments…

The velocity fluctuations for point vortex models are studied for the {\alpha}-turbulence equations, which are characterized by a fractional Laplacian relation between active scalar and the streamfunction. In particular, we focus on the…

Fluid Dynamics · Physics 2019-09-11 Giovanni Conti , Gualtiero Badin

Interstellar turbulence shapes the HI distribution in the Milky Way (MW). How this affects large-scale statistical properties of HI column density across the MW remains largely unconstrained. We use approx 13,000 square-degree GALFA-HI…

Astrophysics of Galaxies · Physics 2023-10-24 Amit K. Mittal , Brian L Babler , Snezana Stanimirovic , Nickolas Pingel

In this paper we numerically investigate the influence of dissipation during particle collisions in an homogeneous turbulent velocity field by coupling a discrete element method to a Lattice-Boltzmann simulation with spectral forcing. We…

Fluid Dynamics · Physics 2012-12-18 Thomas Burgener , Dirk Kadau , Hans Jürgen Herrmann

Time scales of turbulent strain activity, denoted as the strain persistence times of first and second order, are obtained from time-dependent expectation values and correlation functions of lagrangian rate-of-strain eigenvalues taken in…

Fluid Dynamics · Physics 2014-01-06 L. Moriconi , R. M. Pereira

For several flows of laboratory turbulence, we obtain long records of velocity data. These records are divided into numerous segments. In each segment, we calculate the mean rate of energy dissipation, the mean energy at each scale, and the…

Fluid Dynamics · Physics 2015-05-13 H. Mouri , A. Hori , M. Takaoka

New aspects of turbulence are uncovered if one considers flow motion from the perspective of a fluid particle (known as the Lagrangian approach) rather than in terms of a velocity field (the Eulerian viewpoint). Using a new experimental…

Fluid Dynamics · Physics 2009-11-07 N. Mordant , J. Delour , E. Leveque , A. Arneodo , J. -F. Pinton

In this study, eXplainable Artificial Intelligence (XAI) methods are applied to analyze flow fields obtained through PIV measurements of an axisymmetric turbulent jet. A convolutional neural network (U-Net) was trained to predict velocity…

Fluid Dynamics · Physics 2025-03-05 Enrico Amico , Lorenzo Matteucci , Gioacchino Cafiero

The gas motions in the intracluster medium (ICM) are governed by stratified turbulence. Stratified turbulence is fundamentally different from Kolmogorov (isotropic, homogeneous) turbulence; kinetic energy not only cascades from large to…

Astrophysics of Galaxies · Physics 2020-03-26 Rajsekhar Mohapatra , Christoph Federrath , Prateek Sharma

This paper introduces the Hidden Valley simulations, a set of trillion-particle N-body simulations in gigaparsec volumes aimed at intensity mapping science. We present details of the simulations and their convergence, then specialize to the…

Cosmology and Nongalactic Astrophysics · Physics 2019-11-19 Chirag Modi , Emanuele Castorina , Yu Feng , Martin White

Intermittency is one of central obstacles for understanding small-scale dynamics in the fully developed hydrodynamic turbulence. The modern approach is largely based on the multifractal theory of Parisi and Frisch which is, however,…

Fluid Dynamics · Physics 2023-05-12 Alexei A. Mailybaev

It has long been conjectured that, in three dimensional turbulence, velocity modes at scales larger than the forcing scale follow equilibrium dynamics. Recent numerical and experimental evidence show that such modes share the same mean…

Fluid Dynamics · Physics 2023-11-27 Alexandros Alexakis , Sergio Chibbaro , Guillaume Michel

We report experiments on the full space and time resolved statistics of capillary wave turbulence at the air-water interface. The three-dimensional shape of the free interface is measured as a function of time by using the optical method of…

Fluid Dynamics · Physics 2013-03-18 Michael Berhanu , Eric Falcon

Some techniques for the study of intermittency by means of wavelet transforms, are presented on an example of synthetic turbulent signal. Several features of the turbulent field, that cannot be probed looking at standard structure function…

chao-dyn · Physics 2007-05-23 Piero Olla , Paolo Paradisi

We study the global, i.e. radially averaged, high Reynolds number (asymptotic) scaling of streamwise turbulence intensity squared defined as ${I^2=\overline{u^2}/U^2}$, where $u$ and $U$ are the fluctuating and mean velocities, respectively…

Fluid Dynamics · Physics 2021-06-29 Nils T. Basse

The Ha peak intensity, velocity shift and velocity dispersion maps of the giant HII region NGC 604 in M 33, obtained by two dimensional high spatial resolution Fabry-Perot observations with TAURUS II at the 4.2 m William Herschel Telescope…

Astrophysics · Physics 2009-10-30 G. A. Medina Tanco , N. Sabalisck , V. Jatenco-Pereira , R. Opher

We perform rescaled range analysis upon the signals measured by Dual Particle Dynamical Analyzer in gas-liquid two-phase turbulent jets. A novel rescaled range analysis is proposed to investigate these unevenly sampled signals. The Hurst…

Fluid Dynamics · Physics 2012-10-08 Li-Jun Ji , Wei-Xing Zhou , Hai-feng Liu , Xin Gong , Fu-Chen Wang , Zun-Hong Yu

We review recent computer simulation studies of undulating lipid bilayers. Theoretical interpretations of such fluctuating membranes are most commonly based on generalized Helfrich-type elastic models, with additional contributions of local…

Biological Physics · Physics 2013-09-03 Friederike Schmid