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Related papers: Disk wakes in nonlinear stratification

200 papers

A statistical mechanics theory for a fluid stratified in density is presented. The predicted statistical equilibrium state is the most probable outcome of turbulent stirring. The slow temporal evolution of the vertical density profile is…

Fluid Dynamics · Physics 2014-09-23 Antoine Venaille , Louis Gostiaux , Joël Sommeria

Wind turbine's wake, being convectively unstable, may behave as an amplifier of upstream perturbations and make the downstream turbine experience strong inflow fluctuations. In this work, we investigate the effects of the side-to-side…

Fluid Dynamics · Physics 2022-02-02 Zhaobin Li , Guodan Dong , Xiaolei Yang

The interaction between turbulent axisymmetric wakes plays an important role in many industrial applications, notably in the modelling of wind farms. While the non-equilibrium high Reynolds number scalings present in the wake of…

Fluid Dynamics · Physics 2021-03-29 M. Obligado , S. Klein , J. C. Vassilicos

We investigate fluid motions near the midplane of vertically stratified accretion disks with highly resistive midplanes. In such disks, the magnetorotational instability drives turbulence in thin layers surrounding a resistive, stable dead…

Earth and Planetary Astrophysics · Physics 2014-11-20 Jeffrey S. Oishi , Mordecai-Mark Mac Low

A large eddy simulation (LES) study of the flow around a 1/4 scale squareback Ahmed body at $Re_H=33,333$ is presented. The study consists of both wall-resolved (WRLES) and wall-modelled (WMLES) simulations, and investigates the bimodal…

Fluid Dynamics · Physics 2021-03-26 F. Hesse , A. S. Morgans

We investigate the nonlinear effects of uniform rotation on the Parker instability in an exponentially-stratified disk through high-resolution simulations. During the linear stage, the speed of gas motion is subsonic and the evolution with…

Astrophysics · Physics 2007-05-23 Jongsoo Kim , Dongsu Ryu , T. W. Jones

Internal waves, or waves that propagate within a stratified fluid, may break and cause mixing. While each individual mixing event may be small, collectively, internal wave breaking drive processes in the ocean that are critical to…

We analyze theoretically and experimentally the wake behind a horizontal cylinder of diameter $d$ horizontally translated at constant velocity $U$ in a fluid rotating about the vertical axis at a rate $\Omega$. Using particle image…

Particles suspended in turbulent flows are affected by the turbulence and at the same time act back on the flow. The resulting coupling can give rise to rich variability in their dynamics. Here we report experimental results from an…

Fluid Dynamics · Physics 2015-10-28 Varghese Mathai , Vivek N. Prakash , Jon Brons , Chao Sun , Detlef Lohse

The present work focuses on a specific bouncing behaviour as a particle settling through a three-layer stratified fluid in the absence of neutral buoyant position, which was firstly discovered by Abaid, N., Adalsteinsson D., Agyapong A. &…

Fluid Dynamics · Physics 2024-11-20 Shuhong Wang , Prabal Kandel , Jian Deng , C. P. Caulfield , Stuart B. Dalziel

An object's wake in a plasma with small Debye length that drifts \emph{across} the magnetic field is subject to electrostatic electron instabilities. Such situations include, for example, the moon in the solar wind wake and probes in…

Plasma Physics · Physics 2015-03-27 I. H. Hutchinson , C. B. Haakonsen , C. Zhou

Large eddy simulations and three-dimensional proper orthogonal decomposition were used to study the interaction between a large stationary and moving bluff body and a high Reynolds number stably-stratified turbulent boundary layer. An…

Fluid Dynamics · Physics 2019-01-23 John S. Haywood , Adrian Sescu

A large eddy simulation (LES) with an extended Smagorinsky model has been carried to investigate numerically the fully developed turbulent flow of a shear thinning fluid (n=0.75) in a stationary pipe at a simulation's Reynolds number equals…

Fluid Dynamics · Physics 2020-06-01 Mohamed Abdi , Meryem Ould-Rouiss , Abdelkader Noureddine

A linear stability analysis of a multi-component and magnetized Galactic disk model is presented. The disk model uses the observed stratifications for the gas density and gravitational acceleration at the solar neighborhood and, in this…

Astrophysics · Physics 2009-10-31 Jongsoo Kim , Jose Franco , S. S. Hong , Alfredo Santillan , Marco A. Martos

Accurate prediction of wake dynamics behind hydrofoils is critical for mitigating vortex-induced vibrations and improving the performance of hydraulic machinery. Conventional turbulence modeling approaches often struggle to capture the…

Fluid Dynamics · Physics 2026-01-30 Gabriele Gaiti , Chirag Trivedi , Kristian F. Sagmo

Dynamics of linear perturbations in a differentially rotating accretion disk with non-homogeneous vertical structure is investigated. It has been found that turbulent viscosity results in instability of both pinching oscillations, and…

Astrophysics · Physics 2007-05-23 A. V. Khoperskov , S. S. Khrapov

An array of spheres descending slowly through a viscous fluid always clumps [J.M. Crowley, J. Fluid Mech. {\bf 45}, 151 (1971)]. We show that anisotropic particle shape qualitatively transforms this iconic instability of collective…

Soft Condensed Matter · Physics 2020-10-28 Rahul Chajwa , Narayanan Menon , Sriram Ramaswamy , Rama Govindarajan

We demonstrate that in N-body simulations of isolated disc galaxies there is numerical vertical heating which slowly increases the vertical velocity dispersion and the disc thickness. Even for models with over a million particles in a disc,…

Cosmology and Nongalactic Astrophysics · Physics 2015-06-16 S. A. Rodionov , N. Ya. Sotnikova

In this paper, using multiple scale analysis we derive a generalized mathematical model for amplitude evolution, and for calculating the energy exchange in resonant and near-resonant global triads consisting of weakly nonlinear internal…

Fluid Dynamics · Physics 2020-05-27 G. Saranraj , Anirban Guha

The Rossby wave instability (RWI) is the fundamental non-axisymmetric radial shear instability in disks. The RWI can facilitate disk accretion, set the shape of planetary gaps and produce large vortices. It arises from density and/or…

Earth and Planetary Astrophysics · Physics 2024-07-18 Eonho Chang , Andrew N. Youdin