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Related papers: Generalised actuator disk theory: wake development…

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We carry out three-dimensional, high resolution (up to $1024^2\times 256$) hydrodynamic simulations of the evolution of vortices in vertically unstratified Keplerian disks using the shearing sheet approximation. The transient amplification…

Astrophysics · Physics 2011-02-11 Yue Shen , James M. Stone , Thomas A. Gardiner , ;

This study investigates how variations in freestream turbulence (FST) and the thrust coefficient ($C_T$) influence wind turbine wakes. Wakes generated at $C_T \in \{0.5, 0.7,0.9\}$ are exposed to turbulent inflows with varying FST intensity…

Fluid Dynamics · Physics 2025-03-31 Martin Bourhis , Thomas Messmer , Michael Hölling , Oliver R. H. Buxton

We apply the proper orthogonal decomposition (POD) to large eddy simulation data of a wind turbine wake in a turbulent atmospheric boundary layer. The turbine is modeled as an actuator disk. Our analyis mainly focuses on the question…

Fluid Dynamics · Physics 2015-03-11 David Bastine , Björn Witha , Matthias Wächter , Joachim Peinke

This work builds on and confirms the theoretical findings of Part 1 of this paper, Moarref & Jovanovi\'c (2010). We use direct numerical simulations of the Navier-Stokes equations to assess the efficacy of blowing and suction in the form of…

Fluid Dynamics · Physics 2011-11-29 Binh K. Lieu , Rashad Moarref , Mihailo R. Jovanović

The majority of coastal flows are characterized by turbulence, rendering the application of shallow water equations an inadequate approach for their accurate description. This paper presents a theory for characterizing accelerated coastal…

Fluid Dynamics · Physics 2024-09-19 Arno Roland Ndengna Ngatcha

Spatially developing round jet flows are fundamental to numerous engineering applications. This letter applies the wave-particle turbulence simulation (WPTS) method, a recently developed multiscale approach, to simulate a spatially…

Fluid Dynamics · Physics 2025-07-22 Xiaojian Yang , Kun Xu

Turbulent viscosity in cold accretion disks is likely to be hydrodynamic in origin. We investigate the growth of hydrodynamic perturbations in a small region of a disk, which we model as a linear shear flow with Coriolis force, between two…

Astrophysics · Physics 2007-05-23 Banibrata Mukhopadhyay , Niayesh Afshordi , Ramesh Narayan

This study aims to examine the spatial evolution of the geometrical features of the turbulent/turbulent interface (TTI) in a cylinder wake. The wake is exposed to various turbulent backgrounds in which the turbulence intensity and the…

Fluid Dynamics · Physics 2023-09-11 Jiangang Chen , Oliver R. H. Buxton

Rotating turbulence is ubiquitous in nature. Previous works suggest that such turbulence could be described as an ensemble of interacting inertial waves across a wide range of length scales. For turbulence in macroscopic quantum…

This is the first of a series of papers aimed at developing and interpreting simulations of protoplanets interacting with turbulent accretion discs. Here we study the disc models prior to the introduction of a protoplanet.We study models in…

Astrophysics · Physics 2009-11-07 John C. B. Papaloizou , Richard P. Nelson

The formation and evolution of a wide class of astrophysical objects is governed by turbulent, magnetized accretion disks. Understanding their secular dynamics is of primary importance. Apart from enabling mass accretion via the transport…

High Energy Astrophysical Phenomena · Physics 2015-09-16 Oliver Gressel , Martin E. Pessah

Rotors operating in confined flows, or blockage, are commonly encountered in wind and water tunnels, as well as in shallow or dense deployments of hydrokinetic turbines. Confinement induces a streamwise pressure gradient in the channel,…

Fluid Dynamics · Physics 2026-03-10 I. M. L. Upfal , K. J. McClure , K. S. Heck , S. Pieris , J. W. Kurelek , M. Hultmark , M. F. Howland

We present angular momentum transport (torque) measurements in two recent experimental studies of the turbulent flow between independently rotating cylinders. In addition to these studies, we reanalyze prior torque measurements to expand…

Fluid Dynamics · Physics 2012-11-12 M. S. Paoletti , Dennis P. M. van Gils , B. Dubrulle , Chao Sun , Detlef Lohse , D. P. Lathrop

The observed Ekman spirals in the ocean are always "flatter" than that predicted by the classic theory. We propose that the universal flattening of Ekman spiral is mainly due to the damping associated with turbulent dissipation. Analytical…

Atmospheric and Oceanic Physics · Physics 2025-05-06 Jiacheng Wu , Yonggang Liu , Rui Xin Huang , Jinhan Xie , Zhaoying Wang , Shaoqing Zhang

Turn-taking behaviour is simulated in a coupled agents system. Each agent is modelled as a mobile robot with two wheels. A recurrent neural network is used to produce the motor outputs and to hold the internal dynamics. Agents are developed…

Adaptation and Self-Organizing Systems · Physics 2007-05-23 Hiroyuki Iizuka , Takashi Ikegami

We report new global ideal MHD simulations for thin accretion disks (with thermal scale height H/R=0.1 and 0.05) threaded by net vertical magnetic fields. Our computations span three orders of magnitude in radius, extend all the way to the…

Earth and Planetary Astrophysics · Physics 2018-04-25 Zhaohuan Zhu , James M. Stone

Turbulence-resolving simulations of wind turbine wakes are presented using a high--order flow solver combined with both a standard and a novel dynamic implicit spectral vanishing viscosity (iSVV and dynamic iSVV) model to account for…

Fluid Dynamics · Physics 2018-12-07 Georgios Deskos , Sylvain Laizet , Matthew D. Piggott

Understanding the mechanism that drives accretion has been the primary challenge in accretion disk theory. Turbulence provides a natural means of dissipation and the removal of angular momentum, but firmly establishing its presence in disks…

Astrophysics · Physics 2009-09-29 Bryan Mark Johnson

The volatile transition from quiescent laminar to strongly fluctuating turbulent dynamics in shear flows remains only poorly understood despite its practical importance and more than a century of intense research. The theoretical…

Fluid Dynamics · Physics 2016-09-08 Alberto de Lozar , Bjoern Hof

The origin of large scale magnetic fields in astrophysical rotators, and the conversion of gravitational energy into radiation near stars and compact objects via accretion have been subjects of active research for a half century.…

High Energy Astrophysical Phenomena · Physics 2015-05-14 Eric G. Blackman