English
Related papers

Related papers: Simulating turbulent mixing caused by local instab…

200 papers

Relatively strongly stratified turbulent flows tend to self-organise into a 'layered anisotropic stratified turbulence' (LAST) regime, characterised by relatively deep and well-mixed density 'layers' separated by relatively thin…

This paper continues the systematic investigation of diffusive shear instabilities initiated in Part I of this series. In this work, we primarily focus on quantifying the impact of non-local mixing, which is not taken into account in Zahn's…

Solar and Stellar Astrophysics · Physics 2018-07-25 D. Gagnier , P. Garaud

Most of the turbulent flows appearing in nature (e.g. geophysical and astrophysical flows) are subjected to strong rotation and stratification. These effects break the symmetries of classical, homogenous isotropic turbulence. In doing so,…

Fluid Dynamics · Physics 2015-09-11 Corentin Herbert , Annick Pouquet , Raffaele Marino

We perform two high resolution direct numerical simulations of stratified turbulence for Reynolds number equal to Re~25000 and Froude number respectively of Fr~0.1 and Fr~0.03. The flows are forced at large scale and discretized on an…

Fluid Dynamics · Physics 2014-12-04 C. Rorai , P. D. Mininni , A. Pouquet

We advance our prior energy- and flux-budget turbulence closure model (Zilitinkevich et al., 2007, 2008) for the stably stratified atmospheric flows and extend it accounting for additional vertical flux of momentum and additional…

Atmospheric and Oceanic Physics · Physics 2015-05-13 S. S. Zilitinkevich , T. Elperin , N. Kleeorin , V. L'vov , I. Rogachevskii

We present results of high-resolution numerical simulations of compressible 2D turbulence forced at intermediate spatial scales with a solenoidal white-in-time external acceleration. A case with an isothermal equation of state, low energy…

Astrophysics of Galaxies · Physics 2019-06-27 Alexei G. Kritsuk

The turbulent flow within and above a sparse canopy is investigated using direct numerical simulations. The balance of Reynolds to viscous stresses within the canopy is observed to be similar to that over a smooth wall. From this, a scaling…

Fluid Dynamics · Physics 2018-10-25 Akshath Sharma , Ricardo García-Mayoral

We develop an analytic framework to understand fragmentation in turbulent, self-gravitating media. Previously, we showed some properties of turbulence can be predicted with the excursion-set formalism. Here, we generalize to fully…

Cosmology and Nongalactic Astrophysics · Physics 2013-07-02 Philip F. Hopkins

Molecular dynamical (MD) simulations are performed to simulate two dimensional vibrofluidized granular materials in this work. Statistics on simulation results indicate that there exist shocks propagating upward in each vibrating cycle.…

Soft Condensed Matter · Physics 2007-05-23 Kai Huang , Guoqing Miao , Peng Zhang , Yifei Zhu , Rongjue Wei

We present full 2 Pi global 3-D stratified MHD simulations of accretion disks. We interpret our results in the context of proto-planetary disks. We investigate the turbulence driven by the magneto-rotational instability (MRI) using the…

Earth and Planetary Astrophysics · Physics 2015-05-27 M. Flock , N. Dzyurkevich , H. Klahr , N. J. Turner , Th. Henning

We present an experimental study of the mixing processes in a gravity current flowing on an inclined plane. The turbulent transport of momentum and density can be described in a very direct and compact form by a Prandtl mixing length model:…

Fluid Dynamics · Physics 2015-06-22 P. Odier , J. Chen , R. E. Ecke

Growing evidence is found in observations and numerical modelling of the importance of steep seafloor topography for turbulent diapycnal mixing leading to redistribution of suspended matter and nutrients, especially in waters with abundant…

Atmospheric and Oceanic Physics · Physics 2024-08-16 Hans van Haren

Small-scale effects of turbulent mixing are numerically investigated by applying the map-based, stochastic, one-dimensional turbulence (ODT) model to confined planar jets. The model validation is carried out for the momentum transport by…

Fluid Dynamics · Physics 2019-04-19 Marten Klein , Christian Zenker , Heiko Schmidt

This paper explores decaying turbulence beneath surface waves that is initially isotropic and shear-free. We start by presenting phenomenology revealed by wave-averaged numerical simulations: an accumulation of angular momentum in coherent…

Fluid Dynamics · Physics 2025-10-10 Gregory L. Wagner , Navid C. Constantinou

Direct numerical simulations are carried out to investigate scalar mixing in an isotropic turbulent flow with a time-periodic forcing. For high amplitudes of the modulation, it is shown that the average mixing rate is negatively affected at…

Fluid Dynamics · Physics 2016-04-12 Yuyao Yang , Robert Chahine , Robert Rubinstein , Wouter Bos

We report numerical simulations of surface gravity waves forced at small scale and the subsequent inverse cascade of wave action. We combine the spectral approach to simulating weakly nonlinear waves with the capabilities of modern Graphics…

Fluid Dynamics · Physics 2024-04-17 CHristopher Higgins , Basile Gallet

One of the pivotal questions in the dynamics of the oceans is related to the cascade of mechanical energy in the abyss and its contribution to mixing. Here, we propose internal wave attractors in the large amplitude regime as a unique…

Recent experimental and computational studies indicate that near wall turbulent flows can be characterized by universal small scale autonomous dynamics that are modulated by large scale structures. We formulate numerical simulations of near…

Fluid Dynamics · Physics 2021-01-21 Sean P. Carney , Björn Engquist , Robert D. Moser

It has often been proposed that the formation of large-scale motion (or bulges) is a consequence of successive mergers and/or growth of near-wall hairpin vortices. In the present study, we report our direct observation that large-scale…

Fluid Dynamics · Physics 2017-11-01 Matteo de Giovanetti , Hyung Jin Sung , Yongyun Hwang

Coupled mixed convective and stratified systems are common in natural flows. To study experimentally the associated dynamics, we use a singular property of water: its non-linear equation of state is characterised by a maximum density close…

Fluid Dynamics · Physics 2020-11-10 Pierre Léard , Benjamin Favier , Patrice Le Gal , Michael Le Bars