English
Related papers

Related papers: Zonal shear and super-rotation in a magnetized sph…

200 papers

We report experimental measurements of the flow in a cubic container submitted to a longitudinal libration, i.e. a rotation modulated in time. Velocity fields in a vertical and a horizontal plane are measured in the librating frame using a…

Fluid Dynamics · Physics 2013-10-15 J. Boisson , C. Lamriben , L. R. M. Maas , P. -P. Cortet , F. Moisy

We study the magneto-rotational instability of an incompressible flow which rotates with angular velocity Omega(r)=a+b/r^2 where r is the radius and $a$ and b are constants. We find that an applied magnetic field destabilises the flow, in…

Astrophysics · Physics 2008-11-26 Ashley P. Willis , Carlo F. Barenghi

Jupiter and Saturn exhibit alternating east-west jet streams as seen from surface. The origin of these zonal flows has been debated for decades. The high-precision gravity measurements by Juno mission and the grand finale of Cassini mission…

Earth and Planetary Astrophysics · Physics 2024-08-06 Shanshan Xue , Yufeng Lin

We report a novel experimental technique that measures simultaneously in three dimensions the trajectories, the translation, and the rotation of finite size inertial particles together with the turbulent flow. The flow field is analyzed by…

Fluid Dynamics · Physics 2012-12-24 Simon Klein , Mathieu Gibert , Antoine Bérut , Eberhard Bodenschatz

Direct numerical simulations of turbulent non-rotating and rotating Plane Couette Flow with a periodically modulated plate velocity are conducted to study the effect of modulated forcing on turbulent shear flows. The time averaged shear…

Fluid Dynamics · Physics 2022-05-24 M. Wasy Akhtar , Rodolfo Ostilla Mónico

Numerical solutions of the incompressible magnetohydrodynamic (MHD) equations are reported for the interior of a rotating, perfectly-conducting, rigid spherical shell that is insulator-coated on the inside. A previously-reported spectral…

Fluid Dynamics · Physics 2009-11-13 P. D. Mininni , D. C. Montgomery , L. Turner

We theoretically and experimentally investigate the flow field that emerges from a rod-like microrotor rotating about its center in a non-axisymmetric manner. A simple theoretical model is proposed that uses a superposition of two rotlets…

Fluid Dynamics · Physics 2016-02-24 Jannis Köhler , Jan Friedrich , Andreas Ostendorf , Evgeny Gurevich

Direct numerical simulations of a liquid metal filling the gap between two concentric spheres are presented. The flow is governed by the interplay between the rotation of the inner sphere (measured by the Reynolds number Re) and a weak…

Fluid Dynamics · Physics 2023-07-26 Ferran Garcia , Martin Seilmayer , André Giesecke , Frank Stefani

We study rotating thermal convection in spherical shells. We base our analysis on a set of about 450 direct numerical simulations of the (magneto)hydrodynamic equations under the Boussinesq approximation. The Ekman number ranges from…

Earth and Planetary Astrophysics · Physics 2016-01-20 Rakesh K. Yadav , Thomas Gastine , Ulrich R. Christensen , Lucia Duarte , Ansgar Reiners

Motivated by recent studies in geophysical and planetary sciences, we investigate the PDE-analytical aspects of time-averages for barotropic, inviscid flows on a fast rotating sphere $S^2$. Of particular interests are the incompressible…

Analysis of PDEs · Mathematics 2011-08-15 Bin Cheng , Alex Mahalov

We perform direct numerical simulations of rapidly rotating annular centrifugal convection to investigate how mixed (asymmetric) velocity boundary conditions and geometric curvature shape the flow organisation and heat transfer. Motivated…

Fluid Dynamics · Physics 2026-01-30 Jun Zhong , Chao Sun

We reveal and investigate a new type of linear axisymmetric helical magnetorotational instability which is capable of destabilizing viscous and resistive rotational flows with radially increasing angular velocity, or positive shear. This…

Fluid Dynamics · Physics 2019-10-23 G. Mamatsashvili , F. Stefani , R. Hollerbach , G. Rüdiger

This paper numerically investigates the shear flow between double concentric spherical boundaries rotating differentially, so-called spherical Couette flow, under unstable thermal stratification, focusing on the boundary of the…

Fluid Dynamics · Physics 2021-11-30 Taishi Inagaki , Tomoaki Itano , Masako Sugihara-Seki

The onset of convection in the form of magneto-inertial waves in a rotating fluid sphere permeated by a constant axial electric current is studied through a perturbation analysis. Explicit expressions for the dependence of the Rayleigh…

Fluid Dynamics · Physics 2021-01-19 Radostin D. Simitev , Friedrich H. Busse

The spherical Couette system consists of two differentially rotating concentric spheres with a fluid filled in between. We study a regime where the outer sphere is rotating rapidly enough so that the Coriolis force is important and the…

Fluid Dynamics · Physics 2024-12-16 Ankit Barik , Santiago A. Triana , Michael Hoff , Johannes Wicht

We investigate the properties of forced inertial modes of a rotating fluid inside a spherical shell. Our forcing is tidal like, but its main property is that it is on the large scales. Our solutions first confirm some analytical results…

Solar and Stellar Astrophysics · Physics 2015-05-14 M. Rieutord , L. Valdettaro

In preparation for an experimental study of magnetorotational instability (MRI) in liquid metal, we present non-ideal two-dimensional magnetohydrodynamic simulations of the nonlinear evolution of MRI in the experimental geometry. The…

Astrophysics · Physics 2009-11-13 Wei Liu , Jeremy Goodman , Hantao Ji

We study both experimentally and numerically the steady zonal flow generated by longitudinal librations of a spherical rotating container. This study follows the recent weakly nonlinear analysis of Busse (2010), developed in the limit of…

Fluid Dynamics · Physics 2011-06-29 Alban Sauret , David Cébron , Cyprien Morize , Michael Le Bars

We numerically demonstrate the feasibility of kinematic fast dynamos for a class of time-periodic axisymmetric flows of conducting fluid confined inside a sphere. The novelty of our work is in considering the realistic flows, which are…

Plasma Physics · Physics 2013-09-19 I. V. Khalzov , C. M. Cooper , C. B. Forest

We analyze the main features of granular shear flow through experimental measurements in a Couette geometry and a comparison to a locally Newtonian, continuum model of granular flow. The model is based on earlier hydrodynamic models,…

Statistical Mechanics · Physics 2021-05-26 L. Bocquet , W. Losert , D. Schalk , T. C. Lubensky , J. P. Gollub