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Related papers: Low magnetic Prandtl number dynamos with helical f…

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High-fidelity simulations are performed to study active flow control techniques for alleviating deep dynamic stall of a SD7003 airfoil in plunging motion. The flow Reynolds number is $Re=60{,}000$ and the freestream Mach number is $M=0.1$.…

This paper examines the behavior of the dimensionless dissipation rate $C_{\varepsilon}$ for stationary and nonstationary magnetohydrodynamic (MHD) turbulence in presence of external forces. By combining with previous studies for freely…

Fluid Dynamics · Physics 2017-01-05 Moritz Linkmann , Arjun Berera , Erin E. Goldstraw

The problem of the dynamo effect for a Kraichnan incompressible helicity-free velocity field is considered. Exploiting a quantum formalism first introduced by Kazantsev (A.P. Kazantsev, Sov. Phys. JETP 26, 1031-1034 (1968)), we show that a…

Fluid Dynamics · Physics 2007-05-23 D. Vincenzi

We present a high-order numerical study of the dependence of the dynamo onset on different electromagnetic boundary conditions, in convecting Boussinesq flows forced by a temperature gradient. Perfectly conducting boundaries, vacuum, and…

Fluid Dynamics · Physics 2023-03-21 Mauro Fontana , Pablo D. Mininni , Pablo Dmitruk

The linear marginal instability of an axisymmetric MHD Taylor-Couette flow of infinite vertical extension is considered. For flows with a resting outer cylinder there is a well-known characteristic Reynolds number even without magnetic…

Astrophysics · Physics 2016-08-16 G. Rüdiger , D. A. Shalybkov

We study the flow response to an externally imposed homogeneous magnetic field in a turbulent swirling flow of liquid sodium -- the VKS2 experiment in which magnetic Reynolds numbers Rm up to 50 are reached. Induction effects are larger…

We perform fully kinetic simulations of flows known to produce dynamo in magnetohydrodynamics (MHD), considering scenarios with low Reynolds number and high magnetic Prandtl number, relevant for galaxy cluster scale fluctuation dynamos. We…

A large set of numerical simulations of magnetohydrodynamic (MHD) turbulence induced by the magnetorotational instability (MRI) is presented. Revisiting the previous survey conducted by Sano et al. (2004), we investigate the gas pressure…

Solar and Stellar Astrophysics · Physics 2015-08-06 Takashi Minoshima , Shigenobu Hirose , Takayoshi Sano

We investigate how the strength of the Lorentz force alters stellar convection zone dynamics in a suite of buoyancy-dominated, three-dimensional, spherical shell convective dynamo models. This is done by varying only the magnetic Prandtl…

Solar and Stellar Astrophysics · Physics 2025-08-28 Krista M. Soderlund , Paula Wulff , Petri Käpylä , Jonathan M. Aurnou

Using a large number of numerical simulations we examine the steady state of rotating turbulent flows in triple periodic domains, varying the Rossby number $Ro$ (that measures the inverse rotation rate) and the Reynolds number $Re$ (that…

Fluid Dynamics · Physics 2018-03-14 Kannabiran Seshasayanan , Alexandros Alexakis

The existence of a dynamo effect in a simplified magnetohydrodynamic model of turbulence is considered when the magnetic Prandtl number approaches zero or infinity. The magnetic field is interacting with an incompressible…

Chaotic Dynamics · Physics 2009-11-11 Heikki Arponen , Peter Horvai

We study the dynamics of a dilute solution of rigid rodlike polymers in a viscous fluid at low Reynolds number by means of numerical simulations of a simple rheological model. We show that the rotational dynamics of polymers destabilizes…

Fluid Dynamics · Physics 2022-11-11 Leonardo Puggioni , Guido Boffetta , Stefano Musacchio

The linear marginal instability of an axisymmetric MHD Taylor-Couette flow of infinite vertical extension is considered. The dependence of the flow stability on magnetic Prandtl number, Pm, and gap-width between rotating cylinders is…

Astrophysics · Physics 2009-11-07 G. Ruediger , D. Shalybkov

A numerical study of convection with stress-free boundary conditions in the presence of an imposed magnetic field that is tilted with respect to the direction of gravity is carried out in the limit of small magnetic Reynolds number. The…

Fluid Dynamics · Physics 2021-11-03 Justin A. Nicoski , Ming Yan , Michael A. Calkins

For a three dimensional magnetohydrodynamic (MHD) plasma the dynamo action with ABC flow as initial condition has been studied. The study delineates crucial parameter that gives a transition from coherent nonlinear oscillation to dynamo.…

Plasma Physics · Physics 2019-01-29 Rupak Mukherjee , Rajaraman Ganesh

We investigate numerically the kinematic dynamo induced by the superposition of two helical waves in a periodic box as a simplified model to understand the dynamo action in astronomical bodies. The effects of magnetic Reynolds number,…

Fluid Dynamics · Physics 2015-06-03 Xing Wei

The effects of large scale mechanical forcing on the dynamics of rotating turbulent flows are studied by means of numerical simulations, varying systematically the nature of the mechanical force in time. We demonstrate that the…

Fluid Dynamics · Physics 2016-06-29 Vassilios Dallas , Steve Tobias

We show a method, for direct numerical simulations, to trigger and maintain turbulent bands directly at low Reynolds numbers in channel flow. The key is to impose a moving localised force which induces a local flow with sufficiently strong…

Fluid Dynamics · Physics 2020-10-28 Baofang Song , Xiangkai Xiao

This paper investigates the Reynolds number dependence of a turbulent mixing layer evolving from the Richtmyer-Meshkov instability using a series of direct numerical simulations of a well-defined narrowband initial condition for a range of…

Fluid Dynamics · Physics 2023-04-27 Michael Groom , Ben Thornber

Compositional convection is thought to be an important energy source for magnetic field generation within planetary interiors. The Prandtl number, $Pr$, characterizing compositional convection is significantly larger than unity, suggesting…

Geophysics · Physics 2017-04-05 Michael A. Calkins , Keith Julien , Steven M. Tobias