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Related papers: High-speed shear driven dynamos. Part 1. Asymptoti…

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The discontinuous shear thickening (DST) of dense suspensions is a remarkable phenomenon in which the viscosity can increase by several orders of magnitude at a critical shear rate. It has the appearance of a first order phase transition…

Soft Condensed Matter · Physics 2015-05-12 Romain Mari , Ryohei Seto , Jeffrey F. Morris , Morton M. Denn

In the approximation of linear dissipative magnetohydrodynamics (MHD) it can be shown that driven MHD waves in magnetic plasmas with high Reynolds number exhibit a near resonant behaviour if the frequency of the wave becomes equal to the…

Astrophysics · Physics 2010-06-18 C. T. M. Clack , I. Ballai , M. S. Ruderman

The evolution of magnetic fields is studied using simulations of forced helical turbulence with strong imposed shear. After some initial exponential growth, the magnetic field develops a large scale travelling wave pattern. The resulting…

Astrophysics · Physics 2009-10-31 Axel Brandenburg , Alberto Bigazzi , Kandaswamy Subramanian

The effect of precession in a rotating sphere filled with fluid was studied with direct numerical simulations, both in the incompressible hydrodynamics (HD) and magnetohydrodynamics (MHD) scenarios. In both cases the asymptotic state and…

Fluid Dynamics · Physics 2022-12-13 Manuel I. Etchevest , Mauro Fontana , Pablo Dmitruk

We analyze the spectral properties of driven, supersonic compressible magnetohydrodynamic (MHD) turbulence obtained via high-resolution numerical experiments, for application to understanding the dynamics of giant molecular clouds. Via…

Astrophysics · Physics 2009-11-07 Jason G. Vestuto , Eve C. Ostriker , James M. Stone

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

In the presence of magnetic helicity, inverse transfer from small to large scales is well known in magnetohydrodynamic (MHD) turbulence and has applications in astrophysics, cosmology, and fusion plasmas. Using high resolution direct…

Cosmology and Nongalactic Astrophysics · Physics 2015-02-23 Axel Brandenburg , Tina Kahniashvili , Alexander G. Tevzadze

Steady Low $R_m$ MHD turbulence is investigated here through estimates of upper bounds for attractor dimension. A flow between two parallel walls with an imposed perpendicular magnetic field is considered. The flow is defined by its maximum…

Fluid Dynamics · Physics 2020-06-09 Alban Pothérat , Thierry Alboussière

One of the most important predictions in magnetohydrodynamics (MHD) is that in the presence of a uniform magnetic field $\textbf{b}_{0}$ a transition from weak to strong wave turbulence should occur when going from large to small…

Fluid Dynamics · Physics 2016-03-23 Romain Meyrand , Sebastien Galtier , Khurom H. Kiyani

The 2D second-mode is a potent instability in hypersonic boundary layers (HBLs). We study its linear and nonlinear evolution, followed by its role in transition and eventual breakdown of the HBL into a fully turbulent state. Linear…

Fluid Dynamics · Physics 2020-12-02 S. Unnikrishnan , Datta V. Gaitonde

The first consistent model for the turbulent tachocline is presented, with the turbulent diffusivity computed within the model instead of being specified arbitrarily. For the origin of the 3D turbulence a new mechanism is proposed. Owing to…

Astrophysics · Physics 2015-06-24 K. Petrovay

We combine simulations with new analyses that overcome previous pitfalls to explicate how nonhelical mean-field dynamos grow and saturate in unstratified, magnetorotationally driven turbulence. Shear of the mean radial magnetic field…

Plasma Physics · Physics 2025-11-20 Tushar Mondal , Pallavi Bhat , Fatima Ebrahimi , Eric G. Blackman

Magnetic fields are widely observed in the Universe in virtually all astrophysical objects, from individual stars to entire galaxies, even in the intergalactic medium, but their specific generation has long been debated. Due to the…

Astrophysics of Galaxies · Physics 2017-11-08 Michael Rieder , Romain Teyssier

This paper investigates the non-linear dynamics of horizontal shear instability in an incompressible, stratified and rotating fluid in the non-traditional $f$-plane, i.e. with the full Coriolis acceleration, using direct numerical…

Fluid Dynamics · Physics 2025-10-22 Camille Moisset , Paul Billant , Junho Park , Stéphane Mathis

We unite the one-flow-dominated-state (OFDS) argument of \citet{MeyrandGaltierPRL12} with the one-chiral-sector-dominated-state (OCSCS) one \citep[][]{hydrochirality} to form a nonlinear extended-magnetohydrodynamics (XMHD) theory for the…

Plasma Physics · Physics 2017-05-12 Jian-Zhou Zhu

According to the kinematic theory of nonhelical dynamo action the magnetic energy spectrum increases with wavenumber and peaks at the resistive cutoff wavenumber. It has previously been argued that even in the dynamical case the magnetic…

Astrophysics · Physics 2009-11-10 Nils Erland L. Haugen , Axel Brandenburg , Wolfgang Dobler

We study mean-field dynamo action in a background linear shear flow by employing pulsed renewing flows with fixed kinetic helicity and nonzero correlation time ($\tau$). We use plane shearing waves in terms of time-dependent exact solutions…

Solar and Stellar Astrophysics · Physics 2020-05-13 Naveen Jingade , Nishant K. Singh

We present a two-loop field-theoretic analysis of incompressible helical magnetohydrodynamics (MHD) in fully developed stationary turbulence. A key feature of helical MHD is the appearance of an infrared-unstable ``mass-like'' term in the…

The nature of dynamo action in shear flows prone to magnetohydrodynamic instabilities is investigated using the magnetorotational dynamo in Keplerian shear flow as a prototype problem. Using direct numerical simulations and Newton's method,…

Solar and Stellar Astrophysics · Physics 2015-05-30 J. Herault , F. Rincon , C. Cossu , G. Lesur , G. I. Ogilvie , P. -Y. Longaretti

The role of shear in alleviating catastrophic quenching by shedding small-scale magnetic helicity through fluxes along contours of constant shear is discussed. The level of quenching of the dynamo effect depends on the quenched value of the…

Astrophysics · Physics 2008-08-08 Axel Brandenburg