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A 2D model representing the dynamical interaction of dust and gas in a planetary channel is explored. The two components are treated as interpenetrating fluids in which the gas is treated as a Boussinesq fluid while the dust is treated as…

Astrophysics · Physics 2007-05-23 O. M. Umurhan

The orientational dynamics of inertialess anisotropic particles transported by two-dimensional convective turbulent flows display a coexistence of regular and chaotic features. We numerically demonstrate that very elongated particles (rods)…

Soft Condensed Matter · Physics 2020-03-10 Enrico Calzavarini , Linfeng Jiang , Chao Sun

We show that an alpha effect is driven by the cosmic ray Bell instability exciting left-right asymmetric turbulence. Alfven waves of a preferred polarization have maximally helical motion, because the transverse motion of each mode is…

High Energy Astrophysical Phenomena · Physics 2012-06-21 Igor Rogachevskii , Nathan Kleeorin , Axel Brandenburg , David Eichler

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

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…

We analyse the results of direct numerical simulations of rotating convection in spherical shell geometries with stress-free boundary conditions, which develop strong zonal flows. Both the Ekman number and the Rayleigh number are varied. We…

Fluid Dynamics · Physics 2023-08-11 Justin A. Nicoski , Anne R. O'Connor , Michael A. Calkins

Microscale turbulence in porous media is a new physical phenomenon that exhibits unique properties unlike those in classical turbulence flows. At low values of porosity, the surface forces on the solid obstacles compete with the inertial…

Fluid Dynamics · Physics 2021-08-24 V. Srikanth , C. W. Huang , T. S. Su , A. V. Kuznetsov

Spherical Couette flow (flow between concentric rotating spheres) is one of flows under consideration for the laboratory magnetic dynamos. Recent experiments have shown that such flows may excite Coriolis restored inertial modes. The…

In a recent paper (Phys. Rev. Lett. 94 (2005), 184506; physics/0411050) it was shown that a simple mean-field dynamo model with a spherically symmetric helical turbulence parameter alpha can exhibit a number of features which are typical…

Geophysics · Physics 2007-05-23 Frank Stefani , Gunter Gerbeth , Uwe Guenther , Mingtian Xu

Quasigeostrophic turbulence on a beta-plane with a finite deformation radius is studied nu- merically, with particular emphasis on frequency and combined wavenumber-frequency do- main analyses. Under suitable conditions, simulations with…

Atmospheric and Oceanic Physics · Physics 2016-04-08 D. L. Suhas , Jai Sukhatme

Three-dimensional particle tracking experiments were conducted in a turbulent boundary layer with friction Reynolds number $Re_\tau$ of 700 and 1300. Two finite size spheres with specific gravities of 1.003 (P1) and 1.050 (P2) and diameters…

Fluid Dynamics · Physics 2019-07-02 Yi Hui Tee , Diogo Barros , Ellen K. Longmire

We study the modulational instability of geophysical Rossby and plasma drift waves within the Charney-Hasegawa-Mima (CHM) model both theoretically, using truncated (four-mode and three-mode) models, and numerically, using direct simulations…

Chaotic Dynamics · Physics 2011-05-24 Colm Connaughton , Balu Nadiga , Sergey Nazarenko , Brenda Quinn

This study derives a complete set of equatorially confined wave solutions from an anelastic equation set with the complete Coriolis terms, which include both the vertical and meridional planetary vorticity. The propagation mechanism can…

Atmospheric and Oceanic Physics · Physics 2020-10-20 Hing Ong , Paul E. Roundy

We present a dynamo mechanism arising from the presence of barotropically unstable zonal jet currents in a rotating spherical shell. The shear instability of the zonal flow develops in the form of a global Rossby mode, whose azimuthal…

Geophysics · Physics 2015-04-23 Céline Guervilly , Philippe Cardin , Nathanaël Schaeffer

Resonantly forced spiral waves in excitable media drift in straight-line paths, their rotation centers behaving as point-like objects moving along trajectories with a constant velocity. Interaction with medium boundaries alters this…

Pattern Formation and Solitons · Physics 2014-12-08 Jacob Langham , Irina Biktasheva , Dwight Barkley

Large-scale planetary or stellar magnetic fields generated by a dynamo effect are mostly attributed to flows forced by buoyancy forces in electrically conducting fluid layers. However, these large-scale fields may also be controlled by…

Solar and Stellar Astrophysics · Physics 2015-06-22 David Cébron , Rainer Hollerbach

Cloud cover at the planetary limb of water-rich Earth-like planets is likely to weaken chemical signatures in transmission spectra, impeding attempts to characterize these atmospheres. However, based on observations of Earth and solar…

Earth and Planetary Astrophysics · Physics 2023-07-14 Maureen Cohen , Massimo A. Bollasina , Denis E. Sergeev , Paul I. Palmer , Nathan J. Mayne

We present a study of spectral laws for helical turbulence in the presence of solid body rotation up to Reynolds numbers Re~1*10^5 and down to Rossby numbers Ro~3*10^-3. The forcing function is a fully helical flow that can also be viewed…

Fluid Dynamics · Physics 2009-12-18 J. Baerenzung , D. Rosenberg , P. D. Mininni , A. Pouquet

In recent experiments, Sawaguchi et al. directly probed the lubrication layer of air beneath a droplet levitating inside a rotating cylindrical drum. For small rotation rates of the drum, the lubrication film beneath the drop adopted a…

We report results on the geometrical statistics of the vorticity vector obtained from experiments in electromagnetically forced rotating turbulence. A range of rotation rates $\Omega$ is considered, from non-rotating to rapidly rotating…

Fluid Dynamics · Physics 2013-12-19 Lorenzo Del Castello , Herman J. H. Clercx