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Related papers: Mixing through shear instabilities

200 papers

In recent years much interest has been shown in the process of thermohaline mixing in red giants. In low and intermediate mass stars this mechanism first activates at the position of the bump in the luminosity function, and has been…

Solar and Stellar Astrophysics · Physics 2015-06-23 John Lattanzio , Lionel Siess , Ross Church , George Angelou , Richard Stancliffe , Carolyn Doherty , Thomas Stephen , Simon Campbell

We study the linear theory of Kelvin-Helmholtz instability in a layer of ions and neutrals with finite thickness. In the short wavelength limit the thickness of the layer has a negligible effect on the growing modes. However, perturbations…

Astrophysics · Physics 2008-11-26 Mohsen Shadmehri , Turlough P. Downes

Linear stability analysis of strongly coupled incompressible dusty plasma in presence of shear flow has been carried out using Generalized Hydrodynamical(GH) model. With the proper Galilean invariant GH model, a nonlocal eigenvalue analysis…

Plasma Physics · Physics 2015-06-17 D. Banerjee , M. S. Janaki , N. Chakrabarti

We argue that self-excited instabilities are the cause of spiral patterns in simulations of unperturbed stellar discs. In previous papers, we have found that spiral patterns were caused by a few concurrent waves, which we claimed were…

Astrophysics of Galaxies · Physics 2019-08-14 J. A. Sellwood , Ray G. Carlberg

Radiative mixing layers arise wherever multiphase gas, shear, and radiative cooling are present. Simulations show that in steady state, thermal advection from the hot phase balances radiative cooling. However, many features are puzzling.…

Astrophysics of Galaxies · Physics 2021-07-12 Brent Tan , S. Peng Oh , Max Gronke

In order to investigate the possible influence of rotation on the efficiency of the first dredge-up we determined atmospheric parameters, masses, and abundances of carbon, nitrogen, and oxygen in a sample of evolved intermediate mass stars.…

Astrophysics · Physics 2009-11-11 R. Smiljanic , B. Barbuy , J. R. De Medeiros , A. Maeder

We describe the dynamics of a stream of equally spaced macroscopic particles in orbit around a central body (e.g. a planet or star). A co-orbital configuration of small bodies may be subject to gravitational instability, which takes the…

Earth and Planetary Astrophysics · Physics 2015-06-04 Henrik N. Latter , Hanno Rein , Gordon I. Ogilvie

Stellar rotation produces an internal mixing of the elements due to shear instability and meridional circulation. This leads to observable $N/C$ enhancements in massive stars above about 7--9 $M_{\odot}$. Rotation also favours mass loss by…

Astrophysics · Physics 2007-05-23 André Maeder , Georges Meynet , Raphael Hirschi

Thermohaline mixing has been recently identified as the probable dominating process that governs the photospheric composition of low-mass bright giant stars. Here we present the predictions of stellar models computed with the code STAREVOL…

Solar and Stellar Astrophysics · Physics 2015-05-30 C. Charbonnel , N. Lagarde , P. Eggenberger

We consider so-called Leray regularization of the convective contributions. This gives rise to a subgrid parameterization which involves both explicit filtering and (approximate) inversion. The Leray model also arises from the…

Chaotic Dynamics · Physics 2007-05-23 Bernard J. Geurts , Darryl D. Holm

The Kelvin-Helmholtz instability is a ubiquitous physical process in ordinary fluids and plasmas, frequently observed also in space environments. In this paper, kinetic effects at proton scales in the nonlinear and turbulent stage of the…

Space Physics · Physics 2023-07-12 A. Settino , F. Malara , O. Pezzi , M. Onofri , D. Perrone , F. Valentini

Robust arguments predict that a hadron-quark mixed phase may exist in the cores of some "neutron" stars. Such a phase forms a crystalline lattice with a shear modulus higher than that of the crust due to the high density and charge…

Solar and Stellar Astrophysics · Physics 2013-06-18 Nathan K. Johnson-McDaniel , Benjamin J. Owen

Analysis of the saturation of the Kelvin-Helmholtz (KH) instability is undertaken to determine the extent to which the conjugate linearly stable mode plays a role. For a piecewise-continuous mean flow profile with constant shear in a fixed…

Plasma Physics · Physics 2017-06-16 A. E. Fraser , P. W. Terry , E. G. Zweibel , M. J. Pueschel

The purpose of this paper is to improve the modelization of the rotational mixing which occurs in stellar radiation zones, through the combined action of the thermally driven meridional circulation and of the turbulence generated by the…

Astrophysics · Physics 2009-11-10 S. Mathis , J. -P. Zahn

We study Kelvin-Helmholtz (KH) instability at the interface of a disc and corona system by doing a linear perturbation analysis. The disc is assumed to be thin, however, the corona is considered to be nearly quasispherical because of its…

Astrophysics of Galaxies · Physics 2015-05-18 Mohsen Shadmehri , Perikles Rammos

We provide the possible resolution for the century old problem of hydrodynamic shear flows, which are apparently stable in linear analysis but shown to be turbulent in astrophysically observed data and experiments. This mismatch is noticed…

High Energy Astrophysical Phenomena · Physics 2016-10-26 Sujit Kumar Nath , Banibrata Mukhopadhyay

Observations show various jets in the solar atmosphere with significant rotational motions, which may undergo instabilities leading to heat ambient plasma. We study the Kelvin-Helmholtz (KH) instability of twisted and rotating jets caused…

Solar and Stellar Astrophysics · Physics 2015-11-11 T. V. Zaqarashvili , I. Zhelyazkov , L. Ofman

One prototypical instability in granular flows is the shear-banding instability, in which a uniform granular shear flow breaks into alternating bands of dense and dilute clusters of particles having low and high shear (shear stress or shear…

Soft Condensed Matter · Physics 2019-09-18 Priyanka Shukla , Lima Biswas , Vinay Kumar Gupta

The KelvinHelmholtz (KH) instability is a fundamental wave instability that is frequently observed in all kinds of shear layer (jets, wakes, atmospheric air currents etc). The study of KH-instability, coherent flow structures has a major…

Computational Engineering, Finance, and Science · Computer Science 2015-03-29 Santosh Tirunagari

Turbulence generation mechanisms in stratified, rotating flows past three-dimensional (3D) topography remain underexplored, particularly in submesoscale (SMS) regimes critical to geophysical applications. Using turbulence-resolving…

Fluid Dynamics · Physics 2025-09-09 Jinyuan Liu , Pranav Puthan , Sutanu Sarkar