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Related papers: Fingering convection in a spherical shell

200 papers

We present a high-resolution, highly stratified numerical simulation of rotating thermal convection in a spherical shell. Our aim is to study in detail the processes that can maintain a near surface shear layer (NSSL) as inferred from…

Solar and Stellar Astrophysics · Physics 2015-06-23 H. Hotta , M. Rempel , T. Yokoyama

Anelastic convection at high Rayleigh number in a plane parallel layer with no slip boundaries is considered. Energy and entropy balance equations are derived, and they are used to develop scaling laws for the heat transport and the…

Fluid Dynamics · Physics 2023-06-22 Chris A. Jones , Krzysztof A. Mizerski , Mouloud Kessar

In planetary fluid cores, the density depends on temperature and chemical composition, which diffuse at very different rates. This leads to various instabilities, bearing the name of double-diffusive convection. We investigate rotating…

Fluid Dynamics · Physics 2019-09-04 Rémy Monville , Jérémie Vidal , David Cébron , Nathanaël Schaeffer

Mixing processes in stars driven by composition gradients as a result of the Rayleigh-Taylor instability are not anticipated. They are supported only by hydrodynamic studies of stellar convection. We find that such mixing occurs below the…

Solar and Stellar Astrophysics · Physics 2015-03-17 Miroslav Mocak , Ewald Mueller

We provide a rigorous analysis of the self-similar solution of the temporal turbulent boundary layer, recently proposed in [2], in which a body force is used to maintain a statistically steady turbulent boundary layer with periodic boundary…

Fluid Dynamics · Physics 2024-06-17 Andrew Wynn , Saeed Parvar , Joseph O Connor , Sylvain Laizet

The dynamics of convecting fluids in rotating spherical shells is governed at Prandtl numbers of the order unity by the interaction between differential rotation and roll-like convection eddies. While the differential rotation is driven by…

Fluid Dynamics · Physics 2009-05-25 F. H. Busse , R. D. Simitev

We report flow measurements in rotating Rayleigh--B\'enard convection in the rotationally-constrained geostrophic regime. We apply stereoscopic particle image velocimetry to measure the three components of velocity in a horizontal…

We consider stability of steady convective flows in a horizontal layer with stress-free boundaries, heated below and rotating about the vertical axis, in the Boussinesq approximation (the Rayleigh-Benard convection). The flows under…

Fluid Dynamics · Physics 2015-06-26 O. M. Podvigina

Steady two-dimensional Rayleigh--B\'enard convection between stress-free isothermal boundaries is studied via numerical computations. We explore properties of steady convective rolls with aspect ratios $\pi/5\le\Gamma\le4\pi$, where…

Fluid Dynamics · Physics 2021-06-30 Baole Wen , David Goluskin , Matthew LeDuc , Gregory P. Chini , Charles R. Doering

Double-diffusive convection driven by both thermal and compositional buoyancy in a rotating spherical shell can exhibit a rather large number of behaviours often distinct from that of the single diffusive system. In order to understand how…

Fluid Dynamics · Physics 2020-04-28 Luis Silva , James F. Mather , Radostin D. Simitev

A three-layer asymptotic structure for turbulent pipe flow is proposed, revealing in terms of intermediate variables, the existence of a Reynolds-number invariant logarithmic region. It provides a theoretical foundation for addressing…

Fluid Dynamics · Physics 2021-07-01 Sourabh S. Diwan , Jonathan F. Morrison

Using experiments and a depth-averaged numerical model, we study instabilities of two-phase flows in a Hele-Shaw channel with an elastic upper boundary and a non-uniform cross-section prescribed by initial collapse. Experimentally, we find…

Fluid Dynamics · Physics 2024-03-04 J. V. Fontana , C. Cuttle , D. Pihler-Puzovic , A. L. Hazel , A. Juel

(abidged) Context: Stellar convection zones are characterized by vigorous high-Reynolds number turbulence at low Prandtl numbers. Aims: We study the dynamo and differential rotation regimes at varying levels of viscous, thermal, and…

Solar and Stellar Astrophysics · Physics 2017-02-22 P. J. Käpylä , M. J. Käpylä , N. Olspert , J. Warnecke , A. Brandenburg

The displacement of a more viscous fluid by a less viscous one in a quasi-two dimensional geometry leads to the formation of complex fingering patterns. This fingering has been characterized by a most unstable wavelength, $\lambda_c$, which…

Fluid Dynamics · Physics 2015-01-30 Irmgard Bischofberger , Radha Ramachandran , Sidney R. Nagel

We investigate the convective stability of a thin, infinite fluid layer with a rectangular cross-section, subject to imposed heat fluxes at the top and bottom and fixed temperature along the vertical sides. The instability threshold depends…

We sandwich a colloidal gel between two parallel plates and induce a radial flow by lifting the upper plate at a constant velocity. Two distinct scenarios result from such a tensile test: ($i$) stable flows during which the gel undergoes a…

Soft Condensed Matter · Physics 2020-08-10 Thibaut Divoux , Asheesh Shukla , Badis Marsit , Yacouba Kaloga , Irmgard Bischofberger

Dynamos driven by rotating convection in the plane layer geometry are investigated numerically for a range of Ekman number ($E$), magnetic Prandtl number ($Pm$) and Rayleigh number ($Ra$). The primary purpose of the investigation is to…

Fluid Dynamics · Physics 2022-11-23 Ming Yan , Michael A. Calkins

Two-dimensional direct numerical simulations are conducted for convection sustained by uniform internal heating in a horizontal fluid layer. Top and bottom boundary temperatures are fixed and equal. Prandtl numbers range from 0.01 to 100,…

Fluid Dynamics · Physics 2015-03-13 David Goluskin , Edward A. Spiegel

The finger-like branching pattern that occurs when a less viscous fluid displaces a more viscous one confined between two parallel plates has been widely studied as a classical example of a mathematically-tractable hydrodynamic instability…

Soft Condensed Matter · Physics 2007-12-13 Xiang Cheng , Lei Xu , Aaron Patterson , Heinrich M. Jaeger , Sidney R. Nagel

Traditional mathematical models of Hele--Shaw flow consider the injection (or withdrawal) of an air bubble into (or from) an infinite body of viscous fluid. The most commonly studied feature of such a model is how the Saffman-Taylor…

Fluid Dynamics · Physics 2023-01-19 Liam C. Morrow , Nicolas De Cock , Scott W. McCue