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Related papers: Double-Diffusive Convection

200 papers

We present a hydrodynamic model that captures the essence of granular dynamics in a vibrating bed. We carry out the linear stability analysis and uncover the instability mechanism that leads to the appearance of the convective rolls via a…

adap-org · Physics 2015-06-30 Hisao Hayakawa , Su Yue , Daniel C. Hong

Thermal convection is one of the main mechanisms of heat transport and mixing in stars in general and also in the photospheric layers which emit the radiation that we observe with astronomical instruments. The present lecture notes first…

Solar and Stellar Astrophysics · Physics 2020-02-03 Friedrich Kupka

Many accretion discs have been found to be distorted: either warped due a misalignment in the system, or non-circular as a result of orbital eccentricity or tidal deformation by a binary companion. Warped, eccentric, and tidally distorted…

Solar and Stellar Astrophysics · Physics 2024-09-19 Loren E. Held , Gordon I. Ogilvie

First results of our 3D numerical simulations of thermohaline convection driven by 3He burning in a low-mass RGB star at the bump luminosity are presented. They confirm our previous conclusion that this convection has a mixing rate which is…

Solar and Stellar Astrophysics · Physics 2015-05-20 Pavel A. Denissenkov , William J. Merryfield

The multiscale flow structure in the solar convection zone - the coexistence of such features as the granules, mesogranules, supergranules and giant cells - has not yet been properly understood. Here, the possible role of one physical…

Solar and Stellar Astrophysics · Physics 2018-02-15 O. V. Shcheritsa , A. V. Getling , O. S. Mazhorova

Various instabilities have been proposed as a promising mechanism to accumulate dust. Moreover, some of them are expected to lead to the multiple-ring structure formation and the planetesimal formation in protoplanetary disks. In a…

Earth and Planetary Astrophysics · Physics 2019-08-21 Ryosuke T. Tominaga , Sanemichi Z. Takahashi , Shu-ichiro Inutsuka

In the first paper of this series, we discussed analytically, in an approximate way, the mixing processes which occur in slowly rotating stars when the feed-back effects due to the diffusion-induced $\mu$-gradients are introduced in the…

Astrophysics · Physics 2009-11-07 Sylvie Theado , Sylvie Vauclair

The hydrodynamic processes operating within stellar interiors are far richer than represented by the best stellar evolution model available. Although it is now widely understood, through astrophysical simulation and relevant terrestrial…

Astrophysics · Physics 2009-11-13 Casey A. Meakin

The treatment of mixing processes is still one of the major uncertainties in 1D stellar evolution models. This is mostly due to the need to parametrize and approximate aspects of hydrodynamics in hydrostatic codes. In particular, the effect…

Solar and Stellar Astrophysics · Physics 2017-08-02 Philipp V. F. Edelmann , Friedrich K. Roepke , Raphael Hirschi , Cyril Georgy , Samuel Jones

Hydrodynamic waves propagate through stellar interiors, transporting energy and angular momentum. They can also advect fluid elements to produce mixing, but this effect has not been quantified from first principles. We derive the leading…

Solar and Stellar Astrophysics · Physics 2022-09-20 Adam S. Jermyn

[Abridged] Star and planet formation are the complex outcomes of gravitational collapse and angular momentum transport mediated by protostellar and protoplanetary disks. In this review we focus on the role of gravitational instability in…

Solar and Stellar Astrophysics · Physics 2016-10-05 Kaitlin M. Kratter , Giuseppe Lodato

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 report on the development of an implicit multi-D hydrodynamic code for stellar evolution. We present two test-cases relevant for the first scientific goal of the code: the simulation of convection in pulsating stars. First results on a…

The present study examines the linear instability characteristics of double-diffusive mixed convective flow in a vertical channel with viscosity stratification. The viscosity of the fluid is modelled as an exponential function of…

Fluid Dynamics · Physics 2023-06-28 Ankush , P. A. L. Narayana , K. C. Sahu

Many global circulation models predict supersonic zonal winds and large vertical shears in the atmospheres of short-period jovian exoplanets. Using linear analysis and nonlinear local simulations, we investigate hydrodynamic dissipation…

Earth and Planetary Astrophysics · Physics 2015-05-18 Jason Li , Jeremy Goodman

The processes that govern the evolution of dust and water (in the form of vapor or ice) in protoplanetary disks are intimately connected. We have developed a model that simulates dust coagulation, dust dynamics (settling, turbulent mixing),…

Earth and Planetary Astrophysics · Physics 2016-12-28 Sebastiaan Krijt , Fred J. Ciesla , Edwin A. Bergin

Condensable species are crucial in shaping planetary climate. A wide range of planetary climate systems involve understanding non-dilute condensable substances and their influence on climate dynamics. There has been progress on large-scale…

Earth and Planetary Astrophysics · Physics 2021-12-22 Xianyu Tan , Maxence Lefevre , Raymond Pierrehumbert

In close two-body astrophysical systems, such as binary stars or Hot Jupiter systems, tidal interactions often drive dynamical evolution on secular timescales. Many host stars and presumably giant gaseous planets feature a convective…

Solar and Stellar Astrophysics · Physics 2021-09-20 A. Astoul , A. J. Barker

The variability of the strength of the Atlantic Meridional Overturning Circulation is influenced substantially by the formation of deep water in the North Atlantic. In many ocean models, so-called deep-decoupling oscillations have been…

Dynamical Systems · Mathematics 2024-06-04 John Bailie , Henk A. Dijkstra , Bernd Krauskopf

Two superposed liquid layers display a variety of convective phenomena that are inaccessible in the traditional system where the upper layer is a gas. We consider several pairs of immiscible liquids. Once the liquids have been selected, the…

patt-sol · Physics 2009-10-31 Anne Juel , John M. Burgess , W. D. McCormick , J. B. Swift , Harry L. Swinney