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Related papers: On the Helium fingers in the intracluster medium

200 papers

Iron-rich layers are known to form in the stellar subsurface through a combination of gravitational settling and radiative levitation. Their presence, nature and detailed structure can affect the excitation process of various stellar…

Solar and Stellar Astrophysics · Physics 2015-06-22 Varvara Zemskova , Pascale Garaud , Morgan Deal , Sylvie Vauclair

Stably stratified layers are thought to develop at the top of the liquid metallic cores of many terrestrial planets. We consider the case where the thermal gradient is stable but the compositional gradient is unstable, a situation…

Fluid Dynamics · Physics 2025-11-17 Martin Gray , Celine Guervilly , Graeme Sarson

Depending on the topology of the magnetic field and characteristics of turbulent motions, diffusion can significantly affect the distribution of elements, in particular helium, in the intracluster medium (ICM). As has been noted previously,…

High Energy Astrophysical Phenomena · Physics 2015-11-25 P. Medvedev , M. Gilfanov , S. Sazonov , P. Shtykovskiy

We study the dynamics of salt fingers in the regime of slow salinity diffusion (small inverse Lewis number) and strong stratification (large density ratio), focusing on regimes relevant to Earth's oceans. Using three-dimensional direct…

Fluid Dynamics · Physics 2025-10-01 Adrian E. Fraser , Adrian van Kan , Edgar Knobloch , Keith Julien , Chang Liu

A thin solid (e.g., paper), burning against an oxidizing wind, develops a fingering instability with two decoupled length scales. The spacing between fingers is determined by the P\'eclet number (ratio between advection and diffusion). The…

Condensed Matter · Physics 2009-10-30 O. Zik , Z. Olami , E. Moses

In a binary fluid mixture, the concentration gradient of a heavier molecular solute leads to a diffusive flux of solvent and solute to achieve thermodynamic equilibrium. If the solute concentration decreases with height, the system is…

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 demonstrate experimentally the existence of a purely elastic fingering instability which arises when air penetrates into an elastomer confined in a Hele-Shaw cell. Fingers appear sequentially and propagate within the bulk of the material…

Soft Condensed Matter · Physics 2016-01-19 Baudouin Saintyves , Olivier Dauchot , Elisabeth Bouchaud

We investigate the development of mobility inversion and fingering when a granular suspension is injected radially between horizontal parallel plates of a cell filled with a miscible fluid. While the suspension spreads uniformly when the…

Fluid Dynamics · Physics 2021-01-01 Arshad Kudrolli , Rausan Jewel , Ram Sudhir Sharma , Alexander P. Petroff

Viscous fingering patterns can form at the interface between two immiscible fluids confined in the gap between a pair of flat plates; whenever the fluid with lower viscosity displaces the one of higher viscosity the interface is unstable.…

Fluid Dynamics · Physics 2019-04-03 Thomas E. Videbæk , Sidney R. Nagel

Understanding whether Helium can sediment to the core of galaxy clusters is important for a number of problems in cosmology and astrophysics. All current models addressing this question are one-dimensional and do not account for the fact…

Cosmology and Nongalactic Astrophysics · Physics 2015-10-28 Thomas Berlok , Martin E. Pessah

Using air to displace a viscous fluid contained in Hele-Shaw cell can create a fingering pattern at the interface between the fluids, if the capillary number exceeds a critical value. This Saffman-Taylor instability is revisited for the…

Fluid Dynamics · Physics 2016-08-03 Ilyesse Bihi , Michael Baudoin , Jason E. Butler , Christine Faille , Farzam Zoueshtiagh

We consider the role of diffusion in the redistribution of elements in the hot interstellar medium (ISM) of early-type galaxies. It is well known that gravitational sedimentation can affect significantly the abundances of helium and heavy…

High Energy Astrophysical Phenomena · Physics 2018-02-12 P. Medvedev , S. Sazonov , M. Gilfanov

The Saffman-Taylor viscous fingering instability occurs when a less viscous fluid displaces a more viscous one between narrowly spaced parallel plates in a Hele-Shaw cell. Experiments in radial flow geometry form fan-like patterns, in which…

Soft Condensed Matter · Physics 2009-10-30 Jose A. Miranda , Michael Widom

Double-diffusive convection refers to mixing where the effects of thermal and composition gradients compete to determine the stability of a fluid. In addition to the familiar fast convective instability, such fluids exhibit the slow, direct…

Astrophysics · Physics 2015-06-24 Scott A. Grossman , Ronald E. Taam

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

A rest fluid displaced by a less viscous fluid in a porous medium triggers the so-called Saffman-Taylor instability at their contact front and hence forms complicated finger-like patterns. When the two fluids are miscible, the surface…

Fluid Dynamics · Physics 2018-09-26 Lang Xia

We have developed a formalism for analyzing the stability of a fluid in the presence of neutrinos of all flavors and in the presence of a gravitational field. When applied to an extensive two-dimensional grid of core radii and fluid element…

Astrophysics · Physics 2009-09-29 S. W. Bruenn , E. A. Raley , A. Mezzacappa

A simple model of nonlinear salt-finger convection in two dimensions is derived and studied. The model is valid in the limit of small solute to heat diffusivity ratio and large density ratio, which is relevant to both oceanographic and…

Fluid Dynamics · Physics 2017-03-13 Jin-Han Xie , Benjamin Miquel , Keith Julien , Edgar Knobloch

We consider the steady-state fingering instability of an elastic membrane separating two fluids of different density under external pressure in a rotating Hele-Shaw cell. Both inextensible and highly extensible membranes are considered, and…

Fluid Dynamics · Physics 2023-07-05 Benjamin Foster , Edgar Knobloch