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Related papers: Fractal features in accretion discs

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Turbulent Comptonization, a potentially important damping and radiation mechanism in relativistic accretion flows, is discussed. Particular emphasis is placed on the physical basis, relative importance, and thermodynamics of turbulent…

Astrophysics · Physics 2009-11-11 Aristotle Socrates , Shane W. Davis , Omer Blaes

We consider the effects of eccentricity on the fragmentation of gravitationally unstable accretion disks, using numerical hydrodynamics. We find that eccentricity does not affect the overall stability of the disk against fragmentation, but…

Astrophysics · Physics 2011-02-11 R. D. Alexander , P. J. Armitage , J. Cuadra , M. C. Begelman

Aggregation phenomena are ubiquitous in nature, encompassing out-of-equilibrium processes of fractal pattern formation, important in many areas of science and technology. Despite their simplicity, foundational models such as…

Statistical Mechanics · Physics 2016-05-31 J. R. Nicolás-Carlock , J. L. Carrillo-Estrada , V. Dossetti

Using a generalization of vector calculus for space with non-integer dimension, we consider elastic properties of fractal materials. Fractal materials are described by continuum models with non-integer dimensional space. A generalization of…

Materials Science · Physics 2015-03-12 Vasily E. Tarasov

Formation and evolution of fragmentation instabilities in fractal islands, obtained by deposition of silver clusters on graphite, are studied. The fragmentation dynamics and subsequent relaxation to the equilibrium shapes are controlled by…

Materials Science · Physics 2009-11-07 C. Brechignac , Ph. Cahuzac , F. Carlier , C. Colliex , J. Leroux , A. Masson , B. Yoon , U. Landman

An analytic solution is presented to the three-dimensional problem of steady axisymmetric fluid flow through an accretion disk. The solution has been obtained through a systematic expansion in the small parameter epsilon =H/R (the ratio of…

Astrophysics · Physics 2007-05-23 W. Kluzniak , D. Kita

We develop a new definition of fractals which can be considered as an abstraction of the fractals determined through self-similarity. The definition is formulated through imposing conditions which are governed the relation between the…

Metric Geometry · Mathematics 2019-08-13 Marat Akhmet , Ejaily Milad Alejaily

Large scale magnetic field threading an accretion disk is a key ingredient in the jet formation model. The most attractive scenario for the origin of such a large scale field is the advection of the field by the gas in the accretion disk…

High Energy Astrophysical Phenomena · Physics 2015-06-12 Xinwu Cao , H. C. Spruit

Inertial particles advected in chaotic flows often accumulate in strange attractors. While moving in these fractal sets they usually approach each other and collide. Here we consider inertial particles aggregating upon collision. The new…

Fluid Dynamics · Physics 2009-11-13 Jens C. Zahnow , Rafael D. Vilela , Ulrike Feudel , Tamas Tel

The viscous evolution of a thin disc around a central object is considered. Such discs are described by self-similar solutions in which either all or none of the inflowing mass accretes. An approximate solution for the partial accretion…

High Energy Astrophysical Phenomena · Physics 2012-10-22 K. Yavuz Ekşi

A simple multifractal coarsening model is suggested that can explain the observed dynamical behavior of the fractal dimension in a wide range of coarsening fractal systems. It is assumed that the minority phase (an ensemble of droplets) at…

Disordered Systems and Neural Networks · Physics 2009-10-31 Avner Peleg , Baruch Meerson

We study stationary solutions to the continuity equation for weakly compressible flows. These describe non-equilibrium steady states of weakly dissipative dynamical systems. Compressibility is a singular perturbation that changes the steady…

Chaotic Dynamics · Physics 2010-09-14 Itzhak Fouxon

Traditional studies of chaos in conservative and driven dissipative systems have established a correspondence between sensitive dependence on initial conditions and fractal basin boundaries, but much less is known about the relation between…

Chaotic Dynamics · Physics 2017-06-20 Xiaowen Chen , Takashi Nishikawa , Adilson E. Motter

Aerosols under chaotic advection often approach a strange attractor. They move chaotically on this fractal set but, in the presence of gravity, they have a net vertical motion downwards. In practical situations, observational data may be…

Chaotic Dynamics · Physics 2007-06-28 Rafael Dias Vilela , Tamás Tél , Alessandro P. S. de Moura , Celso Grebogi

Accretion disk outbursts, and their subsequent decline, offer a unique opportunity to constrain the physics of angular momentum transport in hot accretion disks. Recent work has centered on the claim by Cannizzo et al. that the exponential…

Astrophysics · Physics 2009-10-30 Ethan T. Vishniac

We introduce a class of flat currents with fractal properties, called fractional currents, which satisfy a compactness theorem and remain stable under pushforwards by H\"older continuous maps. In top dimension, fractional currents are the…

Functional Analysis · Mathematics 2026-04-09 Philippe Bouafia

If a point particle moves chaotically through a periodic array of scatterers the associated transport coefficients are typically irregular functions under variation of control parameters. For a piecewise linear two-parameter map we analyze…

Chaotic Dynamics · Physics 2009-11-10 R. Klages , T. Klauss

For a fissured medium with uncertainty in the knowledge of fractures' geometry, a conservative tangential flow field is constructed, which is consistent with the physics of stationary fluid flow in porous media and an interpolated geometry…

Numerical Analysis · Mathematics 2020-08-21 Fernando A Morales , Jorge M Ramírez

The relationship between geometric and dynamic properties of fractal-like aggregates is studied in the continuum mass and momentum-transfer regimes. The synthetic aggregates were generated by a cluster-cluster aggregation algorithm. The…

Soft Condensed Matter · Physics 2013-11-13 Anastasios D. Melas , Lorenzo Isella , Athanasios G. Konstandopoulos , Yannis Drossinos

The purpose of this paper is to explore the dynamical behaviour of hot accretion flow with thermal conduction. The importance of thermal conduction on hot accretion flow is confirmed by observations of the hot gas that surrounds Sgr A$^*$…

High Energy Astrophysical Phenomena · Physics 2012-05-11 Kazem Faghei
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