Modified viscosity in accretion disks
نویسندگان
چکیده
منابع مشابه
Viscosity mechanisms in accretion disks
The self-sustained turbulence that develops in magnetized accretion disks is suppressed in the weakly ionized, quiescent disks of close binary stars. Because accretion still proceeds during quiescence, another viscosity mechanism operates in these systems. An anticorrelation of the recurrence times of SU UMa dwarf novae with their mass ratio supports spiral waves or shockwaves tidally induced b...
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We show that the standard model for geometrically thin accretion disks (α-disks) leads to inconsistencies if selfgravity plays a role. This problem arises from the parametrization of viscosity in terms of local sound velocity and vertical disk scale height. A viscosity prescription based on turbulent flows at the critical effective Reynolds number allows for consistent models of thin selfgravit...
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We suggest that the low viscosity in close binary accretion disks during quiescence is due to magnetic fields from the companion star. In very late evolutionary phase the companion stars become brown dwarfs and have cooled down to such low a temperature that this process cannot work anymore. The extremely low viscosity in WZ Sge stars supports this connection between companion stars and viscosi...
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We study the evolution of viscous, isothermal, rotating, thin, axisymmetric accretion disks around a compact object using Smoothed Particle Hydrodynamics. We emphasize the effects of different choices of viscosity prescriptions on the evolution of angular momentum as well as other physical quantities of the disk. We show that a flow with the Shakura-Sunyaev viscosity prescription may produce on...
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ژورنال
عنوان ژورنال: Astronomy & Astrophysics
سال: 2017
ISSN: 0004-6361,1432-0746
DOI: 10.1051/0004-6361/201629672