Evolution of a Viscous Protoplanetary Disk with Convectively Unstable Regions

Abstract

The role of convection in the gas-dust accretion disk around a young star is studied. The evolution of a Keplerian disk is modeled using the Pringle equation, which describes the time variations of the surface density under the action of turbulent viscosity. The distributions of the density and temperature in the polar directions are computed simultaneously in the approximation that the disk is hydrostatically stable. The computations of the vertical structure of the disk take into account heating by stellar radiation, interstellar radiation, and viscous heating. The main factor governing evolution of the disk in this model is the dependence of the viscosity coefficient on the radius of the disk. The computations of this coefficient take into account the background viscosity providing the continuous accretion of the gas and the convective viscosity, which depends on the parameters of the convection at a given radius. The results of computations of the global evolution and morphology of the disk obtained in this approach are presented. It is shown that, in the adopted model, the accretion has burst-like character: after the inner part of the disk ( R < 3 AU) is filled with matter, this material is relatively fast discharged onto the star, after which the process is repeated. Our results may be useful for explaining the activity of young FU Ori and EX Lup objects. It is concluded that convection may be one of the mechanisms responsible for the non-steady pattern of accretion in protostellar disks.

arXiv commentAccepted for publication in Astronomy Reports

References in corpus (17)

• Protoplanetary Disks and Their Evolution
• Dynamics of Protoplanetary Disks
• Turbulence in Accretion Disks. Vorticity Generation and Angular Momentum Transport via the Global Baroclinic Instability
• The Burst Mode of Protostellar Accretion
• Characterising the Gravitational Instability in Cooling Accretion Discs
• 2-D simulations of FU Orionis disk outbursts
• Accretion in protoplanetary disks: the imprint of core properties
• A systematic survey for eruptive young stellar objects using mid-infrared photometry
• Convection Causes Enhanced Magnetic Turbulence in Accretion Disks in Outburst
• Dwarf Nova Outbursts with Magnetorotational Turbulence
• Dust opacity variations in the pre-stellar core L1544
• Knotty protostellar jets as a signature of episodic protostellar accretion?
• Disc wind models for FU Ori objects
• Improving the thin-disk models of circumstellar disk evolution. The 2+1-dimensional model
• A viscous instability in axially symmetric laminar shear flows
• Convection in axially symmetric accretion discs with microscopic transport coefficients
• A viscous-convective instability in laminar Keplerian thin discs. II. Anelastic approximation

Cited by in corpus (6)

• Evolution of dust in protoplanetary disks of eruptive stars
• Discovery of a mid-infrared protostellar outburst of exceptional amplitude
• Simulation of Thermal Surface Waves in a Protoplanetary Disk in a Two-Dimensional Approximation
• Evolution of a Viscous Protoplanetary Disk with Convectively Unstable Regions. II. Accretion Regimes and Long-Term Dynamics
• Simulations of thermal surface waves in a protoplanetary disk using 1+1D approximation
• Evidence of Accretion Burst: The Viscously Heated Inner Disk of the Embedded Protostar IRAS 16316-1540