Numerical Simulations of Convective Accretion Flows in Three Dimensions
نویسندگان
چکیده
Advection-dominated accretion flows (ADAFs) are known to be convectively unstable for low values of the viscosity parameter α. Two-dimensional axisymmetric hydrodynamic simulations of such flows reveal a radial density profile which is significantly flatter than the ρ ∝ r−3/2 expected for a canonical ADAF. The modified density profile is the result of inward transport of angular momentum by axisymmetric convective eddies. We present three-dimensional hydrodynamic simulations of convective ADAFs which are free of the assumption of axisymmetry. We find that the results are qualitatively and quantitatively similar to those obtained with two-dimensional simulations. In particular, the convective eddies are nearly axisymmetric and transport angular momentum inward. Subject headings: accretion, accretion disks — black hole physics — convection — hydrodynamics — turbulence
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