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Numerical Simulations of Convective Accretion Flows in Three Dimensions

Igor V. Igumenshchev·Marek A. Abramowicz·Ramesh Narayan
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Abstract

Advection-dominated accretion flows (ADAFs) are known to be convectively unstable for low values of the viscosity parameter alpha. Two-dimensional axisymmetric hydrodynamic simulations of such flows reveal a radial density profile which is significantly flatter than the rho~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.

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Igor V. Igumenshchev, Marek A. Abramowicz, Ramesh Narayan. 2000-04-01. Numerical Simulations of Convective Accretion Flows in Three Dimensions. https://doi.org/10.1086/312755

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