Spectral Methods for Time-Dependent Studies of Accretion Flows. I. Two-dimensional, Viscous, Hydrodynamic Disks
نویسندگان
چکیده
We present a numerical method for studying the normal modes of accretion flows around black holes. In this first paper, we focus on two-dimensional, viscous, hydrodynamic disks in pseudo-Newtonian potentials, for which the linear modes have been calculated analytically in previous investigations. We use a pseudo-spectral algorithm to evolve the hydrodynamic equations and devise a number of test problems to validate its implementation. We demonstrate the ability of the spectral method to handle accurately non-reflective boundary conditions and to reproduce correctly the stability criteria for differentially rotating hydrodynamic flows. Subject headings: accretion disks, black hole physics, hydrodynamics
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