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Numerical Computation of Two Dimensional Wind Accretion of Isothermal Gas

Eiji Shima·Takuya Matsuda·Ulrich Anzer·Gerhard Borner·Henri M. J. Boffin
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Abstract

A new numerical algorithm for calculating isothermal wind accretion flows has been developed and is applied here to the analysis of the hydrodynamics of two-dimensional plane symmetric accretion flows in wind-fed sources. Polar coordinates are used to ensure fine resolution near the object. It is found that a thin accretion column is formed which shows wave-like oscillations. Small accretion disks are formed temporarily around the object. Mass accretion rate and angular momentum accretion rate exhibit quasi-periodic oscillations. The amplitudes of the oscillations depend on the size of the inner boundary, the number of grid points and the method of calculation. For a smaller size of the inner boundary, finer grids and more accurate numerical schemes, the amplitudes of the oscillation become larger.

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Eiji Shima, Takuya Matsuda, Ulrich Anzer, Gerhard Borner, Henri M. J. Boffin. 1998-05-28. Numerical Computation of Two Dimensional Wind Accretion of Isothermal Gas. https://arxiv.org/abs/astro-ph/9805343

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