Three-dimensional structure of an alpha accretion disk

W. Kluzniak; D. Kita

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arXiv · astro-ph/0006266

Three-dimensional structure of an alpha accretion disk

W. Kluzniak·D. Kita

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Abstract

An analytic solution is presented to the three-dimensional problem of steady axisymmetric fluid flow through an accretion disk. The solution has been obtained through a systematic expansion in the small parameter epsilon =H/R (the ratio of disk thickness to its radial dimension) of the equations of viscous hydrodynamics. The equation of state was assumed to be polytropic. For all values alpha< 0.685 of the viscosity parameter, we find significant backflow in the midplane of the disk occuring at all radii larger than a certain value; however, in the inner regions of the disk the fluid always flows toward the accreting object. The region of backflow is separated from the region of inflow by a surface flaring outwards from a circular locus of stagnation points situated in the midplane of the disk.

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W. Kluzniak, D. Kita. 2000-06-20. Three-dimensional structure of an alpha accretion disk. https://arxiv.org/abs/astro-ph/0006266

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