Fine mesh calculations of dwarf nova outbursts
K. Ludwig and
Received 30 June 1997 / Accepted 4 August 1997
We present new results from fine mesh calculations of dwarf nova outbursts. The vertical thermal and the radial viscous evolution of the accretion disk is followed simultaneously. This is essential for determining formation, structure, and propagation of transition fronts which are a fundamental constituent of the dwarf nova cycle. In addition to the equation of continuity of mass flow and the energy equation, we have solved the Navier-Stokes equations for the radial and the azimuthal velocity. This allows us to follow deviations of the azimuthal velocity from the Keplerian value. Results show, that these deviations are largest inside heating waves, but have only marginal influence on the outburst behavior. More important are the effects of lateral heat diffusion which cause an enlargement of the radial width of a heating wave. This leads to essential changes in the long-term evolution of the accretion disk. We compare our new results with earlier results (Ludwig et al. 1994), where we used the localized front approximation (Meyer 1984) and with results of fine mesh calculations of Mineshige (1987) and Cannizzo (1993).
Key words: accretion, accretion disk cataclysmic variables instabilities stars: individual: VW Hydri
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© European Southern Observatory (ESO) 1998
Online publication: December 8, 1997