Influence of the approximation viscosity on the numerical solution of the problem on the accretion disk in a binary star system

Abstract

We study the effect of the approximation viscosity of Godunov-type difference schemes in a model problem on the accretion disk in a binary star system. Computations are carried out by schemes of the first and increased approximation order. In the higher-order scheme, we take into account the viscous stress tensor, which is used to model the influence of the approximation viscosity observed in the first-order scheme. It is noteworthy that the approximation viscosity can lead to global qualitative changes in the flows to be modeled. The numerical results given in the paper are of independent interest in that they illustrate some new specific features of gasdynamic flows in this classical problem of modern astrophysics.