DYNAMICS OF COLLIDING BINARY STELLAR WINDS - PRESSURE EQUILIBRIUM-MODELS

The dynamical and geometrical aspects of two quasi-radial supersonic counter-streaming gas flows are investigated in the framework of pressure equilibrium models. The numerical results, i.e. the boundary layers derived from the Newtonian approximation (orthogonal momentum conservation) and extended models based on mass and momentum conservation using constant velocity fields and fields with quadratically decreasing acceleration for a hot model (Wolf-Rayet/O-star) binary are compared with analytical approximations of the interface defined as an envelope derived from trajectorial models (two-fixed-centre problem, restricted three-body problem). The numerical integration yields a boundary curve which might be approximated by a hyperboloid. The envelope and the interface corresponding to given fields with quadratically decreasing acceleration fit nearly identically to each other. The results can serve as input data for an analysis of the binary stellar wind problems based on a shock-capturing method.