In this paper , we present a detailed hydrodynamical study of the properties of the flow produced by the collision of a pulsar wind with the surrounding in a binary system .
This work is the first attempt to simulate interaction of the ultrarelativistic flow ( pulsar wind ) with the nonrelativistic stellar wind .
Obtained results show that the wind collision could result in the formation of an ” unclosed ” ( at spatial scales comparable to the binary system size ) pulsar wind termination shock even when the stellar wind ram pressure exceeds significantly the pulsar wind kinetical pressure .
Moreover , the post-shock flow propagates in a rather narrow region , with very high bulk Lorentz factor ( \gamma \sim 100 ) .
This flow acceleration is related to adiabatical losses , which are purely hydrodynamical effects .
Interestingly , in this particular case , no magnetic field is required for formation of the ultrarelativistic bulk outflow .
The obtained results provide a new interpretation for the orbital variability of radio , X-ray and gamma-ray signals detected from binary pulsar system PSR 1259-63/SS2883 .