Hydrodynamical Models of Pulsar wind Bow-Shock Nebulae

We present hydrodynamical simulations, using a 2-D two fluid model, of bow shocks in a representative regime for pulsar wind driven bow-shock nebulae. We also investigate the behaviour of a passive toroidal magnetic field wounded around the pulsar velocity direction. Moreover we estimate the opacity of the bow-shock to penetration of ISM neutral hydrogen. Finally we compare these numerical results with those from an analytical model.