Percolating Winds through a Clumpy Torus

By way of axisymmetric numerical hydrodynamical simulations we study the interaction of a fast tenuous stellar wind with a thick toroidal distribution of high-density clouds embedded in a stationary intercloud medium with a power-law density fall-off of index −1.9. We find that the supersonic wind percolates through the cloud ensemble, producing finger-like structures in the contact discontinuity. We also find that such a toroidal distribution of clouds is sufficient to collimate a jet-like outflow along the symmetry axis. After the start of the interaction with the stellar wind, cometary tails in the outer region temporarily tend to be short and hollow, whereas older tails are long and filled with ablated high-density gas.