  We conduct 3D numerical simulations of the winds collision process in the
massive binary system Eta Carinae, and conclude that accretion occurs during
periastron passage. We include radiative cooling of the two winds, one from
each star, and the gravity of the secondary and primary stars. Our new
numerical finding is that at an orbital separation of ~3-4AU, about three weeks
before periastron passage, accretion of dense primary wind gas onto the
secondary star begins. To isolate the basic role of the secondary stellar
gravity, we neglect the orbital motion and the acceleration zone of the primary
wind. Including these effects will strengthen even more our conclusion that
accretion near periastron passage of Eta Car is inevitable. Accretion of the
primary wind gas onto the secondary star for several weeks near periastron
passage accounts for the otherwise puzzling behavior of the binary system near
periastron passage.
