  In this paper, we present two-dimensional gas dynamic simulations of the
formation and evolution of the eta-Car bipolar outflows. Adopting the
interacting nonspherical winds model, we have carried out high-resolution
numerical simulations, which include explicitly computed time-dependent
radiative cooling, for different possible scenarios of the colliding winds. In
our simulations, we consider different degrees of non-spherical symmetry for
the pre-outburst wind and the great eruption of the 1840s presented by the
eta-Car wind. From these models, we obtain important differences in the shape
and kinematical properties of the Homunculus structure. In particular, we find
an appropriate combination of the wind parameters (that control the degree of
non-spherical symmetry) and obtain numerical experiments that best match both
the observed morphology and the expansion velocity of the eta-Car bipolar
shell. In addition, our numerical simulations show the formation of a bipolar
nebula embedded within the Homunculus (the little Homunculus) developed from a
secondary eruptive event suffered by the star in the 1890s, and also the
development of tenuous, high velocity ejections in the equatorial region that
result from the impact of the eruptive wind of the 1840s with the pre-outburst
wind and that could explain some of the high speed features observed in the
equatorial ejecta. The models were, however, unable to produce equatorial
ejections associated to the second eruptive event.
