  We present hydrodynamical simulations of interacting Coronal Mass Ejections
in the Interplanetary medium (ICMEs). In these events, two consecutive CMEs are
launched from the Sun in similar directions within an interval of time of a few
hours. In our numerical model, we assume that the ambient solar wind is
characterized by its velocity and mass-loss rate. Then, the CMEs are generated
when the flow velocity and mass-loss rate suddenly change, with respect to the
ambient solar wind conditions during two intervals of time, which correspond to
the durations of the CMEs. After their interaction, a merged region is formed
and evolve as a single structure into the interplanetary medium. In this work,
we are interested in the general morphology of this merged region, which
depends on the initial parameters of the ambient solar wind and each of the
CMEs involved. In order to understand this morphology, we have performed a
parametric study in which we characterize the effects of the initial parameters
variations on the density and velocity profiles at 1 AU, using as reference the
well-documented event of July 25th, 2004. Based on this parametrization we were
able to reproduce with a high accuracy the observed profiles. Then, we apply
the parametrization results to the interaction events of May 23, 2010; August
1, 2010; and November 9, 2012. With this approach and using values for the
input parameters within the CME observational errors, our simulated profiles
reproduce the main features observed at 1 AU. Even though we do not take into
account the magnetic field, our models give a physical insight into the
propagation and interaction of ICMEs.
