  We have studied the evolution of HuBi 1-like planetary nebulae, considering
several stages of mass injection. We have carried out numerical ionization+1D
hydrodynamics+atomic/ionic rate models with our code Coral 1D to reproduce
planetary nebulae that present multiple shells produced by different ejection
events around the ionizing source. Furthermore, we are interested in comparing
numerical simulations with H$\alpha$ and [NII]$\lambda$6584 emission structures
and the position-velocity diagrams observed in HuBi 1. This object also has a
phase where it has drastically decreased the injection of ionized photons
ejected from the source. The result of these different stages of ejection is a
nebula with intense [NII] line emission in the inner part of the planetary
nebula and an extended HII recombination line emission around the central zone.
The model for HuBi 1 shows the capability of our code to explain the
hydrodynamical and photoionization evolution in ionization nebulae. This is our
first step with a 1D code to study these two physical phenomena at the same
time.
