The rigorous derivation of models of complex fluid flows has known a new impluse with the adaptation of homogeneisation methods to the compressible Navier-Stokes equations, in particular by Didier Bresch and Matthieu Hillairet. This approach leads in particular to well-known models, but with appropriate and closed exchange terms. When introducing additional effects, some difficulties arise since the two-phase mixture cannot be decribed by an extended Navier-Stokes model. The mechanisms which lead to average models, meaning model for which the separation of phases no longer hold due to an appropriate downscaling, have to be adapted. We will present the case of the introduction of the surface tension on bubbly flows and the associated averaged two-phase model. This is a joint work with Matthieu Hillairet et Hélène Mathis.