  We prove global existence of weak solutions for a version of one velocity
Baer-Nunziato system with dissipation describing a mixture of two non
interacting viscous compressible fluids in a piecewise regular Lipschitz domain
with general inflow/outfow boundary conditions. The geometrical setting is
general enough to comply with most current domains important for applications
as, for example, (curved) pipes of picewise regular and axis-dependent cross
sections. As far as the existence proof is concerned, we adapt to the system
the nowaday's classical Lions-Feireisl approach to the compressible
Navier-Stokes equations which is combined with a generalization of the theory
of renormalized solutions to the transport equations in the spirit of
Vasseur-Wen-Yu. The results related to the families of transport equations
presented in this paper extend/improve some of statements of the theory of
renormalized solutions, and they are therefore of independent interest.
