We consider here the problem of deriving rigorously from renormalized solut
ions of Boltzmann's equation, globally in time, for general initial conditi
ons and without any additional assumption, solutions of Stokes' equations (
together with the strong Boussinesq relation). We also obtain similar resul
ts for Euler equations where, however, we need to make an assumption on the
high velocities of the solutions of Boltzmann's equation.