  This work is devoted to the problem of boundary stabilization of a mixture of
two viscous and incompressible fluids in a three dimensional channel-like
domain $(x,y,z)\in \mathbb{R}\times (0,1)\times\mathbb{R}$. The model consists
of the Navier-Stokes equations, governing the fluid velocity, coupled with a
convective Cahn-Hilliard equation for the relative density of the atoms of one
of the fluids. The feedback controller, we design here, is with actuation only
on the tangential component of the velocity field on both walls $y=0,1$.
Moreover, it is given in a simple and explicit form, easy to manipulate from
the computational point of view. The stability is guaranteed no matter how
large the kinematic viscosity of the mixture is. Also it is independent of the
other coefficients of the system.
