On the determination of response functions for a binary mixture of incompressible Newtonian fluids

Equations governing the motion of a mixture of two incompressible inert Newtonian fluids are presented. Steady two-dimensional solutions are derived, and a method is suggested for determining certain combinations of the coefficients appearing in the constitutive equations. A uniqueness theorem is proved, and its implications for flows with a free surface are considered. Instabilities seem to arise for the flow of mixture films and thus the solutions derived for problems with a free surface may only be valid under certain restrictive conditions.