Question

10. Immiscible fluids Two immiscible incompressible Newtonian fluids flow together through in thedirection two lates separated by a distance H in the y-direction. Let us make thé top plate /move with ection while fixing the bottom plate. At steady state, however, there be a little slip velocity of the more dense fluid only at the lower boundary The flow constant vetocity V in the x-dir is ynidirectional and faminar. For convenience, we take that x is the flow direction and y the velocity gradient direction. There is no pressure difference between the inlet and outlet, and the gap thickness (H) between the plates is so small that gravitational force can be neglected. (a) Sketch the steady-state velocity profile qualitatively in case that the less dense fluid has a lower viscosity. What about the opposite case? (b) When the less dense fluid has a viscosity twice as large as that of the more dense fluid, Sketch the steady-state velocity profile qualitatively and compare between the two fluids for the magnitude of heat generated by viscous dissipation.

Answer 1

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