The space between two coaxial cylinders is filled with an incompressible fluid at constant temperature. The radii of the inner and outer wetted surfaces are ᴋR and R, respectively. The angular velocities of rotation of the inner and outer cylinders are ωi and ωo.
Determine the velocity distribution in the fluid, and the torques exerted by the fluid on the two cylinders needed to maintain the motion.

An open feedwater heater operates at steady state with liquid entering at inlet 1 with t? = 40°c and pl = 1 .2 mpa. water vapor att2-200°c and p2 = 1.2 mpa enters at inlet 2. saturated liquid water exits with a pressure of pa 1.2 mpa. neglect heat transfer with the surroundings and all kinetic and potential energy effects, determine the mass flow rate of steam at inlet 2 if the mass flow rate of liquid water at inlet 1 is given as 2 kg/s.