l) (30 pts) Consider steady, incompressible, laminar flow of a Newtonian fluid in an infinitely long round pipe annulus of inner radius Ri and outer radius Ro. Ignore the effects of gravity A constant negative pressure gradient dP/dz is applied in the z-direction: dP/dz=(P2-P1)/(Z2 - z1) where zi and z are two arbitrary locations along the z-axis, and P and P are the pressures at those two locations. The pressure gradient is caused by a pump. Derive an expression for the velocity field in the annular space in the pipe. Outer pipe wall
Fluid:p,
-
Z
iP1 Ri Ro
- Z2
Z1
aP P2-P1 az Z2-Z1