9. A Couette pump consists of an inner cylinder and a baffled entrance and exit. Assuming zero circumferential pressure gradient and (a – b) « a (linear, Couette profile), derive formulas for the volume flow and pumping power per unit depth. Plug in the viscosity and density of SAE 30 Oil at 20°C [0.29 kg/m.s] with a = 10 cm, b = 9 cm, and w = 60 rpm.

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