A pump draws 20 kW of electrical power while pumping oil with a density of 780 kg/m^3 at a flow rate of 0.3 m^3/s. The diameters of the inlet and outlet pipes of the pump are 7 cm and 12 cm, respectively. Since the pressure increase in the pump is 220 kPa and the motor efficiency is 91%, determine the mechanical efficiency of the pump. (Ignore the kinetic energy correction factor, α=1, Ignore the height differences inside the pump, the head loss in the pump hL=0.5

A pump draws 20 kW of electrical power while pumping oil with a density of 780 kg/m^3 at a flow rate of 0.3 m^3/s. The diameters of the inlet and outlet pipes of the pump are 7 cm and 12 cm, respectively. Since the pressure increase in the pump is 220 kPa and the motor efficiency is 91%, determine the mechanical efficiency of the pump. (Ignore the kinetic energy correction factor, α=1, Ignore the height differences inside the pump, the head loss in the pump hL=0.5

Principles of Heat Transfer (Activate Learning with these NEW titles from Engineering!)

8th Edition

ISBN:9781305387102

Author:Kreith, Frank; Manglik, Raj M.

Publisher:Kreith, Frank; Manglik, Raj M.

Chapter5: Analysis Of Convection Heat Transfer

Section: Chapter Questions

Problem 5.37P

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