Air conditioning on a university campus is provided by chilled water (10oC) pumped through a main supply pipe. The pipe makes a loop 5 km in length. The pipe diameter is 0.75 m and the material is steel. The maximum design volume flow rate is 0.65 m3/s. The circulating pump is driven by an electric motor. The efficiencies of pump and motor are ?p = 85 and ?m = 85, respectively. Electricity cost is 14?/(kW.hr). Determine (a) the pressure drop, (b) the rate of energy addition to the water, and (c) the daily cost of electrical energy for pumping.
This question is from Introduction to Fluid Mechanics 8th edition by Fox, McDonald, Pritchard (8.178)