Problem HW2P2 Conditioned air at a temperature of 13 °C and a flow rate of 5000 L/s is supplied through a sheet metal duct to the zones in a commercial office

building. The supply duct is rectangular in cross-section (300 mm x 600 mm), 500 m long, with an equivalent roughness of 0.0001 m. The sum of the fitting losses due to bends and dampers in the ductwork is equal to 800 hydraulic duct diameters. There is a cooling coil with a pressure drop of 150 Pa. The fan motor efficiency is 85 % and the fan efficiency is 75 %. Determine the motor power for the supply fan.