Question

For offshore oil rigs, a natural source for fighting fires is the seawater around them. You are tasked with sizing the pump with an efficiency of 80% for a new rig's fire protection system. The pipe in the ocean is 70-cm in diameter. Once to the rig deck, the water will flow through a hose that is 10 meters in length and exit a nozzle that is 10-cm in diameter. The seawater has a density of 1030 kg/m³ and must flow at 0.75 m³/s The irreversible losses in the system equate to 12 m of head. Assume that the water is discharged at the deck of the rig that is 30  meters above sea level. How many kilowatts of power must be applied to the pump shaft?

Answer 1

+ head loss Net head supplied. by pump 7 H = height of Rig =) H=30+12 9 M = 42 m. g: 0.75 m2 13 Pa 10.30 *9/m9 g - 9.81 m182 7 power delivered = Pow = 199H to water 5) Pw = 10 30 90.75 x 9.81042 Pw = 318.285 KW But n pump Pawer delivered to water; Pw Power applied to pump shaft, P 918.2.95 P -) 0.9 = Pws P -) P= 397.857 kW Scanned with eamScanner