17. A self-priming centrifugal pump is used to pump water at 25°C from a reservoir whose surface is 2.5 m below the centreline of the pump inlet (see figure below). The pipe is PVC pipe with an internal diameter of 25 mm and negligible average inner roughness height. The pipe length from the submerged pipe inlet to the pump inlet is 3.1 m. There are only two minor losses in the piping system from the pipe inlet to the pump inlet: a sharp-edged re-entrant inlet (KL = 0.85), and a flanged smooth 90° regular elbow (K₁ = 0.30). The pump's required net positive suction head is provided by the manufacturer as a curve fit: NPSHrequired = 2.5 m + [0.0015 m/(Lpm)²] V/², where volume flow rate is in Lpm. Determine the following: a) The maximum volume flow rate (in units of Lpm) that can be pumped without cavitation. Hint: compare available NPSH and required NPSH. 22-21 Reservoir Pump

17. A self-priming centrifugal pump is used to pump water at 25°C from a reservoir whose surface is 2.5 m below the centreline of the pump inlet (see figure below). The pipe is PVC pipe with an internal diameter of 25 mm and negligible average inner roughness height. The pipe length from the submerged pipe inlet to the pump inlet is 3.1 m. There are only two minor losses in the piping system from the pipe inlet to the pump inlet: a sharp-edged re-entrant inlet (KL = 0.85), and a flanged smooth 90° regular elbow (K₁ = 0.30). The pump's required net positive suction head is provided by the manufacturer as a curve fit: NPSHrequired = 2.5 m + [0.0015 m/(Lpm)²] V/², where volume flow rate is in Lpm. Determine the following: a) The maximum volume flow rate (in units of Lpm) that can be pumped without cavitation. Hint: compare available NPSH and required NPSH. 22-21 Reservoir Pump

Elements Of Electromagnetics

7th Edition

ISBN:9780190698614

Author:Sadiku, Matthew N. O.

Publisher:Sadiku, Matthew N. O.

ChapterMA: Math Assessment

Section: Chapter Questions

Problem 1.1MA

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