An impeller of a centrifugal pump runs at 90 rpm under a net head of 10 m and has vanes inclined at 120° to the direction of motion at outlet. The diameter of impeller at exit is double than that at inlet and velocity of flow is constant at 2.5 m/s. The manometric efficiency is 75 %. Find (a) diameter of impeller at exit and (b) Vane angle at inlet.

An impeller of a centrifugal pump runs at 90 rpm under a net head of 10 m and has vanes inclined at 120° to the direction of motion at outlet. The diameter of impeller at exit is double than that at inlet and velocity of flow is constant at 2.5 m/s. The manometric efficiency is 75 %. Find (a) diameter of impeller at exit and (b) Vane angle at inlet.

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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A single-stage centrifugal pump having a suction pipe 254 mm in diameter anda discharge pipe diameter of 5 inches is being tested and found out to discharge 48 lps ofwater. A pressure gage connected to the inlet pipe reads 118 mm Hg vacuum and adischarge gage reads 150 kPa at a distance 100 cm above the point where the inletpressure was measured. If the kW rating of the driving motor is 12 kW, calculate: a) the pump efficiency. b) if this pump runs at 1800 rpm, what will be the new discharge rate,head, and power developed if the pump speed was increased to 3600 rpm? Assumeconstant efficiency. c) Determine the pump type.
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