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Q9. A centrifugal pump runs at 600 rev/min and discharges sea water at the rate of 7 m³/min against a head of 14 m.

The impeller has an outer diameter of 500 mm and exit width of 30 mm.

The vanes are backward facing at an angle of 40 o from the impeller tangent.

There is no whirl at inlet and the thickness of the vanes may be ignored.

(a) Sketch the blade tip velocity vector diagram identifying the velocities. (4)

(b) Calculate EACH of the following:

(i) The radial velocity of the fluid; (2)

(ii) The whirl velocity at exit;(3)

(iii) The absolute velocity of the fluid at exit; (2)

(iv) The theoretical head; (3)

(v) The manometric efficiency. (2)