A scale model of a pump has been tested and the following results obtained. Impeller diameter (D)           110mm Power input (P)                   2.5kW  Speed (N)                           1500 r.p.m. Flow (Q

For a 6.25-inch Model 4075 pump operated at 1160 rpm, if 450 GPM of water is to be delivered, what will be the estimated pump head in ft? HEAD IN FEET 30 25 0 0 0 10 O 6 ft 7.25" (184mm) 20 7.00" (178mm). 6.75" (171mm). 6.50" (165mm)] 15 6.25" (159mm). 5 O 16 ft O 20 ft O 12 ft aco® L/SEC 5 OT 10 Model 4075 FI & CI Series 15 -6-6 ⁰ dº 20 ANA 888 778 25 REQUIRED NPSH do 1160 RPM November 1, 2010 K ・dº- [M 90 do 30 8800 81 1HP(.75KW) DeJ kin do 60% 35 do 50 Curve no. 2175 Min. Imp. Dia. 6.25" Size 5 x 4 x 7.0 40 45 3HP(2.2KW), 2HP(1 5KW) 5HP(1 1KW)> CURVES BASED ON CLEAR WATER WITH SPECIFIC GRAVITY OF 1.0 L 75 150 225 300 375 450 525 600 675 FLOW IN GALLONS PER MINUTE NOWONG FEET 15 12 7 6 2 1 NPSH 758 50 5 HEAD IN METERS 45 586888 KPO 60 40 20 10 LO HEAD IN KILOPASCALS

A Pitot-static probe was used to measure the velocity distribution in a water tunnel. The two pressure lines from the probe were connected to a U-tube manometer which uses a liquid of specific gravity 1.7. The maximum velocity expected in the water tunnel was 2.3 m/s. Your job was to select an appropriate U-tube from a manufacturer which supplies manometers of different heights. The cost increases significantly with manometer height. Which of these should you purchase?

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