Question

(100 points) Water at 25°C is pumped at a rate of 0.075m's from a reservoir 20m above a pump to a free 1. discharge (this means discharged to atmosphere) 35m above the pump. The pressure on the intake side of the pump is 150kPa and the pressure on the discharge side of the pump is 450kPa. The pipe between the reservoir and the pump is 3 meters of Sin diameter cast iron. From the pump to the discharge the pipe is 50m of 25cm commercial steel. Each elbow is a regular flanged elbow. a. Determine the head supplied by the pump b. Total head loss between the pump and the discharge C. If operating at 1750rpm. Calculate the specific speed and state what type of pump should be used d. Select a pump from the provided curves e. Provide the bhp and efficiency of the pump f. Is the pump in danger of cavitation? Justify your answer D- 15 cm Free discharge 435 m Elbows are flanged ·20m Pa 450 kPa P2=150kPa Equivalent Roughness for New Pipes [From Moody (Ref. 7) and Colebrook (Ref. 8)] Equivalent Roughness, ε Pipe Feet Millimeters Riveted steel 0.003-0.03 0.9-9.0 0.3-3.0 Concrete 0.001-0.01 0.18-0.9 Wood stave 0.0006-0.003 0.26 0.00085 Cast iron 0.15 0.0005 Galvanized iron Commercial steel 0.045 0.00015 or wrought iron Drawn tubing Plastic, glass 0.0015 0.000005 0.0 (smooth) 0.0 (smooth) Loss Coefficients for Pipe Components (m =KL)Data from, Refs 5, 10 Coefficients for Pipe Components (Data from Refs. 5, 10, 27) 2g Component KL a. Elbows Regular 90°, flanged Regular 90, threaded Long radius 90°, flanged Long radius 90, threaded Long radius 45°, flanged Regular 450, threaded 0.3 1.5 0.2 0.7 0.2 0.4 b. 180° return bends 180° return bend, flanged 180° return bend, threaded 0.2 1.5 c. Tees 0.2 Line flow, flanged Line flow, threaded 0.9 1.0 Branch flow, flanged Branch flow, threaded 2.0 0.08 d. Union, threaded e.Valves 10 Globe, fully open Angle, fully open Gate, fully open Gate. closed Gate, closed Gate, closed Swing check. forward flow Swing check, backward flow Ball valve, fully open Ball valve, closed Ball valve, closed 0.15 0.26 2.1 17 o0 0.05 5.5 210 See Fig. 8.32 for tvnical yalve ecometry 1785 rpm 1920 26 AXIAL FLOW 10" PO ONI MWI 1600 rpm 71% 1400 18 16 14 200 m 12 ー10 40 20 3500 3000 2000 1500 1000 500 Water Flow 09 0 0.13 0.15 017 Water Flow (m/s) 021 0.03 005 Model 4011 FI&CI Series aco 1760 RPM Curve na. 2286s 51 .. 11.0 1,2010 Se Nombor 1.2010 200 FTTTR 75 15 4 to F3 160 40 [400 0(267mm 120 500 50 80 2o g f200 40 10 100 CURVES BASED ON CLEAR WATER WTH SPECIFIC GRAVITY OF 1 0 0 0 0200 400 600800 1000 1200 1400 1600 FLOW IN GALLONS PER MINUTE 75 0MIXED FLOW 21 MWI 16" 1480 rp 20 65 19 PUMPS 60 17 1300 16 so 150 rpm 1240 11 t= 35 10 20 15 50 bp 10 30 10 2000 3000 400 000 6000 7000 8000 9000 10000 11000 Water Flow (gpm) 0.15 0.20 0.25 030 0.35 040 0.45 0.50 0.55 0.60 0.65 Water Flow (m/s)

Answer 1

head supplied s (950150 xoo ニ65m velocity ご 0.OT5 ahea 수 (0.25) head loss Lt. 2 1 0-103 +33-f 2.3.2. Speedie Spee ber 3 w be best