Handbook of Civil Engineering Calculations

Diameter of circular, or side of square, pipe

FIGURE 8. Flow of water in pipes. (From E, W. Schoder and F. M.

Dawson, Hydraulics, McGraw-Hill Book Company, New York,

1934. By permission of the publishers.)

Extremely rough pipes:

O.69LV^2

hp

~ ioooD

125 (2ld)

Using Eq. 216 gives V= QIA = 3/0.349 = 8.60 ft/s (262.128 cm/s); hF = 0.38(2.6)

(8.60)L86/0.667L25 - 89.7 ft (27.34 m).

2. Alternatively, determine hF using Eq. 20
   First obtain the appropriate/value from Fig. 8, or/= 0.020 for this pipe. Then hF =
   0.020(2.600/0.667)(8.60^2 /64.4) = 89.6 ft (27.31 m).


3. Compute the pressure at the pump discharge
   Use Eq. 9. Since LID > 500, ignore the secondary items. Then/Vw = Z 2 + hF = 180 + 89.6
   = 269.6 ft (82.17 Tn) 9 P 1 = 269.6(62.4)7144 =117 lb/in^2 (806.7 kPa).

Millimeters Meters-

Diameter of circular, or side of square, pipe

Inches Feet