E4.8 Pressure Drop in Liquid Flow

Example 4.8: Water flows through a pipe having inside diameter 0.5 in at 7.25 ft/s. The pipe is 100 ft long. Determine the pressure drop if the pipe is made of (a) drawn brass tubing, (b) drawn lead tubing, (c) drawn glass tubing, (d) commercial steel, (e) wrought iron, (f) asphalted cast iron, (g) galvanized iron, (h) cast iron, (i) concrete, or (j) riveted steel. Use the following information:

Density of water = 62.37 lb/ft³, viscosity of water = 1.12 cP

Solution:

Inside diameter of the pipe, d = 0.0417 ft.

Viscosity of water, μ = 7.526 ´ 10^-4 lb/(ft·s).

Reynolds number Re (Equation 4.14):

Note that the materials of construction of the pipes are different for each case.

Roughness of the pipes (Table 4.1):

Friction factor, f (Figure 4.3):

Frictional losses, h_fs (Equation 4.11):

Pressure drop, ΔP:

Results are presented below: