In a laboratory experiment involving flow of water (density =
990 kg/m3 and viscosity = 0.001 Pa-s) in a pipe network comprised
of a sudden enlargement from 12 mm diameter pipe to 20 mm diameter
pipe followed by a sudden contraction back to the 12mm pipe and a
90o bend as shown in Fig. 3. For a flow rate of 10 L/min and the
given dimensions, and the measured head loss of -12 mm for the
sudden expansion (A-B) and 52 mm for the sudden contraction (C-D),
determine (a) the head loss coefficient for the sudden expansion
and the sudden contraction, (b) the friction head loss for the 20
mm diameter straight pipe assuming a roughness of 0.3 mm and a
length of 1500 mm between points B and C, and (c) the head loss for
the 90o bend (D-E) for a total pipe length of 1200 mm, a total head
loss of 650 mm and a friction coefficient of 0.056 between points D
and F.