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Unformatted text preview: ead loss if the pipe were smooth and the flow rate the
P6.60 J. Nikuradse in 1932 suggested that smooth-wall turbulent
pipe flow could be approximated by a power-law profile
uCL P6.62 P6.63 P6.64 1/N y
R where y is distance from the wall and N 6 to 9. Find the
best value of N which fits Laufer’s data in Prob. 6.57. Then
use your formula to estimate the pipe volume flow, and
compare with the measured value of 45 ft3/s.
A straight 10-cm commercial-steel pipe is 1 km long and
is laid on a constant slope of 5°. Water at 20°C flows downward, due to gravity only. Estimate the flow rate in m3/h.
What happens if the pipe length is 2 km?
The Moody chart, Fig. 6.13, is best for finding head loss
(or p) when Q, V, d, and L are known. It is awkward for
the second type of problem, finding Q when hf or p is
known (see Example 6.9). Prepare a modified Moody chart
whose abscissa is independent of Q and V, using /d as a
parameter, from which one can immediately read the ordinate to find (dimensionless)...
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This note was uploaded on 10/27/2009 for the course MAE 101a taught by Professor Sakar during the Spring '08 term at UCSD.
- Spring '08