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CE 230-Engineering Fluid Mechanics. Lecture # 33-34 Noncircular conduits Uniform flow in open channels. If the conduit is not circular then we should do the following. Replace D in head loss formula by 4A/P=4Rh Relative roughness = ks/4Rh Re=V(4Rh)/ ν Then continue as before.
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CE 230-Engineering Fluid Mechanics Lecture # 33-34 Noncircular conduits Uniform flow in open channels
If the conduit is not circular then we should do the following Replace D in head loss formula by 4A/P=4Rh Relative roughness = ks/4Rh Re=V(4Rh)/ν Then continue as before
Uniform flow in open channels • For this flow the deriving force is gravity which means that the channel has to be sloping in the flow direction • An empirical equation is used to analyze this type of flow which is called the MANNING EQUATION
terminology A area P wetted perimeter Hydraulic radius = A/P Manning Equation SI units B. units
10.128 Find average velocity in the shown concrete lined channel if the Slope is 1 ft in 2000 ft. The depth of flow is 6 ft.
Example 10.21 “modified” Determine Q if D= 5 ft, slope =0.001, flow depth = 4 ft Concrete sewer