Water flows uniformly 1.9 m deep in a rectangular grass-lined earth channel 5.5 m wide (Manning n = 0.03). The bed drops 2 m per kilometre. Use Manning’s equation in SI units to find the mean velocity V.
Water flows uniformly 0.4 m deep in a rectangular clean earth channel 5 m wide (Manning n = 0.022). The bed drops 4 m per kilometre. Use Manning’s equation in SI units to find the mean velocity V.
A trapezoidal clean earth channel has a bottom width of 1.5 m and side slopes of 1:1 (horizontal:vertical). Water flows uniformly 0.6 m deep. Manning n = 0.022 and the bed slope is S = 0.001. Find the flow rate Q in m³/s.
A concrete storm sewer with an inside diameter of 600 mm flows just full (as an open channel, not under pressure). Manning n = 0.013 and the slope is S = 0.005. Find the flow rate Q in m³/s.
A concrete sewer with an inside diameter of 250 mm (Manning n = 0.013) must reach a self-cleansing velocity of 0.9 m/s when flowing just full. Find the minimum slope S (in m/m).
A concrete sewer with an inside diameter of 375 mm (Manning n = 0.013) must reach a self-cleansing velocity of 1 m/s when flowing just full. Find the minimum slope S (in m/m).
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