Question 2

Water flows at 1.6 m³ s¹ through a long rectangular drain of width 0.8 m and streamwise slope 1.25%.

Manning's roughness coefficient may be taken as n = 0.013 m-1/3 s.

(a) Find the depth of flow in the drain.

At one point the drain opens out abruptly into a broader channel of width 2.2 m and lower slope, causing an

immediate hydraulic jump.

(b) Estimate the depth of flow and Froude number just downstream of the hydraulic jump.