Answer Happy

4. A 6m wide 1 in 10 sloping channel enters a reservoir with a higher water level at a discharge rate of 35m3/s. The depth at the end of the channel is assumed to be a constant value of 4.755m as dictated by the water surface level in the reservoir. The spillway is long enough for the flow to become established at the normal depth before it encounters the backwater from the reservoir at which point a hydraulic jump occurs as shown. The upstream depth of the jump is equal to the normal depth of the channel. Take n = 0.017 s/my D DN Horizontal Reservoir 4.755m Di Jump Length a. Calculate the control points in the channel and hence classify the backwater curve occurring just after the jump. b. Using the direct step method with 4 intervals determine the elevation of the water surface profile between the entrance to the reservoir where y = 4.755m and the end of the hydraulic jump i.e. D2. You do not need to sketch the profile. c. How far upstream from the start of the reservoir does the hydraulic jump end.