CIV E 530 - OPEN-CHANNEL HYDRAULICS
SPRING 2008
HOMEWORK No. 8


  1. A diversion dam of height H = 2.5 m is planned on a steep stream with bottom slope So = 0.015. A hydraulic jump is expected upstream of the dam. Identify the type of water surface profile. Using ONLINE CALC, calculate the length of the water surface profile, from the diversion dam to the [downstream end of the] hydraulic jump. The channel has Q = 5 m3/s, bottom width b = 6 m, side slope z = 2, and Manning's n = 0.025. What are the sequent depths?

  2. A mild channel enters into a steep channel of slope So = 0.03. Identify the type of water surface profile in the steep channel. Using ONLINE CALC, calculate the normal depth in the steep channel, and the length of the water surface profile to within 1% of normal depth. The channel has Q = 3 m3/s, bottom width b = 5 m, side slope z = 0, and Manning's n = 0.015. What is the normal-depth Froude number in the steep channel?

  3. A steep channel of slope So = 0.04 enters into a milder steep channel of slope So = 0.01. Identify the type of water surface profile in the milder steep channel. Using ONLINE CALC, calculate the normal depth in the downstream channel, and the length [to normal depth] of the water surface profile. The channel has Q = 2 m3/s, bottom width b = 6 m, side slope z = 1, and Manning's n = 0.015. What are the normal-depth Froude numbers? What would be the length of the water surface profile if Manning's n was instead estimated at 0.013?