- (20%) A steep rectangular channel with So = 0.015 changes abruptly to
another rectangular channel of slope So = 0.004 and of the
same width. The friction factor (1/8 of Darcy-Weisbach) in both channels is f= 0.004.
The discharge is q = 20 cfs ft-1.
What is the length of the resulting C3 profile on the downstream channel?
- (20%) A hydraulically wide channel is operating at Froude number F = 0.25. The unit-width discharge is q = 3 m2s-1.
What is Lagrange's relative celerity? What are two Langrange absolute celerities (usptream and downstream)?
- (20%) You are observing the rising flood stage of a major river.
At your observation point, at a certain time the discharge is
300 m3 s-1, and the stage is rising at the rate of 8 mm hr-1.
The surface width of the river at this point, and for several kilometers
upstream, is 105 m. What is your quick estimate of the present discharge
at a point located 10 km upstream of your observation point?
- (20%) Please answer each question in one clear and concise paragraph:
- What is the rationale for the labyrinth spillway? When does it cease to work as intended?
- Compare kinematic, diffusion, and dynamic waves in terms of their celerities and diffusivities.
- At what Froude and Vedernikov numbers do kinematic, diffusion and dynamic wave coalesce?
- What is the difference between the Schaake and Li methods to solve the kinematic wave equation?
Which method is more stable? Which method is more accurate?
- (20%) Write a 300-word essay either (a) defending or (b) attacking the Muskingum-Cunge method. Please consider content, grammar, and spelling.
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