CIV E 530- OPEN CHANNEL HYDRAULICS
SPRING 2004
FINAL EXAM
MAY 12, 2004, 1530-1730

Name: ________________________ S.S. No. _________________ Grade: ____________

Instructions: Closed book, closed notes. Use engineering paper. When you are finished, staple your work in sequence (1 to 4), and return this sheet with your work.

  1. (20%) A hydraulically wide channel is operating at Froude number F = 0.12. The unit-width discharge is q = 2 m2s-1. What are two Langrange celerities?

  2. (20%) A hydraulic jump occurs in a rectangular channel with a design discharge of q = 1 m2 s-1. The energy loss is ΔE = 2 m. What are the initial and sequent depths?

  3. (20%) You are observing the rising flood stage of a major river. At your observation point, at a certain time the discharge is 250 m3 s-1, and the stage is rising at the rate of 55 mm hr-1. The surface width of the river at this point, and for several kilometers upstream, is 65 m. What is your quick estimate of the present discharge at a point located 6.2 km upstream of your observation point?

  4. (40%) Please answer each question in one clear and concise paragraph:

    • What is the range of Manning's n measured by USGS and published in Barnes' book and http://manningsn.sdsu.edu?

    • What is the exponent of the discharge-area rating under laminar flow conditions?

    • What is the difference between the Seddon and Lagrange celerities?

    • Under Chezy friction in hydraulically wide channels, what Froude number will cause roll waves to develop?

    • What is the principle behind the design of the labyrinth spillway?

    • What is the difference between kinematic, diffusion, and dynamic waves?

    • Other things being equal, which channel diffuses more: a steep or a mild? A narrow or a wide? Why?

    • What was Cunge's major contribution to unsteady open-channel hydraulics?