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 = 0.14. 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 = 1.2 m² s^-1. The energy loss is ΔE = 2.4 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 75 mm hr^-1. The surface width of the river at this point, and for several kilometers upstream, is 85 m. What is your quick estimate of the present discharge at a point located 7.2 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?

   • Why can't the Saint Venant equations be solved in closed form? What is the solution that is used in practice?

   • What are the three forms of the Seddon celerity? When did Seddon write his paper?

   • What is the range of rating exponent (beta) likely to be encountered in actual practice?

   • Which version of HEC-RAS is steady only? Which version of HEC-RAS has steady and unsteady features?

   • What type of unsteady flow wave (kinematic, diffusion, dynamic) is the most diffusive?

   • Which scheme to solve the kinematic wave equation (1. backward-in-time/forward-in-space; 2. centered in-time-and-space; 3. backward-in-time/backward-in-space) is the most diffusive? Why?

   • What is the cell Reynolds number? Where is it used?