CIV E 530 - OPEN-CHANNEL HYDRAULICS

SPRING 2018 - MIDTERM 2 - SOLUTION

PROBLEM 3: ESSAY QUESTIONS

1.

    In the Manning equation, the power of hydraulics radius is 2.3; in the Chezy equation it is 1/2.
    Manning equation is dimensional; Chezy equation can be expressed in dimensionless form.
    Manning n does not vary with the units; Chezy C does vary with the units.
    Manning is practical; Chezy is theoretical.

2.

    The brute force method is direct; Newton's iteration is iterative.
    Brute force method advances with the trial value; Newton's iteration uses the tangent, once the trial value is near the root.
3.
    The are twelve (12) types of water-surface profiles in gradually varied flow. The profiles C1 and C3 are completely horizontal.

4.

    So (gravity), Sc (friction), and Froude number (hydraulics).

5.

    When the water is clear of sediment, there is more erosion of the boundary, because the permissible shear stress decreases, making the water more hungry for sediment.
Problem 4

 
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