Dismiss Notice
Join Physics Forums Today!
The friendliest, high quality science and math community on the planet! Everyone who loves science is here!

Homework Help: Open Channel Flow (mannings equation) rectangular section

  1. Sep 23, 2008 #1
    A rectangular concrete-lined channel is 2m wide with Manning's n 0.012 and a bed slope of 0.0025 m/m. Obtain the depth of flow when the discharge is 9m^3/s.

    Q=V.A I have the discharge but how do I calculate the velocity without the area ?? Once I have the velocity I should be able to work it out.

  2. jcsd
  3. Sep 23, 2008 #2
    You've got two equations with two unknowns: eliminate v. Write the area A as b*h with b the width and h the height of the rectangular cross-section. Now solve for h.
    Last edited: Sep 23, 2008
Share this great discussion with others via Reddit, Google+, Twitter, or Facebook