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

Triangular duct flow

  1. Dec 11, 2005 #1
    Dear friends,

    Does anybody now how I derive the equation that describes the flow in a triangular duct.
    making the assumptions
    constant properties
    no slip at walls

  2. jcsd
  3. Dec 11, 2005 #2


    User Avatar
    Science Advisor
    Gold Member

    The equation you shl

    Neglect unsteady term of N-S equations: [tex]0=-\nabla P +\mu\nabla^2\overline{u}[/tex]. This is the equation for viscous and incompressible flow. The main problem you have is to establish a coordinate system. Solving this problem in cylindrical or cartesian coordinates may be a little bit difficult. A nice engineering approach is to calculate the Hydraulic Diameter of the pipe (which holds [tex]\dot {m}=\rho UA[ /tex] assuming a round pipe), and work in cylindrical coordinates with that average diameter.
  4. Jan 11, 2006 #3
    Thank you Claussius,

    That is a possibility however, I know there is a closed form analytical solution to this problem the initial N-S equation is correct but the boundary conditions are not so easely defined.

Share this great discussion with others via Reddit, Google+, Twitter, or Facebook