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Old 05-19-2010, 06:17 PM   #8
vex
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Quote:
Originally Posted by infernosg View Post
Yes, but this

is not correct. Turbulent flow != higher velocity but rather, more energy. Laminar flow is typically considered to be uniaxial whereas turbulent is not, so in the direction of your flowlines laminar flows will always have the greater velocity. Due to its higher energy a turbulent boundary layer is smaller and more stable than a laminar boundary layer so it will adhere to the surface better (think golf balls).

To the OP, smoothing out the transitions is good, but for finish you don't want a mirror finish, nor do you want something resembling sandpaper in there. Too smooth and your flow area will actually decrease (due to large laminar boundary layers) and hurt flow into the engine. Conversely, too coarse will result in excessive friction, which will slow down flow significantly despite utilizing the entire flow area.
I should have paid more attention in Aero/Hydro.

I thought the purpose of the rougher surface (and similarly vorticity generators) was to trip the boundary layer inducing a turbulent flow? Maybe I'm confusing terms/physics here? Clarify?

Oh wait, I see my mistake. LOL, what a stupid thing to say!

Last edited by vex; 05-19-2010 at 06:31 PM.
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