The discussion centers on the feasibility of achieving laminar flow in a rectangular cross-section tube measuring 1 cm by 5 cm, with air velocities between 100 to 150 m/sec. The initial Reynolds number calculation was incorrectly estimated at 7000 but was later corrected to approximately 260,000, indicating that sustained laminar flow is unlikely. Participants agree that while laminar flow may occur over a short distance near the entrance of the tube, turbulence will dominate over longer distances, making it impractical to maintain laminar flow over 20 cm.
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What is your assessment of this so far?Swamp Thing said:Is it possible to create (nearly?) laminar flow in a tube with rectangular C.S. , around 1 cm X 5 cm , with air moving at around 100 to 150 m/sec?
Turbulence will likely set in sooner or later, but can the laminar flow be made to last over say 20 cm?
I agree.Swamp Thing said:When I posted, I had got a Reynolds number around 7000. So I was wondering if it would work if we used a sheaf of soda straws or something to laminarize the flow.
But I have since found errors in my calculation -- the RN is actually like 260,000. So it's probably not doable, I'm thinking.