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Old 01-26-2020, 09:11 PM   #4 (permalink)
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Originally Posted by stefaantje View Post
Hi Vman, my 30 mph and 60 mph were just some random figures, just for some scale in my comparison.
I was comparing ideal teardrops / raindrops. Those do get laminar flow, don't they?
It all depends on Reynolds number (Re), which is the ratio of inertial force to viscous force of the fluid. At sub-critical Re, flow is laminar; above sub-critical Re, flow is turbulent. Shape doesn't come into that; it's purely a function of fluid viscosity, fluid velocity, and test length.

You're probably thinking of attached versus unattached flow, a common mistake. Yes, an ideal teardrop should have attached flow at the speeds we talk about here.

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