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Unread 09-01-2012, 15:36
Ian Curtis Ian Curtis is offline
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Re: Drag coefficient of 2012 Game Piece

Quote:
Originally Posted by shuhao View Post
Is the viscosity calculation equally correct here?
I'm not sure what you're doing, but I'll readily admit my grasp on Boundary Layers isn't spectacular (one of those classes you can ride the curve to victory). Is that an assumed velocity profile? If it is I doubt it works, because the velocity profile varies with theta. Boundary Layers typically assumes small Re where you have nice laminar or creeping flow. Take a look at this .gif, on the backside the flow is going to seperate with a ball moving in air at any noticeable speed.

If it's one of those experimentally determined equations for Cd, then it is probably okay.
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