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Unread 08-01-2014, 16:12
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Re: Ball Flight Model

Quote:
Originally Posted by NotInControl View Post
I have developed my own model which only accounts for air resistance, I currently ignore spin because I don't think we will be adding spin to our ball.

But I pluged your numbers into my model: using your launch angle of 60 degrees and inital velocity of 22ft/s the results seem very comparable. Note: I DID NOT change my air density of 1.2 kg/m^3, mass of 1.2474kg or Cd which is 0.47 to yours so that is why the number differ slightly.

But here are my results. The Green line represents the center of the top goal, and the red line represents the white zone.

Note again this is only with air drag, not spin.

Remember this is only a simulation, and while our simulations may agree, I would urge you to do some data validation experiments, before you use the results of the simulation to drive your design.

Hope this helps,
Kevin
Thanks Kevin for the data, much appreciated!

I am still brushing up on my fluids (humbling exercise) and going through the U of Il theory. My thinking is that simple calcs (no drag) would provide a good enough estimate of velocity required to design shooter. I'm interested in aerodynamic effects for two reasons:
  1. Is there much benefit in back-spin for increasing apex height
  2. Will back-spin reduce any knuckle-ball effect? I.e., is there enough benefit to invest in more complex back-spin design?

For Rebound Rumble (Nerf basketball), backspin had a significant advantage for range and accuracy.