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Old 10-13-2012, 01:11 PM   #50 (permalink)
ConnClark
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Quote:
Originally Posted by Cd View Post
I managed to get the numbers pretty correct at a simulated .28, which had me really enthused, but the Cd varies so much each time you run the software you get a different number - actually it keeps going up and down as the software crunches the data.

What am i doing wrong ?
Your doing nothing wrong. In simulations you have vortices that form and shed. these give rise to the fluctuations. What you have to do is wait until the oscillations get relatively steady and average the value you are looking for through a few cycles.
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