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Old 11-05-2011, 03:13 PM   #189 (permalink)
aerohead
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2-D vs 3-D?

Quote:
Originally Posted by KamperBob View Post
I played around with Flow Illustrator. I can't figure out if I'm using it wrong or if it is really inaccurate. Here is a 256x128 mask of Phil's template.



The flow field is not hugging curvature at all. The tail is shedding a KV street.



Re = 2500000 (2.5e6)
dt = 0.1 (0.01 wasn't working)
length = 40s
cutoff = 10 (40 wasn't working)

Can anyone tweak FI to validate this case?
I think the program is treating the 3-D,2.5:1 'Template' streamline body of revolution as a 2-D streamline section.I don't have Marchaj's table with me but memory( what a joke!) tells me that for best 2-D flow you need 3.92:1 streamline section.That should kill the Karman vortex street your seeing behind the 'Template.'
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