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Old 01-29-2011, 10:12 AM   #183 (permalink)
ChazInMT
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Your RE is off the chart, Dr C himself sez to use between 100 & 1000. Here is a copied quote from the "More Info" tab on his website.

"Very crudely, for bluff bodies (like cars, or any body the flow past which is separated) effective Re, if based on the body largest cross-section dimension, is usually between 100 and 1000. Note that the laminar, numerical, and turbulent viscosities differ not only in magnitude but in many other respects, so that one can never be accurately modelled by the other."

So Re set to 2.5 million is a bit outside this.

Also, I have noticed a huge difference in how shapes perform in "free air" and "ground effect". The ideal template in free air acts quite different than when close to the ground.

Also keep in mind, this flow illustrator is just kind of a toy, it is very difficult to set it up accurately to use as an actual predictor of real world flow depiction.

I set Dt=.2 it simply speeds things up a bit, and time of more than 15 Sec does not accomplish much.

Hope this helps. Don't forget to check out the "More Info" tab on the Flow Illustrator site.
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