03-21-2010, 02:54 PM
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#51 (permalink)
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03-21-2010, 02:58 PM
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#52 (permalink)
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Master EcoModder
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Can anybody tell me if the NASA TetrUSS is usable for cars -- i.e. can it have a ground plane that is part of the "flow space" and not part of the model being tested?
TetrUSS: NASA Tetrahedral Unstructured Software System
It does have a Mac version, though I'm unclear about how to use the model I have made in it, to test for drag.
If not, how can I test my model in a CFD program? |
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03-21-2010, 05:19 PM
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#53 (permalink)
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EcoModding Apprentice
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You probably will want to round off the air dam area, since you have a belly pan.
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03-21-2010, 11:51 PM
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#54 (permalink)
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Master EcoModder
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Hi Bob,
You could be right -- I am hoping to test it (virtually) so I can find the trouble spots! I also want to be able to give it something "crisp" up front, and that area would function as a flush bumper.
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03-23-2010, 09:20 AM
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#55 (permalink)
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Master EcoModder
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I've smoothed out the front and sides; virtually rebuilding the entire model. Maybe it is ready for CFD testing?! I used far fewer polygons, to boot -- and obviously the side window looks a bit dorky; I need to work on it.
The standing figure is 5'-9" tall, FYI. Please note the slightly radius on the chin. |
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03-23-2010, 02:51 PM
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#56 (permalink)
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(:
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I'd say the guy's chin has a fairly normal radius!  |
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The Following 2 Users Say Thank You to Frank Lee For This Useful Post:
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03-24-2010, 12:35 AM
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#57 (permalink)
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Master EcoModder
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Late edits have strange logic...
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03-24-2010, 11:32 PM
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#58 (permalink)
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03-25-2010, 11:54 AM
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#59 (permalink)
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Master EcoModder
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Okay, I have the answer about importing my SketchUp model into Caedium for RANS flow -- it is not supported. 
The only common file type is the .OBJ and I was able to import it into Caedium: 
The fellow at that company whom I have been emailing said that a surface polygon model is not smooth enough; and in any case it is not supported... |
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03-25-2010, 10:34 PM
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#60 (permalink)
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Left Lane Ecodriver
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That's kind of funny, because the mesh that Caedium will generate is a (very high polygon count) surface polygon model.
Don't forget to call out accurate boundary conditions - wall below, far field above and to the sides.
I'll keep an eye on this thread, and I'll be thrilled if you can get better results from CFD than I did. If you get it working, you'll probably want to run many variants of the model through the simulation, and see how much drag certain design features add (test without the front wheel skirts, different ground clearances, etc).
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