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Old 06-03-2022, 09:48 AM   #9 (permalink)
Vekke
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Join Date: Jan 2009
Location: Kitee (Finland)
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At the moment clearly best drag came from AST II template 0,104

AST I Cd 0,114
AST II Cd 0,104
AST III Cd 0,113

Test 3d model is 500mm wide and all edges is rounded to 100mm

Cd values are not exact, but they are just comparable between each other the runs above. I ran the simulation at full resolution for 35 iterations. I am still learning so will get back to these results in the weekend. Migth be just that the mesh is still too small for the curvature.

The rear diffuser angle is same 11 degrees in all as AST III. Which is too steep IMO, on the AST II and AST I its 10 degrees. Ground clearance is also quite low like 82mm. Now its same on all is that ok or do I raise it to 140mm range or some other value?

I did run first tests with AST III model that was sitting at 100mm Then I got Cd 0,111 with 35 iterations so lowering helps... I also did one run to 130 iterations with that model that was 0,108 so drag values will get lower if you run it longer. Full run with that accuracy is over 6 hours of running. So I will put the machine running on nigth for final results for certain models.

Pictures of my simulations will come here
https://www.facebook.com/media/set/?...62635480416932
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Last edited by Vekke; 06-03-2022 at 04:55 PM..
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