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[ANSYS Meshing] Results getting worse with Refinement

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Old   June 20, 2015, 15:04
Default Results getting worse with Refinement
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Tiago Fonseca Costa
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Hello,

I'm simulating a drag on a sphere with Re = 10.000. In the internet, my references for a acceptable value for it's drag coefficient are from 0.39 to 0.47. I tried a simulation with a 1m radius sphere on a 20m uniform box enclosure. I'm using SST as a turbulence model and I'm getting pretty good results without any kind of Mesh Refinement (the Drag Coeff. calculated was 0.484, pretty close to the acceptable values). But when I add Refinement to the surface of my sphere (on the fluid side), all the three types of it (Refinement level 1, 2 and 3), my results just go to something like 0.19, 0.20 (and I expected them to go to a range of 0.40, 0.45 or something inside the acceptable range). Does anyone have an idea of what's going on?

Tiago.

(P.S.: sorry for bad English, not my native language!)
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Old   June 23, 2015, 22:44
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Do you have an inflation layer?
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