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July 26, 2010, 06:17 |
symmetric flow
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#1 |
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Hi all friends! I simulated model 3D in symmetric flow and computed onehalf of flow. after iterations, I want to compute force(lift and drag) of model. But their values to small (half) in comparison with experiment's values.
Please tell me how to do! Thank you for reading! (sorry for my english) Last edited by lehoang_mai; July 26, 2010 at 16:33. |
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July 27, 2010, 02:12 |
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#2 |
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Maxime Perelli
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You are computing one half of your model, and you are getting one half of expected result.........
Fluent doesn't multiply automatically the results for reaching the total result (ie: without symmetry). I mean it returned you the results for the computed domain (one half)
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July 27, 2010, 05:30 |
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#3 |
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Thank -mAx- very much!
You're right, it returned me the results for one half of domain. But I viewed results in field flow (pressure, velocity....), they're same as in field flow of full domain. Do you know, how to calculate lift anf drag in symmetric situation in order that It returned me same results in full domain? |
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July 27, 2010, 06:34 |
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#4 |
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Maxime Perelli
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If you are computing one half of geometry, the pressure and velocity won't be multiply by 2 for the full domain.
it is a question of section. For instance the pressure force on a body will be multiply by 2 for the full domain since the surface is double (projected forces normal to symmetry don't have to be multplied by 2, since they will be compensated). To your question, then you need to give the right Area in the reference values.
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July 27, 2010, 07:27 |
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#5 |
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Thanks you for reply!
And more little question from me. If I will compute one half of geometry, then the pressure force (and total force) on a body will be multiply by 2 for the full domain, isn't it? |
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July 27, 2010, 07:45 |
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#6 |
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Maxime Perelli
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yes, but not in the normal direction to your symmetry (here it should be 0)
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July 27, 2010, 07:56 |
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#7 |
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Thanks you very much!
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