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Reverse flow on a Presure outlet

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Old   March 26, 2010, 20:37
Default Reverse flow on a Presure outlet
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alberto
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Hey guys
I'm teying to run a simulation of a wing and i made a growth function mesh on it, when i go to fluent there is a msg of a reverse flow on the pressure outlet face. Can some one tell me how to simulate it or how could i mesh the wing in order to get the best results.?
P.S. I'm using Gambit to mesh it.
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Old   March 27, 2010, 05:25
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There is a good tutorial of an airfoil.
Well, it's not a wing, but you will get a good overview whats important so such an external flow.
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Old   March 27, 2010, 07:11
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Hi
it is not a problem if u get a reversed flow....
Tell us more about ure outlet position: is it enough far from the wing???? do u have any vortex schedding???
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Old   March 27, 2010, 12:06
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Well the outlet is far enough i think, the thing is that the results that are coming out are not good at all... is good to tell you guys this is a 3D wing.

p.s. thanx for your help.
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Old   March 29, 2010, 03:49
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well, i dont think the problem is the reverse flow on the pressure outlet ...

are u using steady or unsteady solver?????? wich turbulence model????? wich near wall treatment ?did u verify convergence???? do u have vortex schedding ???? what do u got as results?
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Old   March 29, 2010, 18:58
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Well I'm using a Pressure Based, steady flow solver, I changed the operating conditions turn on the spalart allmaras viscuos model, and i also changed my convergence to 1E-6.
And my results are negative lift negative drag and a moment that is really out of order... if you have any idea of how I can improove my simulating Ill be realy thankfull.

PS. I changed the reference values the area and the temp.
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Old   April 1, 2010, 18:09
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ure residuals have gone under 10-6????
if yes, i suggest that u use unsteady solver and that u average results then.
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Old   April 2, 2010, 08:54
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do u have any problem by the reverse flow?
do u have any divergence in residuals?
if u have not any problem by above-mentioned please go on and don't wait.
in the end boundary u may have some real reverse flow and tiny circulation zone. have u?
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