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Differents results between OPF2.1.2 and OPF2.30

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Old   March 16, 2015, 06:29
Default Differents results between OPF2.1.2 and OPF2.30
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ynos
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Hi Foamers
I have got differents results when I run the same model with OP211 and OP230, the only one file that I change is fvSchemes.

OPF211
divSchemes
{
default none;
div(phi,U) Gauss linearUpwindV grad(U);
div(phi,k) Gauss upwind;
div(phi,omega) Gauss upwind;
div((nuEff*dev(T(grad(U))))) Gauss linear;
}

OPF230
divSchemes
{
default none;
div(phi,U) bounded Gauss linearUpwindV grad(U);
div(phi,k) bounded Gauss upwind;
div(phi,omega) bounded Gauss upwind;
div((nuEff*dev(T(grad(U))))) Gauss linear;
}

Can anyone help me?
Thanks in advanced
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Old   March 16, 2015, 06:58
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Alexey Matveichev
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Hi,

If you really like to get an answer it is better not to increase the number of posts with the same content but

1. Provide more detail on your case (from "bounded" keyword addition I can conclude that you are using steady state solver, but that is all I know about your case and it is not enough).

2. Explain real meaning of "I have got differents results".
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Old   March 16, 2015, 07:35
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Hi there
I meshed a geometry with OPF2.3.0. And then run this mesh with OPF2.1.1 and 2.3.0. Everyfiles are the same except the fvSchemes, you can see the diferences down.
I get different results in the integration of forces ,on the order of 10%


OPF211
divSchemes
{
default none;
div(phi,U) Gauss linearUpwindV grad(U);
div(phi,k) Gauss upwind;
div(phi,omega) Gauss upwind;
div((nuEff*dev(T(grad(U))))) Gauss linear;
}

OPF230
divSchemes
{
default none;
div(phi,U) bounded Gauss linearUpwindV grad(U);
div(phi,k) bounded Gauss upwind;
div(phi,omega) bounded Gauss upwind;
div((nuEff*dev(T(grad(U))))) Gauss linear;
}

Can anyone help me?
Thanks in advanced
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Old   March 16, 2015, 16:06
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I did the same test with streambody , with 0 angle of atack and i got 7.3 % diference in pressure drag between 2.1.1 and 2.3.1 versions. Same Mesh, same fvsolution , fvschemes .... just adding bounded in 2.3.1 for divSchemes.

Coments are welcome.
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Old   March 17, 2015, 07:06
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Pablo Higuera
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I guess Henry Weller pointed out this "not-an-issue" thing in my bug report that you can find here:

interFoam pressure miscalculation in 2.3 (wrt previous versions)
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Old   March 17, 2015, 09:00
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Following the code linearUpwindV.C, has changes between 2.1.x and 2.3.x, i will back to the old version and recompile, i will inform if it is improving.
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Old   March 18, 2015, 15:47
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Still similar diferences, lastest times i meshed with 2.3.x and run with 2.1.1. I decided to move run to the 2.3.x also, but results are too diferents.

Really, i can not understand if other user and developers never got same problems.

At the end editing linearupwindV.C and coment lines from 137 to 216 (both included), i got really similar results. Of course you must recompile the obj.

Last edited by pablodecastillo; March 19, 2015 at 14:07.
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