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How to modify oodles to print epsilon

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Old   December 9, 2008, 13:37
Default Hi Gijs, check that "create
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Ville Tossavainen
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Hi Gijs,

check that "createMyFields.H" is included after "createFields.H". Also check the equation for dissipation rate. It doesn't look like the right one...

Anyway, I have another solution. You can call "sgsModel->epsilon()" that computes TKE dissipation estimation (ce*ksgs*sqrt(ksgs)/delta for eddy viscosity models).

Hope this helps!
Ville
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Old   December 9, 2008, 14:30
Default Hi Ville, How are things? T
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Gijsbert Wierink
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Hi Ville,

How are things? Thanks for your reaction. I did put "#include createMyFields.H" after createFields.H. The equation is just a guess, because I also tried:



Info<< "Calculating the dissipation.\n" << endl;
volScalarField dissipation
(
IOobject
(
"dissipation",
runTime.timeName(),
mesh,
IOobject::MUST_READ,
IOobject::AUTO_WRITE
),
sgsModel->epsilon()
);



and that didn't work. Well, it does write out a file called "dissipation" every timestep, but it only contains the same info as the initial conditions (i.e. zerGradient for most things and some fixed values for the two inlets). Any idea how to fix that?

Thanks, Gijs
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Old   December 9, 2008, 15:54
Default Uups, you need to update epsil
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Ville Tossavainen
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Uups, you need to update epsilon somewhere in the code:

dissipation = sgsModel->epsilon();
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Old   December 10, 2008, 02:36
Default So you mean I should put "diss
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Gijsbert Wierink
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So you mean I should put "dissipation = sgsModel->epsilon();" in myoodles.C and have it also in createMyFields.H ?
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Old   December 10, 2008, 05:13
Default Hi Ville, Thanks for your h
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Gijsbert Wierink
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Hi Ville,

Thanks for your hint. To recap for others, this is what worked (at least for a few time steps, still need to test it for longer times):

Put in myoodles.C the lines "#include createMyFields.H" and "dissipation = sgsModel->epsilon()". Then, create a file called "createMyFields.H" (or whatever you like of course) with the code:

Info<< "Calculating the dissipation.\n" << endl;
volScalarField dissipation
(
IOobject
(
"dissipation",
runTime.timeName(),
mesh,
IOobject::MUST_READ,
IOobject::AUTO_WRITE
),
mesh
);

Now every writing step a file called "dissipation" is written that contains a field of subgrid epsilon.

Many thanks for your help Ville ( and also many thanks to Ville Vuorinen for helping me out)!

Cheers,

Gijs
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Old   December 10, 2008, 09:02
Default That's good to hear you got it
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Ville Tossavainen
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That's good to hear you got it working!
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