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#1 |
Senior Member
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Dear everyone:
So far as I know, in dynamic smargrinsky model, the original way to calculated cD is unstable , so ensemble average is introduced to resovle the problem such as negetive value of cD. so you can find in http://foam.sourceforge.net/doc/Doxy...agorinsky.html : cD=<L.M>/<M.M>, which is intead of cD=L.M/M.M, where < > means ensemble average. But I don`t know what is the " average " in the source code ? it seems like that it is the "Arithmetic average:" for the field if that the cD is not the funtion of space.as original idea for dynamic model is to make the cD to be the function of time and space--cD=cD(x,t) so if anyone can tell me where is the code of the original function type for the average here in the code Thanks 00052 00053 dimensionedScalar dynSmagorinsky::cD(const volSymmTensorField& D) const 00054 { 00055 volSymmTensorField LL = dev(filter_(sqr(U())) - (sqr(filter_(U())))); 00056 00057 volSymmTensorField MM = 00058 sqr(delta())*(filter_(mag(D)*(D)) - 4*mag(filter_(D))*filter_(D)); 00059 00060 dimensionedScalar MMMM = average(magSqr(MM)); 00061 00062 if (MMMM.value() > VSMALL) 00063 { 00064 return average(LL && MM)/MMMM; 00065 } 00066 else 00067 { 00068 return 0.0; 00069 } 00070 } 00071 |
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#2 |
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Bernhard Grieser
Join Date: Mar 2010
Location: Zurich, Switzerland
Posts: 30
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I'd like to know that as well.
How's average(volScalarField) implemented? |
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#3 |
Member
Charlie
Join Date: Dec 2010
Location: USA
Posts: 85
Rep Power: 16 ![]() |
Hi,
See the source file about average(): http://foam.sourceforge.net/doc/Doxy...8C_source.html you can see some useful field functions( including average(),pow() etc) there |
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#4 | |
Member
Bernhard Grieser
Join Date: Mar 2010
Location: Zurich, Switzerland
Posts: 30
Rep Power: 16 ![]() |
Quote:
Regards, Bernhard |
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