turbGen.C

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#include "fft.H"
#include "turbGen.H"
#include "Kmesh.H"
#include "primitiveFields.H"
#include "Ek.H"
#include "mathematicalConstants.H"
 
 
// * * * * * * * * * * * * * * * * Constructors  * * * * * * * * * * * * * * //
 
Foam::turbGen::turbGen(const Kmesh& k, const scalar EA, const scalar K0)
:
    K_(k),
    Ea_(EA),
    k0_(K0),
    rndGen_(label(0))
{}
 
 
// * * * * * * * * * * * * * * * Member Functions  * * * * * * * * * * * * * //
 
Foam::vectorField Foam::turbGen::U()
{
    vectorField s(K_.size());
    scalarField rndPhases(K_.size());
 
    forAll(K_, i)
    {
        s[i] = rndGen_.sample01<vector>();
        rndPhases[i] = rndGen_.scalar01();
    }
 
    s = K_ ^ s;
    s = s/(mag(s) + 1.0e-20);
 
    s = Ek(Ea_, k0_, mag(K_))*s;
 
    complexVectorField up
    (
        fft::reverseTransform
        (
            ComplexField(cos(constant::mathematical::twoPi*rndPhases)*s,
            sin(constant::mathematical::twoPi*rndPhases)*s),
            K_.nn()
        )
    );
 
    return ReImSum(up);
}
 
 
// ************************************************************************* //