1 if(divSigmaExpMethod == "standard")
3 //- calculating the full gradient has good convergence and no high freq oscillations
4 divSigmaExp = fvc::div(C && epsilon) - fvc::div(K & gradU);
6 else if(divSigmaExpMethod == "surface")
8 //- this form seems to have the best convergence
13 (n & (Cf && fvc::interpolate(symm(gradU))))
14 - (n & (Kf & fvc::interpolate(gradU)))
18 else if(divSigmaExpMethod == "laplacian")
20 //- causes high freq oscillations and slow convergence
21 divSigmaExp = fvc::div(sigma) - fvc::laplacian(K, U);
25 FatalErrorIn(args.executable())
26 << "divSigmaExp method " << divSigmaExpMethod << " not found!" << endl;