foam-extend4.1-coherent-io/applications/solvers/solidMechanics/elasticOrthoNonLinULSolidFoam/rotateFields.H

//--------------------------------------------------//
//- rotate fields
//--------------------------------------------------//
{
  Info << "Rotating fields" << endl;

  volTensorField F = I + gradDU;

  U += DU;

  epsilon += DEpsilon;

  sigma += DSigma;

  volTensorField Finv = inv(F);

  volScalarField J = det(F);
  if(min(J.internalField()) < 0)
    {
      FatalErrorIn(args.executable())
	<< "Negative Jacobian - a cell volume has become negative!"
	<< exit(FatalError);
    }

  rho = rho/J;

  n = mesh.Sf()/mesh.magSf();

  //- rotate strain
  //epsilon = symm(Finv & epsilon & Finv.T());
  epsilon = transform(Finv, epsilon);

  //- rotate stress
  //sigma  = 1/J * symm(F.T() & sigma & F);
  sigma = (1/J) * transform(F.T(), sigma);

  //- rotate elastic constitutive tensor
  C = transform(F.T(), C);

  // - update implicit stiffness tensor
  forAll(K, celli)
    {
      K[celli].xx() = C[celli].xxxx();
      K[celli].yy() = C[celli].yyyy();
      K[celli].zz() = C[celli].zzzz();
    }
  K.correctBoundaryConditions();
}