applications/solvers/solidMechanics/elasticSolidFoam/aitkenRelaxation.H

   1 // aitken acceleration
   2
   3 aitkenDelta.storePrevIter();
   4
   5 // update delta
   6 aitkenDelta = (U - U.prevIter()) / aitkenInitialRes;
   7
   8 // update relaxation factor
   9 if(iCorr == 0)
  10   {
  11     aitkenTheta = 0.1;
  12   }
  13  else
  14    {
  15      vectorField b = aitkenDelta.internalField() - aitkenDelta.prevIter().internalField();
  16      // scalar sumMagB = gSum(mag(b));
  17      scalar sumMagB = gSum(magSqr(b));
  18      if(sumMagB < SMALL)
  19        {
  20          // Warning << "Aitken under-relaxation: denominator less then SMALL"
  21          // << endl;
  22          sumMagB += SMALL;
  23        }
  24
  25      aitkenTheta = -aitkenTheta*
  26        gSum(aitkenDelta.prevIter().internalField() & b)
  27        /
  28        sumMagB;
  29    }
  30
  31 // correction to the latest U
  32 U += aitkenTheta*aitkenDelta*aitkenInitialRes;