[umbi_more]

Hello!


I am solving the following one dimensional problem

with BC


This problem has analytical solution and I am using it as a benchmark before moving to more complicate things. However, I do not manage to get it right.


What did untill now (assuming ) is to use laplacianFoam with the source term defined in fvOptions as

source1
{
    type            scalarSemiImplicitSource;
    active          true;
    selectionMode   points; // all, cellSet, cellZone, points
    volumeMode      specific; // absolute,specific
    points
    (
        (0 0 0)
    );
    injectionRateSuSp
    {
        T        (1.0  0);
    }
}

Where T=1.0 is the value of f(x) at x=0.


I have run it with the boundary conditions:

 dimensions [ 0 0 0 1 0 0 0 ];

internalField uniform 350;

boundaryField
{
  symmetryPlanes
  {
    type symmetry;
  }
  coldSide
  {
    type                groovyBC;
    variables           2("H=60.0;" "k=350.0;");
    valueExpression     "0.0"; ;
    gradientExpression  "0.0";
    fractionExpression  "1/(1+2*k/(H*mag(delta())))";
  }
  hotSide
  {
    type fixedGradient;
    gradient uniform 0;
  }

and the transport properties

DT              DT [ 0 2 -1 0 0 0 0] 350;

What I get is a solution that is constant for x<0 and linearly decreasing for x>0 which is what I expect but the values of the solution are wrong compared to the analytical solution. Moreover, I tried to solve on a 100 cell and 400 cell uniform grid and I got very different results even if the volumeMode is set to specific.


I thank you for any help or hint you can provide me.
Umberto