[steph79]

Hi,

I'm using OpenFOAM version 1.7 and would like to utilise a patch which extrapolates pressure values from the fluid volume onto a wall as opposed to forcing the pressure gradient (normal to the wall) to equal zero, i.e. the zeroGradient patch.

Will the "calculated" patch be able to achieve this for me? If so, how should I go about enabling it for use with icoFoam? I suspect I need to add a line in Make/options and then compile an alternative solver but I've never done that before so I could use some help. This is the error message I receive when I try to use the calculated patch with the standard icoFoam;

--> FOAM FATAL ERROR: 

    gradientInternalCoeffs cannot be called for a calculatedFvPatchField
    on patch plate of field p in file "/home/mitchs/OpenFOAM/Test/0/p"
    You are probably trying to solve for a field with a default boundary condition.

    From function calculatedFvPatchField<Type>::gradientInternalCoeffs() const
    in file fields/fvPatchFields/basic/calculated/calculatedFvPatchField.C at line 186.

FOAM exiting