CFD Online Discussion Forums - how to initalize an expressionField for the walldistance?

Hi Foamers,
I need to compute a field in complex geometries which stores the distance to the nearest wall for the whole field. This is needed for a custom meshing technique for LES. I tried something like:

Code:

alpha2Field {

        type         expressionField;

        writeControl    writeTime;

        writeTime    0;

        fieldName     alpha2;

        expression     "dist()";

        autowrite    true;

    }

unfortunately I am not able to aviod the Error like:

Code:



Creating expression field alpha2 ...Selecting patchDistMethod meshWave

[0] 

[0] 

[0] --> FOAM FATAL ERROR: 

[0] At least one plane coefficient must have a value

[0] 

[0]     From function void Foam::plane::calcPntAndVec(const scalarList&)

[0]     in file meshes/primitiveShapes/plane/plane.C at line 51.

[0]

Im usig OF4.1 on ubuntu 16.04 LTS
I hope someone is able and wants to help me. and cant imagine that its endless complicated.
regards,
David