[rawdoggity]

Hey all, new OpenFOAM user here. Using v2.3.1, I'm trying to run a lid-driven cavity flow simulation on a DEM of a mountain range converted into STL geometry as described by:

http://www4.ncsu.edu/~ejhardi2/OF_GRASS_Geom.pdf

So far, everything works beautifully and I have no trouble refining the geometry with blockMesh > snappyHexMesh -overwrite and calculating surface shear stress with icoFoam > wallShearStress -latestTime. However, I am having trouble sampling the results in 'wallShearStress'. I'm using a sample dictionary copied verbatim from the example given above that looks like this:

/* * * * * * * * * * * * * * * * * * * * * * * * * * * * *\
setFormat xmgr;

surfaceFormat raw;

interpolationScheme cellPoint;

fields
(
wallShearStress
);

sets
(
);

surfaces
(
wall
{
type patch;
patchName terrain_terrain;
}
);

/* * * * * * * * * * * * * * * * * * * * * * * * * * * * *\

However, when I run "sample" I receive the following error:

keyword patches is undefined in dictionary "/Users/ecr/browan/OpenFOAM/browan-2.3.1/run/tutorials/incompressible/icoFoam/mteveresttutorial/system/sampleDict.surfaces"

It's clear to me that the tutorial is based off an older version of OpenFOAM and that the sampleDict syntax has changed since moving to 2.3.1, but I can't find an example of the proper syntax (including 'patches' and 'type' within the 'surfaces' dictionary) anywhere. I'm sure this is a simple fix... can anybody tell me how I should be writing this? Perhaps post an example to use for reference?

[alexeym]

Hi,

Usually examples of dictionaries are placed along the sources of the utilities, in case of sample, you can find the dictionary in $FOAM_APP/applications/utilities/postProcessing/sampling/sample folder.

Here's an excerpt from the file:

    walls_constant
    {
        type            patch;
        patches         ( ".*Wall.*" );
        // Optional: whether to leave as faces (=default) or triangulate
        // triangulate     false;
    }

    walls_interpolated
    {
        type            patch;
        patches         ( ".*Wall.*" );
        interpolate     true;
        // Optional: whether to leave as faces (=default) or triangulate
        // triangulate     false;
    }