[Origami]

I am modelling an urban area with buildings on non-flat terrain. I want to add layers to the surface of buildings and terrains. Below the log file of running snappyHexMesh. I don’t understand what it means for “layers”, “overall [m]” and “thickness [%]”. Can someone please help?

patch faces layers overall thickness
[m] [%]
----- ----- ------ --- ---
buildingSurroundings 9147 2.14 0.138 68.9
innerTerrain 583214 0.00712 0.00303 0.163

Below an excerpt of snappyHexMeshDict for adding layers.

addLayersControls
{
minMedialAxisAngle 90;
relativeSizes true;
layers
{
buildingSurroundings
{
nSurfaceLayers 3;
relativeSizes true;
minThickness 0.1;
finalLayerThickness 0.6;
expansionRatio 1.1;
}
innerTerrain
{
nSurfaceLayers 4;
relativeSizes false;
minThickness 0.2;
firstLayerThickness 0.4;
expansionRatio 1.1;
}
}
expansionRatio 1.2;
firstLayerThickness 1;
minThickness 0.3;
nGrow 0;
featureAngle 130;
nRelaxIter 5;
nSmoothSurfaceNormals 1;
nSmoothNormals 3;
nSmoothThickness 10;
maxFaceThicknessRatio 0.5;
maxThicknessToMedialRatio 0.3;
minMedianAxisAngle 90;
nBufferCellsNoExtrude 0;
nLayerIter 50;
nRelaxedIter 20;
}