comment

applications/utilities/mesh/generation/snappyHexMesh/snappyHexMeshDict

@@ -292,6 +292,7 @@ meshQualityControls
     minFlatness 0.5;
 
     //- Minimum pyramid volume. Is absolute volume of cell pyramid.
+    //  Set to a sensible fraction of the smallest cell volume expected.
     //  Set to very negative number (e.g. -1E30) to disable.
     minVol 1e-13;