extrudeMesh partially extrude faces into separate mesh

Summary

When using

constructFrom patch;

it does not work unless all points are extruded. This is the default behaviour so should not be noticed. However it can happen when doing implicit extrusion through e.g. thermalBaffle bc.

Example case

hex2x2.tgz

extrudeMesh.C

• compile above extrudeMesh. It has additional code to not extrude non-manifold points.

Run ./Allrun to do

• blockMesh
• remove 2 diagonal cells
• trying to extrude a non-manifold patch

What is the current bug behaviour?

Crash with illegal point index.

Environment information

• OpenFOAM version : v2012

Possible fixes

• The addPatchCellLayer topo change class should not check for non-extruded points. Attached the fix (needs to be tested more):

addPatchCellLayer.C

• potentially the code to detect non-manifoldness should be included in extrudeMesh.C (stand-alone app) and extrudePatchMesh (extruded fvMesh, used in e.g. thermal baffle bcs)

added bug label

• addPatchCellLayer can be run with not extruding points (so e.g. generating wedges) but in construct layer-only (v.s. adding layers to existing mesh) it will need each face on the patch to have at least one extruded point. Otherwise there is no volume/cell extruded (faces cannot be stand-alone, only exist on a cell). This is detected in the code in attached extrudeMesh.C where it gives a FatalError if there is a face without any extrusion.

Note that this should not be a problem when adding a layer to an existing mesh.

A work around would be to pre-filter the patch/faceZone to exclude faces where all the points are non-manifold:

• checkMesh -allTopology will write nonManifoldPoints pointSet
• faceSet source pointToFace nonManifoldPoints all (or equivalent in topoSet syntax) can be used to select faces where all the points are in the pointSet.

mentioned in commit 3273e6c2

mentioned in commit cd2d81b7