0000696: Collapsing edges in extrudeMesh destroys mesh

ID	Project	Category	View Status	Date Submitted	Last Update

0000696	OpenFOAM	Bug	public	2012-12-06 14:21	2012-12-07 14:11

Reporter	martinB	Assigned To	~~user4~~
Priority	low	Severity	trivial	Reproducibility	always
Status	resolved	Resolution	fixed
Platform	Linux	OS	OpenSUSE	OS Version	12.1

Summary	0000696: Collapsing edges in extrudeMesh destroys mesh
Description	If a mesh contains very large and very small elements the collapsing of edges destroys the resulting mesh from the extrudeMesh utility. Output of the utility is: """ ... Collapsing edges < 2e-05 ... Merging edge (0 1) since length 1.56918194e-05 << 2e-05 Merging edge (0 11) since length 2.19605425e-06 << 2e-05 ... Cell:0 uses faces:6(0 1 2 3 4 350500) of which too many are marked for removal: 0 1 2 3 4 350500 Cell:1 uses faces:6(5 6 7 8 350583 0) of which too many are marked for removal: 5 6 7 8 350583 0 ... """ As a workaround line 669 in extrudeMesh.C can be modified from const scalar mergeDim = 1E-4 * bb.minDim(); to const scalar mergeDim = 1E-12 * bb.minDim(); If the collapsing edges feature should not be removed completely, an additional option "-noEdgeCollapsing" would be useful, may be with a value for the relative size factor.
Steps To Reproduce	- untar the attached archive "big_to_small_tube.tar.gz" - run blockMesh - run extrudeMesh --> Failure After modification of extrudeMesh.C the mesh extrusion works perfectly.
Tags	No tags attached.

Date Modified	Username	Field	Change
2012-12-06 14:21	martinB	New Issue
2012-12-06 14:21	martinB	File Added: big_to_small_tube.tar.gz
2012-12-07 14:11	~~user4~~	Note Added: 0001814
2012-12-07 14:11	~~user4~~	Status	new => resolved
2012-12-07 14:11	~~user4~~	Fixed in Version	=> 2.1.x
2012-12-07 14:11	~~user4~~	Resolution	open => fixed
2012-12-07 14:11	~~user4~~	Assigned To	=> user4

martinB 2012-12-06 14:21 reporter	big_to_small_tube.tar.gz (2,217 bytes)

~~user4~~ 2012-12-07 14:11 ~0001814	I've pushed a user setting for the tolerance in 21x to extrudeMesh. See the extrudeMeshDict in the source directory. commit 840bd62f110a572fc216676c2451f10b3cdc89ca Thanks for reporting.