View Issue Details

IDProjectCategoryView StatusLast Update
0001747OpenFOAMBugpublic2017-06-30 10:41
Reporteruser1172Assigned Tochris  
PrioritynormalSeverityminorReproducibilityalways
Status closedResolutionfixed 
PlatformGNU/LinuxOSUbuntuOS Version14.04
Summary0001747: SnappyHexMesh creates extra cell regions
DescriptionSnappyHexMesh retains cell regions that do not contain the locationInMesh point.

According to checkMesh there are 7 regions. At least 4 of the regions are approximatly located around the point (-4989.605469, 1333.152832, 1944.076294)

See the attached mesh setup files.
Steps To Reproduceunzip the attached small_regions.zip file and run run_snappy.sh
TagsNo tags attached.

Activities

user1172

2015-06-15 23:20

 

small_regions.zip (135,483 bytes)

user4

2015-06-16 09:17

  ~0004947

I will look into this. What sizes does checkMesh report for these regions? Do you have one large regions and some small ones? As a workaround you can run snappyHexMesh for refinement only, run

splitMeshRegions -largestOnly

(this splits off the largest region as a separate mesh region), move the resulting largestOnly/polyMesh back to constant/ and restart snappyHexMesh (disable refinement)

user1172

2015-06-16 15:06

  ~0004957

Last edited: 2015-06-16 15:07

Here's the checkMesh output (the 6 single cell regions have a small volume):

   *Number of regions: 7
    The mesh has multiple regions which are not connected by any face.
  <<Writing region information to "0/cellToRegion"
  <<Writing region 0 with 18464 cells to cellSet region0
  <<Writing region 1 with 1 cells to cellSet region1
  <<Writing region 2 with 1 cells to cellSet region2
  <<Writing region 3 with 1 cells to cellSet region3
  <<Writing region 4 with 1 cells to cellSet region4
  <<Writing region 5 with 1 cells to cellSet region5
  <<Writing region 6 with 1 cells to cellSet region6

I'll also include an image of the small cell regions.

I worked around this issue by changing the geometry.

user1172

2015-06-16 15:08

 

mesh_bug.jpg (52,576 bytes)   
mesh_bug.jpg (52,576 bytes)   

chris

2017-06-30 10:41

manager   ~0008293

Reporter found workaround, provided no further feedback on original issue

Issue History

Date Modified Username Field Change
2015-06-15 23:20 user1172 New Issue
2015-06-15 23:20 user1172 File Added: small_regions.zip
2015-06-16 09:17 user4 Note Added: 0004947
2015-06-16 15:06 user1172 Note Added: 0004957
2015-06-16 15:07 user1172 Note Edited: 0004957
2015-06-16 15:08 user1172 File Added: mesh_bug.jpg
2017-06-30 10:41 chris Assigned To => chris
2017-06-30 10:41 chris Status new => closed
2017-06-30 10:41 chris Resolution open => fixed
2017-06-30 10:41 chris Note Added: 0008293