CFD Online Logo CFD Online URL
Home > Forums > Software User Forums > OpenFOAM > OpenFOAM Meshing & Mesh Conversion

[snappyHexMesh] problems resolving small mesh

Register Blogs Members List Search Today's Posts Mark Forums Read

LinkBack Thread Tools Search this Thread Display Modes
Old   September 21, 2020, 13:05
Default problems resolving small mesh
Senior Member
Join Date: Nov 2019
Location: Compiègne, France
Posts: 125
Rep Power: 5
otaolafr is on a distinguished road
I am looking for some help with snappyHex or if someone can see another problem from a previous step.

I need to mesh really small geometries with small repetitive internal structures (3mm3) ( the total bounding box is (-1.0842e-19 -9.2767e-19 -1.38778e-17) (0.00505 0.00505 0.201133))

for the background mesh, I use blockMesh with cubic cells and a cell size of 0.002 (also tried 0.001/0.0015/0.0025). For the geometry itself, I triangulate it with salome with NETGEN 2D and wire discretization and local lenght of 5e-05 (i tried also 2.5e-5).

for the snappyHex
the castelated controls where:
maxLocalCells 2000000
maxGlobalCells 13000000
level ref (1 1) (tried 2 2, 3 3, 4 4, 5 5 and 6 6) for the howl region.
for the snapControls:
nSmoothPatch 5 (also 7)
tolerance 2
nSolveIter 300 (also 350)
nRelaxIter 4 (also 8)
nFeatureSnapIter 30 (also 100)

and with explicitFeatureSnap on.
the feature detection works correctly see attached pictures...
the issues I am having is that the snapp of the geometry to go at least similar in a "look" i need to go at least up to level 5 5 of refiment, but when i do this the checking mesh bigings to give errors (higher the level the more face error i am facing):
non-orthogonality > 65 degrees :170 and faces with face pyramid volume < 1e-13: around 20000000 for the best results.

I am adding the results from the surfaceCheck of the stl and also the checkMesh -allGeometry -allTopology


I know that it is a proble of size of the geometry itself.. but I need really need to mesh this geometry as they idea is to compare it with experimental results so any help would be apreciated
image link:

any guidance/help or pointing in a direction would be appreciate it.

Last edited by otaolafr; September 21, 2020 at 14:14.
otaolafr is offline   Reply With Quote


check mesh, ilegal faces, salome meshing, snappyhexmesh 3d

Thread Tools Search this Thread
Search this Thread:

Advanced Search
Display Modes

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Trackbacks are Off
Pingbacks are On
Refbacks are On

Similar Threads
Thread Thread Starter Forum Replies Last Post
decomposePar problem: Cell 0contains face labels out of range vaina74 OpenFOAM Pre-Processing 37 July 20, 2020 06:38
[snappyHexMesh] problems generating clean mesh Christian_tt OpenFOAM Meshing & Mesh Conversion 2 June 20, 2019 06:39
[ANSYS Meshing] First layter thickness on mesh causing problems Rik102 ANSYS Meshing & Geometry 0 November 4, 2016 10:51
Star CCM Overset Mesh Error (Rotating Turbine) thezack Siemens 7 October 12, 2016 12:14
[snappyHexMesh] No layers in a small gap bobburnquist OpenFOAM Meshing & Mesh Conversion 6 August 26, 2015 10:38

All times are GMT -4. The time now is 11:57.