CFD Online Logo CFD Online URL
www.cfd-online.com
[Sponsors]
Home > Forums > Software User Forums > OpenFOAM > OpenFOAM Meshing & Mesh Conversion

[blockMesh] wedge patch is not planar

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

Like Tree1Likes
  • 1 Post By GerhardHolzinger

Reply
 
LinkBack Thread Tools Search this Thread Display Modes
Old   July 17, 2019, 11:08
Unhappy wedge patch is not planar
  #1
New Member
 
Majid Arjmandi
Join Date: Oct 2018
Posts: 21
Rep Power: 3
majidsvn7 is on a distinguished road
I had a problem with this axisymmetric geometry in blockMesh, I've used "movingCone" Tutorial from the openFOAM Tutorial folder and create the mesh alike in form this tutorial instruction.
After running blockMesh and checkMesh, I encounter with this error.I really need your help ...
the blockMesh file has been attached and the error is in below form.

"
--> FOAM Warning :
From function virtual void Foam::wedgePolyPatch::calcGeometry(Foam::PstreamBu ffers&)
in file meshes/polyMesh/polyPatches/constraint/wedge/wedgePolyPatch.C at line 70
Wedge patch 'front' is not planar.
At local face at (29.9502 4.462631 0.1948429) the normal (-3.334594e-16 -0.0436195 0.9990482) differs from the average normal (5.775252e-20 -0.04361943 0.9990482) by 5.931354e-15
Either correct the patch or split it into planar parts
--> FOAM Warning :
From function virtual void Foam::wedgePolyPatch::calcGeometry(Foam::PstreamBu ffers&)
in file meshes/polyMesh/polyPatches/constraint/wedge/wedgePolyPatch.C at line 70
Wedge patch 'front' is not planar.
At local face at (29.9502 4.475863 0.1954206) the normal (-8.614346e-16 -0.0436195 0.9990482) differs from the average normal (5.775252e-20 -0.04361943 0.9990482) by 5.931354e-15
Either correct the patch or split it into planar parts
--> FOAM Warning :
From function virtual void Foam::wedgePolyPatch::calcGeometry(Foam::PstreamBu ffers&)
in file meshes/polyMesh/polyPatches/constraint/wedge/wedgePolyPatch.C at line 70
Wedge patch 'front' is not planar.
At local face at (29.9502 4.489096 0.1959984) the normal (-4.730452e-16 -0.0436195 0.9990482) differs from the average normal (5.775252e-20 -0.04361943 0.9990482) by 5.931354e-15
Either correct the patch or split it into planar parts
"
checkMesh :
"
Checking geometry...
Overall domain bounding box (0 0 -0.1962872) (30 4.495712 0.1962872)
Mesh has 2 geometric (non-empty/wedge) directions (1 1 0)
Mesh has 3 solution (non-empty) directions (1 1 1)
Wedge back with angle 2.500002 degrees
***Wedge patch back not planar. Point (0 0.7939456 -0.03466441) is not in patch plane by 3.059446e-08 metre.
Boundary openness (1.555391e-19 -1.353222e-14 -2.299723e-13) OK.
Max cell openness = 2.073679e-16 OK.
Max aspect ratio = 12.04334 OK.
Minimum face area = 1.194516e-05. Maximum face area = 0.03910105. Face area magnitudes OK.
Min volume = 2.379515e-07. Max volume = 0.0005166389. Total volume = 23.42307. Cell volumes OK.
Mesh non-orthogonality Max: 0 average: 0
Non-orthogonality check OK.
Face pyramids OK.
Max skewness = 0.3307965 OK.
Coupled point location match (average 0) OK.

Failed 1 mesh checks.

End
"
Attached Files
File Type: c blockMeshDict.c (2.2 KB, 9 views)
majidsvn7 is offline   Reply With Quote

Old   July 18, 2019, 04:19
Default
  #2
Senior Member
 
Gerhard Holzinger
Join Date: Feb 2012
Location: Austria
Posts: 276
Rep Power: 23
GerhardHolzinger will become famous soon enoughGerhardHolzinger will become famous soon enough
It's most probably the precision of the points you provide in the file blockMeshDict.

Calculating the half-angle of the wedge, using python yields the following:

Code:
>>> import math
>>> a1=math.atan(0.1962872431/4.49571169971)
>>> a2=math.atan(0.1090484684/2.4976205539)
>>> a1
0.04363328263897132
>>> a2
0.04363323129548074
>>> a1/a2
1.0000011767061265
>>> math.degrees(a1)
2.5000029415145035
>>> math.degrees(a2)
2.4999999997491877
>>>
Also, the error message of OpenFOAM can be interpreted to point to insufficient precision:

Code:
At local face at (2.679282868525897 1.265350810419537 -0.05524640948741723) the normal (1.743214710593797e-16 -0.04361938736096225 -0.9990482215820488) differs from the average normal (-6.901918021236692e-20 -0.04361942583205133 -0.9990482199023509) by 1.482846079653545e-15
which translates to:

At the face X, the normal vector \vec{n_X} differs from the average normal vector (the normal vector averaged over all faces) \overline{\vec{n_i}} by very little (note the *e-15)
majidsvn7 likes this.
GerhardHolzinger is offline   Reply With Quote

Old   July 18, 2019, 05:01
Default
  #3
New Member
 
Majid Arjmandi
Join Date: Oct 2018
Posts: 21
Rep Power: 3
majidsvn7 is on a distinguished road
First of all, I need to thank you for paying attention to my work. By using your tips, The errors and warnings were resolved after applying the highest order of accuracy in defining the relevant points. I also used Python to calculate the half-angles of the wedge, but I often entered the points with less precision. Thank you again.
majidsvn7 is offline   Reply With Quote

Reply

Tags
blockmesh, planar

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
y+ and u+ values with low-Re RANS turbulence models: utility + testcase florian_krause OpenFOAM 113 June 25, 2019 00:58
steadyUniversalMRFFoam Tutorial fails in MixingPlane HenrikJohansson OpenFOAM Bugs 0 February 14, 2019 04:48
[Other] Wedge patch '*' is not planar LilumDaru OpenFOAM Meshing & Mesh Conversion 5 February 1, 2018 15:51
Near wall treatment in k-omega SST Arnoldinho OpenFOAM Running, Solving & CFD 38 March 8, 2017 13:48
[Gmsh] Import gmsh msh to Foam adorean OpenFOAM Meshing & Mesh Conversion 24 April 27, 2005 08:19


All times are GMT -4. The time now is 00:32.