View Issue Details

IDProjectCategoryView StatusLast Update
0003659OpenFOAMBugpublic2021-04-11 19:38
Reportershock77Assigned Tohenry 
PrioritynormalSeverityminorReproducibilityalways
Status closedResolutionsuspended 
PlatformGNU/LinuxOSUbuntuOS Version12.04
Product Version7 
Fixed in Version 
Summary0003659: Wrong sum of physical quantities due to wrong oriented face normals in spite of usage of orientFaceZone
DescriptionSorry for the previous post, the paged reloaded and the issue has been submitted incompletely. This is definitely a bug.

Concerning the bug:

To sample the mass flow rate through a faceZone with the operation "sum" the face normals of the faceZones are aligned with orientFaceZone.
The face normals look well aligned in paraview after that operation, before they were chaotic. After decomposing and running the case, it is clear that the flux is again calculated with the previous oriented face normals and the face normal correction is ignored. This leads to wrong results.

I have prepared a simplified testcase. Please note that the patch "outlet" and the faceZone "preOutlet" are very close to each other and should have the same result.
Looking at the results (the postProcessing folder is attached) it shows, that the results are different. If sumMag instead of sum is used, the result is correct.
This might be a work around in my case with no recircularisation, eddies etc., but might be a problem for other users:

sum outlet (patch): 1.43
sum preOutlet (faceZone): 0.698
sumMag preOutlet (faceZone): 1.43
Steps To ReproducegmshToFoam meshblock.msh
surfaceFeatureExtract
snappyHexMesh -overwrite
transformPoints -scale '(0.001 0.001 0.001)'
topoSet
createPatch -overwrite
constant/polymesh/boundary --> set type to symmetry of symmetryPlane
orientFaceZone preOutlet '(0 0 1)'
decomposePar
mpirun -np 8 rhoCentralFoam -parallel
Additional Information
To see the face normals in paraview use the filter--> generate surface normals (remove the "splitting" and "consitency") and use glyphs to display the face normals.
I am using openfoam7 to prepare the case. I am running the case with openfoam4.1 or openfoam5 on a work station (new versions do not work there).
TagsNo tags attached.

Activities

shock77

2021-04-11 17:37

reporter  

testcase1.zip (1,779,892 bytes)

henry

2021-04-11 17:54

manager   ~0011973

I don't think this is a bug but incorrect usage. However if you believe it is a bug can you provide a patch to resolve it? If not you will need to provide maintenance funding for us to look into it for you.

shock77

2021-04-11 18:42

reporter   ~0011974

I am sure it is a bug, but nobody is infallible. However I don't think I am skilled enough in coding to resolve this bug, but I will try it.

Sorry it seems I got the concept of the Issue tracking wrong. I actually wanted to report this bug to prevent other users to suffer from it, but I have no patch to resolve this issue. I have actually been asked to report the issue here. I have a work around for my applications. However it is clear, that this approach is not suitable for other applications. Unfortunately I don't have the means to pay you to resolve the issue.

henry

2021-04-11 19:15

manager   ~0011975

> Sorry it seems I got the concept of the Issue tracking wrong. I actually wanted to report this bug to prevent other users to suffer from it, but I have no patch to resolve this issue. I have actually been asked to report the issue here.

Can the person who asked you to report the problem you are having provide funding for us to work on it? If not can they provide a patch? If not who should fund us to work on it for you? We release OpenFOAM entirely open-source so we do not receive licence fees and the maintenance funding we have secured so far is not sufficient to cover the substantial cost of maintaining such a large and complex software package:

https://openfoam.org/news/funding-2021/

shock77

2021-04-11 19:33

reporter   ~0011976

I have already apologized. I know its hard to get funding and I don't want you to work on me. I have never asked for that. I reported it with the intention to prevent other users to have troubles with that issue, that's all. I am really happy that such a great software is freely accessible for all users worldwide.

 I won't report anything if I have no patch to resolve the issue. Please just close this issue.

henry

2021-04-11 19:38

manager   ~0011977

Likely user support, pending funding.

Issue History

Date Modified Username Field Change
2021-04-11 17:37 shock77 New Issue
2021-04-11 17:37 shock77 File Added: testcase1.zip
2021-04-11 17:54 henry Note Added: 0011973
2021-04-11 18:42 shock77 Note Added: 0011974
2021-04-11 19:15 henry Note Added: 0011975
2021-04-11 19:33 shock77 Note Added: 0011976
2021-04-11 19:38 henry Assigned To => henry
2021-04-11 19:38 henry Status new => closed
2021-04-11 19:38 henry Resolution open => suspended
2021-04-11 19:38 henry Note Added: 0011977