[hmrbcnt]

I'm trying to find a way where I can sample the maximum pressure on a given face of an STL I've imported.


So, say I've imported an STL in the shape of a cube within the center of my mesh, and run my simulation using a solver.



Would there be a more efficient way of taking the maximum pressure, or at least the pressure in the center of the face of each side of the cube without having to manually place the probe filters?

[Nomis]

Hi Homer,



assuming that the cube stl is a boundary of your domain you can use a functionObject in your controlDict to monitor the max pressure:

functions
{
          NAME     { 
                  type            surfaceFieldValue; 
                  libs             ("libfieldFunctionObjects.so"); 
                  fields          (p); 
                  writeFields no; 
                  regionType patch; 
                  name         NAMEOFPATCH; 
                  operation    max;  // also average or weighted average are possible
                  }
  }

Hope this helps. Greeting Simon

[hmrbcnt]

Originally Posted by Nomis

Hi Homer,



assuming that the cube stl is a boundary of your domain you can use a functionObject in your controlDict to monitor the max pressure:

functions
{
          NAME     { 
                  type            surfaceFieldValue; 
                  libs             ("libfieldFunctionObjects.so"); 
                  fields          (p); 
                  writeFields no; 
                  regionType patch; 
                  name         NAMEOFPATCH; 
                  operation    max;  // also average or weighted average are possible
                  }
  }

Hope this helps. Greeting Simon

Hello, Simon. Thank you for your help! I'm trying to run my code with that openfoam function, but I get some segmentation fault errors, as well as errors about duplicate entries. Here is the segmentation fault error from my log.Solver file.

surfaceFieldValue wallsCopy write:
[2] #0  Foam::error::printStack(Foam::Ostream&) at ??:?
[2] #1  Foam::sigSegv::sigHandler(int) at ??:?
[2] #2  ? in "/lib/x86_64-linux-gnu/libc.so.6"
[2] #3  Foam::tmp<Foam::Field<double> > Foam::functionObjects::fieldValues::surfaceFieldValue::filterField<double>(Foam::GeometricField<double, Foam::fvPatchField, Foam::volMesh> const&, bool) const at ??:?
[2] #4  Foam::tmp<Foam::Field<double> > Foam::functionObjects::fieldValues::surfaceFieldValue::getFieldValues<double>(Foam::word const&, bool, bool) const at ??:?
[2] #5  bool Foam::functionObjects::fieldValues::surfaceFieldValue::writeValues<double>(Foam::word const&, Foam::Field<double> const&, bool) at ??:?
[2] #6  Foam::functionObjects::fieldValues::surfaceFieldValue::write() at ??:?
[2] #7  Foam::functionObjectList::execute() at ??:?
[2] #8  Foam::Time::run() const at ??:?
[2] #9  ? in "/home/hmrbcnt/OpenFOAM/hmrbcnt-7/platforms/linux64GccDPInt32Opt/bin/blastFoam"
[2] #10  __libc_start_main in "/lib/x86_64-linux-gnu/libc.so.6"
[2] #11  ?[hmrbcnt:09547] *** Process received signal ***
[hmrbcnt:09547] Signal: Segmentation fault (11)
[hmrbcnt:09547] Signal code:  (-6)
[hmrbcnt:09547] Failing at address: 0x3e80000254b
[hmrbcnt:09547] [ 0] /lib/x86_64-linux-gnu/libc.so.6(+0x3f040)[0x7f65655b6040]
[hmrbcnt:09547] [ 1] /lib/x86_64-linux-gnu/libc.so.6(gsignal+0xc7)[0x7f65655b5fb7]
[hmrbcnt:09547] [ 2] /lib/x86_64-linux-gnu/libc.so.6(+0x3f040)[0x7f65655b6040]
[hmrbcnt:09547] [ 3] /home/hmrbcnt/OpenFOAM/OpenFOAM-7/platforms/linux64GccDPInt32Opt/lib/libfieldFunctionObjects.so(_ZNK4Foam15functionObjects11fieldValues17surfaceFieldValue11filterFieldIdEENS_3tmpINS_5FieldIT_EEEERKNS_14GeometricFieldIS6_NS_12fvPatchFieldENS_7volMeshEEEb+0xae)[0x7f653e9f038e]
[hmrbcnt:09547] [ 4] /home/hmrbcnt/OpenFOAM/OpenFOAM-7/platforms/linux64GccDPInt32Opt/lib/libfieldFunctionObjects.so(_ZNK4Foam15functionObjects11fieldValues17surfaceFieldValue14getFieldValuesIdEENS_3tmpINS_5FieldIT_EEEERKNS_4wordEbb+0x2d2)[0x7f653ea2f912]
[hmrbcnt:09547] [ 5] /home/hmrbcnt/OpenFOAM/OpenFOAM-7/platforms/linux64GccDPInt32Opt/lib/libfieldFunctionObjects.so(_ZN4Foam15functionObjects11fieldValues17surfaceFieldValue11writeValuesIdEEbRKNS_4wordERKNS_5FieldIdEEb+0xa9)[0x7f653ea2fb19]
[hmrbcnt:09547] [ 6] /home/hmrbcnt/OpenFOAM/OpenFOAM-7/platforms/linux64GccDPInt32Opt/lib/libfieldFunctionObjects.so(_ZN4Foam15functionObjects11fieldValues17surfaceFieldValue5writeEv+0x1ae)[0x7f653e9e6ade]
[hmrbcnt:09547] [ 7]  in "/home/hmrbcnt/OpenFOAM/hmrbcnt-7/platforms/linux64GccDPInt32Opt/bin/blastFoam"
/home/hmrbcnt/OpenFOAM/OpenFOAM-7/platforms/linux64GccDPInt32Opt/lib/libOpenFOAM.so(_ZN4Foam18functionObjectList7executeEv+0xe3)[0x7f6566928293]
[hmrbcnt:09547] [ 8] /home/hmrbcnt/OpenFOAM/OpenFOAM-7/platforms/linux64GccDPInt32Opt/lib/libOpenFOAM.so(_ZNK4Foam4Time3runEv+0xe2)[0x7f656693bc62]
[hmrbcnt:09547] [ 9] blastFoam(+0x6612)[0x55b756606612]
[hmrbcnt:09547] [10] /lib/x86_64-linux-gnu/libc.so.6(__libc_start_main+0xe7)[0x7f6565598bf7]
[hmrbcnt:09547] [11] blastFoam(+0x771a)[0x55b75660771a]
[hmrbcnt:09547] *** End of error message ***

Any idea what might be causing this? I'm using the blastFoam solver, if the solver matters. Thank you

[Nomis]

I don't now if the usual functionObjects are supported by blastFoam....
Please check the large number of tutorials within blastFoam and the detailed manual.

There might be one case monitoring the pressure on a patch,
otherwise ask in the blastFoam section of cfd-online.

Greetings Simon

[hmrbcnt]

Hello, thank you once again!


Apparently, most function objects are usable in BlastFoam, but that pressure was a volFieldValue instead of a surfaceFieldValue, so I should use a volFieldValue type instead. I'll have to try this out first.





Thank you so much for your help!