Eigenmode frequency always 0?

[kwahoo]

For some reason, the Eigenmode frequency field (in the "Data" tab) is editable for me and it is always set to 0,00.

The file.

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OS: Ubuntu 15.10
Word size of OS: 64-bit
Word size of FreeCAD: 64-bit
Version: 0.16.5919 (Git)
Build type: None
Branch: master
Hash: 081bc6b10708c244577dd1baf73070be47eb3109
Python version: 2.7.10
Qt version: 4.8.6
Coin version: 4.0.0a
OCC version: 6.8.0.oce-0.17

[bernd]

works for me with your file and with other models. The field is read only too. First thing you could do is check dat file of calculix. Values reach from 14.64316 to 19.50663 for your model. Are you going to build a scooter?

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     E I G E N V A L U E   O U T P U T

 MODE NO    EIGENVALUE                       FREQUENCY   
                                     REAL PART            IMAGINARY PART
                           (RAD/TIME)      (CYCLES/TIME     (RAD/TIME)

      1   0.8465049E+04   0.9200570E+02   0.1464316E+02   0.0000000E+00
      2   0.8469107E+04   0.9202775E+02   0.1464667E+02   0.0000000E+00
      3   0.6428316E+05   0.2535412E+03   0.4035234E+02   0.0000000E+00
      4   0.6431361E+05   0.2536013E+03   0.4036190E+02   0.0000000E+00
      5   0.2468422E+06   0.4968321E+03   0.7907329E+02   0.0000000E+00
      6   0.2469575E+06   0.4969482E+03   0.7909176E+02   0.0000000E+00
      7   0.6737729E+06   0.8208367E+03   0.1306402E+03   0.0000000E+00
      8   0.6740854E+06   0.8210270E+03   0.1306705E+03   0.0000000E+00
      9   0.1501506E+07   0.1225360E+04   0.1950220E+03   0.0000000E+00
     10   0.1502188E+07   0.1225638E+04   0.1950663E+03   0.0000000E+00

OS: Debian GNU/Linux 8.2 (jessie)
Word size of OS: 64-bit
Word size of FreeCAD: 64-bit
Version: 0.16.6004 (Git)
Build type: Unknown
Branch: master
Hash: 3414ec8af17500ed2880ac661a602f73e2da4826
Python version: 2.7.9
Qt version: 4.8.6
Coin version: 4.0.0a
OCC version: 6.7.0

[kwahoo]

Strange, but Revolution_Mesh.dat looks fine. Things what I did so far:
updated FC version to 0.16.6018,
tried LC_ALL=C freecad
removed ~/.FreeCAD

No luck so far...

[bernd]

...No luck so far...

try to import by python ...

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import ccxDatReader
file = '/tmp/Revolution_Mesh.dat'
result = ccxDatReader.readResult(file)
result

output for your model

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>>> import ccxDatReader
>>> file = '/tmp/Revolution_Mesh.dat'
>>> result = ccxDatReader.readResult(file)
>>> result
[{'eigenmode': 1, 'frequency': 14.64316}, {'eigenmode': 2, 'frequency': 14.64667}, {'eigenmode': 3, 'frequency': 40.35234}, {'eigenmode': 4, 'frequency': 40.3619}, {'eigenmode': 5, 'frequency': 79.07329}, {'eigenmode': 6, 'frequency': 79.09176}, {'eigenmode': 7, 'frequency': 130.6402}, {'eigenmode': 8, 'frequency': 130.6705}, {'eigenmode': 9, 'frequency': 195.022}, {'eigenmode': 10, 'frequency': 195.0663}]

[kwahoo]

My output:

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[{'eigenmode': 1, 'frequency': 14.64316}, {'eigenmode': 2, 'frequency': 14.64667}, {'eigenmode': 3, 'frequency': 40.35234}, {'eigenmode': 4, 'frequency': 40.3619}, {'eigenmode': 5, 'frequency': 79.07329}, {'eigenmode': 6, 'frequency': 79.09176}, {'eigenmode': 7, 'frequency': 130.6402}, {'eigenmode': 8, 'frequency': 130.6705}, {'eigenmode': 9, 'frequency': 195.022}, {'eigenmode': 10, 'frequency': 195.0663}]

For some reason, scrolling Data Tab is laggy, while View Tab is not.

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OS: Ubuntu 15.10
Word size of OS: 64-bit
Word size of FreeCAD: 64-bit
Version: 0.16.6018 (Git)
Build type: None
Branch: master
Hash: c67b2bed45ac8b7bf6f7eda3c22541a26fce571a
Python version: 2.7.10
Qt version: 4.8.6
Coin version: 4.0.0a
OCC version: 6.8.0.oce-0.17

[bernd]

I may found culprit. Try to use the quick analysis (FEM --> Run CalculiX ccx) instead off the solver job control icon. There seams a bug in solver job control if frequency analysis is used. Could you just give feedback?

[kwahoo]

Confirmed!

[bernd]

Thanks!

For reference:
the results could be loaded py python as follows:

- load the file
- activate the analysis
- make sure no results object is in the analysis
- make sure the results files are in place

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# actiate the analysis
import FemTools
fea = FemTools.FemTools()
fea.inp_file_name = '/tmp/Revolution_Mesh.inp'
fea.load_results()

Just did a few tests with other models, too. It really is "just" a bug in the solver control command. I will have a look.

Ahh your model has 51000 nodes. This is quit a lot for such an simple geometry. FreeCAD is quit slow because off such amount of data.

[kwahoo]

FreeCAD is quit slow because off such amount of data.

That's not a problem at all on modern hardware. But it can cause another issue, I think - error can accumulate due limited float/double precision and huge number of elements. Anyway, it was just a test case with default mesher setup.

[bernd]

PullRequest fix:
viewtopic.php?f=17&t=13494