[SOLVED]frequency analysis with multi materials

About the development of the FEM module/workbench.

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aszodi95
Posts: 7
Joined: Mon Jun 25, 2018 6:30 am

[SOLVED]frequency analysis with multi materials

Postby aszodi95 » Mon Jun 25, 2018 7:24 am

Hello,

I wanted to make a frequency analysis with freecad and calculix. First I made 5 cubes and then with "make compound" command I created one part.
1.PNG
1.PNG (57.87 KiB) Viewed 305 times
After this in FEM workbench I defined the materials - shorter sections 15CrNi6, the longer sections AlZn4 (the aim was to take mass points on a beam).
Then I gave a force and a constrain to the beam.
2.PNG
2.PNG (49.81 KiB) Viewed 305 times
Meshed it and tried to run calculix but it says the next error everytime. I tried it already with part unite (fusion) but the resolution was the same.
analysis_err.PNG
analysis_err.PNG (73.78 KiB) Viewed 305 times
So, my question is, what do I have to chance in this process to get the results?
And thank you, in advance, for your help/answer!
Attachments
freq_pentek_eslo.FCStd
(21.54 KiB) Downloaded 9 times
Last edited by aszodi95 on Mon Jun 25, 2018 1:32 pm, edited 1 time in total.
chrisb
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Re: frequency analysis with multi materials

Postby chrisb » Mon Jun 25, 2018 7:37 am

(moved to FEM forum)
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bernd
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Location: Zürich, Switzerland

Re: frequency analysis with multi materials

Postby bernd » Mon Jun 25, 2018 10:29 am

- use a BooleanFragment instead of a Compound
- assign your material to a volume not to a area
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bernd
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Re: frequency analysis with multi materials

Postby bernd » Mon Jun 25, 2018 10:56 am

find attaced an example ...

multi_mat_freq.FCStd
(543.44 KiB) Downloaded 23 times

multi_mat_freq.FCStd
(543.44 KiB) Downloaded 23 times

pic2.JPG
pic2.JPG (296.69 KiB) Viewed 270 times
Attachments
pic1.JPG
pic1.JPG (295.48 KiB) Viewed 270 times
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bernd
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Re: frequency analysis with multi materials

Postby bernd » Mon Jun 25, 2018 10:57 am

this may help too ... FEM_Shear_of_a_Composite_Block
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HarryvL
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Re: frequency analysis with multi materials

Postby HarryvL » Mon Jun 25, 2018 12:16 pm

aszodi95 wrote:
Mon Jun 25, 2018 7:24 am
Hello,

I wanted to make a frequency analysis with freecad and calculix. First I made 5 cubes and then with "make compound" command I created one part.

1.PNG

After this in FEM workbench I defined the materials - shorter sections 15CrNi6, the longer sections AlZn4 (the aim was to take mass points on a beam).
Then I gave a force and a constrain to the beam.

2.PNG

Meshed it and tried to run calculix but it says the next error everytime. I tried it already with part unite (fusion) but the resolution was the same.

analysis_err.PNG

So, my question is, what do I have to chance in this process to get the results?
And thank you, in advance, for your help/answer!
@aszodi95 from an engineering point of view, what behavior are you trying to model? For example, do you want to apply a harmonic load or shock load and see how the assembly vibrates?
aszodi95
Posts: 7
Joined: Mon Jun 25, 2018 6:30 am

Re: frequency analysis with multi materials

Postby aszodi95 » Mon Jun 25, 2018 12:17 pm

Thank you very much, for your help! :D
aszodi95
Posts: 7
Joined: Mon Jun 25, 2018 6:30 am

Re: frequency analysis with multi materials

Postby aszodi95 » Mon Jun 25, 2018 12:34 pm

#HarryvL

This is now just a practice, for me. In the future I have to analyse aeroelastic fluttering on an airplane's wing, and the simplified model will be a beam model. And the shorter sections with the higher density would be the mass points. So now I just tried to build a model, which is constructed from different materials.