Hii Team,
I have modelled one beam with 3 blocks together and analysed to extract natural frequency values. But the results are not correct. Can anyone please help me to solve this issue??
Eigen value analysis
Eigen value analysis
- Attachments
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- crackbeam.msh
- (117.62 KiB) Downloaded 135 times
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- crackbeam.geo
- (51 Bytes) Downloaded 138 times
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- case.sif
- (1.63 KiB) Downloaded 145 times
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Re: Eigen value analysis
The model has coincident nodes and therefor the three blocks are separate independent bodies. Was this the intent?
Re: Eigen value analysis
The model will have 3 bodies with different properties for further analysis. But to start with I wanted to find out the natural frequency of the system as a whole with same property.
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Re: Eigen value analysis
There is a difference between three independent bodies not attached to each other and three bodies attached but with different properties. Currently you have three independent bodies not attached to each other.
Re: Eigen value analysis
It should be an attached body in my case..I have also used common edge of different parts to join them node to node using FreeCad... In this way previously I got an attached body with modification of geo file where mesh has been merged at co-incident points.. For this case if it's showing different bodies which are not connected, how can I join them to get a connected body?
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Re: Eigen value analysis
One way is to use ElmerGrid to convert the mesh and merge the coincident nodes.
ElmerGrid 14 2 cracked.msh -merge 1.e-8
Another whay is to use the coherence command in gmsh to merge the coincident points prior to exporting he mesh,
ElmerGrid 14 2 cracked.msh -merge 1.e-8
Another whay is to use the coherence command in gmsh to merge the coincident points prior to exporting he mesh,
Re: Eigen value analysis
Hiii,
Thank you... But if you look into my .geo file you can see I have used coherence mesh command before exporting to Elmer..You suggested me this earlier for another model..That time with this modification I got good result...But this time it's not working in this model..Don't know why..
Thank you... But if you look into my .geo file you can see I have used coherence mesh command before exporting to Elmer..You suggested me this earlier for another model..That time with this modification I got good result...But this time it's not working in this model..Don't know why..
Re: Eigen value analysis
Hi,
Looking at the contents of the .geo file, it looks questionable:
Let us know what you find out.
Rich.
Looking at the contents of the .geo file, it looks questionable:
Try adding the Coherence command before generating the mesh that gets stored in 'crackbeam.msh'. Adding the Coherence command after the meshing operation has finished and has been written to file, may possibly be the issue.Merge "crackbeam.msh";
//+
//+
Coherence Mesh;
Let us know what you find out.
Rich.
Re: Eigen value analysis
Hii,
After generating .geo file while using Gmsh and before doing meshing I edited the .geo file and inserted the coherence command,..Then I create meshing and save and then export.. Following this I have got no improvement.. I am attaching my new .geo file with case.sif here..
After generating .geo file while using Gmsh and before doing meshing I edited the .geo file and inserted the coherence command,..Then I create meshing and save and then export.. Following this I have got no improvement.. I am attaching my new .geo file with case.sif here..
- Attachments
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- crackbeamf.msh
- (205.53 KiB) Downloaded 135 times
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- crackbeamf.geo
- (202 Bytes) Downloaded 129 times
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- crackbeamf.brep
- (32.02 KiB) Downloaded 129 times
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Re: Eigen value analysis
It still has coincident nodes. I am able to merge them with ElmerGrid.