Eigen value analysis

Numerical methods and mathematical models of Elmer
kevinarden
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Re: Eigen value analysis

Post by kevinarden »

Changing the tolerance cleared up the coincident nodes, not sure what the default tolerance is.

Merge "crackbeamf.msh";
Transfinite Curve {18, 19, 12, 13, 48, 54, 49, 55} = 17 Using Progression 1;
//+
Transfinite Curve {14, 15, 16, 11, 47, 51, 52, 50} = 3 Using Progression 1;
Geometry.Tolerance = 1e-5; // adjust value here for correct merge result
Coherence Mesh;
Rich_B
Posts: 421
Joined: 24 Aug 2009, 20:18

Re: Eigen value analysis

Post by Rich_B »

Hi,

Out of curiosity, how do you detect coincident nodes? By running Elmergrid with the merge command, or some other way?

Thanks, Rich.
kevinarden
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Re: Eigen value analysis

Post by kevinarden »

This time running ElmerGrid with the merge command. Salome also has a merge command. In the past I have plotted the deformed structure and you can usually see the disjointed parts flying away.
Sayan
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Re: Eigen value analysis

Post by Sayan »

Can I use this ElmerGrid command in windows? If so please tell me where to write this command..I use graphical interface of Elmer
kevinarden
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Re: Eigen value analysis

Post by kevinarden »

You can use ElmerGrid in windows. You have to open a command window and type in the command. The path depends on where you the program but the command is ElmerGrid.exe if you do a search.

If you have the path set to elmer as described in

https://www.nic.funet.fi/pub/sci/physic ... dElmer.pdf

than you can open a command window, chang to your working directory
type
ElmerGrid

and it will list the options.
Rich_B
Posts: 421
Joined: 24 Aug 2009, 20:18

Re: Eigen value analysis

Post by Rich_B »

Hi,

In the referenced document, GetStartedElmer.pdf, Section 7.1, 'Open a Command Prompt Anywhere' may be helpful for you, as it is Windows specific.

Rich.
Rich_B
Posts: 421
Joined: 24 Aug 2009, 20:18

Re: Eigen value analysis

Post by Rich_B »

Hi,

You can also run Elmergrid from within ElmerGUI, without using a command prompt.

Open ElmerGUI, load your .msh file using 'File -> Open'.

Then 'Mesh -> Configure', under 'Preferred generator' click the button for 'elmergrid'.

Look for the input box near the bottom labeled 'elmergrid' containing the String '-autoclean -relh 1.0'.

Add '-merge 1.e-5' to the above string, and click on 'Apply' to close the window.

To execute the elmergrid command, click on 'Mesh -> Remesh'

If you check 'Model -> Summary', before and after running 'Mesh -> Remesh', you will see the number of nodes decreases after the elmergrid remesh operation.

Give it a try and let us know what you find.

Thanks, Rich.
Sayan
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Joined: 06 Dec 2020, 12:44
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Re: Eigen value analysis

Post by Sayan »

Hiii,
Thank you...Last detailed process really helped me a lot to solve this matter...Thank you so much....
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