Complex Eigen Mode Analysis

Debarshi

Hi everyone,

As shown in the picture, I have a pulley belt system (green pulley and blue marked belt). There is a noise issue in the system and so I would like to implement a complex eigen mode analysis for check if there is any unstable mode or not, as unstable modes mostly contribute to the noise.

I have refered to OS-T: 1370 Complex Eigenvalue Analysis of a Reduced Brake System, there it has been mentioned about a DMIG.pch file. I am not able to understand it properly. Please elaborate about it and basically what would I need for my model? What my DMIG.pch file should contain?

Thanks and regards,

Debarshi

 

 

 

pulley_belt.PNG

Kory

Hello,

I noticed this question never received any reply. Just in case it is still relevant, here is my best answer for you.

The DMIG.pch file contains information about any superelements in your model. You can use this as part of your input file or just link the grid points together using K2GG=KAAX.

Essentially, it is holding the stiffness matrices in a reduced form. 

The only extra step on your end should be 1 of 2 options:

1) copy/paste the info into your input file

2) Activate the .pch file within HM before running the job. You'll need to provide a link to the correct directory as well as a definition like the one I mentioned above.

 

Feel free to reach out directly if you have further questions. Happy to help!