How to output element stiffness matrix to ASCII file in Optistruct

Anoop_20407

Hello everyone,

I’m beginner in use Optistruct and currently working on solving a static linear elastic problem. I’ve been trying to find a way to output the element stiffness matrix to a ASCII result file. Could someone please guide me on whether this is possible and, if so, provide instructions on how to achieve this?

Your assistance would be greatly appreciated.

Thank you in advance!

Anoop 

RobinsonFerrari

Hi Anoop,

Please try using the OUTPUT,MATRIX card (OUTPUT,MATRIX,REDUCED if reduced format is desired) to obtain the mass and stiffness matrices in ASCII format.

Thank you very much,

Robinson

RobinsonFerrari

Hi Anoop,

Please try using the OUTPUT,MATRIX card (OUTPUT,MATRIX,REDUCED if reduced format is desired) to obtain the mass and stiffness matrices in ASCII format.

Thank you very much,

Robinson

RobinsonFerrari

Robinson Ferrari_20451 said:

Hi Anoop,

Please try using the OUTPUT,MATRIX card (OUTPUT,MATRIX,REDUCED if reduced format is desired) to obtain the mass and stiffness matrices in ASCII format.

Thank you very much,

Robinson

https://help.altair.com/hwsolvers/os/topics/solvers/os/output_io_r.htm?zoom_highlight=output+matrxi

Anoop_20407

Thank you @Robinson Ferrari, your suggestion worked.

Pedro_Millan

Robinson Ferrari_20451 said:

Hi Anoop,

Please try using the OUTPUT,MATRIX card (OUTPUT,MATRIX,REDUCED if reduced format is desired) to obtain the mass and stiffness matrices in ASCII format.

Thank you very much,

Robinson

Dear Robinson,

 

I am using, successfully, the OUTPUT,MATRIX,FULL,SPARSE to output the stiffness and mass matrices, however, when it comes to the mass matrix, it omits the rotational inertia of the nodes that have 6DoF (corresponding to shell elements). Do you have any idea why this is happening and/or how to solve it? 

Thank you very much.

 

Best regards,

Pedro Millan