Learning Forum

[merts]

Hello, in LS_DYNA i used a viscoelastic material and made a modal analysis. However i only get the natural frequencies(real part of the frequency). How can i obtain the loss factor value to see damping ( complex part of the frequency) ?

Thanks in advance...

[Erik Kostson]

 

Hi

What you are trying I am pretty sure is not possible.

If you want to carry out a frequency response analysis say using SSD_DIRECT on the structure (and using mode super position), then measure (physical modal test) the modal dampings and assign them say in the :

LCDAM:=Load Curve ID defining mode dependent modal damping coefficient .

Which is a field in the *FREQUENCY_DOMAIN_SSD_DIRECT.

All the best

 

Erik