How to provide base excitation 1G load in Direct Frequency Response Analysis?

Jegan cae

I am doing a simple FRA of cantilever beam.

In SPCD load collector I included the Gravity in vertical direction.

The simulation is solving, but base motion (where the beam is constrained) is not observed.

Request members support.

Thanks,

Jegan

Xiaolei

Hi Jegan,

For modal frequency response analysis, we can use PARAM,ENFMOTN,REL to request relative output. 

https://help.altair.com/hwsolvers/os/topics/solvers/os/param_enfmotn_bulk_r.htm

 

But for direct method, it's not supported. 

So I would suggest using modal method if possible. 

 

Thanks. 

Xiaolei

Jegan cae

Xiaolei Song_21874 said:

Hi Jegan,

For modal frequency response analysis, we can use PARAM,ENFMOTN,REL to request relative output. 

https://help.altair.com/hwsolvers/os/topics/solvers/os/param_enfmotn_bulk_r.htm

 

But for direct method, it's not supported. 

So I would suggest using modal method if possible. 

 

Thanks. 

Xiaolei

Hello Song,

Thanks for the suggestion.

I tried Modal based method with SPCD card (G load applied on BC node). Its working now.

Might have done some mistake in direct method I suppose.

Anyhow will try your approach as well.

Thanks.