How to include both gravity and multi-point time domain dynamic loads in a loadstep?

Zaily

Hi, Guys!

Now I am using the HyperMesh and the Optistruct to simulink the load condition of the BIW. I need to create a loadstep including multi-point dynamic loads (in time history) and the influence of the gravity. I know to create a loadcollector and its card image is GRAV, and I know to multiple loadcollectors and its card image is tload1. In order to make multi-point forces act at the same time, I created a loadcolletor with dload card image for superposition. However， when creating the loadstep for transient direct analysis, there only was one loadcollector which can be selected here. so how to include both gravity and multi-point time domain dynamic loads in a loadstep?

Thanks for your reply!

Regard!

Adriano A. Koga

Hi @Zaily 

 

In your case, you will need to run 2 loadcases:

1) linear static one, with your GRAV as force

2) Transient analysis adding your DLOAD card as dynamic load, AND use the STATSUB(PRELOAD) to Add Gravity loadcase as your preload case. So gravity effects will be added as preload to your model, and it will include stiffening due to preload

 

I believe the help for OS discuss about preload effects.

Zaily

Adriano A. Koga_21884 said:

Hi @Zaily 

 

In your case, you will need to run 2 loadcases:

1) linear static one, with your GRAV as force

2) Transient analysis adding your DLOAD card as dynamic load, AND use the STATSUB(PRELOAD) to Add Gravity loadcase as your preload case. So gravity effects will be added as preload to your model, and it will include stiffening due to preload

 

I believe the help for OS discuss about preload effects.

Hi @Adriano A. Koga 

 

I got it. Thanks for your help!