conver dynamic analysis to quasi-static analysis

[beytut 1]

Hello;

 

I have .rad file for dynamic analysis. But I need to do quasi-static analysis with 5 mm/s constant velocity. How could I define time step. otherwise the solution may takes weeks. 

 

Could someone help me.

[Hyperman 286]

Hi,

 

You can simulate a quasi-static loading more computationally efficient by time scaling, which means applying the load more quickly in order to reduce the simulation time. However, the kinetic energy should be low (5-10%) compared to the internal energy for most of the simulation,  to minimize the inertial effects. You can check the energy fraction in Hypergraph by plotting both energies and using Vehicle safety tools (File-Load-Preference File) to divide curves (Math-Two Curves-Divide w/Zero). You can plot kinetic, internal, contact, hourglass and total energy in Hypergraph. Those variables are output by default and can be loaded in HG (file: runname_T01)>Global Variables>Y requests>MAG to plot.

 

The time-step can be increased by traditional mass scaling (/DT/NODA/CST) or advanced mass scaling (/DT/AMS). 

[simulation explicite 6]

Hi,

For mass scaling I would recommend you to go ahead with AMS, as this is a quasi static case. Make sure you properly select a time step for enforcing.

Finally ensure from T01 file that you have a very low/negligible KE for a quasi static analysis.

 

Best Regards,

.