Tackling time step problem
Hello everyone,
i had a question about time steps and i'm having some difficulties in tackling that problem. I'm running a simulation with a duration of 0.2s and i have checked the time steps for the different type of elements on Hyperworks. It is as follows:
Shells: 3.17e-16
Springs: 1.581e-6
The output of the simulation is either RUN KILLED: ENERFY ERROR LIMIT REACHED or RUN KILLED: TOTAL MASS ERROR. I've attached a screenshot of my output file to understand it better. I am not really understanding the message actually. Does it mean that interface ID 17 is causing a problem?
Interface 17 is a type 7 self contact and i've tried everything i know to prevent that failure. there are also no penetration when i checked. I tried increasing the gaps, increase/decreasing the stiffness as well but nothing seems to be working.
I tried using different methods for time steps (SHELL, NODA, INTER) but with Shell and Inter, i'm having a really large simulation time. The only thing that's running the simulation is DT/NODA/CST/0 with a timestep of 5e-7.
What i saw on the forum is, that DT/NODA/CST/0 adds masses to the nodes in order to keep a stable time step but hence leads to a mass error and energy error. how is it possible to control the mass being added, for it not to be too big?
It will be really helpful to me, if you could help me with that problem.
Thank you very much,
Umehr