Termination time for geometric non-linear static analysis (TTERM)

Altair Forum User

Hello

I was doing geometric nonlinear analysis of flat plate. I would like to know deformation of plate under constant pressure loading in static. how much termination time should I mention as TTERM (Simulation time). I observed that increasing in time increases deformation. how much time shall I provide to know static deformation.

Thanks

Altair Forum User

Hello

I was doing geometric nonlinear analysis of flat plate. I would like to know deformation of plate under constant pressure loading in static. how much termination time should I mention as TTERM (Simulation time). I observed that increasing in time increases deformation. how much time shall I provide to know static deformation.

Thanks

k.u=f, so static means the state in the static equilibrium point. you should keep increasing the time until you find that point.

Altair Forum User

Hi,

if your load isn't time dependet, then don't use NLOADs or TTERM.

You can force a normal nonlinear solution (NLGEOM) and get the static equilibrium, including all nonlinear effects (in your case i think it is large deformation only).

Regards,

Mario

Altair Forum User

TTERM can also be used as a convenient termination time that splits up an applied force or displacement load proportional to the time of the solution. Also, TTERM is divided by NINC in the NLPARM card to generate the initial timestep.

If your plate keeps deflecting by increasing TTERM, then you need to go into your solution and find out if the applied force or displacement is reaching its defined value (SPCFORCE or ELFORCE). My guess is that it is not and as MARIO suggested, the displacement is creating strains greater than 5% and you need to use large displacement as the solution type.