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would you use implicit or explicit for this?

would you use implicit or explicit for this?

would you use implicit or explicit for this?

(OP)
A whipping motion of a thin sheet. There is a wave that moves through the sheet then I am getting errors with individual elements lighting up and then it aborts.

I'm using a quasi static implicit analysis with no damping as its not actually a sheet and it would likely be heavily damped as the real life scenario is submerged in fluid.

Bit of a strange one I know but any help is appreciated!

RE: would you use implicit or explicit for this?

I would have gone with explicit.

RE: would you use implicit or explicit for this?

(OP)
can you give me your reasons?

RE: would you use implicit or explicit for this?

If inertia is involved Explicit is a good place to be. Implicit dynamics could also work. It's largely dependent on your time scale, model geometry and materials.

You may want to consider modeling the fluid either with:

CEL (coupled eulerian lagrangian) which is great for mud or putty
or
FSI (fluid structure interaction) where deformable bodies are interacting with fluids such as water or air.

I hope this helps.

Thank you.

Rob Stupplebeen
OptimalDevice.com
My Personal WP

RE: would you use implicit or explicit for this?

(OP)
I'm using a quasi static application to negate the inertia. The simulation is running over a few seconds,my impression is that a quasi static step would not take Intl account inertia but my model exhibits what appears to be inertia (I'm assuming some form of kinetic energy) hence trying to maybe damp it out

RE: would you use implicit or explicit for this?

Have you tried running an explicit analysis?

If you have a wave like phenomena I dont see why you would not want to use explicit, after all the waves motion will be time dependent.

RE: would you use implicit or explicit for this?

(OP)
I'm using a dynamic step so the solver is still taking the time dependency into account, unless I am missing something?

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