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Large Deformation Analysis(LDA)

ilyachaban
14-Alexandrite

Large Deformation Analysis(LDA)

Hello, I'm new into creo simulate LDA and i want to know how if there is any good practices using this feature.

When I was trying to set analysis it wasn't converging at all but using a small bit other boundary conditions it was converging in 15minutes. Every and each time model was stable and doesn't have to have problems with convergence. I even connected each part to another using simple springs with small stifness. Material is linear. 

Are there any good practices how to model for LDA?

1 REPLY 1
ilyachaban
14-Alexandrite
(To:ilyachaban)

Last successfull simulations was done using this method: 

1) choose time steps you are interested in

Example:

  1. 0.0001
  2. 0.1
  3. 0.2
  4. 0.5
  5. 0.7
  6. 0.9
  7. 1

2) Find step where it can't converge

Example from *.pas file: 

contact poor (nonmonotonic) convergence
newton. total Stiffness Evaluations: 257
newton. total Residual Evaluations: 650

Load Factor: 0.775
***resetting displacement to last cnv soln
Detected that stiffness evaluations are not much slower than residual for this load step.
Using full Newton nonlinear solution.

 

3) Create additional step to insure convergence

Example new steps:

  1. 0.0001
  2. 0.1
  3. 0.2
  4. 0.5
  5. 0.7
  6. 0.85
  7. 0.9
  8. 1

There is no known way how to correctly choose new steps(or I don't know this way)

 

One more problem of this method is that i have to start all over again if i add new step. Even if previously simulated steps converged succesfully. I didn't find method how to save successfull steps. each time there is a need to start simulation from it's first step and sometimes it takes very long time.

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