How to increase the number of iterations for non linear analysis

Sanjay Dinker_21074

Hello,

 

I am trying to solve a simple cantilever problem. 
The force input is specified using TLOAD1 card. I have 13 data points in the force curve from 0 to 650N. 

During the non linear simulation, the solution converges after 21 iterations. At this stage, the force of around 50N is applied. 

I am trying to increase the number of iterations using NINC parameters in NLPARAM card. However, it is not working out. 

Is there a way to increase the number of iterations?

I have attached the .out file as well. 

If you want more information, let me know.

Thanks, 

Sanjay

Bending test ONLY PT.out

RobinsonFerrari

Hi Sanjay,

Your model is converging after 20 increments and 84 iterations.

NINC in NLPARM means the total force applied to your model will be split by NINC for the first increment. For instance, if you are using NINC=100 the first increment will be 0.01 (which means 6.5N in your case). You can also define DT directly as 0.01 instead.

In NLPARM you can define MAXITER (but not for the purpose you want, this is for convergence). You can add NLADAPT card, and specify DTMAX = 0.01, for instance. So, your model will have at least 100 increments (can be more if any cutback happens).

For using all the load applied be sure you are specifying the correct total value for 'time' and using TTERM accordingly in NLPARM as well. Since you are running in NLSTAT actually you can apply the load directly, without any TLOAD, and then NLADAPT will 'split' your curve.
Please let me know if works for you.

Thank you very much,