I am struggling with the following problem:
I am trying to model, using sol 601/106 the flattening of a pipe (see the attached file pipe.jpg ). The problem is that although I am increassing the time interval of the applied displacement, I always get practically the same results (see file pipe2.jpg). It is like NX stops in the same place. I also mention that I do not receive any message about errors!
I think you have to describe something more of our problem, because if something is wrong, the question ist, what do you want to do, what is the way you choose to solve our problem, what kind of results do you expect and THEN what is wrong, therefore here some questions to help to encircle the problem.
1. What ist the enforced displacement or load, do yout put on your model?
2. What kind of solution sheme did you use?
- Case Control => Strategy parameters: default, ATS, TLA, TLA-S
3. Which way to define the time characterisitc did you choose?
- Case Control => Time Step definition: TimeSteps
4. What is the method to define your time dependent enforced displacements?
5. Do you expect large deformations or strains and did you activate the right parameter option?
6. What kind of contact parameter did you select?
7. Did you already tried to solve it in SOL101?
May be it helps yourself to get more information about your problem.
Sorry for replying so late.
Regarding the enforced displacement and the time table, if I correctly understood, you suggested that the table acts like a multiplyer of a displacement. I have used Enforced displacement (see Enforced1 and 2) and it seems that the table provides absolute values (expressed in mm). Am I wrong?
Apart from that, when running the analysis, I am using the general settings:
- Number of time steps:10000
- Time increment:0.01
- Skip factor for output:1
With these, using the following settings for the enforced displacements, I got:
1. Time 0,0;100,1 -> max displacement: .01
2. Time 0,0;100,5 -> max displacement: .05
3. Time 0,0;10,1 -> max displacement: .1
4. Time 0,0;10,5 -> max displacement: .5
With - Number of time steps:1000 (the rest unchanged) and Time 0,0;10,5 -> max displacement was also: .5
I a confused!
many thanks in advance
PS. I have also attached the f06 file for the last case
With your help I managed to get a solution. Thank you. Now I have two other questions:
1. Is it possible to define some sort of a sensor to stop the analysis when the stress in a certain point (node) reached a certain value?
2. How can I control the way elements where the stress exceeds the strength limit behave?
Many thanks in advance
that are two very interesting questions but I 'm not able to answer in a meaningful way.
I suggest you post these questions as a new thread.
As a hint for q2, may be it helps:
To control the nonlinear behaviour of elements you can set different yielt function criterias i.g. in description for MATS1. May be its what you look for.
There is no ability to stop a SOL 601 solution based on a stress limit.
By default, multilinear plastic material properties defined via MATS1/TABLES1 will be extrapolated beyond the last point defined in the table. If you set XTCURVE=1 on NXSTRAT, elements exceeding the last strain value in the table data will be considered ruptured and will be removed from the solution.