Hi, you may refer to the scripting module for ABAQUS where there is higher flexibility for modelling. In your case, node selection can be automated by scripting. Also regarding the modifications to the input file, ABAQUS will ignore or produce warnings or errors if the syntax is not correct (However please make sure if you were submitting the input file as the job and not the model - or else the input file is generated once more by overriding your changes).

All the best!

Dear Harikrishnan K. Sreekumar,

Thank you for your reply. I have solved the problem by editing the .inp file correctly.

However, your suggestions are really appreciated.

Regards,

Dipaloke

As a user/trainer I would highly discourage the manual editing of the input file unless it is absolutely necessary. Simply because it is almost impossible to track who changed and what in the file. There are usually many ways you can solve the problems within CAE.

Applying different loads to many nodes can be usually done easily, taking multiple approaches, depending on how the load change:

1) Use an analytical field to describe the loads to be applied as an analytical function of coordinates for example

2) Use discrete fields to map your values to the nodes. This is good if you don't have an analytical expression, for example loads coming from another numerical software.

3) Record a macro when you apply one load, then modify the python script to iterate over a set of nodes. This is the most flexible as you can literally apply anything anywhere.

Regarding element activation/deactivation you just need to ensure the loads are activated only when the nodes are active as well.

Also keep in mind, that whatever load you apply it will be turned into nodal forces by the software before analysis. So concentrated nodal forces have the same effect as applying a pressure/traction or any other type of load. Maybe it is easier to apply varying pressure over a surface than defining independent CFORCE on the nodes.

Unless you used it before (and like it :) ) I would stay clear of subroutines. They provide amazing flexibility but have a super steep learning curve. Also, unless the loads depend on the calculated results (so essentially a control/feedback loop) they can most of the time be done with some other mechanism.

I hope this brief reply was helpful. Good luck!

Dear David Sziroczak,

Thank you for your detail reply. You have suggested me three possible options for the solutions of my problem. Among them I have tried to use the option 1 already. But, my loads are not correlated with any analytical function.

However, I am very much interested to use the option 3 which you (and also Mr. Harikrishnan K. Sreekumar ) have suggested to me. Therefore, kindly give me some details where I can learn about this technique to solve my problem as my knowledge about editing python script is very limited. If possible please send me some example python code in my problem.

Thank you,

Regards,

Dipaloke

Dear Dipaloke Majumder ,

fortunately, python is pretty easy to learn, you can find good training material online for free. For example https://www.learnpython.org/ lets you actually type in code and try out scripts online without installing anything. I would recommend to get some familiarity with the code itself before taking the next step.

Regarding how to write the actual script, and examples once you got your head around the language, the only difficulty is understanding the Abaqus/CAE object models. Fortunately, you have help available. First, as I mentioned, you can start recording a macro in CAE. While you are recording, any command you do (including rotating the screen, etc.) are recorded in a macro file. If you select "work" folder at the beginning, then your macros file will be saved in your work folder, which is by default C:\Temp, so you can find it easily. So what you should do is apply a concentrated force somewhere, and the computer will write down the appropriate python line to achieve that.

Once you stop recording, when you open the file, you can see how is the actual syntax for applying the load at the correct node in the correct step and with the correct force components. The next step would be to extract the set of nodes you wish to apply those loads to and iterate over all the nodes, for example with a for loop. If you set a BC on a set of nodes while recording the macro, I believe CAE will write the line of code showing you how to return the set object to you.

Also, you don't even need to record a macro, as anything you do in CAE will be written into the journal/replay file, so you can always extract the python codes from there. Just don't forget to include all the import statements at the beginning of the script so you have the CAE namespace.

If you need specifics on how to access some CAE object, and more description of the scripting functionality, you can look up the Scripting manual and the Scripting Reference manual.

Dear David Sziroczak and dear Harikrishnan K. Sreekumar,

Thank you for your detail reply. It is really helpful for me. I have solved the issue. I am also sorry for late reply.

Regards,

Dipaloke

Dear Dipaloke Majumder ,

well done, that is excellent news! I'm happy that the recommendations were useful afterall.

Best regards,

David