LOAD PROP and PERIodic CAUChy

[Lukas_Poggenpohl]

Dear FEAP Forum,

I am currently trying to load an RVE with different deformations, sequentially. (E.g. first tension- then shear load as specified in the example attatched)

I am facing the problem, that the geometry is not loaded using PERIodic CAUChy. If I specify BCs via CDIS (Instead of PERIodic CAUChy), it works.

According to the O-File, load sets 1 and 2 are generated but the geometry is not loaded. (Warning for zero RHS.)

The example Input and Output files are attatched, I am using FEAP 8.4.

Thanks for the help and stay healthy,

Lukas Poggenpohl

[Prof. R.L. Taylor]

You have ELINK before the END of mesh command.   Thus, no linking is performed.  THe ver8.4 is known to have problems with load groups so it may not work,  I am not sure you can load two periodic cauchy definitons, check which one is used -- probably the last one.

[Lukas_Poggenpohl]

Dear Prof. Taylor,

the ELINk does work now. Thank you for the fast response.

As you expected, only the last CAUCHY is used (for both PROP commands). I now tried FEAP 8.5 which shows the same issue.

Is there a possibility, to circumvent/solve this problem?

Kind regards,

Lukas Poggenpohl

[Prof. R.L. Taylor]

It could be done.  It would require tracking where the arrays are used, adding a loop around them for the number that are defined and accumulating the result.  I am not sure how many changes are required -- it is something we would possibly do in a future release as it involves changes in multiple modules. 

You can do by starting with the inputs which will be done in 'pmesh.f' in ./program directory and follow all the uses of the arrays.  I suppose it would be necessaary to limit to a few arrays as my memory is that none are allocated.

[Xuannamdo-danang]

Dear Prof. Govindjee,

Thanks for your reply

I enclose 3 pictures showing nodes needed to be linked and an input file in which I used commands: LINK and PERIODIC. Could you please let me know whether I exactly followed your instructions?

Thank you so much

Sincerely yours,
Nam Do