FEAP User Forum

FEAP => Input File Issues => Topic started by: BSFEAP on February 03, 2016, 09:13:35 AM

Title: thermo-mechanical +boundary conditions
Post by: BSFEAP on February 03, 2016, 09:13:35 AM

Dear All,

Using the FEAP standard element to run thermo-mechanical coupling.  Attachments are two inputs files
(1) staggered way with partition command
(2) monolithic way

I prescribe mechanical boundary conditions by using CBOU and CSUR.  And setting up proportional load with CPRO.
Monolithic way works well. However, with partition command, the results looks strange.

If I use partition command for solving coupled problem, how can i correctly use commands like CBOU, CSUR and CPRO.

Thanks  lot.

Title: Re: thermo-mechanical +boundary conditions
Post by: Prof. R.L. Taylor on February 03, 2016, 10:51:12 AM

Very good question.

Boundary conditions should apply for the entire problem.  Thus, if a partition activates certain degrees of freedom the corresponding b.c. conditions apply.

Similarly, CSUR generates sets of forces that apply to specified dofs; again if the dof is active the forces generated apply.

So, you currently cannot associate certain b.c. with a specific partition; and similarly for the CSUR.

Now the question remains: Is this the way you need it?

Title: Re: thermo-mechanical +boundary conditions
Post by: BSFEAP on February 03, 2016, 12:36:40 PM

Dear Prof. Taylor,
Thanks a lot for your quick reply. Yes, we do need it. 
(1) experimental data are associated with coordinates
(2) our problem need staggered scheme, otherwise, it is hard to converge.