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ankushaggarwal
05-02-2014, 09:43 AM
Hello,

I am using shell model with coupled solid mixture. Is there a way I can enforce the plane stress condition?

Theoretically, plane stress condition can be enforced combined with incompressibility condition (normal stress=0 + Jacobian=1 => the pressure Lagrange multiplier). Is there any way this can be accomplished in FEBio?

Another question on a slightly different topic. I am running FEBio on a cluster in a silent mode (-silent) within an optimization loop. The console class which sets the terminal title is causing a lot of undesired output in the log file which makes it hard to read (an example below). Is there any way, the setting of terminal title can be turned off, since it is not of use while running jobs in a queue anyways?

Thanks,
Ankush.

Example of FEBio log file in my optimization loop when run on a cluster:
----------------------------------------
Iteration number: 0 starting
ESC]0;(0%) try-job-new2.feb - FEBio 2.0.0 ^GESC]0;(0%) try-job-new1.feb - FEBio 2.0.0 ^GESC]0;(0%) try-job-new0.feb - FEBio 2.0.0 ^GESC]0;(3%) try-job-new1.feb - FEBio 2.0.0 ^GESC]0;(3%) try-job-new0.feb - FEBio 2.0.0 ^GESC]0;(7%) try-job-new1.feb - FEBio 2.0.0 ^GESC]0;(7%) try-job-new0.feb - FEBio 2.0.0 ^GESC]0;(11%) try-job-new1.feb - FEBio 2.0.0 ^GESC]0;(11%) try-job-new0.feb - FEBio 2.0.0 ^GESC]0;(15%) try-job-new1.feb - FEBio 2.0.0 ^GESC]0;(15%) try-job-new0.feb - FEBio 2.0.0 ^GESC]0;(19%) try-job-new1.feb - FEBio 2.0.0 ^GESC]0;(19%) try-job-new0.feb - FEBio 2.0.0 ^GESC]0;(23%) try-job-new1.feb - FEBio 2.0.0 ^GESC]0;(1%) try-job-new2.feb - FEBio 2.0.0 ^GESC]0;(23%) try-job-new0.feb - FEBio 2.0.0 ^GESC]0;(27%) try-job-new1.feb - FEBio 2.0.0 ^GESC]0;(5%) try-job-new2.feb - FEBio 2.0.0 ^GESC]0;(27%) try-job-new0.feb - FEBio 2.0.0 ^GESC]0;(31%) try-job-new1.feb - FEBio 2.0.0 ^GESC]0;(9%) try-job-new2.feb - FEBio 2.0.0 ^GESC]0;(35%) try-job-new1.feb - FEBio 2.0.0 ^GESC]0;(31%) try-job-new0.feb - FEBio 2.0.0 ^GESC]0;(13%) try-job-new2.feb - FEBio 2.0.0 ^GESC]0;(39%) try-job-new1.feb - FEBio 2.0.0 ^GESC]0;(35%) try-job-new0.feb - FEBio 2.0.0 ^GESC]0;(17%) try-job-new2.feb - FEBio 2.0.0 ^GESC]0;(43%) try-job-new1.feb - FEBio 2.0.0 ^GESC]0;(39%) try-job-new0.feb - FEBio 2.0.0 ^GESC]0;(21%) try-job-new2.feb - FEBio 2.0.0 ^GESC]0;(47%) try-job-new1.feb - FEBio 2.0.0 ^GESC]0;(43%) try-job-new0.feb - FEBio 2.0.0 ^GESC]0;(51%) try-job-new1.feb - FEBio 2.0.0 ^GESC]0;(25%) try-job-new2.feb - FEBio 2.0.0 ^GESC]0;(47%) try-job-new0.feb - FEBio 2.0.0 ^GESC]0;(55%) try-job-new1.feb - FEBio 2.0.0 ^GESC]0;(29%) try-job-new2.feb - FEBio 2.0.0 ^GESC]0;(51%) try-job-new0.feb - FEBio 2.0.0 ^GESC]0;(59%) try-job-new1.feb - FEBio 2.0.0 ^GESC]0;(55%) try-job-new0.feb - FEBio 2.0.0 ^GESC]0;(33%) try-job-new2.feb - FEBio 2.0.0 ^GESC]0;(63%) try-job-new1.feb - FEBio 2.0.0 ^GESC]0;(59%) try-job-new0.feb - FEBio 2.0.0 ^GESC]0;(37%) try-job-new2.feb - FEBio 2.0.0 ^GESC]0;(67%) try-job-new1.feb - FEBio 2.0.0 ^GESC]0;(63%) try-job-new0.feb - FEBio 2.0.0 ^GESC]0;(41%) try-job-new2.feb - FEBio 2.0.0 ^GESC]0;(71%) try-job-new1.feb - FEBio 2.0.0 ^GESC]0;(67%) try-job-new0.feb - FEBio 2.0.0 ^GESC]0;(45%) try-job-new2.feb - FEBio 2.0.0 ^GESC]0;(75%) try-job-new1.feb - FEBio 2.0.0 ^GESC]0;(71%) try-job-new0.feb - FEBio 2.0.0 ^GESC]0;(49%) try-job-new2.feb - FEBio 2.0.0 ^GESC]0;(79%) try-job-new1.feb - FEBio 2.0.0 ^GESC]0;(75%) try-job-new0.feb - FEBio 2.0.0 ^GESC]0;(83%) try-job-new1.feb - FEBio 2.0.0 ^GESC]0;(53%) try-job-new2.feb - FEBio 2.0.0 ^GESC]0;(79%) try-job-new0.feb - FEBio 2.0.0 ^GESC]0;(87%) try-job-new1.feb - FEBio 2.0.0 ^GESC]0;(57%) try-job-new2.feb - FEBio 2.0.0 ^GESC]0;(83%) try-job-new0.feb - FEBio 2.0.0 ^GESC]0;(91%) try-job-new1.feb - FEBio 2.0.0 ^GESC]0;(61%) try-job-new2.feb - FEBio 2.0.0 ^GESC]0;(95%) try-job-new1.feb - FEBio 2.0.0 ^GESC]0;(87%) try-job-new0.feb - FEBio 2.0.0 ^GESC]0;(65%) try-job-new2.feb - FEBio 2.0.0 ^GESC]0;(91%) try-job-new0.feb - FEBio 2.0.0 ^GESC]0;(99%) try-job-new1.feb - FEBio 2.0.0 ^GESC]0;(69%) try-job-new2.feb - FEBio 2.0.0 ^GESC]0;(95%) try-job-new0.feb - FEBio 2.0.0 ^GESC]0;(100%) try-job-new1.feb - FEBio 2.0.0 ^GSubmitting the job to FEBio
Job completed in 8.57 minutes
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maas
05-05-2014, 03:09 PM
Hi Ankush,

There is currently no special formulation available for incompressible shells. You can try increasing your bulk modulus, but you most likely will get element locking.

The console class doesn't write any text to the log file, so I'm not sure how this got into the log file. Or do you mean, it's writing this text to the screen output? In any case, I will add an option to suppress the title update.

Cheers,

Steve

ankushaggarwal
05-05-2014, 03:39 PM
Hi Steve,

Thanks for your reply. Is there a way to explicitly enforce plane stress condition in shells (although compressible)?

Sorry for the confusion, this is not the FEBio log file but the job queue log file. When running FEBio on cluster, it runs through job queue and since it cannot set the terminal title, it prints it out (as the above example). If you can add an option to suppress the title update, that would be great.

Thanks,
Ankush.

maas
05-05-2014, 04:30 PM
Hi Ankush,

There is not, but I don't think you need to enforce this explicitly as this is usually incorporated in the shell formulation. FEBio's shell formulation does not incorporate it directly, but I think it's formulation should behave similarly (again, I think). Are you running into any issues?

Steve

ankushaggarwal
05-05-2014, 04:52 PM
OK. No issues as of now, I got a simulation working but wanted to make sure that I am implementing everything in the right way. I think I agree with you that one probably does not need to enforce it explicitly, balance of forces should result in plane stress. In incompressible case, it would be different though.

Thanks for clarifying.
Ankush.