ANSYS Workbench: How to get SEPC? 1

[agestrada]

Hi,

I've been trying without success to obtain the structural error (global) in Ansys Workbench for a very simple model. Using the APDL command for the SEPC doesn't work as it says that SEPC is not available.

Any ideas?

Many thanks,

 

[petb]

Hi

Either in the analysis settings branch or in the solution branch, there is an option to set your requested output items, play with those settings and see if it helps. I'm not at the computer now so can't give any closer details.
Hope this helps
/petb

 

[agestrada]

Hi,

Thanks for your interest but I can't find that option in the GUI. As far as I understand, the only way is to run the APDL command PRERR using an object, but it gives me the error I mentioned before.

Best,

 

[petb]

Hi,

I had another look at this. Make sure to unselect non-structural elements like surface-elements before trying to get the PRERR-item, also this command need the graphics from an element-plot to work. This will work in the /graphics,full-mode only. The command snippet below will work for a shell model with 181-type elements. It's likely easy to adjust for your needs, depending on your APDL-knowledge of course.

[pre]
/post1

! enter the post processor​

set,first

! first result set​

esel,S,ename,,181

! select only your structural elements​

/GRAPHICS, FULL

! Turn on full graphics​

eplot ! plot elements[/indent]

*get,U,PRERR,0,SENSM

! get the error energy of the selected elements​

*get,e,PRERR,0,SERSM

! get the strain energy of the selected energy​

MY_SEPC=100*SQRT(e/(e+U))

! normalize the energy error against the strain energy​

! N.B keep the MY_-prefix to force Mechanical to put the​

! result in the Results cell of the Details view of your Command-snippet​

PRERR

! Put the SEPC in the output-file, now compare the calculated MY_SEPC to this to check that our calculated value is correct.​

allsel

! Select everything so you don't F*** up subsequent results in the Solution branch​

finish

! Exit /post1 nicely​

[/pre]

Hope this helps

/petb

 

[petb]

Forgot to mention something, the reason i used /graphics, full and eplot was to be able to use PRERR. Now as you see if you run the snippet above, you can calculate it yourself using the errror energy and the strain energy. So the snippen can be shortened to (comments removed):

[pre]
/post1
set,first
esel,s,ename,,181
*get,U,PRERR,0,SENSM
*get,e,PRERR,0,SERSM
MY_SEPC=100*SQRT(e/(e+U))
allsel
finish
[/pre]

HTH

/Petb