Selecting all nodes in an area

[vidiii]

Hi,

I'm trying to select all nodes of an area that is defined. I can't use nsel (because ANSYS crashes then), I must use FITEM commands.

Example (from another work):

! Defining that the nodes on upper electrodes are coupeld considering the voltage.
! ANSYS crashed when the more easy command nsel was used
FLST,4,325,1,ORDE,7
FITEM,4,4580
FITEM,4,4582
FITEM,4,-4599
FITEM,4,4626
FITEM,4,-4639
FITEM,4,4662
FITEM,4,-4953
CP,1,VOLT,P51X

! The same for the nodes on the lower electrode
FLST,4,325,1,ORDE,7
FITEM,4,3860
FITEM,4,3862
FITEM,4,-3879
FITEM,4,3906
FITEM,4,-3919
FITEM,4,3942
FITEM,4,-4233
CP,2,VOLT,P51X

How can I select those nodes like the author did via a GUI command? (FITEM and FLST) I could write APDL for this problem, but I think it's possible to solve this in a fast way.

Could somebody please help me. Thanks in advance!

Kindest regards,
mab

 

[DanRail]

I'm not really familiar with the FITEM commands, but the documentation shows these as commands generated in the log file from performing list commands with picking (elis,p or nlis,p).

I opened a simple model and no FITEM commands were generated in the log file for an esel,r,p command, but FITEM commands were generated for performing an elis,p command. These would suggest that FITEM commands are used for listing but not for selecting. If you're sure it can be made to work, then I'll defer to your knowledge of the FITEM commands.

Alternatively, you can use the NSLA command (unless this also causes a crash).

Select the area in question, then use the NSLA command to select only the nodes contained within the selected area(s).

Hope this helps.

 

[vidiii]

The FITEM command identifies items chosen by a picking operation (GUI). However I don't know how the author did the picking operation. I can pick planes, nodes, keypoints, ... but not saying to select all nodes on a plane. Do you have an idea?

Thanks for your reply

 

[vidiii]

It seems that ANSYS does not crash like the author claimed.
I used this:

NSEL,S,LOC,Z,h_b/2+h_p,h_b/2+h_p
CP,1,VOLT,ALL

works great, no crash.

Cheers.

 

[DanRail]

If you know the number for the area in question I'd still use NSLA.

For example if the area in question is area #12:

ASEL,S,AREA,,12
NSLA,S,1 (or 0, depending if you want all nodes in the area or only interior nodes).

That way you don't have to know the geometry.

-Dan