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APDL Number of Mode Shapes

APDL Number of Mode Shapes

APDL Number of Mode Shapes

(OP)
I'm running a modal analysis on a rotor with "a lot" of blades. Hence there are a to of mode shapes. Unfortunately it is impossible (Due to weird geometry) to make a simple cyclic model. So what I'm trying to do is run a modal analysis, up to maybe 13000 Hz and gather the z deflection of each blade (If we are dealing in cylindrical coordinates, which happens to be X in my current model. You'll see in the code below) as well as its relative location. I'm no APDL expert so this is the code I've run

CODE -->

ANTYPE=MODAL
ALLSEL
CMSEL,r,PointsAll


*DO,i,1,4,1
SET,,1
/output,i,txt
PRNSOL,U,X
NLIST
/output,trash,txt
*ENDDO 
where PointsAll is a named selection for the tip of each blade.

Some of the code may not even be nesecary but it seems to work and I'm afraid touching it will break it further. Obvious reasons why this code will not work is the output file name does not change in the DO loop. Also there will be much more modes than just 4. Im asking if anyone knows a command I could replace 4 with, that gives the max number of mode shapes available? something like

CODE

finalmode = MODE,LIST

*Do,i,1,finalmode,1 

So to recap. How do I change the /output,NAME,txt in a DO loop and haw do I set the DO loop to run the max number of modes available.

Any help on this subject would be very much appreciated. And to clarify, I'm pretty decent using Python code so the rest of the analysis was to be done using Python.

RE: APDL Number of Mode Shapes

(OP)
Sorry, the

CODE

set,,1 
is actually

CODE

set,,i 
inside the DO loop.

RE: APDL Number of Mode Shapes

Lets say you had 4 blades, component names blade1, blade2, etc. Then do this:

*do,bladeno,1,4

cmsel,s,blade%bladeno%

/output,blade%bladeno%,txt

*enddo

Rick Fischer
Principal Engineer
Argonne National Laboratory

RE: APDL Number of Mode Shapes

(OP)

Quote (rickfischer51)

Lets say you had 4 blades, component names blade1, blade2, etc. Then do this:

*do,bladeno,1,4

cmsel,s,blade%bladeno%

/output,blade%bladeno%,txt

*enddo

You are a genious. The variable encased with "%" signs works like a charm.

Thanks for the help(Although it was most likely obvious for the more experienced user) and I'll consider this case closed. No for some Python action

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