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CMS Superelement Harmonic Analysis

Fig 1: Project Schematic

With the release of Mechanical 19.2, substructuring is now available for Modal & Rigid Dynamics without scripting. That just made my earlier post on CMS outdated! Note that there is still a key limitation where Generation and Expansion Pass must be performed on your local machine.

To get ahead of the game a bit, here is a way to do Harmonic Analysis extending on previous work. (Please go through that before this post). Some points of note:
  1. The method of merging the CMS and non-CMS models together into System C is the same.
  2. All files related to the superelement has to be copied over to the solver file directory as before.
  3. Modal analysis need not be performed first as the example here uses Full Method instead of Modal Superposition for simplicity. 
  4. The script expands the responses the same way as Modal Analysis does so the script will look familiar.
Additional Resources:
Example: Harmonic Response to Unbalanced Force using CMS (Link)
Example: Modal and Harmonic Analyses of an Automotive Suspension Assembly Using CMS (Link)

Command Snippet for Combined Analysis D
!!!!! Save full model
fini
/filnam, full
save

!!!!! perform use pass solution
/filnam, use
/prep7
! Deletes body to be replaced by cms element
alls
cmsel, s, BODY1_CMS_PART_  ! ** part named selection for deletion **     
nsle
cmsel,u, interA_CMS_PART_  ! ** don't delete interface nodes **
edele, all
ndele, all

alls
*get, etmax, etyp, 0, num, max
et, etmax+1, 50         ! define substructure element type 
type, etmax+1
mat, 1
se, myse                ! define substructure element
fini
save

/solu                   ! uses exisitng settings
solve
fini

!!!!! expand the solution for viewing purposes
/clear, nostart
/filnam, myse
resu

/solu
expass, on
seexp, myse, use        ! substructure name and the use pass jobname 
numexp, all,,, yes   ! Expand all modes
solve
fini


!!!!! merge results file
/clear, nostart
/filnam, full
resume
/delete

/post1
nsubsteps = 3         ! **number of harmonic frequencies**
*do,ct, 1, nsubsteps
   file, use
   set, 1, ct
   file, myse
   append, 1, ct
   reswrite, file      ! file name for results file
*enddo

Model Comparison with verification model
 
Fig 2: CMS Model

Fig 3: Verification Model

The results looks pretty similar for the solved frequency.

Archived Model V19+
The archived file can be found here:  Link

All posts on Superelement 
CMS Superelement Harmonic Analysis Link
Reuse CMS Superelement in Ansys Workbench with Expansion Link
Component Mode Synthesis (CMS) with Results Expansion in Ansys Workbench Link
Craig Bampton Method Overview Link
Component Mode Synthesis(CMS) Substructure in ANSYS Workbench Link

Addendum 
In more recent version of Ansys Workbench, distributed file combinations defaults were changed to OFF. This needs to be corrected with appending the following commands to the Analysis A command snippet (Generation Pass).
    dmpopt, esav, yes
    dmpopt, emat, yes
    dmpopt, full, yes

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