Learning Forum

[Dave Looman]

It's easier to do a hand calculation of mode sup results outside of Workbench. The APDL input file below extracts a real mode and a residual vector and outputs the modal tip displacements.  Multiplying these modal tip displacements by the complex mode coefficients on the MCF file produces the harmonic solution output at the end of the input.

/prep7

et,1,188,,,2

mp,ex,1,3.0e7

mp,nuxy,1,0.3

mp,dens,1,0.000754

sectype,1,beam,rect

secdata,2.0,1.0

n,1

n,2,40

e,1,2

d,1,all

d,2,uz,0

fini

 

/solu

antype,modal

modop,lanb,1

mxpand,1,,,,,yes

resvec,on,

f,2,fy,100

solve

fini

 

/post1

set,1,1

phi_1=uy(2) ! tip displacement for mode 1

set,1,2

phi_2=uy(2)  ! tip displacement for resvec

 

/solu

antype,harmonic

hropt,msup,,,yes

harf,300

nsub,1

dmprat,0.025

resvec,on,

f,2,fy,100

solve

fini

 

/solu

expass,on

expsol,1,1

solve

fini

 

/post26

nsol,2,2,uy

prvar,2             ! harmonic solution

 

MCF File:

Modal Coordinates File - Harmonic Solution
ANSYS 2023 R1          BUILD 23.1        UP20221128    WINDOWS x64 
05/17/2023      13:04:15
Title:                                                                                 
Number of Modes:    2
  Mode:                      1                             2
  Frequency:           0.4129213E+02                 0.3332116E+03
   Frequency          Coordinates...
  0.3000000E+03 -0.2417264E-03 -0.1695691E-05 -0.8894822E-03  0.2114026E-03