Mechanical APDL Structural Analysis Guide

k,1,0,0,0! Create model and mesh it

k,2,4,0,0

l,1,2

lesize,1,,,4

lmesh,all

allsel,all

nsel,s,loc,x,0

d,all,all,0! Fix end of beam

nsel,all

finish

/solu

antype,static

nsubs,10,10,10

time,1.0

nlgeom,on

nsel,s,loc,x,4

f,all,fx,1e5

f,all,fy,-1e6

nsel,all

rescontrol,define,all,1! Needed to generate restart file

cnvtol,f,,1e-3! Tighter tolerance than default for better accuracy

cnvtol,m,,1e-4

solve

finish! Completion of nonlinear base analysis

!! CASE 1

!! Linear perturbation modal analysis starts here

/solu! First phase of linear perturbation

antype,static,restart,1,5,perturb! Restart in the middle

perturb,modal,,,allkeep

solve,elform

nsel,s,loc,x,4! Second phase of linear perturbation

ddele,all,ux

nsel,all

modopt,lanb,24! Compute all the modes possible

mxpand,24,,,yes

solve

finish

!! Linear perturbation ends here

!! MSUP harmonic analysis starts here, uses modes from linear perturbation

!! MSUP is a downstream analysis

/solu

antype,harmonic

hropt,msup,24

outres,all,all

harfrq,23.5,24.5

nsubs,10,10,10

kbc,1

nsel,s,loc,x,4

f,all,fy,-1e7,2000

nsel,all

solve

finish

!! Expansion pass

/solu

expass,on

outres,all,all

numexp,all,,,yes

solve

finish

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Linear Perturbation Analysis