/COM,ANSYS MEDIA REL. 2024R2 (05/10/2024) REF. VERIF. MANUAL: REL. 2024R2
/verify,vm149
/title,vm149,Residual Vector in Mode Superposition Harmonic Analysis
/com,
/com, Verification manual to verify the effect of residual
/com, vector to improve the solution accuracy in modal
/com, response analysis
/com,
/com, Reference: J.M.Dickens,J.M.Nakagawa,M.J.Wittbrodt
/com, "A critique of mode acceleration and modal truncation
/com, augmentation methods for modal response analysis"
/com, computers & structures,Vol.62,No.6,pp 985-998,1997
/com,
/com, ********************************
/com, CASE1: EXTRACTING ALL THE MODES
/com, ********************************
/out,vm149_scratch
/filename,case1
/prep7
et,1,combin14,,,2 ! 2D Spring-damper element
et,2,mass21,,,4 ! 2D Mass without rotary inertia
et,3,mass21,,,4 ! 2D Mass without rotary inertia
r,1,10000 ! Stiffness for spring element
r,2,1 ! Mass
r,3,0.5 ! Mass
n,1
n,2,1
n,3,2
n,4,3
n,5,4
n,6,5
e,1,2 ! Spring 1
e,2,3 ! Spring 2
e,3,4 ! Spring 3
e,4,5 ! Spring 4
e,5,6 ! Spring 5
type,2
real,2
e,2 ! Mass 1
e,3 ! Mass 2
e,4 ! Mass 3
type,3
real,3
e,5 ! Mass 4
d,1,all
d,6,all
nsel,s,,,2,5
d,all,uy
nsel,all
finish
/solution
antype,modal
modopt,lanb,4 ! Extracting all modes
mxpand,all,,,yes
f,4,fx,1 ! Generate load vector for harmonic analysis
solve
fini
/solution
antype,harmic,new
hropt,msup,4,, ! Mode superposition harmonic analysis
outres,all,all
fdele,all
lvscale,1 ! Scaling the load vector
harfrq,3,70 ! Frequency range
dmprat,0.02 ! Damping
nsubst,500
kbc,1
save
solve
fini
/solution
expass,on
outres,all,all
numexp,all,,,yes
solve
finish
/post26
file,case1,rst
numvar,20
/com, *******************************************************
/com, Computing the 1st peak displacement and spring force
/com, *********************************************************
nsol,2,4,u,x,4ux
realvar,4,2,,,UXR ! Real value of UX
imagin,5,2,,,UXI ! Imaginary value of UX
prod,6,4,4,,UXR_2
prod,7,5,5,,UXI_2
add,8,6,7,,UXR_2+UXI_2
sqrt,9,8,,,ampl_disp,,,1 ! Amplitude
esol,10,4,4,smisc,1
realvar,11,10,,,ForceR ! Real value of Spring force
imagin,12,10,,,ForceI ! Imaginary value of Spring force
prod,13,11,11,,ForceR_2
prod,14,12,12,,ForceI_2
add,15,13,14,,ForceR_2+ForceI_2
sqrt,16,15,,,ampl_force,,,1 ! Amplitude
/grid,1
/gropt,logy,1
/xrange,3,70
/axlab,y,amplitude_disp_force
plvar,9,16
prvar,9,16
*get,ux_max_all,vari,9,extrem,vmax
*get,force_max_all,vari,16,extrem,vmax
*get,freq_ux_all,vari,9,extrem,tmax
*get,freq_force_all,vari,16,extrem,tmax
/com, *******************************************************
/com, Computing the 2nd peak spring force
/com, *******************************************************
timerange,11,70 ! Listing values between 11hz to 70Hz
store,new ! Store new set of data
esol,10,4,4,smisc,1
realvar,11,10,,,ForceR ! Real value of Spring force
imagin,12,10,,,ForceI ! Imaginary value of Spring force
prod,13,11,11,,ForceR_2
prod,14,12,12,,ForceI_2
add,15,13,14,,ForceR_2+ForceI_2
sqrt,16,15,,,ampl_force,,,1 ! Amplitude
/grid,1
/gropt,logy,1
/xrange,3,70
/axlab,y,amplitude_disp_force
plvar,16
prvar,16
*get,force_max_all2,vari,16,extrem,vmax
*dim,label,char,5,1
*dim,value,,5,3
label(1,1)='UX_MAX'
label(2,1)='F_MAX'
label(3,1)='FREQ_UX'
label(4,1)='FREQ_F'
label(5,1)='F_MAX2'
*vfill,value(1,1),data,2.500e-03
*vfill,value(1,2),data,ux_max_all
*vfill,value(1,3),data,abs(2.500e-03/ux_max_all)
*vfill,value(2,1),data,10.000
*vfill,value(2,2),data,force_max_all
*vfill,value(2,3),data,abs(10.000/force_max_all)
*vfill,value(3,1),data,10.100
*vfill,value(3,2),data,freq_ux_all
*vfill,value(3,3),data,abs(10.100/freq_ux_all)
*vfill,value(4,1),data,10.100
*vfill,value(4,2),data,freq_force_all
*vfill,value(4,3),data,abs(10.100/freq_force_all)
*vfill,value(5,1),data,4.5
*vfill,value(5,2),data,force_max_all2
*vfill,value(5,3),data,abs(4.5/force_max_all2)
save,table_1
fini
/clear,nostart
/out,
/com, *******************************************
/com, CASE2: EXTRACTING 1 MODE + RESIDUAL VECTOR
/com, ********************************************
/out,vm149_scratch,,,append
/title,vm149,Residual Vector in Mode Superposition Harmonic Analysis
/filename,case2
/prep7
et,1,combin14,,,2 ! 2D Spring-damper element
et,2,mass21,,,4 ! 2D Mass without rotary inertia
et,3,mass21,,,4 ! 2D Mass without rotary inertia
r,1,10000 ! Stiffness for spring element
r,2,1 ! Mass
r,3,0.5 ! Mass
n,1
n,2,1
n,3,2
n,4,3
n,5,4
n,6,5
e,1,2 ! Spring 1
e,2,3 ! Spring 2
e,3,4 ! Spring 3
e,4,5 ! Spring 4
e,5,6 ! Spring 5
type,2
real,2
e,2 ! Mass 1
e,3 ! Mass 2
e,4 ! Mass 3
type,3
real,3
e,5 ! Mass 4
d,1,all
d,6,all
nsel,s,,,2,5
d,all,uy
nsel,all
finish
/solution
antype,modal
modopt,lanb,1 ! Extract 1 mode
mxpand,1,,,yes
resvec,on ! Compute residual vector
f,4,fx,1 ! Generate load vector
solve
fini
/post1
set,1,2
*get,residual_vector,active,0,set,freq
finish
/solution
antype,harmic,
resvec,on ! Include residual vector
hropt,msup,1,,
fdele,all
lvscale,1 ! Scale load vector
harfrq,3,70 ! Excitation frequency range
dmprat,0.02 ! Damping
nsubst,500
kbc,1
save
solve
fini
/solution
expass,on
outres,all,all
numexp,all,,,yes
solve
finish
/post26
file,case2,rst
numvar,20
/com, *******************************************************
/com, Computing the 1st peak displacement and spring force
/com, *********************************************************
nsol,2,4,u,x,4ux
realvar,4,2,,,UXR ! Real value of UX
imagin,5,2,,,UXI ! Imaginary value of UX
prod,6,4,4,,UXR_2
prod,7,5,5,,UXI_2
add,8,6,7,,UXR_2+UXI_2
sqrt,9,8,,,ampl_disp,,,1
esol,10,4,4,smisc,1
realvar,11,10,,,ForceR ! Real value of Spring force
imagin,12,10,,,ForceI ! Imaginary value of Spring force
prod,13,11,11,,ForceR_2
prod,14,12,12,,ForceI_2
add,15,13,14,,ForceR_2+ForceI_2
sqrt,16,15,,,ampl_force,,,1
/grid,1
/gropt,logy,1
/xrange,3,70
/axlab,y,amplitude_disp_force
plvar,9,16
prvar,9,16
*get,ux_max_residual,vari,9,extrem,vmax
*get,force_max_residual,vari,16,extrem,vmax
*get,freq_ux_residual,vari,9,extrem,tmax
*get,freq_force_residual,vari,16,extrem,tmax
/com, *********************************************************
/com, Computing the 2nd peak spring force
/com, *********************************************************
timerange,11,70
store,new
esol,10,4,4,smisc,1
realvar,11,10,,,ForceR ! Real value of Spring force
imagin,12,10,,,ForceI ! Imaginary value of Spring force
prod,13,11,11,,ForceR_2
prod,14,12,12,,ForceI_2
add,15,13,14,,ForceR_2+ForceI_2
sqrt,16,15,,,ampl_force,,,1 ! Amplitude
/grid,1
/gropt,logy,1
/xrange,3,70
/axlab,y,amplitude_disp_force
plvar,16
prvar,16
*get,force_max_resvec2,vari,16,extrem,vmax
*dim,label,char,6,1
*dim,value,,6,3
label(1,1)='RES_MODE'
label(2,1)='UX_MAX'
label(3,1)='F_MAX'
label(4,1)='FREQ_UX'
label(5,1)='FREQ_F'
label(6,1)='F_MAX2'
*vfill,value(1,1),data,21.865
*vfill,value(1,2),data,residual_vector
*vfill,value(1,3),data,abs(21.865/residual_vector)
*vfill,value(2,1),data,2.500e-03
*vfill,value(2,2),data,ux_max_residual
*vfill,value(2,3),data,abs(2.500e-03/ux_max_residual)
*vfill,value(3,1),data,10.000
*vfill,value(3,2),data,force_max_residual
*vfill,value(3,3),data,abs(10.000/force_max_residual)
*vfill,value(4,1),data,10.100
*vfill,value(4,2),data,freq_ux_residual
*vfill,value(4,3),data,abs(10.100/freq_ux_residual)
*vfill,value(5,1),data,10.100
*vfill,value(5,2),data,freq_force_residual
*vfill,value(5,3),data,abs(10.100/freq_force_residual)
*vfill,value(6,1),data,4.5
*vfill,value(6,2),data,force_max_resvec2
*vfill,value(6,3),data,abs(4.5/force_max_resvec2)
save,table_2
finish
resume,table_1
/com,
/out,vm149,vrt
/com,
/com, ------------------------------VM149 RESULTS COMPARISON----------------------
/com,
/com, | TARGET | Mechanical APDL | RATIO
/com,
/com,
/com, Extracting all modes
/com, --------------------
/com,
/com,
*VWRITE,LABEL(1,1),VALUE(1,1),VALUE(1,2),VALUE(1,3)
(1X,A14,' ',F12.5,' ',F12.5,' ',F12.3)
/com,
/com,
/NOPR,
resume,table_2
/GOPR
/com,
/com, Extracting 1 mode + residual vector
/com, -----------------------------------
/com,
/com,
/com,
*VWRITE,LABEL(1,1),VALUE(1,1),VALUE(1,2),VALUE(1,3)
(1X,A14,' ',F12.5,' ',F12.5,' ',F12.3)
/com,
/com,
/NOPR,
/com,
/com,
/com, --------------------------------------------------------------------------------
/out,
*list,vm149,vrt
finish
