Do you have an example that shows exactly how NFORCE calculates
its values in a full harmonic response analysis?


Yes, please see the ANSYS 9.0 input below (which is also attached to
this solution record as "nforce.inp"). This input consists of two blocks
that are connected together by CP (coupled DOF) commands. One
end is fixed and the other end of the cantilever has a tip load applied
to it with both real and imaginary components. The element data is
squared, then summed, then the square root is taken, and then the
data from each each element is summed at a given node. The details
are highlighted in the output results ...


fini
/clear

/title, SRSS Test in Full Harmonic Response Analysis

/plopts,info,1
/view,,1,2,3
/pnum,type,1
/num,1

/prep7
et,1,SOLID45
et,2,SOLID45
r,1
mp,ex,1,30.0e6
mp,nuxy,1,0.30
mp,dens,1,0.0007
block,0,5,0,1,0,1
block,5,10,0,1,0,1
esize,0.50
type,1
vmesh,1
n11=node(5.0,0.0,0.0)
n12=node(5.0,0.0,0.5)
n13=node(5.0,0.0,1.0)
n14=node(5.0,0.5,0.0)
n15=node(5.0,0.5,0.5)
n16=node(5.0,0.5,1.0)
n17=node(5.0,1.0,0.0)
n18=node(5.0,1.0,0.5)
n19=node(5.0,1.0,1.0)
nsel,none
type,2
vmesh,2
n21=node(5.0,0.0,0.0)
n22=node(5.0,0.0,0.5)
n23=node(5.0,0.0,1.0)
n24=node(5.0,0.5,0.0)
n25=node(5.0,0.5,0.5)
n26=node(5.0,0.5,1.0)
n27=node(5.0,1.0,0.0)
n28=node(5.0,1.0,0.5)
n29=node(5.0,1.0,1.0)
nsel,all
cp,,all,n11,n21
cp,,all,n12,n22
cp,,all,n13,n23
cp,,all,n14,n24
cp,,all,n15,n25
cp,,all,n16,n26
cp,,all,n17,n27
cp,,all,n18,n28
cp,,all,n19,n29
eplot
fini

/solu
antype,modal
modopt,lanb,10 ! block Lanczos modal analysis
mxpand,10,,,yes
nsel,s,loc,x,0.0
d,all,all,0.0
nsel,all
solve
save
*get,freq1,mode,1,freq ! 1st frequency
*get,freq2,mode,2,freq ! 2nd frequency
*get,freq3,mode,3,freq ! 3rd frequency
*get,freq4,mode,4,freq ! 4th frequency
*get,freq5,mode,5,freq ! 5th frequency
*get,freq6,mode,6,freq ! 6th frequency
fini

! MODE FREQUENCY(HERTZ)
!
! 1 334.7519161629
! 2 334.7519161638
! 3 2027.060147620
! 4 2027.060147620
! 5 3210.528718405
! 6 5201.027253448
! 7 5417.594104150
! 8 5417.594104150
! 9 9651.400218760
! 10 10029.39527864

/prep7
mp,dmpr,1,0.10 ! constant material damping coefficient
fini

/solu
antype,harmic ! harmonic response analysis
hropt,full ! full harmonic response
hrout,off ! print results asamplitudes and phase angles
outpr,basic,1
harfrq,0.99*freq4 ! close to 4th natural frequency
kbc,1 ! step applied boundary conditions
nsel,s,loc,x,10.0
nsel,r,loc,y,1.0
f,all,fy,1.0,0.5 ! real and imaginary tip load ...
nsel,all
solve
save
fini

/post1
/graph,full
force,total ! NFORC uses FORCE,TOTAL by default

*status,n16
*status,n26
nsel,s,node,,n16 ! block 1 node with two elements summed
nsel,a,node,,n26 ! corresponding block 2 node ...
esln

set,,, ,,, ,1 ! real data
presol,f

set,,, ,,, ,2 ! imaginary data
presol,f

hrcplx,,,360 ! amplitude values for omegat=360
presol,f
nforce

/eof

= = = = = = = = = = = = = = = = = = = = = = = = = = = = = = = = = = = = = = = = =
= = = = = = = = = = = = = = = = = = = = = = = = = = = = = = = = = = = = = = = =
= = = = = = = = = = = = = = = = = = = = = = = = = = = = = = = = = = = = = = = = =

***** ANSYS RESULTS INTERPRETATION (POST1) *****

Use Full element graphics for all elements

USE TOTAL FORCES FOR SOLUTION RESULTS

NAME VALUE TYPE DIMENSIONS
N16 46.0000000 SCALAR.
NAME VALUE TYPE DIMENSIONS
N26 156.000000 SCALAR

= = = = = = = = = = = = = = = = = = = = = = = = = = = = = = = = = = = = = = = = =
= = = = = = = = = = = = = = = = = = = = = = = = = = = = = = = = = = = = = = = =
= == = = = = = = = = = = = = = = = = = = = = = = = = = = = = = = = = = = = = = =

USE DATA SET 1 ON RESULT FILE FOR LOAD CASE 0

TIME/FREQUENCY= 2006.8

PRINT F ELEMENT SOLUTION PER ELEMENT

***** POST1 ELEMENT NODE TOTAL FORCE LISTING *****

LOAD STEP= 1 SUBSTEP= 1
FREQ= 2006.8 LOAD CASE= 0

THE FOLLOWING X,Y,Z FORCES ARE IN GLOBAL COORDINATES

ELEM= 30 FX FY FZ
77 2.3575 -0.15698 0.24832E-01
68 -2.6409 0.80705E-01-0.72433E-02
90 -1.1190 0.10444 -0.13653E-02
99 1.3801 -0.19393 0.74470E-02
44 2.3530 -0.17279 -0.35565E-01
35 -2.6361 0.90853E-01 0.22767E-01
46-1.0987 0.11456 0.49823E-02 => (FX_R1)**2= 1.2071417
66 1.3988 -0.20969 -0.16887E-01

ELEM= 40 FX FY FZ
99 -1.3801 -0.19393 -0.74470E-02
90 1.1190 0.10444 0.13653E-02
78 2.6409 0.80705E-01 0.72433E-02
88 -2.3576 -0.15698 -0.24832E-01
66 -1.3988 -0.20969 0.16887E-01
46 1.0987 0.11456 -0.49822E-02 => (FX_R2)**2 = 1.2071417
45 2.6361 0.90853E-01-0.22767E-01
48 -2.3530 -0.17279 0.35565E-01

ELEM= 61 FX FY FZ
166 2.6416 -0.10545 0.18075E-01
168 -2.7989 0.28410E-01 0.85658E-04
190 -1.2864 0.38538E-01 0.67368E-03
188 1.4337 -0.12925 0.56061E-02
133 2.6368 -0.11566 -0.22945E-01
135 -2.7941 0.32767E-01 0179 -4.5650 0.47156E-01 0.17930E-01
178 4.5789 0.42510E-01 0.16974E-01
156 2.2815 0.59681E-01-0.11343E-01 => (FX_I4)**2 = 5.2052423
157 -2.2870 0.67503E-01-0.12237E-01
155 -4.5561 0.53074E-01-0.13897E-01
146 4.5693 0.47764E-01-0.11440E-01

= = = = = == = = = = = = = = = = = = = = = = = = = = = = = = = = = = = = = = = =
= = = = = = = = = = = = = = = = = = = = = = = = = = = = = = = = = = = = = = = =
= = = = = = = = = = = = = = = = = = = = = = = = = = = = = = = = = = = = = = = = =

HRCPLX MACRO FREQUENCY= NEAR 0.00 ANGLE= 360.000

PRINT F ELEMENT SOLUTION PER ELEMENT

SRSS Test in Full Harmonic Response Ana FREQ=2006.789 AMPLITUDE

***** POST1 ELEMENT NODE TOTAL FORCE LISTING *****

CALCULATED LOAD CASE= 0

THE FOLLOWING X,Y,Z FORCES ARE IN GLOBAL COORDINATES

ELEM= 30 FX FY FZ
77 4.9402 0.21806 0.40886E-01
68 5.2877 0.23761 0.88031E-02
90 2.3958 0.26368 0.31141E-02.
.99 2.7189 0.271710.12753E-01
44 4.9295 0.24102 0.51969E-01
35 5.2770 0.24905 0.26377E-01
46 2.3701 0.27521 0.60630E-02 => FX_A1 = (1.2071417 + 4.4053812)**0.5
66 2.7413 0.29471 0.27381E-01 = (5.6125229)**0.5 = 2.3690764

ELEM= 40 FX FY FZ
99 2.7189 0.27171 0.12753E-01
90 2.3958 0.26368 0.31141E-02
78 5.2877 0.23761 0.88032E-02
88 4.9402 0.21806 0.40886E-01
66 2.7413 0.29471 0.27381E-01
46 2.3701 0.27521 0.60629E-02 => FX_A2 = (1.2071417 + 4.4053812)**0.5
45 5.2770 0.24905 0.26377E-01 = (5.6125229)**0.5 = 2.3690764
48 4.9295 0.24102 0.51969E-01

ELEM= 61 FX FY FZ
166 5.2865 0.13316 0.25274E-01
168 5.3611 0.14057 0.18385E-01
190 2.6280 0.15113 0.65027E-02
188 2.6967 0.15585 0.83738E-02
133 5.2758 0.14262 0.25719E-01
135 5.3509 0.14494 0.17240E-01
157 2.6214 0.15646 0.12272E-01
156 2.7001 0.16624 0.16725E-01=> FX_A3 = (2.0845584 + 5.2052423)**0.5.= (7.2898007)**0.5 = 2.6999631
ELEM= 71 FXFYFZ
188 2.6967 0.15585 0.83737E-02
190 2.6280 0.15113 0.65028E-02
179 5.3612 0.14058 0.18386E-01
178 5.2865 0.13316 0.25273E-01
156 2.7002 0.16624 0.16725E-01 => FX_A3 = (2.0848472 + 5.2052423)**0.5
157 2.6214 0.15645 0.12272E-01 = (7.2900895)**0.5 = 2.7000166
155 5.3510 0.14494 0.17240E-01
146 5.2758 0.14262 0.25719E-01

= = = = = = = = = = = = = = = = = = = = = = = = = = = = = = = = = = = = = = = = =
= = = = = = = = = = = = = = = = = = = = = = = = = = = = = = = = = = = = = = = =
= = = = = = = = = = = = = = = = = = = = = = = = = = = = = = = = = = = = = = = = =

***** POST1 NODAL TOTAL FORCE SUMMATION *****

LOAD STEP= 9999 SUBSTEP= 0

THE FOLLOWING X,Y,Z FORCES ARE IN GLOBAL COORDINATES

NODE FX FY FZ
46 4.740 0.5504 0.1213E-01 => FX_ASUM = 2.3690764 + 2.3690764 = 4.7381528
156 5.400 0.3325 0.3345E-01 => FX_ASUM = 2.6999631 + 2.7000166 = 5.3999797

***** SUMMATION OF TOTALFORCES AND MOMENTS IN GLOBAL COORDINATES *****
FX = 10.14055
FY = 0.8828991
FZ = 0.4557521E-01MX = -0.8601115
MY = 9.912676
MZ = -0.6557808

SUMMATION POINT= 0.0000 0.0000 0.0000

= = = = = = = = = = = = = = = = = = = = = = = = = = = =





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