FEA D3: HARMONIC ANALYSIS OF AN IN-PLANE FRAME

Initial setup

! White canvas
/RGB/RGB, Kywrd, PRED, PGRN, PBLU, N1, N2, NINC, NCNTR Specifies the RGB color values for indices and contours.,INDEX,100,100,100,0
/RGB/RGB, Kywrd, PRED, PGRN, PBLU, N1, N2, NINC, NCNTR Specifies the RGB color values for indices and contours.,INDEX,0,0,0,15
/VIEW/VIEW, WN, XV, YV, ZV Defines the viewing direction for the display.,1,1,2,3
/ANG/ANGLE, WN, THETA, Axis, KINCR Rotates the display about an axis.,1
/ESHAPE/ESHAPE, SCALE, KEY Displays elements with shapes determined from the real constants or section definition.,1.0
! Define constant parameters
! Units: [N],[Nm],[N/m^2=Pa],[N/m]
ELAST=30E9
NU=0.3
RHO=2500E
DAMP=0.02
B1=0.042
H1=0.6
B2=0.6
H2=0.8
F0=8000
FSTART=0
FEND=350
M0=5000
THETAZ0=100

SETUP: element types, real constants, materials, sections

/PREP7/PREP7 Enters the model creation preprocessor.
ETET, ITYPE, Ename, KOP1, KOP2, KOP3, KOP4, KOP5, KOP6, INOPR Defines a local element type from the element library.,1,BEAM188
ETET, ITYPE, Ename, KOP1, KOP2, KOP3, KOP4, KOP5, KOP6, INOPR Defines a local element type from the element library.,2,MASS21
RR, NSET, R1, R2, R3, R4, R5, R6 Defines the element real constants.,1,M0M0 = 5000,M0M0 = 5000,,,,THETAZ0THETAZ0 = 100
MPTEMPMPTEMP, SLOC, T1, T2, T3, T4, T5, T6 Defines a temperature table for material properties.,1,0
MPDATAMPDATA, Lab, MAT, SLOC, C1, C2, C3, C4, C5, C6 Defines property data to be associated with the temperature table.,EX,1,,ELASTELAST = 30E9
MPDATAMPDATA, Lab, MAT, SLOC, C1, C2, C3, C4, C5, C6 Defines property data to be associated with the temperature table.,PRXY,1,,NUNU = 0.3
MPTEMPMPTEMP, SLOC, T1, T2, T3, T4, T5, T6 Defines a temperature table for material properties.,1,0
MPDATAMPDATA, Lab, MAT, SLOC, C1, C2, C3, C4, C5, C6 Defines property data to be associated with the temperature table.,DENS,1,,RHORHO = 2500E
SECTYPESECTYPE, SECID, Type, Subtype, Name, REFINEKEY Associates section type information with a section ID number.,1,BEAM,RECT
SECOFFSETSECOFFSET, Location, OFFSET1, OFFSET2, CG-Y, CG-Z, SH-Y, SH-Z Defines the section offset for cross sections.,CENT
SECDATASECDATA, VAL1, VAL2, VAL3, VAL4, VAL5, VAL6, VAL7, VAL8, VAL9, VAL10, VAL11, VAL12 Describes the geometry of a section.,B1B1 = 0.042,H1H1 = 0.6
SECTYPESECTYPE, SECID, Type, Subtype, Name, REFINEKEY Associates section type information with a section ID number.,2,BEAM,RECT
SECOFFSETSECOFFSET, Location, OFFSET1, OFFSET2, CG-Y, CG-Z, SH-Y, SH-Z Defines the section offset for cross sections.,CENT
SECDATASECDATA, VAL1, VAL2, VAL3, VAL4, VAL5, VAL6, VAL7, VAL8, VAL9, VAL10, VAL11, VAL12 Describes the geometry of a section.,B2B2 = 0.6,H2H2 = 0.8

Modeling

! Keypoints
KK, NPT, X, Y, Z Defines a keypoint.,1,0,0,0
KK, NPT, X, Y, Z Defines a keypoint.,2,0,2,0
KK, NPT, X, Y, Z Defines a keypoint.,3,2,2,0
KK, NPT, X, Y, Z Defines a keypoint.,4,3,2,0
KK, NPT, X, Y, Z Defines a keypoint.,5,3,0,0
! Lines
LL, P1, P2, NDIV, SPACE, XV1, YV1, ZV1, XV2, YV2, ZV2 Defines a line between two keypoints.,1,2
LL, P1, P2, NDIV, SPACE, XV1, YV1, ZV1, XV2, YV2, ZV2 Defines a line between two keypoints.,2,3
LL, P1, P2, NDIV, SPACE, XV1, YV1, ZV1, XV2, YV2, ZV2 Defines a line between two keypoints.,3,4
LL, P1, P2, NDIV, SPACE, XV1, YV1, ZV1, XV2, YV2, ZV2 Defines a line between two keypoints.,4,5
! Meshing
LESIZELESIZE, NL1, SIZE, ANGSIZ, NDIV, SPACE, KFORC, LAYER1, LAYER2, KYNDIV Specifies the divisions and spacing ratio on unmeshed lines.,ALL,0.2
SECNUMSECNUM, SECID Sets the element section attribute pointer.,1
LMESHLMESH, NL1, NL2, NINC Generates nodes and line elements along lines.,1,4,3
SECNUMSECNUM, SECID Sets the element section attribute pointer.,2
LMESHLMESH, NL1, NL2, NINC Generates nodes and line elements along lines.,2,3
TYPETYPE, ITYPE Sets the element type attribute pointer.,2
REALREAL, NSET Sets the element real constant set attribute pointer.,1
EE, I, J, K, L, M, N, O, P Defines an element by node connectivity.,NODE(2,2,0)
! Kinematic constraints
DKDK, KPOI, Lab, VALUE, VALUE2, KEXPND, Lab2, Lab3, Lab4, Lab5, Lab6 Defines DOF constraints at keypoints.,1,ALL,0
DKDK, KPOI, Lab, VALUE, VALUE2, KEXPND, Lab2, Lab3, Lab4, Lab5, Lab6 Defines DOF constraints at keypoints.,5,ALL,0
DD, Node, Lab, VALUE, VALUE2, NEND, NINC, Lab2, Lab3, Lab4, Lab5, Lab6 Defines degree-of-freedom constraints at nodes.,ALL,UZ,0
FINISHFINISH Exits normally from a processor.

Modal analysis

/SOL/SOLU Enters the solution processor.
ANTYPEANTYPE, Antype, Status, LDSTEP, SUBSTEP, Action Specifies the analysis type and restart status.,2

! Analysis setup
MODOPTMODOPT, Method, NMODE, FREQB, FREQE, Cpxmod, Nrmkey, ModType, BlockSize, --, --, Scalekey Specifies modal analysis options.,LANB,10
EQSLVEQSLV, Lab, TOLER, MULT, --, KeepFile Specifies the type of equation solver.,SPAR
MXPANDMXPAND, NMODE, FREQB, FREQE, Elcalc, SIGNIF, MSUPkey, ModeSelMethod Specifies the number of modes to expand and write for a modal or buckling analysis.,10,,,1
MODOPTMODOPT, Method, NMODE, FREQB, FREQE, Cpxmod, Nrmkey, ModType, BlockSize, --, --, Scalekey Specifies modal analysis options.,LANB,10,0,0,,OFF
SOLVESOLVE, Action Starts a solution.
FINISHFINISH Exits normally from a processor.
! Post processing
/POST1/POST1 Enters the database results postprocessor.
SETSET, Lstep, Sbstep, Fact, KIMG, TIME, ANGLE, NSET, ORDER Defines the data set to be read from the results file.,FIRST
*DO*DO, Par, IVAL, FVAL, INC Defines the beginning of a do-loop.,III,1,10
  PLNSOLPLNSOL, Item, Comp, KUND, Fact, FileID Displays results as continuous contours.,U,SUM,2,1.0
  /IMAGE/IMAGE, Label, Fname, Ext, -- Allows graphics data to be captured and saved.,SAVE,strcat(chrval(III),'_eigenshape'),png! Click here to view modeshapes
  SETSET, Lstep, Sbstep, Fact, KIMG, TIME, ANGLE, NSET, ORDER Defines the data set to be read from the results file.,NEXT
*ENDDO*ENDDO Ends a do-loop and starts the looping action.
FINISHFINISH Exits normally from a processor.

Harmonics analyis

/SOL/SOLU Enters the solution processor.
ANTYPEANTYPE, Antype, Status, LDSTEP, SUBSTEP, Action Specifies the analysis type and restart status.,3

! Analysis options
HROPTHROPT, Method, MAXMODE, MINMODE, MCout, Damp Specifies harmonic analysis options.,FULL
HROUTHROUT, Reimky, Clust, Mcont Specifies the harmonic analysis output options.,ON
EQSLVEQSLV, Lab, TOLER, MULT, --, KeepFile Specifies the type of equation solver.,SPAR,0,
! Analysis setup
FKFK, KPOI, Lab, VALUE, VALUE2 Defines force loads at keypoints.,3,FY,F0F0 = 8000,0
! Frequency range and number of steps
HARFRQHARFRQ, FREQB, FREQE, --, LogOpt, FREQARR, Toler Defines the frequency range in a harmonic analysis.,FSTARTFSTART = 0,FENDFEND = 350,
NSUBSTNSUBST, NSBSTP, NSBMX, NSBMN, Carry Specifies the number of substeps to be taken this load step.,(FENDFEND = 350-FSTART)/1,
KBCKBC, KEY Specifies ramped or stepped loading within a load step.,0
! Damping parameters
ALPHADALPHAD, VALUE Defines the mass matrix multiplier for damping.,0
BETADBETAD, VALUE Defines the stiffness matrix multiplier for damping.,0
DMPSTRDMPSTR, COEFF Sets a constant structural damping coefficient.,DAMPDAMP = 0.02
SOLVESOLVE, Action Starts a solution.
FINISHFINISH Exits normally from a processor.

Postprocessing

/POST26/POST26 Enters the time-history results postprocessor.
NSOLNSOL, NVAR, NODE, Item, Comp, Name, SECTOR Specifies nodal data to be stored from the results file.,2,NODE(2,2,0),U,Y,UY_2
/AXLAB/AXLAB, Axis, Lab Labels the X and Y axes on graph displays.,Y,'A [m]'
/AXLAB/AXLAB, Axis, Lab Labels the X and Y axes on graph displays.,X,'f [Hz]'
/XRANGE/XRANGE, XMIN, XMAX Specifies a linear abscissa (X) scale range.,FSTARTFSTART = 0,FENDFEND = 350
/GROPT/GROPT, Lab, KEY Sets various line graph display options.,LOGY,ON
PLCPLXPLCPLX, KEY Specifies the part of a complex variable to display.,0
PRCPLXPRCPLX, KEY Defines the output form for complex variables.,1
PLVARPLVAR, NVAR1, NVAR2, NVAR3, NVAR4, NVAR5, NVAR6, NVAR7, NVAR8, NVAR9, NVAR10 Displays up to ten variables in the form of a graph.,2
/IMAGE/IMAGE, Label, Fname, Ext, -- Allows graphics data to be captured and saved.,SAVE,uy_amplitude,png! Click here to view image
/GROPT/GROPT, Lab, KEY Sets various line graph display options.,LOGY,OFF
/AXLAB/AXLAB, Axis, Lab Labels the X and Y axes on graph displays.,Y,'PHI [DEG]'
PLCPLXPLCPLX, KEY Specifies the part of a complex variable to display.,1
PRCPLXPRCPLX, KEY Defines the output form for complex variables.,1
PLVARPLVAR, NVAR1, NVAR2, NVAR3, NVAR4, NVAR5, NVAR6, NVAR7, NVAR8, NVAR9, NVAR10 Displays up to ten variables in the form of a graph.,2
/IMAGE/IMAGE, Label, Fname, Ext, -- Allows graphics data to be captured and saved.,SAVE,uy_phase_angle,png! Click here to view image