一定需要吗?[em08]
我也见过没有做模态分析的就直接去做谐响应分析的!
这个是ANSYS验证手册中的VM90,就是直接做的谐响应分析!
我认为应该如果想知道谐响应分析中共振频率,需要做模态分析去找到固有频率.
但是只从做谐响应分析的角度来说,模态分析不是做谐响应分析的一个必要的步骤!
/COM,ANSYS MEDIA REL. 9.0 (10/15/2004) REF. VERIF. MANUAL: REL. 9.0
/VERIFY,VM90
/PREP7
JPGPRF,500,100,1 ! MACRO TO SET PREFS FOR JPEG PLOTS
/SHOW,JPEG
/TITLE, VM90, HARMONIC RESPONSE OF A TWO-MASS-SPRING SYSTEM
C*** VIBRATION THEORY AND APPLICATIONS, THOMSON, 2ND PRINTING, PAGE 178,EX 6.6-1
ANTYPE,HARMIC ! HARMONIC RESPONSE ANALYSIS
HROPT,REDUC ! REDUCED HARMONIC RESPONSE
HROUT,OFF ! PRINT RESULTS AS AMPLITUDES AND PHASE ANGLES
ET,1,COMBIN14,,,2
ET,2,MASS21,,,4
R,1,200 ! SPRING CONSTANT = 200
R,2,.5 ! MASS = 0.5
N,1
N,4,1
FILL
E,1,2
TYPE,2
REAL,2
E,2 ! MASS ELEMENT
TYPE,1
REAL,1
E,2,3 ! SPRING ELEMENT
TYPE,2
REAL,2
E,3 ! MASS ELEMENT
TYPE,1
REAL,1
E,3,4 ! SPRING ELEMENT
M,2,UX,3
OUTPR,BASIC,1
NSUBST,30 ! 30 INTERVALS WITHIN FREQ. RANGE
HARFRQ,,7.5 ! FREQUENCY RANGE FROM 0 TO 7.5 HZ
KBC,1 ! STEP BOUNDARY CONDITION
D,1,UY,,,4
D,1,UX,,,4,3
F,2,FX,200
FINISH
/SOLU
SOLVE
FINISH
/POST26
FILE,,rfrq
NSOL,2,2,U,X,2UX ! STORE UX DISPLACEMENTS
NSOL,3,3,U,X,3UX
PRVAR,2,3
*GET,X1,VARI,2,RTIME,1.5
*GET,X2,VARI,3,RTIME,1.5
*GET,X3,VARI,2,RTIME,4
*GET,X4,VARI,3,RTIME,4
*GET,X5,VARI,2,RTIME,6.5
*GET,X6,VARI,3,RTIME,6.5
/GRID,1 ! TURN GRID ON
/AXLAB,Y,DISP ! Y-AXIS LABEL DISP
PLVAR,2,3 ! DISPLAY VARIABLES 2 AND 3
*DIM,LABEL,CHAR,6,2
*DIM,VALUE,,6,3
LABEL(1,1) = 'X1, in ','X2, in ','X1, in ','X2, in ','X1, in ','X2, in '
LABEL(1,2) = 'f=1.5 Hz','f=1.5 Hz','f=4 Hz ','f=4 Hz ','f=6.5 Hz','f=6.5 Hz'
*VFILL,VALUE(1,1),DATA,.82272,.46274,.51145,1.2153,.58513,.26966
*VFILL,VALUE(1,2),DATA,ABS(X1),ABS(X2),ABS(X3),ABS(X4),ABS(X5),ABS(X6)
V1 = ABS(X1/.82272)
V2 = ABS(X2/.46274)
V3 = ABS(X3/.51145)
V4 = ABS(X4/1.2153)
V5 = ABS(X5/.58513)
V6 = ABS(X6/.26965)
*VFILL,VALUE(1,3),DATA,V1,V2,V3,V4,V5,V6
/COM
/OUT,vm90,vrt
/COM,------------------- VM90 RESULTS COMPARISON ---------------
/COM,
/COM, | TARGET | ANSYS | RATIO
/COM,
*VWRITE,LABEL(1,1),LABEL(1,2),VALUE(1,1),VALUE(1,2),VALUE(1,3)
(1X,A8,A8,' ',F10.5,' ',F10.5,' ',1F5.3)
/COM,-----------------------------------------------------------
/COM,
/COM,-----------------------------------------------------------
/COM,NOTE: THERE ARE VERIFIED RESULTS IN VM90 NOT CONTAINED IN
/COM,THIS TABLE
/COM,-----------------------------------------------------------
/OUT
FINISH
*LIST,vm90,vrt
[ 本帖最后由 xuruikl 于 2007-10-22 09:19 编辑 ] |