Ansys里模态质量矩阵的提取方法

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Ansys里模态质量矩阵的提取方法
' K, J9 d; ?% `" }) t模态质量矩阵的提取方法，请大家分享：模态分析过程中打开振型型则化开关(MODOPT命令的Nrmkey设置为ON)，ANSYS程序将自动将每阶模态的最大位移单位化，就可以提取模态质量。计算方法如下：
# Z1 j9 h  ]+ ]" q- \& D1、利用SSUM对ETABLE 动能数据求和获得结构总动能( 1/2m*ω*ω)
! X4 U; i3 K3 D2、将结构总动能除以1/2m*ω*ω得到m ，其中ω 是系统的角频率。
下面是《ANSYS Verification Manual》中VM89.DAT稍加修改后提取模态质量的例子：
. O2 X  }) ]. Y- k. M& Y9 L9 E8 v/PREP7
/TITLE, VM89, NATURAL FREQUENCIES OF A TWO-MASS-SPRING SYSTEM
! C8 ]6 a* Q1 V9 ?7 wC*** VIBRATION THEORY AND APPLICATIONS, THOMSON, 2ND PRINTING, PAGE 163,EX 6.2-2
# F% N/ A; _4 H+ K. O3 e: EET,1,COMBIN14,,,2
0 n: L2 p6 [' _* I! _0 pET,2,MASS21,,,4
R,1,200 ! SPRING CONSTANT = 200
R,2,800 ! SPRING CONSTANT = 800
& e4 j& h' `- K4 B% rR,3,.5 ! MASS = .5
R,4,1 ! MASS = 1
5 U7 d+ U8 y8 K7 {0 e- j# i1 zN,1
N,4,1
FILL
8 |+ o8 C. w. `E,1,2 ! SPRING ELEMENT (TYPE,1) AND K = 200 (REAL,1)
TYPE,2
3 g# F8 b) h' `4 WREAL,3
% z, ?% D8 _8 c# n6 e. JE,2 ! MASS ELEMENT (TYPE,2) AND MASS = .5 (REAL,3)
TYPE,1
REAL,2
E,2,3 ! SPRING ELEMENT (TYPE,1) AND K = 800 (REAL,2)
2 M/ B% R, w6 O: QTYPE,2
7 K' K. R, N# R9 @REAL,4
+ w. I* G: F1 p* hE,3 ! MASS ELEMENT (TYPE,2) AND MASS = 1 (REAL,4)
5 h$ @" j0 o8 [2 K7 w7 B% R0 LTYPE,1
REAL,1
E,3,4 ! SPRING ELEMENT (TYPE,1) AND K = 200 (REAL,1)
( T* e1 L% w% R* R/ _7 H, OM,2,UX,3
/ m1 v1 z% f+ ]OUTPR,BASIC,1
" w8 U3 i4 K  E) Q/ o5 yD,1,UY,,,4
; U4 n* R! i- a( J! S3 Y. C$ Z% m$ yD,1,UX,,,4,3
, q' R9 A4 Y) H2 {/ I  S  kFINISH
/SOLU
ANTYPE,MODAL
' e1 |4 h3 w! HMODOPT,subspa,2,,,2,ON
MXPAND,2,,,YES
SOLVE
/ ~; H% f( [4 EFINISH
8 a# c: i) X" v5 ?# e! E% C/post1
- U! a" p/ T! I7 oset,1,1
( W# y* v* w& e% N" Xetabl,kene,kene
ssum
*get,keneval1,ssum,,item,kene
7 D4 w1 g$ G' w& n  K*get,freqval1,mode,1,freq
# Z  [" J5 M0 E; b0 Seigen1=(2*3.14159*freqval1)**2
pmass1=2*keneval1/eigen1
  B; y' k6 D- f- l4 eset,1,2
  I/ U5 P1 o8 _4 Q7 w( F. m  uetabl,kene,kene
ssum
( A! X% n0 _2 B; I' W*get,keneval2,ssum,,item,kene
. h/ u  ?9 m3 B6 M$ g; A*get,freqval2,mode,2,freq
eigen2=(2*3.14159*freqval2)**2
pmass2=2*keneval2/eigen2
finish