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
. G: Z& O! p1 r8 g& G' G% v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：
1 u+ ]& K; q) K1、利用SSUM对ETABLE 动能数据求和获得结构总动能( 1/2m*ω*ω)
2、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。
# h* t' G7 D5 a8 b5 d+ P( V; I2 h下面是《ANSYS Verification Manual》中VM89.DAT稍加修改后提取模态质量的例子：
/PREP7
! ^$ k0 @; O' n1 c# a/TITLE, VM89, NATURAL FREQUENCIES OF A TWO-MASS-SPRING SYSTEM
1 U% C; F' z6 Z" M3 O) pC*** VIBRATION THEORY AND APPLICATIONS, THOMSON, 2ND PRINTING, PAGE 163,EX 6.2-2
ET,1,COMBIN14,,,2
  M) R; |: N& K! Q9 iET,2,MASS21,,,4
R,1,200 ! SPRING CONSTANT = 200
( p6 h5 j5 k8 \- MR,2,800 ! SPRING CONSTANT = 800
R,3,.5 ! MASS = .5
R,4,1 ! MASS = 1
N,1
3 W' x) M  L. \- y6 R! b6 R8 H3 e1 i8 z% I, VN,4,1
4 t1 M' n5 g3 J, b% t: Z& {3 _- @8 t* w+ QFILL
E,1,2 ! SPRING ELEMENT (TYPE,1) AND K = 200 (REAL,1)
) I. c7 D0 n# u, C1 jTYPE,2
: S6 r! S7 Q+ s; yREAL,3
E,2 ! MASS ELEMENT (TYPE,2) AND MASS = .5 (REAL,3)
TYPE,1
REAL,2
/ ^8 E) H0 f5 T4 Z' O' zE,2,3 ! SPRING ELEMENT (TYPE,1) AND K = 800 (REAL,2)
TYPE,2
$ \4 S2 y2 k1 u0 `; x' E) pREAL,4
E,3 ! MASS ELEMENT (TYPE,2) AND MASS = 1 (REAL,4)
0 o4 L0 y' t5 E4 n& GTYPE,1
REAL,1
% t8 |0 Q- G, c* B2 jE,3,4 ! SPRING ELEMENT (TYPE,1) AND K = 200 (REAL,1)
0 O% M( T9 D6 |1 A! q: X# l3 g8 o; hM,2,UX,3
OUTPR,BASIC,1
D,1,UY,,,4
D,1,UX,,,4,3
' h% `9 X& a, |  k" o) S: LFINISH
5 V* N% {: W! Y# h& f) U/SOLU
- I8 P. i  P) ~3 @1 B4 b; F, IANTYPE,MODAL
MODOPT,subspa,2,,,2,ON
MXPAND,2,,,YES
SOLVE
FINISH
/post1
set,1,1
9 x( L/ I' R: w9 r4 a4 E7 Netabl,kene,kene
ssum
*get,keneval1,ssum,,item,kene
  }* w/ J2 L0 M5 K4 D$ p6 J& t*get,freqval1,mode,1,freq
' u1 w1 z: u9 u! Aeigen1=(2*3.14159*freqval1)**2
pmass1=2*keneval1/eigen1
set,1,2
# Y8 ^$ k4 U  E5 x1 b0 betabl,kene,kene
* ~3 S, l% ?2 l3 mssum
1 ]' }  R8 @" p' |/ W$ I; r*get,keneval2,ssum,,item,kene
" e# p$ X: ~0 W. r! C*get,freqval2,mode,2,freq
9 t( `( c# O' O- f2 xeigen2=(2*3.14159*freqval2)**2
pmass2=2*keneval2/eigen2
; l& n+ {# r3 g% E" e: Kfinish