Ansys里模态质量矩阵的提取方法

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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：
+ [7 r" L1 {8 u4 ^# n  Q( C1、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。
4 y9 P: ^% c6 P4 L1 `下面是《ANSYS Verification Manual》中VM89.DAT稍加修改后提取模态质量的例子：
2 J0 v# c' q% q5 J! d2 L/PREP7
/TITLE, VM89, NATURAL FREQUENCIES OF A TWO-MASS-SPRING SYSTEM
C*** VIBRATION THEORY AND APPLICATIONS, THOMSON, 2ND PRINTING, PAGE 163,EX 6.2-2
ET,1,COMBIN14,,,2
ET,2,MASS21,,,4
R,1,200 ! SPRING CONSTANT = 200
R,2,800 ! SPRING CONSTANT = 800
7 D/ X8 P- |% O) Z& A: CR,3,.5 ! MASS = .5
R,4,1 ! MASS = 1
- \4 X* M# }% jN,1
: B" l+ ?3 k! P9 A" C, ~N,4,1
* m6 T7 ~/ v4 e. u2 cFILL
0 T$ w+ P+ T# ^3 N9 m! DE,1,2 ! SPRING ELEMENT (TYPE,1) AND K = 200 (REAL,1)
% p- ^! n: v  d! T. U# jTYPE,2
6 g) z1 c0 I# L- T( F5 iREAL,3
5 r% q# k6 k% s4 l6 TE,2 ! MASS ELEMENT (TYPE,2) AND MASS = .5 (REAL,3)
TYPE,1
4 A2 o& Y: [; V$ xREAL,2
E,2,3 ! SPRING ELEMENT (TYPE,1) AND K = 800 (REAL,2)
9 V9 n0 O2 g+ ?. c( @% r/ JTYPE,2
REAL,4
' p4 ^) O+ R  JE,3 ! MASS ELEMENT (TYPE,2) AND MASS = 1 (REAL,4)
, G, p5 d' w/ e4 ~# l! gTYPE,1
REAL,1
E,3,4 ! SPRING ELEMENT (TYPE,1) AND K = 200 (REAL,1)
8 r; G/ l) Y. ]- O; U# dM,2,UX,3
OUTPR,BASIC,1
% p1 ?/ h4 k7 C' A4 }7 M  E( |D,1,UY,,,4
D,1,UX,,,4,3
FINISH
6 l( S' p; P  W$ G; a- c/SOLU
$ A' z2 F; i) `# O& L& ^: Q/ S* ?ANTYPE,MODAL
# C5 f% v) [: M7 l9 s. j) KMODOPT,subspa,2,,,2,ON
MXPAND,2,,,YES
: T1 m5 d$ d; d& N  E/ JSOLVE
3 f/ m3 i' f0 M( i. qFINISH
/post1
set,1,1
etabl,kene,kene
. n3 y! i2 m- ^$ Y6 s  L  c8 wssum
& o, ~9 K( k, @& ?*get,keneval1,ssum,,item,kene
  l$ W+ D/ N% t8 ?' E2 e; t2 o*get,freqval1,mode,1,freq
eigen1=(2*3.14159*freqval1)**2
pmass1=2*keneval1/eigen1
set,1,2
2 y! W: i  A( v) W" S) j9 P" getabl,kene,kene
  R9 F/ Z4 U/ M1 d; F) o2 Pssum
*get,keneval2,ssum,,item,kene
*get,freqval2,mode,2,freq
7 H3 a, s. v" T" p% n/ v, f$ peigen2=(2*3.14159*freqval2)**2
pmass2=2*keneval2/eigen2
; A# e# e/ j: j/ P& R% V0 Bfinish