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
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：
" @3 V! U: T2 T& K1 m) ]1、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。
* {" n; m" C6 r6 g: F下面是《ANSYS Verification Manual》中VM89.DAT稍加修改后提取模态质量的例子：
  S/ k1 @4 w3 g8 |/PREP7
5 g1 j) x8 G5 K0 l/ }6 @( k) j3 B$ u; ?/TITLE, VM89, NATURAL FREQUENCIES OF A TWO-MASS-SPRING SYSTEM
C*** VIBRATION THEORY AND APPLICATIONS, THOMSON, 2ND PRINTING, PAGE 163,EX 6.2-2
" j% m( c0 _- HET,1,COMBIN14,,,2
9 |3 p6 {0 E' ~% j6 C2 y2 t3 F) XET,2,MASS21,,,4
$ A, w3 x" R3 z* K7 k3 e" P  ?R,1,200 ! SPRING CONSTANT = 200
R,2,800 ! SPRING CONSTANT = 800
' N8 {) h# \3 y+ ZR,3,.5 ! MASS = .5
R,4,1 ! MASS = 1
0 r1 E8 \* T7 C: P. i4 _N,1
N,4,1
FILL
- P& ?: {, e4 SE,1,2 ! SPRING ELEMENT (TYPE,1) AND K = 200 (REAL,1)
8 X4 Z. A. i8 f! z: eTYPE,2
. [! `& t  L% f: |# vREAL,3
7 K+ |/ [; y+ o- RE,2 ! MASS ELEMENT (TYPE,2) AND MASS = .5 (REAL,3)
+ t+ e& s% T7 v( o2 N( c/ d" n( uTYPE,1
REAL,2
E,2,3 ! SPRING ELEMENT (TYPE,1) AND K = 800 (REAL,2)
1 p3 P( O+ w$ fTYPE,2
2 |2 U% X- w) B9 ?REAL,4
# I) \0 @( V; l4 x8 }" D- J8 ?E,3 ! MASS ELEMENT (TYPE,2) AND MASS = 1 (REAL,4)
( S* |) {) o8 A4 Y# Q$ M5 w7 LTYPE,1
- {+ C3 t" c2 p: JREAL,1
E,3,4 ! SPRING ELEMENT (TYPE,1) AND K = 200 (REAL,1)
M,2,UX,3
6 n; I& |% k& S' l8 K. E6 AOUTPR,BASIC,1
D,1,UY,,,4
D,1,UX,,,4,3
% t. ]% ?: G! U: n( s+ d: AFINISH
/SOLU
ANTYPE,MODAL
. |0 j3 j9 z$ B* KMODOPT,subspa,2,,,2,ON
, S6 T. t% k0 a( U. _( lMXPAND,2,,,YES
) O! g1 m  P" V1 ~% |/ f, d  J/ dSOLVE
% K8 r+ R- f$ R( zFINISH
$ y: Q6 W5 G$ p/ s, b/post1
" |2 t. j' y% U* R' W, b/ _set,1,1
4 \& \! ?  L% Q- K' Y- G& Ietabl,kene,kene
2 S1 B6 l5 l  W- ~+ ?ssum
9 X  N$ u1 E4 b/ q*get,keneval1,ssum,,item,kene
1 _6 V' h1 K3 l5 {* \+ w( P*get,freqval1,mode,1,freq
" i2 k. T6 `4 h+ Qeigen1=(2*3.14159*freqval1)**2
  R! ]2 Z! g; c! ?3 |+ k7 Ypmass1=2*keneval1/eigen1
5 F1 @9 h$ |$ \, t& @set,1,2
etabl,kene,kene
ssum
*get,keneval2,ssum,,item,kene
*get,freqval2,mode,2,freq
7 d/ _2 ^5 P+ u! meigen2=(2*3.14159*freqval2)**2
2 [- x( p% E1 x7 L  j) `- x+ ~pmass2=2*keneval2/eigen2
, i, H0 S+ P; G3 M. O8 Gfinish