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：
, }( y; n$ w+ g, m) ?- ]1、利用SSUM对ETABLE 动能数据求和获得结构总动能( 1/2m*ω*ω)
% J( @8 N% H+ A2、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! F( K1 b8 h/ o( u6 g' `下面是《ANSYS Verification Manual》中VM89.DAT稍加修改后提取模态质量的例子：
7 ^% b. t0 G& v  F/PREP7
8 P- u. E# T9 s: T- S1 S/TITLE, VM89, NATURAL FREQUENCIES OF A TWO-MASS-SPRING SYSTEM
5 ~5 ?5 p( K% u  m& RC*** VIBRATION THEORY AND APPLICATIONS, THOMSON, 2ND PRINTING, PAGE 163,EX 6.2-2
ET,1,COMBIN14,,,2
: G1 F, T: g2 w/ C. K! dET,2,MASS21,,,4
( e! b& y: t9 n' X6 o8 o/ e  x' YR,1,200 ! SPRING CONSTANT = 200
0 p- f1 V# S* y# e0 kR,2,800 ! SPRING CONSTANT = 800
R,3,.5 ! MASS = .5
R,4,1 ! MASS = 1
6 O' L* {3 j5 y+ f2 @; Q) x1 E, I, MN,1
N,4,1
FILL
E,1,2 ! SPRING ELEMENT (TYPE,1) AND K = 200 (REAL,1)
TYPE,2
5 l+ R) M: {3 VREAL,3
& B; P8 Z# a' FE,2 ! MASS ELEMENT (TYPE,2) AND MASS = .5 (REAL,3)
TYPE,1
) O* l' l& D( Y! UREAL,2
' E" [4 S% l# R" \6 zE,2,3 ! SPRING ELEMENT (TYPE,1) AND K = 800 (REAL,2)
TYPE,2
REAL,4
E,3 ! MASS ELEMENT (TYPE,2) AND MASS = 1 (REAL,4)
TYPE,1
REAL,1
) v! Y* T$ S  d, c& M5 ZE,3,4 ! SPRING ELEMENT (TYPE,1) AND K = 200 (REAL,1)
2 W! n( n! h+ q) b, l4 Z5 WM,2,UX,3
OUTPR,BASIC,1
D,1,UY,,,4
0 f8 T4 S2 y" m2 t8 bD,1,UX,,,4,3
, o. u, y% J4 {- z& G5 N& o4 }; \  A. CFINISH
" e7 i# A( a: ?9 W5 T2 D/ n. [/SOLU
" L. p/ F7 R# L: DANTYPE,MODAL
MODOPT,subspa,2,,,2,ON
+ h+ i4 f- a5 z; W% K3 W' o6 mMXPAND,2,,,YES
; N& Q" R8 N& j5 C  I" WSOLVE
4 l) C' v3 p7 uFINISH
% r# n) Q, T) I9 r' a0 c% g/post1
6 d) G6 _4 ?% ~$ F# E: g) |set,1,1
# \1 d1 s9 k9 ~! f+ betabl,kene,kene
* E1 N( j7 H; rssum
*get,keneval1,ssum,,item,kene
*get,freqval1,mode,1,freq
" R4 ^- }+ `  F" F4 Keigen1=(2*3.14159*freqval1)**2
pmass1=2*keneval1/eigen1
set,1,2
etabl,kene,kene
2 n3 f& \: [; b1 lssum
*get,keneval2,ssum,,item,kene
) n% n5 y* n4 D9 L& d  S*get,freqval2,mode,2,freq
eigen2=(2*3.14159*freqval2)**2
8 Z% f0 \6 N2 ^% d& Dpmass2=2*keneval2/eigen2
3 K( H$ m  M% v6 @: c5 K9 Xfinish