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：
4 o- `; E+ h' a1、利用SSUM对ETABLE 动能数据求和获得结构总动能( 1/2m*ω*ω)
, i. ~7 }$ N$ y0 `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。
: [6 T" R7 U3 K' s9 r' A- D( \* `' [下面是《ANSYS Verification Manual》中VM89.DAT稍加修改后提取模态质量的例子：
/PREP7
" R( P5 i6 P: [( K/TITLE, VM89, NATURAL FREQUENCIES OF A TWO-MASS-SPRING SYSTEM
C*** VIBRATION THEORY AND APPLICATIONS, THOMSON, 2ND PRINTING, PAGE 163,EX 6.2-2
- S) N4 K$ k7 ?; M8 RET,1,COMBIN14,,,2
ET,2,MASS21,,,4
& M) _5 y8 R/ v6 x* L, aR,1,200 ! SPRING CONSTANT = 200
R,2,800 ! SPRING CONSTANT = 800
5 e# S- Z& ^+ n! |5 t/ b6 |R,3,.5 ! MASS = .5
; F5 d1 p# ?- j4 P7 Y5 a$ i/ H6 FR,4,1 ! MASS = 1
5 s% F/ o+ _. y( gN,1
1 ^1 l# Y( F  y% Z& T" L) P1 x$ \, qN,4,1
$ I5 W3 @" Z$ ]5 D$ oFILL
E,1,2 ! SPRING ELEMENT (TYPE,1) AND K = 200 (REAL,1)
# E1 c% v, l+ Q3 s, P* C  r2 ~TYPE,2
REAL,3
E,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)
TYPE,2
REAL,4
" B2 W7 Y7 J/ E5 P4 iE,3 ! MASS ELEMENT (TYPE,2) AND MASS = 1 (REAL,4)
TYPE,1
$ _; U' ?% Q9 S5 e$ jREAL,1
, _7 l. f$ K0 XE,3,4 ! SPRING ELEMENT (TYPE,1) AND K = 200 (REAL,1)
  ~5 }- K# n/ `' OM,2,UX,3
1 A% P4 H% ]0 r5 K" a, [OUTPR,BASIC,1
D,1,UY,,,4
/ D- v: h$ v" C4 o5 A3 XD,1,UX,,,4,3
FINISH
5 _% `( {- M$ T- E1 ^/ E/SOLU
ANTYPE,MODAL
MODOPT,subspa,2,,,2,ON
* C1 j0 K/ \) A- s- Q* UMXPAND,2,,,YES
' F8 x, S6 Z* o7 p/ A# U5 W* LSOLVE
% k6 i+ ~  m8 ]: P6 ?+ q" ?FINISH
+ @4 m7 N: c; l$ B+ `/ `/post1
+ {# x4 c: I2 Y- E+ w1 Zset,1,1
etabl,kene,kene
ssum
*get,keneval1,ssum,,item,kene
*get,freqval1,mode,1,freq
eigen1=(2*3.14159*freqval1)**2
pmass1=2*keneval1/eigen1
set,1,2
etabl,kene,kene
ssum
: S' u6 D* h6 q*get,keneval2,ssum,,item,kene
*get,freqval2,mode,2,freq
eigen2=(2*3.14159*freqval2)**2
pmass2=2*keneval2/eigen2
finish