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：
1、利用SSUM对ETABLE 动能数据求和获得结构总动能( 1/2m*ω*ω)
! x' f; r. `+ A* _% N! Z$ l2、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。
" E7 |( n4 k  w/ x+ b下面是《ANSYS Verification Manual》中VM89.DAT稍加修改后提取模态质量的例子：
/PREP7
' D4 L! \5 W4 f# ^4 R- P/TITLE, VM89, NATURAL FREQUENCIES OF A TWO-MASS-SPRING SYSTEM
C*** VIBRATION THEORY AND APPLICATIONS, THOMSON, 2ND PRINTING, PAGE 163,EX 6.2-2
4 t, w7 @+ y, KET,1,COMBIN14,,,2
( [& W- {( F, o. A1 L5 yET,2,MASS21,,,4
R,1,200 ! SPRING CONSTANT = 200
& Q3 O- M0 e$ \& HR,2,800 ! SPRING CONSTANT = 800
& _5 ?9 \, [, ]R,3,.5 ! MASS = .5
3 R) f6 K2 e  z; RR,4,1 ! MASS = 1
( t$ J' ^2 p0 s( [: [9 P: G  V4 s/ E) x( bN,1
N,4,1
: f8 D0 s4 T  i  {  GFILL
6 c9 x+ B, \! X2 A) F1 mE,1,2 ! SPRING ELEMENT (TYPE,1) AND K = 200 (REAL,1)
# |: }! y2 U: a" k2 t- JTYPE,2
REAL,3
$ X( ]4 W$ k) u# R" `* U0 M5 \E,2 ! MASS ELEMENT (TYPE,2) AND MASS = .5 (REAL,3)
6 k7 V$ N$ N4 d9 c' P1 uTYPE,1
6 w3 w; Z! Y. x% uREAL,2
* q; t0 G3 a) J+ f+ A9 X6 sE,2,3 ! SPRING ELEMENT (TYPE,1) AND K = 800 (REAL,2)
TYPE,2
REAL,4
) @* z; j( U$ M% W$ }$ p" [E,3 ! MASS ELEMENT (TYPE,2) AND MASS = 1 (REAL,4)
TYPE,1
$ [; B; ?8 ?3 W& ]; ?- |+ IREAL,1
+ s) t" A  ?4 V( g. H* [( `; JE,3,4 ! SPRING ELEMENT (TYPE,1) AND K = 200 (REAL,1)
M,2,UX,3
' w8 Q. f( s9 g5 UOUTPR,BASIC,1
  }3 Z, i( i; n* Z* x% Z6 k3 c9 ?1 XD,1,UY,,,4
% N3 v; ?- e" X0 B' i$ @D,1,UX,,,4,3
; S. F7 O& q0 _1 y& I6 l8 CFINISH
. `# o* R+ Q7 P8 \1 \7 o/SOLU
ANTYPE,MODAL
MODOPT,subspa,2,,,2,ON
- S2 x& Z* G$ I; `( cMXPAND,2,,,YES
2 b. P' Z' L4 ?, A5 v' u. NSOLVE
FINISH
: P+ \; @! h0 S0 O1 F0 U! h/post1
set,1,1
  K% l  j# M  `% Z/ _  `: V6 K" Petabl,kene,kene
ssum
*get,keneval1,ssum,,item,kene
2 X; M" Y; \0 U& J$ H  i*get,freqval1,mode,1,freq
& H  b7 `3 N4 e' K+ p8 e0 deigen1=(2*3.14159*freqval1)**2
: D- \0 G8 B  ^1 v( F! kpmass1=2*keneval1/eigen1
% e7 a& l# P* A3 F& fset,1,2
etabl,kene,kene
ssum
*get,keneval2,ssum,,item,kene
*get,freqval2,mode,2,freq
eigen2=(2*3.14159*freqval2)**2
pmass2=2*keneval2/eigen2
/ H' a9 }, d* ]' y% e3 |, xfinish