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：
1、利用SSUM对ETABLE 动能数据求和获得结构总动能( 1/2m*ω*ω)
* ]% `6 d: G4 p$ C- ?! j: [6 k# H2、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。
% f% q& T2 W2 x  _* g# l6 a下面是《ANSYS Verification Manual》中VM89.DAT稍加修改后提取模态质量的例子：
0 W, Z" ]. g0 z; x; c' M/PREP7
/TITLE, VM89, NATURAL FREQUENCIES OF A TWO-MASS-SPRING SYSTEM
7 B3 C1 O* Q8 O2 E* \" z+ ZC*** VIBRATION THEORY AND APPLICATIONS, THOMSON, 2ND PRINTING, PAGE 163,EX 6.2-2
% v' U3 D5 o( Z& w0 F' OET,1,COMBIN14,,,2
8 t( Q# Z$ u8 W, [1 M6 CET,2,MASS21,,,4
  f7 T& z0 F6 Q/ D! b3 c6 ^R,1,200 ! SPRING CONSTANT = 200
R,2,800 ! SPRING CONSTANT = 800
R,3,.5 ! MASS = .5
R,4,1 ! MASS = 1
N,1
N,4,1
FILL
E,1,2 ! SPRING ELEMENT (TYPE,1) AND K = 200 (REAL,1)
TYPE,2
REAL,3
% D# i8 e6 ~; [E,2 ! MASS ELEMENT (TYPE,2) AND MASS = .5 (REAL,3)
2 u5 D) b4 E8 A0 B# m& CTYPE,1
REAL,2
9 a1 i4 N% V* b; KE,2,3 ! SPRING ELEMENT (TYPE,1) AND K = 800 (REAL,2)
* R8 ]$ p- y- [6 uTYPE,2
, b; g8 J3 v0 n. }( i# sREAL,4
E,3 ! MASS ELEMENT (TYPE,2) AND MASS = 1 (REAL,4)
- N2 C1 E- y1 Q9 Z2 gTYPE,1
REAL,1
E,3,4 ! SPRING ELEMENT (TYPE,1) AND K = 200 (REAL,1)
1 G) A, ~+ j6 S: IM,2,UX,3
* o8 C% h: r( o1 lOUTPR,BASIC,1
D,1,UY,,,4
D,1,UX,,,4,3
FINISH
/SOLU
+ O0 _4 w0 f% u1 A, R# }ANTYPE,MODAL
) y7 d; z* Q7 _/ }" ]MODOPT,subspa,2,,,2,ON
MXPAND,2,,,YES
SOLVE
FINISH
- k4 H0 ?" Q5 D% k# n  I) C+ O. z/post1
set,1,1
etabl,kene,kene
. Q6 F% U. ~+ E! J& xssum
) ?" U) p9 q3 v: D3 k/ ?*get,keneval1,ssum,,item,kene
*get,freqval1,mode,1,freq
  O8 f0 p' k4 ]* n2 meigen1=(2*3.14159*freqval1)**2
pmass1=2*keneval1/eigen1
6 K1 c6 O* v- r5 U& H# bset,1,2
etabl,kene,kene
ssum
1 P! [/ w' [+ G3 m& k*get,keneval2,ssum,,item,kene
7 g  W3 ^7 u  s; t*get,freqval2,mode,2,freq
eigen2=(2*3.14159*freqval2)**2
pmass2=2*keneval2/eigen2
finish