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
. r6 W0 ^& `( H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：
6 _& g1 b- Q6 W1、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。
2 R( ]. b* d3 h2 }0 l下面是《ANSYS Verification Manual》中VM89.DAT稍加修改后提取模态质量的例子：
/PREP7
/TITLE, VM89, NATURAL FREQUENCIES OF A TWO-MASS-SPRING SYSTEM
/ {+ j& M1 L/ I4 g7 rC*** VIBRATION THEORY AND APPLICATIONS, THOMSON, 2ND PRINTING, PAGE 163,EX 6.2-2
ET,1,COMBIN14,,,2
ET,2,MASS21,,,4
R,1,200 ! SPRING CONSTANT = 200
R,2,800 ! SPRING CONSTANT = 800
R,3,.5 ! MASS = .5
R,4,1 ! MASS = 1
N,1
/ V) v% H: O* ]1 H* Z$ j6 j5 B0 [N,4,1
( @  G/ A" A3 G- T0 |6 E# SFILL
E,1,2 ! SPRING ELEMENT (TYPE,1) AND K = 200 (REAL,1)
- Z6 O6 C& P/ H: a* \9 o8 M: {TYPE,2
REAL,3
E,2 ! MASS ELEMENT (TYPE,2) AND MASS = .5 (REAL,3)
+ D8 Q) h& T/ d9 v  [TYPE,1
7 N9 \. u- y: D; \3 Y  HREAL,2
E,2,3 ! SPRING ELEMENT (TYPE,1) AND K = 800 (REAL,2)
7 O, |% F! z$ Q4 q* BTYPE,2
REAL,4
E,3 ! MASS ELEMENT (TYPE,2) AND MASS = 1 (REAL,4)
TYPE,1
5 G' K. ^' n/ X) X5 V9 gREAL,1
E,3,4 ! SPRING ELEMENT (TYPE,1) AND K = 200 (REAL,1)
M,2,UX,3
OUTPR,BASIC,1
D,1,UY,,,4
" r, d8 e  T. `4 oD,1,UX,,,4,3
0 }8 i  P/ i8 R+ o( nFINISH
/SOLU
ANTYPE,MODAL
) e9 Y4 S/ k( aMODOPT,subspa,2,,,2,ON
MXPAND,2,,,YES
SOLVE
, _; B+ x4 f, \9 c/ _FINISH
$ O7 `& t8 p' j, Z) q/post1
set,1,1
etabl,kene,kene
ssum
*get,keneval1,ssum,,item,kene
*get,freqval1,mode,1,freq
eigen1=(2*3.14159*freqval1)**2
& P0 h6 B; o/ tpmass1=2*keneval1/eigen1
* H2 ]4 v3 v3 bset,1,2
etabl,kene,kene
ssum
*get,keneval2,ssum,,item,kene
+ X% y0 a# C- F; H% P*get,freqval2,mode,2,freq
eigen2=(2*3.14159*freqval2)**2
0 s' P7 ?. I" S& S8 W9 |0 B4 n7 \pmass2=2*keneval2/eigen2
finish