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
) ]$ i/ A  N1 [+ W& K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：
" s+ X  `- l, G# m4 K0 e+ d& ]. P# `1、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。
/ k4 J2 Z' m: z" P2 Z3 m+ ^下面是《ANSYS Verification Manual》中VM89.DAT稍加修改后提取模态质量的例子：
$ B6 V) m4 `- |4 ]/PREP7
) N! D4 I+ E9 B; E2 J/TITLE, VM89, NATURAL FREQUENCIES OF A TWO-MASS-SPRING SYSTEM
C*** VIBRATION THEORY AND APPLICATIONS, THOMSON, 2ND PRINTING, PAGE 163,EX 6.2-2
ET,1,COMBIN14,,,2
5 g# u; A& Q/ j  V' ~9 ?) FET,2,MASS21,,,4
. Q' x" s; T8 ZR,1,200 ! SPRING CONSTANT = 200
R,2,800 ! SPRING CONSTANT = 800
8 Z4 L0 e4 [' n& OR,3,.5 ! MASS = .5
- t. E- T! T  b- Y! Q- ?; N9 nR,4,1 ! MASS = 1
1 r7 J0 M) |$ w7 n6 V7 u: g( z3 ]N,1
N,4,1
3 d3 G  U; C: Y: a' q# z' @7 R# QFILL
7 h  `- i: y, X' @0 ~4 i  B2 WE,1,2 ! SPRING ELEMENT (TYPE,1) AND K = 200 (REAL,1)
TYPE,2
  }+ v5 ~& v# ?8 Z% iREAL,3
E,2 ! MASS ELEMENT (TYPE,2) AND MASS = .5 (REAL,3)
TYPE,1
REAL,2
0 r  l* {9 @& m$ `+ ~E,2,3 ! SPRING ELEMENT (TYPE,1) AND K = 800 (REAL,2)
TYPE,2
, h, h6 P8 R0 W4 a# R8 M9 EREAL,4
3 |7 Q, v0 \# [$ Q9 h. JE,3 ! MASS ELEMENT (TYPE,2) AND MASS = 1 (REAL,4)
% Z, m; c$ b& x) Y" Z, ~4 F8 PTYPE,1
  Z0 B' G6 g( W! t; u% lREAL,1
E,3,4 ! SPRING ELEMENT (TYPE,1) AND K = 200 (REAL,1)
M,2,UX,3
OUTPR,BASIC,1
D,1,UY,,,4
; v$ G& i$ W2 u2 S$ v; ]& h4 BD,1,UX,,,4,3
" N# n! X) W2 ]. e; n! KFINISH
- W6 A5 m- W1 k! k/ h/SOLU
3 m9 B! \' u! H2 aANTYPE,MODAL
MODOPT,subspa,2,,,2,ON
MXPAND,2,,,YES
1 h. Q2 K. Q7 vSOLVE
1 \4 D& J5 L0 l& |# Z8 PFINISH
/post1
+ i% Y- q6 K7 O4 xset,1,1
etabl,kene,kene
2 H- [1 N; z+ X" lssum
*get,keneval1,ssum,,item,kene
*get,freqval1,mode,1,freq
  e+ ~8 L8 W" e& U5 neigen1=(2*3.14159*freqval1)**2
) q+ [6 b, g( J' S9 X( b8 |pmass1=2*keneval1/eigen1
set,1,2
/ P9 z: R* a" p: C2 \etabl,kene,kene
ssum
*get,keneval2,ssum,,item,kene
1 `  `+ u( ?& v0 z% L% H*get,freqval2,mode,2,freq
eigen2=(2*3.14159*freqval2)**2
4 Y  d! A& D0 E- Ppmass2=2*keneval2/eigen2
finish