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 n# D+ \8 Z7 e: k, E3 i1、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。
" T. O6 T0 _- T$ W' h下面是《ANSYS Verification Manual》中VM89.DAT稍加修改后提取模态质量的例子：
! x0 c/ F! V6 r4 f2 j& Y, N/PREP7
/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
% J  m2 v$ i. w" }, {/ sET,2,MASS21,,,4
R,1,200 ! SPRING CONSTANT = 200
, n2 Z4 [2 Z% Z" v+ iR,2,800 ! SPRING CONSTANT = 800
R,3,.5 ! MASS = .5
R,4,1 ! MASS = 1
2 \" o& B4 u! ^: tN,1
( p5 w% f% R  \; Z4 jN,4,1
FILL
E,1,2 ! SPRING ELEMENT (TYPE,1) AND K = 200 (REAL,1)
TYPE,2
REAL,3
E,2 ! MASS ELEMENT (TYPE,2) AND MASS = .5 (REAL,3)
& i3 w+ x, B) W+ Z  R2 N* `8 u" STYPE,1
0 n0 K/ p/ J! ~6 F2 \REAL,2
) |/ R* l5 j! ^& ~1 rE,2,3 ! SPRING ELEMENT (TYPE,1) AND K = 800 (REAL,2)
0 Q- j& x; s  A$ d: e7 R6 M, ATYPE,2
4 u& N' a9 [3 X8 z: AREAL,4
E,3 ! MASS ELEMENT (TYPE,2) AND MASS = 1 (REAL,4)
TYPE,1
, u3 b5 t6 H" vREAL,1
, Q7 L! L% t/ I! pE,3,4 ! SPRING ELEMENT (TYPE,1) AND K = 200 (REAL,1)
M,2,UX,3
" g5 h/ G  x+ W( s. a) tOUTPR,BASIC,1
0 A0 R$ u8 ~+ ?8 m$ F; S- @2 kD,1,UY,,,4
! \9 r, `" `9 r9 S9 dD,1,UX,,,4,3
+ G% M6 |# M( f" u; t) iFINISH
/SOLU
9 c7 @- U4 m( H. |# C: b& EANTYPE,MODAL
$ v* y, t: }7 w8 q# x! `MODOPT,subspa,2,,,2,ON
MXPAND,2,,,YES
7 t2 u: {5 c* x; \' y* tSOLVE
FINISH
/post1
set,1,1
1 h9 [, x8 n, ^8 n1 Vetabl,kene,kene
, y" e3 e6 |, J, N: @ssum
*get,keneval1,ssum,,item,kene
. ~; _1 h8 z7 |$ G0 g*get,freqval1,mode,1,freq
- a+ D) e+ F& p* A. b: Heigen1=(2*3.14159*freqval1)**2
% B' d4 o! ^0 @3 t9 [9 Zpmass1=2*keneval1/eigen1
- \7 N& @9 P- Xset,1,2
8 b, n1 L( j7 M" {etabl,kene,kene
8 v. ]1 j  O6 W  ossum
7 N8 _2 b6 X# J) g3 l*get,keneval2,ssum,,item,kene
*get,freqval2,mode,2,freq
eigen2=(2*3.14159*freqval2)**2
pmass2=2*keneval2/eigen2
finish