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
3 ]7 P' w8 H$ [$ c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)
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。
下面是《ANSYS Verification Manual》中VM89.DAT稍加修改后提取模态质量的例子：
; j+ g  L. P$ V& D3 c+ M& ^/PREP7
: z( {4 e! C- }- Z/TITLE, VM89, NATURAL FREQUENCIES OF A TWO-MASS-SPRING SYSTEM
; {) b# c1 M2 PC*** VIBRATION THEORY AND APPLICATIONS, THOMSON, 2ND PRINTING, PAGE 163,EX 6.2-2
  t4 `+ H& v, aET,1,COMBIN14,,,2
3 S0 V# C$ d- {2 }3 V" uET,2,MASS21,,,4
R,1,200 ! SPRING CONSTANT = 200
6 K9 w* I9 r7 H+ L7 K- uR,2,800 ! SPRING CONSTANT = 800
7 ^4 u2 z5 o" j& U# O# |2 w! ^6 [0 @R,3,.5 ! MASS = .5
R,4,1 ! MASS = 1
* j! a, N  ^; {6 A: F. vN,1
N,4,1
. N+ p' P2 f0 t' t0 ~FILL
E,1,2 ! SPRING ELEMENT (TYPE,1) AND K = 200 (REAL,1)
% T9 o1 w6 w; H1 s, O  f* [TYPE,2
% r: W8 L. p8 W3 p" zREAL,3
E,2 ! MASS ELEMENT (TYPE,2) AND MASS = .5 (REAL,3)
: G% ~( n3 F, p" C& J+ C& G# `TYPE,1
REAL,2
E,2,3 ! SPRING ELEMENT (TYPE,1) AND K = 800 (REAL,2)
TYPE,2
6 x1 u' s5 E5 F  d8 L9 a# f8 g2 XREAL,4
E,3 ! MASS ELEMENT (TYPE,2) AND MASS = 1 (REAL,4)
TYPE,1
REAL,1
E,3,4 ! SPRING ELEMENT (TYPE,1) AND K = 200 (REAL,1)
) I/ g, u% b  q4 dM,2,UX,3
OUTPR,BASIC,1
/ X& l& V* X# M3 }2 ]D,1,UY,,,4
+ T( W7 H# n/ eD,1,UX,,,4,3
: U$ v+ I9 L0 a: E$ ~8 {/ T& nFINISH
5 ]6 e+ v1 D3 g6 K0 O) L/ W/SOLU
& V% u$ U; F2 a' `6 o3 h+ sANTYPE,MODAL
. O4 n& x5 q, C6 {- s  wMODOPT,subspa,2,,,2,ON
MXPAND,2,,,YES
9 @' R6 B& H/ D2 ]# I% s# ], ySOLVE
FINISH
/post1
( B0 v" u! D* x' Z$ @" Qset,1,1
etabl,kene,kene
  v; I) E$ q" c6 c) |ssum
# t4 w! ]+ n1 l( ]1 D6 V9 S2 P$ L2 I*get,keneval1,ssum,,item,kene
7 P: s: `* T5 @- [! s+ F*get,freqval1,mode,1,freq
eigen1=(2*3.14159*freqval1)**2
pmass1=2*keneval1/eigen1
8 {2 q# k+ v. r9 @# o5 ?; \set,1,2
9 S. m) ?& `# `9 N+ ]etabl,kene,kene
ssum
*get,keneval2,ssum,,item,kene
*get,freqval2,mode,2,freq
& r7 ^" ]  E9 weigen2=(2*3.14159*freqval2)**2
0 u( T7 D6 Q5 W0 N4 @7 F+ }pmass2=2*keneval2/eigen2
% L0 p6 n/ S: `5 u3 Wfinish