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)
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。
5 V. y0 y' I9 K+ W  M下面是《ANSYS Verification Manual》中VM89.DAT稍加修改后提取模态质量的例子：
9 Q' s: U' l$ b! I* X3 d/PREP7
* Z0 L2 Q3 v0 P$ }) @/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
ET,2,MASS21,,,4
R,1,200 ! SPRING CONSTANT = 200
R,2,800 ! SPRING CONSTANT = 800
+ F( U3 h. {) y. c' Y( w; X  HR,3,.5 ! MASS = .5
R,4,1 ! MASS = 1
N,1
N,4,1
FILL
4 N) q( g/ [$ q  C* w( EE,1,2 ! SPRING ELEMENT (TYPE,1) AND K = 200 (REAL,1)
1 a2 E0 ^: \& h% m: ?* l# D* M* JTYPE,2
REAL,3
! a; I7 E3 h0 }1 _) X! j$ QE,2 ! MASS ELEMENT (TYPE,2) AND MASS = .5 (REAL,3)
; j% I- K. a' x4 [) T3 f8 I3 B! JTYPE,1
8 W! ^& r, n* Y0 I. t& f+ C# RREAL,2
E,2,3 ! SPRING ELEMENT (TYPE,1) AND K = 800 (REAL,2)
TYPE,2
8 S+ j. _1 o# v- u/ Y( \REAL,4
" x! t- H7 j, ME,3 ! MASS ELEMENT (TYPE,2) AND MASS = 1 (REAL,4)
TYPE,1
REAL,1
8 M2 \1 W. w; O7 WE,3,4 ! SPRING ELEMENT (TYPE,1) AND K = 200 (REAL,1)
M,2,UX,3
0 {. B# v% `6 ^" DOUTPR,BASIC,1
D,1,UY,,,4
D,1,UX,,,4,3
( `1 Z, a* x9 W& l8 jFINISH
/SOLU
/ F6 c4 ?% x% C) N5 z& Q% YANTYPE,MODAL
4 N% _/ T/ J; Y6 ?4 IMODOPT,subspa,2,,,2,ON
+ g# o: J% I2 s" E/ d8 LMXPAND,2,,,YES
SOLVE
3 ?2 D' [! O3 R; KFINISH
/post1
) v  i% a1 [9 {5 h- Nset,1,1
8 |! m4 I% @8 ]% _, G+ Metabl,kene,kene
ssum
: ?- n6 `+ f+ I$ @0 q*get,keneval1,ssum,,item,kene
4 ~0 C" K4 j* z8 K2 I8 L/ D4 v*get,freqval1,mode,1,freq
eigen1=(2*3.14159*freqval1)**2
pmass1=2*keneval1/eigen1
set,1,2
7 _6 n+ I5 h% ]( j/ hetabl,kene,kene
0 U, o* K8 v+ Issum
$ _; r6 m% E# R$ O  `/ f. N1 G2 A*get,keneval2,ssum,,item,kene
; r8 U6 N# D) a" j7 k% k( p5 N*get,freqval2,mode,2,freq
4 s" u1 W( x9 peigen2=(2*3.14159*freqval2)**2
pmass2=2*keneval2/eigen2
( Q: I2 [9 z' s, N6 x# R3 n* ofinish