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
+ c8 @* J* S3 O* _4 Q; b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：
! [! i" E2 |# i( F  o3 y1、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。
1 A; A. T9 j6 _! C& g$ G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" ?: C4 _/PREP7
/TITLE, VM89, NATURAL FREQUENCIES OF A TWO-MASS-SPRING SYSTEM
5 p, ~, P" F. o6 b! V% vC*** VIBRATION THEORY AND APPLICATIONS, THOMSON, 2ND PRINTING, PAGE 163,EX 6.2-2
; D& K( g# G4 m6 GET,1,COMBIN14,,,2
4 G* S9 ^! O/ D' F, O( IET,2,MASS21,,,4
0 ?& J& N, S1 P- NR,1,200 ! SPRING CONSTANT = 200
: F& g4 j9 k# ^0 X: m, ~! q6 Q. |R,2,800 ! SPRING CONSTANT = 800
R,3,.5 ! MASS = .5
  ]' P  d1 A0 g9 k  f1 eR,4,1 ! MASS = 1
# c- n+ g# u! u4 S* ?  n, N( g* WN,1
N,4,1
- C. |! P4 k: u+ M" jFILL
E,1,2 ! SPRING ELEMENT (TYPE,1) AND K = 200 (REAL,1)
; ]3 Z1 M$ U4 n- a1 g. Q9 Z& ^TYPE,2
REAL,3
& _1 K& Y" k' yE,2 ! MASS ELEMENT (TYPE,2) AND MASS = .5 (REAL,3)
TYPE,1
REAL,2
E,2,3 ! SPRING ELEMENT (TYPE,1) AND K = 800 (REAL,2)
! W& ?9 N0 R' X/ u0 B2 g$ vTYPE,2
REAL,4
5 A0 @% _! L# wE,3 ! MASS ELEMENT (TYPE,2) AND MASS = 1 (REAL,4)
TYPE,1
REAL,1
8 n* z5 U3 }) ]0 Q3 b. R$ lE,3,4 ! SPRING ELEMENT (TYPE,1) AND K = 200 (REAL,1)
5 ?7 ^; b8 C9 j9 L$ wM,2,UX,3
OUTPR,BASIC,1
D,1,UY,,,4
D,1,UX,,,4,3
FINISH
/SOLU
ANTYPE,MODAL
MODOPT,subspa,2,,,2,ON
7 J  X- h& O1 n- n. `+ WMXPAND,2,,,YES
0 d/ q0 s4 V: H) _5 l( S4 I" CSOLVE
9 B8 d% D) q8 e% pFINISH
/post1
set,1,1
etabl,kene,kene
5 u4 V8 o8 Z* U1 L' h1 v9 ~) b8 }ssum
*get,keneval1,ssum,,item,kene
: }/ f% v" m% A5 p$ H0 ^*get,freqval1,mode,1,freq
" _* K6 D8 a+ y. k; weigen1=(2*3.14159*freqval1)**2
pmass1=2*keneval1/eigen1
set,1,2
9 |5 E- b9 W7 d* eetabl,kene,kene
ssum
*get,keneval2,ssum,,item,kene
*get,freqval2,mode,2,freq
4 u" s- X! c3 Y0 G( Z( h+ V7 V- feigen2=(2*3.14159*freqval2)**2
) ?8 t4 K0 c' [: H; {9 J$ lpmass2=2*keneval2/eigen2
6 S7 }1 P0 B+ r4 ?# _( _finish