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
6 A; E& u& |/ ~  z% Y; q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)
% i! @% n# [* }2 n3 b( I' M" c2、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。
# O1 }3 O% N. h: G' l- e下面是《ANSYS Verification Manual》中VM89.DAT稍加修改后提取模态质量的例子：
" S4 N+ C0 ?# b: A5 A/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
: R  [5 L1 G+ ]* i1 h) zET,1,COMBIN14,,,2
* c. l- O# o- b. s6 e. k& ~ET,2,MASS21,,,4
' I$ [" N9 t& G2 n8 I' `/ ^- D7 A; ?R,1,200 ! SPRING CONSTANT = 200
* h( i$ N, Y4 H  z0 o! jR,2,800 ! SPRING CONSTANT = 800
( q4 o1 w( z8 l5 Q6 I: t. y' `R,3,.5 ! MASS = .5
7 ^( }+ g! L' U  ~: JR,4,1 ! MASS = 1
; I) C6 i4 ?9 ], [N,1
1 t, ^4 o9 W6 ]0 b  d, A" gN,4,1
FILL
E,1,2 ! SPRING ELEMENT (TYPE,1) AND K = 200 (REAL,1)
TYPE,2
6 z: B" E: h/ G  d" N* @REAL,3
E,2 ! MASS ELEMENT (TYPE,2) AND MASS = .5 (REAL,3)
TYPE,1
) ~  x8 b; p1 MREAL,2
E,2,3 ! SPRING ELEMENT (TYPE,1) AND K = 800 (REAL,2)
3 Z  y* v! P! w! {TYPE,2
REAL,4
E,3 ! MASS ELEMENT (TYPE,2) AND MASS = 1 (REAL,4)
% l0 U/ L4 Z3 M. Y) FTYPE,1
; j8 `* q$ ^  k# C" k0 wREAL,1
E,3,4 ! SPRING ELEMENT (TYPE,1) AND K = 200 (REAL,1)
* m  t+ }7 U$ ^M,2,UX,3
% @+ }- h/ z6 g- H* F5 zOUTPR,BASIC,1
D,1,UY,,,4
& O' C4 a. z0 x! M+ ID,1,UX,,,4,3
FINISH
/SOLU
ANTYPE,MODAL
4 w  L* L& L1 N9 _MODOPT,subspa,2,,,2,ON
4 [) ]4 c! c1 W% NMXPAND,2,,,YES
: T" z" n7 c7 Z9 Q, u% u4 M2 hSOLVE
FINISH
2 V2 D$ ~" R* I9 j; Y+ `/post1
set,1,1
etabl,kene,kene
ssum
) X& I6 c+ r% T# k6 d  _; D7 V*get,keneval1,ssum,,item,kene
' [! [0 F% B9 @. h8 k/ I' f& R# ]*get,freqval1,mode,1,freq
eigen1=(2*3.14159*freqval1)**2
) }# ^- ]# D6 G/ ^3 a! t& ?pmass1=2*keneval1/eigen1
set,1,2
' R2 w. P" _' L4 D5 ietabl,kene,kene
! o1 v7 @% m. d( U! e6 I1 sssum
*get,keneval2,ssum,,item,kene
* \: t- U  X6 i4 \5 O*get,freqval2,mode,2,freq
# E4 r2 \/ m) ueigen2=(2*3.14159*freqval2)**2
pmass2=2*keneval2/eigen2
finish