ANSYS Craig Bampton command 生成柔性体文件

yxyuiui

MOTION帮助文件中说ANSYS用Craig Bampton方法生成柔性体文件要加入以下的命令，今天做了一个简单的例子，现贴出完整的命令和模型，和大家分享一下。


FINISH      ! Make sure we are at BEGIN level   
/CLEAR      ! Clear model since no SAVE found
~PARAIN,'AnsysModal','x_t','.\Desktop\',SOLIDS,0,0
导入放在桌面上的模型：


/prep7
et,1,solid45
et,2,mass21
mp,ex,1,2e1
mp,nuxy,1,0.3
mp,dens,1,7.86e3
! create keypoint at center of cylider I/O point
KBETW,2,1,0,RATI,0.5,   
KBETW,3,4,0,RATI,0.5,   
KBETW,21,22,0,RATI,0.5,
KBETW,5,6,0,RATI,0.5,   
KBETW,7,8,0,RATI,0.5,   
KBETW,24,25,0,RATI,0.5,
!create kp,23,26


KDELE,21,22
KDELE,24,25
KPLOT
/REPLOT
vplot
/replot

esize,0.002
mshape,1,3d
mshkey,0
vsel,all
vmesh,all


R,2,1e-5,1e-5,1e-5,1e-5,1e-5,1e-5
ksel,s,,,23,26,3
katt,1,2,2,0  ! Associates attributes with the selected, unmeshed keypoints.
                       !KATT, MAT, REAL, TYPE, ESYS
kmesh,all
allsell
eplot
!!!!!!!!!---create rigid area
nsel,s,,,1619
cm,master1,node
nsel,s,,,1620
cm,master2,node
asel,s,,,1,2
nsla,s,1                   !NSLA, Type, NKEY
cm,slave1,node
asel,s,,,5,6
nsla,s,1
cm,slave2,node
CMGRP,assembly1,MASTER1,SLAVE1   !create assembly 1
cmgrp,assembly2,master2,slave2          !create assembly 2
CMSEL,S,ASSEMBLY1   
NPLOT


/auto,1
/replot,fast   !zoom all
!!!!!!!!!!!!!!!!create rigid area 1
cmsel,s,master1
cmsel,a,slave1
cerig,1619,all,all



!!!!!!!!!!!!!!!!!create rigid area 2
cmsel,s,slave2
cmsel,a,master2
cerig,1620,all,all


allsel,all
/replot



finish
!!!!!!!!!!setp 1. generation pass
allsel
/FILNAME,craig-bampton_solution_1
/solu
antype,substr
cmsopt,fix,30,0,0,,0
seopt,temp_subelem,2,0,0
lumpm,on
m,1619,ux,,,uy,uz,rotx,roty
m,1620,ux,,,uy,uz,rotx,roty
solve
finish
save
!!!!!!setp 2. use pass as help file
/CLEAR,NOSTART                  ! Clears the database.
/FILNAME,TEMP_USECMS
/PREP7
et,1,matrix50
type,1
se,temp_subelem
finish

/solu
antype,modal
modopt,lanb,30,0,1e6
lumpm,yes
mxpand,30
solve
finish
save

!!!!!!!!!!!!!step 3. Expansion pass
/clear,nostart
/FILNAME,craig-bampton_solution_1
resume
/solu
expass,on
SEEXP,TEMP_SUBELEM,TEMP_USECMS
NUMEXP,ALL, , ,YES
ALLSEL,ALL,ALL
OUTRES,ALL,NONE        ! Controls the solution data written to the database.
LUMPM,ON             ! Specifies a lumped mass matrix formulation.
OUTRES,NSOL,ALL
OUTPR,NSOL,ALL            ! Controls the solution printout.
OUTRES,STRS,ALL
/TITLE,Ansys Craig-Bampton Solution.1
solve

finish
save

zheyu19890417

不错！收藏了

lyemechanics

谢谢分享

LJ11

我想问问楼主，他的模态怎么计算，用自由模态还是约束模态啊

yxyuiui

LJ11 发表于 2015-11-17 21:11
我想问问楼主，他的模态怎么计算，用自由模态还是约束模态啊

这个我还不太确定，自由模态前6阶频率基本为0，约束模态前6阶不为0；用LMS motion自动生成的柔性体文件前6阶是不为0的，也就是约束模态，这个能说明要用约束模态吗？

LJ11

yxyuiui 发表于 2015-11-18 13:12
这个我还不太确定，自由模态前6阶频率基本为0，约束模态前6阶不为0；用LMS motion自动生成的柔性体文件前 ...

能，但是我看在它在算模态的时候也没施加约束啊，所以一直质疑lms算的模态