Question

在Adams里如何建立柔性体，或者Ansys里如果生成中性文件mnf啊

Answer 1

首先，adams2005版本里有autoflex模块，可以由已经建立好的刚体生成柔性体（有限元），但是此模块功能有限，稍微复杂一些的几何体往往生成不了有限元模型，所以之后的版本里就不再有这个模块了。
其次，ansys建立柔性体的大致步骤如下：先建立好有限元模型，然后用mass21单元类型划分外联点单元，建立刚性区域（rigid region），最后把所有单元与刚性区域节点导出。
ansys的help里12.8. Sample Rigid Body Dynamic Analysis里以一个连杆的例子介绍了导出过程，而且有相应命令流，直接在ansys命令窗口复制进去即可运行，输出对应的模态中性文件，命令流如下：
/BATCH,list
/FILNAME,adamsout ! Define jobname
/TITLE,Export flexible component to ADAMS
!
/PREP7 ! Enter preprocessor
!
! Define Parameters of rectangular rod
radh=6 ! Radius of the holes in the rod
thick=10 ! Rod thickness
width=25 ! Rod width
length=300+4*radh ! Rod length
! Build geometry
RECTNG,0,length,0,width
CYL4,2*radh,width/2,radh
CYL4,length-2*radh,width/2,radh
ASBA,1,2
ASBA,4,3
VEXT,1, , ,0,0,thick
!
ET,1,solid45 ! Define SOLID45 as element type 1
ET,2,beam4 ! Define BEAM4 as element type 2
!
MP,EX,1,7.22e4 ! Material of the rectangular rod
MP,PRXY,1,0.34
MP,DENS,1,2.4e-9
!
MP,EX,2,2.1e5 ! Material of the beams used for the spider web
MP,PRXY,2,0.3
MP,DENS,2,0.1e-9
!
R,1,78.528,490.67,490.67,10,10 ! Real constant for BEAM4
RMORE,,,0.85716,0.85716,
!
TYPE,1 ! Set element type attribute pointer to 1
MAT1,1 ! Set material attribute pointer to 1
ESIZE,thick/3,0, ! Define global element size
VSWEEP,1 ! Mesh rod
!
! Define interface points: numbers must be higher than highest
! node number already defined
N,100000,2*radh,width/2,thick/2 ! Define interface point 1
N,100001,length-2*radh,width/2,thick/2 ! Define interface point 2
!
NWPAVE,100000 ! Set working plane to interface point 1
WPSTYL,,,,,,1 ! Set working plane type to cylindrical
CSYS,4 ! Activate working plane
NSEL,S,LOC,X,radh ! Select nodes on cylindrical hole
NSEL,A,,,100000 ! Also select interface node
!
! Generate spider web of beams
*GET,nmin,node,,num,min
*GET,nnum,node,,count
*SET,jj,0
TYPE,2
MAT,2
REAL,1
*DO,jj,1,nnum-2
E,100000,nmin
NSEL,u,,,nmin
*GET,nmin,node,,num,min
*ENDDO
!
ALLS
!
NWPAVE,100001 ! Set working plane to interface point 2
WPSTYL,,,,,,1 ! Set working plane type to cylindrical
CSYS,4 ! Activate working plane
NSEL,S,LOC,X,radh ! Select nodes on cylindrical hole
NSEL,A,,,100001 ! Also select interface node
!
! Generate spider web of beams
*GET,nmin,node,,num,min
*GET,nnum,node,,count
*SET,jj,0
TYPE,2
MAT,2
REAL,1
*DO,jj,1,nnum-2
E,100001,nmin
NSEL,u,,,nmin
*GET,nmin,node,,num,min
*ENDDO
!
ALLS
!
/UNITS,MPA ! Define units used: millimeter
! megagram, second, newton
SAVE ! Save database
NSEL,s,,,100000,100001 ! Select interface points
ADAMS,20,1 ! Start ADAMS macro,
! adamsout.mnf is written
FINISH
/EXIT,nosave

有兴趣可以看看我回答过的相关问题http://zhidao.baidu.com/question/189212331.html与
http://zhidao.baidu.com/question/152781418.html。

我收到了求助，所以在这里进行回答，希望能帮助你~ ，有需要可以给我发信息~

Answer 2

2005版的ADAMS自带AUTOFLEX可做柔性体 再高的版本就不带了 要在ANSYS里生成

追问

那如何在Ansys里生成中性文件mnf，能讲讲具体步骤吗