Newbie: how to make a radial restraint

[Jolilechat]

Hello!

I am starting to learn ANSYS and I'd like to ask for some help. Consider a plate with a hole (see code below).

Please, can you explain me how to create a radial restraint for the hole (that is, the plate can only rotate about the axis of the hole)?

Thank you very much!


/prep7
/title,Plate

l1 = 80.0E-3
l2 = 250.0E-3
l3 = 50.0E-3
a = 20.0E-3
b = 15.0E-3
th = 20.0E-3

ET,1,SHELL63
R,1,th,th,th,th
MP,EX,1,2.0E11
MP,PRXY,1,0.3

TYPE,1
REAL,1
MAT,1

BLC4,0,0,l1,l2

CYL4,l1/2,l3/2,5.0E-3
ASBA,1,2

FINISH

 

[ansysfreak]

Hi

You can determine your boundary conditions by applying your displacements on the lines of the hole.

Grtz Garry

 

[Jolilechat]

You say zero to displacements at all nodes of the boundary of the hole?
If I do it, the plate won't be able to rotate.

 

[EricZhao]

set up a locale cylindarical coordinate at the hole senter. Then applied constraint along the radial direction.

 

[meshparts]

EricZhao,

what you said is not complete. Independent of the active coordinate system, the nodal displacements are in the nodal coordinate system. So:

1) set up a locale cylindarical coordinate at the hole center:

local,1000,1,xcenter,ycenter,zcenter

2) select nodes on the circle:

nsel,s,loc,x,rad

3) Rotate nodal coordinate sistems in the cylindrical coordinate system:

nrotat,all

4) constrain nodes along the radial direction:

d,all,ux,0

 

[meshparts]

Jolilechat,


in your concrete case:

smrtsize,4
amesh,all
local,1000,1,l1/2,l3/2
nsel,s,loc,x,5e-3
nrotat,all
d,all,ux,0
/PBC,U,,1
nplot