beam structure and rotation constraints

[Stefal639]

after so long I rewrite you because I have a problem.
We are planning with an arm of a 32-metre truck pump and we are now having to do the static and modal analysis of the structure.
we recreated in ansys classic, with a model of rods, all arms and cinematisms, imposed with the beam model all sections of interest.
Here comes the dilemma: default ansys requires that each beam is framed to the next, i.e. that all the auctions that generate a certain keypoint are framed in that node.
I would like that in this node there is a rotation bond, but not for all the auctions that generate such a keypoint (I would use the endrelease command), but, for example, in a kp from where 3 rods are generated, that a rod considers that kp as a rotation bond, while the other 2 consider it as an ink.
I have searched for various commands, but sincerely we have not understood anything... or little.

Can you help me?
Thank you very much

 

[Vmax]

I haven't used the classic (10 years?), but it seems a bit complex.
it could be better from the point of view of modeling, to double the bond locally in two constraints, neighboring but not coincident, reached by a rigid element, they could thus frame two beams and to hinge the third on different constraints.

 

[eih64]

help ansys is your reference.
easy reading of the help ....

end of release
endrelease, --, tolerance, dof1, dof2, dof3, dof4 specifies degrees of freedom to be decoupled for end release. (values to be inserted (rotz for long rotation axis z)
set tolerance to -1 to indicated all selected elements. (if I put -1 works on selected items)
this command specifies end releases for the beam188, beam189, pipe288, and pipe289 elements (specific control for these elements)
the command works on currently selected nodes and elements. (work command on selected nodes and elements)
use the cplist command to list the coupled sets generated by the endrelease command. (with this command I see in cp inserted it is clear that if I want to free the rotation along z the cp will not be present)

Clearly not?
the solution is in you, read the help ansys as + times said and the game is made
- - - updated - - - -help ansys is your reference.
easy reading of the help ....

end of release
endrelease, --, tolerance, dof1, dof2, dof3, dof4 specifies degrees of freedom to be decoupled for end release. (values to be inserted (rotz for long axis z rotation)
set tolerance to -1 to indicated all selected elements. (if I put -1 works on selected items)
this command specifies end releases for the beam188, beam189, pipe288, and pipe289 elements (specific control for these elements)
the command works on currently selected nodes and elements. (work command on selected nodes and elements)
use the cplist command to list the coupled sets generated by the endrelease command. (with this command I see in cp inserted it is clear that if I want to free the rotation along z the cp will not be present)

Clearly not?
the solution is in you, read the help ansys as + times said and the game is made

 

[Stefal639]

the endrelease is not good because it changes the internal constraints also between the knots of the individual beams.
at the end I solved in the following way:
double all kp.
the bodies that in a knot are continuous, so where there is a bond of continuity in the real object, build them by making them coincide the lines that compose it with the same kp (then a nice piece of paper will help you to score all the kp)...if you have to make a rod that has a hinge on another rod you will build by doing so that the zipper (for example, you can choose that constraint you) to understand the rigid bodies in contact with each other with a type of bond, the kp that contact the 2 bodies must be distinguished.
you mesha everything
you go to "constraint coupling equation" and go to "coincident nodes",
defines the constraints that one wants to attribute to the "coincident" nodes (therefore leaves the degrees of freedom that one wants to give to the bond).
finished :

in this way (I took a week to invent myself is cagata di method)