boundary conditions

[ftiphain]

hello, here I wanted to know if it was possible to define boundary conditions on a surface and not on nodes? it is to model points of electric welding?
thank you

 

[gwolf]

It depends what sort of boundary condition you want to apply and for what purpose. Heat flux, film, pressure for example are all applied to element faces rather than nodes. If you want to model a structural constraint you can either use constraints on nodes, MPC's attached to nodes, or contact from an adjoining structure.

It would help if you described what you are trying to model and why.

 

[ftiphain]

in fact i would like to lock one or more elements, in order to modelize points of electric welding.
I would like to block elements as one can block nodes with the order:
.
.
*BOUNDARY
NODE_SET, ENCASTRE
.
.

 

[gwolf]

Constraining the nodes on the relevant element faces will have the same effect.

In any case you will end up with random numbers for stress. This is usually done by constraining one node, reading off the forces and then using hand calcs to assess the weld.