Boundary condition to allow nodes to move in parallel?
Boundary condition to allow nodes to move in parallel?
(OP)
Hello everyone,
I have a structure, where I want to constrain the nodes on one surface in X direction such that they are allowed to move, but only in parallel. Or, in other words, all nodes on the surface must move the same distance, if there's movement going on.
There certainly are some workarounds, but is there a simple way to model this? I tried using a (kinematic) coupling-constraint, where I create a reference point on the surface as a reference, but it's slow and has problems to converge. I'm using ABaqus 6.14, static, general.
Thank you very much!

(please note that I'm using a 3D model -- the picture is a 2D representation only)
I have a structure, where I want to constrain the nodes on one surface in X direction such that they are allowed to move, but only in parallel. Or, in other words, all nodes on the surface must move the same distance, if there's movement going on.
There certainly are some workarounds, but is there a simple way to model this? I tried using a (kinematic) coupling-constraint, where I create a reference point on the surface as a reference, but it's slow and has problems to converge. I'm using ABaqus 6.14, static, general.
Thank you very much!

(please note that I'm using a 3D model -- the picture is a 2D representation only)





RE: Boundary condition to allow nodes to move in parallel?
Another option is an Equation. Place one node of that surface in a set. Place the other nodes in a second set. Create the Equation between the sets.
Abaqus Uses Manual 35.2.1 Linear constraint equations
A MPC would be a third option.
RE: Boundary condition to allow nodes to move in parallel?
When I add kinematic coupling, the simulation doesn't converge anymore:
Here's what I do:
1. Create reference point outside the structure
2. Constraints -> Create Constraint -> Coupling
3. Select the Reference Point
4. Choose "Surface" and select the respective surface
5. In the "Edit Constraints" windows that appears, I select "Coupling Type" Kinematic, "Constrained Degrees of Freedom" U1, UR2, UR3, "Influence Radius" To outermost point on the region. All other options are unchecked.
6. I don't have any other constraints on the Reference Point or on the surface used.
Without adding the constraint, everything converges and the simulation finishes successfully.
RE: Boundary condition to allow nodes to move in parallel?
RE: Boundary condition to allow nodes to move in parallel?
It's also good to know about the first solution with the kinematic coupling. Thanks!
RE: Boundary condition to allow nodes to move in parallel?
RE: Boundary condition to allow nodes to move in parallel?