Learning Forum

[m.caragiuli]

Hello,

I would like to know if I'm right about the following situation. There is a body to be simulated cut in half in order to apply a symmetry condition (Looking at the picture it is the body at the top side). Actually, I had to cut it furtherly near the symmetry condition due to geometric problems (the body represented at the bottom of the image) thus I would like to know if it is correct to scope the symmetry region to that face while keeping as normal axis the axis that was perpendicular to the original half face. I think it is correct since the symmetry plane is always the same, but the only change is on the scoped face. What do you think?  I just have to constrain the displacement in the direction of the normal axis and the rotations on the symmetry plane.

Following a picture to make it clear.

[peteroznewman]

It's not valid to apply symmetry boundary conditions to nodes off the symmetry plane. Fix the geometry so it can be cut on the proper symmetry plane. I am good at working with geometry if you want to attach a file for me to try to make the cut.

[m.caragiuli]

Many thanks, Peter. I'm thinking of cutting the body by using the symmetry plane shifted a little bit. That case would be valid?

[peteroznewman]

Why can't you cut the symmetric geometry on the symmetry plane?

[m.caragiuli]

I've done it but then there are some problems during meshing and solving due to some bad topologies so since I also have to reduce the faces of the model I prefer to cut by using the symmetry plane but few mm shifted. You have to know that I work only on half of the model and I'm not interested in the symmetry. I just need to constrain it and the symmetry region would be useful, but maybe I could apply a displacement by fixing the normal direction to the symmetry plane and a constrain to fix the two rotations in the plane, what do you think?

[peteroznewman]

If it is it a solid model, there are no rotations to constrain.