Simulating composite square tubing with foam core

Chris84

Hey all,

 

I need some help with a composite simulation. I want to model a foam core, that's surrounded entirely by a composite laminate. I can think of multiple ways to model that, but I'm not shure, which is the right one.

This is what my sorta test geometry looks like.

 

The section view for that looks like this:

That is with the core being part of the laminate and it obviously overlaps itself, which doesn't seem like the right way of modeling the part.

 

The other way would be with the laminate and the core being part of separate components.

This is with the laminate extended inward:

And this is with the laminate extended outward from the core geometry:

 

Apart from wanting to know, what's the right way to do it and why, there're a few other questions I have:

Hyperworks takes the offset of the layers, which aren't lying directly on the shell geometry into account for its calculations, right?

Is a freeze contact actually the right way to model a contact between a composite and a foam or honeycomb core?

Would rounds be favorable for the laminate geometry (sort of like in the first picture)?

 

That's a rather long question, but I'd really apprectiate some help with this.

Adriano_Koga

is your core completely filled?

If yes, you could just create a solid mesh in the middle, with your core property. 

An if you create an hexa mesh, you could just extract 'faces' to create your shell mesh, and assing your laminate to it. As the mesh will be tied by the nodes, no contact will be necessary.

It's just an idea.

 

Chris84

Yeah, my core is completely filled. I already tried that before (successfully). That should give me the same result as a freeze contact, right?
And thanks for the hint with the faces! Last time I really struggled using the surface of the 3d mesh for the surface mesh, but the faces panel makes it super easy!

Still interested in all the other stuff I asked and how including the core in the laminate affects the calculation

Chris84

Does nobody know, if it makes a difference, if I set up my laminate from the inside out or from the outside inward in this case and if rounds are recommended here or if they're not necessary at all with composite analyses?