Learning Forum

[KulTigin]

I want to prepare Explicit Dynamics Simulation for tensile specimen which manufactured with lattice structures. I created my geometry with lattice structures commands in SpaceClaim. The program creates surface geometries ,so i convert geometry solid firstly. My problem starts here. I don't use lattice optimization for this project. I meshed this geometry but there was a problem in solution. It could not be solved. So i tried element numbers. I think the smartest solution for this problem , modelling this geometry with shell or beam elements, but two cylinders are solid ,lattice structures are surface. So it can not be solved with explicit dynamics. I am waiting your help for my problem. 

[jj77]

If the lattice is thin, then definitely shells could be a good option.

 

If one looks around in the internet there will be mention that shells can be used with ansys explicit (autodyn). Sure if you look in the help you will find this.

[KulTigin]

jj77 thanks for your answer. Lattice structures are surface but cylinders are solid.Explicit can not be possible with shell and solid bodies. I have to find new solutions for this problem. I have two questions in my mind .

1- Am I right because of shell modelling to lattice structures?

2-If I don't right, are there any solution for meshing lattice structures?

[jj77]

I am not sure that one cannot run both solids and shells at the same model. I would try that and if it does not work, then:

1: Model the lattice then as a solid (3D elements), or skip the solid parts and apply loads straight on surface lattice, since the solid parts are very stiff (not sure if this is possible).

 

 

[KulTigin]

I tried run both shell and solid bodies at the same model but the program take an error about this situation. Lattice structure models can be very complex as in the attached files, meshing can be very hard. I found the mesh modul about this problem at the another program. It's working principle show in an attached files. I have to do in ANSYS what this module is doing.

[jj77]

The lattice as seen is solid not hollow so one would need solid elements to mesh, but I can appreciate that it can be hard to mesh.

 

 

[KulTigin]

Yes, it is my problem which you described your last sentence. It can be hard to mesh, so I have searched another way to solve it.

[sathya]

Hi,

If possible create shell coating with SURF154 with ~0mm thickness at solid-shell intersection. 

[aamer111]

What method you used to solve your problem? I have had a similar problem but still struggling with it.n

[zain1234]

Do i need to convert the facets into solids that were generated through shell to easily mesh in the analysis part? Please need urgent advisen

[fish leg]

Hello All,

 

I am a bit new to ansys and I tried to mesh lattice structure just to see its effect for tensile test. But it keeps failing. I will greatly appreciate it if you help me with this.

 

Regards

[peteroznewman]

This geometry is so complex that even after you get a valid mesh, you will not be able to solve it because the node and element count will exceed the allowable limit of the Student license.