Cubit Boundary Conditions

[Maria Sasso]

Hi all,

I have drown up a cantilever beam in Cubit, but I am afraid that I haven't assigned the proper BC to it because MoFEM gives me errors with convergence. I dunno if it may be best to apply forces or displacements? or if I have even fixed the structure properly.

I have attached the file. Anyone could help?

Cheers,
MS

[Karol Lewandowski]

Hi Maria,

Which user module is that? If elasticity then you need to create block with material parameters. 

type this in journal and execute.

block 1 volume all
block 1 name "MAT_ELASTIC"
block 1 attribute count
block 1 attribute index 1 5000
block 1 attribute index 2 0.3

In your model you forgot to fix the body in space, therefore we can see rigid body motion and displacements go to infinity. 

try this:

create displacement on surface 19 dof all fix

If you are not using journal in Cubit yet, I strongly recommend you to do so. If you need any help with that or a little tutorial I'd happy to help.

You can always find me in the postgrad room o level 6 in Rankine building,

Cheers

[Maria Sasso]

Hi Karol,

I will try this. 

I had avoided using the Jounal because I'm really quite lost with it so I was using the built in tools to assign constraints and forces.
I actually thought I had fixed the back of the beam.

I am sadly out of the country until the 22nd. I will try youtube for now then.

Thank you Karol!