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problems with abaqus

problems with abaqus

problems with abaqus

(OP)

Attached is a video of my model as it is impacted by a rigid part. This is a bone impacted by an analytical rigid part.

There are three problems:

the analytical rigid part in the part module appears as a rectangle (which is how it is desired) however in the simulation (visualization module) it appears as a thin line (please watch the video). I would like to keep the original shape of this part...but how? and why does it change in the first place?

The second problem:
the rigid part is not making any contact with the bone, it just seems as if it is exerting a force toward the bone that causes the bone to deform but that is it. There is no actual contact! I applied a surface to surface contact, with a kinematic contact method, assuming it is frictionless.

Third problem:
the bone is bending too much! this is erraneous. I need to define a point at which elasticity of the bone no longer holds (I have defined elastic properties to the bone). How can i do this?

I will be immensely grateful for any help!
attached is the simulation video please check it out!!

RE: problems with abaqus

The rigid part looks rectangular to me, but if it's an illusion then maybe it's an analytical rigid part and needs to be swept in the odb viewer options.
Contact doesn't seem to be made as I'd expect high stresses at the contact points at the top and bottom of the rigid part. Check to make sure you've applied the right forces.
Can't help with the breaking point of the bone, sorry.  

ex-corus (semi-detached)

RE: problems with abaqus

I believe the issue is that you are animating a scale factor instead of the time steps.  I hope this helps.

Rob Stupplebeen

RE: problems with abaqus

The bone is bending too much because you probably only defined the elastic properties so Abaqus is going to extrapolate that Young's well past failure. You need to look into element deletion and a failure method like tensile or shear.

RE: problems with abaqus

Corus: where have you moved to?

RE: problems with abaqus

Following on from rstupplebeen's comment; I don't know if it's the poor graphics or not, but you seem to be showing the results at time 0.01 with a deformation factor of 1. Unless it's Mr Wobbly's bone, it seems to be a lot of deformation. I would check all your input, and consider using a lot more C3D10M tet elements for your model.

mrgoldthorpe,
Sadly not gone anywhere but ..

Hoping to say Tata  

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