ABAQUS RIGID PART VS RIGID SHELLS

[cd5486]

I am simulating some assembly, where I have found out that, converting deformable parts to rigid parts have no effect(negligible) to the results I want to extract. I wanted to know, if rather converting deformable parts to rigid body, I can convert them also to rigid shell or surface and transfer mass and inertia properties.

The thinking to convert rigid body to rigid shell, lies in the fact that doing that would reduce elements, making smaller matrices and hence reduced simulation time. Would this work?

I am running the simulation in Abaqus Explicit.

 

[FEA way]

Yes, in most cases you can do it if you make sure that proper point mass/inertia is applied to the reference point of a rigid body.

 

[cd5486]

Any advice on how to go about it..

As in to use shells or surface elements ?

And How much performance improvement will be there, from converting rigid part to rigid shell ?

Thanks in advance.

 

[FEA way]

You can use Shape --> Shell --> From Solid to convert a solid part to a shell. Then change its type to rigid and discrete rigid elements will be automatically assigned to it.

Actually, it is best to use analytical rigid parts whenever possible because they are much more efficient than discrete rigid ones. But in many cases, it can't be done due to the complex geometry of rigid parts. It's hard to say what will be the difference in analysis time between a rigid part modeled as deformable solid with rigid body constraint applied to it and the same part modeled as discrete rigid and thus having a form of a shell. It would be best to make a simple test for your particular case and compare the performance if you are concerned about that.