Help selecting element- hyperelastic, adaptive meshing

[bues0022]

I need some help getting an element to work in my analysis. I am using a marlow hyperelastic material and am attempting to use ALE also. I can't seem to get any elements to work. I first attempted a brick element - C3D8R, and the error said that hyperelastic and hourglass control are not compatible. C3D8I error was that fully integrated elements won't work. I then tried tet - C3D4, but that one didn't work (can't remember error), and C3D10M didn't work - fully integrated elements won't work.

How do I either turn off hourglass control, or get an element to actually work? Thanks for the help.

 

[rstupplebeen]

I am assuming you are using Abaqus. You will probably get more help if you make that clear. Also, there is an Abaqus specific forum here. Please also post a simplified model to aide in the description and debugging.

http://www.eng-tips.com/threadminder.cfm?pid=799

Rob Stupplebeen

 

[jrw501]

Not sure if this helps, but I've used hyperelastic material models (Neo-Hookean and Mooney-Rivlin) with C3D8, C3D8H, C3D8I, elements before without issue.

 

[bues0022]

Sorry about the ambiguity. I wrote the question the other day in frustration and now realize that I didn't include many details. Yes, I am using ABAQUS. I'll get a simplified model posted soon. I am basically attempting to deform a piece of neoprene under a pressure load. I am using Marlow after going through the hyperelastic material evaluation. It fits best. Also, the problem isn't necessarily just using hyperelastic, but hyperelastic materials AND ALE. To make things even more confusing. Last night I was able to setup an explicit simulation, but used standard elements which seems like it essentially turned the simulation into a standard model instead. Does that sound right? It ran (mostly) but I was confused why that would actually work.

Mods, if you can move this into the ABAQUS forum I would appreciate it.

Thanks for the help, I'll get that file uploaded soon.

 

[bues0022]

Here's an input file that I generated that ran, but with ABAQUS standard C3D8R elements with Relax Stiffness for the hourglass control. This file was ran on my laptop, so the mesh is fairly coarse. I'd like to get it to run on the large servers, but their machines for some reason don't like the exact same file. Still looking into that one. I'd also like to run it as Explicit to compare the results (I think I'm going to get better results with Explicit actually, but we'll see). Any thoughts are greatly appreciated!