Suppressing elements with stress singularity in post result file

[adnanh]

Hi,

I am having frequently the problem of high stress concentrations. It has nothing to do with boundary conditions, it's the presence of sharp corners and sharp edges that causes the problem. Applying rounding features does not help. I have also tried to use options like "Detailed fillet modeling" and "Reentrant corners" but this neither helps. In the stress fringe plot I observe very large stress gradients which tell me that the high stresses on an edge or on a corner can never be right. Since these high stresses are just incorrect numerical values which impossibly can be resolved by the p-mesh, I would like to exclude them from the stress plot.

Is there a way to do this?

Regards,

Adnan

 

[adnanh]

Hi,

I also have some other questions:

1. Is it possible to visualize the nodes of elements? I usually inspect the automatically created mesh by observing the elements, but I would also like to see the nodes and their locations across the (edges of) elements.

2. Is it possible to refine the mesh locally manually at specific locations manually, for example fillets and roundings. I have read that there is a possibility but I can not find any step-by-step intructions for this.

Thanks in advance!

 

[ygagnon]

Hi;

In my experience with Pro.mech I have not found a way to exclude singularities; other than adjusting the VM fringe plot scales to a lower range. If its a large displacements (non linear you can use the exclude elements option) but that's about it.

Now for the questions that I can help.

1. Mechanica does not allow you to see the nodes, or get any nodal plots for that matter. It would be too useful wouldn't it?

2. There are a couple of options to refine your mesh. You can do so 'globally' by selecting Autogem > Settings > limits and modifying the edge max/edge min face max/face min values. Range vary from Plus or minus 4 around the medians (175 and 5) and the total must always adds to 180. eg. default values are 175 and 5 = 180. If you want to refine the mesh you can do 175-4= 171 and 5+4 = 9 = 180 on both edge and face inputs. Clear as mud?
I found a useful book that explains the process called: Mechanica "Element and Applications" part 1 (SDC pro publisher).

if you need to refine your mesh 'locally' you can use Autogem control. Here you will have to create volume, surface or edges; and set the element size. It's more user friendly that the previous one.