Odd Shaped Volume Mesh

[Anonymous]

Hello,

I have a little bit of trouble getting a regular volume mehs.

Or maybe my understanding of the meshing algorithm is not the best.

I have attached a PDF with two samples of my problem.

the survece mesh looks very good, and most part of the internal mesh, too.

But without an obvious reason the internal mesh is highly distorted in some areas.

If there was any kind of corner or irregularity in the part, I could understand that.

But with e.g. two parallel surfaces I do not see, why the intenal mesh is discretized so irregular.

I have tried the options, described in:

http://wikihelp.autodesk.com/Autodesk_Simulation/enu/2012/Help/0113-Mesh_Mod113/0114-Mesh_Ove114/011...

But with no notable results.

Has anyone a hint in which way to proceed with the optimization or is this normal.

Even if there is no effect on the results, the calculation time does increase because of the additional elements...

Regards

Boris

tried so far:

• Microholes on/off
• Mehs type (layered mesh of thin parts works, but obviously only for thin parts...)
• aspect ratio
• warp angle
• volume-to-length ratio
• midside nodes

[SaMurgie · Accepted solution]

Hi Boris

This is normal and as expected with our meshing algorithm.  We start on the outside and work our way inwards eventually needed to fill irregular shapes caused by the various advancing fronts.

Note this is fine for structural analysis where all areas of interest are on the outside (for the most part).

Allowing microholes will generate less of these irregular shaped elements.

Of course, having a fine mesh will also yield a better looking mesh in the interior (of course, at the expense of solve time).

If regularly shaped elements are needed (eg fluid flow), then I recommend using tetrahedral elements as that will yield a better internal mesh in most cases.

Regards,
Sam