How to extract the Best middle surface

Hello friends

I would like to know if anybody knows how or what is the best combination or configuration to obtain the best Middle surface in Hypermesh, in order to work later meshing this new surface preferently in Quads with 5-6 size.

Thanks and regards

Find more posts tagged with

English

HyperMesh

Accepted answers

All comments

Pranav Hari

It depends on the type and complexity of the geometry. You can share the model or any images for better understanding.

Have a check at these generic videos on Midsurface creation.

https://www.youtube.com/watch?v=dVhdewZupGs

https://www.youtube.com/watch?v=WQr9huW_TEI

QuyNguyenDai

No general method for every geometry.

Altair Forum User

Geometry is complex with curves and edges, but I have the criteria necesary to obtain and adjust to it, for example:

# Criterion On Wt Ideal Good Warn Fail Worst Solver

0 penalty value 0.00 0.00 0.80 1.00 10.00
1 min length 1 1.0 5.00 4.00 3.80 3.50 3.00 0
2 max length 1 1.0 5.00 6.00 6.50 7.00 7.50
3 aspect ratio 1 1.0 1.00 2.50 3.50 5.00 9.50 12
4 warpage 1 1.0 0.00 1.00 2.00 5.00 9.50 12
5 max angle quad 1 1.0 90.00 105.00 123.00 135.00 142.50 0
6 min angle quad 1 1.0 90.00 75.00 57.00 45.00 37.50 0
7 max angle tria 0 1.0 60.00 76.66 103.30 110.00 135.00 0
8 min angle tria 1 1.0 60.00 45.00 35.00 20.00 10.00 0
9 skew 1 1.0 0.00 10.00 15.00 20.00 33.00 12
10 jacobian 0 1.0 1.00 0.90 0.70 0.60 0.30 0
11 chordal dev 0 1.0 0.00 0.30 0.80 1.00 2.00
12 % of trias 1 1.0 0.00 2.00 4.00 4.90 5.00

Is there some automatic tool to create it or have the best mesh adapted to it?

thanks in advance...

QuyNguyenDai

These criterion are for FE mesh, not for mid-surface (geometric entity).

Pranav Hari

Hi Curro Capi de Camas

As Q.Nguyen-Dai mentioned, the parameters you mentioned above are for checking the quality of FE Mesh

Is there some automatic tool

However, check whether these TCL scripts can help you.

This Scripts can be used for Structures, where each Component represents one sheet metal part of uniform thickness. For each Component one midsurface component and one associated property will be created. The comp/prop names use the volume components name following a thickness string.
The assembly hierarchy of the solid model is mirrored for the midsurface model.

This script checks the displayed elements for quality. the checks are the standard checks of the check elements panel. threshold values are set in script
failed elements are put into sets element and node sets

Unable to find an attachment - read this blog

Altair Forum User

Hi Curro Capi de Camas

As Q.Nguyen-Dai mentioned, the parameters you mentioned above are for checking the quality of FE Mesh

However, check whether these TCL scripts can help you.

This Scripts can be used for Structures, where each Component represents one sheet metal part of uniform thickness. For each Component one midsurface component and one associated property will be created. The comp/prop names use the volume components name following a thickness string.
The assembly hierarchy of the solid model is mirrored for the midsurface model.

This script checks the displayed elements for quality. the checks are the standard checks of the check elements panel. threshold values are set in script
failed elements are put into sets element and node sets

Thanks a lot for your quick reply and help

I will try.... and let you know

FE

Unable to find an attachment - read this blog

Altair Forum User

Hello Pranav Hari,

Thanks for the TCL scripts.

I don´t understand exatly the ''. My idea is to define a good middle surface geometry in order to mesh it later. The middle surface is not bad with yout TCL '' but the problem is when I need to get meet the mesh criteria fullfiled like the photo attached.

Is there any automatic tool like TCL that can help to do it? In 2D/Quality Index/Cleanup tools there are some options to repair it manually...

Regards

<?xml version="1.0" encoding="UTF-8"?>

Unable to find an attachment - read this blog

Pranav Hari

Is there any automatic tool like TCL that can help to do it? In 2D/Quality Index/Cleanup tools there are some options to repair it manually...

Hi Curro Capi de Camas

As you mentioned, since you need to check the mesh quality for different quality criterion, then the can help you.

Instead of setting the quality criterion manually in HM, you can set it in the script (edit the script with your quality parameters) and the script automatically stores the failed elements in sets.

<?xml version="1.0" encoding="UTF-8"?>

Unable to find an attachment - read this blog