Wrong mesh made by Body Fitting Algo

Hi,

I try to mesh a hexahedral solid by using the method Body Fitting. So that I can obtain a mesh of Cartesien (la Boite a Sucre). Everything is OK and the mesh computation is succeeded. But the result is so strange (shown in the attachment). I don't know why the edges are like sawtooth but not just a line!

I attach the geometrical view of my solid in the second reply, and here's the link to download all my shapes for someone who may want to do some experiments:

https://filex.insa-rouen.fr/get?k=k7BUrmOnZUtlvJorli9

The objets that should be meshed are named "Solid_1, _3, _4" and "Solid_5". You can mesh anyone as you like. The result is the same for all of them. There's always a sawtooth in all the edges.

Any help will be appreciated!

Here's the view of the solid in GEOM module. (a hexahedral solid)

Regards

Hello,

You have to increase the threshold value. Any element size (area, edge length ? I don't know) below this value will be removed.

Regards,

Gilles

Previously DAVID Gilles wrote:

Hello,

You have to increase the threshold value. Any element size (area, edge length ? I don't know) below this value will be removed.

Regards,

Gilles

Hi Hao,
try to decrease Z spacing.

St.Michael

Previously Saint Michael wrote:

Hi Hao,
try to decrease Z spacing.

St.Michael

P.S. Something more about that picture attached, it was made by a size of 200*200*1. 

Hi Hao

Apparently your shapes are not suitable for Body Fitting algo. I think it's possible to make a hexahedral mesh using quadrangles already present in your shape. I can create a script doing this if it's OK for you.

St.Michael

Hi,

I've already tried to mesh my solid by Hexahedralization algorithm:

3D : Hexahedron (i,j,k)

2D : Quadrangle (Mapping)

1D: Wire discretisation

Hypothese for 1D: Nb. Segments = 2 OR Max Size = 78 OR Local Length = 200

All of this lead me to an error during the calculation as in this picture :

https://filex.insa-rouen.fr/get?k=1gr0AzlPUdObqlCITjH

       (↑sorry, I can't attach a file more than 100k in this forum.)

I don't know if this is the method that you want to try ? If so, well, at least the calculating is failed in my computer. If not, please show me your idea. 

Your shape is neither suitable for Hexahedron(i,j,k), which requires that a shape to be a 6-sided solid (box). Hexa(i,j,k) would work if you created boxes of your quadrangles when constructing your shape.

My idea is make a 2D mesh on your shape and then to find corresponding top and bottom quadrangles to make hexahedrons on them in a script.

St.Michael

Previously Saint Michael wrote:

Your shape is neither suitable for Hexahedron(i,j,k), which requires that a shape to be a 6-sided solid (box). Hexa(i,j,k) would work if you created boxes of your quadrangles when constructing your shape.

My idea is make a 2D mesh on your shape and then to find corresponding top and bottom quadrangles to make hexahedrons on them in a script.

St.Michael

Here is the script. On Solid_1.brep it create all but 2 prisms.

St. Michael