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Aline July 2, 2004 10:57

Shell
 
I have done a patch and then I have extruded it. But now I want to define the boundaries, and I can not define any on the shell from the initial patch. What can I do?

Thanks.

StarCD July 2, 2004 11:43

Re: Shell
 
How did you extrude it?

As far as I know, shell type cell is used to define the patches, which are then converted to fluid or solid or whatever you need before any boundaries can be applied.

If you have 2D model, one way to extrude your geometry is to use 2D3D cartesian x... where x is the amount of extrusion.

This results in symmetry planes being automatically applied to the extrusion plane. Then you can aplly other boundaries wherever u like.

Hope this helps :)

StarCD

Aline July 2, 2004 11:56

Re: Shell
 
I have finally defined the boundaries, but the patch seems to create a discontinuity in the fluid cells. But perhaps it is normal. I will see if the resuls are coherent.

Thanks!

Aline

StarCD July 2, 2004 11:59

Re: Shell
 
Check cell aspect ratio and tolerance when you merge the vertices

Panos July 2, 2004 12:23

Re: Shell
 
Be also careful when you click on the cells for boundaries not to click twice because you will get errors in boundaries. For example if you have a symmetrical 3d model and inlet and oulet boundaries must be equal. Otherwise you will get the message "boundaries in the exterior not found". Before you apply the boundaries you have to change cell type to fluid type (1) in the STAR Guide.

4xF July 2, 2004 13:39

Re: Shell
 
A usefull command to create boundaries from defined shells is BSHELL (see also the online help for the use of this command).

Matej July 7, 2004 02:30

Re: Shell
 
Aline,

Forget what Panos says. It is completelly nonsense. (sorry to say so).

If you have discontinuity in the mesh, it is not because of shell cells. It is because your cells has separate vertices (points in cell corners) defined on the same place. What you have to do is to merge those vertices. Look in manuals for merging vertices.

matej


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