[Gmsh] use extruded lines to define new surfaces

Eric Nutsch ericnutsch at gmail.com
Sat Feb 20 08:25:50 CET 2010


Hi Julien,


I am having a similar problem. My goal is to create a boundary layer
of hexahedrals on an airfoil (Success!), then the fill the farfield
with tetrahedrals ( mesh is psudo2D; image attached).

I was not able to figure out a method to utilize an existing mesh to
direct the formation of another. My cfd tutor/professor said that this
is a common application and recommended that I locate a "mesh joining
command", but I have had no luck.

I speculate the desired utility would either convert such a mesh
boundary to geometry, utilize it as if it were geometry, or let you
set a Master/Slave configuration for duplicate meshing schemes within
the same volume.

For my application; It would be workable if the boundary layer simply
extruded geometry entities instead of mesh entities.


I will let you know if I make any progress,
Eric Nutsch



On Thu, Feb 18, 2010 at 11:32 AM, julien hoessler
<julien.hoessler06 at imperial.ac.uk> wrote:
> Good afternoon,
> I am trying to generate an hybrid mesh with a layer of prisms on a wall (one
> of the faces). I can find out using visibility/tree browser the id of the
> surfaces/lines generated by extrusion. Now I need to set up the faces on the
> borders of my domain that go between the edges of the extrusion and the
> opposite edges(the face on the foreground on the picture attached), but I
> can't use the extruded lines (cannot be selected). It makes sense since they
> are mesh lines rather than geometry lines, but is there any way to convert
> them into geometry lines? I could translate the lines but I'm using the
> extrude command to generate the prisms and the extrusion is normal to the
> surface so it won't match. I'm attaching a png image showing the lines of my
> extruded layer and the lines defining the remaining of the box. And if I set
> the lateral faces using the lines of the surface to be extruded, I obviously
> get to superposed meshes, 4 layers of quads and triangles connected to the
> same nodes
> Best regards
> Julien
>
>
> Julien Hoessler
> PhD Student
> Department of Aeronautics
> Imperial College London
>
> Phone: +44 (0) 20759 45042
> Email:   julien.hoessler06 at imperial.ac.uk
>
>
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