[Gmsh] voids adjacent to a volume edge

[Shawn Fostner]

Hi all,

A problem I thought I'd gotten around a while ago, but I guess not.

The geometry in question is a rectangular box (surface), with a second 
box immediately adjacent it (mostly empty space, but defines my meshing 
region). Now immediately above the surface there is a small region which 
I have been using to define a metal piece, it is entirely outside but 
just touching the surface (in the ideal case). Usually I use the metal 
as a void when I define the region above the surface (plus other 
objects, irrelevant here).

The problem is that if I don't leave a gap (even if tiny) between the 
metal and the surface then the 3d mesh invariably fails, but if I do 
leave a gap then it throws off the field calculation dramatically 
(because of small meshing volumes at the corner of that region). I can 
understand there would be a problem with a void that overlaps the 
boundary of a volume, or it might be because of the adjacent volume, but...

Now I guess I could deliberately eliminate any mesh elements in that gap 
between the void and surface, not sure how though. Otherwise, is there 
anything else I can try? Any suggestions would be great.

I've included a version of the geo file, ignore the extra structure. 
Currently there is a 0.01 unit gap between surface and metal (the object 
between surfaces 12 and 13.

Thanks!

Shawn

-------------- next part --------------
An embedded and charset-unspecified text was scrubbed...
Name: examplefile.geo
URL: <http://www.geuz.org/pipermail/gmsh/attachments/20091026/c399c0d2/attachment.geo>