[Gmsh] Apply "refine by splitting" to a single transfinite surface

[Max Orok]

Hello Aaron,

This is kind of a dumb way, but taking your question literally, I made two
separate mesh files, refining just one and then merged them with these geo
commands:

Merge "mesh1.msh";
Merge "mesh2.msh";

This method however discards the geometry. The weird part is at the
boundary between the two; what should happen there for flow simulations,
etc?

[image: image.png]

Personally, for a real problem I would either increase the transfinite
resolution on the lines I wanted to be more refined or add a size field
(area with a different mesh refinement). The documentation has more
information on these options. Perhaps using mesh partitions could work as
well? I'm not really sure what those are to be honest but it sounds like
similar idea.

Sincerely,
Max



On Tue, Mar 5, 2019 at 4:06 PM Aaron Matthew Baier-Reinio <
ambaierreinio at edu.uwaterloo.ca> wrote:

> Hello,
>
> In the following toy example I have two adjacent squares, which are meshed
> using the transfinite algorithm:
>
> Point(1) = {0, 0, 0, 1.0};
> Point(2) = {1, -0, 0, 1.0};
> Point(3) = {1, 1, 0, 1.0};
> Point(4) = {0, 2, 0, 1.0};
> Point(5) = {0, 1, 0, 1.0};
> Point(6) = {1, 2, 0, 1.0};
>
> Line(1) = {4, 5};
> Line(2) = {5, 1};
> Line(3) = {1, 2};
> Line(4) = {3, 2};
> Line(5) = {3, 6};
> Line(6) = {6, 4};
> Line(7) = {5, 3};
>
> Curve Loop(1) = {1, 7, 5, 6};
> Plane Surface(1) = {1};
> Curve Loop(2) = {7, 4, -3, -2};
> Plane Surface(2) = {2};
>
> Transfinite Curve {6, 5, 7, 1, 4, 3, 2} = 10 Using Progression 1;
> Transfinite Surface {1};
> Transfinite Surface {2};
>
> When I press "refine by splitting", the number of elements in each square
> is doubled. I was wondering if there is a way to apply "refine by
> splitting" to the top square only, so that the number of elements in the
> top square is doubled, while the number of elements in the bottom square
> doesn't change. How might I go about doing this?
>
>
> Thanks for the help,
> Aaron
>
>
> _______________________________________________
> gmsh mailing list
> gmsh at onelab.info
> http://onelab.info/mailman/listinfo/gmsh
>


-- 
Max Orok
Contractor
www.mevex.com
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://onelab.info/pipermail/gmsh/attachments/20190306/9abf5da1/attachment-0001.html>
-------------- next part --------------
A non-text attachment was scrubbed...
Name: image.png
Type: image/png
Size: 18316 bytes
Desc: not available
URL: <http://onelab.info/pipermail/gmsh/attachments/20190306/9abf5da1/attachment-0001.png>