# [Gmsh] Problem extruding surfaces.

Christophe Geuzaine cgeuzaine at ulg.ac.be
Wed Feb 24 13:25:20 CET 2010

```On 03/10/09 14:14, Billy Araujo wrote:
> I have the following geometry and I can't seem to extrude the surfaces.
>
> lc = 0.004;
>
> Point(1) = { 0.00, 0.01, 0.00, lc};
> Point(2) = {-0.04, 0.01, 0.00, lc};
> Point(3) = {-0.04,-0.01, 0.00, lc};
> Point(4) = { 0.00,-0.01, 0.00, lc};
> Point(5) = { 0.00, 0.05, 0.00, lc};
> Point(6) = { 0.00,-0.05, 0.00, lc};
> Point(7) = { 0.15, 0.05, 0.00, lc};
> Point(8) = { 0.15,-0.05, 0.00, lc};
> Point(9) = { 0.15, 0.01, 0.00, lc};
> Point(10)= { 0.15,-0.01, 0.00, lc};
>
> Line(1) = {1,4};
> Line(2) = {4,3};
> Line(3) = {3,2};
> Line(4) = {2,1};
> Line(5) = {1,5};
> Line(6) = {5,7};
> Line(7) = {7,9};
> Line(8) = {9,10};
> Line(9) = {10,8};
> Line(10) = {8,6};
> Line(11) = {6,4};
> Line(12) = {4,10};
> Line(13) = {9,1};
>
> Transfinite Line {5,11,7,9} = 8+1 Using Progression 1;
> Transfinite Line {1,3,8} = 4+1 Using Progression 1;
> Transfinite Line {2,4} = 8+1 Using Progression 1;
> Transfinite Line {6,10,12,13} = 30+1 Using Progression 1;
>
> Line Loop(14) = {4,1,2,3};
> Plane Surface(15) = {14};
> Line Loop(16) = {5,6,7,13};
> Plane Surface(17) = {16};
> Line Loop(18) = {12,-8,13,1};
> Plane Surface(19) = {18};
> Line Loop(20) = {9,10,11,12};
> Plane Surface(21) = {20};
>
> Transfinite Surface {17} = {1,5,7,9};
> Transfinite Surface {19} = {1,9,10,4};
> Transfinite Surface {21} = {4,10,8,6};
> Transfinite Surface {15} = {4,3,2,1};
> Recombine Surface {17,19,21,15};
>
> Extrude {0,0,0.002} {
>    Surface{17,19,21,15};
> }
>
> The extrusion doesn't give an error message but the geoemtry is damaged.

Hi Billy - in what sense? It seems ok over here: to generate the 3D mesh
I used

Extrude {0,0,0.002} { Surface{17,19,21,15}; Layers{3}; Recombine; }

>
> Billy.
>
> _______________________________________________
> gmsh mailing list
> gmsh at geuz.org
> http://www.geuz.org/mailman/listinfo/gmsh
>
>

--
Prof. Christophe Geuzaine
University of Liege, Electrical Engineering and Computer Science
http://www.montefiore.ulg.ac.be/~geuzaine

```