# [Gmsh] Physical surface

David Colignon David.Colignon at ulg.ac.be
Tue Mar 2 15:50:44 CET 2010

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On 02/03/10 15:35, Alexis Blasselle wrote:
> I can't understand why my physical surface 22 is "unknown":

Hi Alexis,

just because you cannot extrude a "Physical" Surface, but only "geometrical" Surfaces ...

Regards,

Dave

>
> // exemple
>
> lc1 = 0.05 ;
> R = 0.5;
> H = 3 ;
>
> Point(100) = {0., 0., 0., lc1};
> // premier cercle
> Point(1) = {  0. ,  0. , -H/2 , lc1  } ;
> Point(2) = {  R  ,  0. , -H/2 , lc1  } ;
> Point(3) = {  0. ,  R  , -H/2. , lc1  } ;
> Point(4) = { -R  ,  0. , -H/2 , lc1  } ;
> Point(5) = {  0. , -R  , -H/2 , lc1  } ;
>
> Circle(23) = { 2 , 1 , 3 } ;
> Circle(34) = { 3 , 1 , 4 } ;
> Circle(45) = { 4 , 1 , 5 } ;
> Circle(52) = { 5 , 1 , 2 } ;
>
> Line Loop (1) = {23, 34, 45, 52 };
>
>
> out23[] = Extrude {0,0,-H} { Line{23}; };
> out34[] = Extrude {0,0,-H} { Line{34}; };
> out45[] = Extrude {0,0,-H} { Line{45}; };
> out52[] = Extrude {0,0,-H} { Line{52}; };
>
> Line Loop (2) = {out23[0], out34[0], out45[0], out52[0] };
> Plane Surface(1) = {2};
>
> Physical Surface(22) = {out23[1], out34[1], out45[1], out52[1], -1 };
>
> Translate {4., 0, 0} { Duplicata{ Surface{22}; } }
>
>
>
> Best regards,
>
> Miss Blasselle
> --
> http://www.ann.jussieu.fr/~blasselle/
>
>
>
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