[Gmsh] Error transfinite volume
Christophe Geuzaine
cgeuzaine at ulg.ac.be
Fri Nov 7 17:02:51 CET 2008
Amit Itagi wrote:
> Christophe,
>
> Is it possible to include "progression" in the layers for the extrusion
> step ? Ultimately, that is what I want. Hence, I was avoiding
Hi - here's an example:
// the mesh nodes should match the points below
Point(1) = {0,0,0,1};
Point(2) = {1,0,0,1};
Point(3) = {3,0,0,1};
Point(4) = {7,0,0,1};
Point(5) = {15,0,0,1};
n = 4; // number of intervals
r = 2; // progression
// progression using transfinite mesh
Point(6) = {0,0.4,0,1};
Point(7) = {15,0.4,0,1};
Line(1) = {6,7};
Transfinite Line {1} = n+1 Using Progression r;
// progression using extruded mesh
a = (r - 1) / (r^n - 1);
one[0] = 1;
layer[0] = a;
For i In {1:n-1}
one[i] = 1;
layer[i] = layer[i-1] + a * r^i;
EndFor
Point(10) = {0,0.8,0,1};
Extrude {15,0,0} {
Point{10}; Layers{one[], layer[]};
}
> extrusion. If that is not possible, could you tell me that rule for the
> node ordering ?
>
> Thanks
>
> Rgds,
> Amit
>
>
>
> On Wed, Nov 5, 2008 at 2:08 PM, Christophe Geuzaine <cgeuzaine at ulg.ac.be
> <mailto:cgeuzaine at ulg.ac.be>> wrote:
>
> David Colignon wrote:
>
> Hi Amit,
>
> the ordering of the nodes in your "Transfinite Volume" commands
> is not correct. You should have:
>
> Transfinite Volume{233}={1,2,3,4,101,102,103,104};
> Transfinite Volume{235}={1,2,6,5,101,102,106,105};
> Transfinite Volume{237}={2,3,7,6,102,103,107,106};
> Transfinite Volume{239}={3,4,8,7,103,104,108,107};
> Transfinite Volume{241}={4,1,5,8,104,101,105,108};
>
>
> PS : for this kind of geometry it is probably simpler to use extrusion
>
>
> Point(1) = {-1,-1,0,0.2};
> Point(2) = {1,-1,0,0.2};
> Point(3) = {1,1,0,0.2};
> Point(4) = {-1,1,0,0.2};
> Line(1) = {1,2};
> Line(2) = {2,3};
> Line(3) = {3,4};
> Line(4) = {4,1};
> Line Loop(5) = {4,1,2,3};
> Plane Surface(6) = {5};
> Point(5) = {-5,-5,0,1};
> Point(6) = {5,-5,0,1};
> Point(7) = {5,5,0,1};
> Point(8) = {-5,5,0,1};
> Line(5) = {5,6};
> Line(6) = {6,7};
> Line(7) = {7,8};
> Line(8) = {8,5};
> Line(9) = {1,5};
> Line(10) = {2,6};
> Line(11) = {3,7};
> Line(12) = {4,8};
> Line Loop(13) = {1,10,-5,-9};
> Plane Surface(14) = {13};
> Line Loop(15) = {2,11,-6,-10};
> Plane Surface(16) = {15};
> Line Loop(17) = {3,12,-7,-11};
> Plane Surface(18) = {17};
> Line Loop(19) = {4,9,-8,-12};
> Plane Surface(20) = {19};
>
> Transfinite Line{1,2,3,4}=5;
> Transfinite Line{5,6,7,8}=5;
> Transfinite Line{9,10,11,12}=5 Using Progression 1.2;
>
> Transfinite Surface{6}={1,2,3,4};
> Transfinite Surface{14}={1,2,6,5};
> Transfinite Surface{16}={2,3,7,6};
> Transfinite Surface{18}={3,4,8,7};
> Transfinite Surface{20}={4,1,5,8};
>
> Recombine Surface{6,14:20:2};
> Extrude {0, 0, 10} {
> Surface{20, 18, 16, 14, 6}; Layers{5}; Recombine;
> }
>
>
> Cheers,
>
> Dave
>
>
>
> --
> Prof. Christophe Geuzaine
> University of Liege, Electrical Engineering and Computer Science
> http://www.montefiore.ulg.ac.be/~geuzaine
> <http://www.montefiore.ulg.ac.be/%7Egeuzaine>
>
>
>
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--
Prof. Christophe Geuzaine
University of Liege, Electrical Engineering and Computer Science
http://www.montefiore.ulg.ac.be/~geuzaine