# [Gmsh] Meshing two volumes inside one another

Christophe Geuzaine cgeuzaine at ulg.ac.be
Wed Jan 28 21:03:24 CET 2015

```> On 13 Jan 2015, at 12:18, Shawn Nipun <shawn.3531 at gmail.com> wrote:
>
> Hello Sir,
>          I am suffering a little bit problem. I am trying mesh an structure using the following code. Here, there is an small volume which is indicated by volume 2 inside another volume indicated by  volume 1. The plane surfaces 34 and 36 of volume 2 are coincide with the the plane surfaces of  47 and 49 of volume 1. Problem is when I am doing the 3d mesh, it can be seen that only the surfaces of volume 1 are meshing, not the whole volume.
>

Your definition of Volume(1) is wrong: it should be

Surface Loop(46) = {47, 51, 57, 49, 53, 42, 38, 44, 40, 55};
Volume(1) = {46};

> // Gmsh project created on Mon Jan 12 14:22:18 2015
> nm = 1e-06;
> e1 = 4.5 * nm; e2 = 6 * nm / 2; e3 =  5 * nm / 2;
> l1 = 20 * nm;
> h1 = 4 * nm; h2 = 22 * nm; h3 = 14 * nm; h4 = 20 * nm; h5 = 4 * nm;
> R1 = 10 * nm; R2 = 2 * nm; R3 = 8 * nm;
> Lc1 = 0.000001;
> Lc2 = 0.0000005;
> Lc3 = 0.000001;
>
>
> // Si substarte
> Point(1) = {-e1-e2, 0    , 0, Lc1};
> Point(2) = {e1+e2, 0  , 0, Lc1};
> Point(3)= { e1+e2,  -l1  , 0, Lc1};
> Point(4)= {-e1-e2, -l1 , 0, Lc1};
> Point(5) = {-e1-e2, 0    , h1, Lc1};
> Point(6) = {e1+e2, 0  , h1, Lc1};
> Point(7)= { e1+e2,  -l1  , h1, Lc1};
> Point(8)= {-e1-e2, -l1 , h1, Lc1};
>
> Line(1) = {1, 2};
> Line(2) = {2, 3};
> Line(3) = {3, 4};
> Line(4) = {4, 1};
> Line(5) = {1, 5};
> Line(6) = {5, 6};
> Line(7) = {6, 2};
> Line(8) = {6, 7};
> Line(9) = {7, 8};
> Line(10) = {8, 5};
> Line(11) = {4, 8};
> Line(12) = {3, 7};
>
> // SiO2 layer
> Point(9) = {-e1-e2, 0  , h1+h2  , Lc1};
> Point(10) = {e1+e2, 0   , h1+h2  , Lc1};
> Point(11) = {e1+e2, -l1  , h1+h2  , Lc1};
> Point(12) = {-e1-e2, -l1   , h1+h2  , Lc1};
> Line(13) = {5, 9};
> Line(14) = {9, 10};
> Line(15) = {10, 6};
> Line(16) = {10, 11};
> Line(17) = {11, 12};
> Line(18) = {12, 9};
> Line(19) = {7, 11};
> Line(20) = {8, 12};
>
> // Cu layer
> Point(13)= {-e3, 0 , h1+h3, Lc2};
> Point(14)= {e3, 0 , h1+h3, Lc2};
> Point(15)= {-e3,  -l1, h1+h3, Lc2};
> Point(16)= {e3, -l1 , h1+h3, Lc2};
> Point(17)= {-e3, 0 , h1+h4, Lc2};
> Point(18)= {e3, 0 , h1+h4, Lc2};
> Point(19)= {-e3,  -l1, h1+h4, Lc2};
> Point(20)= {e3, -l1 , h1+h4, Lc2};
> Line(21) = {13, 14};
> Line(22) = {14, 18};
> Line(23) = {18, 17};
> Line(24) = {17, 13};
> Line(25) = {14, 16};
> Line(26) = {16, 15};
> Line(27) = {15, 13};
> Line(28) = {18, 20};
> Line(29) = {20, 19};
> Line(30) = {19, 17};
> Line(31) = {16, 20};
> Line(32) = {15, 19};
>
> Line Loop(33) = {23, 24, 21, 22};
> Plane Surface(34) = {33};
> Line Loop(35) = {29, -32, -26, 31};
> Plane Surface(36) = {35};
> Line Loop(37) = {22, 28, -31, -25};
> Plane Surface(38) = {37};
> Line Loop(39) = {24, -27, 32, 30};
> Plane Surface(40) = {39};
> Line Loop(41) = {21, 25, 26, 27};
> Plane Surface(42) = {41};
> Line Loop(43) = {23, -30, -29, -28};
> Plane Surface(44) = {43};
> Surface Loop(45) = {44, 34, 40, 42, 38, 36};
> Volume(2) = {45};
>
> //SiO2 volume define
> Line Loop(46) = {14, 15, -6, 13};
> Plane Surface(47) = {46,33};
> Line Loop(48) = {17, -20, -9, 19};
> Plane Surface(49) = {48,35};
> Line Loop(50) = {15, 8, 19, -16};
> Plane Surface(51) = {50};
> Line Loop(52) = {13, -18, -20, 10};
> Plane Surface(53) = {52};
> Line Loop(54) = {14, 16, 17, 18};
> Plane Surface(55) = {54};
> Line Loop(56) = {6, 8, 9, 10};
> Plane Surface(57) = {56};
> Surface Loop(46) = {47, 49, 51, 53, 55, 57,34,36};
> Volume(1) = {46};
>
> // Vacuum define
>
> Extrude {0, 0, .00001} {
>   Surface{55};
> }
> Physical Volume(300) = {3};
> Physical Volume(200) = {2};
> Physical Volume(100) = {1};
> Physical Surface(1) = {43};
> Physical Surface(2) = {87};
> Physical Surface(3) = {34, 36, 38, 40, 42, 44};
>
> Thanks and regards
> Shawn
>
>
> --
> Shawn Shakahwat Millat
> Master of Science in Nanoelectronics System
> Faculty of Electrical and Computer Engineering
> Dresden University of Technology
> Schnorrstarße 38, Room no: 0502
> 01069, Dresden
> Germany.
> _______________________________________________
> 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

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