[Gmsh] isotropic 3D algorithm fails

Ondrej Certik ondrej at certik.cz
Mon May 30 16:33:14 CEST 2005

```Hello,
part of a cylinder is a structured grid, the other part is made of unstructured
grid. The structured part meshes OK, the unstructured doesn't mesh at
all, but gmsh doesn't complain about anything.

Does anybody know where the problem could be?

Ondrej Certik

----------------------
t1.geo:

d=1000;
h=1000;
r= 700;
r0 = 100;
w=1000;
r1=2*r0;
l2=3;
l3=3;
lt=r0;
lc = 200;
grain=lc;
tip=grain;
bot=grain;
l1=5;
tx=r/Sqrt(2);
ty=r/Sqrt(2);

Point(1) = {0, 0, 0, bot};
Point(2) = {d, 0, 0, lc} ;
Point(3) = {d, h, 0, lc} ;
Point(4) = {0, h, 0, lc} ;
Point(5) = {0.000000*w, 0.100000*h, 0, tip};
Point(11) = {0.010000*w, 0.110000*h, 0, grain};
Point(12) = {0.020000*w, 0.126390*h, 0, grain};
Point(13) = {0.030000*w, 0.146555*h, 0, grain};
Point(14) = {0.040000*w, 0.169644*h, 0, grain};
Point(15) = {0.050000*w, 0.195183*h, 0, grain};
Point(16) = {0.060000*w, 0.222860*h, 0, grain};
Point(17) = {0.070000*w, 0.252453*h, 0, grain};
Point(18) = {0.080000*w, 0.283792*h, 0, grain};
Point(19) = {0.090000*w, 0.316740*h, 0, grain};
Point(20) = {0.100000*w, 0.351189*h, 0, grain};
Point(21) = {0.110000*w, 0.387045*h, 0, grain};
Point(22) = {0.120000*w, 0.424230*h, 0, grain};
Point(23) = {0.130000*w, 0.462678*h, 0, grain};
Point(24) = {0.140000*w, 0.502327*h, 0, grain};
Point(25) = {0.150000*w, 0.543127*h, 0, grain};
Point(26) = {0.160000*w, 0.585029*h, 0, grain};
Point(27) = {0.170000*w, 0.627993*h, 0, grain};
Point(28) = {0.180000*w, 0.671981*h, 0, grain};
Point(29) = {0.190000*w, 0.716957*h, 0, grain};
Point(30) = {0.200000*w, 0.762891*h, 0, grain};
Point(31) = {0.210000*w, 0.809753*h, 0, grain};
Point(32) = {0.220000*w, 0.857516*h, 0, grain};
Point(6) = {0.248821*w, 1.000000*h, 0, grain};
CatmullRom(7) = {5,11,12,13,14,15,16,17,18,19,20,21,22,23,24,25,26,27,28,29,30,31,32,6};

Line(1) = {1,2} ;
Line(2) = {3,2} ;
Line(3) = {3,6};
Line(4) = {6,4};
Line(5) = {4,5};
Line(6) = {5,1};
Line Loop(8) = {2,-1,-6,7,-3};
Plane Surface(9) = {-8};
Line Loop(10) = {7,4,5};
Plane Surface(11) = {10};
Recombine Surface(9);
Recombine Surface(11);

Extrude Surface {11, {0.0,1.0,0.0}, {0.0,0.0,0.0}, Pi*3/4}
{ Recombine; Layers {l1, 0, 1}; };
Extrude Surface {23, {0.0,1.0,0.0}, {0.0,0.0,0.0}, Pi*3/4}
{ Recombine; Layers {l1, 0, 1}; };
Extrude Surface {35, {0.0,1.0,0.0}, {0.0,0.0,0.0}, Pi/2}
{ Recombine; Layers {l1, 0, 1}; };
Extrude Surface {9, {0.0,1.0,0.0}, {0.0,0.0,0.0}, Pi*3/4}
{ Recombine; Layers {l1, 0, 1}; };
Extrude Surface {67, {0.0,1.0,0.0}, {0.0,0.0,0.0}, Pi*3/4}
{ Recombine; Layers {l1, 0, 1}; };

Point(7) = {tx, h, ty, lt};
Point(8) = {tx+r0, h, ty, lt};
Point(1000) = {tx+r1, h, ty, lt};

Line(80) = {7,8};
Line(81) = {8,1000};
Extrude Line {80, {0.0,0,1}, {tx,h,ty}, -Pi/2}
{ Recombine; Layers {l2, 0, 1}; };
Extrude Line {81, {0.0,0,1}, {tx,h,ty}, -Pi/2}
{ Recombine; Layers {l2, 0, 1}; };
Extrude Surface {92, {0,1,0}, {tx,h,ty}, Pi*2/3}
{ Recombine; Layers {l3, 0, 1}; };
Extrude Surface {108, {0,1,0}, {tx,h,ty}, Pi*2/3}
{ Recombine; Layers {l3, 0, 1}; };
Extrude Surface {120, {0,1,0}, {tx,h,ty}, Pi*2/3}
{ Recombine; Layers {l3, 0, 1}; };
Extrude Surface {96, {0,1,0}, {tx,h,ty}, Pi*2/3}
{ Recombine; Layers {l3, 0, 1}; };
Extrude Surface {147, {0,1,0}, {tx,h,ty}, Pi*2/3}
{ Recombine; Layers {l3, 0, 1}; };
Extrude Surface {164, {0,1,0}, {tx,h,ty}, Pi*2/3}
{ Recombine; Layers {l3, 0, 1}; };

Circle(177) = {117,4,3};
Circle(178) = {152,1,2};
Line Loop(179) = {1,-178,-72};
Plane Surface(182) = {179};
Recombine Surface(182);
Line Loop(183) = {177,3,-41,-69};
Line Loop(184) = {138,155,172};
Plane Surface(185) = {183,184};
Recombine Surface(185);
Line Loop(186) = {177,2,-178,73};
Ruled Surface(187) = {186};
Surface Loop(188) = {187,-185,9,-42,-89,-182,176,142,159};
Volume(189) = {188};

---------------------------------------
output of "gmsh t1.geo -3 -order 1":

Info    : 'gmsh t1.geo -3 -order 1 ' started on Mon May 30 16:29:58 2005
Info    : Parsing file 't1.geo'
Info    : Parsed file 't1.geo'
Info    : Mesh 1D...
Info    : Meshing curve 1
Info    : Meshing curve 2
Info    : Meshing curve 3
Info    : Meshing curve 4
Info    : Meshing curve 5
Info    : Meshing curve 6
Info    : Meshing curve 7
Info    : Meshing curve 13
Info    : Meshing curve 14
Info    : Meshing curve 17
Info    : Meshing curve 25
Info    : Meshing curve 26
Info    : Meshing curve 29
Info    : Meshing curve 41
Info    : Meshing curve 47
Info    : Meshing curve 50
Info    : Meshing curve 51
Info    : Meshing curve 53
Info    : Meshing curve 61
Info    : Meshing curve 69
Info    : Meshing curve 72
Info    : Meshing curve 73
Info    : Meshing curve 75
Info    : Meshing curve 80
Info    : Meshing curve 81
Info    : Meshing curve 83
Info    : Meshing curve 90
Info    : Meshing curve 91
Info    : Meshing curve 93
Info    : Meshing curve 95
Info    : Meshing curve 98
Info    : Meshing curve 99
Info    : Meshing curve 102
Info    : Meshing curve 110
Info    : Meshing curve 111
Info    : Meshing curve 114
Info    : Meshing curve 126
Info    : Meshing curve 132
Info    : Meshing curve 133
Info    : Meshing curve 138
Info    : Meshing curve 149
Info    : Meshing curve 150
Info    : Meshing curve 155
Info    : Meshing curve 172
Info    : Meshing curve 177
Info    : Meshing curve 178
Info    : Mesh 1D complete (0.025996 s)
Info    : Mesh 2D...
Info    : Meshing surface 9
Info    : Smoothing surface 9
Info    : Recombining surface 9
Info    : Meshing surface 11
Info    : Smoothing surface 11
Info    : Recombining surface 11
Info    : Meshing surface 18
Info    : Meshing surface 21
Info    : Meshing surface 23
Info    : Meshing surface 30
Info    : Meshing surface 33
Info    : Meshing surface 35
Info    : Meshing surface 42
Info    : Meshing surface 45
Info    : Meshing surface 55
Info    : Meshing surface 62
Info    : Meshing surface 66
Info    : Meshing surface 67
Info    : Meshing surface 77
Info    : Meshing surface 84
Info    : Meshing surface 88
Info    : Meshing surface 89
Info    : Meshing surface 92
Info    : Meshing surface 96
Info    : Meshing surface 103
Info    : Meshing surface 106
Info    : Meshing surface 108
Info    : Meshing surface 115
Info    : Meshing surface 118
Info    : Meshing surface 120
Info    : Meshing surface 127
Info    : Meshing surface 130
Info    : Meshing surface 139
Info    : Meshing surface 142
Info    : Meshing surface 147
Info    : Meshing surface 156
Info    : Meshing surface 159
Info    : Meshing surface 164
Info    : Meshing surface 173
Info    : Meshing surface 176
Info    : Meshing surface 182
Info    : Smoothing surface 182
Info    : Recombining surface 182
Info    : Meshing surface 185
Info    : Smoothing surface 185
Info    : Recombining surface 185
Info    : Meshing surface 187
Info    : Smoothing surface 187
Info    : Mesh 2D complete (0.059991 s)
Info    : Mesh 3D...
Info    : Mesh 3D... (initial)
Info    : Meshing volume 1
Info    : Meshing volume 2
Info    : Meshing volume 3
Info    : Meshing volume 4
Info    : Meshing volume 5
Info    : Meshing volume 6
Info    : Meshing volume 7
Info    : Meshing volume 8
Info    : Meshing volume 9
Info    : Meshing volume 10
Info    : Meshing volume 11
Info    : Swapping 0
Info    : Mesh 3D... (Final)
Info    : Meshing volume 1
Info    : Meshing volume 2
Info    : Meshing volume 3
Info    : Meshing volume 4
Info    : Meshing volume 5
Info    : Meshing volume 6
Info    : Meshing volume 7
Info    : Meshing volume 8
Info    : Meshing volume 9
Info    : Meshing volume 10
Info    : Meshing volume 11
Info    : Mesh 3D... (initial)
Info    : Nod=8/177 Elm=37
Info    : Vol=2.744e+09 (6 1 1)
Info    : Nod=16/177 Elm=72
Info    : Vol=2.744e+09 (14 1 1)
Info    : Nod=24/177 Elm=113
Info    : Vol=2.744e+09 (22 1 1)
Info    : Nod=32/177 Elm=147
Info    : Vol=2.744e+09 (30 1 1)
Info    : Nod=40/177 Elm=193
Info    : Vol=2.744e+09 (36 3 1)
Info    : Nod=48/177 Elm=246
Info    : Vol=2.744e+09 (42 5 1)
Info    : Nod=56/177 Elm=304
Info    : Vol=2.744e+09 (49 6 1)
Info    : Nod=64/177 Elm=347
Info    : Vol=2.744e+09 (54 9 1)
Info    : Nod=72/177 Elm=389
Info    : Vol=2.744e+09 (58 13 1)
Info    : Nod=80/177 Elm=424
Info    : Vol=2.744e+09 (65 14 1)
Info    : Nod=88/177 Elm=478
Info    : Vol=2.744e+09 (72 15 1)
Info    : Nod=96/177 Elm=532
Info    : Vol=2.744e+09 (78 17 1)
Info    : Nod=104/177 Elm=583
Info    : Vol=2.744e+09 (85 18 1)
Info    : Nod=112/177 Elm=637
Info    : Vol=2.744e+09 (91 20 1)
Info    : Nod=120/177 Elm=681
Info    : Vol=2.744e+09 (98 21 1)
Info    : Nod=128/177 Elm=730
Info    : Vol=2.744e+09 (104 23 1)
Info    : Nod=136/177 Elm=763
Info    : Vol=2.744e+09 (109 26 1)
Info    : Nod=144/177 Elm=811
Info    : Vol=2.744e+09 (117 26 1)
Info    : Nod=152/177 Elm=858
Info    : Vol=2.744e+09 (122 29 1)
Info    : Nod=160/177 Elm=903
Info    : Vol=2.744e+09 (129 30 1)
Info    : Nod=168/177 Elm=941
Info    : Vol=2.744e+09 (136 31 1)
Info    : Nod=176/177 Elm=988
Info    : Vol=2.744e+09 (143 32 1)
Info    : Swapped 2 edges
Info    : Swapped 0 edges
Info    : Boundary edges recovery
Info    : Volume = 2.744e+09
Info    : ===================================================
: Number of missing edges = 0
: ===================================================
Info    : Boundary faces recovery
Info    : Volume = 2.744e+09
Info    : ===================================================
: Number of missing faces = 0
: ===================================================
Info    : Volume after edge/face recovery = 2.744e+09
Info    : Final check: 0 missing edges, 0 missing faces
Info    : ===================================================
: Surface coherence results (number of intersections)
: 0 EV, 0 EE, 0 FV, 0 FF, 0 FE, 0 EEE, 0 EEEE
: ===================================================
Info    : Volume recovery
Info    : Surface 9
Info    : Surface 42
Info    : Surface 89
Info    : Surface 142
Info    : Surface 159
Info    : Surface 176
Info    : Surface 182
Info    : Surface 185
Info    : Surface 187
Info    : Mesh 3D complete (0.179973 s)
Info    : Writing mesh file 't1.msh'
Info    : Saving all elements (discarding physical groups)
Info    : 489 nodes
Info    : 1044 elements
Info    : Wrote mesh file 't1.msh'

```