# [Gmsh] Mesh generation error because of rotational extrusion?

Bart Deschoolmeester bart.deschoolmeester at bbri.be
Sat Aug 15 12:26:18 CEST 2020

```Hi all,
See the line (below):
Extrude {{0, 0, 1}, {0, 0, 0}, 1.4*Pi} {
Surface{8}; Layers {25};
}

Changing 1.4 to 1.5: gives errors.
Extrude {{0, 0, 1}, {0, 0, 0}, 1.5*Pi} {
Surface{8}; Layers {25};
}

Am I doing something wrong?

Bart
-----------------------

KanR = DefineNumber[ 0.1, Name "Parameters/KanR" ];
WanD = DefineNumber[ 0.2, Name "Parameters/WanD" ];
KanMeshsize = DefineNumber[ 0.01, Name "Parameters/KanMeshsize" ];
Rectangle(1) = {-2.5, -2.5, 0, 5, 5, 0};
Circle(5) = {0, 0, 0, KanR, 0, 2*Pi};
Curve Loop(2) = {5};
Plane Surface(2) = {2};
BooleanDifference{ Surface{1}; Delete; }{ Surface{2}; Delete; }
Extrude {0, 0, WanD } {
Surface{1};
}
Point(15) = {0, KanR, 0};
Point(16) = {0, KanR-0.05, 0};
Point(17) = {0, KanR-0.05, WanD};
Point(18) = {0, KanR, WanD};
Line(20) = {15, 16};
Line(21) = {16, 17};
Line(22) = {17, 18};
Line(23) = {18, 15};
Curve Loop(24) = {20, 21, 22, 23};
Plane Surface(8) = {24};
Extrude {{0, 0, 1}, {0, 0, 0}, 1.4*Pi} {
Surface{8}; Layers {25};
}

Field[1] = Distance;
Field[1].EdgesList = {5};
Field[1].NNodesByEdge = 50;
Field[2] = Threshold;
Field[2].DistMax = 2.5;
Field[2].DistMin = 0;
Field[2].IField = 1;
Field[2].LcMax = 0.25;
Field[2].LcMin = KanMeshsize ;

Background Field = 2;

Mesh.CharacteristicLengthExtendFromBoundary = 0;
Mesh.CharacteristicLengthFromPoints = 0;
Mesh.CharacteristicLengthFromCurvature = 0;
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://onelab.info/pipermail/gmsh/attachments/20200815/b7f18e35/attachment-0001.html>
```