[Gmsh] boundary layer in a 2D geometry

emmanuel.deltombe at free.fr emmanuel.deltombe at free.fr
Thu Nov 22 02:05:44 CET 2012


Hello,

I want to study a turbulent flow around a beam in 2D. I have installed Elmer on my Ubuntu 12.04 configuration,
as well as Gmsh.
I am creating the 2D geometry and mesh with gmsh but I can't be able to create a boundary layer.

I open my .geo file in Gmsh GUI, click on Mesh > 1D then 2D,
the mesh is created but not the boundary layer.

The script of the .geo file is not long :

cl1 = 0.02;
cl2 = 0.1;
Point(1) = {0, 0, 0, cl1};
Point(2) = {0.3, 0.3, 0, cl1};
Point(3) = {0.25, 0.35, 0, cl1};
Point(4) = {-0.05, 0.05, 0, cl1};
Point(5) = {-2, -0.7, 0, cl2};
Point(6) = {1, -0.7, 0, cl2};
Point(7) = {1, 1, 0, cl2};
Point(8) = {-2, 1, 0, cl2};
Line(1) = {1, 2};
Line(2) = {2, 3};
Line(3) = {3, 4};
Line(4) = {4, 1};
Line(5) = {5, 6};
Line(6) = {6, 7};
Line(7) = {7, 8};
Line(8) = {8, 5};
Line Loop(11) = {5, 6, 7, 8, -4, -3, -2, -1};
Plane Surface(11) = {11};
Physical Line(13) = {1, 2, 3, 4};
Physical Line(14) = {6};
Physical Line(15) = {8};
Physical Line(16) = {5, 7};
Physical Surface(12) = {11};
Field[1] = BoundaryLayer;
Field[1].EdgesList = {1, 2, 3, 4};
Field[1].NodesList = {1, 2, 3, 4};
Field[1].hfar = 0.05;
Field[1].hwall_n = 0.02;
Field[1].hwall_t = 0.003;
Field[1].ratio = 1.1;
Field[1].thickness = 0.01;

I read the FAQ, the screencasts and the Gmsh reference manual,
and didn't find the answer.
Is it a bug ?
I would be very grateful if anybody can help me,

Emmanuel