In this example we are going to use t6.geo, which we will edit slightly.
All alterations are mentioned below the sample code:
t6.geo
Include "t1.geo";
Delete{ Surface{1}; Curve{4}; }
p1 = newp; Point(p1) = {-0.05, 0.05, 0, lc};
p2 = newp; Point(p2) = {-0.05, 0.1, 0, lc};
l1 = newl; Line(l1) = {1, p1};
l2 = newl; Line(l2) = {p1, p2};
l3 = newl; Line(l3) = {p2, 4};
Curve Loop(2) = {2, -1, l1, l2, l3, -3};
Plane Surface(1) = {-2};
Transfinite Curve{2} = 20 Using Bump 0.25;
Transfinite Curve{l1} = 6;
Transfinite Curve{l2} = 6;
Transfinite Curve{l3} = 10;
Transfinite Curve{-1,3} = 30 Using Progression 1.05;
Transfinite Surface{1} = {1,2,3,4};
Recombine Surface{1};
Mesh.Smoothing = 100;
/* * * * * * * * * * * *
* Dolfyn added lines: *
* * * * * * * * * * * */
// Making a volume
Extrude {0,0,0.01} {Surface{1}; Layers{1}; Recombine; }
// Boundaries (non-default)
Physical Volume ("Fluid") = {1} ;
Physical Surface("Top") = {17};
Physical Surface("Left") = {29,25,21};
Physical Surface("Right") = {37};
Physical Surface("Bottom") = {33};
Physical Surface("Front") = {38};
Physical Surface("Back") = {1};Note
We edited the following (line numbers according to original document):
- line 27 – Changed the refinement to
0.25, to make it more subtle - line 38 – Changed the refinement to
1.05, to make it more subtle - Commented out lines:
- line 55-73 – we don’t need the second surface and we will define our own Physical instances
- Added lines (important!):
- line 81 – Added an extrude to create a volume
- line 85-92 – defined a new Physical Volume and Physical Surfaces
Visually the model will look like this:
Lastly, the t6d.din file.
> See the DINGuide (on the Downloads page) for reference.
t6d.din
title Test Gmsh t6.geo model
steps 50 1.e-3
opendx off
use gmsh fluid
pref,10
solver,w,off
density,1.2
vislam 120.e-6
boundary,left
wall
noslip
0.0 0.0 0.0
adiabatic
boundary,right
wall
noslip
0.0 0.0 0.0
adiabatic
boundary,front
symp
boundary,back
symp
boundary,top
inlet
0.0 -0.1 0.0
1.2
293
inle
0.05 0.01
boundary,bottom
outlet
1.0Again use gmsh fluid is used (line 6), to produce a full *.msh file, but ommitting the results on the boudaries.