In this example we are going to use man.geo.
In this file, you see that a *.stl file is imported. Furthermore, we build a structure around it to delimit our working volume, and function as a wind tunnel.
man.geo
Geometry.Tolerance = 1.e-6;
MeshSize = 2. ;
StdSize = 10. ;
// Note that importing a *.stl creates a Surface.
Merge "man_model.stl" ;
// Building wind tunnel
Point(1) = { 1.5 * StdSize,-13.0, 1 * StdSize, MeshSize};
Point(2) = {-1.5 * StdSize,-13.0, 1 * StdSize, MeshSize};
Point(3) = {-1.5 * StdSize,-13.0,-2 * StdSize, MeshSize};
Point(4) = { 1.5 * StdSize,-13.0,-2 * StdSize, MeshSize};
Line(1) = {1 , 2};
Line(2) = {2 , 3};
Line(3) = {3 , 4};
Line(4) = {4 , 1};
Line Loop(1) = {1, 2, 3, 4};
Plane Surface(2) = {1};
Extrude{0, 3.0 * StdSize, 0 }{ Surface{2}; }
Surface Loop(1) = {1};
Surface Loop(2) = { 2, 13, 17, 21, 25, 26};
// Define volume around man
Volume(2) = {2,1};
// Defining physical elements
Physical Volume("Fluid") = {2};
Physical Surface("Man ") = {1};
Physical Surface("Floor") = {2};
Physical Surface("Inlet") = {13};
Physical Surface("Outlet") = {21};
Physical Surface("Walls") = {17, 25, 26};Visually the model will look like this:
Lastly, the mand.din file.
> See the DINGuide (on the Downloads page) for reference.
mand.din
title Test Gmsh man model
steps 200 1.e-5
opendx off
#use gmsh fluid
use vtk
save cpu 1 h
output every 25
density,1.0
vislam 18.6e-6
pref, coor, 1.5, 1.7, 1
relax 0.4 0.1 0.4 0.8
#turbulence ke 0.001
#thermal on
init,field,0.0 0.0 -0.1,,1.e-4,1e-4
scheme UVW GAMMA
slope UVW vnf
slope P vnf
slope KEPS vnf
post P vert
post UVW vert
boundary,man
wall
noslip
0.0 0.0 0.0
fixed
273 + 38 0.0
boundary,inlet
inlet
0.0 0.0 -1.0
1.0
293
inle
0.25 0.01
boundary,outlet
outlet
1.0
boundary,floor
symp
boundary,walls
sympThis time, we have added an interesting command on line 12 (highlighted above), which sets the corner of the mesh as a reference for the pressure calculated in the rest.
Moreover, the post commands on line 25 and 26, will be explained later as well.