Meshing
Start Gmsh and create the mesh with:
gmsh -3 t6.geoPossible output
Start Gmsh and create the mesh with:
gmsh -3 t6.geo
Info : Running 'gmsh -3 t6.geo' [Gmsh 4.0.4, 1 node, max. 1 thread]
Info : Started on Tue Nov 13 15:36:08 2018
Info : Reading 't6.geo'...
Info : Reading 't1.geo'...
Info : Done reading 't1.geo'
Info : Done reading 't6.geo'
Info : Meshing 1D...
Info : Meshing curve 1 (Line)
. . .
Info : Meshing curve 32 (extruded)
Info : Done meshing 1D (0 s)
Info : Meshing 2D...
Info : Meshing surface 1 (transfinite)
. . .
Info : Meshing surface 38 (extruded)
Info : Done meshing 2D (0 s)
Info : Meshing 3D...
Info : Meshing volume 1 (extruded)
Info : Done meshing 3D (0 s)
Info : Optimizing 3D mesh...
Info : Done optimizing 3D mesh (0 s)
Info : 1200 vertices 1959 elements
Info : Writing 't6.msh'...
Info : Done writing 't6.msh'
Info : Stopped on Tue Nov 13 15:36:09 2018
Opening t6.msh will show something similar to:
As can be seen, the mesh consists of quadrangles, and is finer near the extremities of line 2 (top one in this view).
Copying mesh
Again, to make sure the mesh file will not be overwritten by the results, we copy and rename the files:
cp t6.msh t6d.mshConverting to dolfyn input
We now convert the mesh into *.cel, a *.vrt, a *.bnd, and optionally an *.inp file using gmsh2dolfyn, and selecting the correct file to convert, in our case: t6d.
gmsh2dolfyn t6dPossible output
Start gmsh2dolfyn converter with:
gmsh2dolfyn t6d
Gmsh2Dolfyn: Converts a Gmsh mesh file to Dolfyn format.
Input must be in Gmsh version 2.0, 2.1, 2.2 or 4 ascii format.
Opening the Gmsh file
File t6d.msh opened
Reading MeshFormat
MeshFormat: 4 0 8
Reading PhysicalNames
Name 2 -> Top
Name 3 -> Left
Name 4 -> Right
Name 5 -> Bottom
Name 6 -> Front
Name 7 -> Back
Name 1 -> Fluid
Entities
Entity 1 surface 7 Back
. . .
Entity 1 volume 1 Fluid
Physical entities found 9
Reading Nodes
Number of entity blocks: 33 Nodes: 1200
Creating the dolfyn .vrt file
File t6d.vrt opened
Point 1 Node 1
. . .
Surface 38 Nodes 504
Nodes written 1200
Gmsh 4: Total Gmsh Entity Blocks to be read in: 9
Gmsh 4: Total Gmsh elements to be read in: 1749
Creating the dolfyn .cel and .bnd files 14 23
File t6d.cel opened
File t6d.bnd opened
Element 1 Back Type 3 551
. . .
Element 1 Fluid Type 5 551
Quad boundaries: 1198
Hexahedral cells: 551
Writing the .inp file
File t6d.inp opened
inp: 2 Top T
inp: 3 Left T
inp: 4 Right T
inp: 5 Bottom T
inp: 6 Front T
inp: 7 Back T
Done gmsh2dolfyn 2018
Running Pre-Processor
Now we will run the pre-processor.
dolgeo -s 1.0 -b t6dIf no options are given with the dolgeo command, you will be prompted for them. Fill in case name t6d, scaling factor of 1.0 (default) and bin as format of geometry file.
Possible output
The pre-processor is run with:
dolgeo -s 1.0 -b t6d
Dolfyn PreProcessor
t6d T T T F
Using command line arguments
Using t6d as input
Opening vertex file
Initialise vertex list
. . .
Region ID: 2 => Top
Region ID: 3 => Left
Region ID: 4 => Right
Region ID: 5 => Bottom
Region ID: 6 => Front
Region ID: 7 => Back
Type 1 regions found: 6 7
WARNING: check inp-file
Using: 1.00000000 binary
Dump binary geometry file
Done
Running Simulation
Finaly we will run the dolfyn simulations.
dolfyn t6dIf no case name is inputted directly, you will be prompted. If so, enter case name t6d.
Possible output
The pre-processor is run with:
dolfyn t6d
This is dolfyn version 0.607
Copyright(C) 2002-2016 Cyclone Fluid Dynamics BV
NL-5583 XM, Waalre, The Netherlands
see http://www.cyclone.nl and https://www.dolfyn.net
Using Sparsekit2 by Yousef Saad
(C) 2005, the Regents of the University of Minnesota
Modules with patches (C) 2004-2010 by B. Tuinstra
see http://www.home.zonnet.nl/bouke_1/dolfyn
Tecplot interface (tecplt.f90) (C) 2006-2012 by
S.B. Kuang, UNSW, Sydney, Australia
VTK interface updated (C) 2007 by J. Jacobs
Static boundary conditions (C) 2011 by J. JoJo
MKL contributions and suggestions by Runar
Using case: t6d
Calling dolfyn t6d .dge
t6d.dge binary
. . .
*** CONVERGENCE *** 8.98416969E-04
Opening restart file
File t6d.rst
Restartfile 400 written
Writing Full Gmsh file...
Done
Maximum change in PP: 2.36398118E-04 8.98416969E-04 1.00000005E-03
Arrays cleaned up
Done t6d
Bye!
That’s it! Now all the calculations have been carried out, we can start to analyze the output.