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-   -   Gmsh - cavity tutorial (http://www.cfd-online.com/Forums/openfoam-meshing-open/67790-gmsh-cavity-tutorial.html)

s&m August 26, 2009 14:08

Gmsh - cavity tutorial
 
Hi to everyone,
i have installed OP1-6, and i've compiled the tutorial file "cavity" with rhoPisoFoam, and obliously, it worked until time 10.0.

than i created a mesh with Gmsh, (this is the .geo) file:

Point(1) = {1, 1, 0, 0.1};
Point(2) = {1, -1, 0, 0.1};
Point(3) = {-1, -1, 0, 0.1};
Point(4) = {-1, 1, 0, 0.1};
Point(5) = {1, -1, 0.1, 0.1};
Point(6) = {1, 1, 0.1, 0.1};
Point(10) = {-1, 1, 0.1, 0.1};
Point(14) = {-1, -1, 0.1, 0.1};
Line(1) = {1, 4};
Line(2) = {4, 3};
Line(3) = {3, 2};
Line(4) = {2, 1};
Line(8) = {5, 6};
Line(9) = {6, 10};
Line(10) = {10, 14};
Line(11) = {14, 5};
Line(13) = {2, 5};
Line(14) = {1, 6};
Line(18) = {4, 10};
Line(22) = {3, 14};
Line Loop(6) = {4, 1, 2, 3};
Plane Surface(6) = {6};
Line Loop(15) = {4, 14, -8, -13};
Ruled Surface(15) = {15};
Line Loop(19) = {1, 18, -9, -14};
Ruled Surface(19) = {19};
Line Loop(23) = {2, 22, -10, -18};
Ruled Surface(23) = {23};
Line Loop(27) = {3, 13, -11, -22};
Ruled Surface(27) = {27};
Line Loop(28) = {8, 9, 10, 11};
Plane Surface(28) = {28};
Surface Loop(1) = {6, 28, 15, 19, 23, 27};
Volume(1) = {1};
Physical Surface("movingWall") = {19};
Physical Surface("frontAndBack") = {6, 28};
Physical Surface("fixedWalls") = {15, 23, 27};
Physical Volume(29) = {1};

................................
i made the mesh, and i tried to compile it with the same solver and the same boundary condictions.
however the solver stopped, at time 3.58.


Courant Number mean: 198.24 max: 1.67227e+06
Time = 3.58


diagonal: Solving for rho, Initial residual = 0, Final residual = 0, No Iterations 0
DILUPBiCG: Solving for Ux, Initial residual = 0.998601, Final residual = 2.41959, No Iterations 1001
DILUPBiCG: Solving for Uy, Initial residual = 0.998444, Final residual = 14.9385, No Iterations 1001
DILUPBiCG: Solving for Uz, Initial residual = 0.998493, Final residual = 2.08993, No Iterations 1001
DILUPBiCG: Solving for h, Initial residual = 0.996783, Final residual = 0.626569, No Iterations 1001


Maximum number of iterations exceeded#0 Foam::error::printStack(Foam::Ostream&) in "/home/s-m/OpenFOAM/OpenFOAM-1.6/lib/linuxGccDPOpt/libOpenFOAM.so"
#1 Foam::error::abort() in "/home/s-m/OpenFOAM/OpenFOAM-1.6/lib/linuxGccDPOpt/libOpenFOAM.so"
#2 Foam::hPsiThermo<Foam::pureMixture<Foam::constTran sport<Foam::specieThermo<Foam::hConstThermo<Foam:: perfectGas> > > > >::calculate() in "/home/s-m/OpenFOAM/OpenFOAM-1.6/lib/linuxGccDPOpt/libbasicThermophysicalModels.so"
#3 Foam::hPsiThermo<Foam::pureMixture<Foam::constTran sport<Foam::specieThermo<Foam::hConstThermo<Foam:: perfectGas> > > > >::correct() in "/home/s-m/OpenFOAM/OpenFOAM-1.6/lib/linuxGccDPOpt/libbasicThermophysicalModels.so"
#4 main in "/home/s-m/OpenFOAM/OpenFOAM-1.6/applications/bin/linuxGccDPOpt/rhoPisoFoam"
#5 __libc_start_main in "/lib/tls/i686/cmov/libc.so.6"
#6 _start at /usr/src/packages/BUILD/glibc-2.9/csu/../sysdeps/i386/elf/start.S:122


From function specieThermo<thermo>::T(scalar f, scalar T0, scalar (specieThermo<thermo>::*F)(const scalar) const, scalar (specieThermo<thermo>::*dFdT)(const scalar) const) const
in file /home/dm2/henry/OpenFOAM/OpenFOAM-1.6/src/thermophysicalModels/specie/lnInclude/specieThermoI.H at line 68.

I noticed that:
  • the courant numer is high, but in the tutorial is allways small.
  • the evolution of the fluid is different between my file and the first (i saw it with paraview).
So i think that the problem is the only the mesh, because it's the only difference, but what i have to do for adjust it?

thank you to everyone!

ericnutsch January 6, 2010 19:58

I have had good luck with the quality of meshes scripted in gmsh.

It is likely that the boundary conditions are slightly mixed up. Thats where the majority of my problems have derived.

Scan through all(even ones that dont seem important) of the case files checking to make sure the correct boundaries are referenced.


Good Luck!

lindsaywestraadt January 22, 2010 06:12

why does this not work for me?
 
Hi guys

I have the same problem (albeit a year later), so I tried newbee's advice. But there's something wrong with mine. It extrudes the surface to create a 'box', but it doesn't create volume elements. It just creates two surfaces with the same 2D mesh.

Can anyone help?

Lindsay :confused:

lindsaywestraadt January 22, 2010 06:13

Umm ... wrong thread
 
:D ..........


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