CFD Online Logo CFD Online URL
www.cfd-online.com
[Sponsors]
Home > Forums > OpenFOAM Running, Solving & CFD

problem?

Register Blogs Members List Search Today's Posts Mark Forums Read

Reply
 
LinkBack Thread Tools Display Modes
Old   May 17, 2013, 05:19
Unhappy problem?
  #1
New Member
 
chaoqing min
Join Date: Mar 2013
Posts: 10
Rep Power: 4
nennbs is on a distinguished road
Hi, everyone.

Now I meet with the problem as follows,

Time = 0.05

smoothSolver: Solving for Ux, Initial residual = 1, Final residual = 0.0610913, No Iterations 2
smoothSolver: Solving for Uy, Initial residual = 1, Final residual = 0.0543365, No Iterations 4
smoothSolver: Solving for Uz, Initial residual = 1, Final residual = 0.0650467, No Iterations 2
GAMG: Solving for p, Initial residual = 1, Final residual = 8.29534e-09, No Iterations 305
time step continuity errors : sum local = 6.87035e-11, global = -3.69711e-13, cumulative = -3.69711e-13
smoothSolver: Solving for epsilon, Initial residual = 0.168528, Final residual = 0.00822444, No Iterations 2
bounding epsilon, min: -1.30591 max: 22.8225 average: 1.34645
smoothSolver: Solving for k, Initial residual = 1, Final residual = 0.0306537, No Iterations 3
bounding k, min: -29.4278 max: 338.848 average: 1.46748
ExecutionTime = 2.98 s ClockTime = 3 s

Time = 0.1

smoothSolver: Solving for Ux, Initial residual = 0.713072, Final residual = 0.0438459, No Iterations 4
smoothSolver: Solving for Uy, Initial residual = 0.215975, Final residual = 0.0171105, No Iterations 2
smoothSolver: Solving for Uz, Initial residual = 0.594642, Final residual = 0.0478476, No Iterations 3
GAMG: Solving for p, Initial residual = 0.597969, Final residual = 9.74486e-09, No Iterations 488
time step continuity errors : sum local = 2.2033e-10, global = -1.97881e-11, cumulative = -2.01578e-11
smoothSolver: Solving for epsilon, Initial residual = 0.0527079, Final residual = 0.00391902, No Iterations 2
bounding epsilon, min: -12.046 max: 2622.6 average: 2.50039
#0 Foam::error:rintStack(Foam::Ostream&) in "/home/ifas/OpenFOAM/OpenFOAM-2.1.1/platforms/linux64GccDPOpt/lib/libOpenFOAM.so"
#1 Foam::sigFpe::sigHandler(int) in "/home/ifas/OpenFOAM/OpenFOAM-2.1.1/platforms/linux64GccDPOpt/lib/libOpenFOAM.so"
#2 in "/lib64/libc.so.6"
#3 Foam::divide(Foam::Field<double>&, Foam::UList<double> const&, Foam::UList<double> const&) in "/home/ifas/OpenFOAM/OpenFOAM-2.1.1/platforms/linux64GccDPOpt/lib/libOpenFOAM.so"
#4 void Foam::divide<Foam::fvPatchField>(Foam::FieldField< Foam::fvPatchField, double>&, Foam::FieldField<Foam::fvPatchField, double> const&, Foam::FieldField<Foam::fvPatchField, double> const&) in "/home/ifas/OpenFOAM/OpenFOAM-2.1.1/platforms/linux64GccDPOpt/lib/libincompressibleRASModels.so"
#5 Foam::tmp<Foam::GeometricField<double, Foam::fvPatchField, Foam::volMesh> > Foam:perator/<Foam::fvPatchField, Foam::volMesh>(Foam::GeometricField<double, Foam::fvPatchField, Foam::volMesh> const&, Foam::GeometricField<double, Foam::fvPatchField, Foam::volMesh> const&) in "/home/ifas/OpenFOAM/OpenFOAM-2.1.1/platforms/linux64GccDPOpt/lib/libincompressibleRASModels.so"
#6 Foam::incompressible::RASModels::realizableKE::cor rect() in "/home/ifas/OpenFOAM/OpenFOAM-2.1.1/platforms/linux64GccDPOpt/lib/libincompressibleRASModels.so"
#7
in "/home/ifas/OpenFOAM/OpenFOAM-2.1.1/platforms/linux64GccDPOpt/bin/simpleFoam"
#8 __libc_start_main in "/lib64/libc.so.6"
#9
at /home/abuild/rpmbuild/BUILD/glibc-2.15/csu/../sysdeps/x86_64/elf/start.S:116
Gleitkomma-Ausnahme


Can zou help me?

Thanks millions in advance.
nennbs is offline   Reply With Quote

Old   May 17, 2013, 06:01
Default
  #2
ngj
Senior Member
 
Niels Gjoel Jacobsen
Join Date: Mar 2009
Location: Deltares, Delft, The Netherlands
Posts: 1,605
Rep Power: 25
ngj will become famous soon enoughngj will become famous soon enough
Hi,

Your values of k and epsilon become negative. This means that there is a possibility of dividing by zero!

Try start upwinding the divergence terms for k and epsilon and see, if this helps in bounding the values of k and epsilon. Another problem could be your boundary conditions for k and epsilon. I have never worked with this type of turbulence model, but it seems that one has to be careful in order to get a stable solution.

All the best,

Niels
ngj is offline   Reply With Quote

Reply

Tags
17th, may 2013

Thread Tools
Display Modes

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Trackbacks are On
Pingbacks are On
Refbacks are On


Similar Threads
Thread Thread Starter Forum Replies Last Post
UDF compiling problem Wouter Fluent UDF and Scheme Programming 6 June 6, 2012 04:43
Gambit - meshing over airfoil wrapping (?) problem JFDC FLUENT 1 July 11, 2011 05:59
natural convection problem for a CHT problem Se-Hee CFX 2 June 10, 2007 06:29
Adiabatic and Rotating wall (Convection problem) ParodDav CFX 5 April 29, 2007 19:13
Is this problem well posed? Thomas P. Abraham Main CFD Forum 5 September 8, 1999 14:52


All times are GMT -4. The time now is 11:02.