[gian_ing]

I tried another simulation using simplefoam with a new mesh and NO high aspect ratio cells.
The same error results.
I paste it here.
I don't know why all the residuals diverge.


DILUPBiCG: Solving for Ux, Initial residual = 0.999988, Final residual = 8.45492e-09, No Iterations 78
DILUPBiCG: Solving for Uy, Initial residual = 0.99999, Final residual = 6.45854e-09, No Iterations 77
DICPCG: Solving for p, Initial residual = 0.0766972, Final residual = 4.87576e-09, No Iterations 408
DICPCG: Solving for p, Initial residual = 0.377693, Final residual = 9.83582e-09, No Iterations 5
time step continuity errors : sum local = 3.3791e+21, global = -1.23254e+21, cumulative = -1.23254e+21
ExecutionTime = 2.33 s ClockTime = 3 s

Time = 0.9

DILUPBiCG: Solving for Ux, Initial residual = 0.999953, Final residual = 6.14167e-09, No Iterations 1
DILUPBiCG: Solving for Uy, Initial residual = 0.999839, Final residual = 1.51288e-09, No Iterations 1
#0 Foam::error::printStack(Foam:stream&) in "/home/cfduser/OpenFOAM/OpenFOAM-1.5/lib/linux64GccDPOpt/libOpenFOAM.so"
#1 Foam::sigFpe::sigFpeHandler(int) in "/home/cfduser/OpenFOAM/OpenFOAM-1.5/lib/linux64GccDPOpt/libOpenFOAM.so"
#2 ?? in "/lib/libc.so.6"
#3 Foam::DICPreconditioner::calcReciprocalD(Foam::Fie ld<double>&, Foam::lduMatrix const&) in "/home/cfduser/OpenFOAM/OpenFOAM-1.5/lib/linux64GccDPOpt/libOpenFOAM.so"
#4 Foam::DICPreconditioner::DICPreconditioner(Foam::l duMatrix::solver const&, Foam::Istream&) in "/home/cfduser/OpenFOAM/OpenFOAM-1.5/lib/linux64GccDPOpt/libOpenFOAM.so"
#5 Foam::lduMatrix::preconditioner::addsymMatrixConst ructorToTable<foam::dicprecond itioner>::New(Foam::lduMatrix::solver const&, Foam::Istream&) in "/home/cfduser/OpenFOAM/OpenFOAM-1.5/lib/linux64GccDPOpt/libOpenFOAM.so"
#6 Foam::lduMatrix::preconditioner::New(Foam::lduMatr ix::solver const&, Foam::Istream&) in "/home/cfduser/OpenFOAM/OpenFOAM-1.5/lib/linux64GccDPOpt/libOpenFOAM.so"
#7 Foam::PCG::solve(Foam::Field<double>&, Foam::Field<double> const&, unsigned char) const in "/home/cfduser/OpenFOAM/OpenFOAM-1.5/lib/linux64GccDPOpt/libOpenFOAM.so"
#8 Foam::fvMatrix<double>::solve(Foam::Istream&) in "/home/cfduser/OpenFOAM/OpenFOAM-1.5/lib/linux64GccDPOpt/libfiniteVolume.so"
#9 main in "/home/cfduser/OpenFOAM/OpenFOAM-1.5/applications/bin/linux64GccDPOpt/simpleFoam "
#10 __libc_start_main in "/lib/libc.so.6"
#11 Foam::regIOobject::readIfModified() in "/home/cfduser/OpenFOAM/OpenFOAM-1.5/applications/bin/linux64GccDPOpt/simpleFoam "
Floating point exception

[santos]

Just a wild guess: are 'up' and 'down' patches supposed to have Ux=1, or are they supposed to be symmetry planes?

Regards,
Jose Santos

[antonio_ing]

I guess these are the BC at infinity (something like the inlet)

[gian_ing]

Antonio's guess was right.
They're not simmetry planes, they're something like a Ux at infinity.

Regards

[naish]

Hi Gianluca
I have te same problems, please can you explain how do you fixed your problem.
I do not understand " no symmetry planes / Ux at infinity"

Regards

[gian_ing]

Initially I set a simmetry plane like cylinder but that was not a solution.
For my case the problem was not in the boundary conditions but I was mistaken setting a "laminar" condition in RASproperties file with a high Reynolds number simulation.
That made the code go crazy.
The other settings should be ok.

If you need some more clarification let me know but I'm not an expert.

Good luck
Regards