[Wakatsuki]

Hi, I am using olaflow solver for the simulation of overtopping of vertical seawall, everything looks fine after I setFields, However, when I typed 'olaflow' to run the simulation, this error kept appearing, I have tried many methods, but the progress was very limited.

// * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * //
Create time

Create mesh for time = 0

Selecting dynamicFvMesh staticFvMesh

PIMPLE: No convergence criteria found


PIMPLE: Operating solver in transient mode with 1 outer corrector
PIMPLE: Operating solver in PISO mode


Reading field porosityIndex

Porosity NOT activated

Reading field p_rgh

Reading field U

Reading/calculating face flux field phi

Reading transportProperties

Selecting incompressible transport model Newtonian
Selecting incompressible transport model Newtonian
Selecting turbulence model type laminar
Selecting laminar stress model Stokes

Reading g

Reading hRef
Calculating field g.h

No MRF models present

No finite volume options present
DICPCG: Solving for pcorr, Initial residual = 0, Final residual = 0, No Iterations 0
time step continuity errors : sum local = 0, global = 0, cumulative = 0
Courant Number mean: 0 max: 0

Starting time loop

Courant Number mean: 0 max: 0
Interface Courant Number mean: 0 max: 0
deltaT = 0.00595238
Time = 0.00595238

MULES: Solving for alpha.water
alpha.water BC on patch inlet
Phase-1 volume fraction = 0.278097 Min(alpha.water) = 0 Max(alpha.water) = 1
alpha.water BC on patch inlet
MULES: Solving for alpha.water
alpha.water BC on patch inlet
Phase-1 volume fraction = 0.278097 Min(alpha.water) = 0 Max(alpha.water) = 1
#0 Foam::error printStack(Foam::Ostream&) at ??:?
#1 Foam::sigFpe::sigHandler(int) at ??:?
#2 ? in "/lib/x86_64-linux-gnu/libc.so.6"
#3 Foam DICPreconditioner::calcReciprocalD(Foam::Field<dou ble>&, Foam::lduMatrix const&) at ??:?
#4 Foam DICPreconditioner DICPreconditioner(Foam::lduMatrix::solver const&, Foam::dictionary const&) at ??:?
#5 Foam::lduMatrix preconditioner::addsymMatrixConstructorToTable<Foa m DICPreconditioner>::New(Foam::lduMatrix::solver const&, Foam::dictionary const&) at ??:?
#6 Foam::lduMatrix preconditioner::New(Foam::lduMatrix::solver const&, Foam::dictionary const&) at ??:?
#7 Foam::PCG::solve(Foam::Field<double>&, Foam::Field<double> const&, unsigned char) const at ??:?
#8 Foam::fvMatrix<double>::solveSegregated(Foam::dict ionary const&) at ??:?
#9 Foam::fvMatrix<double>::solve(Foam::dictionary const&) in "/home/boapink/OpenFOAM/boapink-7/platforms/linux64GccDPInt32Opt/bin/olaFlow"
#10 Foam::fvMatrix<double>::solve() in "/home/boapink/OpenFOAM/boapink-7/platforms/linux64GccDPInt32Opt/bin/olaFlow"
#11 ? in "/home/boapink/OpenFOAM/boapink-7/platforms/linux64GccDPInt32Opt/bin/olaFlow"
#12 __libc_start_main in "/lib/x86_64-linux-gnu/libc.so.6"
#13 ? in "/home/boapink/OpenFOAM/boapink-7/platforms/linux64GccDPInt32Opt/bin/olaFlow"
Floating point exception (core dumped)

[Rosy]

Hello Wakatsuki,

when I type 'olaflow' to run the simulation, I have a similar error. How did you solve this?

[Phicau]

Hi Both,
there is a floating point error (sigFpe - division by 0) when solving the pressure Poisson equation. Probably this is due to a bad mesh or choosing incorrect boundary conditions, but there are other possibilities.

If you started your case from an olaFlow tutorial, I would suggest that you revert the changes that you have made, one by one, until you find which one leads to this error.

Best,
Pablo

[Rosy]

Hi Pablo,
thanks for your quick reply.

As you suggested, I started my case from an OlaFlow tutorial, editing the appropriate files. I want to model two vertical rigid cylinders partially submerged in water and subject to wave motion (solitary wave). Wanting to implement the model in 3D, I started from the IRREGTANK tutorial, modifying BlockMeshDict, adding two cylinders drawn in Salome, providing a mesh with SnappyHexMeshDict. Being new to Openfoam, unfortunately I can't understand where the mistake is, because my case doesn't work. Some modified files are attached. I would be really grateful if you agreed to help me.

[Phicau]

Hi Rosy,
As I mentioned it is an issue with the pressure boundary conditions. You cannot simply specify zero gradient, it needs to be fixedFluxPressure, the same as the other walls already defined in the file.

I would suggest that you spend some time learning from the tutorials and trying simple 2D cases before getting into more complex cases.

Best,
Pablo