[joshwilliams]

Hello,


We are using cloud computing to investigate the effects of two-way and four-way coupling with high masses of small particles (between 1 and 10 micron). I have ran a case with 100 million particles (diameter, dp = 10 micron). When increasing to 300 million, the simulation cannot initialise and I get a floating point error as shown below. Has anyone encountered this before? I am using patchInjection model with MPPICFoam solver.


I assume it is linked to this post on precision issue when creating very large meshes (something we also want to do).

Constructing kinematicCloud kinematicCloud
Constructing particle forces
    Selecting particle force WenYuDrag
    Selecting particle force gravity
Constructing cloud functions
    Selecting cloud function outletExiting of type patchPostProcessing
Constructing particle injection models
Creating injector: model1
Selecting injection model patchInjection
    Constructing 3-D injection
    Choosing nParticle to be a fixed value, massTotal variable now does not determine anything.
#0  Foam::error::printStack(Foam::Ostream&) at ??:?
#1  Foam::sigFpe::sigHandler(int) at ??:?
#2  ? in "/lib64/libc.so.6"
#3  Foam::PatchInjection<Foam::KinematicCloud<Foam::Cloud<Foam::MPPICParcel<Foam::KinematicParcel<Foam::particle> > > > >::PatchInjection(Foam::dictionary const&, Foam::KinematicCloud<Foam::Cloud<Foam::MPPICParcel<Foam::KinematicParcel<Foam::particle> > > >&, Foam::word const&) at ??:?
#4  Foam::InjectionModel<Foam::KinematicCloud<Foam::Cloud<Foam::MPPICParcel<Foam::KinematicParcel<Foam::particle> > > > >::adddictionaryConstructorToTable<Foam::PatchInjection<Foam::KinematicCloud<Foam::Cloud<Foam::MPPICParcel<Foam::KinematicParcel<Foam::particle> > > > > >::New(Foam::dictionary const&, Foam::KinematicCloud<Foam::Cloud<Foam::MPPICParcel<Foam::KinematicParcel<Foam::particle> > > >&, Foam::word const&) at ??:?
#5  ? at ??:?
#6  ? at ??:?
#7  ? at ??:?
#8  ? at ??:?
#9  ? at ??:?
#10  __libc_start_main in "/lib64/libc.so.6"
#11  ? at ??:?
Floating point exception (core dumped)

InjectionModel

    injectionModels
    {
        model1
        {
            type            patchInjection;
            parcelBasisType fixed;
            patchName       inlet;
            nParticle       1;
            parcelsPerSecond 30.0e8;
            SOI             0;
            massTotal       0.0;
            U0              (0 0 0);
            duration        0.1;
            flowRateProfile constant 1;
            sizeDistribution
            {
                type        fixedValue;
                fixedValueDistribution
                {
                    value  10.0e-6;
                }
            }
        }
    }

[joshwilliams]

FYI, we managed to fix this by setting "export WM_ARCH_OPTION=64" in etc/bashrc and etc/cshrc, and compiling from scratch.