[mabinty]

dear all!

i modified chtMultiRegionFoam including a radiation model in the fluid region. the radiation model, or better the BC of the radiation model, calculates a radiative wall heat flux Qr at every boundary and writes it out at the specified time steps.

now i need to access Qr from the solid region, i.e. in the forAll(solidRegions, i)-loop (see solvers/heatTransfer/chtMultiRegionFoam/chtMultiRegionFoam.C line 104) .

first i tried to create a IOobject QrFluid in creatFluidFields with the MUST_READ option. but as it isn t updated in the code (and for now I don t know how to do it) it doesn t read the actual Qr field.

i also tried to use the db().lookupobject<> function which returns a reference to the object registry like:

    const volScalarField& QrFluid = UFluid[j].db().lookupObject<volScalarField>("Qr");

but without success. the code compiles but throws the error message below when executed:

--> FOAM FATAL ERROR: 
hanging pointer, cannot dereference

    From function PtrList::operator[] const
    in file /opt/openfoam171/src/OpenFOAM/lnInclude/PtrListI.H at line 108.

FOAM aborting

#0  Foam::error::printStack(Foam::Ostream&) in "/opt/openfoam171/lib/linux64GccDPOpt/libOpenFOAM.so"
#1  Foam::error::abort() in "/opt/openfoam171/lib/linux64GccDPOpt/libOpenFOAM.so"
#2  
 in "/home/aa/OpenFOAM/aa-1.7.1/applications/bin/linux64GccDPOpt/yazdRadBC"
#3  
 in "/home/aa/OpenFOAM/aa-1.7.1/applications/bin/linux64GccDPOpt/yazdRadBC"
#4  __libc_start_main in "/lib/libc.so.6"
#5  
 in "/home/aa/OpenFOAM/aa-1.7.1/applications/bin/linux64GccDPOpt/yazdRadBC"
Aborted

does anybody have an idea how to access the fluid field Qr from the solid region?

i greatly appreciate your comments!
thx in advance!!
aram

[mirko]

Originally Posted by mabinty

dear all!

i modified chtMultiRegionFoam including a radiation model in the fluid region. the radiation model, or better the BC of the radiation model, calculates a radiative wall heat flux Qr at every boundary and writes it out at the specified time steps.

now i need to access Qr from the solid region, i.e. in the forAll(solidRegions, i)-loop (see solvers/heatTransfer/chtMultiRegionFoam/chtMultiRegionFoam.C line 104) .

first i tried to create a IOobject QrFluid in creatFluidFields with the MUST_READ option. but as it isn t updated in the code (and for now I don t know how to do it) it doesn t read the actual Qr field.

i also tried to use the db().lookupobject<> function which returns a reference to the object registry like:

    const volScalarField& QrFluid = UFluid[j].db().lookupObject<volScalarField>("Qr");

but without success. the code compiles but throws the error message below when executed:

--> FOAM FATAL ERROR: 
hanging pointer, cannot dereference

    From function PtrList::operator[] const
    in file /opt/openfoam171/src/OpenFOAM/lnInclude/PtrListI.H at line 108.

FOAM aborting

#0  Foam::error::printStack(Foam::Ostream&) in "/opt/openfoam171/lib/linux64GccDPOpt/libOpenFOAM.so"
#1  Foam::error::abort() in "/opt/openfoam171/lib/linux64GccDPOpt/libOpenFOAM.so"
#2  
 in "/home/aa/OpenFOAM/aa-1.7.1/applications/bin/linux64GccDPOpt/yazdRadBC"
#3  
 in "/home/aa/OpenFOAM/aa-1.7.1/applications/bin/linux64GccDPOpt/yazdRadBC"
#4  __libc_start_main in "/lib/libc.so.6"
#5  
 in "/home/aa/OpenFOAM/aa-1.7.1/applications/bin/linux64GccDPOpt/yazdRadBC"
Aborted

does anybody have an idea how to access the fluid field Qr from the solid region?

i greatly appreciate your comments!
thx in advance!!
aram

Funny, I am also hacking on the same solver, and had the same error yesterday. In my case, I traced the error with print statements to

        radiation.set
        (
            i,
            radiation::radiationModel::New(thermoFluid[i].T())
        );

in createFluidFields.H. It turned out that thermoFluid was not initialized. I had to prepend

        thermoFluid.set
        (
            i,
            basicRhoThermo::New(fluidRegions[i]).ptr()
        );

So, my guess is that you don't have a variable declared/initialized.

Good luck,

Mirko

[mabinty]

hey Mirko!

thanks a lot for your reply!!

the chtMRF code where i added a radiation and combustion model actually works. i found some troubles (= numerical instability) when taking the radiative heat flux Qr for the cht-BC into account. hence, i want to try a new approach where Qr is applied as source term in the solid.

the problem i described above happens cause i havn t understood yet how to dereference the fluid field pointer lists outside of the fluid-loop. the error message comes from:

/opt/openfoam171/src/OpenFOAM/lnInclude/PtrListI.H at line 108

in the operator[] because there seems to be no element in SOMTHING[i]:

if (!ptrs_[i])
    {
        FatalErrorIn("PtrList::operator[]")
            << "hanging pointer, cannot dereference"
            << abort(FatalError);
    }

the operator<< which writes to OStream works, hence

Info<< "QrFluid: " << UFluid[j].db().lookupObject<volScalarField>("Qr") 
    << endl;

shows me the Qr-volField i want.

any idea? i ll keep on digging and report!!

cheers,
aram

[mirko]

Aram,

OF2.0 chtMultiRegionFoam includes radiation.

As for debugging, my approach is to copy the relevant solver or BC to my user directories, compile them, and then start adding print/Info statements to narrow down the cause of the error.

Mirko