[yash.aesi]

greetings oll ,

i am trying to solve my case using reactingFoam from last many days . after initial errors nw its running fine but i am still bother about what temperature BC's i need to give inorder to have combustion at fuel inlet , air inlet and internal domain and outlet .

it will be great help if someone will suggest about it .
i had given the following BC's for temp . :

FoamFile
{
    version     2.0;
    format      ascii;
    class       volScalarField;
    location    "0";
    object      T;
}
// * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * //

dimensions      [0 0 0 1 0 0 0];

internalField   uniform 290;

boundaryField
{
    fuel_inlet  
    {
        type            fixedValue;
        value           uniform 600;
    }
    coflow_inlet 
    {
        type            fixedValue;
        value           uniform 800;
    }
    Upper_wall       
    {
        type          zeroGradient;
    }
    Axis
    {
        type            symmetryPlane;
    }
    Outlet
    {
        type            inletOutlet;
        inletValue      uniform 290;
        value           uniform 290;

    }
    frontAndBack
    {
        type            empty;
    }
}

thanks
Regards ,
sonu

[Jhoanse87]

Originally Posted by yash.aesi

greeting oll ,

Above error is solved its just bcz of the wrong BC's , nw my case is running
but there is no combustion ( combustion is on ) . The BC's for temp for fuel inlet is 300 k and air inlet is 500 k . but in this case there combustion is not happening why ?

also if i try to change the BC's to some higher temperature like 600 k then following error is coming :

PHP Code:

diagonal:  Solving for rho, Initial residual = 0, Final residual = 0, No Iterations 0
--> FOAM Warning : 
    From function janafThermo<EquationOfState>::limit(const scalar T) const
    in file /home/opencfd/OpenFOAM/OpenFOAM-2.2.0/src/thermophysicalModels/specie/lnInclude/janafThermoI.H at line 108
    attempt to use janafThermo<EquationOfState> out of temperature range 200 -> 5000;  T = 5006.76 


so can anyone guide me where i am doing wrong ??

Thanks ,
Regard
sonu .

Hi sonu,

I've been having the same problem with reactingFoam without reactions (combustion off). ¿Could you give me the bounday conditions that you used?


Thank you

[yash.aesi]

Helo Jhoan ,
I used the reactingFoam solver for simulating the Diffusion flame. Initially i tried this case without combustion but finally i switched it on . I got results for the combustion On case except few problems like The mass fraction of the products is not coming as it should be ...

I will send you BC's but rite now i m out of station ....


Regards ,
Sonu .

[yash.aesi]

Greeting All,
is it possible to replace the single reaction in reactingFoam solver with the GRI mechanism?? if so then where to give this GRI mechanism as species file is there in constant folder.

Thanks
Regards ,
sonu

[epi_c]

Hi @yash.aesi

Sorry to trouble you. I have a problem while using multiComponentMixture. I want to simulate a multi-component mixture flow without reaction in OpenFOAM-2.3.0. For some purpose, I chose the solver sprayFoam as my reference solver. In createFields.H, I use code

    Info << "Reading thermophysical properties\n" << endl;

    autoPtr<psiReactionThermo> prThermo
    (
        psiReactionThermo::New(mesh)
    );

to set thermal properties. And my thermophysicalProperties dictionary is

thermoType
{
    energy          sensibleEnthalpy;
    specie          specie;
    equationOfState perfectGas;
    thermo          hConst;
    transport       const;
    mixture         multiComponentMixture;
    type            hePsiThermo;
}

species
(
    air
    diesel
);

air
{
    specie
    {
        nMoles      1;
        molWeight   28.9;
    }
    thermodynamics
    {
        Cp          1007;
        Hf          0;
    }
    transport
    {
        mu          1.84e-05;
        Pr          0.7;
    }
}

diesel
{
    specie
    {
        nMoles      1;
        molWeight   142;
    }
    thermodynamics
    {
        Cp          2100;
        Hf          0;
    }
    transport
    {
        mu          7e-6;
        Pr          0.83;
    }
}

But this came an error:

#0  Foam::error::printStack(Foam::Ostream&) in "/home/epi/OpenFOAM/OpenFOAM-2.3.0/platforms/linuxGccDPOpt/lib/libOpenFOAM.so"
#1  Foam::sigFpe::sigHandler(int) in "/home/epi/OpenFOAM/OpenFOAM-2.3.0/platforms/linuxGccDPOpt/lib/libOpenFOAM.so"
#2  Uninterpreted: 
#3  Foam::hePsiThermo<Foam::psiReactionThermo, Foam::SpecieMixture<Foam::multiComponentMixture<Foam::constTransport<Foam::species::thermo<Foam::hConstThermo<Foam::perfectGas<Foam::specie> >, Foam::sensibleEnthalpy> > > > >::calculate() in "/home/epi/OpenFOAM/OpenFOAM-2.3.0/platforms/linuxGccDPOpt/lib/libreactionThermophysicalModels.so"

Would you give me some help? thx!

[wyldckat]

Greetings Francis,

I got the private message you sent me and I prefer to answer here on the forum, so that anyone else can pitch in with ideas.

Answering a bit backwards:

Originally Posted by epi_c

You are expert in using OpenFOAM, please help me, thanks!

I'm an expert in installing OpenFOAM . Other than that, I only know a bit about several things in OpenFOAM .

Originally Posted by epi_c

I tried to change sprayFoam in OpenFOAM-2.3.0 to a non-reaction one. So I changed the createFields.H file, replaced

    Info<< "Creating combustion model\n" << endl;

    autoPtr<combustionModels::psiCombustionModel> combustion
    (
        combustionModels::psiCombustionModel::New(mesh)
    );

    psiReactionThermo& thermo = combustion->thermo();

with

    Info << "Reading thermophysical properties\n" << endl;

    autoPtr<psiReactionThermo> prThermo
    (
        psiReactionThermo::New(mesh)
    );

This is crucial information that you had omitted in the post above.

I'm having a hard time understanding why you're dropping the psiCombustionModel and to trying use psiReactionThermo directly, when you already have access to it from "combustion->thermo()".

Beyond this, it would be helpful to know what more is shown above the stack trace, i.e. what is above the last output you've shown. And what other modifications did you do to the sprayFoam solver, since clearly it originally uses "combustion" for something

Best regards,
Bruno

[epi_c]

Greetings Bruno,

Er, forget about sprayFoam. What I want to do is to construct a two-component mixture without reaction, then using it to construct a SLGThermo object which is to be passed to basicSprayCloud as an argument. Cause there are just two components and no reaction between them, so I think I can use multiComponentMixture rather than reactingMixture. Then the problem came when construct the mixture. Attached is piece of my code, trouble you again.


Finally the problem was solved by using gdb. It is found that the universal gas constant wasn't initialized cause lack of relevant library.

Foam::perfectGas<Foam::specie>::psi (this=0x8d0e80c, T=273)
    at /home/epi/OpenFOAM/OpenFOAM-2.2.2/src/thermophysicalModels/specie/lnInclude/perfectGasI.H:88
88	    return 1.0/(this->R()*T);
(gdb) s
Foam::specie::R (this=0x8d0e80c)
    at /home/epi/OpenFOAM/OpenFOAM-2.2.2/src/thermophysicalModels/specie/lnInclude/specieI.H:99
99	    return RR/molWeight_;
(gdb) p RR
$1 = 0
(gdb) p molWeight_ 
$2 = 28.899999999999999

But it didn't complain while compiling. After I added the library to Make/options, the problem solved.

[esmail7]

Originally Posted by epi_c

Hi @yash.aesi

Sorry to trouble you. I have a problem while using multiComponentMixture. I want to simulate a multi-component mixture flow without reaction in OpenFOAM-2.3.0. For some purpose, I chose the solver sprayFoam as my reference solver. In createFields.H, I use code

    Info << "Reading thermophysical properties\n" << endl;

    autoPtr<psiReactionThermo> prThermo
    (
        psiReactionThermo::New(mesh)
    );

to set thermal properties. And my thermophysicalProperties dictionary is

thermoType
{
    energy          sensibleEnthalpy;
    specie          specie;
    equationOfState perfectGas;
    thermo          hConst;
    transport       const;
    mixture         multiComponentMixture;
    type            hePsiThermo;
}

species
(
    air
    diesel
);

air
{
    specie
    {
        nMoles      1;
        molWeight   28.9;
    }
    thermodynamics
    {
        Cp          1007;
        Hf          0;
    }
    transport
    {
        mu          1.84e-05;
        Pr          0.7;
    }
}

diesel
{
    specie
    {
        nMoles      1;
        molWeight   142;
    }
    thermodynamics
    {
        Cp          2100;
        Hf          0;
    }
    transport
    {
        mu          7e-6;
        Pr          0.83;
    }
}

But this came an error:

#0  Foam::error::printStack(Foam::Ostream&) in "/home/epi/OpenFOAM/OpenFOAM-2.3.0/platforms/linuxGccDPOpt/lib/libOpenFOAM.so"
#1  Foam::sigFpe::sigHandler(int) in "/home/epi/OpenFOAM/OpenFOAM-2.3.0/platforms/linuxGccDPOpt/lib/libOpenFOAM.so"
#2  Uninterpreted: 
#3  Foam::hePsiThermo<Foam::psiReactionThermo, Foam::SpecieMixture<Foam::multiComponentMixture<Foam::constTransport<Foam::species::thermo<Foam::hConstThermo<Foam::perfectGas<Foam::specie> >, Foam::sensibleEnthalpy> > > > >::calculate() in "/home/epi/OpenFOAM/OpenFOAM-2.3.0/platforms/linuxGccDPOpt/lib/libreactionThermophysicalModels.so"

Would you give me some help? thx!

I think, this error is related to your BCs. change Bc to zero gradient instead of uniform value on walls.

[samchen1993]

Hi sir i'm using reactingFoam in my case to solve for my master project, i'm applying turbulence flow and models into my case does that mean in my combustionproperties i need to change it from laminar<psiChemistryCombustion>; to combustionModel PaSR<psiChemistryCombustion>; .....if so i would like to know how to define cmix or is there any coefficient that can be applied as default?