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Old   June 21, 2012, 06:20
Default Air Conditioned room groovyBC
  #1
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Sebastian
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Dear All,

I have a problem with temperature in my simulation. in first step [0] it's ok 323K but in 1 step [1] it's 300K..
I use buoyantBoussinesqSimpleFoam with groovyBC
My start files

T
Code:
dimensions      [0 0 0 1 0 0 0];

internalField   uniform 300;

boundaryField
{
    
    RAK2
    {
    type groovyBC;
    value uniform 323;
    gradientExpression "gradT";
    fractionExpression "0";
    variables "heatFlux= 0.00005;gradT=heatFlux/kappaEff;";
        
     
    }
    RAK1
    {
        type groovyBC;
        value uniform 323;
        gradientExpression "gradT";
        fractionExpression "0";
        variables "heatFlux= 0.00005;gradT=heatFlux/kappaEff;";
        
       
    }
    FAN1
    {
        type            fixedValue;
        value           uniform 287;
        
       
    }
    FAN2
    {
        type            fixedValue;
     value           uniform 287;
    
    RAK1IN3
    {
    type        fixedValue;
    vale        uniform 323;
    }
    RAK1IN4
    {
    type        fixedValue;
    value        uniform 323;
    }
    
    RAK2IN3
    {
    type        fixedValue;
    value        uniform 323;
    }
    RAK2IN4
    {
    type        fixedValue;
    value        uniform 323;
    }
        
       
    }
    ".*"
    {
        type            zeroGradient;
    }
    
    
}
here a have also problem with variables "heatFlux= 0.00005;gradT=heatFlux/kappaEff;"; where i have define in my case kappaEff? i read that kappaEff is
"kappaEff = turbulence->nu()/Pr + turbulence->nut()/Prt

Prt has no units-> kappaEff = m^2/s"

U
Code:
dimensions      [0 1 -1 0 0 0 0];

internalField   uniform (0 0 0);

boundaryField
{
    WALL
    {
        type            fixedValue;
        value           uniform (0 0 0);
    }
    FLOOR
    {
        type            fixedValue;
        value           uniform (0 0 0);
    }
    BOX1
    {
        type            fixedValue;
        value           uniform (0 0 0);
    }
    BOX2
    {
        type            fixedValue;
        value           uniform (0 0 0);
    }
    RAK2
    {
        type            fixedValue;
        value           uniform (0 0 0);
    }
    RAK1
    {
        type            fixedValue;
        value           uniform (0 0 0);
    }
    FAN1
    {
        type            fixedValue;
        value           uniform (0 0 1);
    }
    FAN2
    {
        type            fixedValue;
        value           uniform (0 0 1);
    }
    RAK1IN1
    {
        type            fixedValue;
        value           uniform (1 0 0);
    }
     RAK1IN2
    {
        type            fixedValue;
        value           uniform (1 0 0);
    }
     RAK1IN3
    {
        type            fixedValue;
        value           uniform (1 0 0);
    }
    RAK1IN4
    {
        type            fixedValue;
        value           uniform (1 0 0);
    }
    RAK2IN1
    {
        type            fixedValue;
        value           uniform (-1 0 0);
    }
     RAK2IN2
    {
        type            fixedValue;
        value           uniform (-1 0 0);
    }
     RAK2IN3
    {
        type            fixedValue;
        value           uniform (-1 0 0);
    }
    RAK2IN4
    {
        type            fixedValue;
        value           uniform (-1 0 0);
    }
    FAN1_WALL
    {
        type            fixedValue;
        value           uniform (0 0 0);
    }
    FAN2_WALL
    {
        type            fixedValue;
        value           uniform (0 0 0);
    }
    CLIM1
    {
        type            pressureInletOutletVelocity;
                value           uniform (0 0 0);
    }
    CLIM2
    {
        type            pressureInletOutletVelocity;
                value           uniform (0 0 0);
    }
    CLIM3
    {
        type            pressureInletOutletVelocity;
                value           uniform (0 0 0);
    }
    CLIM4
    {
        type            pressureInletOutletVelocity;
                value           uniform (0 0 0);
    }
    CLIM5
    {
        type            pressureInletOutletVelocity;
                value           uniform (0 0 0);
    }
    CLIM6
    {
        type            pressureInletOutletVelocity;
                value           uniform (0 0 0);
    }
    CLIM6_WALL
    {
        type            fixedValue;
        value           uniform (0 0 0);
    }
    CLIM5_WALL
    {
        type            fixedValue;
        value           uniform (0 0 0);
    }
    CLIM4_WALL
    {
        type            fixedValue;
        value           uniform (0 0 0);
    }
    CLIM3_WALL
    {
        type            fixedValue;
        value           uniform (0 0 0);
    }
    CLIM2_WALL
    {
        type            fixedValue;
        value           uniform (0 0 0);
    }
    CLIM1_WALL
    {
        type            fixedValue;
        value           uniform (0 0 0);
    }
    ".*"
    {
        type            fixedValue;
        value           uniform (0 0 0);
    }
}
epsilon
Code:
dimensions      [0 2 -3 0 0 0 0];

internalField   uniform 0.01;

boundaryField
{
    
    FAN1
    {
        type            turbulentMixingLengthDissipationRateInlet;
        mixingLength    0.325;
        value           uniform 0.01;
    }
    FAN2
    {
        type            turbulentMixingLengthDissipationRateInlet;
        mixingLength    0.325;
        value           uniform 0.01;
  
    }
    
    RAK1IN1
    {
        type            turbulentMixingLengthDissipationRateInlet;
        mixingLength    0.325;
        value           uniform 0.01;
    }
    RAK1IN2
    {
        type            turbulentMixingLengthDissipationRateInlet;
        mixingLength    0.325;
        value           uniform 0.01;
    }
    RAK1IN3
    {
        type            turbulentMixingLengthDissipationRateInlet;
        mixingLength    0.325;
        value           uniform 0.01;
    }
    RAK1IN4
    {
        type            turbulentMixingLengthDissipationRateInlet;
        mixingLength    0.325;
        value           uniform 0.01;
    }
    RAK2IN1
    {
        type            turbulentMixingLengthDissipationRateInlet;
        mixingLength    0.325;
        value           uniform 0.01;
    }
    RAK2IN2
    {
        type            turbulentMixingLengthDissipationRateInlet;
        mixingLength    0.325;
        value           uniform 0.01;
    }
    RAK2IN3
    {
        type            turbulentMixingLengthDissipationRateInlet;
        mixingLength    0.325;
        value           uniform 0.01;
    }
    RAK2IN4
    {
        type            turbulentMixingLengthDissipationRateInlet;
        mixingLength    0.325;
        value           uniform 0.01;
    }
    
    
    
    CLIM1
    {
       type        inletOutlet;
        inletValue    uniform 0.01;
        /*type            epsilonWallFunction;
                value           uniform 0.01; */

    }
    CLIM2
    {
        type        zeroGradient;
        
            
    }
    CLIM3
    {
       type        zeroGradient;
        
    }
    CLIM4
    {
       type        zeroGradient;
        
    }
    CLIM5
    {
        type        zeroGradient;
           
    }
    CLIM6
    {
       type        zeroGradient;
        
    }
    ".*"
    {
        type            epsilonWallFunction;
        value           uniform 0.01;
    }
    
   
}
k
Code:
dimensions      [0 2 -2 0 0 0 0];

internalField   uniform 0.1;

boundaryField
{
    
    FAN1
    {
    type            fixedValue;
    value        uniform 0.1;
                   
    }
    RAK1IN1
    {
    type            fixedValue;
    value        uniform 0.1;              
    }
    RAK1IN2
    {
    type            fixedValue;
    value        uniform 0.1;              
    }
    RAK1IN3
    {
    type            fixedValue;
    value        uniform 0.1;              
    }
    RAK1IN4
    {
    type            fixedValue;
    value        uniform 0.1;              
    }
    RAK2IN1
    {
    type            fixedValue;
    value        uniform 0.1;              
    }
    RAK2IN2
    {
    type            fixedValue;
    value        uniform 0.1;              
    }
    RAK2IN3
    {
    type            fixedValue;
    value        uniform 0.1;              
    }
    RAK2IN4
    {
    type            fixedValue;
    value        uniform 0.1;              
    }
    
    FAN2
    {
        
     type            fixedValue;
     value        uniform 0.1;
     
    }
    
    CLIM1
    {
       type            zeroGradient;
                       
    }
    CLIM2
    {
        type            zeroGradient;
                        
    }
    CLIM3
    {
        type            zeroGradient;
                        
    }
    CLIM4
    {
       type            zeroGradient;
                       
    }
    CLIM5
    {
        type            zeroGradient;
                       
    }
    CLIM6
    {
       type            zeroGradient;
                      
    }
    ".*"
    {
        type            kqRWallFunction;
        value           uniform 0.1;
    }
    
   
}
kappat
Code:
dimensions      [0 2 -1 0 0 0 0];

internalField   uniform 0;

boundaryField
{
    
    FAN1
    {
        type            calculated;
    }
    FAN2
    {
        type            calculated;
    }
    RAK1IN1
    {
        type            calculated;
    }
     RAK1IN2
    {
        type            calculated;
    }
     RAK1IN3
    {
        type            calculated;
    }
     RAK1IN4
    {
        type            calculated;
    }
     RAK2IN1
    {
        type            calculated;
    }
     RAK2IN2
    {
        type            calculated;
    }
     RAK2IN3
    {
        type            calculated;
    }
     RAK2IN4
    {
        type            calculated;
    }
    CLIM1
    {
        type            zeroGradient;
    }
    CLIM2
    {
        type            zeroGradient;
    }
    CLIM3
    {
        type            zeroGradient;
    }
    CLIM4
    {
        type            zeroGradient;
    }
    CLIM5
    {
        type            zeroGradient;
    }
    CLIM6
    {
        type            zeroGradient;
    }
    ".*"
    {
        type            kappatJayatillekeWallFunction;
        Prt             1.0;
        value           uniform 0;
    }
    
    
}
nut

Code:
dimensions      [0 2 -1 0 0 0 0];

internalField   uniform 0;

boundaryField
{
    
    FAN1
    {
        type            zeroGradient;
    }
    FAN2
    {
        type            zeroGradient;
    }
    RAK1IN1
    {
        type            zeroGradient;
    }
    RAK1IN2
    {
        type            zeroGradient;
    }
    RAK1IN3
    {
        type            zeroGradient;
    }
    RAK1IN4
    {
        type            zeroGradient;
    }
    RAK2IN1
    {
        type            zeroGradient;
    }
    RAK2IN2
    {
        type            zeroGradient;
    }
    RAK2IN3
    {
        type            zeroGradient;
    }
    RAK2IN4
    {
        type            zeroGradient;
    }
    
    CLIM1
    {
        type            zeroGradient;
    }
    CLIM2
    {
        type            zeroGradient;
    }
    CLIM3
    {
        type            zeroGradient;
    }
    CLIM4
    {
       type            zeroGradient;
    }
    CLIM5
    {
        type            zeroGradient;
    }
    CLIM6
    {
        type            zeroGradient;
    }
    ".*"
    {
        type            nutWallFunction;
        value           uniform 0;
    }
   
    
}
p_rgh
Code:
dimensions      [0 2 -2 0 0 0 0];

internalField   uniform 0;

boundaryField
{
    
    FAN1
    {
        type            zeroGradient;
    }
    FAN2
    {
        type            zeroGradient;
    }
    RAK1IN1
    {
        type            zeroGradient;
    }
    RAK1IN2
    {
        type            zeroGradient;
    }
    RAK1IN3
    {
        type            zeroGradient;
    }
    RAK1IN4
    {
        type            zeroGradient;
    }
    RAK2IN1
    {
        type            zeroGradient;
    }
    RAK2IN2
    {
        type            zeroGradient;
    }
    RAK2IN3
    {
        type            zeroGradient;
    }
    RAK2IN4
    {
        type            zeroGradient;
    }
    
    CLIM1
    {
       type            fixedValue;
       value           uniform 0;
       
       
    }
    CLIM2
    {
       type            fixedValue;
       value           uniform 0;
       
       
    }
    CLIM3
    {
        type            fixedValue;
        value           uniform 0;
        
        
       
    }
    CLIM4
    {
       type           fixedValue;
       value           uniform 0;
       
       
    }
    CLIM5
    {
        
        type          fixedValue;
        value           uniform 0;
        
       
    }
    CLIM6
    {
       type            fixedValue;
        value           uniform 0;
       
     
    }
    ".*"
    {
        type            buoyantPressure;
        rho             rhok;
        value           uniform 0;
    }
    
    
}
all problem look like this:





in 0 time step:


and then in 1 time step:



another problem is why in hot outlet "rak1in4" is stil cold air. it was defined as 323K..



any sugestion how i can do good symulation of this problem?

Thanks a lot,
Sebastian
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Old   June 21, 2012, 07:14
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Tian
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Hi Sebastion,

can you share your case?

Bye
Thomas
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Old   June 21, 2012, 07:26
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Sebastian
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Hi Thomas,

of course

https://dl.dropbox.com/u/51938631/ACR-case.rar

Sebastian
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Old   June 21, 2012, 10:14
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Bernhard Gschaider
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Quote:
Originally Posted by Sebaj View Post
Dear All,

I have a problem with temperature in my simulation. in first step [0] it's ok 323K but in 1 step [1] it's 300K..
I use buoyantBoussinesqSimpleFoam with groovyBC
My start files

<snip>

any sugestion how i can do good symulation of this problem?

Thanks a lot,
Sebastian
Personally I don't think that in this case groovyBC is the problem. But to check replace it with a fixedGradient of the values that it calculated.

Just in general: when checking the values in paraview don't use the point interpolated but the cell values as these are the "real" values (the ones that OF calculates with). Point values are interpolated from that and can be misleading. Only use them for the pictures you show afterwards in presentations but not to track problems (as you might be tracking a paraview-problem)

Second question: what are your relaxation parameters?
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Old   June 25, 2012, 03:37
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Sebastian
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Hi,

Relaxation parameters you mean:

g

Code:
dimensions      [0 1 -2 0 0 0 0];

value           ( 0 0 -9.81 );
RASproperties

Code:
RASModel        kEpsilon;
//RASModel        kEpsilonViollet;

turbulence      on;

printCoeffs     on;

k0                  1.0e-10;
epsilon0            1.0e-10;
epsilonSmall        1.0e-10;
transportProperties

Code:
transportModel Newtonian;

// Laminar viscosity
nu              nu [0 2 -1 0 0 0 0] .00037453183520599250; // Re=2670;nu=1/Re

// Thermal expansion coefficient
beta            beta [0 0 0 -1 0 0 0] .00163098878695208970; // Ar=0.016;g=9.81;beta=Ar/g;

// Reference temperature
TRef            TRef [0 0 0 1 0 0 0] 0.75;

// Laminar Prandtl number
Pr              Pr [0 0 0 0 0 0 0] 1.0;

// Turbulent Prandtl number
Prt             Prt [0 0 0 0 0 0 0] 1.0;
controlDict

Code:
application buoyantBoussinesqSimpleFoam;

startFrom       startTime;

startTime       0;

stopAt          endTime;

endTime         100;

deltaT          0.1;

writeControl    timeStep;

writeInterval   10;

purgeWrite      0;

writeFormat     binary;

writePrecision  8;

writeCompression uncompressed;

timeFormat      general;

timePrecision   6;

runTimeModifiable yes;

libs ( "libOpenFOAM.so" "libgroovyBC.so" ) ;
fvSchemes

Code:
ddtSchemes
{
    default         steadyState;
}

gradSchemes
{
    default         Gauss linear;
}

divSchemes
{
    default         none;
    div(phi,U)      Gauss limitedLinearV 1;
    div(phi,T)      Gauss limitedLinear 1;
    div(phi,k)      Gauss limitedLinear 1;
    div(phi,epsilon) Gauss limitedLinear 1;
    div(phi,R)      Gauss limitedLinear 1;
    div(R)          Gauss linear;
    div((nuEff*dev(grad(U).T()))) Gauss linear;
}

laplacianSchemes
{
    default         none;
    laplacian(nuEff,U) Gauss linear uncorrected;
    laplacian((1|A(U)),p_rgh) Gauss linear uncorrected;
    laplacian(kappaEff,T) Gauss linear uncorrected;
    laplacian(DkEff,k) Gauss linear uncorrected;
    laplacian(DepsilonEff,epsilon) Gauss linear uncorrected;
    laplacian(DREff,R) Gauss linear uncorrected;
}

interpolationSchemes
{
    default         linear;
}

snGradSchemes
{
    default         uncorrected;
}

fluxRequired
{
    default         no;
    p_rgh           ;
}
fvSolution

Code:
solvers
{
p_rgh
{
    solver          GAMG;
    tolerance       1e-06;
    relTol          0.01;
    smoother        DIC;
    cacheAgglomeration true;
    nCellsInCoarsestLevel 10;
    agglomerator    faceAreaPair;
    mergeLevels     1;
}

"(U|k|epsilon|R|T)"
{
    solver          PBiCG;
    preconditioner  DILU;
    tolerance       1e-05;
    relTol          0.1;
}
}

SIMPLE
{
    nNonOrthogonalCorrectors 0;
    convergence  1e-3;
    pRefCell 0;
    pRefValue 0;
}

relaxationFactors
{
    p_rgh           0.7;
    U               0.5;
    T               0.5;
    "(k|epsilon|R)" 0.5;
}
bye,
Sebastian
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Old   June 25, 2012, 05:31
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Bernhard Gschaider
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Quote:
Originally Posted by Sebaj View Post
Hi,

Relaxation parameters you mean:

fvSolution

Code:
relaxationFactors
{
    p_rgh           0.7;
    U               0.5;
    T               0.5;
    "(k|epsilon|R)" 0.5;
}
This on. And it looks alright
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Old   June 25, 2012, 13:05
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Sebastian
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Hi, thanks gschaider for interest my case.

It's still only one problem with definition temperature. I want: temp room 300K, "rak" temp 323K on wall, inlet from floor 287K and outlet from "rak" 323K. in first step it's what i want, but then in every next step "rak" temp fall down to 300K.. Any one have idea how to repair my case? what is wrong?
above I gave the link to my case.

Sebastian
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Old   October 31, 2012, 15:16
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Dinesh Balaji
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Hi Sebastian,

I am working on similar stuff. But I am very new to this software. I want to know how did you generate mesh without the blockmeshdict file.
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