CFD Online Discussion Forums - a problem with convergence in buoyantSimpleFoam

Hello!

I'm trying to solve a problem of a flow through a complex geometry(picture is attached).
I was able to mesh my stl geometry and set up the case in HelyxOS. However, when I am trying to solve it with buoyantSimpleFoam, there is no convergence: the residuals start oscillating. Probably it is because of complex geometry. I had the similar problem why I was trying to solve this case in abaqus and i hoped that OpenFOAM will be better, but got the same problem.

log:

Code:

case = /home/sergkuznet/Engys/HELYX-OS/v2.0.0/UCfluidsmall_meshed_compressible

log = /home/sergkuznet/Engys/HELYX-OS/v2.0.0/UCfluidsmall_meshed_compressible/log/buoyantSimpleFoam.log

solver = buoyantSimpleFoam

vendorHome = /opt

environmentLoader = /opt/openfoam222/etc/bashrc

/*---------------------------------------------------------------------------*\

| =========                 |                                                 |

| \\      /  F ield         | OpenFOAM: The Open Source CFD Toolbox           |

|  \\    /   O peration     | Version:  2.2.2                                 |

|   \\  /    A nd           | Web:      www.OpenFOAM.org                      |

|    \\/     M anipulation  |                                                 |

\*---------------------------------------------------------------------------*/

Build  : 2.2.2-9240f8b967db

Exec   : buoyantSimpleFoam -case /home/sergkuznet/Engys/HELYX-OS/v2.0.0/UCfluidsmall_meshed_compressible

Date   : Jan 15 2014

Time   : 23:30:58

Host   : "ubuntu"

PID    : 24661

Case   : /home/sergkuznet/Engys/HELYX-OS/v2.0.0/UCfluidsmall_meshed_compressible

nProcs : 1

sigFpe : Enabling floating point exception trapping (FOAM_SIGFPE).

fileModificationChecking : Monitoring run-time modified files using timeStampMaster

allowSystemOperations : Disallowing user-supplied system call operations



// * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * //

Create time



Create mesh for time = 0





Reading g

Reading thermophysical properties



Selecting thermodynamics package 

{

    type            heRhoThermo;

    mixture         pureMixture;

    transport       const;

    thermo          hConst;

    equationOfState perfectGas;

    specie          specie;

    energy          sensibleEnthalpy;

}



Reading field U



Reading/calculating face flux field phi



Creating turbulence model



Selecting RAS turbulence model kEpsilon

kEpsilonCoeffs

{

    label           "Standard high-Re k-\u03B5";

    fieldMaps

    {

        k               kCompressible;

        epsilon         epsilonCompressible;

        mut             mut;

        alphat          alphatCompressible;

    }

    Cmu             0.09;

    C1              1.44;

    C2              1.92;

    C3              0.85;

    alphah          1.111;

    alphak          1;

    alphaEps        0.76923;

    sigmak          1;

    sigmaEps        1.3;

    Prt             1;

}



Calculating field g.h



Reading field p_rgh



Creating fintite volume options from fvOptions



Radiation model not active: radiationProperties not found

Selecting radiationModel none



SIMPLE: no convergence criteria found. Calculations will run for 50000 steps.





Starting time loop



Time = 1



smoothSolver:  Solving for Ux, Initial residual = 1, Final residual = 0.05456998525, No Iterations 2

smoothSolver:  Solving for Uy, Initial residual = 1, Final residual = 0.04761354967, No Iterations 2

smoothSolver:  Solving for Uz, Initial residual = 1, Final residual = 0.0923876983, No Iterations 2

smoothSolver:  Solving for h, Initial residual = 0.9999999996, Final residual = 0.02860158267, No Iterations 3

GAMG:  Solving for p_rgh, Initial residual = 0.882758416, Final residual = 0.03173471025, No Iterations 4

time step continuity errors : sum local = 0.005249873879, global = -0.000182711125, cumulative = -0.000182711125

rho max/min : 1.158622649 1.142785577

smoothSolver:  Solving for epsilon, Initial residual = 0.1608057626, Final residual = 0.006153099236, No Iterations 2

smoothSolver:  Solving for k, Initial residual = 1, Final residual = 0.03719092912, No Iterations 3

ExecutionTime = 4.76 s  ClockTime = 4 s



Time = 2



smoothSolver:  Solving for Ux, Initial residual = 0.7259532586, Final residual = 0.02361427294, No Iterations 3

smoothSolver:  Solving for Uy, Initial residual = 0.7068399159, Final residual = 0.02238854075, No Iterations 3

smoothSolver:  Solving for Uz, Initial residual = 0.6699165409, Final residual = 0.02056174524, No Iterations 3

smoothSolver:  Solving for h, Initial residual = 0.7405307436, Final residual = 0.02051199796, No Iterations 3

GAMG:  Solving for p_rgh, Initial residual = 0.304082482, Final residual = 0.01050962275, No Iterations 7

time step continuity errors : sum local = 0.1774290497, global = 0.001030155269, cumulative = 0.0008474441436

rho max/min : 1.158650312 1.13997601

smoothSolver:  Solving for epsilon, Initial residual = 0.01048787725, Final residual = 0.000319066845, No Iterations 2

smoothSolver:  Solving for k, Initial residual = 0.7883387769, Final residual = 0.04988614677, No Iterations 2

ExecutionTime = 7.4 s  ClockTime = 7 s



Time = 3



smoothSolver:  Solving for Ux, Initial residual = 0.3011829881, Final residual = 0.00895536283, No Iterations 3

smoothSolver:  Solving for Uy, Initial residual = 0.3393492916, Final residual = 0.03275950006, No Iterations 2

smoothSolver:  Solving for Uz, Initial residual = 0.2385413804, Final residual = 0.007124100008, No Iterations 3

smoothSolver:  Solving for h, Initial residual = 0.2914052321, Final residual = 0.01625010492, No Iterations 2

GAMG:  Solving for p_rgh, Initial residual = 0.8042185927, Final residual = 0.02773146053, No Iterations 4

time step continuity errors : sum local = 0.1888755073, global = 0.006418408439, cumulative = 0.007265852582

rho max/min : 1.15968521 1.137278596

smoothSolver:  Solving for epsilon, Initial residual = 0.01144151224, Final residual = 0.0003601066569, No Iterations 2

smoothSolver:  Solving for k, Initial residual = 0.08325549938, Final residual = 0.00442307674, No Iterations 2

ExecutionTime = 9.86 s  ClockTime = 9 s



Time = 4



smoothSolver:  Solving for Ux, Initial residual = 0.3572870107, Final residual = 0.01098460154, No Iterations 3

smoothSolver:  Solving for Uy, Initial residual = 0.3412253921, Final residual = 0.01018265882, No Iterations 3

smoothSolver:  Solving for Uz, Initial residual = 0.1938818624, Final residual = 0.00590410665, No Iterations 3

smoothSolver:  Solving for h, Initial residual = 0.06609471347, Final residual = 0.004228284277, No Iterations 2

GAMG:  Solving for p_rgh, Initial residual = 0.4711994431, Final residual = 0.02294413812, No Iterations 4

time step continuity errors : sum local = 0.2498850098, global = 0.00713703493, cumulative = 0.01440288751

rho max/min : 1.162113569 1.134617233

smoothSolver:  Solving for epsilon, Initial residual = 0.01412601771, Final residual = 0.000576026232, No Iterations 2

smoothSolver:  Solving for k, Initial residual = 0.05042717657, Final residual = 0.003666382958, No Iterations 2

ExecutionTime = 12.28 s  ClockTime = 12 s

...

Code:

Time = 6893



smoothSolver:  Solving for Ux, Initial residual = 0.001109267103, Final residual = 9.301950987e-05, No Iterations 2

smoothSolver:  Solving for Uy, Initial residual = 0.002552499345, Final residual = 0.0002171982442, No Iterations 2

smoothSolver:  Solving for Uz, Initial residual = 0.001721074846, Final residual = 0.0001393752654, No Iterations 2

smoothSolver:  Solving for h, Initial residual = 0.001774111589, Final residual = 0.0001480908181, No Iterations 2

GAMG:  Solving for p_rgh, Initial residual = 0.02942919705, Final residual = 0.001007022019, No Iterations 2

time step continuity errors : sum local = 0.006661556709, global = -1.051356534e-05, cumulative = 0.0100249542

rho max/min : 1.555319782 1.028572963

smoothSolver:  Solving for epsilon, Initial residual = 0.0006588752087, Final residual = 3.222172574e-05, No Iterations 2

smoothSolver:  Solving for k, Initial residual = 0.001165457605, Final residual = 7.263342197e-05, No Iterations 2

ExecutionTime = 15783.15 s  ClockTime = 15811 s



Time = 6894



smoothSolver:  Solving for Ux, Initial residual = 0.001105061853, Final residual = 9.282106832e-05, No Iterations 2

smoothSolver:  Solving for Uy, Initial residual = 0.002539850795, Final residual = 0.0002170841452, No Iterations 2

smoothSolver:  Solving for Uz, Initial residual = 0.001712852001, Final residual = 0.0001392339211, No Iterations 2

smoothSolver:  Solving for h, Initial residual = 0.001768589731, Final residual = 0.0001480461638, No Iterations 2

GAMG:  Solving for p_rgh, Initial residual = 0.02919360825, Final residual = 0.0009926483288, No Iterations 2

time step continuity errors : sum local = 0.006562854633, global = -3.20007918e-05, cumulative = 0.009992953411

rho max/min : 1.555999036 1.028541909

smoothSolver:  Solving for epsilon, Initial residual = 0.0006562511602, Final residual = 3.206656798e-05, No Iterations 2

smoothSolver:  Solving for k, Initial residual = 0.001165405109, Final residual = 7.245995858e-05, No Iterations 2

ExecutionTime = 15785.4 s  ClockTime = 15814 s



Time = 6895



smoothSolver:  Solving for Ux, Initial residual = 0.00109332315, Final residual = 9.182453762e-05, No Iterations 2

smoothSolver:  Solving for Uy, Initial residual = 0.002532421163, Final residual = 0.0002170932441, No Iterations 2

smoothSolver:  Solving for Uz, Initial residual = 0.001705007101, Final residual = 0.0001390125982, No Iterations 2

smoothSolver:  Solving for h, Initial residual = 0.001764165224, Final residual = 0.0001480728942, No Iterations 2

GAMG:  Solving for p_rgh, Initial residual = 0.0289295584, Final residual = 0.000999707326, No Iterations 2

time step continuity errors : sum local = 0.006605380848, global = -9.827082398e-06, cumulative = 0.009983126328

rho max/min : 1.557878892 1.028510636

smoothSolver:  Solving for epsilon, Initial residual = 0.0006530257994, Final residual = 3.188133514e-05, No Iterations 2

smoothSolver:  Solving for k, Initial residual = 0.001162685421, Final residual = 7.23104506e-05, No Iterations 2

ExecutionTime = 15787.71 s  ClockTime = 15816 s

....

Code:

Time = 13613



smoothSolver:  Solving for Ux, Initial residual = 0.0005045956734, Final residual = 4.340934053e-05, No Iterations 2

smoothSolver:  Solving for Uy, Initial residual = 0.001157194444, Final residual = 0.0001049946357, No Iterations 2

smoothSolver:  Solving for Uz, Initial residual = 0.000840632502, Final residual = 7.075824151e-05, No Iterations 2

smoothSolver:  Solving for h, Initial residual = 0.0008323391129, Final residual = 7.193982016e-05, No Iterations 2

GAMG:  Solving for p_rgh, Initial residual = 0.01360653861, Final residual = 0.0004963259508, No Iterations 2

time step continuity errors : sum local = 0.003249437982, global = 3.573092127e-05, cumulative = 0.01659601022

rho max/min : 1.620925196 1.026426236

smoothSolver:  Solving for epsilon, Initial residual = 0.0003452632898, Final residual = 1.733068307e-05, No Iterations 2

smoothSolver:  Solving for k, Initial residual = 0.0005906923144, Final residual = 4.027091396e-05, No Iterations 2

ExecutionTime = 31148.92 s  ClockTime = 31204 s



Time = 13614



smoothSolver:  Solving for Ux, Initial residual = 0.000506167618, Final residual = 4.357008435e-05, No Iterations 2

smoothSolver:  Solving for Uy, Initial residual = 0.001159136638, Final residual = 0.0001051976481, No Iterations 2

smoothSolver:  Solving for Uz, Initial residual = 0.0008379983297, Final residual = 7.044233602e-05, No Iterations 2

smoothSolver:  Solving for h, Initial residual = 0.0008271563341, Final residual = 7.156204547e-05, No Iterations 2

GAMG:  Solving for p_rgh, Initial residual = 0.01359108374, Final residual = 0.0004953122914, No Iterations 2

time step continuity errors : sum local = 0.003242773843, global = 3.226945802e-05, cumulative = 0.01662827968

rho max/min : 1.621060156 1.026379888

smoothSolver:  Solving for epsilon, Initial residual = 0.0003443170465, Final residual = 1.723312939e-05, No Iterations 2

smoothSolver:  Solving for k, Initial residual = 0.0005895732474, Final residual = 4.006604868e-05, No Iterations 2

ExecutionTime = 31151.27 s  ClockTime = 31206 s

Code:

Time = 18885



smoothSolver:  Solving for Ux, Initial residual = 0.0006130175635, Final residual = 4.984637275e-05, No Iterations 2

smoothSolver:  Solving for Uy, Initial residual = 0.00146555805, Final residual = 0.0001198237563, No Iterations 2

smoothSolver:  Solving for Uz, Initial residual = 0.001049220622, Final residual = 8.563853344e-05, No Iterations 2

smoothSolver:  Solving for h, Initial residual = 0.001103103009, Final residual = 9.056864292e-05, No Iterations 2

GAMG:  Solving for p_rgh, Initial residual = 0.01792917561, Final residual = 0.0006453816647, No Iterations 2

time step continuity errors : sum local = 0.004211850033, global = -4.69373984e-05, cumulative = 0.02838930114

rho max/min : 1.61685718 1.027702955

smoothSolver:  Solving for epsilon, Initial residual = 0.0003757520635, Final residual = 1.640617344e-05, No Iterations 2

smoothSolver:  Solving for k, Initial residual = 0.0006832165346, Final residual = 4.135313509e-05, No Iterations 2

ExecutionTime = 43243.93 s  ClockTime = 43321 s



Time = 18886



smoothSolver:  Solving for Ux, Initial residual = 0.0006085962287, Final residual = 4.947465059e-05, No Iterations 2

smoothSolver:  Solving for Uy, Initial residual = 0.001453701216, Final residual = 0.0001189017535, No Iterations 2

smoothSolver:  Solving for Uz, Initial residual = 0.001041301996, Final residual = 8.489900064e-05, No Iterations 2

smoothSolver:  Solving for h, Initial residual = 0.001102059566, Final residual = 9.050933718e-05, No Iterations 2

GAMG:  Solving for p_rgh, Initial residual = 0.01782668781, Final residual = 0.0006434618934, No Iterations 2

time step continuity errors : sum local = 0.004199870883, global = -1.300348859e-05, cumulative = 0.02837629765

rho max/min : 1.61575725 1.027666084

smoothSolver:  Solving for epsilon, Initial residual = 0.0003726036192, Final residual = 1.624410955e-05, No Iterations 2

smoothSolver:  Solving for k, Initial residual = 0.0006769270182, Final residual = 4.100176601e-05, No Iterations 2

ExecutionTime = 43246.23 s  ClockTime = 43324 s



Time = 18887



smoothSolver:  Solving for Ux, Initial residual = 0.0006047473189, Final residual = 4.917024084e-05, No Iterations 2

smoothSolver:  Solving for Uy, Initial residual = 0.001440066594, Final residual = 0.0001178240974, No Iterations 2

smoothSolver:  Solving for Uz, Initial residual = 0.001033277701, Final residual = 8.422450783e-05, No Iterations 2

smoothSolver:  Solving for h, Initial residual = 0.001099930259, Final residual = 9.044716316e-05, No Iterations 2

GAMG:  Solving for p_rgh, Initial residual = 0.01778140607, Final residual = 0.0006504819822, No Iterations 2

time step continuity errors : sum local = 0.004246140865, global = 3.962517019e-05, cumulative = 0.02841592282

rho max/min : 1.614670092 1.02762854

smoothSolver:  Solving for epsilon, Initial residual = 0.000369558813, Final residual = 1.612523952e-05, No Iterations 2

smoothSolver:  Solving for k, Initial residual = 0.0006713037785, Final residual = 4.069978604e-05, No Iterations 2

ExecutionTime = 43248.55 s  ClockTime = 43326 s

I wonder if some one can advise me how to tune the solver to get convergence?
Thank you!