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boundary condition issues with rho

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Old   March 5, 2016, 20:35
Default boundary condition issues with rho
  #1
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William Komp
Join Date: Jan 2016
Posts: 4
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HI,
i am trying to setup a simulation with Steady-Compressible Realizeable k-e model. The boundary conditions the y min, ymax, z min and zmax are walls (default settings). For min x [what i want to the inlet] i have Velocity Mass Flow inlet with Mass flow rate of 223.15 kg/s, For pressure i have a fixed value of 101,000Pa. Turbulence i have constant k=1 and e = 1. Temperature is constant at 300K. The outlet I have boundary conditions velocity Pressure Directed Inlet-outlet with the velocity unit components (1,0,0). The pressure and temperature are constants at 101,000Pa and 300K respectively. Turbulence is by turbulence intensity and mixing length with value 0.1 and 1 respectively.

When I run the simulation, I get the simulation crashes after 3 steps. Here is the log file output.

i appreciate all help getting these boundary conditions working.

William

*******************LOG****************************


******************
* Run Case *
******************
Case : /home/parallels/Documents/helyx/Engys/HELYX-OS/v2.3.1/prototype
Procs : -1
Log : /home/parallels/Documents/helyx/Engys/HELYX-OS/v2.3.1/prototype/log/rhoSimpleFoam.log
Env : /opt/openfoam240/etc/bashrc
Vendor : /opt
Paraview :
MachineFile :
Solver : rhoSimpleFoam
/*---------------------------------------------------------------------------*\
| ========= | |
| \\ / F ield | OpenFOAM: The Open Source CFD Toolbox |
| \\ / O peration | Version: 2.4.0 |
| \\ / A nd | Web: www.OpenFOAM.org |
| \\/ M anipulation | |
\*---------------------------------------------------------------------------*/
Build : 2.4.0-f0842aea0e77
Exec : rhoSimpleFoam -case /home/parallels/Documents/helyx/Engys/HELYX-OS/v2.3.1/prototype
Date : Mar 05 2016
Time : 20:33:35
Host : "ubuntu"
PID : 26893
Case : /home/parallels/Documents/helyx/Engys/HELYX-OS/v2.3.1/prototype
nProcs : 1
sigFpe : Enabling floating point exception trapping (FOAM_SIGFPE).
fileModificationChecking : Monitoring run-time modified files using timeStampMaster
allowSystemOperations : Allowing user-supplied system call operations

// * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * //
Create time

Create mesh for time = 0


SIMPLE: convergence criteria
field U tolerance 1e-05
field k tolerance 1e-05
field epsilon tolerance 1e-05
field omega tolerance 1e-05
field nuTilda tolerance 1e-05
field T tolerance 1e-05
field p_rgh tolerance 1e-05
field p tolerance 1e-05

Reading thermophysical properties

Selecting thermodynamics package
{
type hePsiThermo;
mixture pureMixture;
transport const;
thermo hConst;
equationOfState perfectGas;
specie specie;
energy sensibleEnthalpy;
}

Reading field U

--> FOAM Warning :
From function Field<Type>::Field(const word& keyword, const dictionary&, const label)
in file /home/openfoam/OpenFOAM/OpenFOAM-2.4.0/src/OpenFOAM/lnInclude/Field.C at line 318
Reading "/home/parallels/Documents/helyx/Engys/HELYX-OS/v2.3.1/prototype/0/U.boundaryField.ffmaxx" from line 30 to line 32
expected keyword 'uniform' or 'nonuniform', assuming deprecated Field format from Foam version 2.0.
Reading/calculating face flux field phi

Creating turbulence model

Selecting RAS turbulence model realizableKE
realizableKECoeffs
{
label "Realizable k-\u03B5";
fieldMaps
{
k kCompressible;
epsilon epsilonCompressible;
mut mut;
alphat alphatCompressible;
}
Cmu 0.09;
A0 4;
C2 1.9;
sigmak 1;
sigmaEps 1.2;
Prt 1;
}

Creating finite volume options from "system/fvOptions"


Starting time loop

Time = 1

smoothSolver: Solving for Ux, Initial residual = 1, Final residual = 0.05577502687, No Iterations 4
smoothSolver: Solving for Uy, Initial residual = 1, Final residual = 0.0490331879, No Iterations 2
smoothSolver: Solving for Uz, Initial residual = 1, Final residual = 0.05230403557, No Iterations 2
--> FOAM Warning :
From function gaussConvectionScheme
in file finiteVolume/convectionSchemes/gaussConvectionScheme/gaussConvectionScheme.H at line 123
Reading "/home/parallels/Documents/helyx/Engys/HELYX-OS/v2.3.1/prototype/system/fvSchemes.divSchemes.default" at line 42
Unbounded 'Gauss' div scheme used in steady-state solver, use 'bounded Gauss' to ensure boundedness.
To remove this warning switch off 'warnUnboundedGauss' in "/opt/openfoam240/etc/controlDict"
smoothSolver: Solving for h, Initial residual = 0.4542020003, Final residual = 0.5238734912, No Iterations 1000
GAMG: Solving for p, Initial residual = 1, Final residual = 0.002897509487, No Iterations 3
time step continuity errors : sum local = 0.1223415608, global = -0.01575956049, cumulative = -0.01575956049
rho max/min : 1.170208875 1.158796286
smoothSolver: Solving for epsilon, Initial residual = 0.7641809181, Final residual = 0.05056236082, No Iterations 5
smoothSolver: Solving for k, Initial residual = 1, Final residual = 0.08636557269, No Iterations 4
ExecutionTime = 6.89 s ClockTime = 7 s

Time = 2

smoothSolver: Solving for Ux, Initial residual = 0.4856557773, Final residual = 0.04088940812, No Iterations 4
smoothSolver: Solving for Uy, Initial residual = 0.2959478999, Final residual = 0.01708981427, No Iterations 4
smoothSolver: Solving for Uz, Initial residual = 0.2993424134, Final residual = 0.01678456238, No Iterations 4
--> FOAM Warning :
From function gaussConvectionScheme
in file finiteVolume/convectionSchemes/gaussConvectionScheme/gaussConvectionScheme.H at line 123
Reading "/home/parallels/Documents/helyx/Engys/HELYX-OS/v2.3.1/prototype/system/fvSchemes.divSchemes.default" at line 42
Unbounded 'Gauss' div scheme used in steady-state solver, use 'bounded Gauss' to ensure boundedness.
To remove this warning switch off 'warnUnboundedGauss' in "/opt/openfoam240/etc/controlDict"
smoothSolver: Solving for h, Initial residual = 1, Final residual = 0.04306443752, No Iterations 3
GAMG: Solving for p, Initial residual = 0.999979061, Final residual = 0.008006024134, No Iterations 4
time step continuity errors : sum local = 0.1199957599, global = -0.04015948266, cumulative = -0.05591904315
rho max/min : 1.601185824 1.105856471
smoothSolver: Solving for epsilon, Initial residual = 0.9976423838, Final residual = 0.08519837386, No Iterations 6
smoothSolver: Solving for k, Initial residual = 0.01473579867, Final residual = 0.001094065659, No Iterations 3
bounding k, min: -6.268441188 max: 19036010.69 average: 16265.2921
ExecutionTime = 7.9 s ClockTime = 8 s

Time = 3

smoothSolver: Solving for Ux, Initial residual = 0.3101036288, Final residual = 0.02103006195, No Iterations 5
smoothSolver: Solving for Uy, Initial residual = 0.4129887917, Final residual = 0.03287612796, No Iterations 5
smoothSolver: Solving for Uz, Initial residual = 0.4296949519, Final residual = 0.03225943176, No Iterations 5
--> FOAM Warning :
From function gaussConvectionScheme
in file finiteVolume/convectionSchemes/gaussConvectionScheme/gaussConvectionScheme.H at line 123
Reading "/home/parallels/Documents/helyx/Engys/HELYX-OS/v2.3.1/prototype/system/fvSchemes.divSchemes.default" at line 42
Unbounded 'Gauss' div scheme used in steady-state solver, use 'bounded Gauss' to ensure boundedness.
To remove this warning switch off 'warnUnboundedGauss' in "/opt/openfoam240/etc/controlDict"
smoothSolver: Solving for h, Initial residual = 0.2128577791, Final residual = 0.01670512672, No Iterations 8


--> FOAM FATAL ERROR:
Maximum number of iterations exceeded

From function thermo<Thermo, Type>::T(scalar f, scalar T0, scalar (thermo<Thermo, Type>::*F)(const scalar) const, scalar (thermo<Thermo, Type>::*dFdT)(const scalar) const, scalar (thermo<Thermo, Type>::*limit)(const scalar) const) const
in file /home/openfoam/OpenFOAM/OpenFOAM-2.4.0/src/thermophysicalModels/specie/lnInclude/thermoI.H at line 76.

FOAM aborting

#0 Foam::error:rintStack(Foam::Ostream&) at ??:?
#1 Foam::error::abort() at ??:?
#2 Foam::species::thermo<Foam::hConstThermo<Foam:er fectGas<Foam::specie> >, Foam::sensibleEnthalpy>::THs(double, double, double) const at ??:?
#3 Foam::hePsiThermo<Foam:siThermo, Foam:ureMixture<Foam::constTransport<Foam::speci es::thermo<Foam::hConstThermo<Foam:erfectGas<Foa m::specie> >, Foam::sensibleEnthalpy> > > >::calculate() at ??:?
#4 Foam::hePsiThermo<Foam:siThermo, Foam:ureMixture<Foam::constTransport<Foam::speci es::thermo<Foam::hConstThermo<Foam:erfectGas<Foa m::specie> >, Foam::sensibleEnthalpy> > > >::correct() at ??:?
#5 ? at ??:?
#6 __libc_start_main in "/lib/x86_64-linux-gnu/libc.so.6"
#7 ? at ??:?
/home/parallels/Documents/helyx/Engys/HELYX-OS/v2.3.1/prototype/solver_serial.run: line 32: 26893 Aborted (core dumped) $SOLVER -case $CASE 2>&1
26894 Done | tee -a $LOG
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Old   March 6, 2016, 14:16
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Daniel P. Combest
Join Date: Mar 2009
Location: St. Louis, USA
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chegdan will become famous soon enoughchegdan will become famous soon enough
The error message "Maximum number of iterations exceeded" is very common and can be due to many things. The most prevalent being that you are somehow getting a negative pressure or temperature in your system and the newton raphson iterations in the thermo model are not converging. Without looking at the case, it will be difficult to tell you exactly what the problem is. Have you tried simpler BCs on your outlets i.e. fixed pressure, inletOutlet velocity, inletOutlet Temperature?
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