bounded Gauss and normal Gauss question
2 Attachment(s)
Hi all,
I modifyed the flamelet solver (libOpenSmoke) and used the nice feature in the OF 2.2.x for the equations for
 mixture fraction Z
 variance of mixture fraction Z
 enthalpy H
In the old code I implemented the Sp term in the code:
Code:
(
fvm::div(phi, Z)
 fvm::Sp(fvc::div(phi), Z)
 fvm::laplacian(turbulence>muEff()/sigmat, Z)
)
In the new version I used it without:
Code:
(
fvm::div(phi, Z)
 fvm::laplacian(turbulence>muEff()/sigmat, Z)
)
but therefor I added bounded schemes (fvSchemes):
Code:
div(phi,H) bounded Gauss limitedLinear 1;
div(phi,Z) bounded Gauss limitedLimitedLinear 1 0 1;
div(phi,Zvar) bounded Gauss limitedLimitedLinear 1 0 0.25;
This settings give an identical simulation and the validation was 1:1.
OF was warning like:
Code:
> FOAM Warning :
From function gaussConvectionScheme
in file finiteVolume/convectionSchemes/gaussConvectionScheme/gaussConvectionScheme.H at line 123
Reading "/home/shorty/OpenFOAM/shorty2.2.x/flameletModel2.2.x/tutorials/Sandia_COH2N2/system/fvSchemes.divSchemes.div(phi,U)" at line 30
Unbounded 'Gauss' div scheme used in steadystate solver, use 'bounded Gauss' to ensure boundedness.
To remove this warning switch off 'boundedGauss' in "/home/shorty/OpenFOAM/OpenFOAM2.2.x/etc/controlDict"
smoothSolver: Solving for Ux, Initial residual = 0.00265791, Final residual = 1.16588e05, No Iterations 2
smoothSolver: Solving for Uy, Initial residual = 3.76559e05, Final residual = 1.86524e07, No Iterations 2
smoothSolver: Solving for Uz, Initial residual = 0.0056559, Final residual = 4.24363e05, No Iterations 2
GAMG: Solving for p, Initial residual = 0.00227516, Final residual = 7.45788e05, No Iterations 2
time step continuity errors : sum local = 0.0252954, global = 9.16694e05, cumulative = 2.81028
rho max/min : 1.21084 0.176765
smoothSolver: Solving for Z, Initial residual = 5.02383e05, Final residual = 6.15323e07, No Iterations 2
smoothSolver: Solving for Zvar, Initial residual = 4.07254e05, Final residual = 4.37422e08, No Iterations 2
smoothSolver: Solving for H, Initial residual = 5.61876e05, Final residual = 7.14374e07, No Iterations 2
> FOAM Warning :
From function gaussConvectionScheme
in file finiteVolume/convectionSchemes/gaussConvectionScheme/gaussConvectionScheme.H at line 123
Reading "/home/shorty/OpenFOAM/shorty2.2.x/flameletModel2.2.x/tutorials/Sandia_COH2N2/system/fvSchemes.divSchemes.div(phi,epsilon)" at line 31
Unbounded 'Gauss' div scheme used in steadystate solver, use 'bounded Gauss' to ensure boundedness.
To remove this warning switch off 'boundedGauss' in "/home/shorty/OpenFOAM/OpenFOAM2.2.x/etc/controlDict"
smoothSolver: Solving for epsilon, Initial residual = 0.00011511, Final residual = 5.69949e07, No Iterations 2
> FOAM Warning :
From function gaussConvectionScheme
in file finiteVolume/convectionSchemes/gaussConvectionScheme/gaussConvectionScheme.H at line 123
Reading "/home/shorty/OpenFOAM/shorty2.2.x/flameletModel2.2.x/tutorials/Sandia_COH2N2/system/fvSchemes.divSchemes.div(phi,k)" at line 32
Unbounded 'Gauss' div scheme used in steadystate solver, use 'bounded Gauss' to ensure boundedness.
To remove this warning switch off 'boundedGauss' in "/home/shorty/OpenFOAM/OpenFOAM2.2.x/etc/controlDict"
smoothSolver: Solving for k, Initial residual = 0.000112566, Final residual = 8.72544e07, No Iterations 2
ExecutionTime = 651.17 s ClockTime = 654 s
and so I used bounded schemes for all div equations.
If I do that, I get a strange solution (picture).
can someone tell why the values are so different?
picture bound: all schemes are bounded Gauss
picture unbound: only Z,Zvar,H are bounded
Thanks in advance,
Tobi
