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-   -   DieselEngineFoam (https://www.cfd-online.com/Forums/openfoam-pre-processing/62017-dieselenginefoam.html)

niklas January 13, 2006 08:52

If you havent passsed -66 CAD
 
If you havent passsed -66 CAD you shouldnt have any combustion yet.

do you have any fuel?

stefanke January 13, 2006 08:56

with the wedge geometry I run
 
with the wedge geometry I run my simulation from -180 to 180 CA. Fuel is also injected and the temperatures are high enough so combustion process should take place!?!

niklas January 13, 2006 09:29

did you set chemistry on in ch
 
did you set chemistry on in chemistryProperties?

If it doesnt burn you reactions are too slow.
That means that its either turned off or
that the reaction rate constant in chem.inp is too low.

stefanke January 13, 2006 09:38

Niklas, yes chemistry is on
 
Niklas,

yes chemistry is on!

combustionProperties:
---------------------
chemistry on;

chemistrySolver ODE;
//chemistrySolver EulerImplicit;
//chemistrySolver sequential;

initialChemicalTimeStep 1.0e-7;

sequentialCoeffs
{
cTauChem 1.0e-3;
}

EulerImplicitCoeffs
{
cTauChem 5.0e-2;
equilibriumRateLimiter off;
}

ODECoeffs
{
ODESolver SIBS;
eps 5.0e-2;
scale 1.0;
}


I tried the the single step mechanism (chem.inp1) and chem.inp_15 delivered from the dieselFoam tutorial. I think the reation rates of this schemes should be ok or not?

atsushi January 16, 2007 05:42

Hi,everyone Now I try to se
 
Hi,everyone

Now I try to setup dieselEngineFoam.
It seems that there is no definition about injection timing in dieselFoam.
Where and How should I define it?

atsushi January 16, 2007 05:46

Hi,everyone Now I try to se
 
Hi,everyone

Now I try to setup dieselEngineFoam.
It seems that there is no definition about injection timing in dieselFoam.
Where and How should I define it?

atsushi May 17, 2007 02:07

Is there anybody who can help
 
Is there anybody who can help me ??

Atsushi

nishio June 17, 2007 23:22

I run dieselEngineFoam of OF 1
 
I run dieselEngineFoam of OF 1.3.

I got this error message.
--> FOAM FATAL IO ERROR : keyword cyclics is undefined in dictionary "/home/nishio/OpenFOAM/nishio-1.3/run/tutorials/dieselEngineFoam14/cyclic_test/- 180/p::boundaryField"

file: /home/nishio/OpenFOAM/nishio-1.3/run/tutorials/dieselEngineFoam14/cyclic_test/-1 80/p::boundaryField from line 31 to line 45.

From function dictionary::lookupEntry(const word& keyword) const
in file db/dictionary/dictionary.C at line 152.

this is dieselEngineFoam/test/-180/p.
dimensions [ 1 -1 -2 0 0 0 0 ];

internalField uniform 100000;

boundaryField
{
piston
{
type zeroGradient;
}

liner
{
type zeroGradient;
}

cylinderHead
{
type zeroGradient;
}
cyclics...
{
type zeroGradient;
}
}

What is wrong?

Please tell me.
thanks.

hjasak June 17, 2007 23:31

You have either messed up the
 
You have either messed up the brackets or have hidden Microsoft endline characters (Ctrl-M) in the bit which says

cylinderHead
{
type zeroGradient;

cyclics...
{
type zeroGradient;
}
}

By the way, what are those dots after "cyclics"?

As a consequence, the solver cannot find the bit that says "cyclics" to locate the subdictionary.

There may be other things wrong as well, e.g. the boundary condition type on the cyclic boundary should be "cyclic", but the code will tell you what it thinks.

Good luck,

Hrv

nishio June 29, 2007 05:31

I run dieselEngineFoam of tuto
 
I run dieselEngineFoam of tutorials.

Below,I show log dieselEngineFoam.

No Iterations of rho is 0. what happen?

Why this result occured?

Please teach me.

thanks.


Number of parcels in system | 2441
Injected liquid mass....... | 0.585093 mg
Liquid Mass in system...... | 0.556518 mg
SMD, Dmax.................. | 8.04166 mu, 144.482 mu
Added gas mass = 0.0285751 mg
Evaporation Continuity Error| -1.50067e-09 mg
ExecutionTime = 1403.97 s ClockTime = 1405 s

Mean and max Courant Numbers = 6.06171e-05 0.0998279
deltaT = 4.11218e-08
Crank angle = -14.8499 CA-deg
deltaZ = 8.26244e-08
clearance: 0.00709141
Piston speed = 2.00926 m/s
Solving chemistry
diagonal: Solving for rho, Initial residual = 0, Final residual = 0, No Iterati
ons 0
BICCG: Solving for Ux, Initial residual = 0.00112271, Final residual = 6.95297e
-08, No Iterations 1
BICCG: Solving for Uy, Initial residual = 0.00110164, Final residual = 8.77127e
-07, No Iterations 1
BICCG: Solving for Uz, Initial residual = 0.00131305, Final residual = 2.67449e
-07, No Iterations 1
BICCG: Solving for C7H16, Initial residual = 0.00252406, Final residual = 3.952
72e-07, No Iterations 1
BICCG: Solving for O2, Initial residual = 0.00218811, Final residual = 3.20441e
-07, No Iterations 1
BICCG: Solving for CO2, Initial residual = 0.00116516, Final residual = 1.68511
e-07, No Iterations 1
BICCG: Solving for H2O, Initial residual = 0.00116516, Final residual = 1.68511
e-07, No Iterations 1
BICCG: Solving for h, Initial residual = 0.000129235, Final residual = 2.90022e
-08, No Iterations 1
ICCG: Solving for p, Initial residual = 0.0204819, Final residual = 3.29525e-13
, No Iterations 2
diagonal: Solving for rho, Initial residual = 0, Final residual = 0, No Iterati
ons 0
time step continuity errors : sum local = 3.65186e-16, global = 2.63727e-16, cum
ulative = 4.27066e-12
ICCG: Solving for p, Initial residual = 8.59685e-05, Final residual = 2.52916e-
10, No Iterations 1
diagonal: Solving for rho, Initial residual = 0, Final residual = 0, No Iterati
ons 0
time step continuity errors : sum local = 2.56815e-13, global = 7.56819e-15, cum
ulative = 4.27823e-12
BICCG: Solving for epsilon, Initial residual = 0.000555864, Final residual = 6.
98831e-08, No Iterations 1
BICCG: Solving for k, Initial residual = 0.000689, Final residual = 1.17105e-07
, No Iterations 1
Mean pressure:3.45583e+06
Mean temperature:914.791
Mean u':2.51441

tanaka July 19, 2007 04:32

Hello, I try to setup diese
 
Hello,

I try to setup dieselEngineFoam.
Now I don't understand amethod to "merge" the two cases to get a setup for the dieselEngine solver.
I want you to teach it in detail.

Thanks if you can help.

tanaka

atsushi July 20, 2007 03:08

Hi Tanaka, You should check
 
Hi Tanaka,

You should check old log
↓↓
In Preprocessing/FoamX/dieselEngineFoam

Good luck!

Atsushi

tanaka July 26, 2007 08:17

Atsushi, Thanks a lot for y
 
Atsushi,

Thanks a lot for your help.
It's now working!

atsushi September 3, 2007 02:30

Hi, "0" folder in dieselFoa
 
Hi,

"0" folder in dieselFoam ,
I can see "N2:0.766, O2:0.233" composition.

What kind of fraction?
Volume fraction or mass fraction?

Thanks.

Atsushi

frackowi September 4, 2007 11:10

mass fraction. the solvers di
 
mass fraction.
the solvers dieselFoam use it in the equations:
in createFields.
Hfor(label i=0; i<Y.size(); i++)
{
fields.add(Y[i]);
}
in Yeqn
solve
(
fvm::ddt(rho, Yi)
+ mvConvection->fvmDiv(phi, Yi)
- fvm::laplacian(turbulence->muEff(), Yi)
== kappa*chemistry.RR(i),
mesh.solver("Yi")
);
which is the mass conservation equation for a specie i, implying mass fraction Yi

Bruno

atsushi September 5, 2007 04:47

Bruno, Thanks for your quic
 
Bruno,

Thanks for your quick answer!


Atsu

atsushi November 25, 2007 07:38

Hello, I want to know Reyno
 
Hello,

I want to know Reynolds number "Re" and viscosity "&mu;" of some cells per CA.

I found "sampleDict" in stressedFoam/plateHole/system.
Can I check "Re" and "&mu;" in dieselEngineFoam using sampleDict?

Thanks.

Atsu

badiger November 24, 2008 08:01

Hello Sir, I am new OpenFOAM,
 
Hello Sir,
I am new OpenFOAM,

I am trying to implementing Eddy Dissipation Concept, Can any body tell whether it is already there in OpenFOAM-1.5 or still to be implemented,
And give me some guidelines to set up a basic combustion problem in OpenFOAM

markusrehm November 25, 2008 08:22

Hello Badiger, I implemente
 
Hello Badiger,

I implemented it and have done a few test calculations but still it is not in a condition to be published. I hope to do that in a few weeks.

I showed it at the Workshop in Milan this year. If you want to I can send you the slides.

Regards, Markus.

badiger December 3, 2008 02:25

Thanks Markus, Please send,
 
Thanks Markus,

Please send, I ll go through,
Can you guide me in implementing a combustion problm, a simple one, some start ups i have already started with it, but stucking in writing chem.inp file requiring values of Activation energy etc.. for different fuels

Plz do the needful


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