If you havent passsed -66 CAD
If you havent passsed -66 CAD you shouldnt have any combustion yet.
do you have any fuel? |
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!?!
|
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. |
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? |
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? |
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? |
Is there anybody who can help
Is there anybody who can help me ??
Atsushi |
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. |
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 |
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 |
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 |
Hi Tanaka,
You should check
Hi Tanaka,
You should check old log ↓↓ In Preprocessing/FoamX/dieselEngineFoam Good luck! Atsushi |
Atsushi,
Thanks a lot for y
Atsushi,
Thanks a lot for your help. It's now working! |
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 |
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 |
Bruno,
Thanks for your quic
Bruno,
Thanks for your quick answer! Atsu |
Hello,
I want to know Reyno
Hello,
I want to know Reynolds number "Re" and viscosity "μ" of some cells per CA. I found "sampleDict" in stressedFoam/plateHole/system. Can I check "Re" and "μ" in dieselEngineFoam using sampleDict? Thanks. Atsu |
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 |
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. |
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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