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October 2, 2008, 06:44 
Hello!
I have a problem wit

#101 
New Member
Johan Svensson
Join Date: Mar 2009
Posts: 10
Rep Power: 9 
Hello!
I have a problem with the engineFoam tutorial and hope that someone here is able to give me some advice. My task is to simulate a multispark ignition in a SI engine. So I am using the engineFoam/kivaTest case. When I have three ignitions at 30, 20 and 10 deg before TDC it crashes at 7.5 deg before TDC (timestep= 0.01), but with one ignition at 10 before TDC the computation goes on till 40 deg after TDC as I have chosen in the controlDict file. Am I supposed to use the controlDict.1st and controlDict.2nd for this, or when to use them? I don't understand what kind of geometry I am supposed to generate in the polyMesh directory (there is already a mesh of a cylinder when using paraFoam). Now I have generated a small refined cubic mesh because I am interested in the spark in such a volume directly below the spark plug, but I am not sure at all about what mesh to produce and in that case how to place it in the right position below the spark position, and then what boundary conditions to use. Thanks in advance, Johan 

January 13, 2009, 03:46 
Hi!
Is there anyone who can

#102 
New Member
Johan Svensson
Join Date: Mar 2009
Posts: 10
Rep Power: 9 
Hi!
Is there anyone who can give me some references to literature about the physical model that engineFoam is built on? In the beginning of this thread some links are mentioned but unfortunately they don't work. I am doing my master thesis and need to add some background theory about engineFoam to my report. Kind regards, Johan 

March 11, 2009, 08:59 
Hi. I'm trying to implement th

#103 
New Member
John Paul Handrigan
Join Date: Mar 2009
Location: Ottawa, Ontario, Canada
Posts: 16
Rep Power: 9 
Hi. I'm trying to implement the Eddy Breakup Model in OpenFOAM. I'm just wondering if anyone has successfully done this before? Thanks.
JPH 

March 23, 2009, 08:57 
Simulation of 1/4 of a combustion chamber?

#104 
Member
Tomislav Sencic
Join Date: Mar 2009
Posts: 42
Rep Power: 9 
Hello,
I am using dieselFoam to simulate the injection and combustion of fuel in a constant volume chamber. When I try to simulate just a quarter of the chamber to save calculation time (wity sym boundaries and the injector in 0,0,0 position) I get a 4x greater pressure rise. If I would inject just 1/4 of the fuel mass, the spray properties, and evaporation rate would change, it would be a different condition! How can I simulate just 1/4 of the injectin chamber? Tomislav 

March 23, 2009, 10:02 

#105  
Super Moderator
Niklas Nordin
Join Date: Mar 2009
Location: Stockholm, Sweden
Posts: 693
Rep Power: 21 
Quote:
Everything is the same except for the mass in injectionProperties. And I think you should use cyclic bc's and not symmetric. 

March 25, 2009, 13:44 
Modelling Sandia's Flame D

#106 
New Member
John Paul Handrigan
Join Date: Mar 2009
Location: Ottawa, Ontario, Canada
Posts: 16
Rep Power: 9 
Hi. I'm trying to model Sandia's Flame D in openFoam. However, the flame seems to blow off with the current model. I'm using reactingFoam as the solver. Has anyone had a similar experience to this?
Here's a site with more information about Flame D. http://www.ca.sandia.gov/TNF/DataArch/FlameD.html Thanks in advance for any advice you may have! John Paul Handrigan 

March 25, 2009, 14:30 

#107 
Member
M. Mahdi Salehi
Join Date: Mar 2009
Location: Vancouver, BC, Canada
Posts: 50
Rep Power: 9 
Hi John,
I had the experience of simulating a Pilot flame like Sandia D, but it was premixed, I used reactingFoam. I had the same problem by using simple onestep chemistry. I used a 5step chemistry and then I could get a converged solution. However, the solution was not satisfactory. Such flames are highly stained; thus, require good closure for turbulence chemistry interactions. I can give you the 5tep chemisty that I used if you want. cheers, Mahdi 

March 25, 2009, 15:15 
Sandia

#108  
New Member
John Paul Handrigan
Join Date: Mar 2009
Location: Ottawa, Ontario, Canada
Posts: 16
Rep Power: 9 
Quote:
I'd really appreciate the 5step chemistry that you used. How can I get this information from you? email? My email address is jhand085@uottawa.ca . Thanks for the quick reply! John Paul 

April 24, 2010, 14:05 
Those links are not working

#109  
New Member
Ramesh
Join Date: Aug 2009
Posts: 4
Rep Power: 9 
Hello Henry,
Links given by you are not working, kindly help me I want the report on which XiFoam is based. I am working on turbulent premixed flames.I also want to know about these reactants,products & burnt products in thermophysicalProperties file of moriyoHomogeneous case. kindly help me. If I want any other hydrocarbon instaed of propane, what values I shall change here in thermophysicalProperties file,. Thanks in Advance Ramesh Kingston University London Quote:


June 25, 2011, 12:03 

#110 
New Member
Francesca
Join Date: Feb 2011
Posts: 10
Rep Power: 7 
Hello Henry,
just like Ramesh I would like to know something about the bXi model but the links you gave a bit time ago do not work. Could you send me some informations or docs about it? My email adress is: francesca.scaramuzzino86@gmail.com Thanks a lot Francesca 

October 24, 2011, 06:17 

#111  
New Member
Join Date: Jan 2011
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Quote:


November 24, 2011, 11:31 
premixed heptaneair combustion in a diesel engine (HCCI)

#112 
Member
Ayhan Eses
Join Date: Mar 2009
Posts: 35
Rep Power: 9 
Dear Foamers/masters,
I would like to model premixed heptaneair combustion in a diesel engine (HCCI).
Code:
C7H16 + 11O2 => 7CO2 + 8H2O 5.00E+8 0.0 15780.0! 1
I used decomposePar Code:
numberOfSubdomains 8; method simple; simpleCoeffs { n (4 2 1); delta 0.001; } The time period between (180) and (35) seems reasonable. It's ok. When it came to (35) on 22.Nov.201118.41 I changed controlDict files to reduce Co number. //for (180,35) deltaT 0.05; //for (35, 30) deltaT 2.5e06; //for (180,35) writeInterval 5.0; //for (35, 30) writeInterval 1.0; //for (180,35) adjustTimeStep no; //for (35, 30) adjustTimeStep yes; It was started(from 35) again 22.Nov.201119.12 It came to 19.999787 22.Nov.201121.40 The time period between (35) (19.999787) seems reasonable. It's ok. Pressure and temperature values seem normal. But now on 24.Nov.201116.26 it is at 19.7257779 and still running. Just 0,2740091 degree difference took 1 day 18 hour 46 min. time period. Is that last situation normal? What should I do to fix this? I tried to describe my problem more clearly. I hope you understand what I mean. If you give any suggestion/solution, I would be very pleased. I am looking forward to hearing from you soon. Thanks in advance. Best regards. Ayhan  engineCompRatio Code:
ayhan@ayhan:~/Masaüstü/tutorials öğesine bağlantı/dizelim201512N8islemci22112011$ engineCompRatio /**\  =========    \\ / F ield  OpenFOAM: The Open Source CFD Toolbox   \\ / O peration  Version: 2.0.1   \\ / A nd  Web: www.OpenFOAM.com   \\/ M anipulation   \**/ Build : 2.0.151f1de99a4bc Exec : engineCompRatio Date : Nov 24 2011 Time : 14:52:32 Host : ayhan PID : 1614 Case : /home/ayhan/OpenFOAM/ayhan2.0.1/run/tutorials/dizelim201512N8islemci22112011 nProcs : 1 sigFpe : Enabling floating point exception trapping (FOAM_SIGFPE). fileModificationChecking : Monitoring runtime modified files using timeStampMaster allowSystemOperations : Disallowing usersupplied system call operations // * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * // Create engine time Create mesh for time = 180 Selecting engineMesh layered deckHeight: 0.0617697 piston position: 0.00374205 CA = 180 deltaZ = 0 clearance: 0.0655117 Piston speed = 0 m/s CA = 360 deltaZ = 0.068 clearance: 0.00248827 Piston speed = 4.98667 m/s Vmax = 0.000408381, Vmin = 2.66865e05 Vmax/Vmin = 15.3029 End Code:
checkMesh Code:
ayhan@ayhan:~/Masaüstü/tutorials öğesine bağlantı/dizelim201512N8islemci22112011$ checkMesh /**\  =========    \\ / F ield  OpenFOAM: The Open Source CFD Toolbox   \\ / O peration  Version: 2.0.1   \\ / A nd  Web: www.OpenFOAM.com   \\/ M anipulation   \**/ Build : 2.0.151f1de99a4bc Exec : checkMesh Date : Nov 24 2011 Time : 14:53:11 Host : ayhan PID : 1625 Case : /home/ayhan/OpenFOAM/ayhan2.0.1/run/tutorials/dizelim201512N8islemci22112011 nProcs : 1 sigFpe : Enabling floating point exception trapping (FOAM_SIGFPE). fileModificationChecking : Monitoring runtime modified files using timeStampMaster allowSystemOperations : Disallowing usersupplied system call operations // * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * // Create time Create polyMesh for time = 180 Time = 180 Mesh stats points: 32397 faces: 87320 internal faces: 77944 cells: 27544 boundary patches: 4 point zones: 0 face zones: 1 cell zones: 1 Overall number of cells of each type: hexahedra: 27544 prisms: 0 wedges: 0 pyramids: 0 tet wedges: 0 tetrahedra: 0 polyhedra: 0 Checking topology... Boundary definition OK. Cell to face addressing OK. Point usage OK. Upper triangular ordering OK. Face vertices OK. *Number of regions: 2 The mesh has multiple regions which are not connected by any face. <<Writing region information to "180/cellToRegion" Checking patch topology for multiply connected surfaces ... Patch Faces Points Surface topology liner 2596 2866 ok (nonclosed singly connected) piston 1326 1400 ok (nonclosed singly connected) cylinderHead 2184 2260 ok (nonclosed singly connected) defaultexterior 3270 3421 ok (nonclosed singly connected) Checking geometry... Overall domain bounding box (0.04301 0.0429955 0.00721194) (0.04301 0.0429955 0.0679594) Mesh (nonempty, nonwedge) directions (1 1 1) Mesh (nonempty) directions (1 1 1) Boundary openness (1.58789e19 2.28627e19 1.8564e19) OK. Max cell openness = 2.43625e16 OK. Max aspect ratio = 28.098 OK. Minumum face area = 1.24075e07. Maximum face area = 2.97139e05. Face area magnitudes OK. Min volume = 1.03618e10. Max volume = 9.1877e08. Total volume = 0.000408381. Cell volumes OK. Mesh nonorthogonality Max: 83.9266 average: 30.6664 *Number of severely nonorthogonal faces: 1724. Nonorthogonality check OK. <<Writing 1724 nonorthogonal faces to set nonOrthoFaces Face pyramids OK. Max skewness = 3.36545 OK. Mesh OK. End log Code:
/**\  =========    \\ / F ield  OpenFOAM: The Open Source CFD Toolbox   \\ / O peration  Version: 2.0.x   \\ / A nd  Web: www.OpenFOAM.org   \\/ M anipulation   \**/ Build : 2.0.x29c61267b203 Exec : dizelim2015 parallel Date : Nov 22 2011 Time : 16:52:32 Host : d135.uybhmitu.edu PID : 3461 Case : dizelim201512N8islemci22112011 nProcs : 8 Slaves : 7 ( : : : : : ) Pstream initialized with: floatTransfer : 0 nProcsSimpleSum : 0 commsType : nonBlocking sigFpe : Enabling floating point exception trapping (FOAM_SIGFPE). fileModificationChecking : Monitoring runtime modified files using timeStampMaster allowSystemOperations : Disallowing usersupplied system call operations // * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * // Create engine time Create mesh for time = 180 Selecting engineMesh layered deckHeight: 0.0617697 piston position: 0.00374205 Reading thermophysicalProperties Selecting psiChemistryModel ODEChemistryModel<gasThermoPhysics> Selecting thermodynamics package hsPsiMixtureThermo<reactingMixture<gasThermoPhysics>> Selecting chemistryReader chemkinReader ODEChemistryModel: Number of species = 5 and reactions = 1 Selecting ODE solver SIBS Reading field U Reading/calculating face flux field phi Creating turbulence model. Selecting turbulence model type RASModel Selecting RAS turbulence model kEpsilon kEpsilonCoeffs { Cmu 0.09; C1 1.44; C2 1.92; C3 0.33; sigmak 1; sigmaEps 1.3; Prt 1; } Creating field DpDt Reading g Reading combustion properties Courant Number mean: 0 max: 0 Total cylinder mass: 0.0003676 PIMPLE: no residual control data found. Calculations will employ 3 corrector loops Starting time loop Courant Number mean: 0 max: 0 Krank acisi = 179.95 KAderece deltaZ = 9.21597e09 clearance: 0.0655117 Piston speed = 0.00243302 m/s Solving chemistry , T = 373, p = 95600, C7H16 = 0.0169514 diagonal: Solving for rho, Initial residual = 0, Final residual = 0, No Iterations 0 diagonal: Solving for rho, Initial residual = 0, Final residual = 0, No Iterations 0 diagonal: Solving for rho, Initial residual = 0, Final residual = 0, No Iterations 0 diagonal: Solving for rho, Initial residual = 0, Final residual = 0, No Iterations 0 diagonal: Solving for rho, Initial residual = 0, Final residual = 0, No Iterations 0 PIMPLE: iteration 1 DILUPBiCG: Solving for C7H16, Initial residual = 0.999971, Final residual = 6.261e14, No Iterations 9 DILUPBiCG: Solving for O2, Initial residual = 1, Final residual = 6.26118e14, No Iterations 9 DILUPBiCG: Solving for CO2, Initial residual = 1, Final residual = 6.26118e14, No Iterations 9 DILUPBiCG: Solving for H2O, Initial residual = 1, Final residual = 6.26118e14, No Iterations 9 DILUPBiCG: Solving for hs, Initial residual = 1, Final residual = 0.00217333, No Iterations 1 DICPCG: Solving for p, Initial residual = 1, Final residual = 0.0580049, No Iterations 2 DICPCG: Solving for p, Initial residual = 0.0412122, Final residual = 0.00206164, No Iterations 2 diagonal: Solving for rho, Initial residual = 0, Final residual = 0, No Iterations 0 diagonal: Solving for rho, Initial residual = 0, Final residual = 0, No Iterations 0 diagonal: Solving for rho, Initial residual = 0, Final residual = 0, No Iterations 0 diagonal: Solving for rho, Initial residual = 0, Final residual = 0, No Iterations 0 diagonal: Solving for rho, Initial residual = 0, Final residual = 0, No Iterations 0 time step continuity errors : sum local = 1.57257e08, global = 5.55614e09, cumulative = 5.55614e09 PIMPLE: iteration 2 DILUPBiCG: Solving for C7H16, Initial residual = 0.0028216, Final residual = 5.7904e13, No Iterations 8 DILUPBiCG: Solving for O2, Initial residual = 0.0014441, Final residual = 1.22784e13, No Iterations 8 DILUPBiCG: Solving for CO2, Initial residual = 3.55091e05, Final residual = 7.97566e13, No Iterations 6 DILUPBiCG: Solving for H2O, Initial residual = 3.55084e05, Final residual = 7.97231e13, No Iterations 6 DILUPBiCG: Solving for hs, Initial residual = 0.0336152, Final residual = 7.63924e05, No Iterations 1 DICPCG: Solving for p, Initial residual = 0.0497545, Final residual = 0.00252405, No Iterations 2 DICPCG: Solving for p, Initial residual = 0.00501676, Final residual = 0.000458723, No Iterations 2 diagonal: Solving for rho, Initial residual = 0, Final residual = 0, No Iterations 0 diagonal: Solving for rho, Initial residual = 0, Final residual = 0, No Iterations 0 diagonal: Solving for rho, Initial residual = 0, Final residual = 0, No Iterations 0 diagonal: Solving for rho, Initial residual = 0, Final residual = 0, No Iterations 0 diagonal: Solving for rho, Initial residual = 0, Final residual = 0, No Iterations 0 time step continuity errors : sum local = 4.25382e09, global = 1.59641e09, cumulative = 7.15255e09 PIMPLE: iteration 3 DILUPBiCG: Solving for C7H16, Initial residual = 0.00257326, Final residual = 2.46875e13, No Iterations 8 DILUPBiCG: Solving for O2, Initial residual = 0.00139858, Final residual = 4.01771e13, No Iterations 8 DILUPBiCG: Solving for CO2, Initial residual = 4.88702e07, Final residual = 2.08857e15, No Iterations 6 DILUPBiCG: Solving for H2O, Initial residual = 4.8861e07, Final residual = 2.10063e15, No Iterations 6 DILUPBiCG: Solving for hs, Initial residual = 0.00744226, Final residual = 2.14878e06, No Iterations 2 DICPCG: Solving for p, Initial residual = 0.011001, Final residual = 0.000754799, No Iterations 2 DICPCG: Solving for p, Initial residual = 0.00141697, Final residual = 6.05589e05, No Iterations 3 diagonal: Solving for rho, Initial residual = 0, Final residual = 0, No Iterations 0 diagonal: Solving for rho, Initial residual = 0, Final residual = 0, No Iterations 0 diagonal: Solving for rho, Initial residual = 0, Final residual = 0, No Iterations 0 diagonal: Solving for rho, Initial residual = 0, Final residual = 0, No Iterations 0 diagonal: Solving for rho, Initial residual = 0, Final residual = 0, No Iterations 0 time step continuity errors : sum local = 5.87022e10, global = 3.09467e10, cumulative = 7.46201e09 DILUPBiCG: Solving for epsilon, Initial residual = 0.00173338, Final residual = 2.16273e06, No Iterations 1 DILUPBiCG: Solving for k, Initial residual = 1, Final residual = 6.99123e07, No Iterations 4 Mean pressure:95600.1 Mean temperature:373 Mean u':1.63224 ExecutionTime = 1.63 s ClockTime = 5 s : : : : : Courant Number mean: 0.00451027 max: 0.0533268 Krank acisi = 35 KAderece deltaZ = 2.11031e05 clearance: 0.00528321 Piston speed = 5.57122 m/s Solving chemistry , T = 382.207, p = 96283.4, C7H16 = 0.0169512 diagonal: Solving for rho, Initial residual = 0, Final residual = 0, No Iterations 0 diagonal: Solving for rho, Initial residual = 0, Final residual = 0, No Iterations 0 diagonal: Solving for rho, Initial residual = 0, Final residual = 0, No Iterations 0 diagonal: Solving for rho, Initial residual = 0, Final residual = 0, No Iterations 0 diagonal: Solving for rho, Initial residual = 0, Final residual = 0, No Iterations 0 PIMPLE: iteration 1 DILUPBiCG: Solving for C7H16, Initial residual = 0.0645808, Final residual = 1.43178e13, No Iterations 8 DILUPBiCG: Solving for O2, Initial residual = 0.0645809, Final residual = 1.46181e13, No Iterations 8 DILUPBiCG: Solving for CO2, Initial residual = 0.0645809, Final residual = 2.20095e13, No Iterations 8 DILUPBiCG: Solving for H2O, Initial residual = 0.0645809, Final residual = 2.20095e13, No Iterations 8 DILUPBiCG: Solving for hs, Initial residual = 0.0426634, Final residual = 8.38464e05, No Iterations 1 DICPCG: Solving for p, Initial residual = 0.005583, Final residual = 0.000483398, No Iterations 4 DICPCG: Solving for p, Initial residual = 0.000500225, Final residual = 4.84631e05, No Iterations 6 diagonal: Solving for rho, Initial residual = 0, Final residual = 0, No Iterations 0 diagonal: Solving for rho, Initial residual = 0, Final residual = 0, No Iterations 0 diagonal: Solving for rho, Initial residual = 0, Final residual = 0, No Iterations 0 diagonal: Solving for rho, Initial residual = 0, Final residual = 0, No Iterations 0 diagonal: Solving for rho, Initial residual = 0, Final residual = 0, No Iterations 0 time step continuity errors : sum local = 0.000117224, global = 4.3641e05, cumulative = 0.0103119 PIMPLE: iteration 2 DILUPBiCG: Solving for C7H16, Initial residual = 3.78284e05, Final residual = 6.74487e14, No Iterations 6 DILUPBiCG: Solving for O2, Initial residual = 3.78292e05, Final residual = 9.34363e14, No Iterations 6 DILUPBiCG: Solving for CO2, Initial residual = 3.78292e05, Final residual = 7.20297e14, No Iterations 7 DILUPBiCG: Solving for H2O, Initial residual = 3.78292e05, Final residual = 7.20297e14, No Iterations 7 DILUPBiCG: Solving for hs, Initial residual = 0.000366113, Final residual = 9.65849e06, No Iterations 1 DICPCG: Solving for p, Initial residual = 0.000138196, Final residual = 1.03483e05, No Iterations 5 DICPCG: Solving for p, Initial residual = 2.80019e05, Final residual = 2.65778e06, No Iterations 5 diagonal: Solving for rho, Initial residual = 0, Final residual = 0, No Iterations 0 diagonal: Solving for rho, Initial residual = 0, Final residual = 0, No Iterations 0 diagonal: Solving for rho, Initial residual = 0, Final residual = 0, No Iterations 0 diagonal: Solving for rho, Initial residual = 0, Final residual = 0, No Iterations 0 diagonal: Solving for rho, Initial residual = 0, Final residual = 0, No Iterations 0 time step continuity errors : sum local = 6.43053e06, global = 2.95708e06, cumulative = 0.0103149 PIMPLE: iteration 3 DILUPBiCG: Solving for C7H16, Initial residual = 3.31784e05, Final residual = 1.54592e13, No Iterations 6 DILUPBiCG: Solving for O2, Initial residual = 3.31791e05, Final residual = 8.57671e14, No Iterations 6 DILUPBiCG: Solving for CO2, Initial residual = 3.31791e05, Final residual = 5.75564e13, No Iterations 6 DILUPBiCG: Solving for H2O, Initial residual = 3.31791e05, Final residual = 5.75564e13, No Iterations 6 DILUPBiCG: Solving for hs, Initial residual = 0.000153014, Final residual = 3.74179e07, No Iterations 1 DICPCG: Solving for p, Initial residual = 2.08601e05, Final residual = 1.8431e06, No Iterations 5 DICPCG: Solving for p, Initial residual = 5.37536e06, Final residual = 6.35646e07, No Iterations 4 diagonal: Solving for rho, Initial residual = 0, Final residual = 0, No Iterations 0 diagonal: Solving for rho, Initial residual = 0, Final residual = 0, No Iterations 0 diagonal: Solving for rho, Initial residual = 0, Final residual = 0, No Iterations 0 diagonal: Solving for rho, Initial residual = 0, Final residual = 0, No Iterations 0 diagonal: Solving for rho, Initial residual = 0, Final residual = 0, No Iterations 0 time step continuity errors : sum local = 1.53798e06, global = 2.68049e07, cumulative = 0.0103151 DILUPBiCG: Solving for epsilon, Initial residual = 0.00263629, Final residual = 4.19019e06, No Iterations 1 DILUPBiCG: Solving for k, Initial residual = 0.00292238, Final residual = 8.76681e06, No Iterations 1 Mean pressure:2.14728e+06 Mean temperature:974.471 Mean u':1.69924 ExecutionTime = 3810.6 s ClockTime = 6535 s Last edited by ayhan515; November 24, 2011 at 15:34. 

December 18, 2011, 02:08 
Running a noncombustion case with dieselEngineFoam

#113 
New Member
Carl
Join Date: Dec 2011
Posts: 8
Rep Power: 7 
Dear Foamers,
I am currently running a motored case simulation with dieselEngineFoam. I delayed the SOI to very late so that no fuel is delivered with the 1st cycle (180 to 180). However, the simulation seemed to stop at Top Dead Centre because the timestep did not progress anymore after I waited for quite some time. No error message appeared in the log file and hence I couldn’t really sort of the reason. I anyhow observed that the piston speed and deltaZ turned into negative numbers when the piston reaches TDC. Courant Number mean: 0.00302152 max: 0.247541 deltaT = 5.14141e07 Crank angle = 0.0238475 CAdeg deltaZ = 2.36259e09 clearance: 0.00210001 Piston speed = 0.00459523 m/s Can anyone give me a little advice why did the simulation just ‘stop’ at TDC? The following are my input for blockMeshDict, boundary.org, engineGeometry, pressure boundary condition as well as the controlDict file. For all the boundary conditions, I basically added ‘cyclic’ for ‘cyclic patch’ and ‘empty’ for ‘empty patch’. Am I correct to set so? Many thanks in advance. It would be a great help if anyone of you could point out my mistakes in the input. Thanks again. Best regards, Carl. blockMeshDict // * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * // convertToMeters 0.01; vertices ( (0 0 0) //Vertex 0 (0.187132 0.451777 0) //Vertex 1 (1.871321 4.517771 0) //Vertex 2 (0 0 1.55) //Vertex 3 (0.187132 0.451777 1.55) //Vertex 4 (1.871321 4.517771 1.55) //Vertex 5 (0.187132 0.451777 0) //Vertex 6 (1.871321 4.517771 0) //Vertex 7 (0.187132 0.451777 1.55) //Vertex 8 (1.871321 4.517771 1.55) //Vertex 9 (0 0 17) //Vertex 10 (0.187132 0.451777 17) //Vertex 11 (1.871321 4.517771 17) //Vertex 12 (2.673044 6.453299 17) //Vertex 13 (0.187132 0.451777 17) //Vertex 14 (1.871321 4.517771 17) //Vertex 15 (2.673044 6.453299 17) //Vertex 16 (2.673044 6.453299 1.55) //Vertex 17 (2.673044 6.453299 1.55) //Vertex 18 ); blocks ( hex (1 0 0 6 4 3 3 8) (3 19 5) simpleGrading (1 1 1) //prism for bowl hex (2 1 6 7 5 4 8 9) (15 19 5) simpleGrading (1 1 1) //hex for bowl hex (4 3 3 8 11 10 10 14) (3 19 52) simpleGrading (1 1 1) //prism for main stroke hex (5 4 8 9 12 11 14 15) (15 19 52) simpleGrading (1 1 1) //hex for main stroke inner hex (17 5 9 18 13 12 15 16) (7 19 52) simpleGrading (1 1 1) //hex for main stroke outer ); //hex (1 0 0 6 4 3 3 8) (10 19 11) simpleGrading (1 1 1) Martini //hex (2 1 6 7 5 4 8 9) (20 19 11) simpleGrading (1 1 1) Martini edges ( arc 1 6 (0 0.489 0) arc 2 7 (0 4.89 0) arc 4 8 (0 0.489 1.55) arc 5 9 (0 4.89 1.55) arc 11 14 (0 0.489 17) arc 12 15 (0 4.89 17) arc 13 16 (0 6.985 17) arc 17 18 (0 6.985 1.55) ); patches ( wall liner ( (17 18 16 13) ) wall piston ( (0 1 6 0) (6 7 2 1) (2 7 9 5) (9 18 17 5) ) wall cylinderHead ( (10 14 11 10) (14 15 12 11) (15 16 13 12) ) cyclic cyclic ( (0 6 8 3) //positive, prism, bowl (6 7 9 8) //positive, hex, bowl (3 8 14 10) //positive, prism, main stroke (8 9 15 14) //positive, hex, main stroke inner (9 18 16 15) //positive, hex, main stroke outer (0 1 4 3) //negative, prism, bowl (1 2 5 4) //negative, hex, bowl (3 4 11 10) //negative, prism, main stroke (4 5 12 11) //negative, hex, main stroke inner (5 17 13 12) //negative, hex, main stroke outer ) empty center ( (0 3 3 0) (3 10 10 3) ) ); mergePatchPairs ( ); // * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * // boundary.org // * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * // 5 ( piston { type wall; physicalType fixedTemperatureMovingWallFunctions; nFaces 1083; startFace 288493; } liner { type wall; physicalType fixedTemperatureWallFunctions; nFaces 1957; startFace 286536; } cylinderHead { type wall; physicalType fixedTemperatureWallFunctions; nFaces 893; startFace 289576; } cyclic { type cyclic; physicalType cyclic; nFaces 10342; startFace 290469; featureCos 0.9; } center { type empty; physicalType empty; nFaces 0; startFace 300811; } ) engineGeometry // * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * // engineMesh layered; conRodLength conRodLength [ 0 1 0 0 0 0 0 ] 0.3048; bore bore [ 0 1 0 0 0 0 0 ] 0.1397; stroke stroke [ 0 1 0 0 0 0 0 ] 0.1524; clearance clearance [ 0 1 0 0 0 0 0 ] 0.002; rpm rpm [ 0 0 1 0 0 0 0 ] 1200; // ************************************************** *********** // 180/p // ************************************************** *********** // dimensions [1 1 2 0 0 0 0]; internalField uniform 233000; boundaryField { piston { type zeroGradient; } liner { type zeroGradient; } cylinderHead { type zeroGradient; } cyclic { type cyclic; } center { type empty; } } // ************************************************** *********** // controlDict: application dieselEngineFoam; startFrom startTime; startTime 180; stopAt endTime; endTime 180; deltaT 0.025; writeControl runTime; writeInterval 5; purgeWrite 0; writeFormat ascii; writePrecision 6; writeCompression uncompressed; timeFormat general; timePrecision 6; runTimeModifiable yes; adjustTimeStep yes; maxCo 0.2; maxDeltaT 1; 

December 18, 2011, 10:19 

#114 
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Carl
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Any clue?
Last edited by carl_xw4; December 18, 2011 at 10:41. Reason: I made a mistake! 

December 19, 2011, 07:16 

#115  
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Ayhan Eses
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Quote:
I am not a specialist but i tried to find out your problem. i use Code:
engineCompRatio Code:
ayhan@ayhan:~/paylasilan/uybh/carl$ engineCompRatio /**\  =========    \\ / F ield  OpenFOAM: The Open Source CFD Toolbox   \\ / O peration  Version: 2.0.1   \\ / A nd  Web: www.OpenFOAM.com   \\/ M anipulation   \**/ Build : 2.0.151f1de99a4bc Exec : engineCompRatio Date : Dec 19 2011 Time : 13:01:08 Host : ayhan PID : 2108 Case : /home/ayhan/paylasilan/uybh/carl nProcs : 1 sigFpe : Enabling floating point exception trapping (FOAM_SIGFPE). fileModificationChecking : Monitoring runtime modified files using timeStampMaster allowSystemOperations : Disallowing usersupplied system call operations // * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * // Create engine time Create mesh for time = 180 Selecting engineMesh layered deckHeight: 17 piston position: 1.55 CA = 0 deltaZ = 0.1524 clearance: 15.2976 Piston speed = 6.096 m/s Vmax = 310.486, Vmin = 307.567 Vmax/Vmin = 1.00949 End And another problem units. Your max. volume is Vmax = 310.486 m3, it should be Vmax = 0.000310486 m3 clearance: 15.2976 meter I think your geometry, shape, is ok. Maybe i am wrong. I think problem about blockMesh units. How could you build blockMesh? I really wonder which tool was used for blockmesh. I use Fluent mesh for engine geometry. I think you need a conversation factor or change the units of your software or rescale it. (meter>>milimeter). And for a motored case 180/p 233000 pa 2,33 bar, i think you should change this value with atmosferic pressure. Sorry my English is not well Best regards. Last edited by ayhan515; December 20, 2011 at 04:50. 

December 21, 2011, 10:47 

#116 
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Carl
Join Date: Dec 2011
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Hi
Thanks for your reply. I have actually converted the unit to meters. This is what I have generated with engineCompRatio: Create engine time Create mesh for time = 180 Selecting engineMesh layered deckHeight: 0.17 piston position: 0.0155 CA = 0 deltaZ = 0.1524 clearance: 0.0021 Piston speed = 6.096 m/s Vmax = 0.000310486, Vmin = 1.85732e05 Vmax/Vmin = 16.7169 I apologise if I didn't write my problem clearly. By the way, I managed to solve the problem. I actually stupidly included a not sensible mass flow rate in the fuel injection properties file. That causes the simulation to stop. Sorry! Best regards, Carl. 

January 30, 2012, 05:24 

#117  
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Hello Henry,
like Ramesh and Francesca I research documents to understand the bXi model but the links you gave a long time ago do not work. I also want to know about the reactants,products & burnt products in thermophysicalProperties file and how to determine these parameters for new fuel and oxydant. Could you send me some informations or documents about it? My email adress is: baptiste.lebrun@yahoo.fr Thanks a lot Baptiste Quote:
Quote:


September 30, 2014, 09:42 

#118  
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MultiComb
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Quote:
wen 

October 4, 2014, 10:42 

#119 
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Bruno Santos
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Quick answer: snapshots of the old abstract page can still be found at the Wayback Machine website: http://web.archive.org/web/200405120...abstracts.html
Then it's just a matter of looking for the paper by its title... 

August 11, 2015, 09:44 

#120 
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Join Date: Jul 2015
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hi kukikano,
I want to simulate an experimental case Bore*Stroke=76*66 by compression ratio equal to 21, what parameter I have to change?How can i fix compression ratio? For example, I want to run the blow case by the default mesh in kivaTest ,It's data in an article, Bore=86 mm Stroke=86 mm Compression ratio=14.04 Connection rod length=154.49 ***** My engineGoemetry is conRodLength conRodLength [ 0 1 0 0 0 0 0 ] 0.15449 bore bore [ 0 1 0 0 0 0 0 ] 0.086; stroke stroke [ 0 1 0 0 0 0 0 ] 0.086; clearance clearance [ 0 1 0 0 0 0 0 ] 0.02115; rpm rpm [ 0 0 1 0 0 0 0 ] 1500; ***** but i receive blow results CA = 0 deltaZ = 0.086 clearance: 0.000361 Piston speed = 4.3 m/s Vmax = 0.000631297, Vmin = 5.97945e05 Vmax/Vmin = 10.5578 ************* thanks in advance. kaveh Last edited by kaveh19; August 21, 2015 at 07:47. 

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