
[Sponsors] 
Premixed heptaneair combustion in a diesel engine (HCCIdieselEngineFoam) 

LinkBack  Thread Tools  Display Modes 
November 25, 2011, 11:23 
Premixed heptaneair combustion in a diesel engine (HCCIdieselEngineFoam)

#1 
Member
Ayhan Eses
Join Date: Mar 2009
Posts: 34
Rep Power: 8 
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 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 

August 19, 2015, 10:01 

#2 
Member
Join Date: Jul 2015
Posts: 31
Rep Power: 2 
hi ayhan515,
I want to run a HCCI,my thesis topic, engine .I can't fix my favorite compression .In fact I don't know how specify Vmin(clearance volume) and Vmax. please help me out. 

August 21, 2015, 07:44 

#3 
Member
Join Date: Jul 2015
Posts: 31
Rep Power: 2 
Hi ayhan515,
Changing your mesh size maybe can help you. 

Thread Tools  
Display Modes  


Similar Threads  
Thread  Thread Starter  Forum  Replies  Last Post 
Diesel Engine combustion chamber analysis  sachinthakre  FLUENT  12  August 13, 2013 14:14 
CFD of combustion process of Homogeneous Charge Compression Engine (HCCI)  kelvinlim  Main CFD Forum  2  January 26, 2012 23:19 
Diesel Engine Combustion Analysis  fluidsuser  FLUENT  0  December 1, 2010 22:29 
air bubble is disappear increasing time using vof  xujjun  CFX  9  June 9, 2009 07:59 
diesel engine spray and combustion  usker  CDadapco  6  April 24, 2006 22:36 