HOW TO USE CHEMKIN 경원테크

Agenda CHEMKIN-PRO vs. Old Chemkin II CHEMKIN-PRO Overview Advanced Feature: Particle Tracking Advanced Feature: Reaction Path Analysis Example : Turbulent jet with kinetics & mixing Example : Catalytic oxidation Example : Gas-turbine combustor modeled by Reactor Network Example : Multi-Zone Engine Model for piston engines 2

Who is Reaction Design? Software tool provider to the automotive, energy, and electronics markets since 1997 3

CHEMKIN-PRO vs. Old Chemkin II FEATURE Chemkin II CHEMKIN-PRO Combustion Reactor Surface Chemistry Automated Parameter Study Solver Speed Basic Enhanced Reaction Path Analyzer Particle Tracking Multi-Zone Engine Model Enhanced Reactor Networking Extinction Strain Rate Command Line Operation Graphical User Interface Tutorials Technical Support 4

CHEMKIN-PRO is Much Faster Simulation Speed-Up of CHEMKIN-PRO vs. CHEMKIN 5

Using CHEMKIN requires a chemistry set, reactor definition, and operating conditions Gas Chemistry ELEMENTS C H O N END SPECIES CH4 O2 H2O N2 CO2 H2 O H OH CO END REACTIONS H + H + M = H2 + M O + H2 = OH + H H + O2 = OH + O H + OH + M = H2O + M H2 + OH = H2O + H CO + O + M = CO2 + M Surface Chemistry Oxygen Methane Hydrogen Carbon Monoxide Hydroxyl Carbon Dioxide Water Geometry and Flow Conditions Transport Heat Transfer Diffusive and Convective Transport 7

Running CHEMKIN requires definition of a Chemistry Set, which consists of several files Thermodynamic database Must contain information for all species Transport database Must contain information for all gas-phase species Not required for many Reactor Models Gas chemistry reaction mechanism Identify elements and gas species in system Gas-phase reaction descriptions Surface chemistry reaction mechanism Define surface and bulk species Surface reaction descriptions 8

CHEMKIN is highly modular Gas Phase Chemistry / Thermodynamic Data Surface / Bulk Phase Chemistry / Thermodynamic Data Transport Properties Input GAS-PHASE KINETICS Utilities SURFACE KINETICS Utilities TRANSPORT Utilities Application Input CHEMKIN Application 9 Post-processing

Pre-processing of the chemistry set involves one to three steps Pre-processors create Linking Files that transfer chemistry-specific information to the Reactor Reactor Type Gas-phase Kinetics Thermodynamic Database Surface Kinetics Equilibrium ( 0-D Closed and PSRs ( Plug-flow PaSR Shock-tube Transport Properties Database Shear-layer Channel flow 1-D Flame Simulators CVD Reactors Mechanism Analyzer LPCVD Furnace LPCVD Thermal 10 Command-line Equivalents of Pre-processor commands chem i chem.inp d therm.dat -o chem.out surf -i surf.inp d therm.dat -o surf.out tran i tran.inp d tran.dat o tran.out

Example Gas-phase reaction mechanism (Gas-phase Kinetics Pre-processor input) 11 ELEMENTS H O N END SPECIES H2 H O2 O OH HO2 H2O2 H2O N N2 NO END REACTIONS H2+O2=2OH 0.170E+14 0.00 47780 OH+H2=H2O+H 0.117E+10 1.30 3626! D-L&W O+OH=O2+H 0.400E+15-0.50 0! JAM 1986 O+H2=OH+H 0.506E+05 2.67 6290! KLEMM,ET AL H+O2+M=HO2+M 0.361E+18-0.72 0! DIXON-LEWIS H2O/18.6/ H2/2.86/ N2/1.26/ OH+HO2=H2O+O2 0.750E+13 0.00 0! D-L H+HO2=2OH 0.140E+15 0.00 1073! D-L O+HO2=O2+OH 0.140E+14 0.00 1073! D-L 2OH=O+H2O 0.600E+09 1.30 0! COHEN-WEST. H+H+M=H2+M 0.100E+19-1.00 0! D-L H2O/0.0/ H2/0.0/ H+H+H2=H2+H2 0.920E+17-0.60 0 H+H+H2O=H2+H2O 0.600E+20-1.25 0 H+OH+M=H2O+M 0.160E+23-2.00 0! D-L H2O/5/ H+O+M=OH+M 0.620E+17-0.60 0! D-L H2O/5/ O+O+M=O2+M 0.189E+14 0.00-1788! NBS H+HO2=H2+O2 0.125E+14 0.00 0! D-L HO2+HO2=H2O2+O2 0.200E+13 0.00 0 H2O2+M=OH+OH+M 0.130E+18 0.00 45500 H2O2+H=HO2+H2 0.160E+13 0.00 3800 H2O2+OH=H2O+HO2 0.100E+14 0.00 1800 O+N2=NO+N 0.140E+15 0.00 75800 N+O2=NO+O 0.640E+10 1.00 6280 OH+N=NO+H 0.400E+14 0.00 0 END Reactions Rate Coefficients: A, B, E Species names must be consistent with thermo data H 2 /air Flame 3 elements 11 species 23 reactions

12 Data are coefficients of polynomial fits to temperature for species specific heats, enthalpy, and entropy Data is fixed format to match historical NASA equilibrium code Recent extensions allow more flexibility Thermo data also includes elemental composition of species Users may optionally include species thermodynamic data in the reaction-mechanism input files 7 4 5 3 4 2 3 2 1 0 6 4 5 3 4 2 3 2 1 0 4 5 3 4 2 3 2 1 0 4 3 2 ln 5 4 3 2 a T a T a T a T a T a R S T a T a T a T a T a a RT H T a T a T a T a a R c p Thermodynamic data is required for both gasphase and surface chemistry

Example of thermodynamic data input Symbolic species name Species composition Temperature limits for fit Break temp. for 2-part fit!! Species: AL2H6 CAS Number: 12004-30-7! Name: Aluminum Trihydride, Dimeric! Source: SNL fit to data generated from Pollard fit, 6/29/87! Comment: R. Pollard, J. Crystal Grow., V.77, P.200 (1986)! H0(298K) = 21.3500 (Kcal/mole), S0(298K) = 62.7500 (cal/mole-k) AL2H6 62987AL 2H 6 G 300.000 1500.000 600.00 1 2.63488400e+00 2.13595200e-02 3.15415100e-07-7.68467400e-09 2.33583200e-12 2 8.87134600e+03 9.82751500e+00-6.80068100e+00 5.08074400e-02 1.03974700e-05 3-1.11958200e-07 8.45915500e-11 1.06053700e+04 5.55452600e+01 4!! Species: AL2ME6 CAS Number: 15632-54-9! Name: Trimethylaluminum, Dimeric! Source: SNL fit to data generated from Pollard fit, 6/29/87! Comment: R. Pollard, J. Crystal Grow., V.77, P.200 (1986)! H0(298K) = -61.2000 (Kcal/mole), S0(298K) = 131.050 (cal/mole-k) AL2ME6 62987AL 2C 6H 18 G 300.000 1500.000 600.00 1 1.77314700e+01 4.93574700e-02 1.19685400e-06-1.63982600e-08 4.89086700e-12 2-3.85556000e+04-5.05329800e+01-7.15975000e-01 1.06710900e-01 2.11760500e-05 3-2.19321200e-07 1.64414400e-10-3.51554600e+04 3.89076300e+01 4 13 Comments provide more information about species Data for one species a 1 a 7 for 1 st fit range (high T)

Example of thermodynamic data input AL2H6 Thermodynamic Data Cp 0 H 0 S 0 14

Example entries in transport data file Species Name Linearity e/k s m a Z rot AR 0 136.500 3.330 0.000 0.000 0.000 AR* 0 136.500 3.330 0.000 0.000 0.000 C 0 71.400 3.298 0.000 0.000 0.000 C2 1 97.530 3.621 0.000 1.760 4.000 C2O 1 232.400 3.828 0.000 0.000 1.000 CN2 1 232.400 3.828 0.000 0.000 1.000 C2H 1 209.000 4.100 0.000 0.000 2.500 C2H2 1 209.000 4.100 0.000 0.000 2.500 C2H2OH 2 224.700 4.162 0.000 0.000 1.000 CH2OH 2 417.000 3.690 1.700 0.000 2.000 Lennard-Jones well depth Lennard-Jones polarizability diameter dipole moment rotational relaxation # 15

Example Surface Reaction Mechanism 16 SITE/SILICON/ SDEN/1.66E-9/ SI(S) END BULK SI(B)/2.33/ END THERMO ALL 300. 600. 1685. SI(S) J 3/67SI 100 000 000 0S 300.000 1685.000 1 0.24753989E 01 0.88112187E-03-0.20939481E-06 0.42757187E-11 0.16006564E-13 2-0.81255620E 03-0.12188747E 02 0.84197538E 00 0.83710416E-02-0.13077030E-04 3 0.97593603E-08-0.27279380E-11-0.52486288E 03-0.45272678E 01 4 SI(B) J 3/67SI 100 000 000 0S 300.000 1685.000 1 0.24753989E 01 0.88112187E-03-0.20939481E-06 0.42757187E-11 0.16006564E-13 2-0.81255620E 03-0.12188747E 02 0.84197538E 00 0.83710416E-02-0.13077030E-04 3 0.97593603E-08-0.27279380E-11-0.52486288E 03-0.45272678E 01 4 END REACTIONS SIH4 + SI(S) => SI(S) + SI(B) + 2H2 1.05E17 0.5 40000 SI2H6 + SI(S) => 2SI(S) + 2SI(B) + 3H2 4.55E26 0.5 40000 SIH2 + SI(S) => SI(S) + SI(B) + H2 3.9933E11 0.5 0.0 SI2H2 + 2SI(S) => 2SI(S) + 2SI(B) + H2 1.7299E20 0.5 0.0 2SI2H3 + 4SI(S) => 4SI(S) + 4SI(B) + 3H2 6.2219E37 0.5 0.0 H2SISIH2 + 2SI(S) => 2SI(S) + 2SI(B) + 2H2 1.7007E20 0.5 0.0 2SI2H5 + 4SI(S) => 4SI(S) + 4SI(B) + 5H2 6.1186E37 0.5 0.0 2SIH3 + 2SI(S) => 2SI(S) + 2SI(B) + 3H2 2.3659E20 0.5 0.0 2SIH + 2SI(S) => 2SI(S) + 2SI(B) + H2 2.4465E20 0.5 0.0 SI + SI(S) => SI(S) + SI(B) 4.1341E11 0.5 0.0 H3SISIH + 2SI(S) => 2SI(S) + 2SI(B) + 2H2 1.7007E20 0.5 0.0 SI2 + 2SI(S) => 2SI(S) + 2SI(B) 1.7607e20 0.5 0.0 SI3 + 3SI(S) => 3SI(S) + 3SI(B) 8.6586E28 0.5 0.0 END Thermodynamic data for surface species is usually included in Surface Kinetics input file (rather than therm.dat )

CHEMKIN: A set of tools designed to model complex chemical kinetic processes CHEMKIN Reactor Models represent idealized conditions Example: Cylindrical Shear-flow Reactor + 17

Reactor models represent different geometries and flow conditions Perfectly Stirred Reactor (PSR) (CSTR) Plug-flow Reactor (PFR) Partially Stirred Reactor T v Opposed-flow Diffusion Flame Pre-mixed Flame T v Shear-layer Channel-flow Reactor 18 Flame-speed Calculation

CHEMKIN-Pro Reactor Model 0-D reactor Closed Homogeneous Batch Reactor 1-D reactor Plug Flow Reactor(PFR) Closed Partially Stirred Reactor Closed Plasma Reactor Single zone HCCI Engine Multi zone HCCI Engine Plasma plug Flow Reactor Cylindrical Shear Flow Reactor Planar Shear Flow Reactor Honeycomb Monolith reactor Perfectly Stirred Reactor(PSR) Partially Stirred Reactor(PaSR) Plasma PSR 19

CHEMKIN-Pro Reactor Model Flame Simulation Premixed Laminar Burner-stabilized Flame Premixed Laminar Burner-stabilized Stagnation Flame Premixed Laminar Flame-speed Calculation Premixed Laminar Flame-speed Library Diffusion or Premixed Opposed-Flow Flame Extinction of Diffusion or Premixed Opposed-Flow Flame Shock Tube Reactors Normal Incident Shock Normal Reflected Shock CVD Reactor Stagnation Flow CVD Reactor Rotating Disk CVD Reactor LPCVD Reactor LPCVD Thermal Analyzer 20 LPCVD Furnace

Closed Reactors include homogeneous and mixing models Sensitivity 21 Internal Combustion Engine cylinder model Volume vs. time sweep Homogeneous mixture Compression ignition Generic Batch Reactor model Heat-transfer options Constrained volume or pressure Allows gas and surface chemistry Closed Plasma model Y k Electron energy equation Specified power-deposition Allows gas and surface chemistry Closed Partially Stirred Reactor Constrained volume or pressure Track mixing and kinetics time-scales R I Reaction #4 P time Reaction #18 Reaction #2 time

Open 0-D reactors provide basic flow elements and 1 st -order approximations 22 Generic Perfectly Stirred Reactor (PSR) Allows gas and surface chemistry Steady-state or transient mode Can be clustered Perfect Mixer No chemistry Steady-state or transient mode Can be clustered Open Plasma Reactor Allows gas and surface chemistry Electron energy and plasma power deposition Ion impact energy for surface chemistry Steady-state or transient mode Can be clustered Partially Stirred Reactor (PaSR) Turbulent-kinetics interactions

Clusters of open 0-D reactors allow mass and heat recycling to simulate complex flows Multiple inlet streams Different composition, Temperature, flow rate Recycle streams between reactors User-specified recycle fractions & paths Heat transfer between reactors Convection / conduction and/or radiation Perfectly stirred reactor elements R31 Inlet B Inlet C R13 Inlet A 1 2 3 Outlet 23 R11 R32

Flows where axial convection dominates can be modeled as plug-flow 24 Generic Plug-flow Reactor Reactor is assumed uniform in cross-flow direction Neglect diffusion Independent control of heat-loss and surface-chemistry areas Honeycomb Monolith Reactor Active surface area and hydraulic diameter determined from geometry Plasma Plug-flow Reactor Electron energy equation Power deposition over length of channel All include sensitivity analysis, heat-transfer options, and both gas-phase and surface chemistry Y k R Approximate as Surface Area per unit of distance I P Distance

Open 0-D and plug-flow reactor models have unique surface-chemistry capabilities Treatment of Multiple Materials 25 Use MATERIAL keyword in Surface Kinetics input file Specify separate chemistry on different materials Control relative surface areas of materials Modeling of Plasma/Surface Interactions Ion/electron recombination Ion-enhanced etching and etch yields Sensitivity analysis for Gas & Surface Chemistry Transient and steady-state Rate-of-production analysis Transient and steady-state Gas and surface reactions

Shear-layer Flow Reactors account for boundary-layer interactions Cylindrical Shear-flow Reactor Boundary-layer approximation of flow field in cylindrical coordinates Provides spatial variation in radial or transverse direction Includes radial diffusion Neglects axial diffusion o Axial convection dominates Variety of heat-transfer options Gas and surface chemistry Planar Shear-flow Reactor Boundary-layer approximation in planar coordinates 26

1-D Flame Models provide detailed flamestructure and balance transport and kinetics 27 Pre-mixed Burner Model Pre-mixed fuel and oxidizer Burner-stabilized flame Laminar flow Heat-of-formation and Reaction-rate sensitivity analysi Pre-mixed Flame-speed Calculator Predict adiabatic flame-speed Determine flammability limits and flame thickness Effects of heat loss and radiation transfer Laminar flow Heat-of-formation and Reaction-rate sensitivity analysi Opposed-flow Diffusion Flames Similarity transformation converts 2-D planar or 3-D axisymmetric into 1-D model 1-D boundary conditions assumed Diffusion-flame flammability limits Flamelet model for generating CFD look-up tables Heat-of-formation and Reaction-rate sensitivity analysis

CHEMKIN s normal-shock models can be used to simulate shock-tube experiments Incident Shock Model Users specify conditions before the shock wave Gas-dynamic relations determine initial post-shock conditions Transient kinetics after shock has passed Viscosity effects can be included Reflected Shock Model Gas-dynamic relations determine conditions after reflected shock Transient kinetics start after reflected shock passes Incident Shock U 2 2 1 Reflected Shock U s U 2 5 2 U rs 28

Particle Tracking in CHEMKIN-PRO Get fast and accurate answer to what if questions - Predict particle properties, mass emission and size distribution - Wide range of reactor models to fit your application 30 Use accurate gas-phase and surface chemistry - Nucleation - Agglomeration - Surface growth Two options depending on the answer you need - Method of Moments model : Average size, total mass emissions - Sectional model: Adds information on particle size distribution

Example: Soot in a Jet-Stirred Reactor(JSR) JSR/PFR system developed at MIT (Marr, 1993) Chemistry: - Gas-phase: Ethylene/Air (includes formation of PAH precursors) - Surface mechanism includes nucleation, oxidation and pyrene and PAH condensation reactions - Use Method of Moments for average diameter and number density 31

Example: Soot in a Jet-Stirred Reactor(JSR) 1630K, Φ=2.2 Case of the C2H2/O2/N2 Soot Mass Concentration Particle Diameter Evolution 32

Example: Premixed Stagnation Flame Premixed ethylene/air flame impinging on a wall - Gas-phase: Ethylene/Air (includes formation of PAH precursors) Sectional method for size distribution information - Size coordinate (D) is divided into sectional bins 33

Reaction Path Analysis in CHEMKIN-PRO Identification of dominant pathways Determination of pathways contributing to pollutant formation Determination of changes in pathways due to variation of operating conditions Guiding of mechanism reduction efforts 35

Reaction Path Analysis in CHEMKIN-PRO Reaction path diagram start : CH4 Control of reaction path Species sensitivity start End The number of species Species : rate of production Color : species (red : OH) Dynamic selection of location in solution 36

Reaction Path Analysis in CHEMKIN-PRO Rate of production for a path 37 Rate of progress

In many real systems, e.g. turbulent jets, perfect mixing cannot be assumed Gas turbines* Mixing zone with pre-mixed fuel and re-circulated burned products» ignition time delay Flame zone Post-flame zone with cool air addition Industrial burners Jet entrance region Internal combustion engines Effect of residual gas trapped on ignition time delay 39 *Ref: S.M. Correa, Combustion and Flame 93:41-60 (1993). J.-Y. Chen, Combustion Science and Technology 122:63-94 (1997)

The Partially Stirred Reactor (PaSR) addresses turbulence-kinetics interactions Considers effects of mixing on the kinetics of a combusting system Uses Monte Carlo mixing method Allows detailed kinetics Explores effects of mixing time scale, relative to the reactor residence time, mix res 40

PaSR is a computationally efficient means for considering chemistry and mixing Sequential Monte Carlo Simulation of Probability Density Functions for Species*: ~ ~ P t t I tc tm tk P t O t Identity Operator Chemical Reaction Molecular Mixing Convection t 41 *Ref: S.B. Pope, Combustion Science and Technology 25:159-174 (1981)

The partially stirred reactor model tracks turbulent mixing and reaction in a zone Consider two reacting streams: Inlet 1 = 100% A Reaction A + B C Inlet 2 = 100% B Mixing and Reaction Zone Time t = 0 42

PaSR considers convection, molecular mixing, and kinetics in each time step Convection Molecular Mixing Chemical Reaction Time t = t 43 Kinetics options: No reactions Equilibrium calculation Full finite-rate CHEMKIN kinetics Molecular Mixing options : Modified Curl s Model Interaction by Exchange with Mean (S. Correa) Reaction A + B C

Input required to define a PaSR Residence time of the mixing zone (based on flow rate) Characteristic Mixing time mix k e Estimate based on flow (e.g. CFD calculation) Range ~ ms to s Chemical reaction mechanism Gas-phase Kinetics Input file Thermodynamic data 44

The PaSR input, Mixing Timescale, is a characteristic of the turbulent flow field May be determined from a CFD calculation CFD flow simulation provides k, epsilon Small values make a PaSR behave like a perfectly stirred reactor (PSR) mix k e Large values make a PaSR behave like a plug flow reactor (PFR) mix res mix res 45

Comparison of two mixing models Modified Curl s Model Interaction by Exchange w/ Mean 46

Example: Turbulent mixing and kinetics for H 2 fuel and air Consider a jet of H2 into hot air How does mixing affect ignition? Air Air Air H 2 Reaction and mixing Reaction and mixing time 47

Example: Turbulent mixing and kinetics for H 2 fuel and air Jet conditions General o Pressure = 1 atm o Simulation time = 5 msec Air Entrainment o Flow rate = 1 g/s o Temperature = 1500 K Initial conditions of jet o Pure H 2 fuel o Temperature = 300 K Characteristic times o Residence = 1.E-3 sec o Mixing = 1.E-4, 1.E-5, or 1.E-6 sec Air H 2 Air Reaction and mixing Model options Include chemistry Use Curl s mixing model» Factor = 1 Solution method» Backwards differencing Monte Carlo options» Number of particles (number of statistical events) = 400» Time step = 1.E-5 sec Air Reaction and mixing 48

Example: Turbulent mixing and kinetics for H 2 fuel and air Results show effects of mixing on ignition Temperature Mean values OH 49

Example: Turbulent mixing and kinetics for H 2 fuel and air PaSR saves a probability distribution function (pdf) at the end of the run for a specified variable pdf.plt file The file can be imported into the Graphical Postprocessor and plotted MIXT / TAU = 0.001 50

Characteristics of Catalytic Oxidation Compared to homogeneous combustion: 1. Flameless process even though heat is released Less sooting 2. Generally proceeds at lower temperatures 3. Lower emissions of NO x are typical 4. Combustion occurs over a wider range of fuel/air ratios (c.f. CH 4 5-15%) Stability / robustness of process 5. Facilitates flexibility in burner designs 52

Example: Catalytic Oxidation in Turbines The Challenge: Improve efficiency and reduce pollutant emissions (NO x ) Main Fuel Pre-burn Fuel Catalyst Monolith Exhaust Compressor Stage Turbine Stage Main features of GE and Allison Systems Designs 53

Simulation requires detailed surface chemistry and flow model of monolith Surface Chemistry Reaction Mechanism Oxygen Methane Hydrogen Carbon Monoxide Carbon Dioxide Hydroxyl Water Geometry and Fluid Flow Surface Reactions Gas Phase Reactions Heat Transfer Diffusive and Convective Transport 54 Ref: L. L. Raja, R. J. Kee, O. Deutschmann, J. Warnatz, L. D. Schmidt, Catalysis Today, 59 (2000) 47-60

Example: Catalytic oxidation of CH 4 on Pt with Shear-layer Flow Shear-layer flow includes surface kinetics and boundarylayer effects (PFR won t do) Example: Pre-burn catalytic oxidation component in gas turbine CH 4 oxidation on Pt Neglect gas-phase chemistry 55

Example: Catalytic oxidation of CH 4 on Pt with Shear-layer Flow Monolith Tube 3% CH 4 in air u = 5 m/s T = 770 K P = 1 atm. Pt Catalyst 20 cm Adiabatic Q=0 1 mm Model a single channel in the monolith Surface mechanism includes 8 gas-phase species 11 surface site species 22 surface reactions 56

Example: Catalytic oxidation of CH 4 on Pt with Shear-layer Flow Is there a flame? How far down the channel does light-off occur? What is the optimal channel length for converting CH 4 to CO 2 On what parameters will this depend? What would you expect the effect of adding gas chemistry to be? Would NO x production be high? 57

Example: Catalytic oxidation of CH 4 on Pt with Shear-layer Flow Results show a lot happening at around 11-12 cm along the channel 58 Simulation is axisymmetric

Example: Catalytic oxidation of CH 4 on Pt with Shear-layer Flow Conversion appears to be complete! 59

Example: Catalytic oxidation of CH 4 on Pt with Shear-layer Flow Velocity profiles fully developed at ~ 4 cm Velocity Profiles at beginning of Channel Distance Along Channel 60

Example: Catalytic oxidation of CH 4 on Pt with Shear-layer Flow The surface self-heats due to the surface oxidation kinetics At ~ 10 cm, the reaction takes off, T goes to 1485 K No flame the wall is always the hottest point 61

Example: Catalytic oxidation of CH 4 on Pt with Shear-layer Flow The gas equilibrates quickly with the wall due to the thinness of the channel Aspect ratio is 200:1 62 Centerline Wall

Example: Catalytic oxidation of CH 4 on Pt with Shear-layer Flow Surface profiles show light-off behavior Surface site coverage critical to catalyst behavior Exothermal Reaction Kicks In 63

A gas turbine combustor may be modeled as a PSR network with a PFR at the end. Air Air Premixed Fuel + Air Fuel + Air Air Mixing Zone Recirc. Zone Post-Flame Zone 65 Air Flame Zone perfectly-stirred reactors plug-flow reactor

Example: Gas-turbine combustor with reactor network 1 2 3 Results from 3 PSR Network 4 O 2 CH 4 H 2 O CO 2 66

Using PFR for post-flame provides more accurate prediction of emissions Temperature NO Fraction Radical Species O OH CO H PFR Results 67

68 Accurate Reactor Networks are Complex

Multi-zone Engine Model Zone Definition 70

Multi-zone Engine Model Results 71