internal combustion engines - princeton university...q a i d i aa t b gas soot π πσ = = − ∝+...

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Copyright ©2018 by Rolf D. Reitz. This material is not to be sold, reproduced or distributed without prior written permission of the owner, Rolf D. Reitz. 1 PCI-3-7, 2018 Internal Combustion Engines I: Fundamentals and Performance Metrics Prof. Rolf D. Reitz, Engine Research Center, University of Wisconsin-Madison 2018 Princeton-Combustion Institute Summer School on Combustion Course Length: 9 hrs (Mon.- Wed., June 25-27) Hour 7: Heat transfer and Spray Combustion Research

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  • Copyright ©2018 by Rolf D. Reitz. This material is not to be sold, reproduced or distributed without prior written permission of the owner, Rolf D. Reitz.

    1 PCI-3-7, 2018

    Internal Combustion Engines I: Fundamentals and Performance Metrics

    Prof. Rolf D. Reitz,

    Engine Research Center, University of Wisconsin-Madison

    2018 Princeton-Combustion Institute Summer School on Combustion

    Course Length: 9 hrs (Mon.- Wed., June 25-27)

    Hour 7: Heat transfer and Spray Combustion Research

  • 2 PCI-3-7, 2018

    Hour 7: Heat transfer and Spray Combustion Research

    Short course outline:

    Internal Combustion (IC) engine fundamentals and performance metrics, computer modeling supported by in-depth understanding of fundamental engine processes and detailed experiments in engine design optimization.

    Day 1 (Engine fundamentals)

    Hour 1: IC Engine Review, Thermodynamics and 0-D modeling Hour 2: 1-D modeling, Charge Preparation Hour 3: Engine Performance Metrics, 3-D flow modeling

    Day 2 (Computer modeling/engine processes)

    Hour 4: Engine combustion physics and chemistry Hour 5: Premixed Charge Spark-ignited engines Hour 6: Spray modeling

    Day 3 (Engine Applications and Optimization) Hour 7: Heat transfer and Spray Combustion Research Hour 8: Diesel Combustion modeling Hour 9: Optimization and Low Temperature Combustion

  • Scorching Detonation Cracking

    Engine heat transfer

    Up to 30% of the fuel energy is lost to wall heat transfer Can influence engine ignition/knock Engine durability – catastrophic engine failure

    Challen, 1998

    3 PCI-3-7, 2018

    Hour 7: Heat transfer and Spray Combustion Research

  • Heat transfer

    ( ) ( ) c s rI I p Q Q Qtρ

    ρ ρε∂

    +∇ = − ∇ −∇ + + + +∂

    u u J

    Gas phase energy equation

    Radiation source term

    ( ) ( ) ( )4

    , 4r bQ I d Iπ

    κ π=

    = −

    Ω

    r r Ω Ω r

    ( ) ( )( )

    * *ln 2.1 33.34

    2.1ln 2.5g p g g w

    w

    C u T T T y G uq

    y

    ρ υ+

    +

    − +=

    +

    ( )( )

    * ln

    2.1ln 2.5p g g w

    w

    C u T T Tq

    y

    ρ+

    =+

    2.1 2.1wg p

    qdT Gdy C yρ ν

    ++

    = +

    ( )2.1 * ln

    2.1ln 2.5

    gg

    w

    Tu T TdTdy y yυ + +

    =

    +

    Wall heat flux (account for compressibility) With radiation Without radiation

    G radiative heat flux = qwr

    Han, 1995 Wang, 2012

    4 PCI-3-7, 2018

    wall

    ∆y

    qw * /y y u ν+ = ∆ u*

    Hour 7: Heat transfer and Spray Combustion Research

  • Radiative heat transfer • Radiation Transfer Equation (RTE):

    • Discrete Ordinates Method (DOM)

    Absorption & out-scattering

    Blackbody emission

    In-scattering

    Direction Number m

    Ordinates Weights wm ξm ηm μm

    1 0.4719707 0.2158271 0.8547879 0.2617994

    2 0.2158271 0.4719707 0.8547879 0.2617994

    3 0.2158271 0.8547879 0.4719707 0.2617994

    4 0.4719707 0.8547879 0.2158271 0.2617994

    5 0.8547879 0.4719707 0.2158271 0.2617994

    6 0.8547879 0.2158271 0.4719707 0.2617994

    Hour 7: Heat transfer and Spray Combustion Research

    5 PCI-3-7, 2018

    Wiedenhoefer, 2003

  • Soot and gas absorption Total absorption coefficient Soot absorption Wide band model for CO2 and H2O

    2 2net soot CO H Oa a a += +

    -11260 msoot soota C T= CO2 absorption bands

    ( )2

    31

    2,1b band center C T band center

    CTeη η

    ηε η

    = −

    ( ) ( )1, , ln 1 , ,g e g ee

    a T P L T P LL

    ε = −

    ( )( )( )( )2 21 1 1 1 1fuel CO CO H Oε ε ε ε ε= − − − − −

    Importance of soot:

    1gasa T

    ∝ soota T∝

    ( ) ( ) ( ) 44

    , 4r b gas sootQ a I d I a a Tπ

    π σ=

    = − ∝ +

    Ω

    r r Ω Ω r 3 5gas sootT Tσ ∝ +

    6 PCI-3-7, 2018

    Hour 7: Heat transfer and Spray Combustion Research

    Wiedenhoefer, 2003a

  • Radiative heat transfer • Radiative property of absorbing gas (CO2, H2O, CO)

    • Radiative property of soot:

    • Total absorption coefficient:

    Narrow-band model (RADCAL)

    Planck-mean absorption coefficient:

    1000 1500 2000 25000.0

    0.1

    0.2

    0.3

    0.4

    Narrowband Model

    ab

    sorp

    tion

    coef

    ficie

    nt (a

    tm c

    m)-1

    CO2 H2O CO

    Temperature (K)Absorption coefficients as function of temperature

    Yoshikawa, 2009

    Hour 7: Heat transfer and Spray Combustion Research

    7 PCI-3-7, 2018

  • Wall heat transfer Conjugate heat transfer modeling ERC - Heat Conduction in Components code (HCC)

    Iterative coupling between HCC and CFD code

    Unstructured HCC Mesh

    Wiedenhoefer, 2000

    8 PCI-3-7, 2018

    Hour 7: Heat transfer and Spray Combustion Research

  • 9 PCI-3-7, 2018

    Wall heat transfer

    Cut Plane

    Cummins N14 engine

    . . . . . . . . .

    Caterpillar SCOTE engine

    Wiedenhoefer, 2000

    Hour 7: Heat transfer and Spray Combustion Research

  • -20 -15 -10 -5 0

    560

    580

    600

    620

    640

    660

    680

    700

    720

    740No Radiation

    Run 1 Run 2 Run 3

    With Radiation Run 1 Run 2 Run 3

    Peak

    Pist

    on T

    empe

    ratu

    re [K

    ]

    Start of Injection, ATDC

    Φ = 0.7

    Predicted piston temperature - CDC

    Effect of radiation on wall heat loss Total heat loss increased by 30% due to radiation. 34% - head, 19% - liner, 47% - piston. Lowers bulk gas temperatures Results in lower NOx and higher soot NOx reduced by as much as 30% (ave)

    -20 -15 -10 -5 0

    2

    4

    6

    8

    10

    12

    14

    16

    NOx

    [g/k

    Wh]

    Start-of-injection, ATDC

    Φ = 0.5 Uniform Temp / No rad Non-uniform Temp / With Rad

    Φ = 0.7 Uniform Temp / No rad Non-uniform Temp / With Rad

    Wiedenhoefer, 2003

    10 PCI-3-7, 2018

    Hour 7: Heat transfer and Spray Combustion Research

  • Diesel and other fuels; Constant volume chamber; various temperatures; Varying chamber densities: 13.9, 28.6, 58.6kg/m3. Schlieren imaging

    Spray Combustion Research Naber, 1996

    Pickett, Sandia National Laboratory, "Engine Combustion Network", https://share.sandia.gov/ecn/

    Siebers, 1998

    11 PCI-3-7, 2018

    Hour 7: Heat transfer and Spray Combustion Research

    Liquid Penetration Length

    0 1 2 30

    20

    40

    60

    80

    100

    Liquid

    Pene

    tratio

    n (m

    m)

    time ASI [ms]

    Experiment CFD

    Tamb=900Kρamb=22.8 kg/m

    3

    Pinj=150 MPa

    Vapor

    Wang, 2014

    https://share.sandia.gov/ecn/

  • Diesel combustion (Conceptual model of Dec, 1997) Time to mix fuel/air to “combustible” ratios Time at given T and P to initiate combustion

    Dec, 1997

    12 PCI-3-7, 2018

    Hour 7: Heat transfer and Spray Combustion Research

  • Diesel combustion regimes

    Conventional Diesel

    Dec used optical diagnostics to develop a conceptual model of conventional diesel combustion

    OH exists only at periphery of the jet thin diffusion flame surrounding a soot filled jet

    LTC diesel Combustion

    Musculus developed a similar conceptual model for diesel LTC

    Low temperature reactions fill the head of the jet with intermediates (e.g., CH2O) OH is observed across the entire jet cross-section

    Dec’s conceptual model LTC conceptual model

    Dec, 1997

    Musculus 2006

    13 PCI-3-7, 2018

    Hour 7: Heat transfer and Spray Combustion Research

  • Soot Modeling

    Soot models

    Two-step model Multi-step

    Phenomenological (MSP) model

    PAH chemistry

    Patterson, SAE 940523 Kong, ASME 2007 Vishwanathan & Reitz, SAE 2008-01-1331 Vishwanathan & Reitz, 2009

    Kazakov & Foster, SAE 982463 Tao, 2009 Tao, SAE 2006-01-0196 Tao, 2006 Vishwanathan & Reitz, SAE 2008-

    01-1331

    Vishwanathan & Reitz, CST 2010

    Models of soot formation/oxidation – Kennedy, Prog. Energy Comb. Sc., 1997 Soot processes in engines - Tree and Svenson, Prog. Energy Comb. Sc., V2007

    14 PCI-3-7, 2018

    Hour 7: Heat transfer and Spray Combustion Research

  • ssf so

    d(M ) =M -Mdt

    0.5sf sf sf C2H2M =A P exp(-E /RT) M⋅ ⋅ ⋅

    so nsc ss nom

    6M = W Mρ D

    ⋅ ⋅

    Two-step model

    Hiroyasu soot formation

    Nagle and Strickland-Constable (NSC)

    oxidation

    Net soot mass

    C2H2 soot precursor

    ρs = Soot density = 2 g/cm3

    Dnom = assumed nominal soot diameter

    = 25 nm

    Wnsc = NSC oxidation rate/area

    Mc2h2 = C2H2 Mass, Ms = Mass of soot

    “tuning” const

    Hiroyasu & Kadota, SAE 760129 Nagle & Strickland-Constable, 1962

    15 PCI-3-7, 2018

    Hour 7: Heat transfer and Spray Combustion Research

  • SANDIA spray chamber:

    Vishwanathan, 2008

    C2H2 inception occurs at lift-off location

    Inclusion of PAH chemistry needed for accurate prediction of soot form/oxid.

    Soot mass comparison

    0

    0.5

    1

    1.5

    2

    0 20 40 60 80 100 120Distance from Injector (mm)

    Soot

    Mas

    s (m

    icro

    gm

    s)

    Expt.Model

    Model predicted soot inception location → Lift-off length position

    Performance of two-step soot model

    Pickett, 2004

    16 PCI-3-7, 2018

    Hour 7: Heat transfer and Spray Combustion Research

  • Heptane injection

    C2H2 inception occurs at lift-off location

    Inclusion of PAH chemistry needed for accurate prediction of soot form/oxid.

    Performance of two-step soot model

    Sandia experiment

    Model

    Pickett, 2004

    17 PCI-3-7, 2018

    Hour 7: Heat transfer and Spray Combustion Research

    Vishwanathan, 2008

  • 18 PCI-3-7, 2018

    Phenomenological soot models

    Hour 7: Heat transfer and Spray Combustion Research

    Tao, 2006

  • Reduced PAH mechanism Reduced PAH mechanism of Xi & Zhong, 2006 based on detailed mechanism of Wang &Frenklach, 1997 was integrated (20 species and 52 reactions) A1 formation through propargyl radical (C3H3) Higher aromatics formed through HACA scheme (hydrogen abstraction, carbon addition)

    Reaction Arrhenius parameters-A, n, E. (Units of A in mole-cm-sec-K and units of E in cal/mole)

    C3H3 + C3H3 → A1 2.0E+12, 0.0, 0.0 A1- + C4H4 ↔ A2 + H 2.50E+29, -4.4, 26400.0

    A1+ A1-↔ P2 + H 1.10E+23, -2.9, 15890.0 A2-1 + C4H4 ↔ A3 + H 2.50E+29, -4.4, 26400.0 A1C2H* + A1 ↔ A3 + H 1.10E+23, -2.9, 15890.0 A3-4 + C2H2↔ A4 + H 3.00E+26, -3.6, 22700.0

    A1 = benzene, A2 = naphthalene, P2 = biphenyl, A3 = phenanthrene, A4= pyrene, A1- = phenyl, A2-1 = 1-naphthyl, A3-4 = 4-phenanthryl, A1C2H* = phenylacetylene radical

    Vishwanathan, 2009

    19 PCI-3-7, 2018

    Hour 7: Heat transfer and Spray Combustion Research

  • Amount of dry-carbon mass locked-up in aromatic precursors small compared to measured soot

    PAH species

    0 20 40 60 80 1001E-5

    1E-4

    1E-3

    0.01

    0.1

    1Expt. soot mass

    A4

    A3

    A2

    A1

    C2H2

    Soot

    /Car

    bon

    mas

    s in

    pre

    curs

    ors

    (µg)

    Distance from Injector (mm.)

    15% O2

    15% O2, A3 is precursor

    Expt.

    CFD

    Improvement in soot location

    Reduced PAH mechanism implemented considering up to 4 aromatic rings (pyrene) - A3 (Phenanthrene) used as precursor for soot formation model

    ~ peak of 0.016 ppm

    Sandia expts: Pickett & Idicheria, 2006

    20 PCI-3-7, 2018

    Hour 7: Heat transfer and Spray Combustion Research

    Vishwanathan, 2009

  • Soot model implementation

    1. Soot inception through A4:

    2. C2H2 assisted surface growth:

    3. Soot coagulation:

    1 1 1ω-1= k [A ], k = 2000 {s }4⋅

    2 2 2 2 2

    p

    ω { }

    N { }p

    {

    4 -1= k [C H ], k = 9.0 10 exp(-12100/T) S s 2 -1S = πd cm

    1/36Y ρc(s)d = cm}πρ Nc(s)

    ⋅ ⋅ ⋅

    Surface area per unit volume

    Particle size

    Graphitization

    YC(S) = soot mass fraction

    N = soot number density (per cc)

    ρC(S) = 2.0 gm/cm3

    MC(S) = MW of carbon

    Kbc = Boltzmann’s constant

    Ca = agglomeration constant = 9

    1ωC H (A ) 16C(s) + 5H 16 10 4 2→

    3ωnC(s) C(s)n→

    3

    1/6 1/26M ρY6K Tc(s) c(s) 1/6 11/6 -3 -1bcω = 2C [ ] [N] {particles cm s }a πρ ρ Mc(s) c(s) c(s)

    ⋅ ⋅ ⋅

    Mono –disperse locally: All soot in a comp. cell have same diameter

    Vishwanathan, 2010

    Leung, 1991

    Leung, 1991

    21 PCI-3-7, 2018

    Hour 7: Heat transfer and Spray Combustion Research

  • 4. O2 assisted soot oxidation (NSC model):

    5. OH assisted oxidation (Modified Fenimore and Jones model):

    4c(s)

    K PA O12 -3 -12ω = x+K P (1-x) S {mol cm s }B OM 1+K P 2Z O2

    ⋅ ⋅ ⋅ ⋅

    x = P (P + (K /K ))T BO O2 2-2 -1 -1K = 30.0 exp (-15800/T) {g cm s atm }A

    -3 -2 -1 -1K = 8.0 10 exp (-7640/T) {g cm s atm }B5 -2 -1K = 1.51 10 exp (-49800/T) {g cm s }T

    -1K = 27.0 exp (3000/T) {atm }Z

    ⋅ ⋅

    ⋅ ⋅

    x = fraction of A sites

    (1-x) = fraction of B sites

    PO2 = partial pressure of O2 KA,B,T,Z = rate constants

    XOH = mole fraction of OH

    γOH = OH collision efficiency = 0.13

    Soot model implementation

    Fenimore, 1967

    22 PCI-3-7, 2018

    Hour 7: Heat transfer and Spray Combustion Research

    Vishwanathan, 2010

  • 6. PAH-assisted surface-growth

    k = number of carbon atoms and j = number of hydrogen atoms,

    γks = 0.3 is the collision efficiency between soot and PAH, βks = collision frequency,

    di = collisional diameter of PAH, dA = size of single aromatic ring = 1.393√3 Ǻ,

    μi,j = Reduced mass of colliding species = Mass of PAH,

    mi = mass of PAH expressed in terms of number of carbon atoms - k

    Most models consider only mono-aromatic benzene as growth species.

    { }2 3 -1bcks p PAHi,j

    π K Tβ = 2.2 (d + d ) cm s2 μ⋅ ⋅

    ⋅ ⋅⋅

    iPAH A

    2md = d3

    Soot model implementation

    23 PCI-3-7, 2018

    Hour 7: Heat transfer and Spray Combustion Research

    Vishwanathan, 2010

  • 7. Transport equations:

    M = ρYc(s) (soot species density) and N (number density) with N being treated

    as passive species Thermophoresis term implemented as a source term

    dnuci = 1.25 nm (~100 carbon atoms)

    πηξ= 0.75 (1+ ) , η = 0.98

    M 1 3

    Mc(s) -3 -1S = 16ω - ω {particles cm s } for NMnuci

    π 3 M = d ρ nuci nuci c(s)6

    ⋅ ⋅

    Thermophoresis Source terms diffusion convection

    Soot model implementation

    24 PCI-3-7, 2018

    Hour 7: Heat transfer and Spray Combustion Research

    Vishwanathan, 2010

  • ECN Spray A modeling

    25 PCI-3-7, 2018

    Temp [K] 800 850 900 1000 1100 1200 O2 [vol%] 15 13/15/17/21 13/15/17/21 13/15/17/21 13/15/17/21 13/15/17/21 Density [kg/m3] 22.8

    7.6/15.2/ 22.8/30.4

    7.6/15.2/ 22.8/30.4

    7.6/15.2/ 22.8/30.4

    7.6/15.2/ 22.8/30.4

    7.6/15.2/ 22.8/30.4

    Pinj [MPa] 150 50/100/150 50/100/150 50/100/150 50/100/150 50/100/150

    Computational grid Related sub-models

    Lift-off length Onset of the averaged OH concentration Ignition delay Maxmium dT/dt Maxmium dOH/dt

    Phenomenon Model

    Spray breakup KH-RT instability Evaporation Discrete multicomponent (DMC) Turbulence Generalized RNG k−ε model Combustion SpeedChem Droplet collision ROI model Near nozzle flow Gas-jet model Soot formation Multi-step phenomenological

    Wang, 2014

    Hour 7: Heat transfer and Spray Combustion Research

  • ECN Spray A modeling

    26 PCI-3-7, 2018

    Non-reacting mixing process

    0 1 2 3 4 50

    5

    10

    15

    20

    25

    30

    Liqu

    id P

    enet

    ratio

    n [m

    m]

    Time ASI [ms]

    Expt. Simulation

    ECN Spray-An-C12 non-reactingTamb=900K

    Density=22.8kg/m3

    Inj Dur=6.0 ms

    0 1 2 3 40

    20

    40

    60

    80

    100

    Vap

    or P

    enet

    ratio

    n [m

    m]

    Time ASI [ms]

    Expt. Simulation

    ECN Spray-An-C12 non-reactingTamb=900K

    Density=22.8kg/m3

    Inj Dur=6.0 ms

    Ambient conditions

    O2 0.0

    N2 0.8971

    CO2 0.0652

    H2O 0.0377

    Pressure 60.45 bar

    Temperature 900 K

    Density 22.8 kg/m3

    Injector specifications

    Type Common-rail

    Nozzle Single-hole, 0.89

    Nozzle diameter 0.084 mm (0.090mm)

    Injection pressure 150 MPa

    Injection duration 6.0 ms

    Injection fuel mass 13.77 mg

    Liquid and vapor penetrations1

    1. Engine Combustion Network, http://www.sandia.gov/ecn/

    Wang, 2014

    Hour 7: Heat transfer and Spray Combustion Research

    http://www.sandia.gov/ecn/

  • ECN Spray A modeling

    27 PCI-3-7, 2018

    0.0 1.5 3.0 4.5 6.00.00

    0.04

    0.08

    0.12

    0.16

    0.20ECN Spray-An-C12 non-reactingTamb=900K

    Density=22.8kg/m3

    Inj Dur=6.0 ms

    Mix

    ture

    Fra

    ctio

    n [-

    ]

    Radial distance [mm]

    Expt. Simulation

    Z=20mm

    0 2 4 6 80.00

    0.03

    0.06

    0.09

    0.12

    0.15 ECN Spray-An-C12 non-reactingTamb=900K

    Density=22.8kg/m3

    Inj Dur=6.0 ms

    Mix

    ture

    Fra

    ctio

    n [-

    ]

    Radial distance [mm]

    Expt. Simulation

    Z=30mm

    0.0 2.5 5.0 7.5 10.00.00

    0.03

    0.06

    0.09

    0.12

    0.15ECN Spray-An-C12 non-reactingTamb=900K

    Density=22.8kg/m3

    Inj Dur=6.0 ms

    Mix

    ture

    Fra

    ctio

    n [-

    ]

    Radial distance [mm]

    Expt. Simulation

    Z=40mm

    0.0 2.5 5.0 7.5 10.0 12.50.00

    0.02

    0.04

    0.06

    0.08

    0.10 ECN Spray-An-C12 non-reactingTamb=900K

    Density=22.8kg/m3

    Inj Dur=6.0 ms

    Mix

    ture

    Fra

    ctio

    n [-

    ]

    Radial distance [mm]

    Expt. Simulation

    Z=50mm

    20 25 30 35 40 45 50 55

    0.05

    0.10

    0.15

    0.20

    0.25ECN Spray-An-C12 non-reactingTamb=900K

    Density=22.8kg/m3

    Inj Dur=6.0 ms

    Mix

    ture

    Fra

    ctio

    n [-

    ]

    Axial distance [mm]

    Expt. Simulation

    Axial

    Non-reacting mixing process - Fuel mixture fraction

    1. Engine Combustion Network, http://www.sandia.gov/ecn/

    Predicted mixture fraction distributions agree reasonable well with experimental data in both radial and axial directions by calibrating the spray model constants

    Axial

    Wang, 2014 Hour 7: Heat transfer and Spray Combustion Research

    http://www.sandia.gov/ecn/

  • Reacting conditions - Soot formation vs. Ambient temperature

    28 PCI-3-7, 2018

    R(mm)

    Z(m

    m)

    -10 0 10

    0

    10

    20

    30

    40

    50

    60

    0

    0.2

    0.4

    0.6

    0.8

    1

    1.2

    1.4

    R(mm)

    Z(m

    m)

    -10 0 10

    0

    10

    20

    30

    40

    50

    60

    0

    1

    2

    3

    4

    5

    6

    7

    R(mm)

    Z(m

    m)

    -10 0 10

    0

    10

    20

    30

    40

    50

    60

    0

    2

    4

    6

    8

    10

    12

    14

    R(mm)

    Z(m

    m)

    -10 0 10

    0

    10

    20

    30

    40

    50

    60 2

    4

    6

    8

    10

    12

    14

    16

    R(mm)

    Z(m

    m)

    -10 0 10

    0

    10

    20

    30

    40

    50

    60

    5

    10

    15

    20

    800 900 1000 1100 12000

    15

    30

    45

    60

    Expt. 255 species Present

    Lift-

    off l

    engt

    h [m

    m]

    Ambient Temperature [K]

    ECN_Spray-A n-C12Ambient density 22.8 kg/m3

    Solid-Expt.Open-Simulation

    15% O2

    800 900 1000 1100 12000.0

    0.5

    1.0

    1.5

    2.0

    2.5

    3.0

    Expt. Simultion

    Igni

    tion

    dela

    y [m

    s]

    Ambient Temperature [K]

    ECN_Spray-A n-C12Ambient density 22.8 kg/m3

    15% O2

    0 1 2 3 4 5 60

    15

    30

    45

    60

    75

    Soot

    [ug]

    Time [ms]

    800 K 850 K 900 K 1000 K 1200 K

    ECN Spray-Adensity-22.8 kg/m3

    oxygen-15%

    850K 900K 1000K 1100K 1200K

    Soot ppm

    Skeen, 2016

    Wang, 2014 Hour 7: Heat transfer and Spray Combustion Research

  • Reacting conditions - Soot formation & model sensitivity

    29 PCI-3-7, 2018

    0 1 2 3 4 5 60

    5

    10

    15

    20

    Soot

    [g/k

    g-fu

    el]

    Time [ms]

    baseline surface*1.5 coagulation/3

    ECN Spray-A900K, 22.8 kg/m3

    R(mm)

    Z(m

    m)

    -10 0 10

    0

    10

    20

    30

    40

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    m)

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    R(mm)

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    m)

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    m)

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    0

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    1

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    1.8x 10

    -6

    R(mm)Z(

    mm

    )

    -10 0 10

    0

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    0

    0.2

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    1

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    1.8x 10

    -6

    R(mm)

    Z(m

    m)

    -10 0 10

    0

    10

    20

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    0

    0.2

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    1

    1.2

    1.4

    1.6

    1.8x 10

    -6

    C2H2 surface growth

    Soot particle coagulation

    baseline

    C2H2 assisted surface growth process is the most important process that affects the soot emission, followed by OH oxidation process;

    The surface growth process and the coagulation process affect the soot particle size;

    Wang, 2014 Part 5: Diesel and SI Engine combustion

  • Summary and current directions Integration of soot model with multi-component vaporization and chemistry models Extension to GDI and H/P/RCCI

    Organic fraction modeling: OF correlates with premixedness

    Soot diameter comparisons with TEM measurements obtained from various combustion modes

    InceptionH2 +

    C2H2 assisted surface growth

    Coagulation

    Coag

    ulatio

    n

    Oxidation by OH

    Oxidation by O2

    + CO + H2

    Gasoline/Diesel

    Fuel-aromatic assisted

    surface growth

    H2 +

    Need development/improvement

    Fuel breakdown + fuel aromatic led PAH growth

    30 PCI-3-7, 2018

    Hour 7: Heat transfer and Spray Combustion Research

    Qiu, 2015 Jiao, 2015

  • References

    31 PCI-3-7, 2018

    Hour 7: Heat transfer and Spray Combustion Research

    3-7:3 Diesel Engine Reference Book, Fig. 5.1, 2nd Edition, Challen, B. and Baranescu, R., Eds., 1998.

    3-7:4 Han, Z. and Reitz, R.D., "Turbulence Modeling of Internal Combustion Engines Using RNG k-e Models," Combust. Sci. and Tech. 106, 4-6, p. 267, 1995.

    3-7:4 Wang, B.-L., Bergin, M.J., Petersen, B.R., Miles, P.C., Reitz, R.D., and Han, Z., " Validation of the Generalized RNG Turbulence Model and Its Application to Flow in a HSDI Diesel Engine," SAE paper 2012-01-0140, 2012.

    3-7:5,10 Wiedenhoefer, J.F., and Reitz, R.D., “Multidimensional Modeling of the Effects of Radiation and Soot Deposition in Heavy-duty Diesel Engines,” SAE paper 2003-01-0560, SAE Transactions, Volume 112, Section 3, Journal of Engines, pp. 784-804, 2003.

    3-7:6 Wiedenhoefer, J.F., and Reitz, R.D., “A Multidimensional Radiation Model for Diesel Engine Simulations with Comparison to Experiment,” Numerical Heat Transfer: International Journal of Computation and Methodology Part A: Applications, 44 (7): 665-682, 2003a.

    3-8:7 Yoshikawa, T., and Reitz, R.D., "Effect of Radiation on Diesel Engine Combustion and Heat Transfer," JSME Journal of Thermal Science and Technology, February, 2009.

    3-7:8,9 Wiedenhoefer, J., F., and Reitz, R.D., “Modeling the Effect of EGR and Multiple Injection Schemes on I.C. Engine Component Temperatures,” Journal of Numerical Heat Transfer, Part A, Vol. 37, pp. 673-694, 2000.

    3-7:11 Naber, J. D. and Siebers, D. L., "Effects of Gas Density and Vaporization on Penetration and Dispersion of Diesel Sprays, SAE Technical Paper 960034, 1996.

    3-7:11 Siebers, D.L., “Liquid-Phase Fuel Penetration in Diesel Sprays,” SAE 980809, 1998.

    3-7:11 Pickett, L., Sandia National Laboratory, "Engine Combustion Network", https://share.sandia.gov/ecn/ , 2007.

  • References

    32 PCI-3-7, 2018

    Hour 7: Heat transfer and Spray Combustion Research

    3-7:12,13 Dec, J. E., “A Conceptual Model of D.I. Diesel Combustion Based on Lased Sheet Imaging,” SAE Technical Paper No. 970873, SAE Transactions, 106(3), 1319-1348, 1997.

    3-7:13 Musculus, M. P. B., “Multiple Simultaneous Optical Diagnostic Imaging of Early-Injection Low-Temperature Combustion in a Heavy-Duty Diesel Engine,” SAE Paper 2006-01-0079, 2006.

    Slide 3-7:14

    Patterson, M. A., Kong, S.-C., Hampson, G. J. and Reitz, R.D., "Modeling the Effects of Fuel Injection Characteristics on Diesel Engine Soot and NOx Emissions," SAE Paper 940523, SAE Transactions, Vol. 103, Section 3, Journal of Engines, pp. 836-852, 1994.

    Kong, S.-C., Sun, Y., and Reitz, R.D., “Modeling Diesel Spray Flame Lift-Off, Sooting Tendency and NOx Emissions Using Detailed Chemistry with Phenomenological Soot Model,” ASME J. Gas Turbines and Power, Vol. 129, pp. 245-251, 2007.

    Vishwanathan, G., and Reitz, R.D., "Numerical Predictions of Diesel Flame Lift-off Length and Soot Distributions under Low Temperature Combustion Conditions," SAE 2008-01-1331, SP-2185, Compression Ignition Combustion Processes, 2008.

    Vishwanathan, G., and Reitz, R.D., "Modeling Soot Formation Using Reduced PAH Chemistry in n-Heptane Lifted Flames with Application to Low-Temperature Combustion," ASME J. Gas Turbines and Power, Vol. 131 / 032801/1-7, 2009.

    Kazakov, A., and Foster, D.E., “Modeling of Soot Formation during DI Diesel Combustion Using a Multi-Step Phenomenological Model,” SAE paper 982463, 1998.

    Tao, F., Reitz, R.D., Foster, D.E., and Liu, Y., "A Nine-Step Phenomenological Diesel Soot Model Validated Over a Wide Range of Engine Conditions," International Journal of Thermal Sciences, Vol. 48, pp. 1223–1234, 2009.

    Tao, F., Foster, D.E., and Reitz, R.D., “Soot Structure in a Conventional Non-Premixed Diesel Flame,” SAE Paper 2006-01-0196, SAE Transactions, Vol. 115, Section 4, Journal of Fuels & Lubricants, 2006.

    Tao, F., Foster, D.E., and Reitz, R.D., “Characterization of Soot Particle Distribution in Conventional, Non-Premixed DI Diesel Flame Using a Multi-Step Phenomenological Soot Model,” Proceedings of 31st International Symposium on Combustion, The Combustion Institute, Pa, 2006

    Kennedy, I. M. (1997) Models of soot formation and oxidation. Prog. Energy Combust. Sci., 23, 95.

    Tree DR, Svenson KI. 2007. Soot processes in compression ignition engines. Progress in Energy and Combustion Science 33:272-309

    Vishwanathan, G., and Reitz, R.D.,”Development of a Practical Soot Modeling Approach and its Application to Low Temperature Diesel Combustion,” Combustion Science and Technology, Vol. 182, Issue 8, pp.1050-1082, 2010.

  • References

    33 PCI-3-7, 2018

    Hour 7: Heat transfer and Spray Combustion Research

    3-7:15 Hiroyasu, H., and Kadota, T., “Models for Combustion and Formation of Nitric Oxide and Soot in DI Diesel Engines,” SAE paper 760129, SAE Transactions, 85, 1976.

    3-7:15 Nagle, J., and Strickland-Constable, R.F., “Oxidation of Carbon between 1000-2000°C,” Proceedings of the fifth carbon conference, 1, Pergammon Press, 154, 1962.

    3-7:16,17 Pickett, L. M., and Siebers, D.L., “Soot in Diesel Fuel Jets: Effects of Ambient Temperature, Ambient Density, and Injection Pressure,” Combustion and Flame, 138, 114-135, 2004.

    3-7:16,17 Vishwanathan, G., and Reitz, R.D., "Numerical Predictions of Diesel Flame Lift-off Length and Soot Distributions under Low Temperature Combustion Conditions," SAE 2008-01-1331, SP-2185, Compression Ignition Combustion Processes, 2008.

    3-7:18 Tao, F., Foster, D.E., and Reitz, R.D., “Characterization of Soot Particle Distribution in Conventional, Non-Premixed DI Diesel Flame Using a Multi-Step Phenomenological Soot Model,” Proceedings of 31st International Symposium on Combustion, The Combustion Institute, Pa, 2006

    3-7:19 Xi, J. and Zhong, B., 2006, “Reduced Kinetic Mechanism of n-Heptane Oxidation in Modeling Polycyclic Aromatic Hydrocarbon Formation in Diesel Combustion,” Chemical Engineering and Technology, 29, pp.1461-1468.

    3-7:19 Wang, H. and Frenklach, M. (1997) A detailed kinetic modeling study of aromatics formation in laminar premixed acetylene and ethylene flames. Combust.Flame, 110, 173.

    3-7:19,20 Vishwanathan, G., and Reitz, R.D., "Modeling Soot Formation Using Reduced PAH Chemistry in n-Heptane Lifted Flames with Application to Low-Temperature Combustion," ASME J. Gas Turbines and Power, Vol. 131 / 032801/1-7, 2009.

    3-7:20 Pickett, L.M., and Idicheria, C.A., “Effects of Ambient Temperature and Density on Soot Formation under High EGR Conditions,” THIESEL 2006 Conference on Thermo- and Fluid Dynamic Processes in Diesel Engines, 2006.

    3-7:21-24 Vishwanathan, G., and Reitz, R.D., ”Development of a Practical Soot Modeling Approach and its Application to Low Temperature Diesel Combustion,” Combustion Science and Technology, Vol. 182, Issue 8, pp.1050-1082, 2010.

    3-7:21 Leung, K. M., Lindstedt, R. P. and Jones, W. P. (1991) A simplified reaction mechanism for soot formation in nonpremixed flames. Combust.Flame, 87, 289.

    3-7:22 Fenimore, C. P. and Jones, G. W. (1967) Oxidation of soot by hydroxyl radicals. J.Phys.Chem., 71, 593.

    3-7:25-29 Wang, H., Ra, Y., Jia, M., and Reitz, R.D., "Development of a Reduced n-dodecane-PAH Mechanism and its Application for n-dodecane Soot Predictions," FUEL, Vol. 136, pp. 25-36, http://dx.doi.org/10.1016/j.fuel.2014.07.028, 2014.

  • References

    34 PCI-3-7, 2018

    Hour 7: Heat transfer and Spray Combustion Research

    3-7:28 Skeen, S., Manin, J., Pickett, L., Cenker, E., Bruneaux, G., Kondo, K., Aizawa, T., Westlye, F., Dalen, K., Ivarsson, A., Xuan, T., Garcia-Oliver, J.M., Pei, Y., Sibendu Som, S., Hu, W., Reitz, R.D., Lucchini, T., DErrico, G., Farrace, D., Pandurangi, S.S., Wright, Y.M., Chishty, M.A., Bolla, M., and Hawkes, E. , "A Progress Review on Soot Experiments and Modeling in the Engine Combustion Network (ECN)," SAE Int. J. Engines 9(2): doi:10.4271/2016-01-0734., 2016

    3-7:30 Qiu, L., and Reitz, R.D., "Investigating Fuel Condensation Processes in Low Temperature Combustion Engines," Journal of Engineering for Gas Turbines and Power, Vol. 137, pp. 101506-1, DOI: 0.1115/1.4030100, 2015.

    3-7:30 Jiao, Q., and Reitz, R.D., "The Effect of Operating Parameters on Soot Emissions in GDI Engines," SAE Int. J. Engines 8(3):2015, doi: 10.4271/2015-01-1071, 2015

    Slide Number 1Slide Number 2Slide Number 3Heat transferSlide Number 5Soot and gas absorptionSlide Number 7Slide Number 8Slide Number 9Slide Number 10Spray Combustion ResearchSlide Number 12Diesel combustion regimesSoot ModelingTwo-step modelSlide Number 16Slide Number 17Phenomenological�soot modelsReduced PAH mechanismPAH speciesSoot model implementationSlide Number 22Slide Number 23Slide Number 24Slide Number 25Slide Number 26Slide Number 27Slide Number 28Slide Number 29Summary and current directionsReferencesReferencesReferencesReferences