possible ”road” map of solving new spray combustion ... · possible ”road” map of solving...

Chalmers University of Technology

HTCES – High Tech Cars and Engines – Modena, Italy – May, 26-27 2005

Valeri I. Golovitchev

POSSIBLE ”ROAD” MAP OF SOLVING NEW SPRAY COMBUSTION PROBLEMS IN COMPRESSION IGNITED ENGINE MODELING

Chalmers University of TechnologyGothenburg, Sweden




Valeri I. Golovitchev

POSSIBLE ”ROAD” MAP OF SOLVING NEW SPRAY COMBUSTION PROBLEMS IN COMPRESSION IGNITED ENGINE MODELING


With contribution of:Mr. J. GustavssonDr. N. Nordin

Dr. Y. Murata (Waseda University, Japan)

Dr. L. Montorsi (University of Modena and Reggio Emilia)

Miss A. Häggström (SCANIA AB)

Miss M. Bergman


HTCES – High Tech Cars and Engines – Modena, Italy – May, 26-27 2005HTCES – High Tech Cars and Engines – Modena, Italy – May, 26-27 2005



Spray atomization models



‘breakup’

parcel

droplet rp0

parent

child

new parent−

= −p p c

b

dr r rdt t Λ

= Λ

0 KH

c RT

Br

2

τ

Λ Ω= Ω

1 p0

KH KHb

RT

3.726 B r

tC

Λ Ω

Λ ΩKH KH

RT RT

,

,

ΛKHΛ0 KH2B

ΛRT

ΛRT

ρ=ρ

lb b 0

g

L C d

Hybrid Kelvin-Helmholtz/ Rayleigh-Taylor droplet breakup model

*



Droplet drag model

ρ= ρ = ⋅

uuru

ur

ur

rup d

2gp

l d f

Udv Um V A

dt 2 Ua C

+

23d

d

24 11 Re

Re 6=d,sphereC

0.424

≤dRe 1000

>dRe 1000

= +d,sphered C (1 2.C 632 y)

Taylor Analogy Model

ρ σ µ= − −

ρ ρ ρ&& &

2g l

2 3 2l l l

U2 8 5y y y

3 r r r

Droplet’s equation of motion

Modified Stokes’ low

= ⋅ + ⋅r r rr

t pg jg a j

nozzle

uuuuuurpv

uuurg

uurj

uuuuuurpx

the direction of travel



Improved 3-D spray model

850.0 K, 4.03 MPa, 16.0 kg/m3

Dis

tanc

e fr

om th

e no

zzle

m

m

0

60

20

40

80

Pen

etra

tion

mm

Time ms

Injection duration

Am

ount

of e

vapo

rate

d fu

el m

g

Time ms

Injection quantity

( Wall )

Droplet diameter mm

Fuel vapor g/cm3

0.0 0.13 0.26

0.0 0.023 0.0045

0

20

40

60

80

0 0.3 0.6 0.9 1.2 1.5

0

4

8

12

16

0 0.5 1 1.5 2 2.5

KH-RT model

KH model

KH-RT model

KH model

KH model

Liquid Vapor



Validation of 3-D spray modelD

sita

nce

from

the

nozz

le

mm

0

60

20

40

80

Pen

etra

tion

mm

Time ms

KH-RT modelExp.

850.0 K, 4.03 MPa, 16.0 kg/m3

KH-RT model

Exp.

( Wall )Droplet diameter mm

Fuel vapor g/cm3

0.0 0.13 0.26

0.0 0.023 0.0045

0

20

40

60

80

0 0.2 0.4 0.6 0.8 1 1.2

KH-RT model can predict the measured maximum penetration of the liquid phase under high pressure and temperature conditions

KH-RT model

Exp.



Multi-Stage Fuel Injection - II

(Pilot and Post Injection in Spray Combustion Modeling)

Series of smaller injections must be optimized to achieve design goals



Fuel compositions studied

Fuel A-D• Different three-component mixtures• Large spread in volatility

Fuel E• Blend of n-heptane and toluene• Used as fuel vapour representation in

the Diesel surrogate model (Chalmers)• Species with similar volatility



Fuel mixtures in the study

0.30----0.70Fuel E (mole)

-0.600.300.10--Fuel D (mass)

-0.330.330.33--Fuel C (mass)

-0.100.300.60--Fuel B (mass)

-0.33--0.330.33Fuel A (mass)

tolueneC7H8

n-hexadecaneC16H34

n-dodecaneC12H26

iso-octaneC8H18

n-decaneC10H22

n-heptaneC7H16

• Myong, K., Suzuki, H., Senda, J., Fujimoto, H., Spray Structure of Multi-Component Fuels on Evaporating Transient Diesel Sprays, Thiesel Conference, Valencia (2004).

• Myong, K., Arai, M., Suzuki, H., Senda, J., Fujimoto, H., Vaporization Characteristics and Liquid-Phase Penetration for Multi-Component Fuels, SAE 2004-01-0529 (2004).



Large volatility differences (A)

0

1

0 0,0001 0,0002t (s)

d2 /d02 (

-)

Cold-start

Idle

• No notable sequential evaporation.

• Volatility differences are reduced at high temperatures and pressures.



Large volatility differences (A)

Idle

0

1

0 0,0001t (s)

Mas

s fr

actio

ns (

-)

n-heptanen-decanen-hexadecane But…

Mass fractions in dropletchanges during evaporation.



Large volatility differences (B-D)Cold-start

0

1

0 0,0001 0,0002t (s)

d2 /d0

2 (-)

Fuel BFuel CFuel D

Idle

0

1

0 0,0001t (s)

d2 /d02 (

-)

Fuel BFuel CFuel D

• No notable sequential evaporation.• Evaporation rates are similar.• Heat-up times differ.



Large volatility differences (B-D)

Idle, Fuel C

0

1

0 0,0001t (s)

Mas

s fr

actio

ns

iso-octanen-dodecanen-hexadecane

• Mass fractions in droplet changes during evaporation process.



Similar volatility (E)

Idle

0

1

0 0,00005t (s)

d2 /d02 (

-)

Pure n-heptanePure tolueneFuel E

Evaporation rates ofpure species andthe mixture are similar.



Idle

0

1

0 0,00005t (s)

d2 /d02 (

-)

Pure n-heptanePure tolueneFuel E

Evaporation rates ofpure species andthe mixture are similar.

Similar volatility (E)



Droplet Spray Collision Model: New Approach

Binary collision schematics in relative motion


30 deg. 60 deg. 90 deg.



Regime diagram for turbulent combustion

* Borghi(1995), Peters(1999), Poinsot(1991)

Laminar plane flame fronts

Well-stirred combustion

Da<<1

Da=1

Wrinkled flame fronts

Corrugated flamelets

Distributed combustion

Peters criterion (Ka=100)

Klimov -Williams criterion (Ka=1)

Thin reaction zone

10-1 100 101 102 103 104

10-1

100

101

102

103

104

lI/δL

u rms/S

L

Ka>1

Torn flame fronts

Island formation

Ka~1

Ka<1

Da>>1

Ret =1

Laminar plane flame fronts

Well-stirred combustion

Da<<1

Da=1

Wrinkled flame fronts

Corrugated flamelets

Distributed combustion

Peters criterion (Ka=100)

Klimov -Williams criterion (Ka=1)

Thin reaction zone

10-1 100 101 102 103 104

10-1

100

101

102

103

104

lI/δL

u rms/S

L

Ka>1

Torn flame fronts

Island formation

Ka~1

Ka<1

Da>>1

Ret =1

Ret=urmslI/νTurbulent Reynolds number

Damkohler number

Karlovitz number

Da=τI/τchem

Ka=τchem/τη

dominated by chemical kinetics

dominated by turbulent mixing



Reactive volume = computational cell

Averaged concentrations at the beginning of the integration step: [X] i

0 Averaged concentrations at the end of the integration step: [X]i1

Reaction zone : mixed

Reaction zone:

(treated as a PSR**)

[X]i

Time-averaged concentrations

*PaSR: Partially Stirred Reactor **PSR: Perfectly Stirred Reactor

mixed and reacting

Conceptual schematic diagram of the PaSR* model

[Xs]0

Spe

cies

con

cent

ratio

n ?

?

t tctmixTime

[Xs]1

[Xs]

− −= = = − = −

τ τ τ τ

1 1 0 11s s s s s s s

r sc mix c

d[X ] [X ] [X ] [X ] [X ] [X ] [X ]f ([X ] ) ,

dt

tmix: the micro-mixing timetc: the chemical reaction timet : the calculation time step

−

=

∂ −τ = τ = − ≈ ε ∂ + τ

e1

s s

01 r s r

mix mix c 0s s r[ X ] [ X ]

f ([X ])k fC ,

[X ] [X ] term

by V.I.Golovitchev



Engine geometry andoperating condition

Chemical kinetic calculation (PaSR model)

Output files

Read thermodynamic properties

Fluid dynamic calculation(RNG k-emodel)

KIVA-3V

Spray breakup calculation(KH-RT model)

Elementaryreactions (chem.inp)

CHEMKIN libraries for reading binary file

Thermodynamic properties(therm.dat)

CHEMKIN Interpreter

Binary file for thermal properties

and rate parameters

CHEMKIN-II

Integration PaSR Model into KIVA3 Code



0.001

0.01

0.1

1

10

100

1000

10000

0.7 0.9 1.1 1.3 1.5 1.7

0.001

0.01

0.1

1

10

100

1000

10000

0.7 0.9 1.1 1.3 1.5 1.7

LLNL

COSMO Oil

n-heptaneoxidation

mechanism( f =1.0) Ig

nitio

n de

lay

ms

http://www-cms.llnl.gov/combustion/combustion2.html

Combustion and Flame

133 (2003) 467-481

Igni

tion

dela

y m

s

0.01

0.1

1

10

100

1000

10000

0.7 0.9 1.1 1.3 1.5 1.7

0.001

0.01

0.1

1

10

100

1000

10000

0.7 0.9 1.1 1.3 1.5 1.7

29 species , 52 reactions

http://www.erc.wisc.edu/modeling/modeling_index.htm

Chalmers Univ.

1000/T 1/K

62 species , 255 reactionshttp://www.tfd.chalmers.se/~valeri/MECH.html

V.I.Golovichev

1000/T 1/K

561 species, 2539 reactions160 species, 1540 reactions

32 species , 55 reactions

10 MPa

4.2 MPa

1.35 MPa

0.32 MPa

0.1 MPa

S.Tanaka

ERC



Process of Soot and NO formation modelSoot formation mecahnism

NO formation mecahnism

A2R5 ? x C(S)Graphitization5

Detailed chemistryAcetylene oxidation4

Detailed chemistryAcetylene formation2

Detailed chemistryPrecursor radical oxidation

3

6

1

No.

C(S)+O2 ? O+COC(S)+CH3 ? H+C2H2

C(S)+OH ? CO+HSoot oxidation

Detailed chemistry up to A2R5

Precursor radical formation

Chemical reactionProcess+C2H2

+C2H2

+C2H2

+C2H2

+C2H2

-H2

-H2

-H

+H

-H

+H

(A2R5)

Phenyl Naphthyl

Acenaphthylene

HACA* mechanism by Frenklach et al.

N2+O ? NO+N N+O2 ? NO+ON+OH ? NO+H

Extended Zel’dovichmechanism

Mechanism Chemical reaction* : H-abstraction, C2H2 addition

+



Soot NO

1000 1400 1800 2200 2600 3000 1000 1400 1800 2200 2600 3000

Temperature K Temperature K

Equ

ival

ence

ratio

F

109876543210

109876543210

Smokeless Rich Combustion by Reducing Temperature Akihama et al.

Desirable Path Kamimoto et al.

Equ

ival

ence

ratio

FMK combustion

HCCI Fuel : n-heptane, P : 6 MPa, reaction time : 1.0 ms

zero-dimensional calculation by using CHEMKIN-IICharacteristics of reaction mechanism on F -T map



1000 1400 1800 2200 2600 3000

1098765432101000 1400 1800 2200 2600 3000

109876543210

109876543210

1000 1400 1800 2200 2600 3000

1098765432101000 1400 1800 2200 2600 3000

109876543210

109876543210

Pressure Dependence of Soot-F -T map

1000 1400 1800 2200 2600 3000

1098765432101000 1400 1800 2200 2600 3000

109876543210

109876543210

Temperature K Temperature K Temperature K

1 MPa 3 MPa 6 MPa

Equ

ival

ence

ratio

F

Fuel : n-heptane, reaction time : 1.0 ms, EGR 0%



Fuel : Diesel surrogate (70% n-heptane, 30% toluene)

Analysis of Emission Formations in Diesel Engines

Equivalence ratio – Temperature Soot-Nox maps



Fuel : Diesel surrogate (70% n-heptane, 30% toluene)

Analysis of Emission Formations in Diesel Engines

Equivalence ratio – Temperature CO maps



Engine specifications, the experimental and computational conditions

-6-5-10Start of injectiondeg.ATDC

39(1/4 Load)

75

36(1/4

Load)

100Injection pressure MPa

Common-rail injection systemInjection equipment

Natural AspirationAir intake system

16.0Compression ratio

Direct injection, single cylinder, water-cooled, 4-stroke-cycle

Type of engine

1000Engine speed rpm

2.147Displacement L

83(3/4

Load)Amount of fuel mg

135×150Bore×Stroke mm

F 0.26 mm×6 (150 deg.)Common-rail Injector

-120~ 120(IVC~ EVO)

Crank angle deg.ATDC

Pentium4 3GHz×1,1GB Memory

CPU

26×30×29(?=60 deg.)

Mesh size r×?×Z

(@-180 deg.ATDC)

A B C D



PaSR

model

validation



0

1

2

3

4

5

6

7

-40 -30 -20 -10 0 10 20 30 40 50 600

50

100

150

200

250

300

350

400

450

500

In-cylinder mass histories of


Pre

ssur

e M

Pa

R.H

.R

J/de

g.

D

?inj= -6 deg.ATDC

3/4 Load

MeasuredCalculated

characteristic chemical species



In-cylinder distribution of temperature and fuel in the liquid phase

Droplet diameter mm

Temperature K

0.0 0.13 0.26

450 1375 2300

5 deg.ATDC 7 deg. ATDC 9 deg. ATDC 11 deg. ATDC-3 deg.ATDC -1 deg. ATDC 1 deg. ATDC 3 deg. ATDC

5 deg.ATDC 7 deg. ATDC 9 deg. ATDC 11 deg. ATDC-3 deg.ATDC -1 deg. ATDC 1 deg. ATDC 3 deg. ATDC



0

0.5

1

1.5

2

2.5

3

3.5

4

-20 0 20 40 60 80 100 120

0

0.2

0.4

0.6

0.8

1

1.2

1.4

1.6

-20 0 20 40 60 80 100 120

0

0.01

0.02

0.03

0.04

0.05

1 20

1 2

Cal

cula

ted

soot

mas

s m

gN

O m

ass

mg

soot

mas

s m

g

1/4 Load3/4 Load

1/4 Load 3/4 Load

MeasuredCalculated

1/4 Load3/4 LoadMeasured

Soot NO


CD

CD

D

(PM)

15 deg.

30 deg.

45 deg.

60 deg.

(ATDC)

Formation histories of soot and NO

(1000 ppm) (3000 ppm)



Modeling of Isotta Fraschini IF-1300 Marine DI Diesel engine



Modeling of Volvo NED5 DI Diesel engine



Modeling of Volvo DI NED5 and D12 Diesel engines

Volvo Car NED5 Volvo Powertrain D12

HCCI Mode MK Combustion



New problem: Free Piston, FP, Engine Modeling

Schematic of the FP combustion chamber FP operation modeling




Acknowledgments

This work was supported by Chalmers Combustion Engine

Research Center, CERC

possible ”road” map of solving new spray combustion ... · possible ”road” map of solving...

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