state of the art of partially premixed combustion (ppc)

State of the art ofPartially Premixed Combustion (PPC)Partially Premixed Combustion (PPC)

Martin Tunér

Division of Combustion EnginesDepartment of Energy Sciences

Lund University

Conclusion

• It is impossiblep

Lund University / Combustion engines / Martin Tunér / CRC 2014

I have good news!• Engine research is successful!


O tliOutline

PPC• Fuel flexibility• Efficiency• Challenges


Research groups into PPC

A loved child has many names• Gautam Kalghatgi - Saudi Aramco – PPCI, GCI• Lund – PPC• Delphi – GDCI

Eindhoven PPC• Eindhoven - PPC• Wisconsin Madison – PPCI, GCI• Sandia – PPCI, LTGC,• ...• ...


PPC in production?

"achieve diesel levels of fuel efficiency with conventional gasoline," according to Nayan


Engineer (yes, his last name is Engineer), one of Hyundai's powertrain gurus. What's more, Engineer says the GDCI engine will offer "equal to better performance than conventional gasoline engines" and will have a "lower system cost [than] diesel engines."

P ti ll P i d C b ti PPCPartially Premixed Combustion, PPC

Lund University / Combustion engines / Martin Tunér / CRC 2014 7

Burn rate and ηT

Optimum Thermodynamic efficiency

150

C l P [b ]

High heat losses

Low effective expansion ratio

100

Cyl Pressure [bar]Inj Signal [a.u.]RoHR [J/CAD]

50

-80 -60 -40 -20 0 20 400

CAD [TDC]


Premixedness8

Emissions

0.35

0.4

0.45

0.5

0 4

0.5

0.6

h]

Brake NOxUS10EU VI

0.15

0.2

0.25

0.3

Soo

t [FS

N]

0.2

0.3

0.4

Bra

ke N

Ox

[g/k

Wh

5 10 15 20 25 300

0.05

0.1

Gross IMEP [bar]0 5 10 15 20 25 30

0

0.1

Gross IMEP [bar]

1.4

1.6

1.8

2

]

Brake HCUS 10EU VI

20

25

]

Brake COUS 10EU VI

0.6

0.8

1

1.2

Bra

ke H

C [g

/kW

h]

10

15B

rake

CO

[g/k

Wh]


0 5 10 15 20 25 300

0.2

0.4

Gross IMEP [bar]0 5 10 15 20 25 30

0

5

Gross IMEP [bar]

F l fl ibilit PPCFuel flexibility - PPC


Tested Load Area

25

Stable operational load vs. fuel type

20

25

15

gros

s [b

ar]

5

10

IME

P g

20 30 40 50 60 70 80 90 1000

5


RON [-]

12

Fuel flexibility:New opportunity for WTW efficient fossil&biofuels?Choice of the cheapest fuel of the day?Local fuel availability?

ONDiesel Gasoline?FAME EthanolMethanol

ButanolDME

B10…E85E5

?E85E5…


Fuel compositionLTR as a function of n-heptaneLTR as a function of n heptane

4.5

5

R2=0.98

3.5

4

R [%

]

2 5

3

actio

n LT

R

PRF70

2

2.5

Fra TRF

TERFcpERFTERF

28 30 32 34 36 38 40 421

1.5

H t [%]

TERFcriticalDataExper


n-Heptane [%]

NOx, HC & CO emissions 15

3 15 35

%]

10

uel]2.4

2.6

2.8

3

%]

10

el]

33.5

34

34.5

35

HC

Tolu

ene

[%

5

HC

[g/k

g Fu

1.8

2

2.2

Tolu

ene

[%

5

CO

[g/k

g Fu

31.5

32

32.5

33

CO

150.18

Ethanol [%]

0 1 2 3 4 5 6 7 8 9 10

01.4

1.6

Ethanol [%]

0 1 2 3 4 5 6 7 8 9 10

030.5

31CO

e [%

]

10

Fue

l]

0.14

0.15

0.16

0.17

NO

Tolu

ene

5

NO

x [g/k

g

0.1

0.11

0.12

0.13 NOx


Ethanol [%]

0 1 2 3 4 5 6 7 8 9 10

0

0.09

Smoke emissions

0.9

PRF60

0 6

0.7

0.8 InjP 800 barIjnP 1000 barInjP 1200 bar

TRFERF

0.4

0.5

0.6

mok

e [F

SN]

0.2

0.3

Sm

2 4 6 8 10 12 14 160

0.1

CA50 [deg]


CA50 [deg]

EGR Effect -Soot

(FuelMEP ~20.5bar)MK1 Gasoline Ethanol

8

EGR~48%EGR~38% 8

EGR~48%EGR~38% 8

EGR~48%EGR~38%

6

FSN

] 6FS

N] 6

FSN

]

4

Soo

t[F

4

Soo

t[F

4

Soo

t[F0

2

0

2

0

2


1 1.5 20

[-]

1 1.5 2

0

[-]1 1.5 2

0

[-]17

Peak Pressure Rise Rate

30

20

25

CA

D]

15

20

RR

[bar

/C

48%EGR

10

MP

R

MK1G li

48%EGR38%EGR

1.5 2 2.5 35

Intake Pressure [bar]

GasolineEthanol

Lund University / Combustion engines / Martin Tunér / CRC 2014 182013-01-2702


Engine Emissions

10 MK1

48%EGR

2.5 MK1G li

48%EGR38%EGR

6

8

FSN

]

GasolineEthanol

38%EGR30%EGR

1.5

2

/kW

h]

GasolineEthanol

38%EGR30%EGR

2

4

Soo

t [F

0.5

1

NO

x [g

/1.5 2 2.5 3

0


1.5 2 2.5 3

0


Lund University / Combustion engines / Martin Tunér / CRC 2014 192013-01-2702

Effi i PPCEfficiency - PPC


System model (Std Scania components unless mentioned)

Experimental combustion, HT and flowFrom SCE

CAC 60% more pipes

than std unitthan std unit

Piping slightly increased in

size

BorgWarneroff-the-shelfTwo-stage

Turbo

EATS Low Pressure EGR route


B k ffi iBrake efficiency


E h t T b f EATSExhaust T before EATS


Loss comparison CDC versus PPC @A75


We must understand in-cylinder processes!!!


In-cylinder temperature distribution

CDC

Fridriksson et al, SAE 2011-01-1838, 2011

PPC5.4% F.E.

Lund University / Combustion engines / Martin Tunér / CRC 2014 26 26

Ch ll PPCChallenges - PPC


PPC Pros.• Simple and rugged

Challenges• Show don’t tell...

• Fuel flexible• High efficiency

Hi h l d

• Idle – low load (High RON)• Transient emissions

C b ti i• High load • Low emissions

• Combustion noise• Difference LD - HD• WHAT IS PPC?• WHAT IS PPC?


I iti t tIgnition zone structuresFlame propagation

T HO2

Premixed charge ignitionPremixed charge ignition


5 CAD bTDC

Conclusions• PPC uses fairly simple hardware and is very fuel flexible. Can the fuel

flexibility be exploited for use of less processed and more WTW efficient fuels – aka naphtha, raw-methanol ...?

EURO VI / US 10 li t ti b hi d i b f• EURO VI / US 10 compliant operation can be achieved in a number of ways depending on fuel, for instance with stoichiometric ethanol PPC. Which is the best way forward?

• PPC has very high GIE and system analysis indicate that a “real” PPC engine can have above 48% BTE. Boosting – EGR routing – HT are key factors. Can high BTE be achieved in a real engine?g g

• Low load operation is challenging with high RON fuels. Can a SI system be avoided?

• DNS indicate that PPC is a combination of premixed ignition and flame front combustion. Can this be proved with optical investigations and how d diff t f l i fl th d f b ti ?


does different fuels influence the modes of combustion?

30

Lund University, Sweden


Lund University47000 students

Faculty of Engineering(Lund Institute of Technology)

9600 students

Department of Energy Sciences(Staff 90 persons)

9600 students

Department of Engineering Department

Division of Division of Division of Division ofDivision of

Physics

Division of

pof Automatic Control

Prof. Anders RantzerDivision of

Thermal Power Engineering

Prof.Mohsen Assadi

Division ofHeat transfer

Prof. Bengt Sundén

Division ofFluid dynamics

Prof.Lazlo Fuchs

Division ofCombustion Engines

Prof. Bengt Johansson

Division ofEnergy economics and planningProf.

i

Division ofCombustion Physics

Prof. Marcus Aldén

(staff 35 persons)


Mohsen Assadi Bengt Sundén Lazlo Fuchs Bengt Johansson(staff 32 persons)

L. Törnqvist Marcus Aldén(staff 40 persons)

Refurbished and extended lab


state of the art of partially premixed combustion (ppc)

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