Path to High Efficiency Gasoline Engine · 1 Prof. Bengt Johansson Division of Combustion Engines....

102
Prof. Bengt Johansson Division of Combustion Engines Department of Energy Sciences Lund University SI HCCI PPC Path to High Efficiency Gasoline Engine

Transcript of Path to High Efficiency Gasoline Engine · 1 Prof. Bengt Johansson Division of Combustion Engines....

Page 1: Path to High Efficiency Gasoline Engine · 1 Prof. Bengt Johansson Division of Combustion Engines. Department of Energy Sciences. Lund University. SI HCCI PPC. Path to High Efficiency

1

Prof. Bengt Johansson

Division of Combustion EnginesDepartment of Energy Sciences

Lund University

SI HCCI PPC

Path to High Efficiency Gasoline Engine

Page 2: Path to High Efficiency Gasoline Engine · 1 Prof. Bengt Johansson Division of Combustion Engines. Department of Energy Sciences. Lund University. SI HCCI PPC. Path to High Efficiency

2

Scania diesel engine running on gasoline

0 2 4 6 8 10 12 1420

25

30

35

40

45

50

55

60

Gross IMEP [bar]

Gro

ss In

dica

ted

Effi

cien

cy [%

]

Group 3, 1300 [rpm]

FR47333CVXFR47334CVXFR47336CVX

!

ηi=57% = Isfc =147 g/kWh (@43 MJ/kg heating value)

Page 3: Path to High Efficiency Gasoline Engine · 1 Prof. Bengt Johansson Division of Combustion Engines. Department of Energy Sciences. Lund University. SI HCCI PPC. Path to High Efficiency

Outline

• HCCI and fuel efficiency– 50% thermal efficiency

• Partially premixed combustion, PPC– Background

– Why gasoline is the best diesel engine fuel

– 56% thermal efficiency in car size engine

– 57% thermal efficiency in truck size engine

– Why 55% thermal efficiency is better than 57%

– How to reach 26 bar IMEP with US10 NOx, PM, HC and CO engine out

3

Page 4: Path to High Efficiency Gasoline Engine · 1 Prof. Bengt Johansson Division of Combustion Engines. Department of Energy Sciences. Lund University. SI HCCI PPC. Path to High Efficiency

Outline

• HCCI and fuel efficiency– 50% thermal efficiency

• Partially premixed combustion, PPC– Background

– Why gasoline is the best diesel engine fuel

– 56% thermal efficiency in car size engine

– 57% thermal efficiency in truck size engine

– Why 55% thermal efficiency is better than 57%

– How to reach 26 bar IMEP with US10 NOx, PM, HC and CO engine out

4

Page 5: Path to High Efficiency Gasoline Engine · 1 Prof. Bengt Johansson Division of Combustion Engines. Department of Energy Sciences. Lund University. SI HCCI PPC. Path to High Efficiency

Efficiencies?

5

Page 6: Path to High Efficiency Gasoline Engine · 1 Prof. Bengt Johansson Division of Combustion Engines. Department of Energy Sciences. Lund University. SI HCCI PPC. Path to High Efficiency

Energy flow in an IC engineFuelMEP

QhrMEP

IMEPgross

lMEPnet

BMEP

QemisMEP

QlossMEP

QhtMEP

QexhMEP

PMEP

FMEP

Combustion efficiency

Thermodynamic efficiency

Gas exchange efficiency

Mechanical efficiency

Net Indicated efficiency

Brake efficiency

Gross Indicated efficiency

FuelMEP

QhrMEP

IMEPgross

lMEPnet

BMEP

QemisMEP

QlossMEP

QhtMEP

QexhMEP

PMEP

FMEP

Combustion efficiency

Thermodynamic efficiency

Gas exchange efficiency

Mechanical efficiency

Net Indicated efficiency

Brake efficiency

Gross Indicated efficiency

ηηηηη MechanicaleGasExchangmicThermodynaCombustionBrake***=

Page 7: Path to High Efficiency Gasoline Engine · 1 Prof. Bengt Johansson Division of Combustion Engines. Department of Energy Sciences. Lund University. SI HCCI PPC. Path to High Efficiency

7

Thermodynamic efficiencySaab SVC variable compression ratio, VCR, HCCI, Rc=10:1-30:1; General Motors L850 “World engine”, HCCI, Rc=18:1, SI, Rc=18:1, SI, Rc=9.5:1 (std) Scania D12 Heavy duty diesel engine, HCCI, Rc=18:1;

Fuel: US regular Gasoline

SAE2006-01-0205

Page 8: Path to High Efficiency Gasoline Engine · 1 Prof. Bengt Johansson Division of Combustion Engines. Department of Energy Sciences. Lund University. SI HCCI PPC. Path to High Efficiency

All four efficiencies

8

Page 9: Path to High Efficiency Gasoline Engine · 1 Prof. Bengt Johansson Division of Combustion Engines. Department of Energy Sciences. Lund University. SI HCCI PPC. Path to High Efficiency

Problem with HCCI: Too fast combustion

9

Page 10: Path to High Efficiency Gasoline Engine · 1 Prof. Bengt Johansson Division of Combustion Engines. Department of Energy Sciences. Lund University. SI HCCI PPC. Path to High Efficiency

Phasing HCCI combustion late helps burn rate but reduce ηC

10Magnus Christensen Ph.D. thesis 2002

Page 11: Path to High Efficiency Gasoline Engine · 1 Prof. Bengt Johansson Division of Combustion Engines. Department of Energy Sciences. Lund University. SI HCCI PPC. Path to High Efficiency

Outline

• HCCI and fuel efficiency– 50% thermal efficiency

• Partially premixed combustion, PPC– Background

– Why gasoline is the best diesel engine fuel

– 56% thermal efficiency in car size engine

– 57% thermal efficiency in truck size engine

– Why 55% thermal efficiency is better than 57%

– How to reach 26 bar IMEP with US10 NOx, PM, HC and CO engine out

11

Page 12: Path to High Efficiency Gasoline Engine · 1 Prof. Bengt Johansson Division of Combustion Engines. Department of Energy Sciences. Lund University. SI HCCI PPC. Path to High Efficiency

BackgroundCombustion concepts

Spark Ignition (SI) engine (Gasoline,

Otto)

Compression Ignition (CI) engine (Diesel)

Homogeneous Charge Compression Ignition

(HCCI)

Partially premixed combustion (PPC)

Diesel HCCI

Spark Assisted Compression Ignition

(SACI)Gasoline HCCI

+ High efficiency

+ Ultra low NOx

-Combustion control

-Power density

+ Clean with 3-way Catalyst

- Poor low & part load efficiency

+ High efficiency- Emissions of NOx and

soot

+ Injection controlled- Less emissions

advantage

Page 13: Path to High Efficiency Gasoline Engine · 1 Prof. Bengt Johansson Division of Combustion Engines. Department of Energy Sciences. Lund University. SI HCCI PPC. Path to High Efficiency

Partially Premixed Combustion, PPC

13

-180 -160 -140 -120 -100 -80 -60 -40 -20

1000

2000

3000

4000

5000

6000p y

HC

[pp

m]

SOI [ATDC]-180 -160 -140 -120 -100 -80 -60 -40 -20

200

400

600

800

1000

1200

NO

x [p

pm]

Def: region between truly homogeneous combustion, HCCI, and diffusion controlled combustion, diesel

HCCI

PPC

CIPCCI

Page 14: Path to High Efficiency Gasoline Engine · 1 Prof. Bengt Johansson Division of Combustion Engines. Department of Energy Sciences. Lund University. SI HCCI PPC. Path to High Efficiency

PPC: Effect of EGR with diesel fuel

14

Load 8 bar IMEP

Abs. Inlet Pressure 2.5 bar

Engine Speed 1090 rpm

Swirl Ratio 1.7

Compression Ratio 12.4:1 (Low)

DEER2005

Scania D12 single cylinder

Page 15: Path to High Efficiency Gasoline Engine · 1 Prof. Bengt Johansson Division of Combustion Engines. Department of Energy Sciences. Lund University. SI HCCI PPC. Path to High Efficiency

1

43

2

Page 16: Path to High Efficiency Gasoline Engine · 1 Prof. Bengt Johansson Division of Combustion Engines. Department of Energy Sciences. Lund University. SI HCCI PPC. Path to High Efficiency

Lund/Delphi/Volvo PPC Project

16

NOx <0.3 g/kWhPM < 2 FSN usingSwedish MK1 diesel fuel

Volvo D13 Multi-cylinder engine

Adapted fromSAE paper 2009-01-1127

Page 17: Path to High Efficiency Gasoline Engine · 1 Prof. Bengt Johansson Division of Combustion Engines. Department of Energy Sciences. Lund University. SI HCCI PPC. Path to High Efficiency

Outline

• HCCI and fuel efficiency– 50% thermal efficiency

• Partially premixed combustion, PPC– Background

– Why gasoline is the best diesel engine fuel

– 56% thermal efficiency in car size engine

– 57% thermal efficiency in truck size engine

– Why 55% thermal efficiency is better than 57%

– How to reach 26 bar IMEP with US10 NOx, PM, HC and CO engine out

17

Page 18: Path to High Efficiency Gasoline Engine · 1 Prof. Bengt Johansson Division of Combustion Engines. Department of Energy Sciences. Lund University. SI HCCI PPC. Path to High Efficiency

18

PPC with low cetane diesel

Lic. Thesis by Henrik Nordgren 2005 and presented at DEER2005

Page 19: Path to High Efficiency Gasoline Engine · 1 Prof. Bengt Johansson Division of Combustion Engines. Department of Energy Sciences. Lund University. SI HCCI PPC. Path to High Efficiency

Outline

• HCCI and fuel efficiency– 50% thermal efficiency

• Partially premixed combustion, PPC– Background

– Why gasoline is the best diesel engine fuel

– 56% thermal efficiency in car size engine

– 57% thermal efficiency in truck size engine

– Why 55% thermal efficiency is better than 57%

– How to reach 26 bar IMEP with US10 NOx, PM, HC and CO engine out

19

Page 20: Path to High Efficiency Gasoline Engine · 1 Prof. Bengt Johansson Division of Combustion Engines. Department of Energy Sciences. Lund University. SI HCCI PPC. Path to High Efficiency

20

VOLVO D5 with Gasoline

-80 -60 -40 -20 0 20 400

50

100

150

CAD [TDC]

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

N 2000 [rpm]

IMEPg 13.38 [bar]

Pin 2.57 [bar]

Tin 354 [K]

EGR 39 [%]

lambda 1.75 [-]

Injection SOI [TDC] Fuel MEP [bar] Percentage [%]

1 -64.00 10.88 41.28

2 -29.20 7.74 29.36

3 0.80 7.74 29.36

Load NoiseLoad & CA50

Page 21: Path to High Efficiency Gasoline Engine · 1 Prof. Bengt Johansson Division of Combustion Engines. Department of Energy Sciences. Lund University. SI HCCI PPC. Path to High Efficiency

21

Efficiencies & Emissions

Indicated Gross Thermal Combustion/240

42

44

46

48

50

52

54

56

58

60

Effi

cien

cy [%

]

91 %

NOx*100 [g/kWh] CO [g/kWh] HC [g/kWh] Soot [FSN]0

5

10

15

20

25

30

35

40

Em

issi

ons

BelowDetectableLevel

13 ppm

0.46 %

4598 ppm

! D60 project goal

dPmax 7.20 [bar/CAD]

CA5 3.40 [TDC]

ID -1.00 [CAD]

CA50 11.35 [TDC]

CA90-10 13.00 [CAD]

Page 22: Path to High Efficiency Gasoline Engine · 1 Prof. Bengt Johansson Division of Combustion Engines. Department of Energy Sciences. Lund University. SI HCCI PPC. Path to High Efficiency

Burn rate and ηT

22

Optimum Thermodynamic efficiency

Premixedness

High heat losses

Low effective expansion ratio

-80 -60 -40 -20 0 20 400

50

100

150

CAD [TDC]

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

Page 23: Path to High Efficiency Gasoline Engine · 1 Prof. Bengt Johansson Division of Combustion Engines. Department of Energy Sciences. Lund University. SI HCCI PPC. Path to High Efficiency

Outline

• HCCI and fuel efficiency– 50% thermal efficiency

• Partially premixed combustion, PPC– Background

– Why gasoline is the best diesel engine fuel

– 56% thermal efficiency in car size engine

– 57% thermal efficiency in truck size engine

– Why 55% thermal efficiency is better than 57%

– How to reach 26 bar IMEP with US10 NOx, PM, HC and CO engine out

23

Page 24: Path to High Efficiency Gasoline Engine · 1 Prof. Bengt Johansson Division of Combustion Engines. Department of Energy Sciences. Lund University. SI HCCI PPC. Path to High Efficiency

242424

Experimental setup, Scania D12Bosch Common RailPrailmax 1600 [bar]

Orifices 8 [-]

Orifice Diameter 0.18 [mm]

Umbrella Angle 120 [deg]

Engine / Dyno SpecBMEPmax 15 [bar]

Vd 1951 [cm3]

Swirl ratio 2.9 [-]

Fuel: Gasoline or Ethanol

Page 25: Path to High Efficiency Gasoline Engine · 1 Prof. Bengt Johansson Division of Combustion Engines. Department of Energy Sciences. Lund University. SI HCCI PPC. Path to High Efficiency

2525

rc: 17.1:1rc: 14.3:1

Low Compression Ratio PPC High Compression Ratio PPC

Two Test Series: High & Low Compression Ratio

Page 26: Path to High Efficiency Gasoline Engine · 1 Prof. Bengt Johansson Division of Combustion Engines. Department of Energy Sciences. Lund University. SI HCCI PPC. Path to High Efficiency

26262626

Fuel amount in the pilot is a function of:1.rc2.RON/MON3.EGR

-60 -50 -40 -30 -20 -10 0 100

0.2

0.4

0.6

0.8

1

CAD [TDC]

[a.u

.]

Load & CA50Const.

It must not react during compression

Injection StrategyIt consists of two injections. The first one is placed @ -60 TDC to create a homogeneous mixture while the second around TDC. The stratification created by the second injection triggers the combustion. The first injection must not react during the compression stroke, this is achieved by using EGR.

SAE 2009-01-0944

Page 27: Path to High Efficiency Gasoline Engine · 1 Prof. Bengt Johansson Division of Combustion Engines. Department of Energy Sciences. Lund University. SI HCCI PPC. Path to High Efficiency

2727

IMEP sweep @ 1300 [rpm]EGR ~ const throughout the sweep, 40-50 [%]λ~ const throughout the sweep, 1.5-1.6 [-]Tin = 308 [K]

Standard piston bowl, rc: 17:1

High Compression Ratio PPC

SAE 2009-01-2668

Page 28: Path to High Efficiency Gasoline Engine · 1 Prof. Bengt Johansson Division of Combustion Engines. Department of Energy Sciences. Lund University. SI HCCI PPC. Path to High Efficiency

28

Running Conditions

4 5 6 7 8 9 10 11 12 131.5

1.75

2

2.25

2.5

Gross IMEP [bar]

[bar

]

4 5 6 7 8 9 10 11 12 130

50

100

150

200

250

300

350

[C]Inlet Pressure

Exhaust Pressure

Inlet TemperatureExhaust Temperature

4 5 6 7 8 9 10 11 12 131.2

1.3

1.4

1.5

1.6

1.7

1.8

1.9

2

Gross IMEP [bar]

λ [-]

4 5 6 7 8 9 10 11 12 1330

35

40

45

50

55

60

EG

R [%

]

Page 29: Path to High Efficiency Gasoline Engine · 1 Prof. Bengt Johansson Division of Combustion Engines. Department of Energy Sciences. Lund University. SI HCCI PPC. Path to High Efficiency

2929

Efficiencies

4 5 6 7 8 9 10 11 12 1350

55

60

65

70

75

80

85

90

95

100

Gross IMEP [bar]

[%] Combustion Efficiency

Thermal EfficiencyGas Exchange EfficiencyMechanical Efficiency

Page 30: Path to High Efficiency Gasoline Engine · 1 Prof. Bengt Johansson Division of Combustion Engines. Department of Energy Sciences. Lund University. SI HCCI PPC. Path to High Efficiency

3030

2 4 6 8 10 12 1430

35

40

45

50

55

60

Gross IMEP [bar]

[%]

Gross Ind. EfficiencyNet Ind. EfficiencyBrake Efficiency

Efficiency

57%

Too much heat transferToo much rate controlled combustion

Page 31: Path to High Efficiency Gasoline Engine · 1 Prof. Bengt Johansson Division of Combustion Engines. Department of Energy Sciences. Lund University. SI HCCI PPC. Path to High Efficiency

312 4 6 8 10 12 14

0

2

4

6

8

10

12

14

16

18

Gross IMEP [bar]

CO

[g/k

Wh]

GrossNetBrakeEU VIUS 10

2 4 6 8 10 12 140

0.5

1

1.5

2

2.5

3

3.5

4

4.5

5

Sm

oke

[FS

N]

Gross IMEP [bar]

312 4 6 8 10 12 14

0

0.5

1

1.5

2

2.5

3

3.5

4

4.5

5

Gross IMEP [bar]

HC

[g/k

Wh]

GrossNetBrakeEU VIUS 10

EmissionsObsolete injection system

Not well tuned EGR-λcombination

2 4 6 8 10 12 140

0.05

0.1

0.15

0.2

0.25

0.3

0.35

0.4

0.45

0.5

Gross IMEP [bar]

NO

x [g

/kW

h]

GrossNetBrakeEU VIUS 10

Page 32: Path to High Efficiency Gasoline Engine · 1 Prof. Bengt Johansson Division of Combustion Engines. Department of Energy Sciences. Lund University. SI HCCI PPC. Path to High Efficiency

Outline

• HCCI and fuel efficiency– 50% thermal efficiency

• Partially premixed combustion, PPC– Background

– Why gasoline is the best diesel engine fuel

– 56% thermal efficiency in car size engine

– 57% thermal efficiency in truck size engine

– Why 55% thermal efficiency is better than 57%

– How to reach 26 bar IMEP with US10 NOx, PM, HC and CO engine out

32

Page 33: Path to High Efficiency Gasoline Engine · 1 Prof. Bengt Johansson Division of Combustion Engines. Department of Energy Sciences. Lund University. SI HCCI PPC. Path to High Efficiency

3333

Low Compression Ratio PPC

IMEP sweep @ 1300 [rpm]EGR ~ const throughout the sweep, 40-50 [%]λ~ const throughout the sweep, 1.5-1.6 [-]Tin = 308 [K]

Custom piston bowl, rc: 14.3:1

SAE 2010-01-0871

Page 34: Path to High Efficiency Gasoline Engine · 1 Prof. Bengt Johansson Division of Combustion Engines. Department of Energy Sciences. Lund University. SI HCCI PPC. Path to High Efficiency

3434

4 6 8 10 12 14 16 1850

55

60

65

70

75

80

85

90

95

100

Gross IMEP [bar]

[%] Combustion Efficiency

Thermal EfficiencyGas Exchange EfficiencyMechanical Efficiency

Efficiencies

Page 35: Path to High Efficiency Gasoline Engine · 1 Prof. Bengt Johansson Division of Combustion Engines. Department of Energy Sciences. Lund University. SI HCCI PPC. Path to High Efficiency

3535

4 6 8 10 12 14 16 180

0.2

0.4

0.6

0.8

1

1.2

1.4

1.6

1.8

2

Sm

oke

[FS

N]

Gross IMEP [bar]2 4 6 8 10 12 14 16 18

0

0.1

0.2

0.3

0.4

0.5

0.6

Gross IMEP [bar]

NO

x [g

/kW

h]

GrossNetBrakeEU VIUS 10

2 4 6 8 10 12 14 16 180

1

2

3

4

5

6

7

8

9

10

Gross IMEP [bar]

CO

[g/k

Wh]

GrossNetBrakeEU VIUS 10

2 4 6 8 10 12 14 16 180

0.3

0.6

0.9

1.2

1.5

Gross IMEP [bar]

HC

[g/k

Wh]

GrossNetBrakeEU VIUS 10

Emissions

Better tuned EGR-λcombination

Page 36: Path to High Efficiency Gasoline Engine · 1 Prof. Bengt Johansson Division of Combustion Engines. Department of Energy Sciences. Lund University. SI HCCI PPC. Path to High Efficiency

36

Emissions – different fuels

2 4 6 8 10 12 14 16 18 200

0.5

1

1.5

2

2.5

Gross IMEP [bar]

Soo

t [F

SN

]

EthanolFR47330CVXFR47331CVXFR47333CVXFR47334CVXFR47335CVXFR47336CVXFR47338CVX

2 4 6 8 10 12 14 16 18 200

0.05

0.1

0.15

0.2

0.25

0.3

0.35

0.4

0.45

0.5

Gross IMEP [bar]

NO

x [g

/kW

h]

EthanolFR47330CVXFR47331CVXFR47333CVXFR47334CVXFR47335CVXFR47336CVXFR47338CVX

2 4 6 8 10 12 14 16 18 200

2

4

6

8

10

12

Gross IMEP [bar]

CO

[g/k

Wh]

EthanolFR47330CVXFR47331CVXFR47333CVXFR47334CVXFR47335CVXFR47336CVXFR47338CVX

2 4 6 8 10 12 14 16 18 200

1

2

3

4

5

6

7

8

9

10

Gross IMEP [bar]

HC

[g/k

Wh]

EthanolFR47330CVXFR47331CVXFR47333CVXFR47334CVXFR47335CVXFR47336CVXFR47338CVX

Page 37: Path to High Efficiency Gasoline Engine · 1 Prof. Bengt Johansson Division of Combustion Engines. Department of Energy Sciences. Lund University. SI HCCI PPC. Path to High Efficiency

Outline

• HCCI and fuel efficiency– 50% thermal efficiency

• Partially premixed combustion, PPC– Background

– Why gasoline is the best diesel engine fuel

– 56% thermal efficiency in car size engine

– 57% thermal efficiency in truck size engine

– Why 55% thermal efficiency is better than 57%

– How to reach 26 bar IMEP with US10 NOx, PM, HC and CO engine out

37

Page 38: Path to High Efficiency Gasoline Engine · 1 Prof. Bengt Johansson Division of Combustion Engines. Department of Energy Sciences. Lund University. SI HCCI PPC. Path to High Efficiency

3838

Experimental Apparatus, Scania D13XPI Common RailOrifices 8 [-]

Orifice Diameter 0.19 [mm]

Umbrella Angle 148 [deg]

Engine / Dyno SpecBMEPmax 25 [bar]

Vd 2124 [cm3]

Swirl ratio 2.095 [-]

Standard piston bowl, rc: 17.3:1

Page 39: Path to High Efficiency Gasoline Engine · 1 Prof. Bengt Johansson Division of Combustion Engines. Department of Energy Sciences. Lund University. SI HCCI PPC. Path to High Efficiency

3939

5 10 15 20 25 3020

25

30

35

40

45

50

55

60

Gross IMEP [bar]

[%]

η brakeη netη gross

Efficiency

50% brake efficiency seems viable!!!

Page 40: Path to High Efficiency Gasoline Engine · 1 Prof. Bengt Johansson Division of Combustion Engines. Department of Energy Sciences. Lund University. SI HCCI PPC. Path to High Efficiency

405 10 15 20 25 3040

50

60

70

80

90

100

Gross IMEP [bar]

[%]

η combustionη gas exchangeη thermalη mechanical

Efficiency

ηηηηη MechanicaleGasExchangmicThermodynaCombustionBrake⋅⋅⋅=

50% brake efficiency maximization of all intermediate efficiencies

Page 41: Path to High Efficiency Gasoline Engine · 1 Prof. Bengt Johansson Division of Combustion Engines. Department of Energy Sciences. Lund University. SI HCCI PPC. Path to High Efficiency

RoHR, Cylinder Pressure & Injection Signal

-60 -40 -20 0 20 40 600

50

100

150

200

250

CAD [TDC]

IMEPg: 5 [bar]

lambda: 1.57 [-]EGR: 42.66 [%]CA50: 9.71 [TDC]COV: 2.2 [%]eta comb: 94.16 [%]NOx: 0.108 [g/kWh]HC: 2.7 [g/kW]CO: 23 [g/kW]Soot: 0.0033 [FSN]

Abs Pin: 1.07 [bar]Abs Pex: 1.15 [bar]Tin: 308 [K]Tex: 521 [K]

RoHR/3 [J/CAD]Cylinder Pressure [bar]Injection Current [a.u.]

-60 -40 -20 0 20 40 600

50

100

150

200

250

CAD [TDC]

IMEPg: 26 [bar]

lambda: 1.32 [-]EGR: 47.98 [%]CA50: 13.9 [TDC]COV: 0.56 [%]eta comb: 99.89 [%]NOx: 0.264 [g/kWh]HC: 0.091 [g/kW]CO: 0.31 [g/kW]Soot: 0.26 [FSN]

Abs Pin: 3.64 [bar]Abs Pex: 4.01 [bar]Tin: 293 [K]Tex: 673 [K]

RoHR/3 [J/CAD]Cylinder Pressure [bar]Injection Current [a.u.]

-60 -40 -20 0 20 40 600

50

100

150

200

250

CAD [TDC]

IMEPg: 20 [bar]

lambda: 1.37 [-]EGR: 53.22 [%]CA50: 9.27 [TDC]COV: 0.7 [%]eta comb: 99.89 [%]NOx: 0.201 [g/kWh]HC: 0.082 [g/kW]CO: 0.31 [g/kW]Soot: 0.21 [FSN]

Abs Pin: 3.21 [bar]Abs Pex: 3.48 [bar]Tin: 293 [K]Tex: 606 [K]

RoHR/3 [J/CAD]Cylinder Pressure [bar]Injection Current [a.u.]

-60 -40 -20 0 20 40 600

50

100

150

200

250

CAD [TDC]

IMEPg: 16 [bar]

lambda: 1.36 [-]EGR: 46.69 [%]CA50: 7.6 [TDC]COV: 0.58 [%]eta comb: 99.82 [%]NOx: 0.281 [g/kWh]HC: 0.1 [g/kW]CO: 0.63 [g/kW]Soot: 0.31 [FSN]

Abs Pin: 2.35 [bar]Abs Pex: 2.88 [bar]Tin: 292 [K]Tex: 623 [K]

RoHR/3 [J/CAD]Cylinder Pressure [bar]Injection Current [a.u.]

-60 -40 -20 0 20 40 600

50

100

150

200

250

CAD [TDC]

IMEPg: 11 [bar]

lambda: 1.48 [-]EGR: 46.41 [%]CA50: 6.82 [TDC]COV: 1.2 [%]eta comb: 99.4 [%]NOx: 0.317 [g/kWh]HC: 0.22 [g/kW]CO: 2.6 [g/kW]Soot: 0.05 [FSN]

Abs Pin: 1.76 [bar]Abs Pex: 2.73 [bar]Tin: 291 [K]Tex: 612 [K]

RoHR/3 [J/CAD]Cylinder Pressure [bar]Injection Current [a.u.]

Page 42: Path to High Efficiency Gasoline Engine · 1 Prof. Bengt Johansson Division of Combustion Engines. Department of Energy Sciences. Lund University. SI HCCI PPC. Path to High Efficiency

RoHR, Cylinder Pressure & Injection Signal

-60 -40 -20 0 20 40 600

50

100

150

200

250

CAD [TDC]

IMEPg: 5 [bar]

lambda: 1.57 [-]EGR: 42.66 [%]CA50: 9.71 [TDC]COV: 2.2 [%]eta comb: 94.16 [%]NOx: 0.108 [g/kWh]HC: 2.7 [g/kW]CO: 23 [g/kW]Soot: 0.0033 [FSN]

Abs Pin: 1.07 [bar]Abs Pex: 1.15 [bar]Tin: 308 [K]Tex: 521 [K]

RoHR/3 [J/CAD]Cylinder Pressure [bar]Injection Current [a.u.]

Page 43: Path to High Efficiency Gasoline Engine · 1 Prof. Bengt Johansson Division of Combustion Engines. Department of Energy Sciences. Lund University. SI HCCI PPC. Path to High Efficiency

RoHR, Cylinder Pressure & Injection Signal

-60 -40 -20 0 20 40 600

50

100

150

200

250

CAD [TDC]

IMEPg: 11 [bar]

lambda: 1.48 [-]EGR: 46.41 [%]CA50: 6.82 [TDC]COV: 1.2 [%]eta comb: 99.4 [%]NOx: 0.317 [g/kWh]HC: 0.22 [g/kW]CO: 2.6 [g/kW]Soot: 0.05 [FSN]

Abs Pin: 1.76 [bar]Abs Pex: 2.73 [bar]Tin: 291 [K]Tex: 612 [K]

RoHR/3 [J/CAD]Cylinder Pressure [bar]Injection Current [a.u.]

Page 44: Path to High Efficiency Gasoline Engine · 1 Prof. Bengt Johansson Division of Combustion Engines. Department of Energy Sciences. Lund University. SI HCCI PPC. Path to High Efficiency

RoHR, Cylinder Pressure & Injection Signal

-60 -40 -20 0 20 40 600

50

100

150

200

250

CAD [TDC]

IMEPg: 16 [bar]

lambda: 1.36 [-]EGR: 46.69 [%]CA50: 7.6 [TDC]COV: 0.58 [%]eta comb: 99.82 [%]NOx: 0.281 [g/kWh]HC: 0.1 [g/kW]CO: 0.63 [g/kW]Soot: 0.31 [FSN]

Abs Pin: 2.35 [bar]Abs Pex: 2.88 [bar]Tin: 292 [K]Tex: 623 [K]

RoHR/3 [J/CAD]Cylinder Pressure [bar]Injection Current [a.u.]

Page 45: Path to High Efficiency Gasoline Engine · 1 Prof. Bengt Johansson Division of Combustion Engines. Department of Energy Sciences. Lund University. SI HCCI PPC. Path to High Efficiency

RoHR, Cylinder Pressure & Injection Signal

-60 -40 -20 0 20 40 600

50

100

150

200

250

CAD [TDC]

IMEPg: 20 [bar]

lambda: 1.37 [-]EGR: 53.22 [%]CA50: 9.27 [TDC]COV: 0.7 [%]eta comb: 99.89 [%]NOx: 0.201 [g/kWh]HC: 0.082 [g/kW]CO: 0.31 [g/kW]Soot: 0.21 [FSN]

Abs Pin: 3.21 [bar]Abs Pex: 3.48 [bar]Tin: 293 [K]Tex: 606 [K]

RoHR/3 [J/CAD]Cylinder Pressure [bar]Injection Current [a.u.]

Page 46: Path to High Efficiency Gasoline Engine · 1 Prof. Bengt Johansson Division of Combustion Engines. Department of Energy Sciences. Lund University. SI HCCI PPC. Path to High Efficiency

RoHR, Cylinder Pressure & Injection Signal

-60 -40 -20 0 20 40 600

50

100

150

200

250

CAD [TDC]

IMEPg: 26 [bar]

lambda: 1.32 [-]EGR: 47.98 [%]CA50: 13.9 [TDC]COV: 0.56 [%]eta comb: 99.89 [%]NOx: 0.264 [g/kWh]HC: 0.091 [g/kW]CO: 0.31 [g/kW]Soot: 0.26 [FSN]

Abs Pin: 3.64 [bar]Abs Pex: 4.01 [bar]Tin: 293 [K]Tex: 673 [K]

RoHR/3 [J/CAD]Cylinder Pressure [bar]Injection Current [a.u.]

Page 47: Path to High Efficiency Gasoline Engine · 1 Prof. Bengt Johansson Division of Combustion Engines. Department of Energy Sciences. Lund University. SI HCCI PPC. Path to High Efficiency

47

0 5 10 15 20 25 300

1

2

3

4

5

6

7

8

9

10

Gross IMEP [bar]

Rel

ativ

e M

axim

um P

ress

ure

Ris

e R

ate

[bar

/CA

D]

HD Engine Treshold

0 5 10 15 20 25 300

0.5

1

1.5

2

2.5

3

3.5

4

4.5

5

Gross IMEP [bar]C

OV

of I

ME

P [%

] HD Engine Treshold

Combustion Noise & Stability

Page 48: Path to High Efficiency Gasoline Engine · 1 Prof. Bengt Johansson Division of Combustion Engines. Department of Energy Sciences. Lund University. SI HCCI PPC. Path to High Efficiency

4848

5 10 15 20 25 300

0.05

0.1

0.15

0.2

0.25

0.3

0.35

0.4

0.45

0.5

Gross IMEP [bar]

Soo

t [F

SN

]

Emissions

0 5 10 15 20 25 300

0.2

0.4

0.6

0.8

1

1.2

1.4

1.6

1.8

2

Gross IMEP [bar]

Bra

ke H

C [g

/kW

h]

Brake HCUS 10EU VI

0 5 10 15 20 25 300

0.1

0.2

0.3

0.4

0.5

0.6

Gross IMEP [bar]

Bra

ke N

Ox

[g/k

Wh]

Brake NOxUS10EU VI

0 5 10 15 20 25 300

5

10

15

20

25

Gross IMEP [bar]

Bra

ke C

O [g

/kW

h]

Brake COUS 10EU VI

Page 49: Path to High Efficiency Gasoline Engine · 1 Prof. Bengt Johansson Division of Combustion Engines. Department of Energy Sciences. Lund University. SI HCCI PPC. Path to High Efficiency

49

Summary

Page 50: Path to High Efficiency Gasoline Engine · 1 Prof. Bengt Johansson Division of Combustion Engines. Department of Energy Sciences. Lund University. SI HCCI PPC. Path to High Efficiency

505050

0 5 10 15 20 25 3036

38

40

42

44

46

48

50

52

54

56

58

Gross IMEP [bar]

Bra

ke E

ffici

ency

[%]

D12 High rc, G. 80/75D12 Low rc, G. 69/66D13 Standard, G. 69/66

Brake Efficiency

Brake efficiency in the range of 48-50% seems to be viable between 12.5 and 26 bar gross IMEP.

Page 51: Path to High Efficiency Gasoline Engine · 1 Prof. Bengt Johansson Division of Combustion Engines. Department of Energy Sciences. Lund University. SI HCCI PPC. Path to High Efficiency

51

D13 Running on Diesel & Gasoline

5 10 15 20 25 3034

36

38

40

42

44

46

48

50

52

Gross IMEP [bar]

Bra

ke E

ffici

ency

[%]

D13 GasolineD13 Diesel

D13 Diesel was calibrated by Scania and the calibration was done to meet EU V legislation.

Average improvement of 16.6% points @ high load!!!

Page 52: Path to High Efficiency Gasoline Engine · 1 Prof. Bengt Johansson Division of Combustion Engines. Department of Energy Sciences. Lund University. SI HCCI PPC. Path to High Efficiency

5252520 5 10 15 20 25 30

0

0.5

1

1.5

2

2.5

3

3.5

4

Gross IMEP [bar]

Bra

ke S

peci

fic H

C [g

/kW

h]

D12 High rcD12 Low rcD13 StandardEU VIUS 10

0 5 10 15 20 25 300

5

10

15

20

25

30

35

Gross IMEP [bar]

Bra

ke S

peci

fic C

O [g

/kW

h]

D12 High rcD12 Low rcD13 StandardEU VIUS 10

0 5 10 15 20 25 300

0.05

0.1

0.15

0.2

0.25

0.3

0.35

0.4

0.45

0.5

0.55

0.6

Gross IMEP [bar]

Bra

ke S

peci

fic N

Ox

[g/k

Wh]

D12 High rcD12 Low rcD13 StandardEU VIUS 10

0 5 10 15 20 25 300

0.5

1

1.5

2

2.5

3

3.5

4

4.5

Gross IMEP [bar]

Soo

t [F

SN

]

D12 High rcD12 Low rcD13 Standard

Brake Emissions

Page 53: Path to High Efficiency Gasoline Engine · 1 Prof. Bengt Johansson Division of Combustion Engines. Department of Energy Sciences. Lund University. SI HCCI PPC. Path to High Efficiency

53

Engine combustion - direction

Spark Ignition (SI) engine (Gasoline,

Otto)

Compression Ignition (CI) engine

(Diesel)

Homogeneous Charge

Compression Ignition (HCCI)

Diesel PPC

+ High Efficiency

+ Ultralow NOx & soot

- Combustion control

- Power density

+ Clean with 3-way Catalyst

- Poor low & part load efficiency

+ High efficiency- Emissions of NOx

and soot

+ Injection controlled- Efficiency at high load

Gasoline PPC

+ High Efficiency+ Low NOx & soot

1900-1995

1995-2005

2005-2010

2010-

Page 54: Path to High Efficiency Gasoline Engine · 1 Prof. Bengt Johansson Division of Combustion Engines. Department of Energy Sciences. Lund University. SI HCCI PPC. Path to High Efficiency

The End

Thank you

54

Page 55: Path to High Efficiency Gasoline Engine · 1 Prof. Bengt Johansson Division of Combustion Engines. Department of Energy Sciences. Lund University. SI HCCI PPC. Path to High Efficiency

55

Prof. Bengt Johansson

Division of Combustion EnginesDepartment of Energy Sciences

Lund University

SI HCCI PPC

Path to High Efficiency Gasoline Engine

Page 56: Path to High Efficiency Gasoline Engine · 1 Prof. Bengt Johansson Division of Combustion Engines. Department of Energy Sciences. Lund University. SI HCCI PPC. Path to High Efficiency

Outline

• Partially premixed combustion, PPC– Summary of

• 56% thermal efficiency in car size engine

• 57% thermal efficiency in truck size engine

• Why 55% thermal efficiency is better than 57%

– Fuel effects in Scania D12 engine

– How to reach 26 bar IMEP with US10 NOx, PM, HC and CO engine out, Scania D13

– Fuel effects in Scania D13 engine

56

Page 57: Path to High Efficiency Gasoline Engine · 1 Prof. Bengt Johansson Division of Combustion Engines. Department of Energy Sciences. Lund University. SI HCCI PPC. Path to High Efficiency

575757

RON MON C H/C O/C LHV [MJ/kg] A/F stoichGroup 1 FR47335CVX 99.0 96.9 7.04 2.28 0.00 44.30 15.10

FR47332CVX 97.7 87.5 6.61 2.06 0.07 39.70 13.44

FR47337CVX 96.5 86.1 7.53 1.53 0.00 42.10 14.03

Group 2 FR47338CVX 88.6 79.5 7.21 1.88 0.00 43.50 14.53

FR47330CVX 87.1 80.5 7.20 1.92 0.00 43.50 14.60

FR47331CVX 92.9 84.7 6.90 1.99 0.03 41.60 14.02

Group 3 FR47336CVX 70.3 65.9 7.10 2.08 0.00 43.80 14.83

FR47334CVX 69.4 66.1 7.11 1.98 0.00 43.80 14.68

FR47333CVX 80.0 75.0 7.16 1.97 0.00 43.70 14.65

Group 4 PRF20 20 20 7.2 2.28 0 44.51 15.07

MK1 n.a. 20 16 1.87 0 43.15 14.9

Fuel Matrix

Page 58: Path to High Efficiency Gasoline Engine · 1 Prof. Bengt Johansson Division of Combustion Engines. Department of Energy Sciences. Lund University. SI HCCI PPC. Path to High Efficiency

585858

Results

Page 59: Path to High Efficiency Gasoline Engine · 1 Prof. Bengt Johansson Division of Combustion Engines. Department of Energy Sciences. Lund University. SI HCCI PPC. Path to High Efficiency

595959

20 30 40 50 60 70 80 90 1000

5

10

15

20

25

RON [-]

IME

P g

ross

[bar

]

Stable operational load vs. fuel type

Tested Load Area

Page 60: Path to High Efficiency Gasoline Engine · 1 Prof. Bengt Johansson Division of Combustion Engines. Department of Energy Sciences. Lund University. SI HCCI PPC. Path to High Efficiency

60606030 35 40 45 50 55 60 65 70

1000

1200

1400

1600

1800

2000

2200

2400Adiabatic Flame Temperature

EGR Ratio [%]

Tem

pera

ture

[K]

λ=1λ=1.1λ=1.2λ=1.3λ=1.4λ=1.5λ=1.6λ=1.7λ=1.8λ=2λ=2.5λ=3λ=3.5λ=4

HC/COF/A

EQ

UIV

ALE

NC

E R

ATIO

TEMPERATURE

NOx - ηcomb Trade – Off Solution

It is possible to achieve low NOx and still keep high combustion efficiency in the whole load range!

0 0.2 0.4 0.6 0.8 190

91

92

93

94

95

96

97

98

99

100

NOx [g/kWh]

Com

bust

ion

Effi

cien

cy [%

] G. ON 99/97G. ON 98/88G. ON 97/86G. ON 93/85G. ON 89/80G. ON 87/81G. ON 80/75G. ON 70/66G. ON 69/66PRF20

Page 61: Path to High Efficiency Gasoline Engine · 1 Prof. Bengt Johansson Division of Combustion Engines. Department of Energy Sciences. Lund University. SI HCCI PPC. Path to High Efficiency

616161

In certain operating range, some fuels are capable to comply EU VI & US10 legislations and still keep high

efficiency without compromising the efficiency!

Efficiency & Emissions

0 0.2 0.4 0.6 0.8 150

51

52

53

54

55

56

57

58

59

60

NOx [g/kWh]

Gro

ss In

dica

ted

Effi

cien

cy [%

]

G. ON 99/97G. ON 98/88G. ON 97/86G. ON 93/85G. ON 89/80G. ON 87/81G. ON 80/75G. ON 70/66G. ON 69/66PRF20

0 0.1 0.2 0.3 0.4 0.5 0.6 0.7 0.8 0.9 10

0.005

0.01

0.015

0.02

0.025

0.03

0.035

0.04

0.045

0.05

Indicated NOx [g/kWh]

Soo

t [g/

kWh]

G. ON 99/97G. ON 98/88G. ON 97/86G. ON 93/85G. ON 89/80G. ON 87/81G. ON 80/75G. ON 70/66G. ON 69/66D. CN 52PRF20EU VIUS10

Page 62: Path to High Efficiency Gasoline Engine · 1 Prof. Bengt Johansson Division of Combustion Engines. Department of Energy Sciences. Lund University. SI HCCI PPC. Path to High Efficiency

626262

Soot Emissions

0 5 10 15 20 25 300

0.5

1

1.5

2

2.5

3

Gross IMEP [bar]

Soo

t [F

SN

]G. ON 99/97G. ON 98/88G. ON 97/86G. ON 93/85G. ON 89/80G. ON 87/81G. ON 80/75G. ON 70/66G. ON 69/66D. CN 52PRF20

Diesel vs. Gasoline

Page 63: Path to High Efficiency Gasoline Engine · 1 Prof. Bengt Johansson Division of Combustion Engines. Department of Energy Sciences. Lund University. SI HCCI PPC. Path to High Efficiency

636363

Low soot even @ λ 1.3 higher power density without producing smoke!

Higher Power Density

1 1.1 1.2 1.3 1.4 1.50

0.5

1

1.5

2

2.5

3

λ [-]

Soo

t [F

SN

]

IMEPg: 20 & 25 [bar]

G. ON 99/97G. ON 98/88G. ON 97/86G. ON 93/85G. ON 89/80G. ON 87/81G. ON 80/75G. ON 70/66G. ON 69/66D. CN 52PRF20

Page 64: Path to High Efficiency Gasoline Engine · 1 Prof. Bengt Johansson Division of Combustion Engines. Department of Energy Sciences. Lund University. SI HCCI PPC. Path to High Efficiency

646464

Acoustic Noise

1 1.5 2 2.5 3 3.5 41

1.5

2

2.5

3

3.5

4

4.5

5

abs Inlet Pressure [bar]

Max

Pre

ssur

e R

ise

Rat

e [b

ar/C

AD

]

Motored Engine

MeasuredNormalized

0 5 10 15 20 25 301

3

5

7

9

11

13

15

Gross IMEP [bar]

Rel

ativ

e M

ax P

ress

ure

Ris

e R

ate

[bar

/CA

D]

G. ON 99/97G. ON 98/88G. ON 97/86G. ON 93/85G. ON 89/80G. ON 87/81G. ON 80/75G. ON 70/66G. ON 69/66D. CN 52PRF20Treshold

Page 65: Path to High Efficiency Gasoline Engine · 1 Prof. Bengt Johansson Division of Combustion Engines. Department of Energy Sciences. Lund University. SI HCCI PPC. Path to High Efficiency

656565

Idle

Page 66: Path to High Efficiency Gasoline Engine · 1 Prof. Bengt Johansson Division of Combustion Engines. Department of Energy Sciences. Lund University. SI HCCI PPC. Path to High Efficiency

666666

Efficiencies & Emissions

3 4 5 6 7 8 9 1030

32

34

36

38

40

42

44

46

48

50

Combustion Phasing [TDC]

[%]

3 4 5 6 7 8 9 1090

91

92

93

94

95

96

97

98

99

100

[%]

G. ON 69/66

Combustion Efficiency

Gross Indicated Efficiency [%]Thermal Efficiency [%]

3 4 5 6 7 8 9 100

0.05

0.1

0.15

0.2

0.25

0.3

0.35

0.4

Combustion Phasing [TDC]

NO

x / S

oot [

g/kW

h]

G. ON 69/66

3 4 5 6 7 8 9 100

5

10

15

20

25

30

35

40

45

50

CO

/ H

C [g

/kW

h]

NOxSoot

COHC

Page 67: Path to High Efficiency Gasoline Engine · 1 Prof. Bengt Johansson Division of Combustion Engines. Department of Energy Sciences. Lund University. SI HCCI PPC. Path to High Efficiency

67

Viability of Low ON Gasolines for PPC?

Page 68: Path to High Efficiency Gasoline Engine · 1 Prof. Bengt Johansson Division of Combustion Engines. Department of Energy Sciences. Lund University. SI HCCI PPC. Path to High Efficiency

686868Octane Number of the gasoline streams span from 99 to 50 RON Gasolines with 70 RON are already produced!!!

Oil Refineries Production Layout

90 < ON < 9950 < ON < 75

50%

20%

30%

Page 69: Path to High Efficiency Gasoline Engine · 1 Prof. Bengt Johansson Division of Combustion Engines. Department of Energy Sciences. Lund University. SI HCCI PPC. Path to High Efficiency

696969

Oil Refineries Perspectives

Oil refineries are a very stiff system and their kerosene, diesel and gasoline production can not be easily varied without major investments we need to build highly efficient vehicles with the available fuels…

Page 70: Path to High Efficiency Gasoline Engine · 1 Prof. Bengt Johansson Division of Combustion Engines. Department of Energy Sciences. Lund University. SI HCCI PPC. Path to High Efficiency

707070Page 70

20 30 40 50 60 70 80 90 1000

5

10

15

20

25

RON [-]

IME

P g

ross

[bar

]High ON Gasolines in Scania D13

What to do with these fuels?!

Still to be used in SI engines?!

Page 71: Path to High Efficiency Gasoline Engine · 1 Prof. Bengt Johansson Division of Combustion Engines. Department of Energy Sciences. Lund University. SI HCCI PPC. Path to High Efficiency

Minimum Turbo Efficiency

71

Page 72: Path to High Efficiency Gasoline Engine · 1 Prof. Bengt Johansson Division of Combustion Engines. Department of Energy Sciences. Lund University. SI HCCI PPC. Path to High Efficiency

Ideal burn rate?Conditions:

1. CA50: 8 [ATDC].

2. CA90-10: 15 [CAD].

3. Engine geometry: custom Scania D13.

4. Inlet temperature: 303 [K].

5. Reference temperature: 298 [K].

6. Engine speed: 1250 [rpm].

7. Differential pressure exhaust minus inlet: 0.25 [bar].

8. Cylinder wall temperature: 450 [K].

9. Heat transferred modeled with the Woschni equation and tuned to match the experimental results

10. The rate of heat release has been approximated with a Wiebe function.

11. EGR is added in order to have 1.35 as λ. If the inlet pressure was not enough to

have λ without EGR higher than 1.35, EGR was set to zero.

12. The combustion efficiency was assumed to be 100%.

13. Lower heating value 43.8 MJ/kg, stoichiometric air fuel ratio 14.68.

72

Page 73: Path to High Efficiency Gasoline Engine · 1 Prof. Bengt Johansson Division of Combustion Engines. Department of Energy Sciences. Lund University. SI HCCI PPC. Path to High Efficiency

Exhaust Loss

73

Page 74: Path to High Efficiency Gasoline Engine · 1 Prof. Bengt Johansson Division of Combustion Engines. Department of Energy Sciences. Lund University. SI HCCI PPC. Path to High Efficiency

Heat transfer loss

74

Page 75: Path to High Efficiency Gasoline Engine · 1 Prof. Bengt Johansson Division of Combustion Engines. Department of Energy Sciences. Lund University. SI HCCI PPC. Path to High Efficiency

The rest (useful work)

75

Page 76: Path to High Efficiency Gasoline Engine · 1 Prof. Bengt Johansson Division of Combustion Engines. Department of Energy Sciences. Lund University. SI HCCI PPC. Path to High Efficiency

Boosting reduce heat losses

76

Page 77: Path to High Efficiency Gasoline Engine · 1 Prof. Bengt Johansson Division of Combustion Engines. Department of Energy Sciences. Lund University. SI HCCI PPC. Path to High Efficiency

A-B-C of Fuel Consumption

A. Car size

B. Engine size

C. Engine efficiency in right operating conditions

77

Page 78: Path to High Efficiency Gasoline Engine · 1 Prof. Bengt Johansson Division of Combustion Engines. Department of Energy Sciences. Lund University. SI HCCI PPC. Path to High Efficiency

Porsche 911 performance with 100+ mpg?

78

• Two persons

• 100 liter of storage capacity

Page 79: Path to High Efficiency Gasoline Engine · 1 Prof. Bengt Johansson Division of Combustion Engines. Department of Energy Sciences. Lund University. SI HCCI PPC. Path to High Efficiency

Porsche 911 data

79

M=1550 kgCr=0.012Av=1.96 m2Cd=0.33

Vd=3.8 literP=355 PS (hp)T=400 Nm

Performance 0-60: 4.6 sV,max=300 km/h ( 186.5 mph)Fuel consump.= 12.0 l/100 km (19.6 mpg)

Page 80: Path to High Efficiency Gasoline Engine · 1 Prof. Bengt Johansson Division of Combustion Engines. Department of Energy Sciences. Lund University. SI HCCI PPC. Path to High Efficiency

Power needed @300 km/h (186.5 mph)

80

( )

hpkW

xxxxxxx

vvACmgCP vDaR

1.3268.239

6.3300

6.330096.133.02.15.081.91550012.0

5.02

2

==

+

=+= ρ

Page 81: Path to High Efficiency Gasoline Engine · 1 Prof. Bengt Johansson Division of Combustion Engines. Department of Energy Sciences. Lund University. SI HCCI PPC. Path to High Efficiency

The ”Cigar”

Page 82: Path to High Efficiency Gasoline Engine · 1 Prof. Bengt Johansson Division of Combustion Engines. Department of Energy Sciences. Lund University. SI HCCI PPC. Path to High Efficiency

Two person capacity is often enough

82

UK National Office of Statistics:“The average car occupancy is 1.6 people per car and for commuting it's 1.2 “

A carpool in California is a car with ONE person if the car is fuelefficient…

Page 83: Path to High Efficiency Gasoline Engine · 1 Prof. Bengt Johansson Division of Combustion Engines. Department of Energy Sciences. Lund University. SI HCCI PPC. Path to High Efficiency

The ”Cigar”

http://www.peraves.ch/

Existing large model use large BMW 1200 cc MC engine. With turbo a top speed of 315 km/h and fuel consumption of 3.5 l/100 km (67 mpg)

Page 84: Path to High Efficiency Gasoline Engine · 1 Prof. Bengt Johansson Division of Combustion Engines. Department of Energy Sciences. Lund University. SI HCCI PPC. Path to High Efficiency

Power needed @300 km/h (186.5 mph)

84

( )

hpkW

xxxxxxx

vvACmgCP vDaR

7.492.37

6.3300

6.33000.110.02.15.081.9250012.0

5.02

2

==

+

=+= ρ

Cigar design specificationsCd=0.1Av=0.5-1 m2

m= 250 kgCr=0.012 (two wheels)

Page 85: Path to High Efficiency Gasoline Engine · 1 Prof. Bengt Johansson Division of Combustion Engines. Department of Energy Sciences. Lund University. SI HCCI PPC. Path to High Efficiency

Power needed at 50 and 100 km/h (31- 62 mph)

Porsche 911 vs. cigar

85

Speed (km/h) 911 Cigar Unit Ratio50 3.57 0.57 kW 6.28100 13.4 2.1 kW 6.36300 239.8 37.2 kW 6.45

50 4.86 0.77 hp 6.28100 18.2 2.9 hp 6.36300 326.1 49.7 hp 6.45

Acceleration proportional to power/mass ratio:Cigar: 250/49.7=5.03 kg/hp911: 1550/355=4.37 kg/hp

Page 86: Path to High Efficiency Gasoline Engine · 1 Prof. Bengt Johansson Division of Combustion Engines. Department of Energy Sciences. Lund University. SI HCCI PPC. Path to High Efficiency

A. Car size • With more correct car size the engine size can

be reduced a factor of 6 i.e. single cylinder version of 911 engine with 633 cc displacement is enough

• Porsche 911 has a fuel consumption of 12 l/100 km (19.6 mpg)

• Cigar would have 12/6=2 l/100 km (117.6 mpg) without any need of new engine technology. (Scaling both engine and car size)

86

Page 87: Path to High Efficiency Gasoline Engine · 1 Prof. Bengt Johansson Division of Combustion Engines. Department of Energy Sciences. Lund University. SI HCCI PPC. Path to High Efficiency

0 20 40 60 80 100 120 140 160 180 200 220Bilhast. [km/h]

B. Engine size• A Porsche 911 does not operate at optimum

load points in normal driving.

• At 50 km/h the estimated load is only 2 bar BMEP or less

• Bsfc=400 g/kWh

(ηb=21 %)

87

Page 88: Path to High Efficiency Gasoline Engine · 1 Prof. Bengt Johansson Division of Combustion Engines. Department of Energy Sciences. Lund University. SI HCCI PPC. Path to High Efficiency

Engine downsizingThree options

1. Turbo or supercharge a small engine

2. Cylinder deactivation of large engine

3. Variable displacement i.e. variable engine size

88

Page 89: Path to High Efficiency Gasoline Engine · 1 Prof. Bengt Johansson Division of Combustion Engines. Department of Energy Sciences. Lund University. SI HCCI PPC. Path to High Efficiency

B.1. Mercedes CDI 250, 2.1 liter

89

Vd=2143 ccTorque= 500 Nm (369 lb-ft)

Page 90: Path to High Efficiency Gasoline Engine · 1 Prof. Bengt Johansson Division of Combustion Engines. Department of Energy Sciences. Lund University. SI HCCI PPC. Path to High Efficiency

90

Two stage turbo

Page 91: Path to High Efficiency Gasoline Engine · 1 Prof. Bengt Johansson Division of Combustion Engines. Department of Energy Sciences. Lund University. SI HCCI PPC. Path to High Efficiency

Engine downsizing- MB 250 CDI

91

Displacement of 2.1 liter giving 224 hp and 500 Nm of torque : 30 bar BMEP is now full load NOT 10 or 20 barFuel consumption;C-class 5.1 l/100 km (46.1 mpg), E-class 5.3 l/100 km (44.4 mpg),S-class 5.9 l/100 km (39.9 mpg)

CO2:C-class 139 g/kmE-class 143 g/kmS-class 155 g/km

Page 92: Path to High Efficiency Gasoline Engine · 1 Prof. Bengt Johansson Division of Combustion Engines. Department of Energy Sciences. Lund University. SI HCCI PPC. Path to High Efficiency

B2: Dual engine concept

• Use one small and one large engine

• As an example:– One 2 cylinder 1 liter engine

– One 4 cylinder 2 liter engine

• This gives us 1, 2 or 3 liter to choose from

92

Page 93: Path to High Efficiency Gasoline Engine · 1 Prof. Bengt Johansson Division of Combustion Engines. Department of Energy Sciences. Lund University. SI HCCI PPC. Path to High Efficiency

Layout 4 +2 cyl

FAS

Transm.

93

Fiat 2-cylinder production engine

Page 94: Path to High Efficiency Gasoline Engine · 1 Prof. Bengt Johansson Division of Combustion Engines. Department of Energy Sciences. Lund University. SI HCCI PPC. Path to High Efficiency

Operation• 2-cyl at low loads• 4-cyl operation at higher load operation

(Autobahn)• 6-cyl operation at highest loads• 6-cyl + FAS at transients

(with FAS start of 4-cyl)• FAS for regenerative braking• FAS for lowest speed operation ( < 5 km/h)• Manual selection should be possible

94

Page 95: Path to High Efficiency Gasoline Engine · 1 Prof. Bengt Johansson Division of Combustion Engines. Department of Energy Sciences. Lund University. SI HCCI PPC. Path to High Efficiency

B3: Variable displacement engine

• If we can change displacement, Vd, engine load, P, can be controlled without reducing BMEP!

95

td n

NVbmepP =

Page 96: Path to High Efficiency Gasoline Engine · 1 Prof. Bengt Johansson Division of Combustion Engines. Department of Energy Sciences. Lund University. SI HCCI PPC. Path to High Efficiency

Atkinson Cycle

96

Displacement from 0.15 to 0.85 l per cylinder gives 0.6 to 3.4 l four cylinder engine at full load (@max BMEP)

Page 97: Path to High Efficiency Gasoline Engine · 1 Prof. Bengt Johansson Division of Combustion Engines. Department of Energy Sciences. Lund University. SI HCCI PPC. Path to High Efficiency

Atkinson engine with variable displacement

97

Page 98: Path to High Efficiency Gasoline Engine · 1 Prof. Bengt Johansson Division of Combustion Engines. Department of Energy Sciences. Lund University. SI HCCI PPC. Path to High Efficiency

Atkinson engine efficiency

98

Page 99: Path to High Efficiency Gasoline Engine · 1 Prof. Bengt Johansson Division of Combustion Engines. Department of Energy Sciences. Lund University. SI HCCI PPC. Path to High Efficiency

Atkinson engine thermal efficiency

99

Page 100: Path to High Efficiency Gasoline Engine · 1 Prof. Bengt Johansson Division of Combustion Engines. Department of Energy Sciences. Lund University. SI HCCI PPC. Path to High Efficiency

A-B-C of Fuel Consumption

A. Car size

B. Engine size

C. Engine efficiency in right operating conditions(Maximum engine efficiency)

100

Page 101: Path to High Efficiency Gasoline Engine · 1 Prof. Bengt Johansson Division of Combustion Engines. Department of Energy Sciences. Lund University. SI HCCI PPC. Path to High Efficiency

Summary /ABC of fuel consumption

A. Correct car size gives factor of 6 in fuel consumption

B. Correct load point gives factor 2 in fuel consumption (21%-42% or 400-200 g/kWh)

C. Partially Premixed Combustion have the potential to extend brake efficiency to 50% with US10/Euro emissions. With further optimization 55% could be reached

D. With waste heat recovery 60% should be possible giving a factor of 3 from today.

A total reduction potential of factor 18!

101

Page 102: Path to High Efficiency Gasoline Engine · 1 Prof. Bengt Johansson Division of Combustion Engines. Department of Energy Sciences. Lund University. SI HCCI PPC. Path to High Efficiency

Cars and traffic situation

102