Effects of Pilot Injection Strategies on Spray Visualization and...

Smart Powertrain Lab.

Effects of Pilot Injection Strategies

on Spray Visualization and Combustion

in a Direct Injection

Compression Ignition Engine

using DME and Diesel

Jaehoon Jeong · SeJun Lee · Ocktaeck Lim University of Ulsan

7th Asian DME Conference

16 -18 November, 2011

Toki Messe Niigata Convention Center, Niigata, Japan


▌INTRODUCTION

Contents

▌OBJECTIVES

▌EXPERIMENTAL SETUP

▪ Spray Experimental System

▪ Engine Experiment System

▌CONCLUSION

▌RESULTS

▪ Spray Experiment

▪ Engine Experiment


▌INTRODUCTION

Contents

▌OBJECTIVES




▌CONCLUSION

▌RESULTS




DME Engine Characteristics

▪ Equal dynamic characteristic of diesel engine “The Experimental Study of Emission Characteristics and Fuel Efficiency for the Heavy-Duty DME Bus”, KSAE, submitted, 2011

▪ Almost Smoke-less Combustion “Improvement of Performance and Emission Gas Level of Dimethyl-Ether-Fueled Diesel Engine”, JSAE, 2005

▪ Improving the exhaust characteristic without after-treatment system “Potential of Fuel Stratification for Reducing Pressure Rise Rate in HCCI Engines fueled with DME/n-Butane”

▪ Good mixture formation & No wall wetting

▌Advantages

▌Disadvantages ▪ Low the fuel efficiency “Development of a Heavy-Duty DME Truck in EFV21 Project~Research and Development of DME Engine and Chassis”,SAE

paper 2005-03-0176, 2005

▪ Potential for high NOx emissions “Development of NOx storage reduction system for a dimethyl ether engine”,SAE paper 2004-01-1832, 2004

▪ Small low heating value compared to the diesel “The Performance of a Diesel Engine for Light Duty Truck Using a Jerk Type, In-Line DME Injection System”, SAE paper 2004-

01-1862, 2004





▪ Good mixture formation & No wall wetting

▌Advantages


paper 2005-03-0176, 2005



01-1862, 2004


- Inner boundary of diffusion flame

: High temperature in combination with less available oxygen

Using DME fuel for smoke reduction : H. Teng and G. Regner, “Fuel Injection Strategy for Reducing NOx Emissions from Haevy-Duty Diesel Engines Fueled with DME”,

SAE 2006-01-3324, 2006

▌Smoke formation in CI engine

▌NOx formation in CI engine

- Premixed combustion / Outer boundary of diffusion flame

: Sudden combustion of over premixed fuel-air mixture with

high temperature

Applying Pilot–Main injection strategy for NOx reduction : K. Okude, K. Mori, S. Shiino, K. Yamada and Y. Matsumoto, “Effects of Multiple Injections on Diesel Emissions and

Combustion Characteristics”, SAE 2007-01-4178, 2007

▌Need more DME injection quantity

: Due to small low heating value than diesel

Enlargement of nozzle holes diameter

: Mitsuru Konno, Kazuki Chiba, and Takeshi Okamoto, “Experimental and Numerical Analysis of High Pressure DME Spray”, SAE,

2010-01-0880, 2010






SAE 2006-01-3324, 2006





high temperature

Applying Pilot–Main injection strategy for NOx reduction : K. Okude, K. Mori, S. Shiino, K. Yamada and Y. Matsumoto, “Effects of Multiple Injections on Diesel Emissions and

Combustion Characteristics”, SAE 2007-01-4178, 2007

▌Need more DME injection quantity

: Due to small low heating value than diesel

Enlargement of nozzle holes diameter

: Mitsuru Konno, Kazuki Chiba, and Takeshi Okamoto, “Experimental and Numerical Analysis of High Pressure DME Spray”, SAE,

2010-01-0880, 2010



▌INTRODUCTION

Contents

▌OBJECTIVES




▌CONCLUSION

▌RESULTS




Objectives

▌Engine Experiment

: To apply Pilot-Main injection strategy using DME for

low NOx and high power in CI engine

▌Spray Experiment : To perform the spray experiments by the increase of

nozzle hole diameter for solve DME`s small low heating value

▪ Parameter

- Nozzle hole diameter

▪ Analysis

- Injection quantity

- Penetration lenth

- BMEP

- Spray angle

▪ Parameter

- Dwell time between main injection and pilot injection

- Main injection timing retard

▪ Acquisition of Data

- Cylinder Combustion Pressure

- Torque

- Exhaust Gas (CO,THC,NOx and Smoke)

▪ Analysis

- Curve of Combustion Pressure

- Heat Release Rate

- Emissions Characteristic


▌INTRODUCTION

Contents

▌OBJECTIVES




▌CONCLUSION

▌RESULTS




Injector

Strobe Light

Accumulator

Air Pump

Accumulator

Relief Valve

Common Rail

Check ValveReturn Line

Compressor

Air

PCVDriverDME

Low Pressure Pump

RefrigerantCompressor

Cooling Fan PressureSensor

N2

PulseGenerator

Common Rail Solenoid Injector

Peak & Hold Driver

InjectorDriver

Computer

Camera

High Pressure Chamber

Charge

Amplifier

Fuel QuantityMeasuring

Device

DME High Pressure Line

DME Low Pressure Line

Signal Line

Air, N2 Line

Fuel Quantity

Measuring Device

Spray Visualization

System

Spray Experiment System

Chamber

N2

D M E

DME Injection System


DME Diesel

Common-rail ▪ The 2nd generation of Common-rail (Bosch)

Injector ▪ Common-rail solenoid injector from (Bosch)

Low pressure pump Pressurized by N2 Vane-type pump

High pressure pump Air driven liquid pump (Haskel) Radial piston pump (Bosch)

DME Diesel





N2

DME

Pressurization

≈ 15 bar Fuel

outlet

(Liquid)

N2

N2

Fuel

inlet

Fuel

outlet

Vane

DME Diesel





Air drive

inlet

Air drive

outlet

Fuel

outlet

Fuel

inlet

Piston

Fuel

inlet

Fuel

outlet

Fuel Injection System

▌Fuel Injection Systems for DME and Diesel


Φ = 0.166

[ Diesel ]

Φ = 0.300

[ DME ]

Production by Delphi

Nozzle type VCO

The number of nozzle hole 6

Diameter of nozzle hole [mm] 0.166 0.300

Spray angle [deg] 140

Test injector

VOC Type


Property DME Diesel

Chemical structure CH3OCH3 CnH1.8n

Auto-ignition temperature [℃] 235 250

Oxygen content [wt %] 34.8 0

Boiling point [℃, 1atm] -25.1 180 - 370

Liquid density [kg/m3, 20℃, 2MPa] 668 824

Vapor pressure [MPa, 20℃] 0.51 -

Cetane number 55 - 60 40 – 55

Lower calorific value [MJ/Kg] 27.6 42.5

※ Adding Bio-diesel aobut 1% for lubrication

Dimethyl-Ether, DME

▌Physical properties of DME and Diesel


▌INTRODUCTION

Contents

▌OBJECTIVES




▌CONCLUSION

▌RESULTS




Engine type Water-cooled 4 cycle diesel

Number of cylinder 1

Bore×Stroke 83×92 mm

Displacement 498 cm3

Number of valves 2 intake, 2 exhaust

Compression ratio 19.5

Valve timing Intake 8 oCA bTDC / 44 oCA aBDC

Exhaust 54.6 oCA bTDC / 7.4 oCA aTDC

Fuel injection system Common-rail

Injection type Direct injection

Nozzle holes 7 holes

Nozzle hole diameter 0.141mm

Research Engine


Intake

Plenum Exhaust

plenum

EC

Dynamometer

Encoder

Laminar flow

meter

Air in

To Stack

Common-rail

Pressure Control

Driver

Engine

Controller

Injector

Driver

Encoder

Interfacing Box

Air

filter

Air

Heater

DP

sensor

Smoke

Meter

(AVL 415

smoke meter)

Common-rail


for DME injection

DME Testing

Exhaust -Gas

Analyzers

(Horiba

MEXA-7100

DEGR)

CO

HC

NOx

Common-rail


for Diesel injection

Diesel Testing

Schematic of Engine Facility


▌INTRODUCTION

Contents

▌OBJECTIVES




▌CONCLUSION

▌RESULTS




DME Diesel

Injector diameter Φ = 0.300 mm Φ = 0.166 mm

Injection pressure 700 bar

Ambient pressure 55 bar

Injection duration 1ms

The number of injection 1000 times

Experimental Condition of Spray

▌Experimental Condition of Spray


Injection Quantity

1

1.2

1.4

1.6

1.8

Inje

cti

on

Qu

an

tity

[k

J/c

yc

le]

Diesel_Pamb5.5MPa_0.166 mm

DME_Pamb5.5MPa_0.300 mm

0.03

0.05

0.07

0.09

Inje

ctio

n Q

ua

ntity

[ml/c

yc

le]

Injection Pressure[bar]

300 350 400 450 500 550 600 650 700 750

▌Injection Quantity

Pinject = 700 bar

Po = 55 bar (by N2)

To = 25 ± 1 ℃

DME, Φ = 0.300 mm

Diesel, Φ = 0.166 mm


▌Diesel Spray Shape [ΦInjector = 0.166 mm]

Spray Shape

Fuel = Diesel

ΦInjector = 0.166 mm

Pinject = 700 bar

Po = 55 bar (by N2)

To = 25 ± 1 ℃


Spray Shape

▌DME Spray Shape [ΦInjector = 0.300 mm]

Fuel = DME


Pinject = 700 bar

Po = 55 bar (by N2)

To = 25 ± 1 ℃


0.1ms 0.4ms 0.7ms 1.0ms 1.3ms 1.6ms 1.9ms 2.2ms 2.5ms

▌Diesel Spray Shape [ΦInjector = 0.166 mm]

Spray Shape

Fuel = Diesel


Pinject = 700 bar

Po = 55 bar (by N2)

To = 25 ± 1 ℃

▌DME Spray Shape [ΦInjector = 0.300 mm] Fuel = DME


Pinject = 700 bar

Po = 55 bar (by N2)

To = 25 ± 1 ℃

0.1ms 0.4ms 0.7ms 1.0ms 1.3ms 1.6ms 1.9ms 2.2ms 2.5ms


Spray Shape

▌Spray Length

0

10

20

30

40

50

60

70

80

Pe

ne

tra

tio

n L

en

gth

[m

m]

0 0.5 1 1.5 2 2.5 3After Start of Injection [ms]

Diesel_0.166 mm_70 MPa

DME_0.300 mm_70 MPa

0

10

20

30

40

50

60

70

80

Sp

ray

An

gle

[d

eg

ree]

0 0.5 1 1.5 2 2.5 3After Start of Injection [ms]

Diesel_0.166 mm_70 MPa

DME_0.300 mm_70 MPa

▌Spray Angle

Pinject = 700 bar

Po = 55 bar (by N2)

To = 25 ± 1 ℃

DME, Φ = 0.300 mm

Diesel, Φ = 0.166 mm


▌INTRODUCTION

Contents

▌OBJECTIVES




▌CONCLUSION

▌RESULTS




Operating Condition

▌Operating Condition

Engine speed 1200 rpm

Intake air temperature 80 ℃±2

Coolant temperature 25 ℃±1

Fuel injection pressure 700 bar

Injection Pilot-Main injection

Test fuel DME (with biodiesel 1% for lubricity additive)

Diesel


DME

quantity

Diesel

quantity Input calories

Single 46 mm3 31 mm3 1.31 kJ/cycle

2-Stage

Pilot 5.7 mm3

(1/8)

4 mm3

(1/8) 0.16 kJ/cycle

Main 40.3 mm3

(7/8)

27 mm3

(7/8) 1.15 kJ/cycle

Injection Strategy



▌ Injection Timing

Single dSOI 0 oCA

Main -4, -2, 0, 2, 4 oCA aTDC

2-Stage dSOI 10, 16, 22 oCA

Main -4, -2, 0, 2, 4 oCA aTDC

1.15 kJ/cycle

(7/8)

0.16 KJ/Cycle

(1/8)

dSOI : 22oCA

Injection Strategy

1.31 kJ/cycle

(8/8)

dSOI : 0oCA

[ Single injection ]

1.15 kJ/cycle

(7/8)

0.16 kJ/cycle

(1/8)

dSOI : 16oCA

1.15 kJ/cycle

(7/8)

0.16 KJ/Cycle

(1/8)

dSOI : 10oCA


▌Cylinder Pressure & HRR [ SOImain: -4 oCA aTDC ]

①

① Single Injection

① Ignition delay

: 8.8 oCA

Pilot-main Injection

① Ignition delay

: 6.6 oCA

SOI main : -4 oCA aTDC

Speed = 1200 rpm

Pinjection = 700 bar

Pin,air = 1 bar

Tin,water = 80 ± 1 ℃

Tin,air = 25 ± 2 ℃

Qin = 1.31 kJ/cycle

DME

Combustion Characteristic


Speed = 1200 rpm


Pin,air = 1 bar


Tin,air = 25 ± 2 ℃

Qin = 1.31 kJ/cycle

▌BMEP / NOx

Emission Characteristic

Diesel

DME

Single injection

dSOI: 22oCA

dSOI: 16oCA dSOI: 10oCA


Speed = 1200 rpm


Pin,air = 1 bar


Tin,air = 25 ± 2 ℃

Qin = 1.31 kJ/cycle

▌Smoke / NOx


Diesel

DME


▌CO+THC / NOx


Speed = 1200 rpm


Pin,air = 1 bar


Tin,air = 25 ± 2 ℃

Qin = 1.31 kJ/cycle

Diesel

DME


▌INTRODUCTION

Contents

▌OBJECTIVES




▌CONCLUSION

▌RESULTS




Conclusion

▌Spray Experiment

▌Engine Experiment

▪ Investigation of DME low heat value problem by increasing

the nozzle holes diameter.

▪ spray of DME and diesel is roughly similar after 1ms

▪BMEP of pilot injection is increase than single injection.

So, Pilot injection is more effective to increase the BMEP in

DME injection than diesel injection.

▪ Lead to low NOx emissions due to the pilot injection

▪ Lower CO and THC emissions than diesel injection and DME

combustion is smokeless


Thank you for listening.


APPENDIX


BMEP

▌Diesel injection VS Pilot-main injection

4 10 16 22Dwell time between pilot & main injections [oCA]

460

480

500

520

540

560

580

600

620

640

BM

EP

[kP

a]

SOIMain: -4 oCA aTDC (Diesel)

SOIMain: -4 oCA aTDC (DME)



SOIMain: 0 oCA aTDC (Diesel)

SOIMain: 0 oCA aTDC (DME)





0 Single injection


NOx


700

800

900

1000

1100

1200

1300

1400

1500

1600

1700

1800

NO

x[p

pm

]











0


Single injection


CO


0

50

100

150

200

250

300

350

400

CO

[pp

m]











0


Single injection


THC


0

50

100

150

200

250

300

350

TH

C[p

pm

]











0


Single injection


Smoke

0


Single injection


340 345 350 355 360 365 370 375 380 385 390Crank Angle [oCA aTDC]

0

30

60

90

120

150

180

Heat-

Rele

ase

Rate

[J/oC

A]

0

30

60

90

120

150

180

Heat-

Rele

ase

Rate

[J/oC

A]

- 4 oCA aTDC

dSOI: 0 oCA

dSOI: 10 oCA

dSOI: 16 oCA

dSOI: 22 oCA

Diesel

Heat-release rates (356oCA)

▌A comparison of heat-release rates in diesel & DME

DME



0

30

60

90

120

150

180

Heat-

Rele

ase

Rate

[J/oC

A]0

30

60

90

120

150

180

Heat-

Rele

ase

Rate

[J/o

CA

]

-2 oCA aTDC

dSOI: 0 oCA

dSOI: 10 oCA

dSOI: 16 oCA

dSOI: 22 oCA

Diesel

DME





0

30

60

90

120

150

180

Heat-

Rele

ase

Rate

[J/oC

A]

0

30

60

90

120

150

180

Heat-

Rele

ase

Rate

[J/o

CA

]

0 oCA aTDC

dSOI: 0 oCA

dSOI: 10 oCA

dSOI: 16 oCA

dSOI: 22 oCA

Diesel

DME





0

30

60

90

120

150

180

Heat-

Rele

ase

Rate

[J/oC

A]0

30

60

90

120

150

180

Heat-

Rele

ase

Rate

[J/o

CA

]

2 oCA aTDC

dSOI: 0 oCA

dSOI: 10 oCA

dSOI: 16 oCA

dSOI: 22 oCA

Diesel

DME




0

30

60

90

120

150

180

Heat-

Rele

ase

Rate

[J/o

CA

]

4 oCA aTDC

dSOI: 0 oCA

dSOI: 10 oCA

dSOI: 16 oCA

dSOI: 22 oCA


0

30

60

90

120

150

180

Heat-

Rele

ase

Rate

[J/oC

A]

Diesel



DME



203040

506070

8090

100

Cylin

der

Pre

ssu

re[b

ar]

20

304050

607080

90100

Cylin

der

Pre

ssu

re[b

ar]

- 4 oCA aTDC

dSOI: 0 oCA

dSOI: 10 oCA

dSOI: 16 oCA

dSOI: 22 oCA

Diesel

DME

Pressure traces (356oCA)



20

3040

506070

8090

100

Cylin

der

Pre

ssu

re[b

ar]

20

304050

6070

8090

100

Cylin

der

Pre

ssu

re[b

ar]

-2 oCA aTDC

dSOI: 0 oCA

dSOI: 10 oCA

dSOI: 16 oCA

dSOI: 22 oCA

Diesel

DME




20

3040

506070

8090

100

Cylin

der

Pre

ssu

re[b

ar]

20

304050

607080

90100

Cylin

der

Pre

ssu

re[b

ar]

0 oCA aTDC

dSOI: 0 oCA

dSOI: 10 oCA

dSOI: 16 oCA

dSOI: 22 oCA

Diesel

DME



20

304050

607080

90100

Cylin

der

Pre

ssu

re[b

ar]

2 oCA aTDC

dSOI: 0 oCA

dSOI: 10 oCA

dSOI: 16 oCA

dSOI: 22 oCA


20

30

40

50

60

70

80

90

Cylin

der

Pre

ssu

re[b

ar]

Diesel

DME




203040

506070

8090

100

Cylin

der

Pre

ssu

re[b

ar]

20

304050

607080

90100

Cylin

der

Pre

ssu

re[b

ar]

4 oCA aTDC

dSOI: 0 oCA

dSOI: 10 oCA

dSOI: 16 oCA

dSOI: 22 oCA

Diesel

DME



▌Brake Mean Effective Pressure - BMEP

Multiple injection

-4 -2 0 2 4Start of Main Injection [oCA]

460

480

500

520

540

560

580

600

620

640

BM

EP

[k

Pa]

dSOI: 0 oCA (Diesel)

dSOI: 0 oCA (DME)

dSOI: 10oCA (Diesel)

dSOI: 10oCA (DME)


dSOI: 16oCA (DME)


dSOI: 22oCA (DME)


▌Total Hydro Carbon - THC

Multiple injection


0

100

200

300

400

500

600

700

800

900

1000

1100

1200

1300

1400

1500

1600

1700

1800

TH

C [

pp

m]


dSOI: 0 oCA (DME)


dSOI: 10oCA (DME)


dSOI: 16oCA (DME)


dSOI: 22oCA (DME)


▌Carbon Monoxide - CO

Multiple injection


0

100

200

300

400

500

600

700

800

900

1000

1100

1200

1300

1400

1500

1600

1700

1800

CO

[p

pm

]


dSOI: 0 oCA (DME)


dSOI: 10oCA (DME)


dSOI: 16oCA (DME)


dSOI: 22oCA (DME)


▌Nitrogen Oxides - NOx

Multiple injection


0

100

200

300

400

500

600

700

800

900

1000

1100

1200

1300

1400

1500

1600

1700

1800

NO

x [

pp

m]


dSOI: 0 oCA (DME)


dSOI: 10oCA (DME)


dSOI: 16oCA (DME)


dSOI: 22oCA (DME)


▌Carbon monoxides - CO2

Multiple injection


8

8.5

9

9.5

10

10.5

11

CO

2 [

%]


dSOI: 0 oCA (DME)


dSOI: 10oCA (DME)


dSOI: 16oCA (DME)


dSOI: 22oCA (DME)


▌Thermal efficiency - th

Multiple injection


25

26

27

28

29

30

31

32

33

34

35

36

37

38

39

40

th

[-]


dSOI: 0 oCA (DME)


dSOI: 10oCA (DME)


dSOI: 16oCA (DME)


dSOI: 22oCA (DME)


Diesel & DME single injection

▌Emissions: NOx, CO, THC


0

150

300

450

600

750

900

CO

& T

HC

[p

pm

]

1000

1200

1400

1600

1800

2000

NO

x [

pp

m]

NOx: Diesel

NOx: DME

CO : Diesel

CO : DME

THC: Diesel

THC: DME


700 800 900 1000 1100 1200 1300 1400 1500 1600 1700 1800

NOx [ppm]

460

480

500

520

540

560

BM

EP

[kP

a]

SOImain:-4oCA aTDC

SOImain:-2oCA aTDC

SOImain: 0oCA aTDC

SOImain: 2oCA aTDC

SOImain: 4oCA aTDC

▪ CASE② (SOIsingle&main:364oCA, 16oCA)

▪ CASE③ (SOIsingle&main:364oCA, 10oCA)

- Significant NOx reduction without smoke

▌BMEP / NOx


DME

Speed = 1200 rpm


Pin,air = 1 bar


Tin,air = 25 ± 2 ℃

Qin = 1.31 kJ/cycle

Single injection

dSOI: 22oCA

dSOI: 16oCA

dSOI: 10oCA


DME

quantity

Diesel

quantity

Input

calories

Single 46 mm3 31 mm3 1.31 KJ/Cycle

2-Stage

Pilot 5.7 mm3

(1/8)

4 mm3

(1/8) 0.16 KJ/Cycle

Main 40.3 mm3

(7/8)

27 mm3

(7/8) 1.15 KJ/Cycle

Injection Strategy


Single dSOI 0 oCA

Main -4, -2, 0, 2, 4 oCA aTDC

2-Stage dSOI 10, 16, 22 oCA

Main -4, -2, 0, 2, 4 oCA aTDC

▌Injection timing

1.31 KJ/Cycle

1.15 KJ/Cycle

0.16 KJ/Cycle

dSOI


Camera

Shutter

Injection

Strobe

Light

Trigger

1000ms

1ms

8~20μsDelay

High Pressure Chamber

Injector

Strobe Light

PulseGenerator

Common Rail Solenoid Injector

Peak & Hold Driver

InjectorDriver

Computer

Camera

Delayed time

[ms]

Timing Diagram for Synchronization


DME Diesel





The number of injection 1000 times

DME Diesel





Experimental Condition of Spray

▌Injection quantity

▌Spray Shape [ length, angle ]


▌파일럿분사 적용 SOI Main Injection dSOI SOI Pilot Injection

oCA aTDC oCA oCA aTDC CASE 1

- 4

0 (Single injection) - 4

10 -14

16 -20

22 -26

CASE 2

- 2

0 (Single injection) -2

10 -12

16 -18

22 -24 CASE 3

0


10 -10

16 -16

22 -22 CASE 4

2

0 (Single injection) 2

10 8

16 14

22 20 CASE 5

4


10 6

16 12

22 18

Fuel injection rate [mg/oCA]

dSOI 0oCA 10oCA 16oCA 22oCA

CASE 1

- 4

0 (Single injection) - 4

10 -14

16 -20

22 -26

CASE 2

- 2


10 -12

16 -18

22 -24 CASE 3

0


10 -10

16 -16

22 -22 CASE 4

2


10 8

16 14

22 20 CASE 5

4


10 6

16 12

22 18

dSOI oCA

SOI Main Injection oCA aTDC

SOI Pilot Injection oCA aTDC

분사젂략


파일럿분사(Pilot injection): 예혼합연소에 의한 PM 저감

▌다단분사(Multiple injection): 연료를 나누어서 분사하는 기술

젂분사(Pre injection): 주분사의 착화지연에 의한 NOx, 진동 및 소음저감

후분사(After injection): 주연소의 활성화로 PM 저감

포스트분사(Post injection): 배기시스템에 장착된 촉매의 활성화

<출처 : Waseda Univ.>

주분사(Main injection): 출력향상 및 소음저감

Multiple injection


APPENDIX


Radial-piston pump

(Bosch)

Diesel Injection System





Accumulator

Air pump

Accumulator

Relief valve

CommonrailCheck valve

Injector

Return

Regulator

Compressor

Air

PCV

driver

Encoder

Encoder

interfacing box

Engine controller

A

B

Injector driver

■ Red: High pressure pump

■ Blue: Low pressure pump

■ Dotting: Signal

DME

Low pressure pump

Air driven liquid pump

(Haskel)

Chamber

Accumulator

N2

D

M

E


DME

Speed = 1200 rpm Pinjection = 700 bar Pin,air = 1 bar Tin,water = 80 ± 1 ℃ Tin,air = 25 ± 2 ℃ Qin = 1.31 KJ/Cycle

700 800 900 1000 1100 1200 1300 1400 1500 1600 1700 1800

NOx [ppm]

460

480

500

520

540

560

BM

EP

[kP

a]

SOImain:-4oCA aTDC

SOImain:-2oCA aTDC

SOImain: 0oCA aTDC

SOImain: 2oCA aTDC

SOImain: 4oCA aTDC

dSOI: 22oCA

dSOI: 16oCA

dSOI: 10oCA

Single injection

▌NOx / BMEP



700 800 900 1000 1100 1200 1300 1400 1500 1600 1700 1800

NOx [ppm]

460

480

500

520

540

560

BM

EP

[kP

a]

SOImain:-4oCA aTDC

SOImain:-2oCA aTDC

SOImain: 0oCA aTDC

SOImain: 2oCA aTDC

SOImain: 4oCA aTDC

Single injection

dSOI: 22oCA


▌NOx / BMEP


DME



700 800 900 1000 1100 1200 1300 1400 1500 1600 1700 1800

NOx [ppm]

460

480

500

520

540

560

BM

EP

[kP

a]

SOImain:-4oCA aTDC

SOImain:-2oCA aTDC

SOImain: 0oCA aTDC

SOImain: 2oCA aTDC

SOImain: 4oCA aTDC

Single injection

dSOI: 22oCA


▌NOx / BMEP


DME



700 800 900 1000 1100 1200 1300 1400 1500 1600 1700 1800

NOx [ppm]

460

480

500

520

540

560

BM

EP

[kP

a]

SOImain:-4oCA aTDC

SOImain:-2oCA aTDC

SOImain: 0oCA aTDC

SOImain: 2oCA aTDC

SOImain: 4oCA aTDC

Single injection

dSOI: 22oCA


▌NOx / BMEP


DME



700 800 900 1000 1100 1200 1300 1400 1500 1600 1700 1800

NOx [ppm]

460

480

500

520

540

560

BM

EP

[kP

a]

SOImain:-4oCA aTDC

SOImain:-2oCA aTDC

SOImain: 0oCA aTDC

SOImain: 2oCA aTDC

SOImain: 4oCA aTDCSingle injection

dSOI: 22oCA

dSOI: 16oCA 10oCA

▌NOx / BMEP


DME



▌CO / THC

Single injection

dSOI: 22oCA 16oCA

10oCA


DME



▌CO / THC

Single injection

dSOI: 22oCA



DME



▌CO / THC

Single injection

dSOI: 22oCA

dSOI: 16oCA

dSOI: 10oCA


DME



▌CO / THC

Single injection dSOI: 22oCA

dSOI: 16oCA

dSOI: 10oCA


DME



▌CO / THC

Single injection dSOI: 22oCA

dSOI: 16oCA 10oCA


DME



Tin = 353.15 ± 2 K Pin = 0.1 MPa Pinjection = 700 bar Qin = 1.31 KJ/Cycle

DME

0 100 200 300 400 500 600

CO [ppm]

0

100

200

300

400

500

600

TH

C[p

pm

]▌CO / THC


DME


DME injection Lower CO and THC emissions than diesel injection

Diesel

DME


NOx-Smoke trade-off




high temperature

Applying Pilot–main injection strategy for NOx reduction : K. Okude, K. Mori, S. Shiino, K. Yamada and Y. Matsumoto, “Effects of Multiple Injections on Diesel Emissions and

Combustion Characteristics”, SAE 2007-01-4178




SAE 2006-01-3324







▪ Good mixture formation & No wall wetting because of Low boiling

point

▌Advantages


paper 2005-03-0176, 2005



01-1862, 2004


NOx-Smoke trade-off




high temperature

Applying Pilot–main injection strategy for NOx reduction : K. Okude, K. Mori, S. Shiino, K. Yamada and Y. Matsumoto, “Effects of Multiple Injections on Diesel Emissions and

Combustion Characteristics”, SAE 2007-01-4178




SAE 2006-01-3324







▪ Good mixture formation & No wall wetting because of Low boiling

point

▌Advantages


paper 2005-03-0176, 2005



01-1862, 2004

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