effects of pilot injection strategies on spray
Post on 22-Jan-2022
8 Views
Preview:
TRANSCRIPT
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
Smart Powertrain Lab.
▌INTRODUCTION
Contents
▌OBJECTIVES
▌EXPERIMENTAL SETUP
▪ Spray Experimental System
▪ Engine Experiment System
▌CONCLUSION
▌RESULTS
▪ Spray Experiment
▪ Engine Experiment
Smart Powertrain Lab.
▌INTRODUCTION
Contents
▌OBJECTIVES
▌EXPERIMENTAL SETUP
▪ Spray Experimental System
▪ Engine Experiment System
▌CONCLUSION
▌RESULTS
▪ Spray Experiment
▪ Engine Experiment
Smart Powertrain Lab.
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
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
Smart Powertrain Lab.
- 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
DME Engine Characteristics
Smart Powertrain Lab.
- 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
DME Engine Characteristics
Smart Powertrain Lab.
▌INTRODUCTION
Contents
▌OBJECTIVES
▌EXPERIMENTAL SETUP
▪ Spray Experimental System
▪ Engine Experiment System
▌CONCLUSION
▌RESULTS
▪ Spray Experiment
▪ Engine Experiment
Smart Powertrain Lab.
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
Smart Powertrain Lab.
▌INTRODUCTION
Contents
▌OBJECTIVES
▌EXPERIMENTAL SETUP
▪ Spray Experimental System
▪ Engine Experiment System
▌CONCLUSION
▌RESULTS
▪ Spray Experiment
▪ Engine Experiment
Smart Powertrain Lab.
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
Smart Powertrain Lab.
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
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)
N2
DME
Pressurization
≈ 15 bar Fuel
outlet
(Liquid)
N2
N2
Fuel
inlet
Fuel
outlet
Vane
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)
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
Smart Powertrain Lab.
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
Smart Powertrain Lab.
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
Smart Powertrain Lab.
▌INTRODUCTION
Contents
▌OBJECTIVES
▌EXPERIMENTAL SETUP
▪ Spray Experimental System
▪ Engine Experiment System
▌CONCLUSION
▌RESULTS
▪ Spray Experiment
▪ Engine Experiment
Smart Powertrain Lab.
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
Smart Powertrain Lab.
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
Fuel Injection System
for DME injection
DME Testing
Exhaust -Gas
Analyzers
(Horiba
MEXA-7100
DEGR)
CO
HC
NOx
Common-rail
Fuel Injection System
for Diesel injection
Diesel Testing
Schematic of Engine Facility
Smart Powertrain Lab.
▌INTRODUCTION
Contents
▌OBJECTIVES
▌EXPERIMENTAL SETUP
▪ Spray Experimental System
▪ Engine Experiment System
▌CONCLUSION
▌RESULTS
▪ Spray Experiment
▪ Engine Experiment
Smart Powertrain Lab.
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
Smart Powertrain Lab.
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
Smart Powertrain Lab.
▌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 ℃
Smart Powertrain Lab.
Spray Shape
▌DME Spray Shape [ΦInjector = 0.300 mm]
Fuel = DME
ΦInjector = 0.300 mm
Pinject = 700 bar
Po = 55 bar (by N2)
To = 25 ± 1 ℃
Smart Powertrain Lab.
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
ΦInjector = 0.166 mm
Pinject = 700 bar
Po = 55 bar (by N2)
To = 25 ± 1 ℃
▌DME Spray Shape [ΦInjector = 0.300 mm] Fuel = DME
ΦInjector = 0.300 mm
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
Smart Powertrain Lab.
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
Smart Powertrain Lab.
▌INTRODUCTION
Contents
▌OBJECTIVES
▌EXPERIMENTAL SETUP
▪ Spray Experimental System
▪ Engine Experiment System
▌CONCLUSION
▌RESULTS
▪ Spray Experiment
▪ Engine Experiment
Smart Powertrain Lab.
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
Smart Powertrain Lab.
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 Quantity
Smart Powertrain Lab.
▌ 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
Smart Powertrain Lab.
▌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
Smart Powertrain Lab.
Speed = 1200 rpm
Pinjection = 700 bar
Pin,air = 1 bar
Tin,water = 80 ± 1 ℃
Tin,air = 25 ± 2 ℃
Qin = 1.31 kJ/cycle
▌BMEP / NOx
Emission Characteristic
Diesel
DME
Single injection
dSOI: 22oCA
dSOI: 16oCA dSOI: 10oCA
Smart Powertrain Lab.
Speed = 1200 rpm
Pinjection = 700 bar
Pin,air = 1 bar
Tin,water = 80 ± 1 ℃
Tin,air = 25 ± 2 ℃
Qin = 1.31 kJ/cycle
▌Smoke / NOx
Emission Characteristic
Diesel
DME
Smart Powertrain Lab.
▌CO+THC / NOx
Emission Characteristic
Speed = 1200 rpm
Pinjection = 700 bar
Pin,air = 1 bar
Tin,water = 80 ± 1 ℃
Tin,air = 25 ± 2 ℃
Qin = 1.31 kJ/cycle
Diesel
DME
Smart Powertrain Lab.
▌INTRODUCTION
Contents
▌OBJECTIVES
▌EXPERIMENTAL SETUP
▪ Spray Experiment
▪ Engine Experiment
▌CONCLUSION
▌RESULTS
▪ Spray Experiment
▪ Engine Experiment
Smart Powertrain Lab.
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
Smart Powertrain Lab.
Thank you for listening.
Smart Powertrain Lab.
APPENDIX
Smart Powertrain Lab.
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: -2 oCA aTDC (Diesel)
SOIMain: -2 oCA aTDC (DME)
SOIMain: 0 oCA aTDC (Diesel)
SOIMain: 0 oCA aTDC (DME)
SOIMain: 2 oCA aTDC (Diesel)
SOIMain: 2 oCA aTDC (DME)
SOIMain: 4 oCA aTDC (Diesel)
SOIMain: 4 oCA aTDC (DME)
0 Single injection
Smart Powertrain Lab.
NOx
4 10 16 22Dwell time between pilot & main injections [oCA]
700
800
900
1000
1100
1200
1300
1400
1500
1600
1700
1800
NO
x[p
pm
]
SOIMain: -4 oCA aTDC (Diesel)
SOIMain: -4 oCA aTDC (DME)
SOIMain: -2 oCA aTDC (Diesel)
SOIMain: -2 oCA aTDC (DME)
SOIMain: 0 oCA aTDC (Diesel)
SOIMain: 0 oCA aTDC (DME)
SOIMain: 2 oCA aTDC (Diesel)
SOIMain: 2 oCA aTDC (DME)
SOIMain: 4 oCA aTDC (Diesel)
SOIMain: 4 oCA aTDC (DME)
0
▌Diesel injection VS Pilot-main injection
Single injection
Smart Powertrain Lab.
CO
4 10 16 22Dwell time between pilot & main injections [oCA]
0
50
100
150
200
250
300
350
400
CO
[pp
m]
SOIMain: -4 oCA aTDC (Diesel)
SOIMain: -4 oCA aTDC (DME)
SOIMain: -2 oCA aTDC (Diesel)
SOIMain: -2 oCA aTDC (DME)
SOIMain: 0 oCA aTDC (Diesel)
SOIMain: 0 oCA aTDC (DME)
SOIMain: 2 oCA aTDC (Diesel)
SOIMain: 2 oCA aTDC (DME)
SOIMain: 4 oCA aTDC (Diesel)
SOIMain: 4 oCA aTDC (DME)
0
▌Diesel injection VS Pilot-main injection
Single injection
Smart Powertrain Lab.
THC
4 10 16 22Dwell time between pilot & main injections [oCA]
0
50
100
150
200
250
300
350
TH
C[p
pm
]
SOIMain: -4 oCA aTDC (Diesel)
SOIMain: -4 oCA aTDC (DME)
SOIMain: -2 oCA aTDC (Diesel)
SOIMain: -2 oCA aTDC (DME)
SOIMain: 0 oCA aTDC (Diesel)
SOIMain: 0 oCA aTDC (DME)
SOIMain: 2 oCA aTDC (Diesel)
SOIMain: 2 oCA aTDC (DME)
SOIMain: 4 oCA aTDC (Diesel)
SOIMain: 4 oCA aTDC (DME)
0
▌Diesel injection VS Pilot-main injection
Single injection
Smart Powertrain Lab.
Smoke
0
▌Diesel injection VS Pilot-main injection
Single injection
Smart Powertrain Lab.
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
Smart Powertrain Lab.
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/o
CA
]
-2 oCA aTDC
dSOI: 0 oCA
dSOI: 10 oCA
dSOI: 16 oCA
dSOI: 22 oCA
Diesel
DME
Heat-release rates (358oCA)
▌A comparison of heat-release rates in diesel & DME
Smart Powertrain Lab.
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/o
CA
]
0 oCA aTDC
dSOI: 0 oCA
dSOI: 10 oCA
dSOI: 16 oCA
dSOI: 22 oCA
Diesel
DME
Heat-release rates (360oCA)
▌A comparison of heat-release rates in diesel & DME
Smart Powertrain Lab.
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/o
CA
]
2 oCA aTDC
dSOI: 0 oCA
dSOI: 10 oCA
dSOI: 16 oCA
dSOI: 22 oCA
Diesel
DME
Heat-release rates (362oCA)
▌A comparison of heat-release rates in diesel & DME
Smart Powertrain Lab.
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
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]
Diesel
Heat-release rates (364oCA)
▌A comparison of heat-release rates in diesel & DME
DME
Smart Powertrain Lab.
340 345 350 355 360 365 370 375 380 385 390Crank Angle [oCA aTDC]
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)
Smart Powertrain Lab.
340 345 350 355 360 365 370 375 380 385 390Crank Angle [oCA aTDC]
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
Pressure traces (358oCA)
Smart Powertrain Lab.
340 345 350 355 360 365 370 375 380 385 390Crank Angle [oCA aTDC]
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
Pressure traces (360oCA)
Smart Powertrain Lab.
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
340 345 350 355 360 365 370 375 380 385 390Crank Angle [oCA aTDC]
20
30
40
50
60
70
80
90
Cylin
der
Pre
ssu
re[b
ar]
Diesel
DME
Pressure traces (362oCA)
Smart Powertrain Lab.
340 345 350 355 360 365 370 375 380 385 390Crank Angle [oCA aTDC]
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 (364oCA)
Smart Powertrain Lab.
▌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 (Diesel)
dSOI: 16oCA (DME)
dSOI: 22oCA (Diesel)
dSOI: 22oCA (DME)
Smart Powertrain Lab.
▌Total Hydro Carbon - THC
Multiple injection
-4 -2 0 2 4Start of Main Injection [oCA]
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 (Diesel)
dSOI: 0 oCA (DME)
dSOI: 10oCA (Diesel)
dSOI: 10oCA (DME)
dSOI: 16oCA (Diesel)
dSOI: 16oCA (DME)
dSOI: 22oCA (Diesel)
dSOI: 22oCA (DME)
Smart Powertrain Lab.
▌Carbon Monoxide - CO
Multiple injection
-4 -2 0 2 4Start of Main Injection [oCA]
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 (Diesel)
dSOI: 0 oCA (DME)
dSOI: 10oCA (Diesel)
dSOI: 10oCA (DME)
dSOI: 16oCA (Diesel)
dSOI: 16oCA (DME)
dSOI: 22oCA (Diesel)
dSOI: 22oCA (DME)
Smart Powertrain Lab.
▌Nitrogen Oxides - NOx
Multiple injection
-4 -2 0 2 4Start of Main Injection [oCA]
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 (Diesel)
dSOI: 0 oCA (DME)
dSOI: 10oCA (Diesel)
dSOI: 10oCA (DME)
dSOI: 16oCA (Diesel)
dSOI: 16oCA (DME)
dSOI: 22oCA (Diesel)
dSOI: 22oCA (DME)
Smart Powertrain Lab.
▌Carbon monoxides - CO2
Multiple injection
-4 -2 0 2 4Start of Main Injection [oCA]
8
8.5
9
9.5
10
10.5
11
CO
2 [
%]
dSOI: 0 oCA (Diesel)
dSOI: 0 oCA (DME)
dSOI: 10oCA (Diesel)
dSOI: 10oCA (DME)
dSOI: 16oCA (Diesel)
dSOI: 16oCA (DME)
dSOI: 22oCA (Diesel)
dSOI: 22oCA (DME)
Smart Powertrain Lab.
▌Thermal efficiency - th
Multiple injection
-4 -2 0 2 4Start of Main Injection [oCA]
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
th
[-]
dSOI: 0 oCA (Diesel)
dSOI: 0 oCA (DME)
dSOI: 10oCA (Diesel)
dSOI: 10oCA (DME)
dSOI: 16oCA (Diesel)
dSOI: 16oCA (DME)
dSOI: 22oCA (Diesel)
dSOI: 22oCA (DME)
Smart Powertrain Lab.
Diesel & DME single injection
▌Emissions: NOx, CO, THC
-4 -2 0 2 4Start of Main Injection [oCA]
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
Smart Powertrain Lab.
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
Emission Characteristic
DME
Speed = 1200 rpm
Pinjection = 700 bar
Pin,air = 1 bar
Tin,water = 80 ± 1 ℃
Tin,air = 25 ± 2 ℃
Qin = 1.31 kJ/cycle
Single injection
dSOI: 22oCA
dSOI: 16oCA
dSOI: 10oCA
Smart Powertrain Lab.
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 Quantity
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
Smart Powertrain Lab.
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
Smart Powertrain Lab.
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
DME Diesel
Injector diameter Φ = 0.300 mm Φ = 0.166 mm
Injection pressure 700 bar
Ambient pressure 55 bar
Injection duration 1ms
Experimental Condition of Spray
▌Injection quantity
▌Spray Shape [ length, angle ]
Smart Powertrain Lab.
▌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
0 (Single injection) -0
10 -10
16 -16
22 -22 CASE 4
2
0 (Single injection) 2
10 8
16 14
22 20 CASE 5
4
0 (Single injection) 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
0 (Single injection) -2
10 -12
16 -18
22 -24 CASE 3
0
0 (Single injection) -0
10 -10
16 -16
22 -22 CASE 4
2
0 (Single injection) 2
10 8
16 14
22 20 CASE 5
4
0 (Single injection) 4
10 6
16 12
22 18
dSOI oCA
SOI Main Injection oCA aTDC
SOI Pilot Injection oCA aTDC
분사젂략
Smart Powertrain Lab.
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
Smart Powertrain Lab.
APPENDIX
Smart Powertrain Lab.
Radial-piston pump
(Bosch)
Diesel Injection System
Smart Powertrain Lab.
DME Injection System
Smart Powertrain Lab.
DME 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
Smart Powertrain Lab.
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
Emission Characteristic
Smart Powertrain Lab.
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
dSOI: 16oCA dSOI: 10oCA
▌NOx / BMEP
Emission Characteristic
DME
Speed = 1200 rpm Pinjection = 700 bar Pin,air = 1 bar Tin,water = 80 ± 1 ℃ Tin,air = 25 ± 2 ℃ Qin = 1.31 KJ/Cycle
Smart Powertrain Lab.
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
dSOI: 16oCA dSOI: 10oCA
▌NOx / BMEP
Emission Characteristic
DME
Speed = 1200 rpm Pinjection = 700 bar Pin,air = 1 bar Tin,water = 80 ± 1 ℃ Tin,air = 25 ± 2 ℃ Qin = 1.31 KJ/Cycle
Smart Powertrain Lab.
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
dSOI: 16oCA dSOI: 10oCA
▌NOx / BMEP
Emission Characteristic
DME
Speed = 1200 rpm Pinjection = 700 bar Pin,air = 1 bar Tin,water = 80 ± 1 ℃ Tin,air = 25 ± 2 ℃ Qin = 1.31 KJ/Cycle
Smart Powertrain Lab.
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
Emission Characteristic
DME
Speed = 1200 rpm Pinjection = 700 bar Pin,air = 1 bar Tin,water = 80 ± 1 ℃ Tin,air = 25 ± 2 ℃ Qin = 1.31 KJ/Cycle
Smart Powertrain Lab.
▌CO / THC
Single injection
dSOI: 22oCA 16oCA
10oCA
Emission Characteristic
DME
Speed = 1200 rpm Pinjection = 700 bar Pin,air = 1 bar Tin,water = 80 ± 1 ℃ Tin,air = 25 ± 2 ℃ Qin = 1.31 KJ/Cycle
Smart Powertrain Lab.
▌CO / THC
Single injection
dSOI: 22oCA
dSOI: 16oCA dSOI: 10oCA
Emission Characteristic
DME
Speed = 1200 rpm Pinjection = 700 bar Pin,air = 1 bar Tin,water = 80 ± 1 ℃ Tin,air = 25 ± 2 ℃ Qin = 1.31 KJ/Cycle
Smart Powertrain Lab.
▌CO / THC
Single injection
dSOI: 22oCA
dSOI: 16oCA
dSOI: 10oCA
Emission Characteristic
DME
Speed = 1200 rpm Pinjection = 700 bar Pin,air = 1 bar Tin,water = 80 ± 1 ℃ Tin,air = 25 ± 2 ℃ Qin = 1.31 KJ/Cycle
Smart Powertrain Lab.
▌CO / THC
Single injection dSOI: 22oCA
dSOI: 16oCA
dSOI: 10oCA
Emission Characteristic
DME
Speed = 1200 rpm Pinjection = 700 bar Pin,air = 1 bar Tin,water = 80 ± 1 ℃ Tin,air = 25 ± 2 ℃ Qin = 1.31 KJ/Cycle
Smart Powertrain Lab.
▌CO / THC
Single injection dSOI: 22oCA
dSOI: 16oCA 10oCA
Emission Characteristic
DME
Speed = 1200 rpm Pinjection = 700 bar Pin,air = 1 bar Tin,water = 80 ± 1 ℃ Tin,air = 25 ± 2 ℃ Qin = 1.31 KJ/Cycle
Smart Powertrain Lab.
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
Emission Characteristic
DME
Speed = 1200 rpm Pinjection = 700 bar Pin,air = 1 bar Tin,water = 80 ± 1 ℃ Tin,air = 25 ± 2 ℃ Qin = 1.31 KJ/Cycle
DME injection Lower CO and THC emissions than diesel injection
Diesel
DME
Smart Powertrain Lab.
NOx-Smoke trade-off
▌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
- 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
▌Smoke formation in CI engine
Smart Powertrain Lab.
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 because of Low boiling
point
▌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
Smart Powertrain Lab.
NOx-Smoke trade-off
▌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
- 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
▌Smoke formation in CI engine
Smart Powertrain Lab.
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 because of Low boiling
point
▌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
top related