March 17, 2006 Ronald Reagan Building And International Trade Center Washington, DC, US
Conference on the Development and Promotion of
Environmentally Friendly Heavy Duty Vehicles such as DME Trucks
Development of a Heavy-Duty DME Truck in EFV21 Project
Yoshio Sato 1 , Akira Nakamura 2
1
National Traffic Safety and Environment Laboratory, Japan
2
Nissan Diesel Motor Co., Ltd, Japan
Contents
¾ EFV21 project
– Background, Targets
¾ Technical challenges
– Fuel system
– Emissions control system
• Large volume Exhaust Gas Recirculation (EGR)
• NOx storage reduction (NSR) catalyst
– Test results
¾ Development of H/D DME truck
¾ Conclusions
Environmental impact of diesel trucks
Passenger cars
Mini sized trucks Light duty trucks
Standard trucks
Small sized trucks Passenger cars Buses
Special vehicles
NOx
FY2001
Gasoline 20 %
Diesel 80 %
Mini sized passenger cars
Standard Diesel trucks
Diesel small sized trucks Diesel
passenger cars
Diesel buses
PM
FY2001 Diesel
100％
Diesel special vehicles
Number ratio of diesel trucks ; 3.3 %
Database: http://www.env.go.jp/en/
Task of EFV21 project
- from the Action Plan of Clean Vehicles (METI, MLIT, MOE, Jul. 2001)
- from the Working Group Report (MLIT, Dec. 2001 )
“The Next-Generation Low Emission Heavy-duty vehicles”
- Drastic reduction of exhaust emission maintaining good fuel efficiency
- Improvement of practical use
Output, Fuel economy, Cruising distance
Environmentally Friendly Vehicles 21
“EFV21” Project
Basic data of EFV21 project
¾ Time period:
– 3 years, from April 2002 through March 2005
¾ Subjects:
– Completion of prototype vehicles by March 2005, and evaluation of the vehicles' performance
¾ Prototype vehicles and engine:
– DME fueled truck, Ultra-Clean CNG fueled truck, Series H/B diesel bus, Parallel H/B diesel truck, Ultra-Clean diesel engine
¾ Development budget:
– Support from Ministry of Land, Infrastructure and Transport (MLIT)
– Total budget included all vehicles for 3 years;
Approximately 5 billion yen (approximately 42 million
dollars)
Development targets for DME truck
¾ Exhaust emissions (JE-05 mode, 2005):
NOx = 0.5g/kWh or less
PM ≒0.0g/kWh (nearly zero) CO = 2.22g/kWh or less
NMHC = 0.17g/kWh or less
¾ Fuel consumption:
Equivalent to base diesel engine
¾ Engine power:
Equivalent to base diesel engine
¾ Cruising distance and load capacity:
Equivalent to base diesel truck
Emissions target of EFV21 project
Emissions regulation for H/D diesel engine
0.00 0.05 0.10 0.15 0.20 0.25
0 1 2 3 4
NOx g/kWh
PM g/ k W h
2004 US
2007 US
2005 EURO4 2008
EURO5
2003/04 JAPAN
2005 JAPAN 2010
US
Strategic target, -2010
Target of EFV21 - Mar. 2005
2009 JAPAN
0.27 0.013
0.5 0.2
Specifications of DME engine
Base engine NISSAN DIESEL FE6T
Cylinder L6
Bore / Stroke 108 / 126 Displacement 6,925cc
Charge type Turbocharger with intercooler
Achieved max. output 199kW at 2700rpm 750Nm at 1100rpm Achieved max. torque
Compression ratio 17.5
Valve system OHV (2 valves per cylinder)
Swirl ratio 1.9
Fuel injection system Jerk type In-line injection
Fuel system for DME vehicles
Fuel temperature control unit
Purge line
Supply & return line Re-liquefaction line
High pressure pump Injector
Feed pump Filter
Fuel temperature control unit
DME tank Purge tank
Re-liquefaction pump
Aspirator Aspirator
Suction Suction
Inlet
Inlet OutletOutlet
NOx reduction by large volume EGR
Effect of EGR at 1620rpm
High-EGR system
60% speed (1620rpm)-6 -4 -2 0 2 4 6 8 10
Rate of change of BSFC [%]
-100 -80 -60 -40 -20 0
NOx reduction rate [%]
Turbocharger Air filter
EGR valve
DME engine
Inter-cooler
Exhaust manifold Intake manifold
EGR Gas
EGR Gas Throttle valve
20%Load 40%Load 60%Load 80%
Load
20%Load
40%Load
60%Load 80%Load
Air + EGR gas
High-pressure to
Low-pressure EGR
NOx storage reduction catalyst system
NSR catalyst
Exhaust gas temp. sensor NOx concentration sensor
Oxdation catalyst
Exhaust gas temp. sensor NOx concentration sensor
Engine out
NOx CO HC
Exhaust
Rich spike injector Reducing agent
（DME）
CO
2H
2O
N
2NOx behavior in emissions test
Exhaust emissions result
0 1 2 3
NOx NMHC CO
Exhaust emission [g/kWh]
0.00 0.01 0.02 0.03 0.04
PM
Exhaust emission [g/kWh]
0.001 2009 Regulation
Achievement data（Dec. 2004）
Target of project 2005 Regulation
0.11 0.12 0.21
Emissions profile
Emission regulation for H/D diesel engine
0.00 0.05 0.10 0.15 0.20 0.25
0 1 2 3 4
NOx g/kW h
PM g/ kWh
2004US2007 US
2005 EURO4 2008
EURO5
2003/04 JAPAN
2005 JAPAN 2010
US
Achievement data (Dec. 2004)
Target of EFV21 - Mar. 2005
2009 JAPAN
CO 2 emission characteristics
5 10 15 20 25
50g/kWh
CO
2range Of D.E.
DME Engine （EGR + NSR Cat.）
: NOx 0.35 g/kWh（JE-05）
: NOx 0.11 g/kWh（JE-05）
6.9L
CO
2range of D.E.
(Displacement：6.9L)
CO
2emission （g/kWh ） [ D-13 mode test ]
0
Engine displacement (L)
Output of DME engine
800
DIESEL (Target)
DME
700
Torque [Nm]
600
500
400
300
500 1000 1500 2000 2500 3000
Fuel consumption profile
NOx [g/kWh]
BSFC [g/kWh]
200 250 300
3 4 5 6
2 1
0
EGR
Transient mode (JE-05 mode)
EGR + NSR DIESEL
DME
Steady state mode (Diesel 13 mode)
Target
0.5 g/kWh
New long-termFuel and emissions system
Silencer ECU
Turbocharger
EGR valve
Fuel Injector
ENGINE
Feed pump
Injection pump
Supply unit
of reducing agent
DME tank
Oxidation catalyst
Oxidation catalyst
NOx storage reduction catalyst
Inter- cooler
DME truck specifications
DME engine
Feed pump
DME tank
Reducing agent Control unit
Fuel temperature control unit
Fuel pressure &
Purge control unit NISSAN DIESEL, PW25A
Heavy duty truck
Overall Length [m] 12
Overall Width [m] 2.5
Overall Height [m] 3.4
10
342 (171 + 171) 627 *
*Calculated value from the JE-05 mode test result DME tank capacity [liters]
Driving range [km]
Base truck Type Dimension
Maximum payload [tons]
Gross vehicle weight [tons] 20
Side-view of fuel system
Fuel temperature control unit
Fuel pressure control unit
DME tank
Feed pump
Vehicle acceleration performance
0 5 10 15 20 25
20 40 60 80 100 120
GVW 14.4 ton GVW
9.1 ton
GVW 19.8 ton
DME
Diesel
(GVW: 8-25ton)
Time 0-200 m [ sec.]
Power weight ratio GVW [kg] / max.power [kW]
Conclusions
¾ Heavy-duty dimethyl ether (DME) trucks developed and tested jointly by the National Traffic Safety and Environment Laboratory and Nissan Diesel Motor Co., have exceeded the upcoming 2010 US heavy-duty emissions regulations.
¾ Through the optimization of the combustion
system and the combination of emission
reduction technologies, the DME truck
achieves the same level of fuel consumption
(BSFC), output, cruising distance and payload
as conventional diesel vehicles, while
significantly reducing emissions.
Field test of DME truck/2006-2008
Step
2002 2005 2006 2008 2010 2015 2020
Engine and Truck Development Budget year
Widespread Use Practical
Use Truck
Field Test
DME Infrastructure
