NGP2010 Diesel Engine Briefing

Sept. 18, 2007

Yo Usuba Senior Vice President

Nissan Motor Co., Ltd.

Agenda
1. Environmental Technology Activities 2. Potential of Diesel Engines 3. Clean Diesels 4. Future Diesel Emissions Regulations 5. Japans Efforts to Reduce Emissions 6. Future Clean Diesels
. Environmental Technology Activities
Nissan Green Program 2010
Evolution of Engine and Transmission Introduction and Expansion of Electric Vehicles EV

VVEL FCV

In-house HEV

Li-ion Battery

Clean Diesel
3L Car Integrated approach collaborating with other sectors

SKY PROJECT

Engine Technology Roadmap
Technical challenges and long-term targets
Gasoline engine : CO2 emission reduction (-30%) Diesel engine : Exhaust emissions reduction (-90%)

almost ZEV

Exhaust Emissions
Evolution of Gasoline Engine
Theoretical Target Technology Breakthrough

BIN5 Euro6 Euro5 BIN10 0

Evolution of Diesel Engine

CO2 Reduction %

2. Potential of Diesel Engines
Comparison: Gasoline Engine and Diesel Engine
Although they are both internal combustion engines, they differ in output control and ignition method

Gasoline Engine

Injector Spark Plug Output is adjusted by air-fuel mixture amount controlled through the throttle valve Injector

Diesel Engine

ThrottleValveless

Spark ignition

Lean-burn condition
Fuel is injected right before entering the combustion c hamber
Fuel is directly injected into the combustion cham ber
High compression ratio Compression ignition
Stoichiometoric mixture ratio
Output is controlled by amount of fuel injection Output control Position of fuel injection Ignition method Compression ratio Air and fuel ratio
Mixture flow through throttle valve Intake port Spark ignition

Fuel injection amount

(throttle valveless)
Combustion chamber Compression ignition

Stoichiometric

Conventional diesel engines had high fuel efficiency and large torques, however emissions and vibration needed improvement Gasoline Engine
Intake port Spark ignition Position of fuel injection Injection method Compression ratio Air and fuel ratio Output control
Stoichiometric Mixture flow through throttle valve
Lean Fuel injection amount (throttle valveless)
Fuel injection into the combustion chamber
As fuel is directly injected into the combustion chamber, there is limited time for airfuel to evenly mix
Lean-burn condition High combustion pressure
Three-way catalyst is not available in lean-burn condition

Less pumping-loss

Combustion energy is efficiently converted into kinetic energy
NOx is generated NOx is generated
PM*(Soot) is generated PM*(Soot) is generated

*PM: Particulate Matter

High fuel efficiency High fuel efficiency Large vibration & noise Large vibration & noise Large torque Large torque

3. Clean Diesels

Clean Diesel: M9R
The M9R engine developed as part of the Renault-Nissan Alliance, achieves high efficiency, clean exhaust emissions, high power and low-noise.
The M9R cuts the 2 main complaints of the conventional diesel engines; noise and vibration. It also reduces regulated substances, meeting the Euro4 standard, while achieving top-level max power for a two-liter diesel engine.
Europe Diesel 2L passenger vehicle (FF) Max power Trend

Max Power (kw)

120 Average 100

60 '95 '00 '05 '10

[ CY ]
The M9R achieves top-level torque for a two-liter diesel engine as well, providing max torque of 360Nm from 1750rpm engine speeds.
Europe Diesel 2L passenger vehicle (FF) Torque Trend

300 Average

Torque Nm

100 '95 '00

Comparison:
Conventional Engine & Latest (M9R) Clean Engine
The level of technology applied in Nissan's M9R clean diesel engine is comparable to that in the CD20T, used in the first Serena in the 1990s.
Conventional Engine (CD20T) Latest Engine (M9R)
Restrains the generation of NOx and soot (PM)
Fuel-supply system: A common-rail system replaces the regular mechanical fuel pump
Fuel is under high pressure to ensure it injects as a fine mist and mixes more evenly with the air The system precisely controls fuel for optimal injection timing
Common rail Mechanical fuel pump

Fuel atomization

Injection nozzle High pressure fuel pump Injector
Conventional Engine (CD20T)
A mechanical pump injects fuel directly into each cylinder. Fuel pressure: 200 - 300bar

Latest Engine (M9R)

Fuel pressure is kept even, optimizing injection to each cylinder by electronic control. Fuel pressure: 1,600bar

What is 1600bar?

1600bar is equivalent to water pressure at the ocean depth of 16000m, which is larger than the water pressure at the deepest ocean trench Marian Trench.
Depth: 11000 Water pressure 1100bar
(1100 barometric pressure) Marian Trench
1600bar Equivalent to 16000m depth
Restrains the generation of soot (PM)
Air-intake port: The double swirl port guides air into the combustion chamber in high-speed swirls

Air and fuel mix evenly

Intake air swirls at high speed

Double swirl port

Prevents most emissions of soot (PM) The DPF disposes up to 99% of soot (PM)
Trapping and disposing of PM No Aftertreatment Device
Conventional Engine (CD20T)
It absorbs and deposits particulates generated by combustion. It oxidizes particulates by keeping the temperature of the DPF body at 600 degrees C. The DPF is self-cleaning and the cycle continues.

* DPF: Diesel Particulate Filter
Restrains the generation of NOx Added to reduce combustion temperature, the EGR cooler prevents the generation of NOx. EGR Valve
Further lowering combustion temperature

EGR System

EGR Cooler
Blowing inert exhaust gas into the combustion chamber lowers combustion temperature.
To lower combustion temperature, the EGR cooler cools the exhaust gas guided into the combustion chamber.
Noise restraint Highly responsive piezoelectric-controlled injectors allow multiple fuel streams of high accuracy. Dispersed combustion pressure under optimum control reduces combustion noise.

Piezoelectric element

Each injection is divided into several times streams
A mechanical fuel pump injects only one stream.
Common rail system (1600 bars) Piezoelectric-controlled injectors
Comparison: Conventional Engine & Latest (M9R) Clean Engine
Noise and vibration restraint Vibration is reduced by balance the moving parts of the engine
Reducing elements causing unbalance

Without Balancer

Balancer Shaft Conventional Engine (CD20T) Latest Engine (M9R)

Higher torque

A variable plate inside the turbocharger, controlled according to the speed of the exhaust stream, helps the turbo make big torque in the low-rpm range.

Variable nozzle

A variable nozzle increases turbocharger operating range

Turbocharger

Variable nozzle turbocharger

Clean Diesel (M9R)

The M9R cuts the 2 main complaints of the conventional diesel engines, noise and vibration. It also reduces regulated substances, meeting the Euro4 standard, while achieving top-level output for a two-liter diesel engine. Technology Items Common rail system (1600 bars) Piezoelectric-controlled injectors Double swirl port DPF* EGR (with EGR cooler) Variable nozzle turbo Balance shaft
*DPF: Diesel Particulate Filter
4. Future Diesel Emissions Regulations

Trend of Exhaust Emissions Regulations
Restrictions on diesel emissions are tightest in the U.S, but target Restrictions on diesel emissions are tightest in the U.S, but target figures alone cannot illustrate how tight the restrictions are figures alone cannot illustrate how tight the restrictions are because testing modes differ from region to region because testing modes differ from region to region

Europe

Euro5 Japan 2005 regulations

EURO5 technology

NOx (g/km)
New regulations (prediction)

(Euro6)

0.05 0.01
US Tier2Bin5 (Federal) US SULEV (California)
Differences in Driving Patterns (JPN, U.S, Europe)
Acceleration is high on the list in Japan and U.S, while high-speed driving is a more common need in Europe. Accel(G) Accel(G)
Usage Area 90percentile 60percentile

Accel(G)

Vehicle speed

(km/h)

Differences in Exhaust-Testing Mode (JPN, U.S, Europe)
Testing modes and restrictions differ depending on region

(km/h ) 100

JC08 JPN Mode

Transi ent mo de

from 2008 year

Time (se c)

U.S. LA4

(mile/h ) 0

100km/h 50km/h

2500 Time (se c)

(km/h ) 140

Europe EUDC

ECE + Mode
5. Japans Efforts to Reduce Emissions
Clean Diesel (M9R) JPN model (Fall 2008)
Japans New Long-term Regulations are more stringent, requiring PM reduction by 45% and NOx reduction by 40% against Europes Euro4 Regulations. Therefore, Nissan has added technology to enhance NOx removal performance.
- NOx-trap catalyst (LNT*) added - As there are more transient driving patterns compared to Europe, advanced engine combustion control technology has been added 0.25

0.2 Euro3

(km/h) 100

JPNJC08 Mode

(from 2008)

Time ( sec)

Japans H17 New Longterm Regulations

(km/h) 140 100

Europe ECE +EUDC Mode
Japans H17 Post New Long-term Regulations 0.01
*LNT: Lean NOx Trap catalyst

PM (g/km)

6. Future Clean Diesels
Development of Future Clean Diesels: SULEV*
Developing technology aiming at the ultimate goal of cleaning exhaust emissions to meet SULEV requirements

0.25 NOx (g/km)

0.1 Euro4 Japans H17 Post New Long-term Regulations

Tier2Bin5 SULEV*

NOx 70% reduction

0.01 0.02 PM (g/km)

*The State of California Emission Standards
Presently, HC is reduced by 90% and NOx is reduced by 70% against Tier2Bin5 standards.

(g/km) (g/km)

0.05 0.04
0.06 0.05 0.04 0.03 0.02 0.Bin5 SULEV*

0.03 0.02 0.Bin5

SULEV*
3 technologies that support SULEV*
Improvement in combustion technology
MK combustion curbs regulated substances at its origin-phase
Newly developed HC-NOx trap catalyst
Improves NOx conversion efficiency using trapped HC which is regulated substances CO H O CO

O2 N2 N

N2 CO H2 C O NO HC HC CO CO

C O2 CO

NOx reduction layer NOx-trap layer HC-trap layer

HC-NOx trap catalyst

Advanced engine control realizes a highly efficient catalyst as well as combustion improvement

HC-NOx Trap Catalyst

While conventional NOx-trap catalysts reduced only NOx, the new catalyst has an additional HC-trap layer to efficiently use HC, a regulated substance, for generating a chemical reaction to reduce NOx. This realizes highly efficient removal of both HC and NOx.

Conditions for lean burn

(diagram) NO O2 N2 NO reduction layer NO NO NO trap layer HC HC trap layer H 2 CO NO H 2 CO NO HC O2

Conditions for rich burn

(diagram) N2 H 2O CO2 H 2O CO2
1. NO is oxidized and NOx is a bsorbed by the trap layer
2. The system uses a small controlled amount of O2 with HC to generate H 2 and Co, which together perform a highly efficient NOx chemical reaction.
Development of Future Clean Diesels
Aiming at the technology goal of cleaning engine emissions to the atmospheric level, Nissan will further technology development for CO2 reduction

Theoretical Target