Technical Challenges and OpportunitiesLight-Duty Diesel Engines in North America

August 24, 2005Chicago

Technical Challenges and OpportunitiesLight-Duty Diesel Engines in North America

August 24, 2005Chicago

John PinsonGroup Manager Diesel R&DGeneral Motors Corporation

2

Spe

cific

Pow

er (k

W/l)

Future HSDIDiesel Engines

Spe

cific

Pow

er (h

p/l)

Turbo ChargedSI Engines

4V-SI Engines

80

60

20

0

40

20

100

60

0

40

80

2V-SIEngines

1930 1940 1950 1960 1970 1980 1990 2000 2010

Diesel EnginesNaturally AspiratedTurbocharged (TC)TC-Intercooled

Model YearSource: FEV Data

Benchmark Power Density Trends Benchmark Power Density Trends

3

Evolution of Specific TorqueEvolution of Specific Torque

Power Density (kW/l)50

2005+2005+GasolineGasoline

Turbo SIDITurbo SIDI

2005+2005+DieselDiesel

22--stage Turbostage Turbo

20052005performanceperformance

gasoline turbogasoline turbo

20052005Diesel turboDiesel turboAdv. Comb.Adv. Comb.

20052005

19901990Gasoline turboGasoline turbo

19901990Diesel Diesel TurboTurbo

19901990Gasoline

Naturally Aspirated

Torq

ue D

ensi

ty (

Nm

/l)

100

100

200 ??Next Gen.

Diesel?

4

Emission EvolutionEmission EvolutionEuro 3 (2000)

Euro 4 (2005)

Euro 5Prop

Tier 2, Bin 10 (2007-2010)

T2 Bin 5 10-14k HD Chassis

0

0.01

0.02

0.03

0.04

0.05

0.06

0.07

0.08

0.09

0 0.1 0.2 0.3 0.4 0.5 0.6 0.7 0.8 0.9 1NOx (g/mi)

Part

icul

ate

Mat

ter (

g/m

i)

T2 Bin 8 / 8.5-10k HD Chassis

Low Temperature Combustion (near-HCCI)Air/EGR System InnovationCombustion Feedback Control

Innovations in Lean NOx ATActive Dispersion Management

Injection System, Cooled EGR, Reduced Compression Ratio

5

NOx – Load RequirementsNOx – Load Requirements

2 4 6 8 10 120

1

2

3

4

5

6Euro 5

Tier 2Bin 8

Tier 2Bin 5

Tier 2Bin 2

Emis

sion

Inde

x N

Ox

(g/k

g fu

el)

Engine BMEP (Bar)

Engine-Out Asymptote?

6

Clean Combustion with DieselClean Combustion with Diesel

NOx

Soot

Equ

ival

ence

Rat

io

10987654321

Temperature (K)1000 1400 1800 2200 2600 3000

Com

bust

ion

Effic

ienc

y H

C/C

O Is

sues

Conventional CombustionFuel rich combustion leads to NOx and PM formation.

Conventional

Near-HCCI CombustionTight control on charge temperature and mixture formation is required

7

Near-HCCI Potential for DieselNear-HCCI Potential for Diesel

0

0.2

0.4

0.6

0.8

1

1.2

1.4

1.6

0 1 2 3 4 5 6 7Engine Out NOx (g/kg)

Bos

ch S

mok

e N

umbe

r

ConventionalCombustion(Euro 4/5 Cal)

8

Near-HCCICombustion

Simulated Vehicle Cruise Condition

8

Towards Wide Range Charge ControlTowards Wide Range Charge Control

System Complexity

Cha

rge

Tem

pera

ture

Conventional EGR Cooler

+ Optimized EGR cooler+ Bypass for light-load and cold operation

+ Separate water circuit

+ Clean EGR (low pressure)

Temperature and composition

+ VVA

VGT

2-Stage

EmergingConcepts

VGC

Boost System EvolutionAirAir--System FoulingSystem Fouling

Fouled EGR Cooler Tube

9

The Next RevolutionThe Next RevolutionThe Next Revolution

Near-HCCI combustion Ultra-low NOx operationTransients + mode switching

Adaptive dispersion controlComponent wearEnvironmental factors

Enhanced OBD diagnostics

Lots of development to do!

Near-HCCI combustion Ultra-low NOx operationTransients + mode switching

Adaptive dispersion controlComponent wearEnvironmental factors

Enhanced OBD diagnostics

Lots of development to do!

ECU

Combustion Sensor

Regaining control with direct combustion-feedback

10

0.6

0.8

1.0

1.2

1.4

65 70 75 80 85 90 95Time (s)

Control OffControl On

Combustion FeedbackCombustion Feedback

TargetFueling

Over

Under

Production Variability

An example of injector dispersion control

11

Ligh

t Dut

y D

iese

l US0

6 C

atal

yst T

emps

Ligh

t Dut

y D

iese

l FTP

C

atal

yst T

empe

ratu

res

Balancing catalyst activity between the FTP & US06Lean-NOx Aftertreatment OptionsLean-NOx Aftertreatment Options

0

20

40

60

80

100

0 100 200 300 400 500 600

SCR-Urea 1

NO

xC

o nve

rsio

n E

ffici

e ncy

(%)

Catalyst Operating Temperature (degrees C)

LNT 2

SCR-HC 3

1 Aged 120 k mi, transition metal Zeolite 2 Aged 120 k mi, vehicle measurement3 Aged 120 k mi, transition metal Zeolite4 Bench Test – Combinatorial & High Throughput Materials Science – DOE Award DE-FC26-05NT42415

SCR-HC Improved 4

12

SummarySummaryTechnical case for US LD diesels is improvingMajor innovation is underway

What will it take for wide-spread US LD Diesels?Continued technical progressMarket demand

Continued energy supply pressurePublic experience with new clean diesels

Technical case for US LD diesels is improvingMajor innovation is underway

What will it take for wide-spread US LD Diesels?Continued technical progressMarket demand

Continued energy supply pressurePublic experience with new clean diesels

Thank you for your attention

GM R&D Center