Diesel Passenger Car Technology for Low Emissions and CO2 ... · NZED: Integration of combustion,...

www.ricardo.com© Ricardo plc 2009

Diesel Passenger Car Technology for Low Emissions and CO2

Compliance

DEER 2009

Brian Cooper

Ricardo plc

2© Ricardo plc 2009

Diesel engine technology will contribute to the fuel economy improvement of future US light duty vehicles

Cost effective reduction of legislated emissions (including CO2

) is a major issue. NOx control must not be a limiting factor to the long term success of Diesel engines

Promising ultra low NOx and NMHC emissions have been achieved through the integration of combustion, air and aftertreatment developments

New Diesel technology offers extremely low NOx potential and good fuel economy if key issues regarding robustness, aging and OBD can be successfully resolved


LEV2 Diesel challenge

FTP-75 Drive Cycle Targets

0.00

0.20

0.40

0.60

0.80

1.00

1.20

0.00 0.10 0.20 0.30 0.40 0.50

NOx (g/mi)

NM

HC

(g/m

i)

Typical E4 engine out & tailpipe emissions

Typical E4 vehicle:engine out & tailpipe

emissionsAFTERTREATMENT

ENGINE OUT EMISSIONS

TYPI

CA

L E4

AFT

ERTR

EATM

ENT

T2B5 (120k)

~85% NOx reductionfrom ECT for T2B5

Fuel spec:-

45 Cetane index-

13 ppm S


0.00

0.20

0.40

0.60

0.80

1.00

1.20

0.00 0.10 0.20 0.30 0.40 0.50

NOx (g/mi)

NM

HC

(g/m

i) SULEV Diesel challenge

ENGINE OUT EMISSIONS

T2B2 (120k)

T2B5 (120k)

>95% NOx reduction from ECT

High catalyst heating results in fuel and oil dilution penalties

Increased aftertreatment cost

FTP-75 Drive Cycle Targets~85% NOx reduction from ECT

Increased engine HC

Reduced exhaust temperature

AFTE

RTRE

ATM

ENT

ENGINE OUT EMISSIONS REDUCTION

AFTERTREATMENT

TYPI

CA

L E4

AFT

ERTR

EATM

ENT


NZED: Integration of combustion, air and aftertreatment developments to target future emissions goals

3500 lb ITW Mid Size Passenger Car

6 speed conventional auto transmission

1.9 litre in line 4 cylinder DOHC 16v

Production 1600 bar 2nd

generation FIE

New two-stage series-sequential turbocharging and hybrid EGR system

Ricardo air/EGR path, combustion and aftertreatment control strategy

New integrated aftertreatment system (LNT + DPF)


Benefits of air, EGR, combustion and control technology

NEW AIR, EGR & CONTROL TECHNOLOGY

IMPROVED POWER, TORQUE AND

TRANSIENT BOOST RESPONSE

HIGHLY PRE-MIXED COOL COMBUSTION

LOW CHARGE O2 CONC. LEAN COMBUSTION OPTIMISED TIMING

AVOID MISFIRE NO MODE SWITCHING CONTROL INLET TEMP.

ENABLE DOWNSPEEDING AND LOWER CO20.0

0.1

0.2

0.3

0.4

0.5

0.6

0.0 0.2 0.4 0.6 0.8 1.0BMEP [MPa]

BS S

oot [

g/kW

h]

0

50

100

150

200

250

300

350

400

Pre-

mix

Fac

tor [

%]

0

10

20

30

40

50

60

70

EG

R R

ate

[%]

Euro 4Level 2Level 3

Pre-mix factor = [Ignition delay/ Injection duration] x 100

100% -

fully pre-mixed

2000 rev/min ExampleReference: 2009 Stuttgart

Symposium

ULTRA LOW NOx, LOW SOOT AND CO2


The aftertreatment system has been integrated into the engine design to target SULEV NMHC compliance

Pre turbo catalysts for low NMOG

Small LNT due to low absolute NOx mass reduction required

All catalysts on hot side of engine

Increase in PGM (E4 to T2B2)–

Cost increase of $360 (based on PGM prices 22/7/09)

ExhaustManifold

2L

2.5L

0.6L PTC2

Zone CoatedDOC & LNT

ccDPF

HP VGT

LP VGT

0.1L PTC1

ExhaustManifold

VGT

λ

λ

NOx

TYPICALE4

NZED AFTERTREATMENTSYSTEM

~0.5LDOC

~2LDOC~2.5LcDPF


FTP-75 temperatures with no forced heating strategy

Time [s]1000 1100 1200 1300 1400 1500 1600 1700 1800 1900 2000

Exh

aust

Tem

ps [°

C]

050

100150200250300350400450500550

Exhaust Manifold PTC2 Inlet

Exh

aust

Tem

ps [°

C]

050

100150200250300350400450500550

0 100 200 300 400 500 600 700 800 900 1000

veh02_818007_ftp75a_070709veh02_818007_ftp75b_070709

PTC1 light-off within 30sPTC2 light-off within 50s

600s soak

period



Time [s]1000 1100 1200 1300 1400 1500 1600 1700 1800 1900 2000

Exh

aust

Tem

ps [°

C]

050

100150200250300350400450500550

Exhaust Manifold PTC2 Inlet PTC2 Outlet

Exh

aust

Tem

ps [°

C]

050

100150200250300350400450500550

0 100 200 300 400 500 600 700 800 900 1000

veh02_818007_ftp75a_070709veh02_818007_ftp75b_070709

600s soak

period

Exotherm over PTC2



Time [s]1000 1100 1200 1300 1400 1500 1600 1700 1800 1900 2000

Exh

aust

Tem

ps [°

C]

050

100150200250300350400450500550

Exhaust Manifold PTC2 Inlet PTC2 Outlet LNT Inlet

Exh

aust

Tem

ps [°

C]

050

100150200250300350400450500550

0 100 200 300 400 500 600 700 800 900 1000

veh02_818007_ftp75a_070709veh02_818007_ftp75b_070709

600s soak

period

LNT temperature 200-300°C with no active heating strategy applied


0.00

0.20

0.40

0.60

0.80

1.00

1.20

0.00 0.10 0.20 0.30 0.40 0.50

NOx (g/mi)

NM

HC

(g/m

i)

PTC

DOC/

LNT/

DPF

Typical E4 engine out & tailpipe emissions

Typical E4 vehicle:engine out & tailpipe

emissions TYPI

CA

L E4

AFT

ERTR

EATM

ENT

NZED FTP-75 Emissions Status

0.00

0.02

0.04

0.06

0.08

0.10

0.00 0.02 0.04 0.06 0.08NOx (g/mi)

NM

HC

(g/m

i)

Tailpipe vehicle resultLNT regenerated during

pre-conditioning. No rich spikes applied

during FTP-75 testT2B2(120k)

T2B5(120k)

T2B3(120k)

New calibration optimised for lower NMHC in Phase 1


94% tailpipe NOx reduction overall relative to typical E4: 76% from engine and additional 76% from LNT

Time [s]

0 100

200

300

400

500

600

700

800

900

1000

1100

1200

1300

1400

1500

1600

1700

1800

1900Sp

eed

[kph

]

0306090

Cum

ulat

ive

NO

x [g

]

012345

NO

x M

ass

Flow

[g/s

]

0.0000.0050.0100.0150.0200.0250.0300.0350.040

Euro 4 Baseline Vehicle NZED Vehicle - Exhaust Manifold NZED Vehicle - Tailpipe

LNT 68%DeNOx

LNT 92%DeNOx

LNT 60%DeNOx


Time [s]

0 100

200

300

400

500

600

700

800

900

1000

1100

1200

1300

1400

1500

1600

1700

1800

1900Sp

eed

[kph

]

0306090

Cum

ulat

ive

NM

HC

[g]

03691215

NM

HC

Mas

s Fl

ow [g

/s]

0.0000.0050.0100.0150.0200.0250.0300.0350.040

NZED Vehicle - Exhaust Manifold NZED Vehicle - Tailpipe

99.6%

Exceptional aftertreatment performance is required to achieve SULEV levels of NMHC


Catalysts subject to 8h oven aging at 800°C

PTC subject to 200h running test bed & vehicle

LNT/DPF subject to 30h running in vehicle

CVS dilution ratio reduced to improve accuracy

4-6 mg/mi tailpipe NMHC observed during repeat testing

FTP-75 - Phase 3

0.00.20.40.60.81.01.21.41.6

Engineout

Post PTC Post DPF

Hyd

roca

rbon

s (g

/mi)

FTP-75 - Phase 2

0.00.20.40.60.81.01.21.41.6

Engineout

Post PTC Post DPFH

ydro

carb

ons

(g/m

i)

NONMHC

NONMHC

52%

51%

FTP-75 - Phase 1

0.0

0.2

0.4

0.6

0.8

1.0

1.2

1.4

1.6

Engine out Post PTC Post DPF

Hyd

roca

rbon

s (g

/mi) CH4

NMHC

48%

96%

98%

FTP-75 - Combined

0.00.20.40.60.81.01.21.41.6

Engineout

Post PTC Post DPF

Hyd

roca

rbon

s (g

/mi) 99.6%51%

99%

NZED emissions presents challenges for measurement system capability


Time [s]305 306 307 308 309 310

Tailp

ipe

CH

4 / N

MH

CM

ass

Flow

[g/s

]

0.000

0.004

0.008

0.012

0.016 Calculated Lambda CH4 Mass Flow NMHC Mass Flow

Cal

cula

ted

Lam

bda

0.8

1.0

1.2

1.4

1.6

Next step: application of rich spike to increase NOx conversion while minimising NMHC penalty

Low NMHC rich spike calibration

<1 mg/mi NMHCincrease per spike

0.00

0.02

0.04

0.06

0.08

0.10

0.00 0.02 0.04 0.06 0.08NOx (g/mi)

NM

HC

(g/m

i)

T2B2(120k)

Next step: apply low HC rich spike strategy

T2B5(120k)

T2B3(120k)

Tailpipe result(No rich spikes)


Cost Reduction

Integrated engine design

Optmised catalysts with reduced PGM loading

Decontent engine technology

Significant issues must be resolved for SULEV Diesel vehicles to become practical

Emissions Robustness

Low NOx DPF Regeneration

OBDUltra low NOx US06 threat

Source:

New combustion system

Catalyst durability development

Combustion control R&D

EGR system fouling research

O2 calibration optimisation

Application of exhaust fuel injection and fuel reforming technology

New control algorithms

New and improved sensors

Optimised aftertreatment strategy

SULEVDIESEL?

Time [s]0 100 200 300 400 500 600

LNT

Inle

t Tem

pera

ture

[°C

]

100

150

200

250

300

350

NZED strategy gives lowNOx and optimal LNT temp.


20

25

30

35

40

0.00 0.10 0.20 0.30 0.40 0.50

FTP-75 NOx (g/mi)

Labe

l Fue

l Eco

nom

y (m

i/gal

)The NZED approach offers fuel economy benefits by improving efficiency and reducing aftertreatment heating

Production2L Turbo Gasoline

ECODIESEL

TECHNOLOGY

Potential Fuel Economy and Emissions

Typical E4 vehicle (with DPF)

Typical T2B5 position~5% FE penalty due to aftertreatment heating







DIESEL IS NOT ON THE MAT!

Diesel Passenger Car Technology for Low Emissions and CO2 ... · NZED: Integration of combustion,...

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Transcript of Diesel Passenger Car Technology for Low Emissions and CO2 ... · NZED: Integration of combustion,...