2 gdi engine development acc to eu 6 - avl

GDI engine development according EU 6

AVL SEMINAR, Oliver Fritz

2

EmissionEU-1 EU-2 EU-3 EU-4 EU-5a EU-5b EU-6

1992 1996 2000 2005 2009 2011 2014

Moderate Reduction (<30%) Large Reduction (>30%)

CO

PositiveIgnitionEngines(Gasoline)

2720 2200 2300 1000 1000 1000 1000

HC 200 100 100 100 100

NMHC 68 68 68

HC + NOx 970 500

NOx 150 80 60 60 60

PM only GDI 5 4,5 4,5

PN 6E12

mg/km

mg/km

mg/km

mg/km

mg/km

mg/km

#/km

2720 1000 640 500 500 500 500

970 560 300 230 230 170700

500 250 180 180 80

140 80 50 25 5 4,5 4,5

6E11 6E11

CO

CompressionIgnitionEngines(Diesel)

HC + NOx

NOx

PM

PN

mg/km

mg/km

mg/km

mg/km

#/km

Light duty emissions legislationEU Limits

3

PM-PN correlation

Grey solid symbols are data from the PMP light duty inter-laboratory exercise with the light duty golden instrument (Rotating disk type from Matter Eng.). Colored open symbols are data with APCs at various laboratories. Each point is a different vehicle or a different fuel (exception for D (DPF) PMP, which is the golden vehicle, all labs results are given). D=Diesel, DPF=Diesel Particulate Filter, MPI=Multi Point Injection, G-DI=Gasoline Direct Injection, LPG=Liquefied Petroleum Gas.

Comparison of the PN with the regulated PM emissions for different heavy duty engine technologies. Grey solid symbols are data from the PMP heavy duty inter-laboratory exercise with the heavy duty Golden instrument (SPCS prototype). Colored open symbols are measurements with APCs at JRC and AVL. Each point is a different engine or test cycle. DOC=Diesel Oxidation Catalyst, DPF=Diesel Particulate Filter, SCR=Selective Catalytic Reduction for NOx.

Giechaskiel et al. 2010, MST, in press.

No correlationNo correlation

4AVL P. Hollerer, VDI Forum Stuttgart 2010-12-070 100 200 300 400

Part

icu

late

nu

mb

er

[#]

Reduction of particulate number emission of GDI engines by calibration

EU6 –PN Limit proposal 6,0 E12#/km

time

0

500 600 700 1100 1200

SP

EE

D [km

/h]

0

60

120

What are the Challenges for EU6 emission calibration?

� EU6: New emission target for PN

� Find new strategies for PN reduction

� HW definition and combustion layout PN optimized

� Implementation of new functionalities for PN

� Update calibration process, methods and measurement equipment for particulates

800 900 1000

5AVL P. Hollerer, VDI Forum Stuttgart 2010-12-07

OutletInlet Spark plug

Injector MPI

InsideMixture formationOutside ��

��

� Differences MPI vs. GDI

Soot is a phenomenon of insufficient preparation of the air-fuel mixture.

It occurs mainly at direct injection engines, due to less time for homogenization.

OutletInlet

Injector GDI

Spark plug

Particulate generation

Wall fuel film:

MPI � manifold GDI � in Cylinder


Simulation:� Charge motion� Mixture preparation � Wall film

Combustion Layout:� Injector � Piston� combustion chamber design� Charge motion…

Calibration:� Base settings� Injection strategies� Catalyst heating strategy� Fuel pressure…

EU 6

Advanced Measurement Technology

Test EnvironmentMethods

Reduction of particulate number emission of GDI engines by calibration - Way to meet EU6 requirements



Microsoot Sensor

Particle counter

Opaci-meter

PNPM

Emission Bench

VisioFEM Gasoline

Visio

Measurement Technology

AdvancedEmissionMeasurementTechnology





EU 6





Effect of Injector HW and injection strategy on PN results

s

PN influence on injecting mode

Catalst heating idle test@1200Upm / BMEP 1bar

0,0E+00

5,0E+05

1,0E+06

1,5E+06

2,0E+06

2,5E+06

3,0E+06

2-times 3-times 4-times

Pa

rtic

ula

te N

um

be

r P

N[#

/cm

^3

]

Injektor A Standard EU4

Injektor B Optimierung 1

Injektor C Optimierung 2

Injector potentials

Optimized 1

Optimized 2





EU 6





Calibration strategies

0-200s200-1180s

0-200s200 -1180s

Part

icu

late

Nu

mb

er,

#

0 200 400 600 800 1000 1200

Time [sec]

Total share of Particle Result in NEDC Phases

EU IV EU VI


0 100 200 300 400 500 600 700 800 900 1000 1100 1200recorder_tim e [s]

SP

EE

D [

km

/h]

0

40

80

120

FRP 0.4 MPa FRP 15 MPa FRP 4 MPa FRP 8 MPa

Decreasing droplet sizeIncreasing evaporation

Increasing penetration

Penetration & Fuel Evaporation at Cold Start, OP: ~250rpm - First injection

�Cold start



COMBUSTION QUALITY


DOI 0.4 ms

DOI 0.8 ms

DOI 1.2 ms

Cold Start, Increasing DOI at Very High FRP, OP: ~250rpm - Last injection

Marks from Injector spray

NO marks from injector spray

0 100 200 300 400 500 600 700 800 900 1000 1100 1200recorder_tim e [s]

SP

EE

D [

km

/h]

0

40

80

120

�Cold start



0 100 200 300 400 500 600 700 800 900 1000 1100 1200recorder_tim e [s]

SP

EE

D [

km

/h]

0

40

80

120

Particulates >23 nm in tailpipe exhaust

�Cold start injection strategy – Multiple injection


Single Injection

Double Injection

Triple Injection

Quadruple Injection

Time - s

0 5 10 15 20 25

Part

icu

late

Nu

mb

er

–p

/ccm


�Catalyst heating (base settings)

� Catalyst heating idle test @1200rpm (cooled liquids – water&oil 20°)

EOI

last injectionlate earlier

BF

SC

, T

HC

, N

Ox,

CO

OP, F

SN

, P

N, P

M

Particle mass

Particle number

Filter smoke number

Opacity

EOI sweep

0 100 200 300 400 500 600 700 800 900 1000 1100 1200recorder_tim e [s]

SP

EE

D [

km

/h]

0

40

80

120



Part

icu

late

Nu

mb

er,

#

-70%EU6 –PN Limit proposal

Evaluation of Different Measures (NEDC)

0 200 400 600 800 1000 1200

Time [sec]

Baseline GDI TCI Euro4

Current status(Opt. only by calibration)

add.: Combustion system optimization

Current status (incl. HW mod.)

Opt. step 1


18

How does the sample point influence the particle size?

Dilution air

conditioning

Vehicle

exhaust

gas

Full dilution tunnel

1

2

PM

3

Heater

0.0E+00

5.0E+07

1.0E+08

1.5E+08

2.0E+08

2.5E+08

10 100 1000

Mobility Diameter [nm]

dN

/dlo

gD

p [

cm

-3]

Tailpipe

Sampling

End

anaconda

CVS 12m3/min

CVS 6 m3/min

120 kmh

1.2.

3.

Measurements with a hot FPS (Dekati) + SMPS (TSI)

Isella et al. 2008, JAS, 39, 737

19

Particle formation

20

Reduction of particle number in the exhaust duct

21

Two ways to measure the particles a GDI engine

AVL Micro Soot Sensor

AVL Particle Counter

22

Three ways to measure the particles of a GDI engine

Photo acoustic principle

- Able to detect very low soot values

- dynamic measurement signal specially for dynamic testrun

development

- R&D only (except HDIUC in USA)

Light scattering (particle counting)

- legislative requirement of solid particle measurement

- dynamic measurement

Filter Smoke Method (FSN)

- only for steady state application (R&D only)

23

Measurement methode AVL Micro Soot Sensor

24

0.00

0.20

0.40

0.60

0.80

1.00

1.20

1.40

1.60

1.80

0 200 400 600 800 1000 1200

Zeit [s]

Ru

ß [

mg

/cm

3]

0.00

0.04

0.08

0.12

0.16

500 600 700 800 900 1000 1100

Zeit [s]

Ru

ß [

mg

/cm

3]1,6L GDI Cold Start

Measurement results on GDI engines with MSS

Cold Start Tests

Especially for the transient optimization MSS is a suitable tool

Because the high sensitivity the MSS can be used to measure soot emissions of GDI engines

25

Measurement Methode AVL Particle Counter

Evaporation Tube

Dilution Tunnel (CVS)

PND1PNC: Particle

Number Counter

PND2

VPR: Volatile Particle Remover

Dilution air in To critical flow venturi

C HEPA

Particle number diluter 2

Particle number diluter 1

>23nm

Condensation Particle Counter (CPC) for particle counting

AVL Primary Diluter PND1

or

26

APC – MEASUREMENT RESULTS

0.0E+00

5.0E+10

1.0E+11

1.5E+11

2.0E+11

2.5E+11

3.0E+11

3.5E+11

4.0E+11

4.5E+11

5.0E+11

1 111 221 331 441 551 661 771 881 991 1101

0.0E+00

5.0E+12

1.0E+13

1.5E+13

2.0E+13

2.5E+13

GDI [#/s] MPI [#/s] GDI [#] MPI [#]

0.00

60.00

120.00

1 111 221 331 441 551 661 771 881 991 1101

SPEED km/h

27

Correlation of PN - PM

Euro 5: 4.5 mg/km and 6x10^11 p/km � 5x10^12 p/km

Euro VI: 10 mg/kWh and 6-8x10^11 p/kWh � 1x10^13 p/kWh

Giechaskiel et al. 2012, AST in press

28

0

2

4

6

8

10

12

14

16

18

20

0 500 1000 1500 2000 2500 3000 3500 4000 4500 5000

t [s]

so

ot

[mg

/m3]

0.0E+00

1.0E+07

2.0E+07

3.0E+07

4.0E+07

5.0E+07

6.0E+07

7.0E+07

8.0E+07

PN

C [

#/c

m3]

415S soot conc mg/m3

MSS soot conc mg/m3

APC #/cm3

Soot mass VS Particle number VS FSN @ GDI singlecylinder research engine

29

Correlation of PN - BC

For R&D PN systems have to be used

Or MSS has to measure close at its detection limit

Giechaskiel et al. 2012, AST in press

30

0.001

0.01

0.1

1

10

1.0E+08 1.0E+09 1.0E+10 1.0E+11 1.0E+12 1.0E+13 1.0E+14

Particle number [#/km]

So

ot

[mg

//km

]

Detection limit of MSS

Soot mass VS Particle number compared with different NEDC cycles


Summary

EU 6 defines PN limits for GDI engines

Reaching this limits without particle filter is possible if proper hardware is used and

calibration is done

Proper measurement equipment is required in order to detect the low soot as well as the

number

- Soot measurement (R&D applications)

- Particle counting (for number of particles, legislative requirement)

Measurement technique needs to be combined with proper optimization methods

With intelligent application strategies EU 4 Hardware PM emissions can be already

majorly reduced

Comparison between number and soot mass exists

2 gdi engine development acc to eu 6 - avl

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