06 avl india seminar may 2018 workshop testbed challenges …avl+india... · 2018-06-11 · 3xeolf...

$: 06 AVL India Seminar May 2018 Workshop Testbed Challenges …AVL+India... · 2018-06-11 · 3xeolf 'lhwhu )oruldq .xuw (qjhomhkulqjhu _ (plvvlrqv _ 0d\ _ 3duwlfxodwh 0dwwhu 30 0hdvxuhphqw$
AVL List GmbH (Headquarters)

Public

AVL India Seminar May 2018

Workshop:Emission on testbed: Bharat-VI Challenges

Dieter Florian

Kurt Engeljehringer

Dieter Florian, Kurt Engeljehringer | Emissions | May 2018 | 2Public

Emission Legislation

Introduction

Summary

ContentContent• Diesel, Gasoline

• PM + PN Measurement• Data Quality Aspects

BS 6 – Challenges for Emissions

Discussion

• LD, HD, NRMM


India: BS-VI challenges

Light Duty PC and CV• 2020 Bharat IV VI• 2020 RDE monitoring• 2023 RDE Limits (TA and COP)

Fuel consumption5.5 l/100km 4.7 l/100km

Gasoline:NOx: 80 60 mg/km moderatePM: 4.5 mg/km no problem, but large result scatteringPN: 6E11#/km moderate on testbed

Diesel:NOx: 180 80 mg/km De-NOx mandatoryPM: 25 4.5 mg/km requires DPFPN: 6E11#/km requires DPF

PN will be the leading limit, PM will automatically well below limit, but measurement will show high scattering

Fuel Quality!

RDE:clean under all “normal condition of use”Gasoline (GDI) challenge: GPF will be require, with complex implementationDiesel challenge: low NOx under all conditions

• EGR + LNT only very small engines (maybe)• EGR + SCR• EGR + LNT + SCR for larger and powerful vehicles


India: BS-VI challengesNew test procedures (GTR-4): much more to test

ESC WHSCETC WHTCNOX screening WNTE Random 15 mode test

In-Service compliance (PEMS) Off-Cycle emission compliance statement

Heavy Duty vehicles• 2020 Bharat-IV VI• UNR-49 GTR-4

Limits:HC: 0.55 0.16 g/kW-h -70%NOx: 3.5 0.46 g/kW-h -87%NH3: 25 10 ppm -60%PM: 0.03 0.01 g/kW-h -63%PN: new 6E11#/kW-h totally new

Full set of exhaust aftertreatment required, EGR, Oxi-Cat, DPF and SCR PN is becoming the leading particulate property. An engine fulfilling PN

will be well below the PM limit. SCR is a “chemical factory” in the vehicle, requires extensive nitrogen+

(NO, NO2, NOx, NH3) analysis via FTIR (AVL SESAM i60 FT).

Fuel quality: low sulfur fuel is mandatory!

Non-Road Mobile Machinery• Challenges will be quite the same

as for Heavy Duty• 2020 Bharat-III IV with GTR-11• 2023 Bharat-V with PEMS


Round Robin Results

Averag results of each labNr. Lab # of tests CO2 [g/km] CO [g/km] THC [g/km] NOx [g/km]

EU-6 Limits (130 target) 1,000 0,100 0,060

1 JARI-1 3 160,4 0,334 0,026 0,0082 NTSEL 3 164,4 0,328 0,036 0,0193 TOYOTA 3 156,8 0,313 0,019 0,0104 JARI-2 1 159,6 0,303 0,024 0,0085 ARAI 3 162,4 0,361 0,032 0,0126 NIER 4 163,9 0,263 0,025 0,0107 Kpetro (KEMCO) 3 158,3 0,382 0,028 0,0118 KATRI 3 163,5 0,373 0,030 0,012

AVG 23 161,2 0,332 0,028 0,011Delta min-max 5% 36% 62% 98%Standard deviation 2% 11% 18% 29%

WLTP Round Robin test in Europe and Asia 2015/2016:• Per region 2 “Golden” vehicles (Gasoline and Diesel)• All labs accepted for certification accordingly to UN-ECE Reg 83 and

prepared for WLTP• “Golden test engineer” • Outlier removed and statistical evaluation


Asian Round Robin: Diesel EU-4

AVE SD RSDg/km g/km %0.787 0.131 16.60.936 0.016 1.70.914 0.038 4.11.093 0.009 0.80.898 0.134 14.90.933 0.109 11.7

LMHxH

Lab. D 5Lab. E 3Lab. H 3Lab. A 2All data -Inter lab -

Labs# ofTest

0.00

0.20

0.40

0.60

0.80

1.00

1.20

La

b. D

La

b. E

La

b. H

La

b. A

NO

x (g

/km

)

LMHxH

NOx

PMLab. D 5Lab. E 3Lab. H 3Lab. A 2All data -Inter lab -

Labs# ofTest

AVE SD RSDmg/km mg/km %

24.2 1.4 5.922.9 0.4 1.820.9 2.9 13.721.8 1.6 7.422.8 2.2 9.722.4 1.2 5.5

LMHxH

10

15

20

25

30

35

La

b. D

La

b. E

La

b. H

La

b. A

PM

(m

g/k

m)

LMHxH

PNLab. D 5Lab. E 3Lab. H 3Lab. A 2All data -Inter lab -

Labs# ofTest

AVE SD RSD#/km #/km %

2.8E+13 1.2E+12 4.33.5E+13 4.1E+12 11.73.9E+13 4.1E+12 10.35.4E+13 1.1E+12 2.03.7E+13 9.1E+12 24.63.9E+13 9.3E+12 23.8

LMHxH

0.E+00

1.E+13

2.E+13

3.E+13

4.E+13

5.E+13

6.E+13

7.E+13

8.E+13

9.E+13

La

b. D

La

b. E

La

b. H

La

b. A

PN

(#

/km

)

LMHxH

NOx:• Reproducibility (Lab to Lab): 15 %• Repeatability (in Lab): 1 – 16%

PM: Note vehicle has no DPF• Reproducibility (Lab to Lab): 10 %• Repeatability (in Lab): 2 – 14 %• with lower emission (DPF) this numbers will go up

PN: Note vehicle has no DPF• Reproducibility (Lab to Lab): 25 %• Repeatability (in Lab): 2 – 12 %• with lower emission (DPF) this numbers will go up


WLTP Round Robin Tests (2015/2016)Gasoline vehicle• European Round Robin Test• BMW 116i

Mean SD RSD (%)

CO2 [g/km] 163 2.3 1.4

NOx [mg/km] 11 3.7 32.8

CO [mg/km] 335 61.2 18.2

HC [mg/km] 27 6.4 23.5

Asian RRT (Gasoline) - all data

• Asian Round Robin Test• Toyota WISH, 1.8l, 105kW, CVT

Mean SD RSD (%)

CO2 [g/km] 161 2.6 1.6

NOx [mg/km] 95 27.2 28.6

CO [mg/km] 456 67.9 14.9

HC [mg/km] 41 9.1 22.5

EU RRT (Gasoline) - all data

Diesel vehicle• European Round Robin Test• Alfa Romeo Giulietta with DPF

• Asian Round Robin Test• Mahindra XUV500, 2.2l, 103kW, 6MT, no DPF

Mean SD RSD (%)

NOx [mg/km] 291 35.7 12.3

CO [mg/km] 39 15.4 39.2

HC [mg/km] 8 3.7 46.2

PM [mg/km] 0.23 0.2 69.2

PN [#/km] 5.0E+11 1.3E+11 25.4

EU RRT (Diesel) - all data

CO2 [g/km] 3.2135 4.3

Mean SD RSD (%)

169 10.2 6.0

177 * 1.4 * 0.8 *

NOx [mg/km] 898 134.2 14.9

CO [mg/km] 235 66 28.1

HC [mg/km] 33 14.2 42.5

PM [mg/km] 23 2.2 9.7

PN [#/km] 3.7E+13 9.1E+12 24.6*) exclude Lab. D's data

CO2 [g/km]

Asian RRT (Diesel) - all data

Take away:

Inter Lab. Reproducibility

CO2: 2 – 4 %

CO: 15 – 40 %

HC: 20 – 45 %

NOx: 15 – 30 %

PM: 10 – 70 %

PN: 20 – 30 %


Challenges for PM/PN Emission Measurement


Particulate Matter (PM) MeasurementUncertainty Trend as factor of strengthened Limits

0

20

40

60

80

100

120

140

160

Euro-1/I Euro-2/II Euro-3/III Euro-4/IV Euro-5/V Euro-6/VI

PM Limits over time

LD PM Limit [mg/km] HD PM Limit [mg/kW-h]

Passenger cars and LD CV:• 140,0 mg/km Euro-1• 4,5 mg/km Euro-6

Heavy Duty Trucks and Busses:• 3,6000 g/kW-h Euro-I• 0,0010 g/kW-h Euro-VI

Measurement Uncertainty:• Signal to noise is decreasing significantly

Uncertainty

3600


Particulate Matter (PM) MeasurementComparison PFDS (SPC 478) vs. CVS (PSSi60)

Measurement Uncertainty for BS-6 increasing for low PM levels PN more robust compared to PM

PM equivalent when fulfilling the PN limit

Data Source: AVL

PN limit for EU 6 LD = 6*1011 #/km

PN mass equivalent ~ 0.4–0.5 mg/km PN mass ~ Faktor 10 < limit 4.5mg/km


Particulate Matter (PM) MeasurementReduction of Filter Mass & Change in PM Composition

EmissionLevel

Elementary Carbon

Condensed + absorbed

HC

Sulfates +

Nitrates

Other Artefacts

Comments

Euro 1, 2 +++ +++ - - Reduced emission by engine

optimization No exhaust aftertreatment

Euro 3, 4 +++ + + - HC and CO reduction by DOC DOC increases sulfate formation

Euro 5 - +++ +++ -

99% soot reduction by DPF HC and sulfates are still the same,

but are contributing relatively more to the total mass as before

Euro 6 - - - ++ Low sulfur fuel removes sulfates Complex SCR chemistry increases

other PM artefacts

EU 5/6 (BS-6) Improvements for existing Particulate Mass (PM) Procedure: HEPA & HC filtered air for exhaust dilution Cyclone pre-classifier Improved sample temperature control 47 +/-5°C Deletion of back-up filter (Artefact Trap!)


Particulate Matter (PM) MeasurementBest Praxis for robust BS-6 PM Measurement

BS-6 will force introduction of DPF / GPF:

PM values become ~10 times below the limit of 4.5mg/km

Measurement uncertainty will increase, however PM measurement still we stay manageable, since well below limit!

Improvement of existing BS-4 procedures required!1.0

0.0

0.5

2.0

3.0

4.0

4.5

Pa

rtic

ula

te M

as

s [

mg

/km

]

Limit 4.5 mg/km

Key Success Factors for robust BS-6 PM Measurement:

Clean dilution system (CVS or PFDS) background!

Highest dilution air quality (HEPA, HC, humidity) background!

Always use small filter size (47mm) less artefacts!

Proper filter handling is crucial transfer/conditioning/weighing!

Use of automated systems for filter handling + weighing!


Particle Number – What is it about?PN procedure acc. UN-ECE R83 implemented with Euro5/2007

Measurement ProcedureMeasurement ProcedureCVSCVS

1. Cyclon removes particles > 2.5µm2. Dilution + Conditioning removes

particles < 23nm3. Sensor counts particles in the range

of 23nm – 2.5µm Complex calibration procedure

1. Cyclon removes particles > 2.5µm2. Dilution + Conditioning removes

particles < 23nm3. Sensor counts particles in the range

of 23nm – 2.5µm Complex calibration procedure

Chassis DynoChassis Dyno

11

11

Dilution and Conditioning

22

22

Sensor

33

33


Particle Number – What is it about?PN procedure acc. UN-ECE R83 implemented with Euro5/2007


Challenges for PN – CALIBRATIONUN-ECE-R83 (Rev. 5) + UN-ECE-R49 (Rev. 6)

Dilution & Condtioning

Filt

er

Soot SourceSoot Source Size ClassifierSize Classifier ReferenceReference

Core SensorCore Sensor

AVL Calibrationacc. ISO 17025

Soot SourceSoot Source Size ClassifierSize Classifier ReferenceReference

Calibration Boundary Conditions

No standard materials for re-calibration at testbed Complex procedure for aerosol measurement specified Facility for radioactive equipment + skilled operators

Consequences: Yearly Re-Calibration by qualified Lab required! Expected PN Uncertainty > Gas Measurement!

Calibration Boundary Conditions

No standard materials for re-calibration at testbed Complex procedure for aerosol measurement specified Facility for radioactive equipment + skilled operators

Consequences: Yearly Re-Calibration by qualified Lab required! Expected PN Uncertainty > Gas Measurement!


Expected PN - Measurement UncertaintiesBased on international Round Robin experience

References: • Giechaskiel et al; SAE 2010-01-1299• Vogt et al, 14th ETH Conference, Zürich,

August 1-4th 2010• Giechaskiel et al; Aerosol Science and

Technology, 46:719–749, 2012• Inter Laboratory Correlation Exercise, JRC 2015• Giechaskiel et al. 2010, MST, 21, 045102• AVL interne Messdaten

Uncertainty for thePMP - Reference Methode

for PN – Type Approval

Uncertainty for thePMP - Reference Methode

for PN – Type Approval

11 ±8%±8%

Instrument Repeatabilityat the same CVS AnlageInstrument Repeatabilityat the same CVS Anlage

22 ±15%±15%

Instrument Reproducibilityat the same CVSInstrument Reproducibilityat the same CVS

33±20-25%±20-25%

PNCPNC Testbed ReproducibilityDifferent Particle Counter and CVS Round Robin for TA @ testbed

Testbed ReproducibilityDifferent Particle Counter and CVS Round Robin for TA @ testbed

±20-30%±20-30%44

Additional Uncertainty for PNby different sampling positions CVS vs. Tailpipe

Additional Uncertainty for PNby different sampling positions CVS vs. Tailpipe

Uncertainty contributionto PN-PEMS correlation

RDE CF = 1.5

Uncertainty contributionto PN-PEMS correlation

RDE CF = 1.5


Correlation APC to PN-PEMSImpacting Factors for CF = 1.5

CF = 1,5:

±50% or±1E+11 [#/km]

CF = 1,5:

±50% or±1E+11 [#/km]

PN- PEMSDC oder CPC

PN- PEMSDC oder CPC

JRC conclusion: uncertaintyPN-PEMS/Tailpipe vs. PMP/CVSis maximum ±50%

CF = 1 + 50% Margin

Influencing factors: Sampling Position / losses uncertainty for PN Uncertainty exhaust mass flow Uncertainty vehicle speed

Re-evaluation of CF on a yearly basis

JRC conclusion: uncertaintyPN-PEMS/Tailpipe vs. PMP/CVSis maximum ±50%

CF = 1 + 50% Margin

Influencing factors: Sampling Position / losses uncertainty for PN Uncertainty exhaust mass flow Uncertainty vehicle speed

Re-evaluation of CF on a yearly basis

Reference @ CVS

PEMS sampling

50% Margin is already consumed by the Measurement Uncertainty of the PEMS method!!


Ensure Data Quality for PM/PNApplication Know-How + Enhanced Conditions Measurement


Impacting Factors for Accuracy on System LevelCertification Aspects - Calculation

Example based on: ECE/TRANS/180 - Annex 7 Calculations (WLTP, GTR-15, Euro-6d temp), some calculations might be slightly different depending on actual test bed configuration:

VmixCVS Volumedil. exhaust

PowerAnalyzer

RaRel. humidity

Pdsat. vap. pressure

PBatm. pressure

CeConcentrationDil. Exh. Cont

CeConcentrationDil. Exh. Bag

CddConcentrationDil. Air Bag

Concentrations, corrected [ppm]:

Dilution Factor

Fuel propertiesx, y, z

Fuel properties

Gaseous Mass Emissions [g/km]:Gaseous Mass Emissions [g/km]:

NOx humidity correction factor:

Specific humidity:

Particulate Mass Emission [mg/km]:Particulate Mass Emission [mg/km]:

Densities: Ρi@ 273.15 K (0 °C) and 101.325 kPa:

Carbon monoxide (CO) ρ=1.25 g/lCarbon dioxide (CO2) ρ=1.964 g/lNitrogen oxides (NOx) ρ=2.050 g/lHydrocarbons:

for petrol (E0) ρ=0.619 g/1for petrol (E5) ρ=0.632 g/1for petrol (E10) ρ=0.646 g/lfor diesel (B0) ρ=0.620 g/lfor diesel (B5) ρ=0.623 g/l……

Particle Number Emission [#/km]:Particle Number Emission [#/km]:

Flow-weighted average:

VepVolume@ filter

PNCC = PN conc.k, fr = factors

dDistancedriven

PePM mass

collected on filter

TimeValidation


Impacting Factors for Accuracy on System LevelCertification Aspects - Calibration and Maintenance

VmixCVS Volumedil. exhaust

PowerAnalyzer

RaRel. humidity

Pdsat. vap. pressure

PBatm. pressure

CeConcentrationDil. Exh. Cont

CeConcentrationDil. Exh. Bag

CddConcentrationDil. Air Bag

Fuel propertiesx, y, z

VepVolume@ filter

PNCC = PN conc.k, fr = factors

dDistancedriven

PePM mass

collected on filter

TimeValidation

• Distance• Torque• Velocity

Chassis Dyno

• Temperature• Barometric pressure• Humidity (Intake air)

Ambient climatic condition

• Wind speed / motor speed

Blower

• Current• Voltage

Power Analyzer

• CFV’s calibration• Pressure upstream CFV• Temperatur upstream CFV

CVS Full flow dilution

• Mass Flow Meter• PM Temperature

PM Particulate Sampler

• Linearity• Calibration gases

Gaseous Emission Bench

• CPC calibration• PN factor evaluations

PN Particle Counter

• Concentration certificates• Purity certificates• Traceability

Calibration and operation gases

• Weight• Filter conditioning• Filter handling

PM Particle Scale

Manual inputs are a common issue for problems, like wrong fuel parameters

Leaks are common issue for problems

Plausibility checks, result validation and result release procedures are important

Calibration and maintenance is crucial for low emission testing


Complexity for Aerosol Measurement

Multiple Compounds, Soot dominating PM

Different Technologies measure different Aerosol Fractions!

Temp., Press, humidity, loss Mechanisms for PN etc. need to be considered

Correlation of Particle Measurement DevicesAspects for Emission Aerosol Measurements in R&D

Application Know-How

Core-Sensor &Dilution / Conditioning / Samplingin-house Technology

Best Praxis Calibration Methodology

Empirical Correlation Experience see Product Application Guides


Tailpipe

Correlation of Particle Measurement DevicesAspects for Sampling Position

Engine out

8 Dilution Tunnel(CVS or PFDS)*

ExhaustAftertreatment

Engine

Certification

Light duty vehicles, R83Heavy duty engines, R49 Low Temperatures < 52°C Low Pressure Diluted, low concentrations Defined regulative procedure

Research and Development High temperatures up to 1000°C High pressures up to 1bar High PN/PM Concentrations Select appropriate Instruments Apply specific EO sampling kits Consider Correlation Aspects


Correlation between Soot Mass and PM/CVS

SAE 2012-01-1254

• Correlation between soot mass (BC, MSS) and PM (CVS) has already been demonstrated during the EPA Measurement Allowance Program for HD In-Use Compliance Testing

• On the Road validation with exhaust “doped” with bypass (PM ~30 mg/hphr)

• Robust Correlation• PM is app. 85% Soot• Depending on engine, vehicle, load etc.


Correlation between Soot Mass and PNImpact of Agglomeration Effects on PN

Correlation PN and Soot Mass (Black Carbon)Soot Measurement also correlates to PN (PMP) soot is the main contributor to “solid PN” pre-calibration by MSS final calibration by APC

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

mass

[mg

//km

]

Detection Limit MSS

Soot Mass vs. PN for NEDC

• PN concentration remains constant atlevels <107 p/cm3

• A concentration of 108 p/cm3 for 50 nm particles decreases by ~23% in 3sec.

• Agglomeration is not important for post-DPF or GDI applications

• At same time soot mass stays constant!


Task Application Conditions Test cell type MeasurementBase Calibration EAS Calibration -7°C – +30°C Engine Test bed

Chassis Dyno or PowertrainCVS, PTS, APC, AMAPre- and Post Cat AMAMSS

Cold start Cold StartHeat-up and Warm up strategy

Start test without driveoff,focus on +23°C

Engine Test BedVehicle (Cold start place)

Pre- & Post-Cat AMAAPCMSS

SCR SCR Layout and control strategyAdBlue injectionValidation of homogenous mixing

Full temperature range Engine test bed or powertrain Pre- & Post-Cat FTIR

GPF / DPF DPF / GPF Characterization stationary operationFilter loadingFilter regeneration

Engine Test Bed Pre- & Post-PF APCPre- & Post-PF MSSSmokeMeter or Opacimeter

Start & EOGPF and DPF calibration

EO emission ModelSmoke map (Diesel)PF filter loading modelNTE testsActive / Passive Regeneration

Dynamic Tests run temperatures down to -30°C (depending on OEM -25 to -40°C)

Chassis Dyno or Powertrain

In-vehicle

Pre- & Post-PF APCPre- & Post-PF MSS

PN-PEMSMSS

RDE Calibration Calibration in the wide engine map range RDERobustness evaluation

-7°C – +30°C (RDE Boundary)-30°C for AES ContinuityAltitude (0 – 1300 – 2400m)

Chassis Dyno or PowertrainSpecific RDE cyclesRoad-2-Lab approach

CVS, PTS, APC, AMAPre- and Post Cat AMAFTIRMSS

RDE Validation Robustness evaluation -7°C – +30°C (RDE Boundary)Altitude (0 – 1300 – 2400m)

Road PEMS

Passenger Car Calibration EU-6 + RDEOverview for Typical Testing Set-Up


Testing Tasks

GPF Characterization

1) Determination of pressure drop ΔP GPF

2) Determination of filtration efficiency η GPF

Regeneration Measurements

1) Continuous Regeneration

2) Regeneration in Fuel cut-off

GPF Verification Dyn/Cycle

3) Active increase of Passive Regeneration by GPF heating

CAT GPF Muffler

2×APC 2×MSS

CAT GPF Muffler

2×APC 2×MSS

Up to 3×AMA

1×AMA

Best praxis Application ExampleGasoline: GPF characterization on Testbed RDE

EU RDE PN-PEMS Gasoline

Targeting GPF introductionon GDI vehicles

GPF filtration efficiency < DPF

GDI Raw emissions + Filter Loading < Diesel

GDI Back-pressure sensitivity!

GDI Cold Start challenge!

Complex characterizationcompared to DPF


New Challenges for robust BS-6 Emission Measurement (Gaseous, PM, PN)

Control of impacting factors on Test System Level required

Ramp-up Operator Skills & Application Know-How

Data Quality

Frequent Instrumentation Maintenance + QA-checks

Yearly re-calibration for PN Instrumentation (APC + PN-PEMS) mandatory!

Standardization of Testbed set-ups for background reduction signal/noise

Benefit from AVL EU-6 implementation experience @ global customers

Proven test bed emission systems & -instrumentation solutions

Best praxis methodology support for specific application challenges

SUMMARY


Our Customer Emissionis our Mission

www.avl.com

06 avl india seminar may 2018 workshop testbed challenges …avl+india... · 2018-06-11 · 3xeolf...

Documents