Diesel Emissions TestingDiesel Emissions TestingAsian Vehicle Emission Control Conference 2004Asian Vehicle Emission Control Conference 2004

Terry L. UllmanTerry L. UllmanSouthwest Research InstituteSouthwest Research Institute®®

Office of Automotive EngineeringOffice of Automotive EngineeringApril 27April 27--29, 200429, 2004China World HotelChina World Hotel

Beijing, ChinaBeijing, China

Southwest Research Institute®Southwest Research Institute®

Emission Testing RequiresEmission Testing Requires

•• Defined Processes to:Defined Processes to:Generate EmissionsGenerate EmissionsSample and Quantify Pollutant EmissionsSample and Quantify Pollutant Emissions

Process to Generate EmissionsProcess to Generate Emissions

Engine TestEngine Test, , Mass Pollutant/Work PerformedMass Pollutant/Work Performed•• Variety of Applications Variety of Applications –– Truck, Nonroad Equipment, etc.Truck, Nonroad Equipment, etc.•• Engine Only Engine Only –– Must SupplyMust Supply

Fuel, Air, Cooling, Load, Exhaust SystemFuel, Air, Cooling, Load, Exhaust System•• Specific Test CycleSpecific Test Cycle

-- SteadySteady--State PointsState Points-- Transient CycleTransient Cycle

TorqueMeter

Fuel Engine DynamometerLoad

Air

Process to Generate EmissionsProcess to Generate EmissionsVehicle TestVehicle Test, , Mass Pollutant/Distance TraveledMass Pollutant/Distance Traveled•• Special Purpose Special Purpose –– Cars, Buses, etc.Cars, Buses, etc.•• Integrated System Integrated System –– Natural Gas, Hybrid, etc.Natural Gas, Hybrid, etc.•• Engine Driveline, Fuel, Exhaust System, Cooling, Air Engine Driveline, Fuel, Exhaust System, Cooling, Air

HandlingHandling•• Chassis Dynamometer, Specific Inertia, Road LoadChassis Dynamometer, Specific Inertia, Road Load•• Specific Driving CycleSpecific Driving Cycle

DynamometerLoad

Fuel

Air

TorqueMeter

Engine

Process to Sample and Quantify Process to Sample and Quantify PollutantsPollutants

•• Concentration of PollutantConcentration of Pollutant•• Mass of ExhaustMass of Exhaust•• Distance or WorkDistance or Work•• SteadySteady--StateState

-- Sample Raw ExhaustSample Raw Exhaust-- Measure Air & Fuel, Fuel + COMeasure Air & Fuel, Fuel + CO22, ,

Direct MeasureDirect Measure-- Distance, km or Work, kWDistance, km or Work, kW--hrhr

SteadySteady--State Test CycleState Test CycleISO 8178 ISO 8178 –– C1 CycleC1 Cycle

Speed (%)

40 60 80 100

Load

(% a

t spe

ed)

0

25

50

75

100 15%

15%

15%

15%

10%

10%

10%

10%

Inte

rmed

iate

Spe

ed

Idle

SteadySteady--State Test CycleState Test CycleEuropean Stationary Cycle (ESC)European Stationary Cycle (ESC)

SteadySteady--State TestingState TestingFixed Flow ExhaustFixed Flow Exhaust•• Not Limited by Engine SizeNot Limited by Engine Size•• Raw Sample for Gaseous Raw Sample for Gaseous

(HC, CO, NO(HC, CO, NOxx, CO, CO22))•• Partial Sample DilutedPartial Sample Diluted

for Particulate (PM)for Particulate (PM)

D ynam om eterLoad

Fue l

A ir

T orqueM ete r

E ng ine

S am ple P M

H eated F ilte r

H C C O N O C O 2

Transient TestingTransient TestingDo Engines Operate in SteadyDo Engines Operate in Steady--State Modes?State Modes?Generally NOT!Generally NOT!•• Several Recognized Transient CyclesSeveral Recognized Transient Cycles•• Engines CyclesEngines Cycles•• Vehicle Driving CyclesVehicle Driving Cycles

The HeavyThe Heavy--Duty Transient Cycle Duty Transient Cycle for On Roadfor On Road

0

20

40

60

80

100

120

NO

RM

ALI

ZED

TO

RQ

UE,

%

0 200 400 600 800 1000 1200 TIME, SECONDS

0

20

40

60

80

100

120

NO

RM

ALI

ZED

SPE

ED, %

0 200 400 600 800 1000 1200 TIME, SECONDS

Engine Test SetEngine Test Set--Up for SteadyUp for Steady--State and TransientState and Transient

CVS for Emissions with Variable Flow CVS for Emissions with Variable Flow Exhaust, TransientExhaust, Transient

Filter Pack

Engine

Gas Meter

Pump

Bag Sample

Gas Analyzer

Sample Line

Heated Line

90mm PM Filters

SampleZone

Heat Exchanger

CO, CO2, HC, and NOx Background Bag Sample PM

RawExhaustPipe

CO, CO2Sample Bag

NOxAnalyzer

HCAnalyzer Positive Displacement

Pump (PDP)

DilutionAir

10 DiametersMixingOrifice

Air

TorqueMeter

DynamometerLoad

Fuel

HeavyHeavy--Duty Vehicle Chassis DynoDuty Vehicle Chassis Dyno

•• Inertia SimulationInertia Simulation•• Single and Tandem AxlesSingle and Tandem Axles•• Road Load MatchingRoad Load Matching•• Driver’s Aid for CyclesDriver’s Aid for Cycles•• Full Flow CVSFull Flow CVS•• Emission BenchEmission Bench

Transient Vehicle CyclesTransient Vehicle Cycles

HD UDDS CycleHD UDDS Cycle

ETC TransientETC TransientCycleCycle

From: dieselnet.comFrom: dieselnet.com

Diesel Emission of THCDiesel Emission of THCTHC, Total Hydrocarbon Emission THC, Total Hydrocarbon Emission

•• Heated Flame Ionization DetectorHeated Flame Ionization Detector•• HH22 + Air + Air →→ FlameFlame•• Ionization Proportional to Carbon AtomsIonization Proportional to Carbon Atoms•• Sample Transfer at 375Sample Transfer at 375°°F, 190F, 190°°CC•• Heated FilterHeated Filter•• Overflow Calibration and SpanOverflow Calibration and Span•• Equal Response to Paraffins, Olefins, AromaticsEqual Response to Paraffins, Olefins, Aromatics•• Variation in Response to HC + OVariation in Response to HC + O22 or Nor N22 AtomsAtoms•• Linear ResponseLinear Response•• WetWet

Diesel Emission of THCDiesel Emission of THC

Diesel Emission of THCDiesel Emission of THC

Diesel Emission of NODiesel Emission of NOxxChemiluminescent Analysis of Nitrogen Oxides Chemiluminescent Analysis of Nitrogen Oxides

NONOx x == NONO22 + NO + NO

NONO22 Converted to NO,Converted to NO,NO + ONO + O33 →→ NONO22* * →→ NONO22 + hy + hy

NO Nitric OxideNO Nitric OxideNO + ONO + O33 →→ NONO22* * →→ NONO22 + + hyhy

Heated Sample Line 212Heated Sample Line 212°°F, 100F, 100°°CCWet or DryWet or Dry

Diesel Emission of NODiesel Emission of NOxx

Diesel Emission of PMDiesel Emission of PMPM, Total Particulate MatterPM, Total Particulate MatterGravimetric to 1 Gravimetric to 1 µµgg90, 70, 47 mm Filter Media, Two Filters90, 70, 47 mm Filter Media, Two FiltersFluorocarbon Coated GFFluorocarbon Coated GFSample Diluted, Sample Diluted, << 125125°°F, 52F, 52°°CCLoading 20 to 1000 Loading 20 to 1000 µµggDouble Dilution Double Dilution –– HDHDSingle Dilution Single Dilution -- LDLD

Diesel Emission of PMDiesel Emission of PM

19880.600.60

NONOxx, G/HP, G/HP--HRHR

0.100.10

0.050.05

0.250.25

2.52.5 33 44 55 66

Part

icul

ate,

G/H

PPa

rtic

ulat

e,G

/HP --

HRHR

11 22

1991

199419982002

(NOx + HC)StandardsStandards

For 2007/2010For 2007/2010

The Legislative Environment The Legislative Environment -- Regulations (HD)Regulations (HD)

Typical Diesel Engine Exhaust Particle Typical Diesel Engine Exhaust Particle Size DistributionsSize Distributions

00.020.040.060.08

0.10.120.140.160.18

0.001 0.010 0.100 1.000 10.000Diameter ( µm)

Nor

mal

ized

Con

cent

ratio

n,

dC/C

tota

l/dlo

gDp

Mass Weighting

Fine ParticlesDp < 2.5 µm

Ultrafine ParticlesDp < 100 nm

NanoparticlesDp < 50 nm

NucleiMode

Number Weighting

AccumulationMode

CoarseMode

PM10Dp < 10 µm

CARBON+OTHER OIL FUEL SO4

+H2

O

Particulate Matter Composition with Particulate Matter Composition with Engine Speed and LoadEngine Speed and Load

Carbon + Others Oil Fuel SO2-H2O

Physical and Chemical Characteristics of Physical and Chemical Characteristics of Particles Emitted from DieselParticles Emitted from Diesel

Soot Particles (Elemental Carbon, 10 nm to 20 nm in diameter)

Metallic Ash Particles Formed from Lube Oil (10 nm to 20 nm)

Hydrocarbon Particles (10 nm to 30 nm after growth)

Sulfuric Acid /Hydrocarbon ( 10 nm to 30 nm after growth)

Chain Agglomerate of Soot Particles (40 nm to 500 nm)

Chain Agglomerate of Soot Particles with adsorbed/condensed layers of hydrocarbon and sulfate and Metallic ash (40 nm to 500 nm)

Particle Size, Number, and Mass Particle Size, Number, and Mass of Engine Emissionsof Engine Emissions

•• Ultrafine and Nanoparticle Ultrafine and Nanoparticle Measurement Measurement

•• StateState--ofof--thethe--Art InstrumentsArt Instruments•• SteadySteady--State and Transient State and Transient

ApplicationsApplications•• PM Sampling Protocols PM Sampling Protocols

DevelopmentDevelopment•• Interpretation of Instrument Data Interpretation of Instrument Data

and Sampling Conditionsand Sampling Conditions•• Current and 2007 PM Sampling Current and 2007 PM Sampling

ProtocolsProtocols•• CVS and MicroCVS and Micro--Dilution SystemsDilution Systems•• Experimental and Theoretical Experimental and Theoretical

Particle Deposition AnalysisParticle Deposition Analysis

0

500

1000

1500

2000

2500

3000

0 300 600 900 1200

Time (seconds)

Eng

ine

Spe

ed (R

PM

1.0E+07

1.0E+08

1.0E+09

1.0E+10

1.0E+11

1.0E+12

1.0E+13

Par

ticle

Num

ber

Em

issi

oR

ate

(Par

t./se

c)

Engine Speed Particle Number

1.00E+05

1.00E+06

1.00E+07

1.00E+08

1.00E+09

1.00E+10

1 10 100 1000Dp (nm)

DN

/DLo

g D

p (P

art./

cm³) PRT~1000 ms

PRT ~230 ms

PRT ~100 ms

ELPI

SMPS

Particle Instruments for Engine Particle Instruments for Engine EmissionsEmissions

•• Scanning Mobility Particle Sizer (SMPS & nanoScanning Mobility Particle Sizer (SMPS & nano--SMPS)SMPS)•• Electrical Low Pressure Impactor (ELPI)Electrical Low Pressure Impactor (ELPI)•• Condensation Particle Counter (CPC)Condensation Particle Counter (CPC)•• Engine Exhaust Particle Sizer (EEPS)Engine Exhaust Particle Sizer (EEPS)•• Quartz Crystal Microbalance (QCM)Quartz Crystal Microbalance (QCM)•• Tapered Element Oscillating Microbalance (TEOM)Tapered Element Oscillating Microbalance (TEOM)•• MicroMicro--Orifice Uniform Impactor (MOUDI & nanoOrifice Uniform Impactor (MOUDI & nano--MOUDI)MOUDI)•• Solid Particle Measurement System (SPMS)Solid Particle Measurement System (SPMS)•• ElectroElectro--Spray Particle Generator (ESPG)Spray Particle Generator (ESPG)

Large Engine TestingLarge Engine Testing

• • Large Engine use SteadyLarge Engine use Steady--State OperationState Operation• • Gaseous EmissionGaseous Emission--Raw Exhaust AnalysisRaw Exhaust Analysis• • Particulate Emission Particulate Emission –– Partial Sample Partial Sample –– DilutedDiluted

Split and Dilute . . . . .Split and Dilute . . . . .

DynamometerLoad

EngineFuel TorqueMeter

Positive DisplacementPump (PDP)

Heat Exchanger

MixingOrifice

Sample PMCO

Air

HC NO CO2

DilutionAir

Nonroad Transient CycleNonroad Transient Cycle•• Tier 4 Nonroad EnginesTier 4 Nonroad Engines

–– SteadySteady--State TestingState Testing–– NotNot--toto--Exceed TestingExceed Testing–– Transient Cycle TestingTransient Cycle Testing–– Composite CycleComposite Cycle–– Smoke LimitsSmoke Limits

Composite Nonroad Transient Duty Cycle

Process to Sample and Quantify Process to Sample and Quantify Pollutants?Pollutants?

CVS Apparatus for Sampling TransientCVS Apparatus for Sampling Transient•• Accurate But Low Dilute ConcentrationsAccurate But Low Dilute Concentrations•• Too LargeToo Large

Gaseous Emissions Gaseous Emissions –– Real TimeReal Time•• Exhaust FlowExhaust Flow•• ConcentrationConcentration

Particulate Emission Particulate Emission –– Real Time Real Time –– Partial Flow Sampling SystemPartial Flow Sampling System•• Exhaust FlowExhaust Flow•• Raw Exhaust Proportional Sample for GravimetricRaw Exhaust Proportional Sample for Gravimetric

-- SteadySteady--State State –– AcceptedAccepted-- Transient Transient –– PendingPending

Sierra BGSierra BG--3/TDAC 3/TDAC (Transient Dilution Airflow Control)(Transient Dilution Airflow Control)

Horiba PartialHoriba Partial--Flow Dilution Tunnel Flow Dilution Tunnel MDLT 1300TMDLT 1300T

AVL Smart SamplerAVL Smart Sampler

SteadySteady--State vs TransientState vs Transient

EPA has Established Goals for Portable Diesel EPA has Established Goals for Portable Diesel OnOn--Vehicle Emission MeasurementVehicle Emission MeasurementSystems/DevicesSystems/Devices

InIn--Use TestingUse Testing•• Gaseous and Particulate EmissionsGaseous and Particulate Emissions•• Truck and BusTruck and Bus•• Nonroad EnginesNonroad Engines•• LightLight--Duty Vehicles and TrucksDuty Vehicles and Trucks

InIn--Use Vehicle Emission Use Vehicle Emission MeasurementMeasurement

•• Transient CapableTransient Capable•• Quantify Exhaust Mass + NOx ConcentrationQuantify Exhaust Mass + NOx Concentration

+ HC Concentration+ HC Concentration•• ParticulateParticulate

-- Special Challenge Special Challenge –– GravimetricGravimetric-- Proportional Raw Sample CaptureProportional Raw Sample Capture-- DiluteDilute-- Accumulate on FilterAccumulate on Filter-- Weigh FilterWeigh Filter-- Special Challenge Special Challenge –– ConcentrationConcentration-- Instrument for Size and NumberInstrument for Size and Number-- Correlate to Gravimetric, Subject of CRC ECorrelate to Gravimetric, Subject of CRC E--66 Project66 Project

InIn--Use Vehicle Emission Use Vehicle Emission Measurement (Cont’d)Measurement (Cont’d)

•• Define Engine LoadDefine Engine Load-- Estimate by OnEstimate by On--Board ComputerBoard Computer-- Fuel ConsumptionFuel Consumption-- COCO22

•• System Must be RobustSystem Must be Robust•• PortablePortable•• Low Power ConsumptionLow Power Consumption•• Test CycleTest Cycle

-- “The Real World”“The Real World”-- NotNot--toto--Exceed SteadyExceed Steady--State PointsState Points

Heavy-Duty Diesel Emission RegulationsNew Test Cycles, Steady-State 13-Mode

ESC + Not-To-Exceed (NTE)

0%

20%

40%

60%

80%

100%

120%

0% 20% 40% 60% 80% 100% 120% 140%Normalized Speed

Nor

mal

ized

Tor

que/

Pow

er

%torque%power

ESC

NTE

ESC 13-MODE TEST PTESC REGION

NTE REGION

SEMTECHSEMTECH--DD

SEMTECH PMSEMTECH PM--300300

Thank You,Thank You,

Terry L. UllmanTerry L. UllmanAssistant DirectorAssistant Director(210) 522(210) 522--26542654

tullman@swri.orgtullman@swri.org

www.oae.swri.orgwww.oae.swri.org