Emission Testing Requires. Defined Processes to: Generate Emissions Sample and Quantify Pollutant Emissions

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1 Southwest Southwest Research Research Institute Institute Diesel Emissions Testing Asian Vehicle Emission Control Conference 2004 Terry L. Ullman Southwest Research Institute Office of Automotive Engineering April 27-29, 2004 China World Hotel Beijing, China

2 Emission Testing Requires Defined Processes to: Generate Emissions Sample and Quantify Pollutant Emissions

3 Process to Generate Emissions Engine Test, Mass Pollutant/Work Performed Variety of Applications Truck, Nonroad Equipment, etc. Engine Only Must Supply Fuel, Air, Cooling, Load, Exhaust System Specific Test Cycle - Steady-State State Points - Transient Cycle Air Fuel Engine Torque Meter Dynamometer Load

4 Process to Generate Emissions Vehicle Test, Mass Pollutant/Distance Traveled Special Purpose Cars, Buses, etc. Integrated System Natural Gas, Hybrid, etc. Engine Driveline, Fuel, Exhaust System, Cooling, Air Handling Chassis Dynamometer, Specific Inertia, Road Load Specific Driving Cycle Air Fuel Engine Torque Meter Dynamometer Load

5 Process to Sample and Quantify Pollutants Concentration of Pollutant Mass of Exhaust Distance or Work Steady-State State - Sample Raw Exhaust - Measure Air & Fuel, Fuel + CO 2, Direct Measure - Distance, km or Work, kw-hr

6 Steady-State State Test Cycle ISO 8178 C1 Cycle % 15% Load (% at speed) % Idle 10% 10% Intermediate Speed Speed (%) 15% 15% 10%

7 Steady-State State Test Cycle European Stationary Cycle (ESC)

8 Steady-State State Testing Fixed Flow Exhaust Not Limited by Engine Size Raw Sample for Gaseous (HC, CO, NO x, CO 2 ) Partial Sample Diluted for Particulate (PM) Heated Filter HC CO NO CO2 Sample PM Air Fuel Engine Torque Meter Dynamometer Load

9 Transient Testing Do Engines Operate in Steady-State State Modes? Generally NOT! Several Recognized Transient Cycles Engines Cycles Vehicle Driving Cycles

10 The Heavy-Duty Transient Cycle for On Road NORMALIZED TORQUE, % NORMALIZED SPEED, % TIME, SECONDS TIME, SECONDS

11 Engine Test Set-Up for Steady- State and Transient

12 CVS for Emissions with Variable Flow Exhaust, Transient HC Analyzer NOx Analyzer Positive Displacement Pump (PDP) Mixing Orifice 10 Diameters Dilution Air Filter Pack Raw Exhaust Pipe Sample Zone Heat Exchanger CO, CO2, HC, and NOx Background Bag Sample PM CO, CO2 Sample Bag Gas Meter Pump Air Bag Sample Gas Analyzer Fuel Engine Torque Meter Dynamometer Load Sample Line Heated Line 90mm PM Filters

13 Heavy-Duty Vehicle Chassis Dyno Inertia Simulation Single and Tandem Axles Road Load Matching Driver s Aid for Cycles Full Flow CVS Emission Bench

14 Transient Vehicle Cycles HD UDDS Cycle ETC Transient Cycle From: dieselnet.com

15 Diesel Emission of THC THC, Total Hydrocarbon Emission Heated Flame Ionization Detector H 2 + Air Flame Ionization Proportional to Carbon Atoms Sample Transfer at 375 F, 190 C Heated Filter Overflow Calibration and Span Equal Response to Paraffins, Olefins, Aromatics Variation in Response to HC + O 2 or N 2 Atoms Linear Response Wet

16 Diesel Emission of THC

17 Diesel Emission of THC

18 Diesel Emission of NO x Chemiluminescent Analysis of Nitrogen Oxides NO x = NO 2 + NO NO 2 Converted to NO, NO + O 3 NO 2 * NO 2 + hy NO Nitric Oxide NO + O 3 NO 2 * NO 2 + hy Heated Sample Line 212 F, 100 C Wet or Dry

19 Diesel Emission of NOx

20 Diesel Emission of PM PM, Total Particulate Matter Gravimetric to 1 µg 90, 70, 47 mm Filter Media, Two Filters Fluorocarbon Coated GF Sample Diluted, < 125 F, 52 C Loading 20 to 1000 µg Double Dilution HD Single Dilution - LD

21 Diesel Emission of PM

22 The Legislative Environment - Regulations (HD) Particulate,G/HP-HR HR Standards For 2007/ (NO x + HC) NO x, G/HP-HR HR

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24 Typical Diesel Engine Exhaust Particle Size Distributions Normalized Concentration, dc/c total /dlogdp Nuclei Mode Nanoparticles Dp < 50 nm Ultrafine Particles Dp < 100 nm Accumulation Mode Fine Particles Dp < 2.5 µm PM10 Dp < 10 µm Coarse Mode Diameter ( µm) Mass Weighting Number Weighting

25 Particulate Matter Composition with Engine Speed and Load Carbon CARBON+OTHER + Others Oil OIL Fuel FUEL SO 4 +H 2 -H 2 O

26 Physical and Chemical Characteristics of Particles Emitted from Diesel Soot Particles (Elemental Carbon, 10 nm to 20 nm in diameter) Chain Agglomerate of Soot Particles (40 nm to 500 nm) 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 with adsorbed/condensed layers of hydrocarbon and sulfate and Metallic ash (40 nm to 500 nm)

27 Particle Size, Number, and Mass of Engine Emissions Ultrafine and Nanoparticle Measurement State-of of-the-art Instruments Steady-State State and Transient Applications PM Sampling Protocols Development Interpretation of Instrument Data and Sampling Conditions Current and 2007 PM Sampling Protocols CVS and Micro-Dilution Systems Experimental and Theoretical Particle Deposition Analysis ELPI Engine Speed (RPM DN/DLog Dp (Part./cm³) 1.00E E E E E E Dp (nm) 1.0E Time (seconds) 1.0E E E E E E+08 SMPS PRT~1000 ms PRT ~230 ms PRT ~100 ms Particle Number Emissio Rate (Part./sec) Engine Speed Particle Number

28 Particle Instruments for Engine Emissions Scanning Mobility Particle Sizer (SMPS & nano-smps) Electrical Low Pressure Impactor (ELPI) Condensation Particle Counter (CPC) Engine Exhaust Particle Sizer (EEPS) Quartz Crystal Microbalance (QCM) Tapered Element Oscillating Microbalance (TEOM) Micro-Orifice Uniform Impactor (MOUDI & nano-moudi) Solid Particle Measurement System (SPMS) Electro-Spray Particle Generator (ESPG)

29 Large Engine Testing Large Engine use Steady-State State Operation Gaseous Emission-Raw Exhaust Analysis Particulate Emission Partial Sample Diluted

30 Split and Dilute..... Dilution Air Mixing Orifice Positive Displacement Pump (PDP) Heat Exchanger HC CO NO CO2 Sample PM Air Fuel Engine Torque Meter Dynamometer Load

31 Nonroad Transient Cycle Tier 4 Nonroad Engines Steady-State State Testing Not-to to-exceed Testing Transient Cycle Testing Composite Cycle Smoke Limits Composite Nonroad Transient Duty Cycle

32 Process to Sample and Quantify Pollutants? CVS Apparatus for Sampling Transient Accurate But Low Dilute Concentrations Too Large Gaseous Emissions Real Time Exhaust Flow Concentration Particulate Emission Real Time Partial Flow Sampling System Exhaust Flow Raw Exhaust Proportional Sample for Gravimetric - Steady-State State Accepted - Transient Pending

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

34 Horiba Partial-Flow Dilution Tunnel MDLT 1300T

35 AVL Smart Sampler

36 Steady-State State vs Transient EPA has Established Goals for Portable Diesel On-Vehicle Emission Measurement Systems/Devices In-Use Testing Gaseous and Particulate Emissions Truck and Bus Nonroad Engines Light-Duty Vehicles and Trucks

37 In-Use Vehicle Emission Measurement Transient Capable Quantify Exhaust Mass + NOx Concentration + HC Concentration Particulate - Special Challenge Gravimetric - Proportional Raw Sample Capture - Dilute - Accumulate on Filter - Weigh Filter - Special Challenge Concentration - Instrument for Size and Number - Correlate to Gravimetric, Subject of CRC E-66 E Project

38 In-Use Vehicle Emission Measurement (Cont d) Define Engine Load - Estimate by On-Board Computer - Fuel Consumption - CO 2 System Must be Robust Portable Low Power Consumption Test Cycle - The Real World - Not-to to-exceed Steady-State State Points

39 Heavy-Duty Diesel Emission Regulations New Test Cycles, Steady-State 13-Mode ESC + Not-To-Exceed (NTE) 120% 100% Normalized Torque/Power 80% 60% 40% ESC NTE 20% 0% %torque %power 0% 20% 40% 60% 80% 100% 120% 140% ESC 13-MODE TEST PT Normalized Speed ESC REGION NTE REGION

40 SEMTECH-D

41 SEMTECH PM-300

42 Thank You, Terry L. Ullman Assistant Director (210)