Aeronet Workshop Berlin, Sep 2002 Leonidas Ntziachristos Mech. Eng, PhD Post-Doc Research Fellow Sampling & Instrumentation Techniques for Automotive Exhaust Particle Emissions

Aeronet Workshop Berlin, Sep 2002 The “PARTICULATES” project team ” PARTICULATES „ Characterisation of Exhaust Particulate Emissions From Road Vehicles A 5 FP European research programme sponsored by the Directorate General on TRansport and ENergy Partners: Associate partners: Aristotle University (GR) – Coord. Renault (F) Concawe (B) INRETS (F) Volvo (S) Dekati (FIN) Tampere University (FIN) Stockholm Univ. (S) EMPA (CH) Athens Uni. (GR) AEAT (UK) TRL (UK) IFP (F) INERIS (F) AVL (AUT) LWA (UK) MTC (S) Graz University (AUT) Aachen University (D) Consultants JRC (NL) D. Kittelson G. Reischl

Aeronet Workshop Berlin, Sep 2002 The “PARTICULATES” relevant info  Project started April 2000  3-year duration (end March 2003)  Total cost: 3,6 M€, EU contribution: 2,5 M€ (70%)  culates

Aeronet Workshop Berlin, Sep 2002 The “PARTICULATES” targets  Definition of the exhaust aerosol properties which will be examined and evaluation of available measurement instruments and techniques  Development and introduction of a harmonised protocol for the definition of exhaust aerosol sampling conditions  Examination of the particulate emissions of current light duty vehicles and heavy duty engines  Investigation of the influence of engine technology, fuel quality and after- treatment on particulate emissions

Aeronet Workshop Berlin, Sep 2002 Nature of ICE Exhaust Particles  Primary particles  Soot - elemental carbon (mostly on diesel engines)  Heavy HC (PAHs, >C 20 )  Ash (metal oxides): Lube oil and fuel (Ca, Mg, Zn,...) Engine component wear (Fe, Cu, Cr, Al,…) Fuel additives (Ce, Fe, Cu, Mn,…)  Secondary particles  Sulphates (from S in fuel and lube oil)  Condensable organic material  Water

Aeronet Workshop Berlin, Sep 2002 Size definitions and morphology (diesel engine) Df~3 Df~2.4 +secondary particles

Aeronet Workshop Berlin, Sep 2002 Why do we need to shift from mass to other metrics?  Legislative, mass-based method seemed not to be sensitive enough for future vehicle technologies : 0.14 g/km, 2005: 0,025 g/km  Work by ISO, US and EU authorities increased sensitivity and reproducibility of traditional method  Evidence from medical research calls for a wider reporting of emissions  To better understand (and control) pollutant formation  Occasion: Report of HEI (1996) raised concerns that mass-based measures do not control number concentrations  evidence after that never confirmed such a finding in a consistent way

Aeronet Workshop Berlin, Sep 2002 Main Issues in ICE Particle Analysis  Issue 1: What to measure? … instrument  Particle property  Size range  Resolution (time, size)  Applicability / cost  Issue 2: How to measure? … sampling method  Dilution factor  Residence time  Temperature  RH  Hydrocarbon concentration of background air  Decisions to be taken on :  Requirements from health and environment experts  Potential for evaluation of technology measures

Aeronet Workshop Berlin, Sep 2002 Issue 1 What to measure Candidate Metrics  Mass of particles <10 μm (respirable fraction) is the legislation requirement  Size: Determines lung deposition profiles and cell interactions and behaviour in atmosphere  Aerodynamic diameter (> 100 nm)  Mobility diameter (< 100 nm)  Surface: Carrier of chemical species, medium for all interactions  Geometric  Fuchs  “Active” surface  Number: Sensitive metric to boundary condition changes  Nature/chemistry: Behaviour in atmosphere and in human body

Aeronet Workshop Berlin, Sep 2002 Issue 1 What to measure Instruments (most widespread techniques - non exhaustive list)

Aeronet Workshop Berlin, Sep 2002 How do exhaust aerosol looks like after atmospheric dilution? Data from SAE , Kittelson et al.

Aeronet Workshop Berlin, Sep 2002 Issue 2 How to measure Sampling Parameters  Dilution is required:  To avoid water condensation  To approach atmospheric process  Because particle concentration is usually above instrument max range Dilution Parameter:TemperatureDilution RatioResidence TimeRH of dilution air

Aeronet Workshop Berlin, Sep 2002 Issue 2 How to measure Vehicle effects Vehicle Effect:THC concentrationSulphur concentrationHistory effects

Aeronet Workshop Berlin, Sep 2002 Issue 2 How to measure Selection of sampling parameters  Similarity to atmospheric dilution  Potential to form nucleation mode  Small sensitivity to change of parameters  Feasibility to reach at the lab DR: 12.5:1 DT: 32°C RT: 1 ms+ stabilisation (~3s)

Aeronet Workshop Berlin, Sep 2002 Sampling Configuration Example: Diesel engine emissions Ageing Chamber 2-stage ejector Dilutor Dilution Air Line Sample Line Silica GelCharcoal Filter Ejector Dilutor Heater Denuder Mass Flow Controller ELPI SMPS Diffusion Charger Cooling Agent Line Fdddg kjlk TEOM DR 12 : 1 T °C RT 1 ms Pump Throttle Valve Grav. Impactor DR 120 : 1 T amb RT 2.5 s DR 1200 : 1 T amb RT 2.8 s DR 120 : 1 T 40°C RT 3.5 s

Aeronet Workshop Berlin, Sep 2002 Example of properties determination in a single run  Total “active” surface [RT]  Total particle number [RT]  Surface and number give mean size [RT]  Size segregated solid particle number [RT]  Solids particle mass [RT]  Gaseous pollutants [RT]  Particle mass (VF/nVF) - CVS [CYCLE]  Mass weighted size distribution [CYCLE]  Number weighted size distribution[SS]   RT: Real Time   CYCLE: Mean value over cycle   SS: Steady State

Aeronet Workshop Berlin, Sep 2002 Example of protocol application Motorcycle emissions Active SurfaceConcentration of totals/solidsDistribution with nucleation modeSolid particles distribution

Aeronet Workshop Berlin, Sep 2002 Conclusions Recommendations  Candidate metrics (automotive sector):  mass (will remain legislation metric)  active surface  total number concentration  accumulation mode profile  size segregated chemical fingerprints  Plume aerosol differs from engine-out one  Sampling parameters are critical if nucleation mode particles are important  Soot particles are easier to characterise (thermodenuders become widespread)  Experience from the automotive sector may also apply to ground-level aviation emissions  In-flight emissions?