aeronet workshop berlin, 16-17 sep 2002 leonidas ntziachristos mech. eng, phd post-doc research...

Aeronet Workshop

Berlin, 16-17 Sep 2002

Leonidas Ntziachristos

Mech. Eng, PhD

Post-Doc Research Fellow

SamplingSampling

& Instrumentation & Instrumentation TechniquesTechniques

for Automotive Exhaust for Automotive Exhaust Particle EmissionsParticle Emissions

Aeronet WorkshopBerlin,

16-17 Sep 2002

The “PARTICULATES

”

project team

” PARTICULATES „ Characterisation of Exhaust Particulate

Emissions From Road Vehicles

A 5 FP European research programmesponsored 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) ConsultantsJRC (NL) D. Kittelson G. Reischl


16-17 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%) http://vergina.eng.auth.gr/mech/

lat/particulates


16-17 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


16-17 Sep 2002

Nature of ICEExhaust Particles

Primary particles Soot - elemental carbon

(mostly on diesel engines) Heavy HC (PAHs, >C20)

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


16-17 Sep 2002

Size definitions and

morphology

(diesel engine)

Df~3Df~3

Df~2.4Df~2.4

+secondary particles


16-17 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- 1992: 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


16-17 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


16-17 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


16-17 Sep 2002

Issue 1

What to measure

Instruments

(most widespread techniques - non exhaustive list)

Metric Technique Property Size RangeSize

ResolutionTime

ResolutionRemarks

Mass Filter Method Total mass <10 um None None Standard method for PM determination

ImpactorMass / aerod.

Diameter~20 nm -

10 um10 - 15 stages

None Small size range is problematic

TEOMTotal mass of

solids< 10 um None s

Only suitable where solids dominate

Number CPC Total number > 3 nm None s Can be reference

instrument for total number

Number & size

SMPSNumber, mobility

diameter 7 nm - 1 um

64 channels per decade

min

Mobility relevant for small sizes, most

widespread technique

ELPINumber,

aerodynamic diameter

7 nm - 10 um

14 size bins s

Aerodynamic relevant for

accumulation, most suitable for solids

SurfaceEpiphanio-

meterFuchs surface > 7nm None s

Until lately the only technique for on-line

surface determination

Diffusion charger

"Active" surface > 7nm None sCheap altenative to

epiphaniometer

ChemistryAnalytical

techniquesChemical

informationNone

Standard chemical analysis, time consuming

Depending on classification method

Aerosol Mass Spectrometer

Size, chemical information

30 nm - 3 um

10 part / s sState of the art high-

cost application


16-17 Sep 2002

How do exhaust aerosol looks

like after atmospheric

dilution?

Data from SAE 2000-01-2212, Kittelson et al.


16-17 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

0.E+00

2.E+08

4.E+08

6.E+08

8.E+08

1.E+09

1.E+09

1.E+09

1 10 100 1000

electrical mobility particle diameter dp [nm]

dN

/dlo

g d

p [

cm-3

] 40 °C

30 °C

19 °C

17 °C

Dilution Parameter: Temperature

0.0E+00

5.0E+08

1.0E+09

1.5E+09

2.0E+09

2.5E+09

3.0E+09

1 10 100 1000


dN

/dlo

g d

p [

cm-3

]

41

24

15

Dilution ratio

Dilution Ratio

0.0E+00

5.0E+08

1.0E+09

1.5E+09

2.0E+09

2.5E+09

1 10 100 1000


dN

/dlo

g d

p [

cm-3

]

0.6 s

3.1 s

Residence time

Residence Time

0.0E+00

5.0E+08

1.0E+09

1.5E+09

2.0E+09

2.5E+09

1 10 100 1000


dN

/dlo

g d

p [

cm-3

]

50

38.8

26

14.4

10

2.4

relative humidity [%]of dilution air

RH of dilution air


16-17 Sep 2002

Issue 2

How to measure

Vehicle effects

Vehicle Effect: THC concentration

0.0E+00

5.0E+07

1.0E+08

1.5E+08

2.0E+08

2.5E+08

3.0E+08

3.5E+08

4.0E+08

4.5E+08

5.0E+08

1 10 100 1000


dN

/dlo

g d

p [

cm-3

] 506

390

238

99.2

25

13.6

THC concentration ofdilution air [ppm]

0.0E+00

5.0E+08

1.0E+09

1.5E+09

2.0E+09

2.5E+09

1 10 100 1000


dN

/dlo

g d

p [

cm-3

]

250 ppm

<10 ppm

Sulphur content of fuel

Sulphur concentration

0.0E+00

2.0E+08

4.0E+08

6.0E+08

8.0E+08

1.0E+09

1.2E+09

1 10 100 1000


dN

/dlo

g d

p [

cm-3

]

0 min.

3 min.

6.5 min.

10 min.

13.5 min.

16.5 min.

Consecutive SMPS scans

History effects


16-17 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: 12.5:1DT: 32°C

RT: 1 ms+stabilisation

(~3s)


16-17 Sep 2002

SamplingConfiguration

Example: Diesel engine

emissions

Ageing Chamber

2-stage ejector Dilutor

Dilution Air Line

Sample Line

Silica Gel

CharcoalFilter

EjectorDilutor

Heater Denuder

Mass Flow

Controller

ELPI

SMPS

Diffusion

Charger

Cooling Agent Line

Fdddg kjlk

TEOM

DR 12 : 1DR 12 : 1T 30 - 40°CT 30 - 40°C

RT 1 msRT 1 ms

Pump

Throttle Valve

Grav. Impactor

DR 120 : 1DR 120 : 1T ambT amb

RT 2.5 sRT 2.5 s

DR 1200 : 1DR 1200 : 1T ambT amb

RT 2.8 sRT 2.8 s

DR 120 : 1DR 120 : 1T 40°CT 40°C

RT 3.5 sRT 3.5 s

S A M P L E IN

D IL U T E D S A M P L E O U T


16-17 Sep 2002

Example of properties

determinationin 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


16-17 Sep 2002

Example of protocol

application

Motorcycle emissions

-400

-200

0

200

400

600

800

0 200 400 600 800 1000 1200

ECE 40 Cycle Time [s]

Ac

tiv

e S

urf

ac

e [

cm

2 s-1

]

0

20

40

60

80

100

120

Sp

ee

d [

km

h-1

]

Yamaha BWS (3.2 m²/km).

.

Speed

Yamaha BWS

1.E+07

1.E+08

1.E+09

1.E+10

1.E+11

1.E+12

1.E+13

0 200 400 600 800 1000 1200ECE 40 Cycle Time [s]

dN

/dlo

gD

p [

s-1

]

0

30

60

90

120

150

180

Sp

ee

d [

km

h-1

]

Total particles, 100 nm mob.Solid particles, 104 - 168 nm aer.

Speed

.

.Honda DIO

1.0E+10

1.0E+11

1.0E+12

1.0E+13

1.0E+14

1.0E+15

1.0E+16

1.0E+17

1 10 100 1000Mobility Diameter [nm]

dN

/dlo

gD

p [

km

-1]

55 km/h

20 km/h

Active SurfaceConcentration of totals/solidsDistribution with nucleation mode

Honda DIO

1.0E+08

1.0E+09

1.0E+10

1.0E+11

1.0E+12

1.0E+13

1.0E+14

1.0E+15

1.0E+16

1.0E+17

1 10 100 1000 10000

Aerodynamic Diameter [nm]

dN

/dlo

gD

p [

km

-1]

20 km/h

55 km/h

Solid particles distribution


16-17 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?

aeronet workshop berlin, 16-17 sep 2002 leonidas ntziachristos mech. eng, phd post-doc research...

Documents

fuel quality

fuel ca

exhaust aerosol properties

massbased measures

massbased method

aristotle university

medical research

fuel additives ce