Ground measurements on aircraft exhaust for a series of alternative jet fuels during the ECLIF and ND-MAX campaign

> ETH Conference 2018 > Tobias Schripp • ECLIF/ND-MAX > 19.06.2018DLR.de • Chart 1

Tobias Schripp, Patrick Oßwald, Markus KöhlerDLR Institute of Combustion Technology, Chemical AnalyticsPrem Lobo, Joel C. Corbin, Gregory SmallwoodNational Research Council of CanadaEwan Crosbie, Claire Robinson, Michael ShookNASA Aerosol Research Group

Emission & Climate Impact of Alternative Fuels (ECLIF)> ETH Conference 2018 > Tobias Schripp • ECLIF/ND-MAX > 19.06.2018DLR.de • Chart 2

2014 NASA-DLR Collaboration (DLR participating in NASA ACCESS (Alternative Fuel Effects on Contrails and Cruise Emissions) II)

2015 ECLIF Part 1: Impact of aromatic content in alternative fuels. Contrailmeasurements and ground measurements compared to fossil Jet A-1 (Falcon –A320 „ATRA“)

2018 ECLIF Part 2: Ground measurements and in-flight emissions & contrailsmeasurements of HEFA blends with special focus on naphthalene content(NASA DC-8 – A320 „ATRA“)

ECLIF Ground Measurements Setup> ETH Conference 2018 > Tobias Schripp • ECLIF/ND-MAX > 19.06.2018DLR.de • Chart 3

A320 / V2527-A5 engines Two sampling probes (left/right engine), 30 m Ground measurement after each flight (no

„warm-up“ artifacts or residual fuels) Two complementary sets of aerosol analytics

by NASA and DLR with CPCs, EEPS, SMPS, etc.

NASA

„Switch Box“

DLR-VT

Engine 1

Engine 2

SSJF1 SSJF2 SSJF3 FSJF

Con

tent

[mas

s%]

0

20

40

60

80n-Paraffinsiso-Paraffinsmonocyclic-Paraffins

bicyclic-Paraffinspolyclic-ParaffinsAlkylbenzenes

cyclo-Alkylbenzenesbicyclic-Aromatics

vol% aromatics8 10 12 14 16 18 20

H/C

ratio

1.90

1.92

1.94

1.96

1.98

2.00

2.02

2.04

2.06

ECLIF Fuels> ETH Conference 2018 > Tobias Schripp • ECLIF/ND-MAX > 19.06.2018DLR.de • Chart 4

Two reference Jet A-1 (~18 v% aromatics; H/C ratio ~1.923) Four alternative jet fuels: fully synth. jet fuel (FSJF) and semi-synth. jet fuel 1-3

Same aromatic content~11 v% and H/C ~ 2.03

15 v%1.954

9 v%1.981

SSJF1/2

Reference

SSJF3

FSJF

One alternative jet fuelwith low aromatics but high H/C ratio (FSJF)

H/C ratio

1.92 1.94 1.96 1.98 2.00 2.02 2.04

Parti

cle

mas

s em

issi

on in

dex

[mg/

kg]

0

100

200

300

400

Aromatic compounds [m%]

8 10 12 14 16 18

Parti

cle

mas

s em

issi

on in

dex

[mg/

kg]

0

100

200

300

400

FSJF

SSJF2

SSJF1

SSJF3

Ref1

Ref1/Ref2

SSJF3

FSJF

SSJF1

SSJF2Ref2

ECLIF Emission indices – Aromatics vs. H/C ratio> ETH Conference 2018 > Tobias Schripp • ECLIF/ND-MAX > 19.06.2018DLR.de • Chart 5

Emission index development does not strictly follow the aromatic content but theH/C ratio

Significant trend can be observed at high power settings (> 70% N1)

High power setting

Low power setting

High power setting

Low power setting

Fuel flow [kg/h]0.21 0.32 0.71 0.91

Red

uctio

n in

PM

inde

x co

mpa

red

to R

ef1

[%]

-60

-40

-20

0

Ref2SSJF1SSJF2SSJF3FSJF

ECLIF Conclusion and lessons learnt> ETH Conference 2018 > Tobias Schripp • ECLIF/ND-MAX > 19.06.2018DLR.de • Chart 6

Significant reduction of emittedparticle mass (soot) for thedifferent fuel blend

Fuel flow [kg/h]0.0 0.2 0.4 0.6 0.8 1.0

Parti

cle

num

ber e

mis

sion

inde

x [#

/kg]

4e+15

5e+15

6e+15

7e+15

8e+15

9e+15

1e+16Left engineRight engine

The duration for each power setting(1 min) was not ideal for SMPS (nvPM) measurements

Difference between both engines (l/r) was too high

→ Improved in the follow-upcampaign

ND-MAX/ECLIF Fuels> ETH Conference 2018 > Tobias Schripp • ECLIF/ND-MAX > 19.06.2018DLR.de • Chart 7

Jet A-1 (Ref3)• “high“ aromatics (~ 19 v%)• “high“ naphthalene content

Jet A-1 (Ref4)• “low“ aromatics (~ 15 v%)• “low“ naphthalene content

Reference fuels / blending components

(≤ 100 ppm sulfur)

HEFA-SPK(no aromatics)

Sust. alternative jet fuel 1 (SAJF1)Ref3-blend

Sust. alternative jet fuel 2 (SAJF2)Ref4-blend

Blending goals• same aromatics (~ half of ref. fuels)• different naphthalene content

Sust. alternative jet fuel 3 (SAJF3)(intermediate properties)

Can we measure a difference in sootemissions between SAJF1 and SAJF2?

These combinations give insightinto the impact of naphtalenecontent on the soot formation

ND-MAX/ECLIF Setup> ETH Conference 2018 > Tobias Schripp • ECLIF/ND-MAX > 19.06.2018DLR.de • Chart 8

A320 (ATRA) at 40 m distance from blast fence (probe position) Exhaust analysis performed by 6 science groups from a central manifold Instruments covered different types of particle counters and soot monitors (CPCs,

EEPS, LII, CAPS, etc.)

The weather conditions in Jan 2018 were different from ECLIF (Sep 2015) Improved duration of stable power settings led to improved statistics despite non-

ideal weather conditions

Time [min]

0.0 0.2 0.4 0.6 0.8 1.0 1.2 1.4 1.6

CO

2 [p

pm]

400

600

800

1000

1200

1400

1600

1

2

3

45 8

976*

Time [min]0.0 0.2 0.4 0.6 0.8 1.0 1.2 1.4 1.6

PNC

[#/c

m³]

0

5e+4

1e+5

2e+5

2e+5

ND-MAX/ECLIF Test matrix> ETH Conference 2018 > Tobias Schripp • ECLIF/ND-MAX > 19.06.2018DLR.de • Chart 9

No. N1 [%] t [min]1 23 8 Taxi

2 82 3 Climb

3 23 3 Taxi

4 75 75 60 86 53 8 Approach

7 40 88 60 89 23 8 Taxi

60 min test run for eachfuel

Comparison to LTO cyclesettings via fuel flow

Fuel flow [kg/s]0.3 0.4 0.5 0.6 0.7 0.8 0.9 1.0

Parti

cle

mas

s em

issi

on in

dex

[mg/

kg]

0

100

200

300

400

500

600

700

800

Ref3Ref4SAJF1

SAJF2SAJF3

DRAFT

ND-MAX/ECLIF Emission indices> ETH Conference 2018 > Tobias Schripp • ECLIF/ND-MAX > 19.06.2018DLR.de • Chart 10

The dependence of sootemission on fuel flow is similarto the previous campaign

Particle size distribution shiftedto larger particles than ECLIF part 1

Particle diameter [nm]

10 100

dN/d

logD

p

0.0

2.0e+4

4.0e+4

6.0e+4

8.0e+4

1.0e+5

1.2e+5

1.4e+5

dM [µ

g/m

³]

0.0

0.2

0.4

0.6

0.8

1.0

Particle numberParticle mass

The results of the different research groupsare currently consolidated!

Ref4

ND-MAX/ECLIF EIs – Aromatics vs. H/C ratio> ETH Conference 2018 > Tobias Schripp • ECLIF/ND-MAX > 19.06.2018DLR.de • Chart 11

H/C ratio1.86 1.88 1.90 1.92 1.94 1.96 1.98 2.00 2.02 2.04

Parti

cle

mas

s em

issi

on in

dex

[mg/

kg]

200

400

600

8000.37 kg/s0.45 kg/s 0.77 kg/s0.89 kg/s

Ref3

Ref4

SAJF3

SAJF1

SAJF2

Aromatic compounds [v%]8 10 12 14 16 18 20

Parti

cle

mas

s em

issi

on in

dex

[mg/

kg]

200

400

600

8000.37 kg/s0.45 kg/s 0.77 kg/s0.89 kg/s

SAJF1

SAJF2

SAJF3

Ref3

Ref4

Trend in emission indices follows the observations in ECLIF part 1

The emission indices of SAJF3 are associated with higher uncertainties (weatherconditions, non-ideal alignment); further analysis necessary

DRAFT DRAFT

ND-MAX/ECLIF EIs – Aromatics vs. H/C ratio> ETH Conference 2018 > Tobias Schripp • ECLIF/ND-MAX > 19.06.2018DLR.de • Chart 12

H/C ratio1.86 1.88 1.90 1.92 1.94 1.96 1.98 2.00 2.02 2.04

Parti

cle

mas

s em

issi

on in

dex

[mg/

kg]

200

400

600

8000.89 kg/s

Ref3

Ref4

SAJF3

SAJF1

SAJF2

Aromatic compounds [v%]8 10 12 14 16 18 20

Parti

cle

mas

s em

issi

on in

dex

[mg/

kg]

200

400

600

8000.89 kg/s

SAJF1

SAJF2

SAJF3

Ref3

Ref4

Highest power setting („climb“) provides insight into the dependencies

Sub-component composition beyond aromatics is a relevant feature for futureresearch

“ High“ naphtalenecontent

“ Low“ naphtalenecontent (~1/10)DRAFT DRAFT

Conclusions & Outlook> ETH Conference 2018 > Tobias Schripp • ECLIF/ND-MAX > 19.06.2018DLR.de • Chart 13

The data sets from both campaigns provide unique insight into the impact ofalternative fuels on soot emission

Reductions of soot emission in the range of 60-70 m% can be achieved by thedescribed fuel blends

The H/C ratio is a feasible indicator for jet engine soot emission; the details in chemical composition may result in small biases though Relevant for future fuel design activities Follow-up GCxGC analysis of ND-MAX/ECLIF fuels

Combination with cloud data and atmospheric particle concentrations (contrailmeasurements) will allow quantifying the reduction potential under flightconditions (→ climate effects, particle/cloud interactions)

> ETH Conference 2018 > Tobias Schripp • ECLIF/ND-MAX > 19.06.2018DLR.de • Chart 14

The ground team thanks Transport Canada for additional funding.

ECLIF/ND-MAXGround

Measurement Team

Thank you for youattention!