impact of ethanol and butanol as oxygenates on sidi engine ... · ethanol (c2h6o) acetaldehyde...

Impact of ethanol and butanol as oxygenates on SIDI engine efficiency and emissions using steady-state and transient test procedures

Thomas Wallner, Neeraj Shidore, Andrew IckesArgonne National Laboratory

16th Directions in Engine-Efficiency and Emissions Research (DEER) ConferenceDetroit, Michigan September 27-30, 2010

Acknowledgements

Co-Authors– Thomas Wallner

– Neeraj Shidore

Support and assistance from the Department of Energy– Connie Bezanson

– Lee Slezak

– Kevin Stork

– Gupreet Singh


2

Background & Motivation


3

0

3

6

9

12

15

18

21

2000

2002

2004

2006

2008

2010

2012

2014

2016

2018

2020

2022

Prod

ucti

on (B

Gal

./ye

ar) Ethanol

Advanced Biofuels

U.S. Renewable Fuel Standard requires an increase of ethanol and advanced biofuels to 36 billion gallons by 2022.

Iso-Butanol as possible advanced biofuel?

Adapted from: Renewable Fuels Standard (Federal Register, 75(58))

Objectives


4

Assess the potential of blending gasoline with several alcohol fuels for use in a gasoline direct injection (DI) spark ignition (SI) engine.

Evaluate the effect of ethanol and butanoladdition on regulated and non-regulated emissions compared to gasoline baseline.

Utilize Engine Hardware-In-Loop capability to characterize emissions trends over a simulated test cycle.

Fuel Specifications


5

Gasoline Ethanol iso-ButanolChemical formula C4 - C12 C2H5OH C4H9OHComposition (C, H, O) Mass-% 86, 14, 0 52, 13, 35 65, 13.5, 21.5Lower heating value MJ/kg 42.7 26.8 33.1Density kg/m3 715 - 765 790 802Octane number ((R+M)/2) - 90 100 103Stoichiometric air/fuel ratio - 14.7 9.0 11.2Latent heat of vaporization kJ/kg 380 – 500 919 686

Ethanol BlendsFuel Oxygen

(%-mass) Butanol Blends

E10 3.7 iso-But16E50 18 iso-But83

Constant oxygen mass content

Blend lower heating valuesGasoline: 42 MJ/kgE10/B16: 41 MJ/kgE50/B83: 35 MJ/kg

Experimental Methods – Steady State Testing


6

Opel 2.2 l Ecotec Direct (GM L850)

SIDI 4-Cylinder Engine, no VVA

ECU calibrated for gasoline

Emissions measurement

Horiba MEXA Model 7100D-EGR

AVL Sesam FTIR

Typical vehicle operating points

Constant speed

Constant load

Constant power

Engine-out (no TWC) emissions

Regulated Emissions


7

8

10

12

14

16

18

20

0 5 10 15 20

NO

xEm

issi

ons

(g/k

Whr

)

Oxygen Content (Mass-%)

Typical standard deviation less than 0.26 g/kWhr

Operating Points3000 rpm, 4 bar2000 rpm, 2 bar

1500 rpm, 2.62 bar2000 rpm, 6 bar3000 rpm, 8 bar1500 rpm, 8 bar

Ethanol blendsiso-Butanol blends

NOx decreases with increasing fuel alcohol and oxygen content

0%

10%

20%

30%

40%

50%

60%

70%

80%

90%

100%

Rel

ativ

e C

once

ntra

tion

(% v

ol.) Toluene (C7H8)

iso-Butanol (C4H10O)n-Butane (C4H10) Propene (C3H6)Ethanol (C2H6O)Acetaldehyde (C2H4O)Ethane (C2H6)Ethene (C2H4)Acetylene (C2H2)Formaldehyde (CH2O)Methane (CH4)0%

10%

20%

30%

40%

50%

60%

70%

80%

90%

100%

Rel

ativ

e C

once

ntra

tion

(% v

ol.) Toluene (C7H8)

iso-Butanol (C4H10O)n-Butane (C4H10) Propene (C3H6)Ethanol (C2H6O)Acetaldehyde (C2H4O)Ethane (C2H6)Ethene (C2H4)Acetylene (C2H2)Formaldehyde (CH2O)Methane (CH4)

Speciated Hydrocarbons (from FTIR)


8

1500 rpm, 2.62 bar BMEP

Formaldehyde Emissions


9

100

200

300

400

500

0 5 10 15 20Oxygen content (Mass-%)

HC

HO

Em

issi

ons

(mg/

kWh)

Typical standard deviation less than 14 mg/kWhr

Dec

reas

ing

Load

Operating Points2000 rpm, 2 bar

1500 rpm, 2.62 bar3000 rpm, 4 bar2000 rpm, 6 bar3000 rpm, 8 bar1500 rpm, 8 bar


Increased formaldehye with iso-butanol blends, but not with ethanol blends

Acetaldehyde Emissions


10

200

400

600

800

1000

1200

1400

0 5 10 15 20Oxygen content (Mass-%)

MeC

HO

Emis

sion

s (m

g/kW

h)

Typical standard deviation less than 32 mg/kWhr


Operating Points2000 rpm, 2 bar

1500 rpm, 2.62 bar3000 rpm, 4 bar3000 rpm, 8 bar2000 rpm, 6 bar1500 rpm, 8 bar

Dec

reas

ing

Load

Increased acetaldehye with both ethanol and iso-butanol blends

Engine Hardware-In-Loop Concept


11

AutonomieVirtual Vehicle

(dSPACE)

Speed, Torque

Throttle

Speed

Dynamometer

2005 Opel Vectra2.2 L Ecotec DI

Automatic (5-sp.)

NEDCCold/hot start

System ValidationCycle Fuel Consumption,

Emissions Mass, Species Behavior

Emissions sampling

Driving Cycle Engine ResponseEmissions &

Fuel EconomyVehicle Model

GasolineE50

Iso-But83

GasolineValidation

Experimental Methods: Engine HIL Testing


12

Vehicle Engine HIL

ECE-15 11.3 12.4

EUDC 6.1 6.5

NEDC 8.0 8.7

l/100km l/100km

Fuel ConsumptionEuro 4 Engine HIL

NOx > 0.1 0.02 ± 0.01

CO > 1 0.7 ± 0.2

HC > 0.068 0.03 ± 0.01

g/km g/km

Emissions

050010001500200025003000350040004500500055006000

-120-100

-80-60-40-20

020406080

100120

0 200 400 600 800 1000 1200

Engi

ne S

peed

(RPM

)

Sim

ulat

ed V

ehic

le

Spee

d (k

m/h

r)

Cycle Time (s)

0

2

4

6

8

10

12

14

16

NEDC ECE-15s EUDC

GasolineE50iso-But83

Vol.

Fuel

Con

sum

ptio

n (l/

100

km)

0

5

10

15

20

25

30

35

NEDC ECE-15s EUDC


Tota

l Ene

rgy

Con

sum

ptio

n (M

J)

Cycle Fuel and Energy Consumption


13

Hot-start cycles, integrated fuel flow

0.0

0.2

0.4

0.6

0.8

1.0

NOx THC CO

NED

C C

ycle

Em

issi

ons

(g/k

m) Gasoline

E50iso-But83

Euro IV Limit Euro IV

Euro IV Limit

Total Cycle Emissions Mass


14

NEDC, cold-start, post-TWC emissions

010002000300040005000600070008000

0 15 30 45 60

HC

Em

issi

ons

(ppm

)

Time (s)


Formaldehyde Emissions: Hot-Start, Pre-TWC


15

0

20

40

60

80

100

120

140

160

0 30 60 90 120 150 180

HC

HO

Em

issi

ons

(ppm

)

ECE-15 Cycle Time (s)

Gasoline E50 iso-But83

1st urban cycle of NEDC, hot-start, pre-TWC emissions

Formaldehyde Emissions: Cold-Start, Post-TWC


16

Gasoline E50 iso-But83Cycle mass HCHO emitted (mg/km) 1.5 2.0 7.0

0

5

10

15

20

25

30

35

40

0 200 400 600 800 1000 1200

HC

HO

Em

issi

ons

(ppm

)

Cycle Time (s)

0

5

10

15

20

25

30

35

40

0 10 20 30 40

HC

HO

Em

issi

ons

(ppm

)

Cycle Time (s)


Acetaldehyde Emissions: Hot-Start, Pre-TWC


17

0

50

100

150

200

250

300

350

0 30 60 90 120 150 180

MeC

HO

Emis

sion

s (p

pm)

ECE-15 Cycle Time (s)

Gasoline E50 iso-But83

1st urban cycle of NEDC, hot-start, pre-TWC emissions

0

50

100

150

200

250

300

350

400

450

0 200 400 600 800 1000 1200

MeC

HO

Em

issi

ons

(ppm

)

Cycle Time (s)

Acetaldehyde Emissions: Cold-Start, Post-TWC


18

Gasoline E50 iso-But83Cycle mass MeCHO emitted (mg/km) 10 40 110

050

100150200250300350400450

0 15 30 45 60

MeC

HO

Em

issi

ons

(ppm

)

Cycle Time (s)

GasolineE50isoBut83

Conclusions & Future Opportunities

Both ethanol and iso-butanol blends reduced cycle mass emissions of NOx and CO, and yield comparable cycle energy consumption.

Blends of gasoline and iso-butanol increase both acetaldehyde and formaldehyde emissions, while ethanol-gasoline blends increase acetaldehyde emissions, but not significantly formaldehyde.

Aldehyde emissions are eliminated in an active (warm) three-way catalyst: cycle aldehyde emissions stem from initial cold-start phase.

Improved cold-start engine operation with high-alcohol fuels (including iso-butanol blends) is critical for meeting emissions targets

Future exploration opportunities include particulate matter characterization from alcohol fuels utilizing engine HIL.


19


Thomas Wallner, Neeraj Shidore, Andrew IckesArgonne National Laboratory

16th Directions in Engine-Efficiency and Emissions Research (DEER) ConferenceDetroit, Michigan September 27-30, 2010

impact of ethanol and butanol as oxygenates on sidi engine ... · ethanol (c2h6o) acetaldehyde...

Documents