effect of driving conditions on nox emissions from 2010 ......regulatory class data source myg . hhd...

$: Effect of Driving Conditions on NOx Emissions from 2010 ......Regulatory Class Data Source MYG . HHD MHD LHD . BUS 1991-1997 . 19 - - 2 . RO\TER and 1998 . 12 - - - Consent Decree$
MOVES Motor Vehicle Emission Simulator

Effect of Driving Conditions on NOxEmissions from 2010+ Heavy-dutyVehicles Gurdas S. Sandhu, ORISE Fellow, US EPA Darrell Sonntag, US EPA Fakhri Hamady, US EPA

26th CRC Real-World Emissions Workshop, March 13-16, 2016, CA, USA

2

Scope

1. Variability in real-world duty cycles 2. Effect of exhaust temperature on NOx emissions 3. Do we need a different modeling approach for SCR equipped

vehicles?

Regulatory Class Data Source MYG HHD MHD LHD BUS

1991-1997 19 - - 2 RO\TER and

1998 12 - - -Consent Decree

1999-2002 78 30 25 -Testing 2003-2006 91 32 19 -2003-2006 40 25 15 -

HDIU 2007-2009 68 71 24 -1991-1997 8 - - -1998 1 - - -

Houston Drayage 1999-2002 10 - - -2003-2006 8 - - -

3

Motivation MOVES2014a NOx Data Sources

Table 2-2 (pg 16) , Exhaust Emission Rates for Heavy-Duty On-road Vehicles in MOVES2014, EPA-420-R-15-015a, November 2015 https://www3.epa.gov/otaq/models/moves/documents/420r15015a.pdf

https://www3.epa.gov/otaq/models/moves/documents/420r15015a.pdf

1200

1000 -

......... 800 -E

~

C. C. 600 ---- ◄

)(

0 ~ z 400 -

35300

- Pre-SCR

Post-SCR

I

35800

Idling == 34 m i1nutes

I I I

36300 36800 37300 Timestamp

37800 38300 ~

4

Motivation SCR Response Example 1 2010 MY, 13 liter, 450 hp, combination long-haul truck

5

Heavy-duty In-use Testing (HDIUT)

• Each year, US EPA selects some of the enginefamilies with production volume ≥ 1,500 units

• Manufacturers find vehicles from fleets that have the selected engine family

• Tests are conducted under real-world conditions using 1065 certified instruments

Relevant Regulation Citations: ― 40 CFR Part 86 Subpart T: Manufacturer-Run In-Use Testing Program for Heavy-Duty Diesel Engines. ― §86.007-11: Emission standards and supplemental requirements for 2007 and later model year diesel heavy-

duty engines and vehicles. ― §86.1370-2007: Not-To-Exceed test procedures. ― §86.1901: What testing requirements apply to my engines that have gone into service? ― §1065.915: PEMS instruments.

6

Test Data Description

ID Engine MY Disp (L) hp Odo (103 mi) Test Miles Test Secs Controls Application E1_T1 2010 15.0 475 246 266 23684 TC, CAC, EGR,

DPF, SCR-U Line Haul

E1_T3 475 268 330 30279 E1_T4 475 261 153 27034 E1_T5 475 324 258 39344 E2_T1 E2_T2 E2_T3 E2_T4 E2_T5

2012 16.0 525 575 525 525 525

78 127 153 107 166

394 253 322 317 393

38039 TC, CAC, EGR, 31685 DPF, SCR-U, 39021 AMOX 33742 36670

Line Haul

E3_T1 2011 10.5 380 321 489 34241 TC, CAC, EGR, DPF

Delivery E3_T2 400 205 190 23744 E3_T3 380 206 325 34290 E3_T4 400 131 191 35622 E3_T5 2011 15.0 450 184 432 33474 TC, CAC, EGR,

DPF Delivery

TC: Turbocharger | CAC: Charge Air Cooler | EGR: Exhaust Gas Recirculation | DOC: Diesel Oxidation Catalyst DPF: Diesel Particulate Filter | SCR-U: Selective Catalytic Reduction using Urea | AMOX: Ammonia Oxidation Catalyst

---- El Tl

0.9 ---- El T3

0.8 > u C 0.7 QJ :::s

------------------------ El T4

---- El TS

--E2 Tl tT 0.6 QJ --E2 T2 '-u.

0.5 QJ .> ..., 0.4 ('Q -:::s

--E2 T3

--E2 T4

- E2 TS

E 0.3 :::s

- E3 Tl

u 0.2 --E3 T2

0.1 --E3 T3

- E3 T4 0

0 0.2 0.4 0.6 0.8 - E3_TS

1

Engine Power (Normalized)

7

1

Real-world Duty Cycles

STP, A B 2 · 3

v t + vt + Cv, ·+ mv· a I t t

f scale

8

MOVES Scaled Tractive Power

STPt = scaled tractive power at time t, skW A = rolling resistance coefficient [kW-s/m] B = rotational resistance coefficient [kW-s2/m2] C = aerodynamic drag coefficient [kW-s3/m3] at = vehicle acceleration at time t [m/s2] m = vehicle mass [metric ton] vt = vehicle speed at time t [m/s] fscale = scaling factor, unitless

I I I

36

9

MOVES Operating Modes (OpMode) Sc

aled

Tra

ctiv

e Po

wer

, skW

30

24

18

12

6

0

Speed: [1–25) mph Speed: [25–50) mph Speed ≥ 50 mph <

0

< 0

erat

ing

Coas

ting,

STP

, STP

ng

Dece

lId

ling

Coas

ti

0 1 11 12 13 14 15 16 21 22 23 24 25 27 28 29 30 33 35 37 38 39 40 MOVES Operating Mode

"'C =-0 ro

i;§ OJ!! C u ·- > +,I u c'+-cu 0 0. 0

V) ·-cu +,I

E~ ·- -~

0.50

0.40

0.30

0.20

0.10

0 .00

0 1 :11 12 13 14 15 16 :21 22 23 24 25 27 28 29 30:33 35 37 38 39 40

MOVES Operating Mode

10

Variability in OpMode Time Distribution: Line-haul

"'C =-0 ro

i;§ OJ!! C u ·- > +,I u c'+-cu 0 0. 0

V) ·-cu +,I

E~ ·- -~

0.50

0.40

0.30

0.20

0.10

0 .00

0 1 11 12 13 14 15 16 21 22 23 24 25 27 28 29 30 33 35 37 38 39 40

MOVES Operating Mode

11

Variability in OpMode Time Distribution: Delivery

12

Variability in OpMode NOx Emission Rates

■

0.00

0.04

0.08

0.12

0.16

NO

x (g

/s)

Combination Long Haul Truck

0 1 11 12 13 14 15 16 21 22 23 24 25 27 28 29 30 33 35 37 38 39 40 MOVES Operating Mode

0.90

- 0.80 Cl) "'C 0 0.70 ~

0.60 C. 0 '-Cl)

0.50 C. 0.40 -0 ·- 0.30 ...., ('0

0:::: 0.20

0.10

0.00

0 1

■ T < 250 degC ■ T ~ 250 degC

l I I I

1112 13 14 15 16 21 22 23 24 25 27 28 29 30 :33 35 37 38 39 40

MOVES Operating Modes

13

1.00

OpMode Time Ratio:Trucks without SCR

T < 250 degC ■ T ~ 250 degC

1.00

0.90

- 0.80 GJ "'C 0 0.70 ~

0.60 C. 0 ~

GJ 0.50

C. 0.40 -0 ·- 0.30 .... ra a:: 0.20

0.10

0.00

0 1 1112 13 14 15 16 21 22 23 24 25 27 28 29 30 33 35 37 38 39 40


14

OpMode Time Ratio:Trucks with SCR

.2

0.15

-~ bO - 0.1 >< 0 z

0.05

■ T < 250 degC

■ T ~ 250 degC

ii I I I 0 1 11 12 13 14 15 16 21 22 23 24 25 27 28 29 30 33 35 37 38 39 40


15

0

Exhaust Temperature Effect:Trucks without SCR

■ T < 250 degC

■ T ~ 250 degC 0.15

-V, ....... bD 0.1 ->< 0 z

0.05

0 i .

0 1 11 12 13 14 15 16 21 22 23 24 25 27 28 29 30 33 35 37 38 39 40


16

0.2

Exhaust Temperature Effect:Trucks with SCR

17

Cycle Total Contribution:Trucks with SCR

Contribution (Ratio) Time NOx

T < 250 degC 0.49 0.65 T ≥ 250 degC 0.51 0.35

18

Conclusions

• MOVES OpModes continue to represent intra-cycle variability

• For trucks with SCR, exhaust temperatureaffects NOx emission rates across all OpModes

• Representativeness of duty cycles could be evaluated based on engine power demand and after-treatment temperature distribution

19

Future Work

• Increase vehicle sample size from HDIUT data • Seek data from other studies. Volunteers? • Analyze temperature cut-off sensitivity • Conduct modal analysis for effect of vehicle

state in previous seconds on NOx emissions in current second

20

Acknowledgements

• US EPA OTAQ – David Choi, Justin Greuel, Prashanth Gururaja,

Chris Laroo, Ed Nam, Larry Oeler, and JamesSanchez

21

Contact Info

[email protected]

[email protected]

[email protected]

mailto:[email protected]



22

Extra Slides

0 -M ..c "-.. a.u E~ -"'C ~ QJ +,J QJ C a. QJ

V') E +,J

QJ cu u ~

..c t: QJ QJ

>~ <(

80

70

60

50

40

30

20 ........................... .

10

0

25400

.. ·· ..

25600

- Veh Spd (mph)

......... AT Temp (degC/ 10}

- NOx (g/ s)

0 .25

0.2

0.15

0.1

. ....... ····································································· .--·

25800 26000

Timestamp

26200

0 .05

0

26400

-V')

"-.. tlO -QJ +,J

cu 0:::: C 0 V') V')

E UJ

X 0 z

23

Aftertreatment Temperature Real-world Example

effect of driving conditions on nox emissions from 2010 ......regulatory class data source myg . hhd...

Documents