Efficiency and Emission Improvements for Future Off-road ... · Efficiency and Emission Improvements for Future Off-road Engines ... Fendt 828 Vario. 248. 14. 262. 486. 19. 505. ...

Efficiency and Emission Improvements for Future

Off-road Engines

Rich WinsorBryan GeisickDanan Dou

June 3, 2015

Agenda

• Introduction to Off-road Engines

• Customer Needs

• Emission Control

• Fuel efficiency, power growth, and heat rejection

2

Extreme Operating Conditions for Off-Road

3

Wet Cold & Hot Dusty Off-Level

High Altitude - Mining at 14,000 ftRemote worksitesSeasonal use

John Deere Diesel Engine Applications

4

MachineApplications

Agriculture Construction& Forestry

External OEMs

4.5L 6.8L

9L 13.5L

5

7310R Record Previous RecordholdersTest Condition kg/kWh kg/kWh

75% Max pull, full throttle 0.255 John Deere 720 0.258 *

50% Max pull, full throttle 0.282 Deere 7810 IVT 0.284

* 58 year old Record

Drawbar Results @ Nebraska Tractor Test Lab

6

DLG Official Test Results - Stage IV

PowerMix TransportDiesel DEF Total Diesel DEF Total

Fendt 828 Vario 248 14 262 486 19 505JD 7310R e23 248 9 257 450 12 462

800 1000 1200 1400 1600 1800 2000 2200

Torq

ue

Engine Speed (rpm)

13.5L Tractor13L Truck

Off-Road Engines Operate Differently

7

Tractor Engine: extended time at high speed and loadOptimize for productivity and fuel efficiency

Truck

800 1000 1200 1400 1600 1800 2000 2200

Torq

ue

Engine Speed (rpm)

Row Crop Tractor

Combine

Applications Require Different Torque Curves

Tractors: High torque at low speed for vehicle launchingHigh torque rise for difficult conditions

Combines: Maximum power

8

Tractors etc. HarvestersConstruction & Forestry

Power (kW)

Wide Power Range and High Configuration Variance

9

Volume

Power (kW)

Trade-off Summary of Low vs. High Power

10

Low kW/L vs High kW/L

Power

Torque

BSFC

$ /kW

EmissionCold Start

Durability

Altitude

Transient

Multiple FT4 Configurations(Three 4045 engines shown)

Five engine platforms (3029, 4045, 6068 , 6090, 6135)Twenty performance hardware sets (turbos, injectors,

pistons, cylinder heads, exhaust manifolds, etc.)~55 base calibrations with multiple torque curves on most

11

100%

300%

500%

700%

900%

1100%

1300%

1500%

1700%

1900%

Stage I Stage II Stage IIIA Stage IIIB Stage IV

# of

Fun

ctio

ns&

DTC

Electronics and Intelligent Software Provide Flexibility in System Integration

12

48 pinIn-line fuel pump

Fuel SystemAir SystemEmission SystemDiagnosticsTelematics…

162 Pin

13

0

200

400

600

800

1000

1200

1400

1600

1800

600 800 1000 1200 1400 1600 1800 2000 2200 240015%

10%

15%

15%

15%

10%

10%

10%

Engine Speed (rpm)

Torq

ue (N

m)

NRTC

8 Mode

Non-Road Emission Test Cycles:8 Mode (>T1), NTE (>T3), Transient Cycle (>IT4)

Bubble size & value: weighing factor

Deere Final Tier 4 System ArchitectureFT4 Standard: PM=0.02g/kWh, NOx=0.4g/kWh

14

Emission System

DOC-DPF for PMEGR and SCR for NOxDEF storage and deliverySensors & control System

Value Proposition

High performanceLow fluid consumption

0

0.1

0.2

0.3

0.4

63 129 92 224 168 317 241 460

Tailp

ipe

NO

x (g

/kW

h)

Power (kW)

FT4 Fulfilled for Wide Power Range

Emission Standard

13.5L9L6.8L4.5L

Min Power, Max Power

15

Low Power Output Produces Low Temperature (More Challenging for SCR Performance)

High Power Rating

Low Power Rating

Cold NRTC Hot NRTC20min Soak

16

NRTC=Non Road Transient Test Cycle

High Power Rating

Low Power Rating

↓Poor SCR Activity ↓Poor SCR Activity

Realize CO2 Reduction from Combustion, Air System and Mechanical Design

17

Indicated Power

Brake Power

Friction* & Auxiliary

Pumping Loss

WasteEnergy

ExhaustEnergy

Water Cooling

Charge Air Cooling

ATRestriction

ATCooling

SCR Warmup

DPF Regen

Primary Secondary

-3%

-2%

-1%

0%

1%

2%

3%

1 2 3 4 5 6 7

Flui

d C

ost C

hang

e

Engine Out NOx (g/kWh)

Fluid Consumption Optimum Vs. Fuel/DEF Cost Ratio (EGR Engine Scenario)

18

Fuel/DEF Cost = 1

Fuel/DEF Cost = 2

Fuel/DEF Cost = 3

OptimumRange

~92% NOx Eff

Minimizing Total Fluid Cost

• Modern EGR engine offers superior BSFC

• Engine out NOx level: 2.5 - 5 g/kWh

• High NH3 uniformity for SCR reactions

• Model based controls and calibration optimization

• Ensure NH3 availability for emission compliance

• Limit NH3 storage to avoid NH3 thermal release

• EGR and SCR optimization: emission and performance

19

What’s Next: Power and Efficiency

Higher Fuel EfficiencyLower Specific Heat RejectionPower GrowthHigher NOx/PM RatioNext Gen ECUImproved Diagnostics (DEF Quality Sensor)

Particle Number ComplianceDown SizeLower CostIntegrated PackagingLower RestrictionInnovative CatalysisReduced Active Regeneration

Integrated System Solution

+

20

Heat Rejection is Important in Off-highway Applications

• Dirty environment without ram air results in cooling difficulty

• Debris can interfere with cooling

• Lower fan power improves vehicle fuel economy

• Higher specific output reduces specific heat rejection

21

Fuel Economy

22

Combustion now focuses on efficiency, power and heat rejection rather than emission characteristics.

23

Capability of Exhaust Aftertreatment Broadens Design Space

24

Combustion System Development Process

Swirl Testing

Combustion

Simulation

Test

Design

Port design

Combustion CFD

Air motion CFD

Fuel Sprays

25

Analysis-Based Design Effort:Initial CFD Correlation with Test Results

ISSUES:Boundary Conditions – pressure,

temperature, EGRSurface TemperaturesCombustion ModelGrid resolution

Rate of Injection (ROI)Soot Model

Improved CFD Results on Same Hardware Sets

Model improvements significantly improved the correlations, but it appears further effort on fuel sprays is needed.

26

Diesel Combustion System Design

• Designed for highest loads; lighter loads allow more flexibility in injection process

• Diesel fuel will burn with 99+% efficiency unless situation is unusual – misfire or excessively rich

• Diesel combustion is generally mixing controlled, not kinetically controlled, after ignition

• When the heat is released is important – start slowly and finish at high rate for efficiency without excessive cylinder pressure

• Timing and quantity of in-cylinder heat loss is important

• With DPF and SCR, PM and NOx emissions have less importance

27

EGR is not just for Emission Control

• EGR reduces temperatures of piston, cylinder head, exhaust manifold, turbocharger, exhaust throttle and aftertreatment, although system heat rejection is increased

• With an optimized air system, fuel economy with EGR is at least as good as without EGR

• EGR reduces DEF consumption by the SCR system

• EGR is no longer a limiting factor for low engine-out PM due to newer combustion systems

28

Combustion System Issues

• Compression ratio (expansion ratio)• Heat loss – wasting energy• Time loss – not burning at optimum

time• Engine speed – more time at low

speed• Smoke and PM do not indicate poorer

combustion in a general sense –heating value of smoke is negligible

• Higher NOx tends to indicate faster combustion

• High swirl systems may give fast combustion and low smoke, but heat loss can be high

• Quiescent combustion systems can give higher efficiency, although PM may be slightly higher

29

Combustion System Generalizations

Parameter Legacy Split-Spray Low TurbulencePM base lower higherNOx base higher higher

Rated BSFC base same lowerPart Load BSFC base lower same

Head Temp. base lower lowerPiston Temp. base higher lower

Heat Rejection base same lowerOil Sooting base better worseApplication FT4 No DPF High Power

30

10

15

20

25

30

35

1970 1980 1990 2000 2010 2020

Pow

er D

ensi

ty (

kW/L

)

Year

Continuous Demand for Power GrowthExample: Tractor Power Increase Over Time

31

Approach for Power Growth

• Injection system – larger pump, if necessary• Air system – staged turbocharging• Reduce torque rise, if possible• Strengthen parts as necessary to tolerate higher

cylinder pressure• Design combustion systems with lower thermal

loading on combustion chamber• Improve head, piston and liner cooling• Possible turbocompounding

32

Electric Turbocompounding

Increased powerReduced fuel consumptionFlexible installation of unitRequires vehicle to use

electrical power, esp. at high loads

33

Committed to Those Linked to the Land

Thank You for Your Attention