Development and Demonstration

of a Fuel-Efficient HD Engine

(Dept of Energy Supertruck Program)

Acknowledgements: DOE Contract: DE-EE0003303

Industrial Partners: Bosch, ARGONNE, Federal Mogul, WERC

William de Ojeda

Navistar 

Technical Session: High-Efficiency Engine Technologies Part 1 

DOE DEER CONFERENCE

16 October 2012

Dearborn, Michigan

1
Project Goals: 

Approach for Fuel Economy

2

Baseline

2010 ProStar with 

MAXXFORCE 13L

Demonstrate 50% improvement in overall freight efficiency of a tractor-trailer

• 30% through tractor/trailer technologies

• 20% through engine technologies

0

10

20

30

40

50

60

70

80

90

Aerodynamic

losses

Rolling

resistance

Auxiliary

loads

Drivetrain

losses

kW

Energy Audit 

on Baseline and Target Supertruck

Base

Target

160kW

112 kW
Engine Technologies

3

2. Air System

1. Combustion

3. Friction

Accessories

4. WHR

20% 

Base 

efficiency

BTE > 50%

turbocompounding

Leverage 

Technologies

Electrical Turbocompounding

Rankine Cycle

Low Friction components

Lube system

Cooling system

VVA + turbo match

VVA 

Turbo optimization

2900bar capability

Comb match

Increased PCP

Optimum timing

Higher Injection Pressure

Aftertreatment

Evaluation at Fully 

Loaded Drive Cycle

(65,000 lb vehicle weight)
Increased PCP

Optimum timing

Higher Injection Pressure

Aftertreatment

Optimization criteria

4

Leverage 

Technologies

Optimize 

Integration Criteria

Efficiency gain

Weight

(Ton-mile/gallon)

Cost 

(payback)

2. Air System

1. Combustion

3. Friction

Accessories

4. WHR

20% 

Base 

efficiency

BTE > 50%

Electrical Turbocompounding

Rankine Cycle

Low Friction components

Lube system

Cooling system

VVA 

Turbo optimization

Evaluation at Fully 

Loaded Drive Cycle

(65,000 lb vehicle weight)
Engine Targets

5

Leverage 

Technologies

Evaluation at Fully 

Loaded Drive Cycle

(65,000 lb vehicle weight)

2. Air System

1. Combustion

3. Friction

Accessories

4. WHR

20% 

Base 

efficiency

BTE > 50%

Electrical Turbocompounding

Rankine Cycle

Low Friction components

Lube system

Cooling system

VVA 

Turbo optimization

Increased PCP

Optimum timing

Higher Injection Pressure

Aftertreatment

Target :

20% Efficiency gain

20% Ton-mi/gal 
Development Facilities

6

BOSCH High-injection pressure capability

High Compression ratio

CFD-Engine correlations

Navistar Combustion Development

Air / cooling system 

Emissions 

Turbocompounding

EGR-Rankine Cycle

Argonne 

National Labs

WERC

Fuel Reactivity

Cylinder head redesign

PFI system installation

Simulations

Ref DEER 2012 Navistar – Dr. Yu Zhang

Federal Mogul Friction Benchmark

Power cylinder components
Efficiency Roadmap

Technology Introduction

7

phase 1: cooling sys

TUCO (Next Generation)

phase 2: lube sys

friction phase 3: power cyl

Progress to date

47.3% BTE

Current Activities

ORC system will be used 

only on dyno

 Preparing engine for vehicle to run at ~50% BTE

Re-optimized comb High-CR

VVA

TUCO

Comb
38

40

42

44

46

48

50

0.0 0.5 1.0 1.5

BTE

NOx (g/bhp-hr)

N=1200rpm

BMEP=17bar

Combustion

Optimization of hardware and emissions

8

Baseline

In Cylinder Solution

Combustion match

Two stage boost

Two stage cooling

High Injection Pressure

NOx ~ 0.2-0.5gNOx

Supertruck Oct 2011

Higher CR

Advanced Fuel System

NOx ~1gNOx

Projected development on 

Supertruck during 2013

Current Demo Oct 2012 

Supertruck Program

Friction reduction + TUCO
Electrical Turbocompounding

System optimization

9

Advantages

 Highest efficiency opportunity

 Synergistic with Supertruck hybridization

Challenges:

 Must reduce engine back pressure

 Must keep temps and flows up

turbo-generator

ECU

Lube oil

Power electronics

Brake resistor

Hybrid Bus 700 VDC BUS

PTC

High efficiency 

turbochargers

Aftertreatment 

location

Controls

0

2

4

6

8

0.0 0.2 0.4 0.6 0.8 1.0

Fuel Improvement (%)

NOx (g/bhp-hr)

260kW

140 kW

Decrease restriction
Turbocompounding

Installation on base engine

10

Turbo

generator

Bypass

DPF

Lube system

Power electronics

Pump

tank

cooler

filter

ProStar Vehicle Installation
Improved Base Engine

BTE gains across the engine map

11

Phase 3

 Power cyl comp

Phase 2

 Cooling

Lube oil

0.75 +1 %

+2%

+3%

Phase I 

 Cooling system

+1 %

+2%

0.45
Re-matching the combustion 

12

With turbocompounding

 Potential gains with higher 

compression ratio

 Re-examine other boundaries:

Air System

Peak cylinder pressures

Optimum EGR rates

 ...

39%

40%

41%

42%

43%

44%

0.0 0.5 1.0 1.5 2.0

BTE (%)

BSNOx (g/bhp-hr)

CR

ΔSOI= 3o

ΔSOI= 3o

1500 rpm

CR gains are substantial at CR higher engine speeds

42.5

43.0

43.5

44.0

44.5

45.0

45.5

low baseline high

BTE

1200 rpm 1500 rpm

38.0

39.0

40.0

41.0

42.0

43.0

44.0

low baseline high

BTE

Gain ~ +2 %

Air system 

limitations
Advanced BTE Concept

Impact of Fuel Reactivity

13

 Significant improvement on BTE with fuel reactivity

 At better controlled engine out emissions

Ref DEER 2012

Navistar – Dr. Yu Zhang

Progress to Date

Diesel

45%

at ~1gNOx

BTE gain

Alcohol Fuels

45.1%

NOx ~ 0.1gNOx 

Gasoline/Diesel

43.6%

NOx ~ 0.1gNOx 

43.6%

45.1%

Current Target

Increased reactivity

BTE > 47%

at NOx < 0.1gNOx 

47%

Friction

TUCO

VVA+CR

ORC

Technologies

from the Diesel 

platform
Summary

Project is assessing and developing engine and vehicle technologies to:

 Improve freight efficiency for class 8 truck and trailer 

 Attain peak engine efficiencies of 50% BTE

The work to date includes:

 Combustion optimization demonstrated efficiency improvement to 45% BTE

 Turbocompounding improvement increased BTE to 46.5%

 First phases of Base Engine Technologies increased BTE further to 47.2%

In addition:

 Engine has been prepared to examine the impact of Fuel Reactivity

Current fuel studied increased the engine efficiency above 45% while keeping engine NOx and 

PM levels significantly lower than the Diesel counterpart.

14
Acknowledgements 

Engine Project Partners

TM

CFD Fuels Enabling 

Technologies

15

WERC ARGONNE BOSCH

NATIONAL

LABS

FEDERAL

MOGUL

Willy de Ojeda

Navistar, Inc.

2601 Navistar Drive

Lisle, IL 60532

willy.deojeda@navistar.com

Thank You