Engine System Technologies for Reducing GHG and NOx
ERC SymposiumUniversity of Wisconsin
Michael Ruth for Gary SalemmeDirector
Advanced Engineering Systems Integration
June 3, 2015
Topics
Potential Future GHG Reductions
What About Lower NOx?
Summary of Future Technology Challenges
2
SuperTruck Technology Contributions
3
Technologies for 50% Engine Thermal Efficiency
4
Combustion & Air Handling Piston bowl size and shape
Injector specification
Calibration optimization
Turbocharger efficiency
Aftertreatment optimization
Parasitic reductions Shaft seal
Variable flow lube pump and viscosity
Geartrain
Cylinder kit friction
Cooling and fuel pump power
WHR system EGR, exhaust, recuperator
Turbine expander
Low GWP refrigerant
SuperTruck Efficiency Improvement Results
Acc
M/G
Air Handling & EGR
Aftertreatment (AT)
Electronic Controls
EnergyRecovery
TransmissionIntegration
Combustion &Fuel Systems
System Optimization
5
Subsystem Technology Palette
2020 – 2030 CO2 Reduction Potential
6
Potential % Improvement vs. 2017 Standards
(On the Certification Cycle)
Medium Heavy-
Duty VocationalKey Technologies
Engine 5 - 11
Advanced Combustion Strategies
Turbocharger and EGR Air Handling
Friction and Parasitic Reductions
Increased Peak Cylinder Pressure
Heat Transfer Management
High Efficiency Aftertreatment
Variable Valve Actuation
Transmission
Integration*3 – 15
Shift Optimization
Cycle Efficiency Management
Hybrid
* Not realized on the engine certification cycle
2020 – 2030 CO2 Reduction Potential
7
Potential % Improvement vs. 2017 Standards
(On the Certification Cycle)
Heavy Heavy-
Duty TractorKey Technologies
Engine 9 - 15
Advanced Combustion Strategies
Turbocharger and EGR Air Handling
Friction and Parasitic Reductions
Increased Peak Cylinder Pressure
High Efficiency Aftertreatment
Heat Transfer Management
Downspeeding
Waste Heat Recovery (WHR)
Engine and
Powertrain
Integration*
3 - 5
Shift Optimization
Cycle Efficiency Management
Hybrid
* Not realized on the engine certification cycle
Engine Power
Waste HeatExhaust to Air
Pump
ExpanderAdditional
Power
Exhaust to Air
BoilerTakes in heat
CondenserReleases Unusable Heat
8
Waste Heat Recovery Technology
Beyond SuperTruck
4th generation design
Improvements for
packaging, cost,
reliability
End-user testing
planned for late 2015
Production possible
by ~2020
4-5% Fuel Consumption Benefit
In Cylinder Heat Transfer Management
9
Piston A:
Max Temp = 345 C
Piston B:
Max Temp = 386 C
Base Piston:
Max Temp = 254 C
0.6 pt heat loss reduction
0.3 pt GITE improvement
0.3 pt heat loss reduction
0.1 pt GITE improvement
BTE impact: + 0.8% BTE
Koeberlein 2014 AMR
Engine Connection to Other Technologies
10
Transmission
Integration
Hybrid and
Stop-Start
Vehicle
Integration
Connectivity and
Telematics
Long Term Approach to Electrification
Lower Operating Cost
Inc
rea
se
d F
un
cti
on
ali
ty
Range
Extended
EV
Battery
EV
PlugIn
HybridHigh
Voltage
HybridLow
Voltage
HybridElectric
Accys
Start
Stop
Lower Initial Cost
12
What impact will lower NOx standards
have on GHG and fuel consumption?
0 200 400 600 800 1000 12000
0.1
0.2
0.3
0.4
0.5
Time (sec)
FT
IR T
P N
Ox (
g)
Gator Dragster Cold FTP 12-02-2013
0 200 400 600 800 1000 12000
5
10
X: 333
Y: 7.039
Time (sec)
Cum
ula
tive N
Ox (
g)
Diesel Low NOx Challenge
13
At 0.2 g/hp*hr 80% of composite
tailpipe NOx is created during warmup of the SCR system
Managing NOx during catalyst warm-up is key.
0 1 2 3 4 5 680
85
90
95
100
Engine Out NOx (g/hp*hr)
Afte
rtre
atm
en
t N
Ox C
on
v. E
ff (
%)
0.02 g/hp*hr
0.05
0.1
0.2
System Performance Requirements
14
Tailpipe Out Targets
Engine
Opportunities
Aftertreatment
Opportunities
Combined System
Performance
ATP-LD Tier 2 Bin 2 Diesel Technologies
15
Q
Q
Engine
2 Loop EGR
SCRF
PNA
Direct NH3
Injection
Close Coupled
Catalysts
Low Thermal
Inertia
Exhaust
Advanced
Controls
More EGR Path to Lower Engine Out NOx
16 Engine Out NOx
EG
R F
low
Durability Concerns
Increased Heat Rejection
Increased Pumping Losses
Increased PM and DPF Regen
Higher PCP and Friction
Challenges Opportunities
Advanced EGR
High Effy Turbo
Improved Inj & Combustion System
Stop - Start
Improved Design for Low Friction
WHR potential
Catalyst Warmup Considerations
17Catalyst Warm Up Time
Aft
ert
rea
tme
nt N
Ox
Co
nve
rsio
n
Increased Thermal
Management Fuel
Challenges Opportunities
Urea Deposits
Poor Low Temp
NOx Conversion
More Efficient Thermal
Management & conservation
NOx Storage and Low
Temp Catalysts
Advanced Controls
GHG Penalty at Low Tailpipe NOx
18
Improving Current Conventional
Diesel Combustion w/SCR
• More work needed to identify a robust 0.02 g/hp*hr diesel solution
• Potential path to ~0.1 g/hp*hr with minimal CO2 penalty
• New technology will help, but needs development
New Diesel Technologies
• BTE Improvements
• Catalysts (SCRF, NOx
Storage)
• Urea Dosing Controls
and Strategies
• Thermal Management
Diesel
GHG Penalty at Low Tailpipe NOx
19* Includes methane emissions as equivalent CO2
Improved Current Technology
Stoichiometric EGR w/TWC
Natural Gas*
New Diesel Technologies
Improving Current Conventional
Diesel Combustion w/SCR
New Nat Gas Technologies
• BTE Improvements
• Close Coupled AT
• TWC and Air Handling
Controls
• More EGR
• Advanced TWC
Diesel • Path to 0.02 g/hp*hr with natural gas with small CO2 penalty
Alternative Fuels Compression Ignition
20
Combustion Noise
Low Exhaust Temperatures
Controllability
HC Emissions
High PCP
Challenges Opportunities
Low Temp Aftertreatment
Closed Loop Model Based
Combustion Controls
Design for Knock
Knock Control
Koeberlein: 2014 DOE AMR
Reduced NOx and PM Aftertreatment
Power Density
Cold Start NOx
Engine Out BSNOx [g/hp*hr]
GHG Penalty at Low Tailpipe NOx
21* Includes methane emissions as equivalent CO2
Improved Current Technology
Stoichiometric EGR w/TWC
Natural Gas*
Diesel
New Diesel Technologies
Improving Current Conventional
Diesel Combustion w/SCR
New Nat Gas TechnologiesAdvanced
Combustion
Advanced
Combustion
• Path to 0.02 g/hp*hr with advanced combustion with good CO2
• Still in research
Ultra Low Carbon Powertrain - ETHOS
Divided
Exhaust
Manifold
Advanced
Controls
TWC
AftertreatmentVariable
Valvetrain Direct Injection
Fuel System
Optimized
Charge Motion
High
Compression
Ratio
Increased
Peak
Cylinder
Pressure
Combustion
Optimization
Aluminum
Cylinder Head
Compressor
Bypass
Stop / Start
22
Well–To–Wheels Carbon Emissions
35%-80% CO2 Reduction Potential
-100.0-95.0-90.0-85.0-80.0-75.0-70.0-65.0-60.0-55.0-50.0-45.0-40.0-35.0-30.0-25.0-20.0-15.0-10.0
-5.00.0
FTP HFET HTUF P&DCummins
P&D
%C
han
ge in
CO
2
CO2 Emissions Reduction With 17.5k GVWFarmed Trees Ethanol Pathway
Diesel Gasoline
Fuel
Elemental
Carbon
Well to Tank
Carbon
g CO2/ MJ g CO2/ MJ
California Reformulated Gasoline 72.90 98.95
California Ultra-Low Sulfur Diesel 74.10 98.03
Corn Ethanol 71.02 65.66
Cellulosic Ethanol from Farmed Trees 71.02 21.40
California E85 - Corn 71.34 70.65
California E85 - Farmed Trees 71.34 33.03
23
Program Target
Summary
Engine system technology can provide significant improvement in fuel
consumption and CO2 emissions and continue to reduce NOx
emissions
Key Areas for Research Include:
24
Knock Control in High
BMEP Premixed Engines
Combustion Design for Very High Dilution
Compression and Spark Ignited Engines
System Integration of PNA Catalysts
Fuel Efficient, Fast Catalyst Warmup
Low Temperature
Aftertreatment Performance
Measurement Systems for:
In Cylinder Heat Transfer
Fired Engine Friction
Hybrid System Component Cost:
Batteries, Power Electronics