Enabling the next generation of High Efficiency Engines. Despite increasing popularity, engine “downsizing” does not delivery dramatic real-world fuel economy benefits. Downsized engines must be operated at higher loads, often into regions where spark retard and/or over fueling is used to control knock. Maximum engine output in SI engines is limited by knock (auto-ignition). Therefore, mitigation of knock is an enabler for aggressive downsizing AND increased performance.

1. Engine Expo 2016 – Messe Stuttgart, Germany – May 31st to June 2nd 2016
Lambda 1 High Load
Operation via Water
Injection
Sam Barros
Director of Research and Development
Nostrum Energy, LLC
1

2. Engine Expo 2016 – Messe Stuttgart, Germany – May 31st to June 2nd 2016
• Motivation
• Experimental Setup
⁃Engine Setup
⁃Water Injection
⁃Controls
• Simulation
• Experimental Results
• Conclusions
• Next Steps
2
Outline

3. Engine Expo 2016 – Messe Stuttgart, Germany – May 31st to June 2nd 2016 3
Motivation
• Avoiding this!
• Enabling the
next generation
of high
efficiency
engines

4. Engine Expo 2016 – Messe Stuttgart, Germany – May 31st to June 2nd 2016
• Despite increasing popularity, engine “downsizing” does
not delivery dramatic real-world fuel economy benefits.
• Downsized engines must be operated at higher loads,
often into regions where spark retard and/or over fueling is
used to control knock.
• Maximum engine output in SI engines is limited by knock
(auto-ignition)
• Mitigation of knock is an enabler for aggressive downsizing
AND increased performance
4
Motivation

5. Engine Expo 2016 – Messe Stuttgart, Germany – May 31st to June 2nd 2016 5
Experimental Setup
Baseline Engine
• SIDI 2.0L GM Ecotec LTG
• Twin Scroll Turbocharger
• Dual Independent Cam Phasing
• Large Aftermarket Support

6. Engine Expo 2016 – Messe Stuttgart, Germany – May 31st to June 2nd 2016
• Injectors installed in intake
manifold
• Direct Injection also an option
6
Experimental Setup – Water Injection
Water
Rail
Injector with Bosses
welded to manifold

7. Engine Expo 2016 – Messe Stuttgart, Germany – May 31st to June 2nd 2016
• Test water is generated
through Reverse
Osmosis
• High Pressure supply
(250 bar) for Direct
Injection testing
• Low Pressure supply (10
bar) for Port Injection
testing
• Flow measured with
Coriolis meter
7
Experimental Setup – Water Injection
Building
Water
Supply
RO Water Reservoir
High
Pressure
Pump
Flow
Metering
Device
Air
Supply
~110psi
12V
Signal
I/O
Drain to
Sewer
System
Reverse
Osmosis
Filtration
System
Filter
PWI
Water
Tank
Vent to
Atmosphere
Temperature
and Pressure
Transducers
Port
Injectors
Data
Acquisition
System
Intake
Manifold
Exhaust
System
Engine
Temperature
and Pressure
Transducers
Port
Injection
Controller
Exhaust
System
Air
Supply
~200psi
Direct
Injection
Controller
Engine
Direct
Injectors

8. Engine Expo 2016 – Messe Stuttgart, Germany – May 31st to June 2nd 2016 8
Experimental Tests To Be Discussed
Test
Number
Fuel
Water
Injection
Spark Timing /
Combustion
Phasing
I-Cam E-Cam Lambda
Test 1
91 AKI
(Engine
manufacturer req.)
None Production Production Production Production
Test 2 110 AKI None
10° CA50 or
KLSA*
Production Production Production
Test 3 87 AKI Port Injection
10° CA50 or
KLSA*
Production Production 1.0

9. Engine Expo 2016 – Messe Stuttgart, Germany – May 31st to June 2nd 2016
9
Experimental Results: Combustion
0
5
10
15
20
25
30
1500 2000 2500 3000 3500 4000 4500 5000 5500
CA50 EA; 91 AKI, Baseline
CA50 EA; 110 AKI, MBT / KLSA
CA50 EA; 87 AKI, MBT / KLSA, Lambda 1
Combustion Phasing
Baseline Engine
Engine Speed (RPM)Engine Speed (RPM)
CA50(°ATDC)
0
5
10
15
20
25
30
35
40
45
1500 2000 2500 3000 3500 4000 4500 5000 5500
BD10-90_EA; 91 AKI, Baseline
BD10-90_EA; 110 AKI, MBT / KLSA
BD10-90_EA; 87 AKI, MBT / KLSA, Lambda 1
Burn Duration
Baseline Engine
Engine Speed (RPM)Engine Speed (RPM)
BD10-90
MBT

10. Engine Expo 2016 – Messe Stuttgart, Germany – May 31st to June 2nd 2016 10
Experimental Results; Output
0
5
10
15
20
25
30
35
1500 2000 2500 3000 3500 4000 4500 5000 5500
NMEP EA; 91 AKI, Baseline
NMEP EA; 110 AKI, MBT / KLSA
NMEP EA; 87 AKI, MBT / KLSA, Lambda 1
Mean Effective Pressure
Baseline Engine
Engine Speed (RPM)
NETMEP(bar)

11. Engine Expo 2016 – Messe Stuttgart, Germany – May 31st to June 2nd 2016
11
Experimental Results; Efficiency
0
5
10
15
20
25
30
35
40
1500 2000 2500 3000 3500 4000 4500 5000 5500
Net Thermal Efficiency; 91 AKI, Baseline
Net Thermal Efficiency; 110 AKI, MBT / KLSA
Net Thermal Efficiency; 87 AKI, MBT / KLSA, Lambda 1
Net Thermal Efficiency
Baseline Engine
Engine Speed (RPM)
NETThermalEfficiency(%)

12. Engine Expo 2016 – Messe Stuttgart, Germany – May 31st to June 2nd 2016
12
Experimental Results: Exhaust Gas Temperatures

13. Engine Expo 2016 – Messe Stuttgart, Germany – May 31st to June 2nd 2016
Simulation
13
• 1D Engine Simulation was utilized to scope the
High BMEP Build (Target 50 bar BMEP)
⁃ Determination of required air pressure and flow
⁃ Investigation of peak cylinder pressure over a range of
compression ratios
⁃ The same simulation model will be used to evaluate
the impact of water injection

14. Engine Expo 2016 – Messe Stuttgart, Germany – May 31st to June 2nd 2016 14
• Fuel Enrichment and
Combustion Phasing
both have large
impact on Net
Thermal Efficiency
• Good opportunity for
efficiency
improvements
Simulation Results

15. Engine Expo 2016 – Messe Stuttgart, Germany – May 31st to June 2nd 2016
Simulation Results
15
3
3.25
3.5
3.75
4
4.25
4.5
4.75
5
700 750 800 850 900 950
Airflow (kg/hr)
PressureRatio(:)
Airflow and Pressure Requirement Over a Range of Lambda and Compression Ratio
(3000 RPM, 50 bar BMEP)
• Required P/R and mass
flow are challenging for
a single compressor
• Boost pressure is
currently supplied via an
external compressor
• Good candidate for
alternative boosting
systems (multi-stage,
compounded)

16. Engine Expo 2016 – Messe Stuttgart, Germany – May 31st to June 2nd 2016
16
11.0:1 chosen as a compromise between efficiency, peak cylinder pressure, and
unburned gas temperature (knock propensity)
200
300
400
500
600
700
800
900
1000
-75 -55 -35 -15 5 25 45 65 85 105 125
CR = 9.2:1
CR = 10.0:1
CR = 11.0:1
CR = 12.0:1
Auto-Ignition Temperature; Iso-Octane
Theta (Crank Angle)
UnburnedGasTemperature(K)
Impact of Compression Ratio on Unburned Gas Temperature
(3000 RPM, 50 bar BMEP)
A/F = 12.0
CA50 = 10° ATDC
Simulation Results

17. Engine Expo 2016 – Messe Stuttgart, Germany – May 31st to June 2nd 2016
5/26/2016 17
• Patented jet-to-jet
collision breakup
mechanism
• Reduced spray
penetration and
improved liquid
atomization allow
faster water
vaporization rates
Water Injectors

18. Engine Expo 2016 – Messe Stuttgart, Germany – May 31st to June 2nd 2016
5/26/2016 18
• Spray Targeted Nostrum
KiWi; Kinetic Water Injector
• Nostrum Water DI injector
(next phase)
Water Injectors used on this project

19. Engine Expo 2016 – Messe Stuttgart, Germany – May 31st to June 2nd 2016
PFI Spray Targeting – Symmetric Spray
19
Intake port impingement due to
wider, non targeted-symmetric
spray plume

20. Engine Expo 2016 – Messe Stuttgart, Germany – May 31st to June 2nd 2016
PFI Spray Targeting – Directional Spray
20
Intake port impingement avoided
significantly by a narrower,
directional spray plume targeted
to the back of the intake valve

21. Engine Expo 2016 – Messe Stuttgart, Germany – May 31st to June 2nd 2016
PFI Spray Targeting – Directional Spray Movie
21

22. Engine Expo 2016 – Messe Stuttgart, Germany – May 31st to June 2nd 2016
Liner & Piston Impingement
22
Fuel impingement on
the liner due to
improper spray
targeting
Piston Impingement
film

23. Engine Expo 2016 – Messe Stuttgart, Germany – May 31st to June 2nd 2016 23
Conclusions
• Port water injection has been successfully demonstrated
near current production best in class full load levels (~27
bar BMEP)
⁃ Enabled near MBT Combustion Phasing (water flow limited by
instrumentation) on “Regular” 87 AKI Fuel and stoichiometric
operation
⁃ Resulted in a significant increase in Net Thermal Efficiency over
production across all speeds
• 34% @ 3000 RPM
⁃ Resulted in a significant increase in NMEP over production across all
speeds

24. Engine Expo 2016 – Messe Stuttgart, Germany – May 31st to June 2nd 2016
• Evaluate water injection at higher levels of BMEP
• Evaluate water injection at increased compression ratio
• Compare Direct Water Injection to Port Water Injection
• 1D Simulation of Water Injection
• Reduce water usage though spray targeting and reduction in
droplet size
24
Next Steps (Near Term)

25. Engine Expo 2016 – Messe Stuttgart, Germany – May 31st to June 2nd 2016 25
High BMEP Engine Components
• Currently no production engine
at this cylinder pressure
• Production intent
⁃ Forged Pistons & Connecting
Rods
⁃ High Strength head studs
⁃ 10W40 High ZDDP Synthetic
Oil
⁃ Increased valve lift
⁃ Increased valve spring stiffness
⁃ Larger High Pressure Fuel
Pump
• 83% increase in fuel flow

26. Engine Expo 2016 – Messe Stuttgart, Germany – May 31st to June 2nd 2016
Q&A
26
Sam Barros
Director of Research and Development
Nostrum Energy, LLC
info@nostrumenergy.com
www.nostrumenergy.com
For full powerpoint