lambda 1 high load operation via water injection
TRANSCRIPT
Engine Expo 2016 – Messe Stuttgart, Germany – May 31st to June 2nd 2016
Lambda 1 High Load
Operation via Water
Injection
Sam BarrosDirector of Research and Development
Nostrum Energy, LLC
1
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
Engine Expo 2016 – Messe Stuttgart, Germany – May 31st to June 2nd 2016 3
Motivation
• Avoiding this!
• Enabling the next generation of high efficiency engines
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
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
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
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 ReservoirHigh
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
DirectInjection
Controller
EngineDirect
Injectors
Engine Expo 2016 – Messe Stuttgart, Germany – May 31st to June 2nd 2016 8
Experimental Tests To Be Discussed
Test
NumberFuel
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 None10° CA50 or
KLSA*Production Production Production
Test 3 87 AKI Port Injection10° CA50 or
KLSA*Production Production 1.0
Engine Expo 2016 – Messe Stuttgart, Germany – May 31st to June 2nd 20169
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 PhasingBaseline Engine
Engine Speed (RPM)Engine Speed (RPM)
CA
50
(°A
TDC
)
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 DurationBaseline Engine
Engine Speed (RPM)Engine Speed (RPM)
BD
10
-90
MBT
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 PressureBaseline Engine
Engine Speed (RPM)
NET
MEP
(b
ar)
Engine Expo 2016 – Messe Stuttgart, Germany – May 31st to June 2nd 201611
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 EfficiencyBaseline Engine
Engine Speed (RPM)
NET
Th
erm
al E
ffic
ien
cy (
%)
Engine Expo 2016 – Messe Stuttgart, Germany – May 31st to June 2nd 201612
Experimental Results: Exhaust Gas Temperatures
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
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
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)
Pre
ssu
reR
atio
(:)
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)
Engine Expo 2016 – Messe Stuttgart, Germany – May 31st to June 2nd 201616
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)
Un
bu
rne
dG
as T
em
pe
ratu
re(K
)
Impact of Compression Ratio on Unburned Gas Temperature (3000 RPM, 50 bar BMEP)
A/F = 12.0CA50 = 10° ATDC
Simulation Results
Engine Expo 2016 – Messe Stuttgart, Germany – May 31st to June 2nd 20165/26/2016 17
• Patented jet-to-jet
collision breakup
mechanism
• Reduced spray
penetration and
improved liquid
atomization allow
faster water
vaporization rates
Water Injectors
Engine Expo 2016 – Messe Stuttgart, Germany – May 31st to June 2nd 20165/26/2016 18
• Spray Targeted Nostrum
KiWi; Kinetic Water Injector
• Nostrum Water DI injector
(next phase)
Water Injectors used on this project
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
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
Engine Expo 2016 – Messe Stuttgart, Germany – May 31st to June 2nd 2016
PFI Spray Targeting – Directional Spray Movie
21
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
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
• 5.1% @ 3000 RPM
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)
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
• 19% increase in pump bore
Engine Expo 2016 – Messe Stuttgart, Germany – May 31st to June 2nd 2016
Q&A
26
Sam BarrosDirector of Research and Development
Nostrum Energy, LLC
www.nostrumenergy.com
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