Development of an SI DI Ethanol Optimized Flex Fuel Engine ... · Project Objective – Minimize...
Transcript of Development of an SI DI Ethanol Optimized Flex Fuel Engine ... · Project Objective – Minimize...
Development of an SI DI Ethanol Optimized Flex Fuel Engine Using Advanced Valvetrain
Wayne Moore, Matt Foster, Kevin Hoyer, Keith ConferDelphi Advanced Powertrain
DEER ConferenceSeptember 29, 2010
29SE2010 2
Introduction
Project Objective– Minimize the fuel economy penalty currently seen when flex
fueled engines are run on high-percentage ethanol blends
Approach– Increased base engine compression ratio– Control of intake valve closing time with 2 step valvetrain
» Compression ratio management » Load control with effective displacement
Presentation Content– Naturally aspirated operation– Benefits of single intake valve deactivation
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Hardware Features
2 Step Valvetrain
LIVC High-lift cam EIVC Low-lift cam
DICP Dual Independent Cam PhasingLIVC Late Intake Valve ClosingEIVC Early Intake Valve ClosingCR Compression RatioWOT Wide Open Throttle
2.0 L DITurbocharged
Engine with DICP
Extended Range IntakeCam Phaser
80° crank Intake authority 50° crank Exhaust authority
Custom Pistons Increased CR from
9.2:1 to 11.85:1
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High Lift
Valvetrain Implementation
Intake Phasing enables effective displacement control
2-Step increases dynamic load range
Low Lift
CAD
Exhaust Intake
TDC Gas Exchange
0 720180 360 5400 Phasing Max Phasing
Intake Cam Phasing (° Cam)
Effe
ctiv
eD
ispl
acem
ent(
L)
-40 -30 -20 -10 00.1
0.15
0.2
0.25
0.3
0.35
0.4
0.45
0.5
0.55
0.6
Low LiftHigh Lift
Valvetrain Effective Displacment ControlE85 Fuel, Unthottled
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Intake Cam Phasing (° Cam)
BM
EP(k
Pa)
-40 -30 -20 -10 0200
400
600
800
1000
1200
1400
Valvetrain Based Load ControlE85 Fuel, Unthrottled
Low LiftHigh Lift
Volume (L)
Pres
sure
(bar
)
0.1 0.2 0.3 0.4 0.5 0.610-1
100
101
102
PV DiagramE85 Fuel, Wide Open Throttle
Volume (L)
Pres
sure
(bar
)
0.1 0.2 0.3 0.4 0.5 0.610-1
100
101
102
PV DiagramE85 Fuel, Wide Open Throttle
Volume (L)
Pres
sure
(bar
)
0.1 0.2 0.3 0.4 0.5 0.610-1
100
101
102
PV DiagramE85 Fuel, Wide Open Throttle
Volume (L)
Pres
sure
(bar
)
0.1 0.2 0.3 0.4 0.5 0.610-1
100
101
102
PV DiagramE85 Fuel, Wide Open Throttle
Volume (L)
Pres
sure
(bar
)
0.1 0.2 0.3 0.4 0.5 0.610-1
100
101
102
PV DiagramE85 Fuel, Wide Open Throttle
Volume (L)
Pres
sure
(bar
)
0.1 0.2 0.3 0.4 0.5 0.610-1
100
101
102
PV DiagramE85 Fuel, Wide Open Throttle
Valvetrain Implementation
Unthrottled low load rangePhase from low/high lift
with torque continuity
CAD0 180 360 540 720
TDC Gas Exchange
Exhaust Intake
CAD0 180 360 540 720
TDC Gas Exchange
Exhaust Intake
CAD0 180 360 540 720
TDC Gas Exchange
Exhaust Intake
CAD0 180 360 540 720
TDC Gas Exchange
Exhaust Intake
CAD0 180 360 540 720
TDC Gas Exchange
Exhaust Intake
CAD0 180 360 540 720
TDC Gas Exchange
Exhaust Intake
CAD0 180 360 540 720
TDC Gas Exchange
Exhaust Intake
Volume (L)
Pres
sure
(bar
)
0.1 0.2 0.3 0.4 0.5 0.610-1
100
101
102
PV DiagramE85 Fuel, Wide Open ThrottlePV Diagram
E85 Fuel, Unthrottled
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SOI (° aTDCf)
BSF
C(g
/kW
hr)
EHC
(ppm
),EN
OX
(ppm
)
IMEP
CO
V(%
),SF
N41
5an
dC
O(%
)
300 360 420 480 540200
220
240
260
280
300
0
500
1000
1500
2000
2500
3000
3500
0
0.5
1
1.5
2
2.5
3
3.5
BSFC_KW (g/kW.h)ECO (%)EHC (ppm)ENOX (ppm)S415_FSN (-)EA_COV_of_IMEP
1500RPM Fixed Fuel, 8bar BMEPFixed Cams, High Lift
λ=1, UnthrottledMBT Knock Limited Spark
Opportunities for Valvetrain Optimization
0.4 FSN
Low lift operation vs Speed– Limited charge motion– Slow burn rates at unthrottled
conditions
Soot at high loads with gasoline
3
1
12
2
DYNSP (rpm)
BM
EP(k
Pa)
500 1000 1500 2000 2500 3000 3500 40000
200
400
600
800
1000
454035302520
E85 Unthrottled Speed Load MapLow lift
0 - 10 Burn Durations
0 - 10Burn Duration (°)
% IMEPCOV
HC 800 ppm
Charge Motion Indices for Intake Valvetrain
-0.5
0
0.5
1
1.5
2
2.5
3
Swirl Tumble Swirl Tumble
Cha
rge
Mot
ion
Inde
x
Low Lift2 Valves Active
High Lift2 Valves Active
0 00.5
1.6
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Valve DeactivationLow lift Deactivation
– Improved Charge Motion– Improved burn rates
Use of high lift deactivation reduces gasoline soot and HC
SOI (° aTDCf)
BSF
C(g
/kW
hr)
EHC
(ppm
),EN
OX
(ppm
)
IMEP
CO
V(%
),SF
N41
5an
dC
O(%
)
300 360 420 480 540200
220
240
260
280
300
0
500
1000
1500
2000
2500
3000
3500
0
0.5
1
1.5
2
2.5
3
3.5
BSFC_KW (g/kW.h)ECO (%)EHC (ppm)ENOX (ppm)S415_FSN (-)EA_COV_of_IMEP
1500RPM Fixed Fuel , 8 bar BMEPFixed Cams, High Lift Deac
λ=1, UnthrottledMBT Knock Limited Spark
11
1.51.51.5
1.5
2 2
DYNSP (rpm)
BM
EP(k
Pa)
500 1000 1500 2000 2500 30000
100
200
300
400
500
600
4542.54037.53532.53027.52522.520
E85 Speed Load MapLow Lift, Single valve deactivation
0 - 10 Burn Durations
0 - 10 Burn Duration (°)
<<0.1FSN
Charge Motion Indices for Intake ValvetrainComparison of 2 Valve vs. 1 Intake Valve
-1
0
1
2
3
4
5
6
7
8
Swirl Tumble Swirl Tumble
Cha
rge
Mot
ion
Inde
x
2 Valves1 Valve
Low Lift High Lift
HC 400 ppm
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Intake Valve Activation Strategies vs. Baseline
Low lift valve deactivation improves performance
Light throttle for EGR control superior to unthrottled operation
High lift deactivation optimal option for high load / low speed
Baseline is gasoline, 9.2:1 CR performance scaled to E85 LHV
%Im
prov
emen
t
5
10
15
20
25
2000 RPM Load Sweep - E85Intake Valve Deactivation vs. Two valves Active
High Lift and Low Lift
BSF
C(g
/kW
hr)
300
400
500
600
LL Unthrottled / 2VLL Deac. OptimizedLL 2V OptimizedHL Unthrottled / 2VHL 2V OptimizedHL Deac. Optimized
BMEP (kPa)
MA
P(k
Pa)
0 500 10000
20
40
60
80
100
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Engine Performance (Peak NA Torque) Blends Tested 91 RON E0 Blended with ethanol
– E0, E10, E20, E30, E40, E50, E85
High Ethanol Fuels E50-E85 did not require spark retard E0, E10 Require retard at all speeds
Engine Speed (RPM)
CA
50(°
)
0 1000 2000 3000 4000 50005
10
15
20
25
30
E85E50E20E10E0
Max Torque CurvesEthanol Blends
λ = 1, MBT Knock Limited Spark
Engine Speed (RPM)
BM
EP(k
Pa)
0 1000 2000 3000 4000 5000600
700
800
900
1000
1100
1200
1300
E85E50E20E10E0
Max Torque CurvesEthanol Blends
λ = 1, MBT Knock Limited Spark
deg
aTD
C
Effective CR Reduced for E0, E10 at low speed
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Conclusions
Reduced E85 fuel penalty from low energy density by 1/3 Valve deactivation improves flame speed and dilution
tolerance with EIVC Light throttle for EGR control more efficient than unthrottled
EIVC Valve deactivation reduces soot and HC for Gasoline at high
loads. E85 capable of improved low end torque. E20 Sufficient for 97% of peak torque with minimal retard.
– Minimal 7% Fuel density penalty
29SE2010 11
Acknowledgment
This material is based upon work supported by the Department of Energy under Award Number DE-FC26-07NT43270
» DOE Technology Development Manager: Kevin Stork» NETL Project Managers: John Jason Conley, Michael Ursic
– Delphi Powertrain; Tim Kunz, Cindy Tawaf, Ray Parker, Steve Crossman, Tom Verstraete, Tim Coha, Eunjoo Hopkins, David Yen, Randy Okenka. Carl McQuillen Racing
– Dr. Ming-Chia Lai, Dr. Xingbin Xie, Atsushi Matsumoto, Yi Zheng, Wayne State University, Detroit, MI
– Additional details will be presented at the 2011 SAE World congress in Detroit.– This report was prepared as an account of work sponsored by an agency of the United States Government. Neither the United States Government nor any agency
thereof, nor any of their employees, makes any warranty, express or implied, or assumes any legal liability or responsibility for the accuracy, completeness, or usefulness of any information, apparatus, product, or process disclosed, or represents that its use would not infringe privately owned rights. Reference herein to any specific commercial product, process, or service by trade name, trademark, manufacturer, or otherwise does not necessarily constitute or imply its endorsement, recommendation, or favoring by the United States Government or any agency thereof. The views and opinions of authors expressed herein do not necessarily state or reflect those of the United States Government or any agency thereof.