Cylinder Deactivation. ◊ Functionality ... Deactivation Valve Lifter Hardware
Animation .... Source: Schame (Ford): 2008 SAE Congress Presentation. Source:
...
CO2 Reduction for Spark-Ignition Engines: Two Paths to Success Leveraging Air Delivery and Fuel Injection Technologies to Improve Engine Efficiency
John E. Kirwan Delphi Powertrain Systems
High Level Gasoline Engine Technology Roadmap PZEV Market Drivers: EURO 5 EURO 5+ Emissions & CARB CO2 EU 130g/km Fuel Economy US Senate CAFE
EURO 6 EU 95g/km
EU 70g/km US CAFE Update H2 DI-Engine CNG DI-Engine Alternate cycles, VCR, camless
HCCI GDi Engine, DICP & VVA & eVCP Spray Stratified Boosted GDi Engines Spray Stratified GDi Engines Homogeneous, Boosted GDi Engines, DICP & VVA Homogeneous, Boosted GDi Engines, DICP Homogeneous GDi Hybrid Engines Homogeneous GDi Engines, VVT Alternate Fuel – H2 Engine Alternate Fuel – CNG, LPG Alternate Fuel Compatible Engine – Flex fuel, E10-E100 Boosted PFI Engines Gasoline Hybrid Engine Gasoline Advanced PFI Engine, active VT, mixture motion, PZEV Gasoline PZEV (AIR)
2008
2010
2012
2014 2
2016
2018
2020
Future
Where Does the Fuel Energy Go? Fuel Energy Available Heat Rejection
Combustion Inefficiency
Exhaust
Coolant Engine Friction Pumping Losses
Indicated Work
Accessories
Shaft Work
Transmission
Vehicle Consumption
Inertia Aero Drag Rolling Resistance Source: Nat’l Acad Eng. (2002)
3
Where Does the Fuel Energy Go? Fuel Energy Available Heat Rejection
Combustion Inefficiency
Exhaust
Coolant
Source: SAE 2003-01-0029
Engine Friction Pumping Losses
Indicated Work
Accessories
Shaft Work
Transmission
Vehicle Consumption
Inertia Aero Drag Rolling Resistance Source: Nat’l Acad Eng. (2002)
4
Where Does the Fuel Energy Go? Fuel Energy Available Heat Rejection
Combustion Inefficiency
Exhaust Target Domain: Improve Net Engine Efficiency
Coolant Engine Friction Pumping Losses
Indicated Work
Accessories
Shaft Work
Transmission
Vehicle Consumption
Inertia Aero Drag Rolling Resistance Source: Nat’l Acad Eng. (2002)
5
Fundamental SI Engine Control Parameters Fuel Energy Available
hTarget: Reduce pumping losses hMethods: q Valvetrain Technologies 8 Variable Cam Phasing 8 Cylinder Deactivation 8 Variable Valve Lift q Turbo / Supercharging
Combustion Inefficiency
Heat Rejection
◊ Air
Exhaust
Coolant
Source: SAE 2003-01-0029
Engine Friction Pumping Losses
Indicated Work
Accessories
Shaft Work
Transmission
Vehicle Consumption
Inertia Aero Drag Rolling Resistance Source: Nat’l Acad Eng. (2002)
◊ Fuel hTarget: Reduce heat rejection and pumping losses hMethods: q Homogeneous Gasoline Direct Injection q Stratified Gasoline Direct Injection
◊ Spark hTarget: Proper timing minimizes heat rejection; advanced ignition systems can enable higher dilution combustion strategies 6
Valvetrain Technologies
Variable Cam Phasing Functionality: Control air flow through valve timing to gain performance, emissions reduction and fuel economy Benefit Application Type Acronym
Schematic
Performance Fuel Economy
Emissions HC NOx
∆Ι
Intake Only
IVCP Exhaust
4-7%
1-2%
15%
25%
Stratified GDi
100
◊ Benefits
40
60
h Fuel economy improvement q 10-15% for naturally aspirated q 15-20% with downsizing and boost h Improved fuel control and rapid catalyst light-off with split-injection during cold start h Increased power and torque 27
80
100 120 Engine Power [kW]
140
160
◊ European strategy h Current barriers to US implementation: q More stringent NOx standards q Lean NOx catalyst durability q Fuel sulfur concentration
Gasoline Direct Injection Stratified Systems ◊ Key Requirements hOperation at fuel pressures up to 200 bar hLow noise in critical frequency range hWell-atomized and well-placed stratified mixture under engine conditions hMultiple injection capability hHigh linear flow range
Fuel Mass (mg/shot)
140
20%
fp = 200 bar
15%
120
10%
100
5%
80
0%
60
-5%
40
-10%
20
-15%
0 0.00
1.00
2.00 3.00 Injector Pulse Width (ms)
4.00
Deviation (%)
160
-20% 5.00
28
Stable spray under engine conditions 5 bar
10 bar Backpressure
20 bar
Summary ◊ Variable valvetrain technologies and gasoline direct injection offer technology improvements for two critical paths to CO2 reduction in SI engines h Attack pumping losses and heat rejection to improve net engine efficiency h Can be used to optimize alternative fuel performance and advanced combustion strategies (e.g. HCCI / CAI, highly dilute combustion)
◊ These innovations will substantially contribute to reducing fuel consumption required by Government and sought by customers h Applicable to wide spectrum of engine sizes / power needs h Offer simultaneous performance benefits so that CO2 reduction need not conflict with “fun-to-drive” vehicles Fuel Energy Available Heat Rejection
Combustion Inefficiency
Exhaust
Coolant
Source: SAE 2003-01-0029
Engine Friction Pumping Losses
Indicated Work
29
Accessories
Shaft Work
Transmission
Vehicle Consumption
Inertia Aero Drag Rolling Resistance Source: Nat’l Acad Eng. (2002)
Thank you
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