Gasoline Powertrain Technologies: Pathways to CO 2 Emissions Reduction. John Kirwan Chief Scientist, Gasoline Engine Management Systems

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1 Gasoline Powertrain Technologies: Pathways to CO 2 Emissions Reduction John Kirwan Chief Scientist, Gasoline Engine Management Systems

2 Outline Global Powertrain Market Drivers CO 2 Reduction Technologies for Worldwide Application Summary and Conclusions 2

3 Outline Global Powertrain Market Drivers CO 2 Reduction Technologies for Worldwide Application Summary and Conclusions 3

4 NOx Emissions Standard, mg/km Powertrain Market Drivers: CO 2 Reduction with Low Tailpipe Emissions Global emissions legislation is evolving toward fuel-neutral standards, with emerging countries adopting European legislation Europe USA (federal) China (nationwide) Euro 4 Euro 5 Eu5+ Euro 6 Tier II bin 8 Tier II bin 5 (w/o OBD) Euro 2 Euro 3 Euro 4 (w OBD) NEDC Cycle 250 SI Engine Diesel Engine FTP Cycle NOx relief is disappearing for EU diesel engines Euro 4 Euro 5 / 5+ Euro 6 Tier2 Bin8 Tier2 Bin5 4

5 CO 2, g/km Powertrain Market Drivers: CO 2 Reduction with Low Tailpipe Emissions Global CO 2 / Fuel Economy Legislation Creates a Significant Challenge LD Truck United States CAFE Pass. Car China Fleet Avg. Europe Fleet Avg. EU / ACEA Agreeement DOT / EPA US National Standard: % 100% EU Comission Phase-in Car + Truck 35.5 MPG DOT / EPA / CA LEV3: US National Standard g/km EU Target 54.5 MPG Car + Truck Year 5

6 CO 2, g/km Powertrain Market Drivers: CO 2 Reduction with Low Tailpipe Emissions Global CO 2 / Fuel Economy Legislation Creates a Significant Challenge LD Truck United States CAFE Pass. Car China Fleet Avg. Europe Fleet Avg. EU / ACEA Agreeement DOT / EPA US National Standard: % 100% EU Comission Phase-in Car + Truck 35.5 MPG DOT / EPA / CA LEV3: US National Standard g/km EU Target 54.5 MPG Car + Truck Substantial innovation will be required Yearto reduce CO 2 while delivering features and performance expected by today s demanding customers 6

7 Outline Global Powertrain Market Drivers CO 2 Reduction Technologies for Worldwide Application Summary and Conclusions 7

8 Turbocharged Gasoline Direct Injection 8

9 CO 2 Reduction Technologies for Gasoline Engines Turbocharged Gasoline Direct Injection Engines Gasoline Direct Injection is a key enabler for improving low-end torque in boosted engines Improved volumetric efficiency and reduced knock propensity» Direct injection with cam phasing allows scavenging with fresh air to reduce residual gas fraction» In-cylinder fuel vaporization reduces charge temperature Improved combustion phasing» Charge motion increases burn rate Benefits Fuel economy improvement: 8% 15% Increased power and responsiveness Stoichiometric engine operation allows emissions control via traditional 3-way exhaust catalyst 9

10 CO 2 Reduction [%] CO 2 Reduction Technologies for Gasoline Engines Turbocharged Gasoline Direct Injection Engines Comparison: 1.6L 4-cylinder MPFI versus 1.2L 3-cylinder Turbo GDi and Turbo Diesel No electrification considered 3-cyl Boosted Engine Value Analysis No Lean Aftertreatment 25 Euro / % (with DeNOx) (with SCR) 50 Euro / % 15 3cyl. Turbo GDi EU cyl. MPFI EU4, 1160kg OEM - On Cost [Euro] Reference: SAE

11 CO 2 Reduction [%] CO 2 Reduction Technologies for Gasoline Engines Turbocharged Gasoline Direct Injection Engines Comparison: 1.6L 4-cylinder MPFI versus 1.2L 3-cylinder Turbo GDi and Turbo Diesel No electrification considered 3-cyl Boosted Engine Value Analysis Turbo GDi and Turbo Diesel engine comparison shows similar On Cost / % CO2 reduction No Lean Aftertreatment 25 Euro / % (with DeNOx) (with SCR) 50 Euro / % 15 3cyl. Turbo GDi EU cyl. MPFI EU4, 1160kg OEM - On Cost [Euro] Reference: SAE

12 CO 2 Reduction [%] CO 2 Reduction Technologies for Gasoline Engines Turbocharged Gasoline Direct Injection Engines Comparison: 1.6L 4-cylinder MPFI versus 1.2L 3-cylinder Turbo GDi and Turbo Diesel No electrification considered 3-cyl Boosted Engine Value Analysis Turbo GDi and Turbo Diesel engine comparison shows similar On Cost / % CO2 reduction No Lean Aftertreatment 25 Euro / % (with DeNOx) (with SCR) 50 Euro / % Lean NOx aftertreatment (if necessary) is a significant cost driver 15 3cyl. Turbo GDi EU cyl. MPFI EU4, 1160kg OEM - On Cost [Euro] Reference: SAE

13 Variable Valve Lift 13

14 CO 2 Reduction Technologies for Gasoline Engines 2-Step Variable Valve Lift and Timing 2-Step mechanization with cam phasing varies intake valve lift, duration and timing as a function of engine load 3-lobe cam provides two intake valve lift profiles Cam follower switches between high and low lift profiles Oil control valve hydraulically actuates switching Enables separate optimization of lowload and high-load intake events Optimized low-load profile with early intake valve closing (EIVC) substantially reduces pumping work losses for improved fuel economy (3%-6%) Optimized high-load phasing improves low-speed torque (2%-3%) and peak power (2%-4%) 2-Step Roller Finger Follower Arm Oil Control Valve Exhaust Low Lift Intake High Lift References: SAE ; SAE ; SAE ; SAE ; SAE

15 CO 2 Reduction Technologies for Gasoline Engines 2-Step Variable Valve Lift and Timing 2-Step mechanization with cam phasing varies intake valve lift, duration and timing as a function of engine load 3-lobe cam provides two intake valve lift profiles Cam follower switches between high and low lift profiles Oil pressure regulating valve controls switching 3-Lobe Cam 2-Step Roller Finger Follower Arm Pressure Regulating Valve Exhaust Intake Low Lift High Lift Animation of 2-step Operation 15

16 CO 2 Reduction [%] CO 2 Reduction Technologies for Gasoline Engines 2-Step Variable Valve Lift and Timing Comparison: 1.6L 4-cylinder MPFI versus 1.2L 3-cylinder Turbo GDi and Turbo Diesel No electrification considered 3-cyl Boosted Engine Value Analysis No Lean Aftertreatment 25 Euro / % (with DeNOx) (with SCR) 50 Euro / % cyl. Turbo GDi 2 step VVL EU6 3cyl. Turbo GDi EU6 Estimated 3% incremental benefit with 2-Step VVL 5 4cyl. MPFI EU4, 1160kg OEM - On Cost [Euro] Reference: SAE

17 Advanced Low Temperature Gasoline Combustion 17

18 Injection/Ignition Injection/Ignition Injection/Ignition Compression Compression Compression CO 2 Reduction Technologies for Gasoline Engines Advanced Combustion: Gasoline Direct injection Compression Ignition (GDCI) Combustion strategy High compression ratio (~15:1) and lean (with boost) for high thermal efficiency Central-mount, GDi-like injection pressure, multi-late injection strategy for partially pre-mixed combustion Gasoline has excellent fuel properties versus diesel fuel for this combustion mode» Higher volatility enables rapid vaporization» Higher octane number increases ignition delay to increase mixing time Low temperature combustion (lean with EGR) enables low engine out NOx and soot Medium CR Medium SI Engines CR SI Engines GDi-Homo Stratified Stratified Stratified HCCI-gas GDCI Lean SI Medium CR SI Engines Residuals EGR Residuals EGR Ignition Point Ignition Point Ignition Point Residuals EGR Residuals EGR Late Fuel Injection -Controlled Stratification Late Fuel Injection Lean -Controlled Stratification Ignition Lean Point DIESEL GDi-Homo GDi-Homo HCCI-gas HCCI-gas GDCI GDCI DIESEL Lean SI Lean SI Ignition Point Residuals EGR Ignition Point High CR CI Engines High CR CI Engi Residuals EGR Residuals Residuals EGR EGR Late Fuel Injection -Controlled Stratification Lean D 18

19 CO 2 Reduction Technologies for Gasoline Engines Advanced Combustion: Gasoline Direct-injection Compression Ignition (GDCI) Representative Single Cylinder Engine Results GDCI versus diesel on the same engine» A-B tests equally constrained for smoke and noise Efficiency evaluation» ISFC (vol.) worse than diesel due to higher diesel fuel density» ISFC (mass), thermal efficiency and CO 2 significantly improved over diesel GDCI, Triple Injection Diesel GDCI 4.5% worse 233 ISFC (vol) g/kw-hr GDCI 9.5% better ISFC (mass) g/kw-hr GDCI 8% better ITE x 10 % GDCI 10% better ISCO2 g/kw-hr 1500 rpm 6bar IMEP ISFC: Indicated specific fuel consumption ITE: Indicated thermal efficiency ISCO2: Indicated specific CO2 emissions Gasoline Diesel Density (g/cc) LHV (MJ/kg) CO2 (g/mj-hr) References: SAE ; SAE ; 20 th Aachen Colloquium on Automobile and Engine Technology, October,

20 Summary and Conclusions Global emissions and CO 2 mandates are driving substantial powertrain innovations to meet legislative requirements in fun-todrive vehicles Turbocharged GDi engines and 2-step variable valvetrain systems offer high-value CO 2 reduction strategies for gasolinefueled vehicles Low temperature GDCI combustion appears promising as a longer term strategy for diesel-like fuel efficiency in gasolinefueled engines 20

21 Thank You for Your Attention Innovation for the Real World