Turbocharged Spark Ignited Direct Injection A Fuel Economy Solution for the US June 10, 2009

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1 Turbocharged Spark Ignited Direct Injection A Fuel Economy Solution for the US June 10, 2009 Paul Whitaker Chief Technologist, Gasoline Engines AVL Powertrain Engineering Inc.

2 Global Gasoline Technology Trends Technology Micro PC Engines < 1,0 l Small PC Engines 1,0-1,5 l Medium PC Engines 1,5-2,4 l Large PC Engines > 4 cyl LDT / MDT Truck General Market Trends: Variable Charge Motion Variable Valve Lift 2 / 3 Step New /current Mainstream: Variable Valve Lift Continuous? Cylinder Deactivation? NA Homogeneous SIDI TC Homogeneous SIDI SIDI Stratified Controlled Auto Ignition??????? 2

3 SIDI + Turbocharging Low End Torque versus Mid / High Speed BSFC BMEP [bar] MY 2005 MY 2007 I-VCP MY 2010 DVCP MY VGT BSFC [g/kwh] 0 t turb = 950 C RON Engine Speed [rpm]

4 High Tumble for Turbo SIDI Octane and Faster Burn Rate Benefits with High Tumble Improves Full-Load Fuel Consumption 4

5 Optical Engine Supports Turbo SIDI Programs Example: 1500 rpm Boosted Full Load Optimization Optimized System LIF Base System Air intake flow Fuel spray direction Flame Images Good Injector: flame intensity NO soot flames! HEAVY soot flames! 5

6 Enrichment Requirement for Turbocharged Gasoline Engines Full Load, Ultra High Performance Concepts 30 Enrichment RON 95 Enrichment RON 98 Full Load State of art Measures to reduce enrichment requirement: High RON fuels Higher temperature turbine (e.g.: 950 C 1050 C) Engine Speed [rpm] Cooled external EGR Active exhaust gas cooling 6

7 Showing The Potential Of Turbocharged GDI Increased full load performance allows longer final drive ratio for improved fuel economy AVL 2.0l Turbo SIDI L VW FSI 2.0L AVL t-gdi 2.0L VW Diesel Engine Torque - Nm l Turbo SIDI (Production) NEDC l/100km NEDC g/km CO NEDC $/mile* FTP 75: 32 mpg HWFET: 50 mpg GDI-Turbo Concept Car for low Fuel Consumption Engine Speed rpm 6000 NEDC $/mile* based on $3.55/gallon for premium gasoline & $4.15/gallon ultra low sulfur diesel US average prices 22-APR-08 7

8 Ethanol Turbocharged Direct Injection Regular Gasoline Ethanol / Lower Heating Value (MJ/kg) x Heat of Evaporation (kj/mj)

9 Multiple Injection Strategy for E100 Cold Start Turbo SIDI Single Injection Fuel pressure 4 bar Fuel pressure 40 bar Intake valve Injector Large droplets Small droplets Small droplets New Multiple Injection Fuel Pressure 40 bar After SOI After SOI First Injection Early Last Injection Late No wall film Minimised Piston Wetting After EOI EOI Wall film Significantly reduced wall film 9

10 Turbo SIDI - Benefits of E85 on Full Load Operation 2.5% 30 CA MBT 150 bar 950 C 25% E85 RON91 10

11 Dual Fuel Strategy E85 provides significant octane benefit with DI due to high latent heat of vaporization and high octane rating Allows knock-free operation at high CR and high BMEP with very high thermal efficiency but Low E85 heating value is a disadvantage % E % E85 BMEP [bar] % E85 10% E85 Dual fuel strategy uses E85 DI only as required to eliminate knock in a high CR gasoline engine Engine Speed [rpm] Combines high load E85 octane benefit with part load gasoline heating value advantage Provides maximum leveraging of available ethanol 11

12 Dual Fuel Optimized E85 Engine vs. Competitors Cycle Simulation Results Medium Duty Truck mpg E mpg Urea Max Grade in 6th Gear at 65 mph (%) Heating Value Disadvantage Downsizing/Downspeeding Benefit +3 Compression Ratio Increase, Advanced Combustion Phasing Benefits Gasoline Displaced By E85 At High Load 5.0l GTDI 91 RON 5.0l GTDI FFV E85 5.0l Dual Fuel (gasoline mpg only) NA Gasoline Baseline 91 RON Diesel Target Metro Highway Fuel Economy Improvement (%) 12

13 Optical Engine - Split Injection for Catalyst Heating Comparison of Gasoline & E85 Flame Images Gasoline DI 100 Soot Flame 1 Flame Probability 100 [%] Premixed Flame 0 E85 DI Significantly reduced smoke with E85 (oxygenated fuel) more calibration freedom, increased efficiency 13

14 Summary Turbocharged SIDI is the most promising fuel economy technology for US: Combines existing & proven technologies in a synergistic manner Offers double digit fuel economy benefits Much lower cost than diesel or hybrid Can meet future emissions standards with inexpensive gasoline aftertreatment Can be applied across an OEM s entire engine portfolio in high volume Provides benefits when operating on ethanol in Flex Fuel applications Dual fuel (PFI gas + DI ethanol) concept new benchmark for SI fuel economy 14