2018 Schaeffler Symposium Jerry Dixon - The Next Generation of Valve Train 9/6/2018 THE NEXT GENERATION OF VALVE TRAIN JERRY DIXON

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1 THE NEXT GENERATION OF VALVE TRAIN JERRY DIXON 1

2 WHAT SHOULD BE EXPECTED FROM THE NEXT GENERATION OF VALVE TRAINS? Next Generation Valve Train Expectations 1 Improved Performance 2 Modularity / Flexibility 3 Synergies with Hybrids 4 Cost / Benefit 2

3 erocker System UniAir System erocker System UniAir System 3

4 Requirement Specification for an Up-To-Date Switchable Valve Train System Hydraulic Switchable Roller Finger Follower + Cost effective + Installation space - Oil supply dependent - Deeply integrated in engine Cam Shifting System 2-Step + Modular + Oil supply independent - Installation space - Costs Electromechanical Switchable erocker System Finger Follower System + Oil supply independent + Cost effective + Easy to implement in existing cylinder heads + Modular + Gasoline: cylinder deactivation + Diesel: secondary exhaust valve Lift Requirement Specification for an Up-To-Date Switchable Valve Train System Hydraulic Switchable Roller Finger Follower + Cost effective + Installation space - Oil supply dependent - Deeply integrated in engine Cam Shifting System 2-Step + Modular + Oil supply independent - Installation space - Costs Electromechanical Switchable erocker System Finger Follower System + Oil supply independent + Cost effective + Easy to implement in existing cylinder heads + Modular + Gasoline: cylinder deactivation + Diesel: secondary exhaust valve Lift 4

5 Evolution from Hydraulic SRFF to erocker System Hydraulic SRFF System erocker System Hydraulic SRFF to Mechanical SRFF Oil Circuit to Slider Bar Solenoid Valve to Solenoid Actuator erocker System for Cylinder Deactivation (CDA) 5

6 Switching Time Measurement Hydraulic app. 1 Hydraulic app. 2 erocker System Switching time in ms Temperature in C Switching Time Measurement Hydraulic app. 1 Hydraulic app. 2 erocker System Switching time in ms Temperature in C Lowest switching time variation Optimization independent of oil pressure 6

7 erocker System Integration SRFF Slider Actuator Simple application advantageous installation space No oil circuit leads to less cylinder-head changes erocker System Single-Cylinder Module Single-Cylinder Module Single-Cylinder Module provides more flexibility Enabler for Rolling Cylinder Deactivation (RCDA) 7

8 erocker System Single-Cylinder Module + Actuators + SRFF + Cyl. head cover and connections Top view on cylinder head with actuation mechanics, no SRFF mounted Large test actuators - SRFF mounted but hardly visible Ready for test run erocker System Single-Cylinder Module Actuator Slider System activated Slider is pushed CDA mode is active No CDA CDA No CDA Single-Cylinder Module provides the same functionality as the full erocker System 8

9 erocker System Benefits with P0/P1 Hybrid Function Potential Application on I4 Recuperation Drag-torque reduction by CDA 1000 rpm: -30% 3500 rpm: -25% Drag torque / Nm -30 % -25 % Start-stop functionality / coasting Smooth engine restart Reduce energy consumption for restart Engine speed / rpm Strategies currently under investigation erocker System Benefits with P0/P1 Hybrid Advanced Function Potential Application on I4 Valve deactivation during overrun Avoiding GPF / catalyst purge during coasting 3-7 % CO 2 benefit in WLTC Various strategies currently under investigation 9

10 Next Generation System Summary 1 Improved Performance 2 Modularity / Flexibility 3 Synergies with Hybrids 4 Cost / Benefit erocker System UniAir System 10

11 UniAir Principle Pressure accumulator Solenoid valve Pump-unit (master cylinder) Additional pump-lobe Slave cylinder with brake-unit Mechanically linked UniAir Principle Pressure accumulator Solenoid valve Pump-unit (master cylinder) Additional pump-lobe Slave cylinder with brake-unit UniAir actuator Hydraulically linked 11

12 UniAir Principle UniAir Principle 12

13 UniAir Principle Actuation Information Camshaft signal Temperature signal Crankshaft signal Mechanical / Hydraulic system with solenoids as virtual sensor UniAir embedded software Valve control module fully integrated in ECU Lift-Mode Development Generation III Generation II Generation I Full lift / No lift Early valve closing Late valve opening Multi-lift Boot lift Early valve closing Late valve opening Multi-lift Hybrid lift + Reverse boot lift Multi-lift / Hybrid lift 13

14 Steady-State Benefit Summary WLTC benefit 1 of UniAir with conventional powertrains Fuel Consumption Improvement [%] 1 WLTC simulated with measured 3-cyl. engine maps (with & without UniAir) and based on C-Segment passenger car; No VCT for UniAir applications Results from actual engine map testing Primary improvements through pumping loss reduction Baseline 1 dual VCT, no UniAir UniAir only 1 14

15 Gasoline Engine Map: 3 Regions of Benefit for UniAir ICE operation points Engine torque in Nm Idle Engine speed in rpm Gasoline Engine Map: 3 Regions of Benefit for UniAir ICE operation points Pumping losses Engine torque in Nm Idle Naturally aspirated operation Engine speed in rpm 15

16 Part-Load Strategies for UniAir ICE operation points Pumping losses Engine torque in Nm Idle/ Torque reserve Boot lift Hybrid lift Early/Late valve closing Cylinder Deactivation Engine speed in rpm Gasoline Engine Map: 3 Regions of Benefit for UniAir ICE operation points Pumping losses Engine torque in Nm Charged operation Knocking limitation Idle Naturally aspirated operation Engine speed in rpm 16

17 Medium Engine Load Strategies for UniAir ICE operation points Engine torque in Nm Charged operation Early valve closing Late valve closing Knocking limitation Idle Naturally aspirated operation Engine speed in rpm BSFC in g/kwh Benefits at Medium Engine Loads Baseline Medium engine load: 2000 rpm / 13 bar Miller and Atkinson strategies reduces knocking tendency of engine Allows advanced ignition timing Nearly optimum Center of Combustion (MBF50) possible Improved fuel consumption 2 1 MBF50 in CA Operating point: IVO = const. Engine valve closing in CA 17

18 Gasoline Engine Map: 3 Regions of Benefit for UniAir ICE operation points Pumping losses Engine torque in Nm Charged operation Knocking limitation Exhaust temperature limitation Idle Naturally aspirated operation Engine speed in rpm Full Engine Load (Maximum Power) Strategies for UniAir ICE operation points Early/Late valve closing Engine torque in Nm Charged operation Exhaust temperature limitation Idle Naturally aspirated operation Engine speed in rpm 18

19 Full-Load Operation / Optimization of Geometric Compression Ratio IVC in CA (0.2mm) BSFC in g/kwh Lambda Limit MBF50 < 30 CRK Speed: 5000 rpm BMEP: 22 bar CR: T₃: 1020 C P₀: 1015 mbar T₀: 25 C Base engine Rated Power: 5000 rpm / 22bar Reduced effective CR with Miller valve timing Enables increased geometric CR with identical max power ( ) No full-load enrichment (λ=1) Up to 20% CO₂ reduction IVO in CA (0.2mm) Fully variable intake valve closing enables higher CR and corresponding BSFC benefit in part load Steady-State Benefit Summary WLTC benefit 1 of UniAir with conventional powertrains Fuel Consumption Improvement [%] 1 WLTC simulated with measured 3-cyl. engine maps (with & without UniAir) and based on C-Segment passenger car; No VCT for UniAir applications Results from actual engine map testing Primary improvements through pumping loss reduction Baseline 1 dual VCT, no UniAir UniAir only 1 19

20 Steady-State Benefit Summary WLTC benefit 1 of UniAir with conventional powertrains Fuel Consumption Improvement [%] 1 WLTC simulated with measured 3-cyl. engine maps (with & without UniAir) and based on C-Segment passenger car; No VCT for UniAir applications Additional to steady-state benefits No UniAir HW changes required Fully utilize the speed of UniAir to maximize transient benefits Baseline 1 dual VCT, no UniAir UniAir UniAir + only 1 increased CR UniAir Benefits During Transient Engine Operation FC benefit in WLTC Fuel Consumption Improvement [%] Additional 3.8% improvement derived from test and simulations Air path becomes fasttorque path Avoids ignition retard during transient operation Avoids catalyst purge at fuel cutoff Transient benefits are in addition to steady state Base engine Avoid catalyst purge Transient torque control Torque reserve min air charge 20

21 Steady-State and Transient Benefit Summary WLTC benefit 1 of UniAir with conventional powertrains Fuel Consumption Improvement [%] 1 WLTC simulated with measured 3-cyl. engine maps (with & without UniAir) and based on C-Segment passenger car; No VCT for UniAir applications Additional to steady-state benefits No UniAir HW changes required Fully utilize the speed of UniAir to maximize transient benefits Baseline 1 dual VCT, no UniAir UniAir UniAir + only 1 increased CR Steady-State and Transient Benefit Summary WLTC benefit 1 of UniAir with conventional powertrains Fuel Consumption Improvement [%] 1 WLTC simulated with measured 3-cyl. engine maps (with & without UniAir) and based on C-Segment passenger car; No VCT for UniAir applications 2 WLTC in order to show the dynamic advantages of the UniAir, only for this case, it was simulated a vehicle with manual transmission Transient benefits are additional No UniAir HW changes required Fully utilize the speed of UniAir to maximize transient benefits Baseline 1 dual VCT, no UniAir UniAir UniAir + only 1 increased CR UniAir + Increased CR + transient benefits 21

22 Hybrid Synergies: Drag-Torque Reduction and Avoid Catalyst Purge Drag torque in Nm Mech. base engine Drag torque = Nm Exhaust mass flow in g/s Mech. base engine Exhaust mass flow = 2.2 g/s IVO in CA (0.2mm) Drag torque in Nm Exhaust mass flow in g/s UniAir can reduce the drag torque during fuel cutoff IVO in CA (0.2mm) Speed = 1500 rpm Hybrid Synergies: Drag-Torque Reduction and Avoid Catalyst Purge Drag torque in Nm Mech. base engine Drag torque = Nm Exhaust mass flow in g/s Mech. base engine Exhaust mass flow = 2.2 g/s IVO in CA (0.2mm) Drag torque in Nm Exhaust mass flow in g/s IVO in CA (0.2mm) Speed = 1500 rpm UniAir can reduce the drag torque during fuel cutoff No oxygen flow into the fuel cutoff 22

23 Simulation Results WLTC Conventional vs. P1 (P0) Hybrid Conventional vehicle 6.0% Maintains transient and CR increase benefits Fuel consumption in l/100km Base engine UniAir 11.7 UniAir 13.5 P0/P1 Vehicle Additional pumping-loss reduction during load shifting Improve recuperation efficiency by minimizing drag torque up to 30% Avoid catalyst purge after fuel cutoff Base engine UniAir 11.7 UniAir 13.5 Simulation Results WLTC Conventional vs. P2 Hybrid Conventional vehicle 6.0% Maintains transient and CR increase benefits Fuel consumption in l/100km Base engine UniAir 11.7 UniAir 13.5 P2 Vehicle Additional pumping-loss reduction during load shifting Avoid catalyst purge Improved Stop/Start behavior Base engine UniAir 11.7 UniAir

24 Steady-State, Transient and Hybrid Benefit Summary WLTC benefit 1 of UniAir with conventional powertrains Fuel Consumption Improvement [%] 1 WLTC simulated with measured 3-cyl. engine maps (with & without UniAir) and based on C-Segment passenger car; No VCT for UniAir applications 2 WLTC in order to show the dynamic advantages of the UniAir, only for this case, it was simulated a vehicle with manual transmission Transient benefits are additional No UniAir HW changes required Fully utilize the speed of UniAir to maximize transient benefits Baseline 1 dual VCT, no UniAir UniAir UniAir + only 1 increased CR UniAir + Increased CR + transient benefits Steady-State, Transient and Hybrid Benefit Summary WLTC benefit 1 of UniAir with conventional powertrains Fuel Consumption Improvement [%] P0/P1 benefit P2 benefit 1 WLTC simulated with measured 3-cyl. engine maps (with & without UniAir) and based on C-Segment passenger car; No VCT for UniAir applications 2 WLTC in order to show the dynamic advantages of the UniAir, only for this case, it was simulated a vehicle with manual transmission Baseline 1 dual VCT, no UniAir UniAir UniAir + only 1 increased CR UniAir + Increased CR + transient benefits UniAir + Increased CR + P0 or P1 UniAir + Increased CR + P2 24

25 Next Generation System Summary 1 Improved Performance The Next Generation of Valve Train Is Here! 2 Modularity / Flexibility Schaeffler will continue to innovate to develop the generation after this 3 Synergies with Hybrids 4 Cost / Benefit 25