CIMAC Circle @ POWER GEN / Cologne, 2014-06-03 Advanced turbocharging and variable valve timing for improving engine performance CIMAC Circle @ POWER GEN, 2014 Advanced turbocharging and VVT Topics § State-of-the-art gas engines § Advanced turbocharging and VVT • Engine performance enhancement © ABB Group / ABB Turbocharging May 30, 2014 | Slide 2 | filename State-of-the-art Gas Engines Main characteristics Turbocharging § Mainly 1-stage (first applications 2-stage) § Pressure ratios up to ~5.5 (~6.5) § Turbocharger efficiencies 65 – 68% (73%) Valve timing § Fixed valve timing or simple «2-step» § Miller timing Others § Throttle valve, waste gate and/or compressor bypass for lV control § Compression ratios of 12 to 13 © ABB Group / ABB Turbocharging May 30, 2014 | Slide 3 | filename Miller State-of-the-art Gas Engines Limitations, challenges Low engine compression ratio due to knocking Earlier Inlet Valve Closing (stronger Miller) Lower compression end temperature Reduced valve lift height cam defined closing ramps Increased knock margin «loss-generating» control devices demanding turbocharging efficiencies Increased compression ratio hE ↑ © ABB Group / ABB Turbocharging May 30, 2014 | Slide 4 | filename hE ↓ Increased throttling losses Increased control margin for part load Advanced Turbocharging Two-stage turbocharging § Pressure ratios of up to 12 § Turbocharging efficiencies above 75% § With higher pressure ratio … DhTC Þ Basic potential tintercooling 25°C tintercooling 60°C Þ … increase in DpCyl Þ … more compact 2-stage system DpCyl Þ Þ … increase in hTC Texh const 77% 75% 68% hTC = 65% Pressure ratio [-] © ABB Group / ABB Turbocharging May 30, 2014 | Slide 5 | filename Þ Advanced Variable Valve Timing Valve Control Management (VCM) No lift Valve Lift [mm] VCM Variation from cycle-to-cycle +60% 300 320 340 © ABB Group / ABB Turbocharging May 30, 2014 | Slide 6 | Teknologiateollisuus 20130507 360 380 400 420 Crank Angle [°CA] 440 460 480 500 520 Advanced Variable Valve Timing Valve Control Management (VCM) No lift Valve Lift [mm] VCM 300 320 340 © ABB Group / ABB Turbocharging May 30, 2014 | Slide 7 | Teknologiateollisuus 20130507 360 380 400 420 Crank Angle [°CA] 440 460 480 500 520 Advanced Variable Valve Timing Opportunities Low engine compression ratio due to knocking Earlier Inlet Valve Closing (stronger Miller) Increased valve lift height Lower compression end temperature Increased knock margin Increased compression ratio advance variable valve timing (VCM) high pressure 2-stage turbocharging (Power2) hE ↑ © ABB Group / ABB Turbocharging May 30, 2014 | Slide 8 | filename hE ↑ Minimized throttling losses Replacement of conv. control devices Engine Performance Enhancement Efficiency – Miller / TC efficiency variation § § e = 16; VCM - - - limitation knocking Const bmep Const heat release (partly TC efficiency) hTC 78% 75% 2-stage 70% 0.5 65% 1-stage; hTC ~65%; e = 13; fix cam 2-stage; hTC ~73%; e = 13; fix cam Schematic view © ABB Group May 30, 2014 | Slide 9 Miller ® 1-stage Engine Performance Enhancement Transient VCM: +60% power at the next working cycle 0.8 0.7 Conventional: +10% power by opening the throttle valve 0.6 0.5 1.0 2.0 Schematic view © ABB Group May 30, 2014 | Slide 10 3.0 4.0 5.0 Engine Load 6.0 7.0 Cylinder Output Delivery Ratio [-] 0.9 Advanced Turbocharging and VVT Summary potentials § Engine efficiency improvements by: § replacing conventional control elements § enabling high compression ratios § full utilization of 2-stage turbocharging § Superior transient capabilities § Better pZmax utilization by cylinder balancing and increased knock margin § Acceptance of lower Methane numbers (à less de-rating, standardization) © ABB Group / ABB Turbocharging May 30, 2014 | Slide 11 | filename © ABB Group May 30, 2014 | Slide 12
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