Further development of two-stage turbocharging systems for large engines

Content Development of the second generation Power2 Case studies Medium-speed engine High-speed engine Conclusions © ABB Group September 20, 2018

Requirements and main design targets Development of the second generation Power2 Case studies Medium-speed diesel engine High-speed diesel engine Conclusions Pressure ratio up to 12 System efficiency over 75% Low emissions, low fuel consumption Low thermal load Large compressor map width High flexibility for various engine concepts High specific volume flow rates Compact design High natural frequencies, high reliability and optimal mounting on engines Designed for service Downtimes comparable to single- stage turbochargers © ABB Group September 20, 2018

Power2 800-M design features Extractable cartridge concept Development of the second generation Power2 Case studies Medium-speed diesel engine High-speed diesel engine Conclusions The big plus of the new extractable cartridge concept No disconnection of any gas or air flange connections required No disconnection of oil piping required No removal of any insulation parts required All service work can be done from the “cold” side Less dependency on cranes © ABB Group September 20, 2018

Power2 800-M design features Compactness Development of the second generation Power2 Case studies Medium-speed diesel engine High-speed diesel engine Conclusions Very compact designs for high- and low-pressure turbochargers Optimum in axial length; limited by flange dimensions only Air and gas casings CFD optimized Air inlet Air outlet Gas outlet Gas inlet Power2 800-M LP © ABB Group September 20, 2018

Compressor development Power2 800-M Compressor development 2012 LP - compressor 2010 - 2013 HP compressor Development of the second generation Power2 Case studies Medium-speed diesel engine High-speed diesel engine Conclusions Limitation by inlet Mach number Limitation by blade length © ABB Group September 20, 2018

Power2 800-M Compressor stages Development of the second generation Power2 Case studies Medium-speed diesel engine High-speed diesel engine Conclusions High pressure compressor stage for pressure ratio up to 12 Single-stage turbocharging A100-M axial Two-stage turbocharging Power2 800-M low-pressure compressor stage High pressure compressor stage for pressure ratio up to 10 © ABB Group September 20, 2018

Power2 800-M Turbine stages Design target low pressure turbine High efficiency at similar range of specific flow areas compared to single- stage turbines Design target high pressure turbine Very large range of specific flow areas at similar performance compared to single-stage turbines Two-stage turbocharging Power2 800-M High pressure turbine Two-stage turbocharging Power2 800-M Low pressure turbine Single-stage turbocharging Single-stage turbocharging © ABB Group September 20, 2018

Overall system performance Power2 800-M Overall system performance Overall performance comparison of A100-M and Power2 800-M system Development of the second generation Power2 Case studies Medium-speed diesel engine High-speed diesel engine Conclusions TIC= 55°C TIC= 70°C TIC= 55°C TIC= 70°C Two-stage turbocharging Power2 800-M Pressure ratio up to 12 Two-stage turbocharging Power2 800-M Pressure ratio up to 9 Single-stage turbocharging A100-M axial TIC = Intercooler temperature © ABB Group September 20, 2018

Cases definition BMEP = 25 bar Case A – single stage, no Miller Development of the second generation Power2 Case studies Medium-speed diesel engine High-speed diesel engine Conclusions Case A – single stage, no Miller Case B – single stage, maximum Miller Case C – 2-stage, same Miller as case B Case D – 2-stage, optimum Miller and variable valve timing © ABB Group September 20, 2018

Turbocharging system dimensions Development of the second generation Power2 Case studies Medium-speed diesel engine High-speed diesel engine Conclusions 2-stage size decrease 1-stage size increase © ABB Group September 20, 2018

The part load problem Basics Development of the second generation Power2 Case studies Medium-speed diesel engine High-speed diesel engine Conclusions High pressure and high efficiency lead generally to a stronger pressure reduction at part load This is due to the combined effects of efficiency and turbine area. These effects are described by the part load parameter: © ABB Group September 20, 2018

FPP operation VVT VVT VVT Development of the second generation Power2 Case studies Medium-speed diesel engine High-speed diesel engine Conclusions VVT VVT VVT © ABB Group September 20, 2018

Variable speed operation with variable valve timing Development of the second generation Power2 Case studies Medium-speed diesel engine High-speed diesel engine Conclusions lC at BMEP = 10 bar is considered representative for the possibility to run an operating line © ABB Group September 20, 2018

Load change 0-100% at constant speed Transient operation Load change 0-100% at constant speed Development of the second generation Power2 Case studies Medium-speed diesel engine High-speed diesel engine Conclusions Case D with variable valve timing can achieve the load change much faster than in the reference case © ABB Group September 20, 2018

Influence of pressure split Transient operation Influence of pressure split Development of the second generation Power2 Case studies Medium-speed diesel engine High-speed diesel engine Conclusions Increasing the pressure ratio of the HP stage gives a slower load change © ABB Group September 20, 2018

Load acceptance 0-100% in 2 steps Transient operation Load acceptance 0-100% in 2 steps Development of the second generation Power2 Case studies Medium-speed diesel engine High-speed diesel engine Conclusions © ABB Group September 20, 2018

Case studies Evaluation Case A B C D Compactness    Development of the second generation Power2 Case studies Medium-speed diesel engine High-speed diesel engine Conclusions Case A B C D Compactness    Engine efficiency       Part load Transient performance Nox emissions Potential for power increase 2-stage turbocharging is only attractive when a large step in pressure ratio is achieved in connection with variable Miller timing © ABB Group September 20, 2018

Conclusions Power2 800-M HP Power2 800-M system is based on a completely new extractable cartridge concept Focus on minimal service downtime supported by a new service tool concept Focus on compact and reliable design Two turbines and two compressors newly designed Every component optimized for a two-stage system without compromise High performance level and flexibility is achieved Two case studies have shown that a consistent pressure ratio increase is necessary to exploit the full potential of the new turbocharging system Development of the second generation Power2 Case studies Medium-speed diesel engine High-speed diesel engine Conclusions Power2 800-M LP © ABB Group September 20, 2018