Numerical Analysis of Two-Stage Turbine System for Multicylinder Engine under Pulse Flow Conditions with High Pressure-Ratio Turbine Rotor

Internal combustion engine (ICE) exhaust gases provide a high amount of energy which is partially lost to the environment. Such can be recovered with turbocharger turbine or other after-treatment device. As flow varies not only load but also opening and closing valves, proper matching between should established maximize recovery waste energy. That why twin-scroll dual turbocharging system implemented, especially in multi-cylinder engines. systems require very complex pipeline eliminate interference pulses adjacent cylinder ignitions. In this study, two-stage, multi-channel was investigated for two different rotor geometries: old, high-performance A smaller more modern B, scaled match A. Both geometries were compared at three speeds variable geometry (VTG) vane positions. It found that two-stage B provided an 8% higher total efficiency than due lower losses within passage.