ABSTRACT
Automotive turbocharger suppliers are continuing to refine their product portfolio to meet increasingly stringent emission regulations. IHI developed the double scroll turbine concept as one of the technologies suitable for the high-specific-power market segment of passenger vehicles. Despite the recent market introduction of this technology, its 1D gas exchange modelling methodology remains largely underrepresented in the relevant literature. In this paper, extensive experimental data are used to improve the steady-state turbine mapping. Furthermore, 1D modelling methodologies are validated against experiments under pulsating flow conditions. Finally, it is concluded that the turbine wheel can be treated as a quasi-steady component while any unsteadiness of the turbine stage can be considered to be due to mass storage effects in the turbine volute. On top of this, the effect of windage (ventilation) loss is not negligible in case of double scroll turbine under low frequency pulsating flow condition. By considering aforementioned points, an improvement of engine performance predictability is confirmed.
