Mitsubishi Heavy Industries Technical Review
    Vol. 50 No. 1 (2013)   New Products & Technologies
    Technical Papers

    Development of Twinscroll Turbine for Automotive Turbochargers using Unsteady Numerical Simulation

    Katsuyuki Osako,
    Takao Yokoyama,
    Toyotaka Yoshida,
    Toru Hoshi,
    Motoki Ebisu,
    Takashi Shiraishi

    In recent years, in response to growing interest in environmental issues, many automotive technologies for fuel efficient vehicles and countermeasures for emission control have been developed. Among such technologies, turbochargers have been increasingly used for the downsizing of engines. It is necessary for the further enhancement of fuel efficiency to improve the efficiency of turbochargers. However, the radial turbines used for turbochargers operate under conditions of pulsing exhaust. Because large pulsation makes the flow unsteady, it has been difficult to understand flow phenomena and improve efficiency. MHI uses unsteady computational simulation to understand complex flow phenomena. Based on this, MHI has refined a twin scroll to improve flow in the scroll and rotor blade, and then developed a more efficient twin scroll turbine.