Radial Turbine Development for the 100 kW Automotive Ceramic Gas Turbine

Abstract

The development of turbine components for the automotive 100 kW ceramic gas turbine has entered the final stage of the seven-year project and is making satisfactory progress toward the goals. We have attained the interim targets of the aerodynamic performances and have been carrying out tests to further improve efficiency. As for ceramic parts, we have changed the material of the turbine rotor to a new one that is excellent in long-sustained and high-temperature strength properties, and have confirmed substantial strength at high temperature through hot-spin tests. After evaluating blade-vibration stress through analyses and experiments, we completed an endurance evaluation at 1200°C (1473 K) TIT (Turbine Inlet Gas Temperature) and a rated speed of 100,000 rpm. We are now carrying out endurance tests at 1350°C (1623 K) TIT. For ceramic stationary parts, we already finished the evaluations at 1200°C TIT and are also conducting an endurance test at 1350°C TIT. Using these parts in a full-assembly test, together with other elements, we confirmed that they cause no functional problem in tests performed at 1200°C TIT level up to the rated speed (100,000 rpm), and are evaluating their performances.