Hot-Gas Spin Testing of Ceramic Radial Turbine Rotor at TIT 1400 C

The reliability of silicon nitride radial turbine rotors for automotive gas turbine was evaluated with hot-gas spin test and reliability analysis. The turbine rotors were made of a newly developed silicon nitride, having a 4 point bending strength higher than 700 MPa at 1400°C. The turbine rotors withstood at a turbine tip speed of 500m/s at TIT 1400°C, the same level as the rated condition of turbine rotors for the two-shaft type automotive gas turbines. The reliability of turbine rotors is discussed in relation to the hot-gas spin test results and failure probability analysis using CARES program developed by NASA as well as three-dimensional flow analysis and finite element analysis.