Error of Measuring Surface Temperature of Turbine Blades With the Influence of Reflection by Monochromatic Method

A new method is proposed for correcting the error of monochromatic method in measuring the surface temperature of turbine blades with the influence of reflection. The measurement error caused by surrounding components was numerically investigated. The effects of background temperature, adjacent rotor blades, front stator vanes, and rear stator vanes on the temperature measurement error are described in detail. Furthermore, the corrected errors of high emissivity and low emissivity are compared and analyzed and the influence of the relative displacement between the turbine blade and the hot-end component on the temperature measurement error is also discussed. Benefiting from the proposed radiation-based error correction method (RECM), we can reduce the monochromatic temperature measurement error to less than 0.3% at high emissivity and less than 0.8% at low emissivity theoretically. Finally, the RECM method is studied experimentally, and the results show that the temperature measurement error can be corrected to better than 0.6%, which is in good agreement with the Monte Carlo simulation (MCS) results.