Combined scattering-referenced and co-doped aerosol phosphor thermometry using the Ce,Pr:LuAG phosphor

As a means of increasing the temperature range of high-precision measurements for aerosol phosphor thermometry (APT), the co-doped Ce,Pr:LuAG phosphor was investigated for use with simultaneous Pr3+-scattering-referenced APT (SRAPT), Ce3+-SRAPT, and co-doped APT techniques. Phosphor characterization was performed in a heated air jet at atmospheric pressure, and APT performance was estimated for the three simultaneous imaging techniques. A method for combining temperature measurements using a weighted average approach is discussed in detail and demonstrated via heated air jet imaging experiments. The combination of techniques results in a usable temperature range for the Ce,Pr:LuAG phosphor of 300 to at least 900 K, with better than 35 K estimated temperature precision from 500 to 900 K at a seeding density of 120 mm-3, improving diagnostic precision and temperature range over that of any single APT technique using the Ce,Pr:LuAG phosphor. The combination of SRAPT and co-doped measurements may improve the temperature range and performance of other similar phosphors as well.