Detailed measurements of total temperature and velocity in high-speed, rotating turbo-machinery flows are difficult due to the high sensor frequency response required. Constant temperature hot-wires have the needed frequency response, but are sensitive to both T_t and effective wire pU which vary significantly in high speed flows. The multiple overheat method can be used to decouple the phase locked averages of T_t and wire effective pU from the phase locked average hot-wire voltages. The present study will demonstrate the efficacy of this technique as well as a detailed uncertainty analysis of the multiple overheat method. The overall uncertainty is primarily determined by: the quality of the hot-wire calibration, the frequency response of the constant temperature hot-wire system, and the ability of the turbomachinery facility to maintain a constant operating point while the hot-wire overheat values are changed. As a proof of concept, a single constant temperature hot-wire was operated at four different overheats at the exit of a transonic axial compressor rotor. The phase locked average T_t and wire effective pU fields show flow features relative to the rotor including blade wakes and tip clearance flows. These phase locked average measurements were validated against each other.
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