Multiwire thermocouples in reversing flow

Measurements are recorded for multiwire thermocouples consisting of either two or three wires of unequal diameters. Signals from the multiwire probe are recorded for a reversing gas flow with both a periodic temperature and time constant fluctuation. It is demonstrated that the reconstructed signal from the multiwire thermocouple requires no compensation provided ω/ω1<2.3 for two wires or ω/ω1<3.6 for three wires where ω1 (=2πf) is the natural frequency of the smaller wire based on the maximum gas velocity. The latter results were possible provided Fourier transformed data from the wires were used and knowledge of the gas velocity phase angle was available.