Temperature profiles for axially symmetrical distributions using integrated optical fiber sensing

摘要

The temperature distributions for some hot gaseous systems are axially symmetrical. Examples include the air convected about a heated point or cylindrical source and gas discharges contained in cylindrical tubes. Such temperature distributions may be determined using an integrated optical fiber sensing technique, in which the fiber of one arm of an optical fiber interferometer passes along a chord of the hot gas system, and the measured phase shift provides an integrated temperature along the chord. By repeating this measurement for chord positions throughout the axially symmetrical temperature distribution, and carrying out an Abel transformation of the resultant data, a radial temperature profile can be determined. The integrated optical fiber sensing technique has been applied to the convected air flow above a small volume source of heat. The radial temperature profiles measured using the integrating sensor were compared with profiles obtained using an optical fiber probe sensor, a thermocouple and an unbound laser interferometer. The results reveal many advantages for the integrated optical fiber sensor in respect of precision, resolution and convenience of use.