DYNAMIC CHARACTERIZATION OF TEMPERATURE SENSORS BY LASER EXCITATION

In this article, a new dynamic calibration technique for sensors used to measure flow temperature is developed. The technique is based on la ser heating of the sensor and allows one to operate in situ when optic al access to the sensor is provided and the flow is transparent to las er Light. It is possible to obtain both the time constant of the senso r and the convective heat exchange coefficient. Laboratory tests perfo rmed inside a wind tunnel, have shown the reliability and the advantag e of such a technique. It is also possible to reduce the uncertainty o n thermal exchange coefficient estimation (and therefore on the time c onstant) in order to obtain a more accurate model of the dynamic chara cteristics of the probes which are used for flow temperature measureme nts. (C) 1996 American Institute of Physics.