Use of optical fiber thermometers in high temperature environments

Radiation thermometry refers to the techniques and devices used to estimate the temperature of an object by measuring the radiative flux leaving the object. When properly implemented, radiation thermometry provides an accurate, precise and non-intrusive method for measuring temperature. Optical fiber thermometers (OFT) are a type of a radiation thermometer. Commonly used OFT are blackbody OFT and lightpipe radiation thermometers (LPRT). When a significant portion of the fiber is exposed to elevated temperatures, the temperature measurements are corrupted due to emission from the fiber. This paper describes a method that may be used to infer the temperature at the tip of the fiber and to estimate the temperature profile along the fiber when the fiber is exposed to a high temperature environment. Planned improvements for this method are also discussed.