Application of a Raman distributed temperature sensor to theexperimental fast reactor JOYO with correction techniques

Abstract

In order to apply a Raman distributed temperature sensor (RDTS) to themonitoring of nuclear facilities, some correction techniques forradiation-induced errors were developed and investigated. One is a simplecorrection technique with two thermocouples, when uniform radiation-inducedloss distribution can be assumed. The other is a special technique with aloop-type arrangement. In this technique, even when the loss distributionis not uniform, radiation-induced errors can be cancelled.To demonstrate these techniques, RDTS has been installed at theexperimental fast reactor JOYO. During continuous measurements with a totaldose of more than 7.7×103 C kg-1 (3.0×107 R), the radiation-induced error showed a tendency to saturate and thefeasibility of the correction techniques was demonstrated. These resultsshow that RDTS could be useful as a temperature distribution monitor innuclear plants.