Development of experimental database for decay heat removal system of sodium-cooled fast reactor; Uncertainty evaluation of temperature measurement data in PLANDTL-2 experiment

Akimoto, Yuta ; Ezure, Toshiki ; Onojima, Takamitsu; Kurihara, Akikazu 

In order to improve the reliability of the experimental database for a decay heat removal system in sodium-cooled fast reactors, uncertainty evaluation of temperature measurement data in thermal hydraulic experiments using sodium as the working fluid was investigated using the sodium experimental facility PLANDTL-2. In this study, an evaluation method of uncertainty due to the influence of the heat loss from the test section and the uncertainty of reference thermocouples was proposed for the relative calibration of thermocouples fixed inside the test section of PLANDTL-2. Moreover, the method has also been applied to the temperature measurement data of PLANDTL-2 experiment, and the confidence interval was evaluated to confirm the applicability of the method.