Water radiolysis experiments using in-pile loop in JMTR

Hanawa, Satoshi ; Chimi, Yasuhiro; Nishiyama, Yutaka ; Nakamura, Takehiko 

Water radiolysis in reactor core is one of the key issues for safe and efficient LWR operation because chemical species formed by water radiolysis dominate corrosive environment of reactor core, and strongly influence integrity of structural materials in reactor as a result. Water chemistry in irradiation field can be evaluated by theoretical method, i.e. water radiolysis calculation, and confirmed by direct measurement of ECP. For demonstrating the adequacy of theoretical method, simulative calculation of in-pile ECP measurement and comparison between calculated and measurement results is essential. In order to provide significant information on water chemistry evaluation, experiments under well quantified condition will be performed in the JMTR. This paper presents out-lines and status of the experiments.