[2K01-05] Devices and Systems for Measurements and Human Factors

[2K02] Study of Neutron Instrumentation System in Pool type SFR

*Takashi Shoji¹, Hitoshi Okazaki¹, Yoshitaka Chikazawa² (1. MFBR, 2. JAEA)

Keywords:Sodium-cooled fast reactor, Pool-type reactor, Neutron instrumentation system

Neutron Instrumentation System (NIS) suitable for a pool-type SFR is being studied. The NIS is an indispensable for monitoring the reactor from the shutdown state to the full power including the accident situation. At the Joyo and Monju, two of Japan's loop-type SFRs, neutron detectors are installed outside the reactor vessel (RV). However, the pool-type SFR must install the neutron detectors inside the RV because the neutron reaching outside the RV is considerably small due to a large RV diameter and a large amount of shielding around the core. The detectors that can withstand the high temperature environment inside the RV is adopted after evaluating the applicability of several types of neutron detectors.