Development of in-vessel neutron flux monitor equipped with microfission chambers to withstand the extreme ITER environment

Ishikawa, Masao; Takeda, Keigo; Itami, Kiyoshi

The in-vessel neutron flux monitor equipped with Microfission Chambers (MFCs) has been developed. Since in-vessel components of the MFC are exposed to the extreme ITER environment, such as high radiation, high temperature and high electromagnetic (EM) forces, those components need to withstand such ITER environment. In this study, the in-vessel components of the MFC have been developed in order to apply ITER conditions. For these components, several cases of analyses (neutronic, thermal and EM analysis) and soundness verification tests (high-temperature, vibration and noise immunity test) have been conducted. As a result, it is demonstrated that the in-vessel components of the MFC can be used in the extreme ITER environments for 20 years without any replacements.