2023 Annual Meeting

Presentation information

Oral presentation

III. Fission Energy Engineering » 301-1 Reactor Physics, Utilization of Nuclear Data, Criticality Safety

[3K01-05] Criticality Analysis of Fuel Debris 1

Wed. Mar 15, 2023 9:30 AM - 10:55 AM Room K (13 Bildg.2F 1322)

Chair:Yasushi Nauchi(CRIEPI)

9:45 AM - 10:00 AM

[3K02] Study on the criticality monitoring method by measurements of short-half-life noble-gas fission products for the criticality monitoring of fuel debris inside a primary containment vessel of Fukushima Daiichi Nuclear Power Stations

*Eka Sapta Riyana1, Masahiro Sakamoto1, Taichi Matsumura1, Kenichi Terashima1, Keisuke Okumura1 (1. JAEA)

Keywords:Fuel Debris, Subcritical System, Neutron Multiplication Factor, Monte Carlo Calculation, Short Half-life Fission Products

We investigated the possibility of estimating the effective neutron multiplication factor (keff) of the fuel-debris inside the primary containment vessel (PCV) of unit-2 of Fukushima Daiichi Nuclear Power Station (1F) using remote gas-radioactivity measurement. Our calculation result demonstrates the correlation between keff and the activity ratio (AR) of 88Kr-to-135Xe for various fuel debris compositions and geometry. We also show the time-dependent behavior of the AR of 88Kr-to-135Xe when the keff changes suddenly in PCV.