[2G10-14] Fuel Debris

[2G12] Modification of STACY for study of criticality characteristics of fuel debris

(8) Design of a two-region core with 400 fuel rods

*Shouhei Araki¹, Satoshi Gunji¹, Kazuhiko Izawa¹, Kenya Suyama¹ (1. Japan Atomic Energy Agency)

Keywords:Fukushima Dai-ichi NPP, modified STACY, Critical Experiment, Fuel Debris

In order to add elasticity to the experimental design of STACY, a two-region core with only 400 existing fuel rods was considered. The two-region core was composed of a test region with 1.27-cm lattice pitch and a driver region with 1.8-cm pitch. It was confirmed that if the test region was larger than 11x11, the neutron flux in the center of the test region could approximately simulate that of a one-region core with a 1.27-cm lattice plate.