Validation study on SFR core bowing codes using Joyo ex-core experiment data; Single duct bowing benchmark

Ohgama, Kazuya   ; Doda, Norihiro  ; Ota, Hirokazu*; Wozniak, N.*; Uwaba, Tomoyuki ; Futagami, Satoshi  ; Tanaka, Masaaki  ; Yamano, Hidemasa   ; Ogata, Takanari*; Shemon, E.*; Feng, B.*

To enhance the accuracy of the safety evaluations for sodium-cooled fast reactors, it is necessary to develop a method that can realistically evaluate the reactivity changes induced by core deformation. In this context, Japan and the United States jointly conducted a benchmark analysis of thermal bowing experiments using a single duct from a Joyo-type fuel assembly. The aim was to confirm the validity of the core bowing analysis codes. Comparisons of analysis and experimental results demonstrated that the codes used by both countries were able to reasonably predict the axial distribution of horizontal duct displacement caused by thermal bowing as well as the contact load on the duct pad.