X線イメージングを用いた球充填層内のボイド率分布計測

Measurement of void fraction distribution in a sphere-packed bed using X-ray imaging

山本 誠士郎*; 大平 直也*; 伊藤 大介*; 伊藤 啓*; 齊藤 泰司*; 今泉 悠也 ; 松場 賢一  ; 神山 健司  

Yamamoto, Seishiro*; Odaira, Naoya*; Ito, Daisuke*; Ito, Kei*; Saito, Yasushi*; Imaizumi, Yuya; Matsuba, Kenichi; Kamiyama, Kenji

In the safety study on a sodium-cooled fast reactor, it is assumed that the high temperature fuel debris are formed because of a core disruptive accident. During the cooling of the fuel debris, gas-liquid two-phase flow can be generated in the debris due to the coolant boiling. To improve the prediction accuracy of the flow characteristics, detailed measurement of the gas-liquid two-phase flow in the debris bed is required. In this study, gas-liquid two-phase flow in a quasi-two-dimensional sphere-packed bed, which simulates the debris bed, is visualized by using X-ray imaging. The experimental results show that the local void fraction increases near the splitting section in the packed bed and decreases near the coalescence section.