FAST REACTOR FUEL ASSEMBLY AND FAST REACTOR CORE

• Main Authors: YAMAOKA MITSUAKI, MORIKI YASUYUKI
• Format: Patent
• Language: English; Japanese
• Published: 18.01.2016
• Subjects: NUCLEAR ENGINEERING; NUCLEAR PHYSICS; NUCLEAR REACTORS; PHYSICS

PROBLEM TO BE SOLVED: To provide a fast reactor fuel assembly capable of suppressing an increase in sodium void reactivity while keeping an MA burning rate high.SOLUTION: A fast reactor fuel assembly comprises: a cylindrical duct tube 14; a partition wall 13 separating a space within the duct tube 14 into a central region 10a and an annular region 10b; a plurality of first fuel rods 11 each containing a mixture of minor actinide and a medium substance in a cylindrical first cladding tube having closed both ends and extending in a longitudinal direction, the first fuel rods 11 being disposed in the central region 10a in parallel; and a second fuel rods 12 each containing a mixture of plutonium and uranium in a cylindrical second cladding tube having closed both ends and extending in the longitudinal direction, the second fuel rods 12 being disposed in the annular region 10b in parallel. During normal operation, a ratio of an output from the first fuel rods 11 in the central region 10a to a flow volume of the central region 10a is set higher than a ratio of an output from the second fuel rods 12 in the annular region 10b to a flow volume of the annular region 10b. 【課題】ＭＡ燃焼率を高く保ちながら、ナトリウムボイド反応度の増大を抑制する高速炉用燃料集合体を提供する。【解決手段】高速炉用燃料集合体は、ラッパ管１４と、ラッパ管１４内の空間を中心領域１０ａと環状領域１０ｂとに分割する隔壁１３と、両端が閉止され長手方向に延びる筒状の第１被覆管にマイナーアクチニドおよび媒体物質の混合物を内包し、それぞれ中心領域に互いに並列に配される複数の第１燃料棒１１と、両端が閉止され長手方向に延びる筒状の第２被覆管にプルトニウムおよびウランの混合物を内包し、それぞれ前記環状領域に互いに並列に配される複数の第２燃料棒１２を有する。通常運転時において、中心領域１０ａ内の複数の第１燃料棒１１の出力の中心領域１０ａの流量に対する比が、環状領域１０ｂ内の複数の第２燃料棒１２の出力の環状領域１０ｂの流量に対する比よりも大きくなるように形成されている。【選択図】図１