| 摘要 |
<p>PROBLEM TO BE SOLVED: To provide a fuel assembly for BWR that can improve the economical efficiency and reactor shutdown margin, and can reduce the reactivity and local peaking factor at a low temperature in an axially upper region.SOLUTION: In the fuel assembly for BWR of the present invention, a set of fuel rods formed by filling fuel pellets containing fuel material into cladding tubes is arranged in a square lattice arrangement of 10 or more rows and 10 or more columns, and water rods are disposed in the regions corresponding to a plurality of fuel rods. The set of fuel rods includes first fuel rods (standard fuel rods), second fuel rods (enrichment division fuel rods) in which the enrichment of the axially lower part is higher than that of the axially upper part, and third fuel rods (partial length fuel rod) having a relatively short fuel effective length. The second fuel rods are arranged only at positions on the outermost periphery of the fuel assembly and/or positions adjacent to the water rods.</p> |
