Fuel bundles for a nuclear reactor are described and illustrated, and in some cases includes fuel elements each having a first fuel component of recycled uranium, and a second fuel component of at least one of depleted uranium and natural uranium blended with the first fuel component, wherein the blended first and second fuel components have a first fissile content of less than 1.2% wt of .sup.235U. Other fuel bundles are also described and illustrated, and include a first fuel element including recycled uranium, the first fuel element having a first fissile content of no less than 0.72 wt % of .sup.235U; and a second fuel element including at least one of depleted uranium and natural uranium, the second fuel element having a second fissile content of no greater than 0.71 wt % of .sup.235U.

Fuel bundles for a nuclear reactor are described and illustrated, and in some cases includes fuel elements each having a first fuel component of recycled uranium, and a second fuel component of at least one of depleted uranium and natural uranium blended with the first fuel component, wherein the blended first and second fuel components have a first fissile content of less than 1.2% wt of .sup.235U. Other fuel bundles are also described and illustrated, and include a first fuel element including recycled uranium, the first fuel element having a first fissile content of no less than 0.72 wt % of .sup.235U; and a second fuel element including at least one of depleted uranium and natural uranium, the second fuel element having a second fissile content of no greater than 0.71 wt % of .sup.235U.

A basket assembly for receiving a plurality of fuel assemblies includes a basket having a grid defining spacing between fuel assembly compartments, the grid defining a first compartment for receiving a first fuel assembly and a second compartment for receiving a second fuel assembly, wherein the cross-sectional area of the second compartment is larger than the cross-sectional area of the first compartment. The basket assembly is configured to receive in the first compartment a first fuel assembly, the first fuel assembly being a regular fuel assembly, and the basket assembly configured to receive in the second compartment a second fuel assembly, the second fuel assembly being an irregular fuel assembly, wherein the irregular fuel assembly includes at least one irregular fuel rod.

A fuel assembly, which linearizes change of an infinite multiplication factor of a fuel and flattens excess reactivity while increasing average fissile plutonium enrichment of a MOX fuel, and a reactor are provided. The fuel assembly includes first fuel rods containing Pu and not containing burnable poison, a second fuel rod containing uranium and burnable poison and not containing Pu, a water rod, and a channel box accommodating the first and second fuel rods and the water rod in a bundle. The second fuel rod is disposed on an outermost periphery and/or adjacent to the water rod, of a fuel rod array in a horizontal section, and N2<N1 (N2 is a positive integer or zero) is satisfied where the number of second fuel rods arranged on the outermost periphery is N1 and the number of second fuel rods arranged adjacent to the water rod is N2.

A fuel assembly, which linearizes change of an infinite multiplication factor of a fuel and flattens excess reactivity while increasing average fissile plutonium enrichment of a MOX fuel, and a reactor are provided. The fuel assembly includes first fuel rods containing Pu and not containing burnable poison, a second fuel rod containing uranium and burnable poison and not containing Pu, a water rod, and a channel box accommodating the first and second fuel rods and the water rod in a bundle. The second fuel rod is disposed on an outermost periphery and/or adjacent to the water rod, of a fuel rod array in a horizontal section, and N2<N1 (N2 is a positive integer or zero) is satisfied where the number of second fuel rods arranged on the outermost periphery is N1 and the number of second fuel rods arranged adjacent to the water rod is N2.

According to an embodiment, a design method for a light-water reactor fuel assembly comprises: accumulating a determined fuel data, showing that each of a combination of p.Math.n/N and e is feasible as the core or not, wherein N is a number of the fuel rods in the fuel assembly, n is a number of the fuel rods containing the burnable poison, p is a ratio wt % of the burnable poison in the fuel, and e is an enrichment wt % of the uranium 235 contained in the fuel assembly; formulating a criterion formula which determines whether a combination of p.Math.n/N and e is feasible as a core or not and is formulated based on the determined fuel data; and determining whether a temporarily set composition of the fuel assembly is approved as a core or not based on the criterion formula.

The present invention concerns a fuel assembly for a nuclear power boiling water reactor. The fuel assembly comprises fuel rods. At least 95% of the fuel rods comprise nuclear fuel material in the form of U enriched in 235U. At least 20% of the fuel rods belong to a first set of fuel rods. The fuel rods in this first set comprise both U enriched in 235U and Th. The first set comprises a first and a second subset of fuel rods. The ratio, with regard to weight, between Th and U, in each fuel rod of said first subset, is higher than the ratio, with regard to weight, between Th and U, in each fuel rod of said second subset. The invention also concerns a nuclear power boiling water reactor and a manner of operating such a reactor.

The present invention concerns a fuel assembly for a nuclear power boiling water reactor. The fuel assembly comprises fuel rods. At least 95% of the fuel rods comprise nuclear fuel material in the form of U enriched in 235U. At least 20% of the fuel rods belong to a first set of fuel rods. The fuel rods in this first set comprise both U enriched in 235U and Th. The first set comprises a first and a second subset of fuel rods. The ratio, with regard to weight, between Th and U, in each fuel rod of said first subset, is higher than the ratio, with regard to weight, between Th and U, in each fuel rod of said second subset. The invention also concerns a nuclear power boiling water reactor and a manner of operating such a reactor.

A nuclear fuel assembly for a nuclear reactor core including at least one fuel cartridge having a lattice structure including an outer wall defining an interior volume, at least one flow channel extending through the interior volume of the lattice structure, at least one lattice site disposed in the interior of the lattice structure; and at least one fuel compact disposed within a corresponding one of the at least one lattice site. A cross-sectional shape of the at least one fuel compact is the same as a cross-sectional shape of the corresponding one of the at least one lattice site.

A nuclear fuel assembly for a nuclear reactor core including at least one fuel cartridge having a lattice structure including an outer wall defining an interior volume, at least one flow channel extending through the interior volume of the lattice structure, at least one lattice site disposed in the interior of the lattice structure; and at least one fuel compact disposed within a corresponding one of the at least one lattice site. A cross-sectional shape of the at least one fuel compact is the same as a cross-sectional shape of the corresponding one of the at least one lattice site.