Abstract: A dimensional reactivity management system that takes into account the axial burnup shape data of a nuclear fuel assembly to determine the acceptability of placement of the assembly relative to other assemblies in a storage container.

Abstract: A dimensional reactivity management system that takes into account the axial burnup shape data of a nuclear fuel assembly to determine the acceptability of placement of the assembly relative to other assemblies in a storage container.

Abstract: A change monitoring system for a computer system includes programs for creating and managing a plurality of templates representative of the computer system. A repository stores the templates. A communications network communicates with plural platforms of the computer system. Programs associate the templates with corresponding ones of the platforms and plural software products of the computer system. Other programs monitor the computer system for changes to the platforms or the software products with respect to the templates.

Abstract: A cluster of standardized reduced length burnable absorber rods include a plurality of middle rod sections having a multiplicity of different axial lengths and containing burnable absorber material in sealed chambers therein, a plurality of upper end spacer sections having a multiplicity of different axial lengths and each defining an empty space, and a plurality of lower end spacer sections having a multiplicity of different axial lengths and each defining an empty space. Each of the rods is formed of one middle rod section tandemly arranged between and rigidly interconnecting one upper end spacer section and one lower end spacer section. The three rigidly interconnected sections which form each rod being selected so as to provide the same standard combined axial length for each of the rods in the cluster thereof although the axial lengths of the middle rod sections can vary from rod to rod and thereby the axial location of the burnable absorber material along the rod can also vary from rod to rod.

Abstract: A cluster of standardized reduced length burnable absorber rods include a plurality of middle rod sections having a multiplicity of different axial lengths and containing burnable absorber material in sealed chambers therein, a plurality of upper end spacer sections having a multiplicity of different axial lengths and each defining an empty space, and a plurality of lower end spacer sections having a multiplicity of different axial lengths and each defining an empty space. Each of the rods is formed of one middle rod section tandemly arranged between and interconnecting one upper end spacer section and one lower end spacer section. The three interconnected sections which form each rod being selected so as to provide the same standard combined axial length for each of the rods in the cluster thereof although the axial lengths of the middle rod sections can vary from rod to rod and thereby the axial location of the burnable absorber material along the rod can also vary from rod to rod.

Abstract: A nuclear fuel assembly, particularly advantageous for use in a pressurized water reactor, wherein each alternate fuel rod in the assembly is positioned with its fission gas plenum zone at the top of the assembly and the intervening alternate fuel rods are positioned with their fission gas plenum zones at the bottom of the assembly. All of the fuel rods are preferably axially coextensive. An axial blanket region may be formed by providing the fuel zone of each fuel rod with a small zone of natural or depleted uranium at a part of the fuel zone furthest from the fission gas plenum zone. A method of effectively lengthening the active length of a nuclear fuel assembly is also described.

Abstract: A nuclear fuel assembly for high utilization of the nuclear fuel is disclosed. Alternate fuel rod assemblies are axially shifted relative to each other to create zones of high hydrogen-to-uranium ratios at the ends of the core for high utilization of the fuel at the core ends. Each fuel rod assembly comprises separate upper and lower fuel rods. The axial shift provides intermeshing of the separation between axially aligned fuel rods at the core center. Seed blankets are located at the ends of the core and lower enriched sections are located at the core center during beginning of core life. After a specified amount of fuel depletion from reactor operation, the upper and lower rods are interchanged and an opposite axial shift is employed. The high utilization fuel assembly provides for burnup gradient utilization, axial blanket utilization, plutonium production and burnup, axial power flattening, and less use of enriched uranium.

Abstract: A blanket assembly for a nuclear reactor core perimeter region having at least two regions within the assembly of different H/U ratios and rod enrichments.