Abstract: A method for producing uniform activity targets according to an embodiment of the invention may include arranging a plurality of targets in a holding device having an array of compartments, each target being assigned to a compartment based on a known flux of a reactor core so as to facilitate an appropriate exposure of the targets to the flux based on target placement within the array of compartments. The holding device may be positioned within the reactor core to irradiate the targets. The method may be used to produce brachytherapy and/or radiography targets (e.g., seeds, wafers) in a reactor core such that the targets have relatively uniform activity.

Abstract: A fuel assembly of a boiling water reactor contains a fuel assembly base closed at the top by a filter plate, a fuel assembly head, and, disposed between them, a bundle of long and medium-length fuel rods extending away from the fuel assembly base. A water channel is disposed inside the fuel rod bundle. A plurality of the medium-length fuel rods are fixed axially on a separate holding part which is connected to the upper side of the fuel assembly base.

Abstract: A compressor assembly and the method of using the same which includes an elongated spiral passageway within which a compact toroid plasma, such as a compact toroid plasma structure, can be efficiently compressed to a high-energy state by compressing the compact toroid plasma structure by its own momentum against the wall of the spiral passageway in a manner to induce heating by conservation of energy. The compressor assembly also includes a burn chamber that is in communication with the spiral passageway and into which the compressed compact toroid plasma structure is introduced following its compression.

Abstract: Disclosed is a fuel rod testing apparatus for a nuclear fuel assembly. The fuel rod testing apparatus includes a helium leakage testing chamber having a gate so that a fuel rod is horizontally loaded/unloaded and testing whether or not helium leaks from the fuel rod, a fuel rod upward/downward transfer unit that has first and second transfer sections located in front of the gate and horizontally installed apart from each other in order to guide the fuel rod loaded into or unloaded from the helium leakage testing chamber, and that vertically drives the first and second transfer sections, and a main frame that has a upper transfer section disposed in parallel in a lengthwise direction of the fuel rod upward/downward transfer unit and having an inclined face and a lower transfer section installed at a lower portion of the upper transfer section and having an inclined face.

Abstract: Short pulse neutron generators are described herein. In a general embodiment, the short pulse neutron generator includes a Blumlein structure. The Blumlein structure includes a first conductive plate, a second conductive plate, a third conductive plate, at least one of an inductor or a resistor, a switch, and a dielectric material. The first conductive plate is positioned relative to the second conductive plate such that a gap separates these plates. A vacuum chamber is positioned in the gap, and an ion source is positioned to emit ions in the vacuum chamber. The third conductive plate is electrically grounded, and the switch is operable to electrically connect and disconnect the second conductive plate and the third conductive plate. The at least one of the resistor or the inductor is coupled to the first conductive plate and the second conductive plate.

Abstract: An improved fusion reactor design with provision for supplying plasma fuel inside a model reactor without consuming additional power in the process. Embodiments provide free choice of useful fuels from the full range of fusible isotopes. Other embodiments provide means of selectively extracting up-scattered electrons from the plasma, followed by replacing them with electrons of corrected energy. Computer simulations show fusion reactors constructed with these inventive improvements will demonstrate increased net-power compared to other fusion reactors of similar size. The Specification of the invention leads immediately to staged reactor development, starting from small-scale model-reactors, moving on to larger and larger scale models, culminating with commercial power plants.

Abstract: An inspection apparatus for a penetration pipe of a nuclear reactor head comprising: a body; a probe module installed at the body and having a probe which is inserted in the penetration pipe to inspect damage of the penetration pipe; a fixing module installed along a longitudinal direction of the body and having an expanding cylinder which is inserted in the penetration pipe to support an inner diameter of the penetration pipe; and a rotating module installed in the longitudinal direction of the body and having an expanding cylinder which is inserted in the penetration pipe to support the inner diameter of the penetration pipe.

Abstract: A capsule for holding, irradiating, and eluting a material is provided. Methods of fabricating and using the capsule are also provided. The capsule may include a multidiameter tube with a first end region, a second end region, and a middle region. Washers and filters are provided in the end regions and the end regions may be sealed using various methods and materials with the end caps press fit into the end regions. The middle region is designed to store a material to be irradiated by a neutron flux source. The capsule components may be made from materials having a low nuclear cross section so that the capsule may be handled safely after an irradiation step is performed. The capsule is also designed to have a symmetric configuration as an elution and irradiation column so that the same capsule may be used to elute the material within the middle region of the capsule after an irradiation step is performed.

Abstract: The disclosed embodiments relate to ion delivery mechanisms, e.g., for fusion power. Particularly, some embodiments relate to systems and methods for delivering ions to a fuel source in such a manner to initiate fast ignition. The ions may be accumulated into “microbunches” and delivered to the fuel with considerable energy and velocity. The impact may compress the fuel while delivering sufficient energy to begin the fusion reaction.

Abstract: A control rod guide frame comprises a self supporting stack of two or more columnar elements defining a central passage. The columnar elements may include mating features that mate at abutments between adjacent columnar elements of the stack. The control rod guide frame is suitably used in conjunction with a control rod drive mechanism (CRDM) operatively connected with at least one control rod, and a nuclear reactor core, in which the CRDM moves the at least one control rod into and out of the nuclear reactor core under guidance of the control rod guide frame. In another embodiment, a control rod guide frame comprises a stack of two or more columnar elements defining a central passage having a constant cross-section as a function of position along the central passage. In another embodiment, a control rod guide frame comprises an extruded columnar element providing continuous control rod guidance.

Abstract: A core catcher includes a holding surface that catches and holds corium and that introduces a surrounding coolant into the core catcher and cool the core catcher by heat exchange with the introduced coolant. The holding surface and the cooling unit are constructed by arranging blocks which each include a polyhedron having at least one pair of parallel surfaces and having an opening portion formed in a surface located in a lateral direction when a first surface that is one of the parallel surfaces is arranged as a bottom surface and are configured such that the polyhedrons communicate with each other via the opening portion when the polyhedrons are arranged adjacent in the lateral direction. The core catcher can achieve easier installation of the blocks without an increase in installation cost.

Abstract: A spacer grid includes intersecting straps defining cells with springs and dimples arranged to hold fuel rods passing through the cells. The direction of the springs switches at a switch point in the spacer grid that is not at the center of the spacer grid. The intersecting straps may include a first set of mutually parallel straps including a first transition strap and a second set of mutually parallel straps including a second transition strap, with the second set intersecting the first set. The springs of the first set of mutually parallel straps face away from the first transition strap, and the springs of the second set of mutually parallel straps face away from the second transition strap. The outer straps in some embodiments include dimples but not springs.

Abstract: Systems, devices, and methods for determining and applying true time delay (TTD) values for compensating for free-space path length differences between a phased array and a reflector in wideband communication are disclosed. TTD values are determined for individual and groups of antenna elements in phased array fed reflector (PAFR) antennas based distances from a focal region of the reflector. The distance from the focal region of the reflector and the offset of the phased array from the reflectors focal plane can be used to determine path length differences. Corresponding TTD values for antenna elements are then determined based on the path length difference associated with the antenna elements. Each antenna element can be coupled to a TTD element to provide the corresponding TTD value to the signals received by and generated by the antenna elements of the phased array. The TTD elements include transverse electromagnetic (TEM) mode mechanisms.

Abstract: A telescoping guide for extraction and reinsertion support handling of in-core instrument thimble assemblies in the area above the upper support plate in the upper internals of a pressurized water reactor. The telescoping guides extend between the upper ends of the upper internals support columns and an axially movable instrumentation grid assembly which is operable to simultaneously raise the telescoping guides and extract the in-core instrument thimble assemblies from the reactor fuel assemblies.

Abstract: A system and method for containing plasma and forming a Field Reversed Configuration (FRC) magnetic topology are described in which plasma ions are contained magnetically in stable, non-adiabatic orbits in the FRC. Further, the electrons are contained electrostatically in a deep energy well, created by tuning an externally applied magnetic field. The simultaneous electrostatic confinement of electrons and magnetic confinement of ions avoids anomalous transport and facilitates classical containment of both electrons and ions. In this configuration, ions and electrons may have adequate density and temperature so that upon collisions they are fused together by nuclear force, thus releasing fusion energy. Moreover, the fusion fuel plasmas that can be used with the present confinement system and method are not limited to neutronic fuels only, but also advantageously include advanced fuels.

Abstract: The ex-core nuclear instrumentation system includes a key hole, and it is configured such that in the state where a key lock switch is inserted into the key hole, writing to a electrically rewritable nonvolatile memory is made valid by a general-purpose logic, and when writing to a electrically rewritable nonvolatile memory is in valid and the operation panel and the FPGA perform a serial communication and in a case where the data order of the serial communication is the predetermined data order, the CPU controls the electrically rewritable nonvolatile memory, and rewriting data, which is outputted from the operation panel, to the electrically rewritable nonvolatile memory is transmitted from the FPGA to the electrically rewritable nonvolatile memory so as to rewrite the data in the electrically rewritable nonvolatile memory.

Abstract: An isotope production target rod for a power generating nuclear reactor is provided. The isotope production target rod can include at least one rod central body including an outer shell that defines an internal cavity and a plurality of irradiation targets within the internal cavity. The irradiation targets can be positioned in a spatial arrangement utilizing a low nuclear cross-section separating medium to maintain the spatial arrangement.

Abstract: A 17×17 jacketless fuel assembly for a PWR-type light-water reactor uses thorium as the fuel. The fuel assembly has a square shape in the plan view, a seed region, a blanket region that encircles it, an upper nozzle, and a lower nozzle. The fuel elements of the seed region re arranged in the rows and columns of a square coordinate grid and have a four-lobed profile that forms spiral spacer ribs along the length of a fuel element. The blanket region contains a frame structure within which a bundle of fuel elements made from thorium with the addition of enriched uranium is positioned. The blanket region fuel elements are arranged in the two or three rows and columns of a square coordinate grid.

Abstract: A concrete storage module (26) is adapted to slideably receive a cylindrical canister assembly (12) therein. Heat dissipation fins (62) and a tubular heat shield (96) are disposed within the module to help dissipate heat emitted from the nuclear fuel assemblies stored in the canister to air flowing through the module. The canister assembly (12) is composed of a basket assembly (70) constructed from multi-layer structural plates disposed in cross-cross or egg carton configuration. A single port tool (106) is provided for draining water from the canister (12) and replacing the drain water with make-up gas. The single port tool is mounted in the cover (100) of the canister and is in fluid flow communication with the interior of the canister.

Abstract: A high-temperature gas reactor control rod is provided that does not degrade the joining state between the control rod elements even when stress is applied thereto, and that can improve the safety of the high temperature gas reactor remarkably by improving the heat resistance thereof. The high-temperature gas reactor control rod has a plurality of control rod elements (1) each having a neutron absorber (7) between an outer cylinder (9) and an inner cylinder (8) that form a double cylindrical tubular shape, the control rod elements (1) joined to each other in a vertical direction, characterized by: a columnar support member (2) for supporting at least the neutron absorber (7), disposed in the inner cylinder (8); and joining means for joining to another control rod element (1), provided at least one of upper and lower ends of the support member (2).