Abstract: According to at least some example embodiments, a dome collector separation stage includes an inner side wall that defines an inner channel; and an outer side wall that, together with the inner side wall, defines an outer channel, the inner channel being configured to receive a two-phase flow stream (FS) of water and steam, and pass the two-phase FS to the outer channel via inlets included in the inner side wall, the outer channel being configured to separate at least some water from the two-phase FS, and pass moisture-reduced steam out of the steam separator stage via outlets included in the outer side wall.

Abstract: The disclosure relates to a device for checking a fuel rod comprising a testing container having first and second chambers, a first checking device arranged in the testing container, wherein the testing container has at least one inlet opening, at least one outlet opening, and an insertion opening for inserting the fuel rod into the second chamber, and wherein a valve is arranged in a connecting channel connecting the first and the second chamber. A method is disclosed for checking a fuel rod in a water-filled basin of a submerged nuclear plant having such a device, wherein the fuel rod is inserted into the second chamber of the testing container through the insertion opening while the valve is closed, wherein a fluid is fed in via the at least one inlet opening, and wherein the valve is opened in order to check the fuel rod with the first checking device.

Abstract: An irradiation target processing system for insertion and retrieving irradiation targets into and from an instrumentation tube in a nuclear reactor core comprises, a target retrieving system, target insertion system and transport gas supply system, mounted on a movable support, wherein: the target retrieving system comprises a target exit port coupled to a target storage container and exhaust system; the target insertion system comprises a target filling device, target retention tubing with target supply junction connectable to the instrumentation tube, and a target diverter coupled to the target filling device, target retention tubing and target retrieving system; and the transport gas supply system comprises a first gas supply tubing coupled to the exit port of the target retrieving system, a second gas supply tubing coupled to a junction for supplying gas to the instrumentation tube, and a transport gas supply junction coupled to the first and second gas supply tubing.

Abstract: A method and apparatus for extending the period a nuclear steam supply system spent fuel pool can be safely passively cooled by storing the spent fuel offloaded from the reactor, in the containment for one reactor operating cycle. During a refueling the spent fuel that is not to be returned to the reactor and the spent fuel that will be returned to the reactor are stored separately in shielded locations within the containment. After one operating cycle, the spent fuel stored within the containment that was not returned to the reactor just prior to the last operating cycle, is offloaded to the spent fuel pool and replaced by the newly offloaded spent fuel that is being retired.

Abstract: Disclosed is a method for managing stoppage of a pressurized-water nuclear reactor integrated into a submerged module for producing electrical power, in case of detection of a primary/secondary leak in a steam generator equipped with a safety valve, which generator is connected to the reactor and associated with a standby cooling unit. The method includes: detecting a primary/secondary leak in the steam generator; automatically stopping the reactor and isolating the broken steam generator; bringing the corresponding standby cooling unit online; monitoring the primary pressure and, once the primary pressure has passed below the set pressure of the safety valves of the steam generators, isolating the standby cooling unit of the broken steam generator; and continuing to passively cool the reactor with the remaining steam generators and cooling unit.

Abstract: A method, system and computer program product for measuring a spatial displacement of at least a part of an irradiating nuclear fuel assembly. The system comprising a memory and a processor configured to receive data from said memory. The processor and the computer program being configured to: receive a first image data frame, captured using an imaging system, said first image data frame comprising information representing a first view of an observed real world scene comprising at least a part of a fuel assembly, wherein said first image data frame is captured from a first direction; generate a set of reference coordinates, corresponding to image coordinates of said first image data frame; and extract measurement data indicative of a spatial displacement relating to at least a part of said fuel assembly, based on information from said first image data frame and information from said set of reference coordinates.

Abstract: A nuclear reactor includes a passive reactivity control nuclear fuel device located in a nuclear reactor core. The passive reactivity control nuclear fuel device includes a multiple-walled fuel chamber having an outer wall chamber and an inner wall chamber contained within the outer wall chamber. The inner wall chamber is positioned within the outer wall chamber to hold nuclear fuel in a molten fuel state within a high neutron importance region. The inner wall chamber allows at least a portion of the nuclear fuel to move in a molten fuel state to a lower neutron importance region while the molten nuclear fuel remains within the inner wall chamber as the temperature of the nuclear fuel satisfies a negative reactivity feedback expansion temperature condition. A duct contains the multiple-walled fuel chamber and flows a heat conducting fluid through the duct and in thermal communication with the outer wall chamber.

Abstract: According to an embodiment, a core catcher has: a main body including: a distributor arranged on a part of a base mat in the lower dry well, a basin arranged on the distributor, cooling channels arranged on a lower surface of the basin connected to the distributor and extending in radial directions, and a riser connected to the cooling channels and extending upward; a lid connected to an upper end of the riser and covering the main body; a cooling water injection pipe open, at one end, to the suppression pool, connected at another end to the distributor; and chimney pipes connected, at one end, to the riser, another end being located above the upper end of the riser and submerged and open in the pool water.

Abstract: A Gland Seal End Plug closure for a nuclear fuel rod cladding composed of silicon carbide or other materials that cannot be welded. The sealant is, preferably, made from one or more forms of pure graphite and the ram, seat and other components of the Gland Seal End Plug are formed from high temperature metallic or ceramic materials.

Abstract: In various embodiments, a method of processing one or more semiconductor wafers is provided. The method includes positioning the one or more semiconductor wafers in an irradiation chamber, generating a neutron flux in a spallation chamber coupled to the irradiation chamber, moderating the neutron flux to produce a thermal neutron flux, and exposing the one or more semiconductor wafers to the thermal neutron flux to thereby induce the creation of dopant atoms in the one or more semiconductor wafers.

Abstract: Design and making methods of a neutrons generating target are described. In some embodiments, a surface of a target substrate can be modified to form one or more surface features. In some embodiments, a neutron source layer can be disposed on the surface of the target substrate. In some embodiments, the neutron source layer and the target substrate can be heated to an elevated temperature to form a bond between the two. In some embodiments, the surface modification of the target substrate can reduce blistering and material exfoliation in the target. The target can be used in boron neutron capture therapy.

Abstract: A nuclear reactor containment system including a nuclear reactor and a container enclosing the nuclear reactor. The container includes a number of heat removal systems each having an active state and an inactive state, wherein the heat removal systems dissipate heat from the container more efficiently in the active state than in the inactive state, and wherein the heat removal systems are structured to switch from the inactive state to the active state based on a temperature of the container.

Abstract: An apparatus, system and method for handling and translating high level radioactive waste. The apparatus comprises a body for supporting the cask close to the ground so that the cask and the apparatus can pass underneath over head doors. The apparatus further comprises rollers for translating the cask. The apparatus additionally supports the storage cask during spent nuclear fuel transfer procedures.

Abstract: Non-intrusive error detection techniques for control and shutdown rod position in nuclear reactors, including methods of monitoring digital rod position indication (DRPI) signals of a DRPI system of a nuclear power plant. The methods include acquiring digital rod position signals at a point between a DRPI display cabinet and a DRPI data cabinet of the DRPI system, and processing the digital rod position signals to identify variations in a signal level and a signal timing of the digital rod position signals to determine rod position errors of the DRPI system.

Abstract: Methods implemented by at least one electronic processor for generating pointwise fast neutron spectra may include receiving composition data; receiving source data or calculating the source data; receiving nuclear data; and calculating the pointwise fast neutron spectrum based on numerical integration using the composition, source, and nuclear data. Systems for generating pointwise fast neutron spectra may include a bus; at least one electronic processor connected to the bus; an input device connected to the bus; and a communication link connected to the bus. The at least one electronic processor may be configured to receive composition data from the input device via the bus, to receive source data from the input device via the bus or to calculate the source data, to receive nuclear data from the communication link via the bus, and to calculate the pointwise fast neutron spectrum based on numerical integration using the composition, source, and nuclear data.

Abstract: A self-powered integral in-core instrument thimble assembly for monitoring the temperature and radiation levels surrounding a nuclear fuel assembly, that transmits output signals wirelessly to a remote location. The in-core instrument thimble assembly is activated by a short exposure within a reactor core and remains active after the fuel assembly is removed from the reactor core to continuously provide a remote monitoring capability for the fuel assembly as it is transported or stored at a remote location, without an external power source.

Abstract: An accelerator neutron source (ANS) including a field ionization (FI) array configured to generate deuterium and tritium ions and a plasma for containing the deuterium and tritium ions produced by the FI array. The ANS also includes a target comprising deuterium and tritium ions and the ANS is configured to accelerate deuterium and tritium ions produced by the FI array toward the target to generate neutrons by applying a voltage to an accelerating electrode.

Abstract: A neutron absorber apparatus for use in restoring reactivity control to a nuclear fuel rack. The apparatus comprises an elongated tubular insert assembly configured for insertion in a storage cell of the rack. First and second absorber plates, each formed of a boron-containing material, are coupled together by upper and lower stiffening bands at the insert extremities and form a longitudinally-extending cavity configured for receiving a fuel assembly. The absorber plates and stiffening bands may have a rectilinear cross sectional configuration in one embodiment. At least one elastically deformable locking protrusion mounted proximate to the lower end of the absorber plates lockingly engages an available lower edge disposed in the cell sidewall above its bottom end. This fixes the tubular insert axially in the cell, thereby preventing its withdrawal after installing the insert. In one embodiment, the edge may be the bottom of existing absorber sheathing in the cell.

Abstract: A container for storing and/or transporting spent nuclear fuel. The container includes a body that defines an internal cavity that holds the spent nuclear fuel and an outer surface. The outer surface has holes formed therein into which trunnions are positioned. The container can be lifted by a lift yoke by coupling the lift yoke to the trunnions. The trunnions may include first and second components such that the first component is slidable in its axial direction relative to the second component when a force that exceeds a threshold acts on the second component. Thus, the second component may be slidable between a protruded state in which a portion of the second component protrudes from the outer surface of the body and a retracted state in which the second component does not protrude from the outer surface of the body.

Abstract: A plasma containment system comprises a chamber, a magnetic field generator, and an annular plasma layer that comprises a circulating beam of ions. The chamber includes axial insulating breaks in the chamber wall that run along almost the entire length of the chamber. An inductive plasma source is mountable within the chamber and includes a shock coil assembly and a Laval nozzle to introduce gas into the inductive plasma source. A RF drive comprises a quadrupolar cyclotron located within the chamber and having four azimuthally symmetrical electrodes with gaps there between.