Abstract: Embodiments of the invention are directed to a method for production of a nuclear fuel pellet by spark plasma sintering (SPS), wherein a fuel pellet with more than 80% TD or more than 90% TD is formed. The SPS can be performed with the imposition of a controlled uniaxial pressure applied at the maximum temperature of the processing to achieve a very high density, in excess of 95% TD, at temperatures of 850 to 1600° C. The formation of a fuel pellet can be carried out in one hour or less. In an embodiment of the invention, a nuclear fuel pellet comprises UO2 and a highly thermally conductive material, such as SiC or diamond.

Abstract: A nuclear reactor cooling system includes a cooling water tank disposed above a containment; a spray header connected to the cooling water tank through a first communicating pipe; and an air tank disposed inside the containment; wherein the spray header is disposed outside the containment and used for spraying cooling water to the outer wall of the containment; the cooling water tank is a closed container, and the air tank is connected to the top portion of the cooling water tank through a second communicating pipe. The nuclear reactor cooling system has higher reliability in cooling containment.

Abstract: A containment cooling apparatus includes a cooling water tank disposed above a containment; a spray header connected to the cooling water tank via a first communicating pipe, wherein the spray header is disposed on an outside of the containment for spraying cooling water to an outer wall of the containment; a bell shaped shield covering the containment, wherein the cooling water tank is disposed on a top portion of the shield; a space formed between an inner wall of the shield and the outer wall of the containment, wherein the spray header is disposed in the space; an exhaust hole disposed on the top portion of the shield; and a water separator disposed in the exhaust hole and/or the space. The containment cooling apparatus has higher utilization of coolant.

Abstract: A containment cooling system capable of improving coolant utilization rate comprises a cooling water tank disposed above the containment, a spray header connected to the cooling water tank by a first communicating pipe, a bell-shaped shield, and a clearance, wherein the cooling water tank is disposed on top of the shield, and the spray header is located in the clearance; cooling fins are disposed in the clearance, wherein a flow passage is disposed between the cooling fins and the outer wall of the containment. The containment cooling system has a higher coolant utilization rate.

Abstract: A method of preparing a surface includes applying rough material layer to a surface of a support material. The rough material layer has a thickness in a range of 50 nm to 5 micrometers and a roughness Ra in a range of 10 nm to 1 micrometer. The method includes depositing a ceramic nitride or oxynitride over the rough material layer. In an example, a vehicle includes a structural support and a component comprising a support material defining an exterior facing surface and a ceramic nitride or oxynitride layer disposed over the support material.

Abstract: A Thorium fuel rod assembly is disclosed that includes first and second support elements and a number of Thorium fuel rods positioned between support elements. Each of the Thorium fuel rod includes an outer fuel element containing a solid Thorium an inner core element containing Beryllium that is positioned within an interior cavity defined by the outer fuel element. In an exemplary disclosure, the inner core element also defines an inner cavity such that a beam of high energy particles may be directed into the inner cavity of the inner core element to impinge upon a Beryllium nucleus within the inner core element to produce a (p, n) reaction resulting in the emission of a neutron, where the emitted neutron may interact with a Thorium nucleus in the outer fuel element to cause the Thorium nucleus to fission.

Abstract: A pump leakage mitigation device includes one or more clamp arms on an outer surface of a pump that can be driven by a biasing element to seat against a shaft of the pump to seal or reduce fluid flow through a breakdown of the pump. The biasing element engages only at threshold temperatures, such as those associated with breakdown orifice failure when additional sealing may be necessary. Clamp arms of any number and shape can be used to achieve the desired seal and based on the pump geometry. A sealant surface and/or keeping mechanism are useable with the leakage mitigation device to enhance fluid flow blockage throughout a pump failure transient scenario. Pump leakage mitigation devices are installed on an outside of a variety of different pump types and can thus be installed, actuated, manipulated, disengaged, and/or removed without having to destroy or disassemble the pump.

Abstract: A nuclear fuel storage cask includes an outer shell having a length extending from a first end to a second end of the outer shell, the outer shell defining an inner cavity circumscribed by the outer shell, an outer perimeter extending around the outer shell, an inner perimeter positioned inward from the outer perimeter, and a cooling circuit extending along the length of the outer shell, the cooling circuit including an inner passage, and an outer passage, a coolant positioned within the cooling circuit, where the coolant is configured to move through the inner passage, absorbing heat from the inner cavity of the outer shell, and the coolant is configured to move through the outer passage, dissipating heat through the outer perimeter of the outer shell, and a lid coupled the outer shell, where the lid covers the inner cavity of the outer shell.

Abstract: Control rod drives include linearly-moveable control elements inside an isolation barrier. Control rod drives move the control element through a motor and rotor powering a linear screw internal to an isolation barrier. Induction coils may generate magnetic fields and be moveable across a full stroke length of the control element in the reactor. The magnetic fields hold closed a releasable latch to disconnect the control elements from the linear drives. A control rod assembly may join to the control element. The control rod assembly may lock with magnetic overtravel latches inside the isolation barrier to maintain an overtravel position. Overtravel release coils outside the isolation barrier may release the latches to leave the overtravel position. Operation includes moving the magnetic fields and releasable latch together on opposite sides of an isolation barrier to drive the control element to desired insertion points, including full insertion by gravity following de-energization.

Abstract: A controlled fusion process is provided that can produce a sustained series of fusion reactions: a process that (i) uses a substantially higher reactant density of the deuterium and tritium gases by converging cationic reactants into the higher reaction density at a target cathode rather than relying on random collisions, the converging producing a substantially higher rate of fusion and energy production; (ii) uses a substantially lower input of energy to initiate the fusion; (iii) can be cycled at a substantially higher cycle frequency; (iv) has a practical heat exchange method; (v) is substantially less costly to manufacture, operate, and maintain; and, (vi) has a substantially improved reaction efficiency as a result of not mixing reactants with products.

Abstract: A catalytic recombiner and filter apparatus is especially suited for placement in a containment of a nuclear reactor. The apparatus has a natural convection flow duct with a number of catalytic elements for recombining hydrogen and oxygen contained in a gas flow through the flow duct. The catalytic recombiner and filter apparatus provides for reliable hydrogen reduction and iodine filtering for a gas flow even for a comparatively long period of operation. The catalytic recombiner and filter apparatus includes a number of adsorber elements with iodine adsorbing surfaces and with macroscopic flow channels in between. The iodine adsorbing surfaces are flown over by the gas flow, and the adsorber elements are arranged, when in use, downstream of the catalytic elements in a direction of the gas flow.

Abstract: A fuel assembly design for nuclear reactors that is used in fast neutron reactor cores to provide more reliable spacing of a fuel element bundle in a fuel assembly and reduced local stress in the cladding of the fuel elements in the region where the elements are in contact with spacing elements. The fuel assembly has a top nozzle and a bottom nozzle which are connected to one another by a jacket. A bundle of rod-type fuel is elements arranged in the fuel assembly with the aid of a grid and spiral spacer elements wrapped around the cladding of each fuel element. At least the peripheral fuel elements in the bundle are provided with spacer elements in the form of thin-walled tubes with longitudinal through slots, wherein the elements have a substantially oval cross section in the regions where they are in contact with the jacket.

Abstract: An apparatus for performing an inspection on the beams of the top guide of a BWR includes a housing, an alignment assembly, and an inspection system. The housing is receivable atop the upper edges of a first pair of beams adjacent a receptacle of the top guide. The reception of the housing atop the upper edges of the first pair of beams is facilitated by the alignment assembly which includes a plurality of legs that are simultaneously moved between a retracted position wherein one or more of the legs is disengaged from the beams within the receptacle and an extended position wherein all of the legs are engaged with the beams of the top guide within the receptacle. The inspection system includes a pair of inspection elements that are translated above a second pair of beams that are adjacent the receptacle and that do not have the housing received thereon.

Abstract: A passive safety and cooling system for nuclear fission reactors powered by a bundle of radioactive fuel rods enclosed in a pressure vessel provides four redundant levels of dissipating and containing heat. Metal layered with carbon nanotube surrounds the pressure vessel, lines the system's floor, and studs a concrete containment dome. A retractable ceramic tile outer dome contains, absorbs and blocks any remaining heat or nuclear reactions, and optionally, releases them to the atmosphere, for the ultimate dissipation.

Abstract: Configurations of molten fuel salt reactors are described that include an auxiliary cooling system which shared part of the primary coolant loop but allows for passive cooling of decay heat from the reactor. Furthermore, different pump configurations for circulating molten fuel through the reactor core and one or more in vessel heat exchangers are described.

Abstract: A method, system, and apparatus are disclosed for a complex shape structure for liquid lithium first walls of fusion power reactor environments. In particular, the method involves installing at least one tile on the surface area of the internal walls of the reactor chamber. The tile(s) is manufactured from a high-temperature resistant, porous open-cell material. The method further involves flowing liquid lithium into the tile(s). Further, the method involves circulating the liquid lithium throughout the interior network of the tile(s) to allow for the liquid lithium to reach the external surface of the tile(s) that faces the interior of the reactor chamber. In addition, the method involves outputting the circulated liquid lithium from the tile(s). In one or more embodiments, the reactor chamber is employed in a fusion reactor. In some embodiments, the tile is manufactured from a ceramic material or a metallic foam.

Abstract: When a power source is lost after an operation stop of a nuclear power plant, a first open/close valve is opened via a first battery at an early stage and steam in a reactor pressure vessel (RPV) is condensed in a suppression pool. The heat of the water in the suppression pool is transmitted to a cooling water pool located below inner space between first and second reactor containment vessels surrounding the RPV. A second open/close valve is opened via a second battery at the early stage and cooling water in a tank is injected into the RPV. After the early stage, a third open/close valve is opened via a third battery, and a cooling medium becomes steam by an evaporator in the RPV, the steam being condensed by a condenser disposed in the inner space to become a liquid of the cooling medium and is returned to the evaporator.

Abstract: A method and apparatus for modifying an existing nuclear reactor moveable in-core detector system to insert and withdraw target specimens from a reactor core during reactor operation without practically impeding the moveable in-core detector system's ability to obtain flux maps of the core throughout the reactor's operation. The apparatus provides a separate drive unit and delivery cable that is independent of the detector drive system, but uses most of the same core delivery conduits to access the core. A specimen holder is remotely detachable from the delivery cable when appropriately positioned and can be remotely reattached for withdrawal after a scheduled period of radiation.

Abstract: The laser amplification apparatus is provided with a plurality of plate-shaped laser medium components (M1 to M4) which are disposed to be aligned along a thickness direction, and prisms (P1 to P3) which optically couples the laser medium components. Each of the laser medium components is provided with a main surface to which a seed light is incident, and a side surface which surrounds the main surface. An excitation light is incident from at least one side surface of a specific laser medium component among the plurality of laser medium components. The excitation light is incident through the prism to a side surface of the laser medium component adjacent to the prism.

Abstract: A Thorium fuel rod assembly is disclosed that includes first and second support elements and a number of Thorium fuel rods positioned between support elements. Each of the Thorium fuel rod includes an outer fuel element containing a solid Thorium an inner core element containing Beryllium that is positioned within an interior cavity defined by the outer fuel element. In an exemplary disclosure, the inner core element also defines an inner cavity such that a beam of high energy particles may be directed into the inner cavity of the inner core element to impinge upon a Beryllium nucleus within the inner core element to produce a (p, n) reaction resulting in the emission of a neutron, where the emitted neutron may interact with a Thorium nucleus in the outer fuel element to cause the Thorium nucleus to fission.