204results about "Moderator/core" patented technology

An installation includes: a plurality of pilings securable to a bed under a surface of a body of water; a base structure disposed atop the plurality of pilings; and a module disposable on the base structure, wherein the module is positioned and securable on the base structure after being floated on the surface of the body of water over the base structure.

The invention provides a doped yttrium hydride neutron moderation material and a preparation method and application thereof, and belongs to the technical field of radiation shielding materials. At least one of samarium, europium and gadolinium is doped in yttrium hydride in the form of hydride, and the mass ratio of metal yttrium to metal gadolinium to metal europium to metal samarium is controlled, so that the neutron moderation effect of the neutron moderation material can be improved. According to the invention, at least one of gadolinium hydride, europium hydride and samarium hydride is mixed with yttrium hydride under the protective atmosphere, so that the mass content of each element in the doped yttrium hydride neutron moderation material can be accurately controlled. According to the invention, the mixture is sintered and molded, and the sintering parameters of sintering and molding are controlled, so that the components of the mixture are sintered in a compact state, cracks generated by thermal expansion and cold contraction can be reduced, and the doped yttrium hydride keeps high density and has fewer cracks and defects.

This invention discloses an in-core component with highly uniform core outlet flow rate and its design method, relating to the field of nuclear reactor design technology. It solves the problem of poor uniformity in coolant flow distribution at the core outlet in existing reactors, balances flow resistance at various points at the core outlet, and reduces lateral flow between different channels. The specific solution is as follows: it includes a core top plate and a support column assembly mounted above the core top plate. The core top plate is provided with several water flow holes and mounting holes. The water flow holes consist of circular and square water flow holes. The circular water flow holes are divided into first and second circular water flow holes with different functions. The area ratio of the square water flow holes to the circular water flow holes is 1.1:1 to 1.3:1.

Carbide-based fuel assembly includes outer structural member of ceramic matrix composite material, the interior surface of which is lined in higher temperature regions with an insulation layer of porous refractory ceramic material. A continuous insulation layer extends the length of the fuel assembly or separate insulation layer sections have a thickness increasing step-wise along the length of the fuel assembly from upper (inlet) section towards bottom (outlet) section. Fuel element positioned inward of the insulation layer and between support meshes has a fuel composition including HALEU and the form of a plurality of individual elongated fuel bodies or one or more fuel monolith bodies containing coolant flow channels. Fuel assemblies are distributively arranged in a moderator block, with upper end of the outer structural member attached to an inlet for propellant and lower end of the outer structural member operatively interfaced with a nozzle forming a nuclear thermal propulsion reactor.

A nuclear reactor core includes a plurality of fuel elements and moderator blocks to form a nuclear reactor core inner portion and a nuclear reactor core outer portion. The nuclear reactor core inner portion includes an inner moderator matrix formed of a plurality of inner holes that include a plurality of inner fuel openings with one or more fuel elements disposed therein. The plurality of inner holes further include a plurality of inner coolant passages to flow a coolant. The nuclear reactor core outer portion includes an outer moderator matrix formed of a plurality of outer holes that include a plurality of outer fuel openings with one or more fuel elements disposed therein. The plurality of outer holes further include a plurality of outer coolant passages to flow the coolant. The outer coolant passage diameter exceeds the inner coolant passage diameter.

The invention discloses a treatment method for blocking open pores of nuclear graphite by adopting a silicon carbide nanostructure so as to prevent molten salt and molten metal from infiltrating graphite. Comprising the following steps: 1) mixing polycarbosilane and an organic solvent according to a mass concentration ratio of 50%-70% to form a solution, adding a catalyst to serve as a precursor solution, and completely immersing the precursor solution into graphite pores through vacuum infiltration or pressure infiltration; 2) placing the infiltrated graphite in a closed environment of 70-200 DEG C, hydrolyzing and curing the precursor solution to form a gel network, then drying in a vacuum environment of 0-300 DEG C, and forming an aerogel precursor in graphite holes; and 3) in an inert gas atmosphere or a vacuum environment, heating to 1300-1800 DEG C, and pyrolyzing the aerogel precursor to form the silicon carbide nanostructure. Compared with a traditional method, the method has the advantages of simple process, difficulty in failure, no change of the original performance of graphite and the like, and has relatively high economic value and application prospect.

The invention provides a reactor internal capable of realizing integral movement of a reactor core, and relates to the technical field of research, development and design of reactor body structures, the reactor internal comprises a hanging basket barrel, a reactor core shroud and a reactor core; the reactor core is arranged in the reactor core shroud; the reactor core shroud is arranged in the hanging basket barrel body, the reactor core shroud is movably connected with the hanging basket barrel body, the reactor core shroud slides up and down in the hanging basket barrel body, and the bottom of the hanging basket barrel body supports the reactor core shroud. According to the invention, the material changing and maintenance efficiency can be effectively improved, the downtime is shortened, the safety is enhanced, the personnel radiation exposure risk is reduced, the inspection and maintenance are convenient, and the service life of equipment is prolonged. The system adapts to advanced reactor design and conforms to the development trend of modularization and high efficiency, and the performance, safety and economical efficiency of the nuclear reactor are remarkably improved through the design of the system.

A nuclear reactor is designed to couple the load path of the control elements with the reactor core, thus reducing the opportunity for differential movement between the control elements and the reactor core. A cartridge core barrel can be fabricated in a manufacturing facility to include the reactor core, control element supports, and control element drive system. The cartridge core barrel can be mounted to a reactor vessel head. Thus, any movement, such as through seismic forces, transmits an equal direction and magnitude to the control elements and the reactor core. This arrangement reduces the opportunity for differential movement between the control elements and the reactor core.

A fuel assembly comprises a fuel assembly intermediate structure 250 circumferentially enclosing an interior volume, a fuel element bundle 190 located within the interior volume with the fuel assembly intermediate structure radially outward of the fuel element bundle, an insulation layer 160 radially outward of the fuel assembly intermediate structure 250, a void space 255 between an inner surface of the insulation layer 160 and an outer surface of the fuel assembly intermediate structure 250, a fuel assembly outer structure 110 radially outward of the insulation layer 160, and a second void space 265 between an outer surface of the insulation layer 160 and an inner surface of the fuel assembly outer structure 110. The fuel element bundle includes a plurality of fuel elements 105 and a coolant flow volume 115, through which a coolant in a form of a propellant gas flows during operation of a reactor containing the fuel assembly, so that the coolant contacts exterior surfaces of the fuel elements 105.

In many embodiments, a plurality of neutron moderators may be arranged to define a plurality of flow channels within a reactor vessel, wherein each neutron moderator of the plurality of neutron moderators includes at least one surface face, and each neutron moderator is not machined. In some embodiments, the flow channel may be defined by the at least one surface face of each neutron moderator of the plurality of neutron moderators. In at least one embodiment, the plurality of neutron moderators may include at least three neutron moderators. In several embodiments, the plurality of neutron moderators may include a first pair of neutron moderators and a second pair of neutron moderators. In one or more embodiments, the first pair of neutron moderators and the second pair of neutron moderators may be arranged to form a lattice configuration in a reactor vessel.

To enable reactivity control using a simplified configuration.SOLUTION: A nuclear reactor 201 is provided, comprising: a core section 11 not including nuclear fuel; and a plurality of fuel drums (fuel units) 251 arranged so as to surround the core section 11, and each having a neutron absorbing part 55 for absorbing neutrons and a nuclear fuel part 56, where positions of the neutron absorbing part 55 and the nuclear fuel part 56 are adjustable relative to the core section 11.SELECTED DRAWING: Figure 3

Fuel bundle has plurality of twisted ribbon fuel rodlets in hexagonal packing or circle packing arrangement in a core region encased in a multilayer casing. Arrangement of twisted ribbon fuel rodlets is facilitated by rodlet seating fixture with seating surface having a plurality of protrusions that form a receiving space for ends of the twisted ribbon fuel rodlets. Manufacture of the fuel bundle incorporates fiber manufacturing technologies and, optionally, infiltration of void spaces in core region by infiltrant. Twisted ribbon fuel rodlet manufacturing system has sub-systems that impart twist periodicity to extruded ribbons, inspect twisted extruded ribbons, and cut twisted extruded ribbons to length. Inspection sorts twisted ribbon fuel rodlets as well as provides feedback to adjust operation of sub-systems. The fuel bundle (and optional fuel bundle support) can be incorporated into a fuel assembly of a nuclear propulsion fission reactor structure of, for example, a nuclear thermal propulsion engine.

To provide nuclear reactor shielding facilities which are easier to construct while maintaining high radiation shielding performance.SOLUTION: A nuclear reactor shielding facility for shielding the surroundings of a nuclear reactor installed on an installation surface is provided, the facility comprising a base structure provided along an outer circumference of an area other than the installation surface to surround the entire surroundings of the nuclear reactor other than the installation surface, and a shielding structure provided on an entire surface of the base structure and provided with water filled therein.SELECTED DRAWING: Figure 2

We provide a mandrel-wound, splined, monolithic fuel assembly core. [Solution] The fuel assembly core comprises a channel, a fuel monolith containing fissile fuel components and axially arranged, an exhaust support plate, an exhaust shield assembly, and an insulating layer. The fuel monolith has an eccentric cylindrical or straight cylindrical shape with a side surface keyway. The channel in the exhaust support plate is oriented so that the propellant gas does not collide with the exhaust shield assembly. The fuel assembly core is manufactured by forming a fuel monolith stack mandrel assembly and mandrel winding an insulating layer onto the outer surface of the tensioned fuel monolith stack mandrel assembly. The fuel assembly core is incorporated into the fuel assembly of a nuclear propulsion fission reactor structure (e.g., a nuclear thermal propulsion engine).

A nuclear reactor core (1) for a molten salt nuclear reactor (100). The nuclear reactor core (1) has a tubular cylindrical center moderator vessel (10) for passage of a liquid moderator (11), a cylindrical fuel salt jacket surrounding the center moderator vessel (10), and a cylindrical neutron reflector jacket surrounding the cylindrical fuel salt jacket, wherein the cylindrical center moderator and neutron reflector vessel (10) has a largest inner cross-sectional area medially between a liquid moderator and neutron reflector inlet (12) of the center moderator and neutron reflector vessel (10) and a liquid moderator and neutron reflector outlet (13) of the moderator and neutron reflector vessel (10).

The present application relates to a kind of nuclear reactor support mechanism, wherein nuclear reactor support mechanism includes several vertical support structures;Any vertical support structure includes lug, and lug type support is supported by lug;Lug includes base and at least one rib plate;One end of base is arranged in lug type support, and displacement can occur in lug type support along the length direction of base and / or the width direction of base;Nuclear reactor support mechanism further includes at least one first lateral support structure, and the first lateral support structure includes at least one first lateral support body, and the length direction of the first lateral support body is same with the radial direction of equipment, and one end of the first lateral support body can be connected on the circumferential side of equipment.The nuclear reactor support mechanism of the present application can be used on the equipment with high length-diameter ratio and vertical arrangement in the reactor, to ensure the release of cold and hot equipment self-expansion and pipe elongation, to ensure the verticality of equipment, and to facilitate the optimization of equipment stress, to improve the reliability of equipment.

This application provides a docking monitoring device, docking system, and docking method for underwater docking structures. The underwater docking structure includes a first annular component and a second annular component located underwater. The second annular component is deployed underwater using a hoisting and deployment device to dock and assemble with the first annular component, or is lifted upwards using the same device to separate from the first annular component. The first annular component forms a positioning element, and the second annular component forms a positioning mating element. Positioning is achieved through the positioning mating element and the positioning element. The device includes: multiple lifting mechanisms, each facing a positioning element; multiple image acquisition devices, each mounted on a lifting mechanism, each lifting mechanism configured to move the image acquisition device in the same direction as the second annular component to continuously acquire images containing the second annular component; and a display device for displaying the images acquired by the multiple image acquisition devices.

The application provides a graphite processing method for blocking molten salt and molten metal infiltration, comprising the following steps: S1: providing a thermosetting resin monomer or oligomer solution, adding a small amount of catalyst to the solution to form a precursor, and immersing the precursor into graphite pores; S2: converting the precursor immersed in the graphite pores into organic nanostructures through solidification and drying; and S3: carbonizing the organic nanostructures in the graphite pores at a temperature higher than 500 DEG C to form carbon nanostructures, so that a graphite capable of blocking molten salt and molten metal infiltration is obtained. The processing method provided by the application has the advantages of simple process, difficulty in failure, and no change in the performance of the base material, compared with the traditional surface coating, resin and other impregnation methods, and has obvious advantages over other processing methods when used for processing the graphite in a molten salt core, and has little influence on the mechanical, thermal and radiation behaviors of the graphite, so that the cost caused by the reevaluation of the graphite material can be saved or reduced.

The reactor core comprises a plurality of core assemblies. The plurality of core assemblies have a cooperative structure formed on one or more load pads that mechanically connects the plurality of core assemblies to each other and restricts the relative motion between the core assemblies in a kinematically determined manner. A shear key on one core assembly is configured to fit into a tab slot on an adjacent core assembly. The motion of one core assembly is transmitted to a second core assembly, and these core assemblies move together.

In some embodiments, a nuclear reactor may include a vessel having a wall defining an interior cavity. The nuclear reactor may include a core disposed within the interior cavity. The core may include heat-generating fuel and a primary medium for transferring heat from said fuel to an outer boundary of said core. Said primary medium may be one or more solid materials. In some embodiments, a system may include a nuclear reactor having a core comprising an active region containing a. fissionable fuel operating at criticality within a predetermined temperature range. At least fifty (50) percent of heat transferred within said active region may be transferred by conduction only.

The invention relates to the technical field of nuclear fuel, and discloses a fuel element and a preparation method of the fuel element, the fuel element comprises a cladding, a base body and fuel particles, the cladding is of an integrated structure manufactured through an additive manufacturing process, the cladding comprises an outer shell, a bottom plate and a cooling pipe, the outer shell and the cooling pipe are connected with the bottom plate, and the base body is arranged on the outer shell. The shell surrounds the periphery of the cooling pipe, a containing space is formed between the inner side of the shell and the outer side of the cooling pipe, and a coolant channel is formed in the inner side of the cooling pipe and penetrates through the bottom plate. The containing space is filled with the base body and the fuel particles, and the fuel particles are dispersed in the base body. According to the cladding structure, the containing space and the coolant channel are formed at the same time, cladding schemes of the fuel element can be customized according to various reactor cores of various reactor types, and the fuel element can meet the variable requirements of various novel reactor applications such as an ultra-high temperature gas cooled reactor and a gas cooled fast reactor at the same time.

In some embodiments, a power generation system may include a first nuclear reactor, which may include a vessel having a wall defining a cavity. The nuclear reactor may include a core disposed within said cavity. Said core may include a solid matrix material defining one or more channels. A fuel material may be disposed in said one or more channels. Said solid matrix material may be a primary heat transfer medium. The power generation system may include an electric generating system having a secondary heat transfer medium. The power generation system may include one or more heat exchangers thermally coupled to said vessel wall. Said primary heat transfer medium may transfer heat generated by the fuel material to the one or more heat exchangers. Said secondary heat transfer medium may draw heat from said one or more heat exchangers.

Systems and methods use inserted controllers in assembly openings of nuclear fuel castings. The controllers can be secured entirely within the opening and condition coolant flow to a desired level for the associated assembly. The controllers can be installed or removed at any time through clamps or other securing structures accessible through the top of the opening. This may include during fuel removal or shuffling during a maintenance outage, or at casting construction and installation, or at decommissioning. Side orifices do not have to be accessed from below the core nor do the castings otherwise require movement or alteration. Any desired flow characteristics may be selected and achieved through use of the configured controllers at specific core locations. Size, shape, and flow surfaces can all be configured to achieve these characteristics where they permit the controller to fit in the casting.

A method and system for an in-vessel natural circulation alkali metal reactor system, a cleanup system, and associated methods are disclosed. The reactor vessel system includes an inner vessel defining an interior volume sized to at least partially surround a nuclear reactor. The reactor includes a plurality of nuclear fuel elements at least partially surrounded by cladding, and the reactor is cooled by a liquid metal coolant in a primary coolant loop. A pool of immersion fluid occupies a volume inside the inner vessel. The reactor vessel system includes an outer vessel sized to completely or substantially surround the inner vessel. The nuclear reactor power system includes a reactor core including an active fuel region and a rotatable drum including at least one of a neutron absorbing material, a neutron leakage enhancing material, or a neutron reflecting material, the rotatable drum being positioned outside the active fuel region of the reactor core.

The invention discloses a neutron source cold package with a simplified structure, a reactor-based cold neutron source and a reactor, and belongs to the technical field of nuclear. A neutron source cold package with a simplified structure comprises a moderator input pipe, a moderator output pipe, a cold package cavity and a coolant circulating pipeline. The moderator input pipe comprises an inflow section parallel to the moderator output pipe and a bent backflow section, the cold package cavity is connected with the backflow section, and the maximum cross section area of the cold package cavity covers the direction interval of neutron guide pipe arrangement. The coolant circulating pipeline comprises an input interlayer, an output interlayer and a cold bag cavity interlayer, and a vacuum interval is formed between the cold bag cavity interlayer and the input interlayer.

The application relates to a split type reactor base cold neutron source and reactor, belonging to the nuclear technology field. The split type reactor base cold neutron source is arranged in a reactor and comprises a vacuum cylinder, a coolant circulating assembly and a cold package assembly. The vacuum cylinder has a vacuum cavity with a ring-shaped cross section. The coolant circulating assembly comprises a coolant input pipe and a coolant output pipe which are communicated to a coolant cavity defined by the inner wall of the vacuum cylinder for coolant input and output. The cold package assembly is a single-layer wall structure and is arranged in the coolant cavity and cooled by the coolant. The cold neutron source has the advantages of simple structure, good cooling effect, convenience in maintenance and repair, high reliability and the like.

The invention relates to a method for constructing an underground nuclear installation on a site (10) comprising a shaft (12) bored into the ground (14, 16) and defining a bottom (12a), at a given depth relative to the ground surface, and an opening (12b, 12b1, 12b2) located at the level of the ground surface surrounding the shaft. The method comprises the following phases: - construction of a protective slab (D1, D2; D; 230) against external aggressions on an area (Zcd) of the ground surface, referred to as the slab construction area, located next to the opening (12b, 12b1, 12b2) of the shaft, - construction of a reactor building (B1, B2) inside the shaft (12), the phases of construction of the protective slab (D1, D2; D; 230) and the reactor building (B1, B2) being carried out in parallel. Figure for the abridged version: Fig. 3

A nuclear reactor has an axially stratified fuel bed. The reactor features a reactor shell having a base, a top having an exhaust outlet, and an axis. The axially stratified fuel bed is within the reactor shell, and includes: a first zone configured to operate at a first temperature T1, the first zone comprising a plurality of first fuel particles, each first fuel particle comprising a first radioactive ceramic core and a first ceramic seal coating; and a second zone configured to operate at a second temperature T2, where T2>T1, the second zone comprising a plurality of second fuel particles, each second fuel particle comprising a second radioactive ceramic core and a second ceramic seal coating. A coolant fluid flow path carries a coolant fluid from the base of the reactor to the exhaust outlet, along a flow path passing sequentially through the first zone and the second zone. The first ceramic seal coating has greater stability at T1 than at T2, and the second ceramic seal coating has greater stability at T2 than the first ceramic seal coating.

The invention provides a reactor core block (200), comprising: a plurality of fuel channels (202); a plurality of heat pipes (204); a primary moderator matrix (206), consisting for example of graphite, silicon carbide, aluminum nitride, stainless steel, and combinations thereof, configured to encompass the plurality of fuel channels (202) and the plurality of heat pipes (204); and a secondary moderator channel (208) configured to at least partially surround the plurality of fuel channels (202), the plurality of heat pipes (204), and the primary moderator matrix (206). The secondary moderator channel (208) is comprised of metal hydride.

To provide compact and higher power density cores in nuclear micro-reactors.SOLUTION: A reactor core block 200 is disclosed including a fuel channel 202, a heat pipe 204, a primary moderator matrix 206 configured to encompass the fuel channel 202 and the heat pipe 204, and a secondary moderator channel 208 configured to at least partially surround the fuel channel 202, the heat pipe 204 and the primary moderator matrix 206. The secondary moderator channel 208 comprises metal hydride.SELECTED DRAWING: Figure 1