306results about "Moderator/core" patented technology

A nuclear reactor is discussed herein. In some examples, the nuclear reactor may comprise an inner-core region, including liquid fuel, coolant / moderator, and a hydrogen vapor space, an out-of-core region surrounding the inner-core region, the out-of-core region including, an inner reflector adjacent to the inner-core region, the inner reflector including a first irradiation facility, and an outer reflector adjacent to the inner reflector, the outer reflector including a second irradiation facility.

The invention provides a reactor core structure capable of controlling an assembly clearance and a manufacturing method thereof. The reactor core structure comprises a reactor core heat management element and a filling material; wherein the base body is provided with a plurality of assembly holes; the reactor core heat management element comprises a fuel rod or a heat pipe; the reactor core heat management element is assembled in the assembly hole of the base body; the filling material is filled in an assembly gap between the reactor core heat management element and the assembly hole; and the filling material is a shape memory alloy. The reactor core structure can improve the safety margin of the heat pipe reactor.

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.

Insulated fuel assembly core with plurality of fuel monoliths, exhaust support plate, exhaust shield assembly, and insulation layer in which the plurality of fuel monoliths are located axially along a longitudinal axis and each of the plurality of fuel monoliths has a shape of an eccentric cylinder and a composition including a fissionable fuel component. Channels in the exhaust support plate are oriented so that propellant gas flow through the exhaust support plate does not impinge the exhaust shield assembly. The insulated fuel assembly core is manufactured by forming a tensioned fuel monolith stack mandrel assembly using mandrels spacers and internal tensioning components and forming an insulation layer on an outer surface of the tensioned fuel monolith stack mandrel assembly by mandrel winding. The insulated fuel assembly core can be incorporated into a fuel assembly of nuclear propulsion fission reactor structure of, for example, a nuclear thermal propulsion engine.

The invention belongs to the technical field of heat pipe reactors, and discloses a hexagonal annular heat pipe cooling reactor, which comprises a pipe wall of a heat pipe, a silk screen wick, a steam cavity structure of the heat pipe, uranium-molybdenum alloy fuel, an outer pipe wall of the heat pipe, a wick attached to the inner wall surface of the heat pipe, and uranium-molybdenum alloy. The device is formed by coupling a hexagonal annular heat pipe with a hexagonal fuel element. Firstly, in the aspect of the structure, a framework structure composed of graphite is not needed to fix the heat pipe and the fuel element, an assembly composed of the heat pipe and the fuel element can be directly adopted for expansion to form the fuel element, and gap thermal resistance brought by the framework is eliminated. In addition, in terms of heat transfer performance, the heat transfer performance of the hexagonal annular heat pipe is superior to that of a traditional cylindrical heat pipe. The same heat transfer area is adopted, and under the condition of the same heat transfer power, the temperature of the outer surface of the pipe wall of the hexagonal annular heat pipe is lower than that of a cylindrical heat pipe. Therefore, the material stress requirement in the heat pipe pile and the thermoelectric conversion form of the condensation section can be richer.

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 power generation system capable of generating power with robust shielding against ionizing radiation is provided. This nuclear power generation system includes: a nuclear reactor that includes a core fuel, and a reactor vessel that surrounds to cover the core fuel and to shield a space having the core fuel for shielding against ionizing radiation; a thermal conductor that is disposed inside of the reactor vessel, and transfers heat of the core fuel via solid thermal conduction; a refrigerant circuit that includes a pipe with a part inserted in the reactor vessel and another part disposed outside of the reactor vessel, and through which refrigerant is passed, and that circulates the refrigerant exchanging heat with the thermal conductor; a turbine that is rotated by the refrigerant circulating through the refrigerant circuit; and a generator that is rotated integrally with the turbine.

Flow channels are formed into a nuclear reactor core receptacle and provide a flow path for leaking primary coolant. The flow path redirects the leaking coolant from an upwardly vertical direction, in which the mass flow would impart a lift off force to a core assembly seated within the receptacle, to a horizontal flow path direction which maintains hydraulic balance of the core assembly. The flow channels in the nuclear reactor core receptacle provide a passive measure to allow hydraulic hold down of the core assemblies even in the absence of mechanical hold downs.

To provide a nuclear reactor which is safe and requires a low electricity charge by reducing the output density of nuclear power generation discharging no carbon dioxide to increase the safety, thereby making power generation cost higher than surface-derived energy power generation.SOLUTION: In a two-region breeder reactor with a core and blanket, a heavy noble gas coolant (3000) is circulated for cooling in a cylindrical shielding container (2000) containing a cylindrical U-Pu-MA mixed metal (100) and a doughnut-shaped blanket metal (1000) and The cylindrical U-Pu-MA mixed metal (100), which is made movable, is inserted into and withdrawn from the hollow part of the doughnut-shaped blanket metal (1000) to control the reactor output.SELECTED DRAWING: Figure 1

A masking element with an opening is disposed on the side of a core support structure. A flow stack wall defines a plurality of inlets. At least one inlet aligns with the masking element opening when the flow stack is mated with the masking element. A flow control assembly within the flow stack is configured to restrict flow of fluid within the flow stack.

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.

A nuclear fission power plant (10) comprising: a nuclear reactor core (20) comprising a fuel system (30) and a moderator (35); a plurality of heat pipes (40) that each at least partially extend within the core; a neutron reflector (70) disposed around the core; a plurality of primary neutronic control elements (50) disposed around the core; a secondary neutronic control element (60) configured to be inserted into a void in the core; a fluid circuit (90) comprising a first heat exchanger (92), a second heat exchanger (96), and a pump (94); and an open Brayton power system comprising: a compressor (102); one or more turbines (104, 106); and a generator (108), and being arranged such that air flows through the compressor, the second heat exchanger and the one or more turbines, wherein the second heat-exchanger is configured to permit heat from the core to be transferred to the compressed air from the compressor, and the one or more turbines drive the compressor and the generator.

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

A curvilinear electromagnetic pump is configured to follow a curve, such as by joining together multiple linear pump segments offset at an angle relative to one another. A curvilinear electromagnetic pump can be curved in two dimensions or in three dimensions. A curvilinear electromagnetic pump allows for more efficient placement of components and systems within a reactor vessel, significantly reducing the height of the reactor vessel compared to vertically positioned linear pumps. A curvilinear electromagnetic pump can follow the curvature of the reactor vessel wall and can be positioned generally near the bottom of the reactor vessel.

There is provided a nuclear reactor 21, 23 comprising a reactor vessel (37, Fig. 6) having a central longitudinal axis (30) defining an upper (40) and lower (42) end. Within the reactor vessel is an i

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

A nuclear reactor system includes a drillhole that extends from a terranean surface through one or more subterranean formations; a reactor core positioned in the drillhole, the reactor core comprising at least one nuclear fuel element; a primary coolant system configured to transport a primary fluid coolant between the reactor core and a heat exchanger; and a secondary coolant system thermally coupled to the primary coolant system with the heat exchanger and configured to transport a secondary fluid coolant between the heat exchanger and the terranean surface.

An automatically adjusting seismic restraint system for nuclear fuel storage in one embodiment comprises a free-standing first fuel storage component (FSC) configured to contain nuclear fuel, and a stationary second FSC configured to receive the first fuel storage component. An inter-body gap formed between the FSCs includes at least one seismic restraint assembly. The assembly includes a stationary wedge member fixedly coupled to the second FSC and a movable loose wedge member engaged with and supported in place by the stationary wedge member. The stationary wedge member defines an inclined load bearing surface slideably engaged with a mating inclined load bearing surface of the loose wedge member. During a seismic event or thermal expansion of the first FSC, the first FSC moves towards the second FSC which shrinks the inter-body gap and the loose wedge member is vertically displaced relative to the stationary wedge member while maintaining engagement therewith.

The invention relates to a graphite-carbon aerogel composite material for preventing molten salt permeation and a preparation method and application thereof. The preparation method comprises the following steps: S1, sol preparation: dissolving asphalt, furfural and concentrated sulfuric acid in a solvent, and reacting to obtain sol; s2, gel reaction: immersing graphite in the sol, and heating for gel reaction to obtain a graphite / asphalt-based organic gel complex; s3, drying: drying the graphite / asphalt-based organic gel complex at normal pressure to obtain a graphite-aerogel composite material; and S4, carbonizing: carbonizing and cracking the graphite-aerogel composite material under the protection of inert gas to obtain the fused salt permeation-resistant graphite-carbon aerogel composite material. Compared with the prior art, the graphite-carbon aerogel composite material prepared by the invention has the advantages of excellent molten salt penetration resistance, high-temperature molten salt corrosion resistance, easily available raw materials, low cost and simple preparation process.

A reactor control system (100) for a nuclear fission reactor system comprising a reactor unit (300) having a core (302) with a central axis (320) extending along the length of the core (302). The reactor unit (300) comprises a first region (310) disposed within the core (302) and a second region (312) disposed outside the core (302). The control system (100) comprises a control duct (200) having a first portion (210) configured to extend through the first region (310) and a second portion (220) configured to extend through the second region (312). The duct (200) is filled with a series of control units (400), each of which is configured to travel along the control duct (200).

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).