301results about "Fuel elements" patented technology

Systems, structures, devices, and fabrication processes for ceramic matrix composites suitable for use in a nuclear reactor environment and other applications requiring materials that can withstand high temperatures and / or highly corrosive environments are disclosed. In one aspect, a ceramic composite structure is provided. The structure comprises a chamber including an external shell and a hollow space inside the external shell. The external shell includes an inner composite layer including a first composite structure, a middle composite layer placed outside of the inner composite layer, the middle composite layer including a second composite structure that is different from the first composite structure, and an outer monolithic layer that has a spatially uniform material property and placed outside of the middle composite layer.

The invention discloses a cold rolling die with a straight rib thin-wall cladding pipe, a production process and the cladding pipe, and relates to the technical field of reactor fuel cladding, the cold rolling die comprises a cold rolling outer die for controlling the forming of the outer contour of a pipeline and a cold rolling core head for controlling the inner diameter; the cold rolling outer die is a die with a hollow area inside, the hollow area comprises a pitch circle section and a fixed rib section, and the fixed rib section is provided with at least one section of rib groove; a pipeline forming die cavity is formed by hollow areas of the two cold rolling outer dies, and a roll gap is formed between the two cold rolling outer dies; when the cold rolling die is used for producing the cladding pipe, the requirement for room-temperature plasticity of cladding materials in the forming process is low, the quality of the surface of the cladding pipe cannot be affected in the forming process, the quality of a formed product is high, and the cold rolling die is simple in structure, low in manufacturing cost and suitable for popularization and application. The thin-wall cladding tube with the straight ribs produced by the cold rolling die is good in surface quality, and the ribs of the cladding tube are good in mechanical property.

A system is described that includes a sputter target and a magnetic element array including multiple sets of magnets arranged to have a Hall-Effect region that extends along a length of the sputter target. The elongated sputtering electrode material tube is interposed between the magnetic array and an object to be deposited with a sputtered material from the sputter target. During a direct current high-power impulse magnetron sputtering operation, the system performs a depositing on a surface of the object by generating and controlling an ion and neutral particle flux by: providing a vacuum apparatus containing a sputter target holder electrode; first generating a high-power pulsed plasma magnetron discharge with a high-current negative direct current (DC) pulse to the sputter a target holder electrode; and second generating a configurable positive voltage kick pulse to the sputter target holder electrode after terminating the negative DC pulse.

The utility model provides a heat conduction structure and a molten salt reactor cabin. The heat conduction structure comprises a first pipeline, a heat conduction layer and at least one heat pipe, the first pipeline is provided with a first end face and a second end face at two ends; the heat conduction layer is arranged on the periphery of the first pipeline from the first end face in the length direction of the first pipeline. The heat conduction layer is shorter than the first pipeline; a plurality of channels are formed in the end face of the side, away from the first end face, of the heat conduction layer in the axial direction of the heat conduction layer. Two ends of the heat pipe are closed; one end of each heat pipe is arranged in the channel, and the other end of each heat pipe faces the second end face, so that the part, located in the heat conduction layer, of each heat pipe serves as a condensation section, and the part, not located in the heat conduction layer, of each heat pipe serves as an evaporation section in the working state. Fused salt freezing blockage in the fused salt pipeline can be effectively prevented, and the temperature uniformity of the fused salt pipeline is improved; and the dismounting difficulty of the molten salt reactor cabin through-wall pipeline can be reduced, so that the heat conduction structure is easy to maintain, and the safety and the reliability of the molten salt reactor cabin are improved.

A nuclear fuel cell cladding that includes a zirconium-carbon covetic material. The zirconium-carbon covetic material has a carbon component associated with the surface of zirconium particles. The amount of carbon present in the zirconium-carbon covetic material is in a range of greater than 0.1 wt % to about 25 wt % of the zirconium-carbon covetic material. The carbon component may include carbon nanotubes, carbon nanomaterials, graphene, or graphene nanoplatelets. The carbon component may be uniformly distributed within the zirconium matrix. The zirconium-carbon covetic material may be formed from a zirconium alloy. The zirconium-carbon covetic material may be configured for use in various types of nuclear reactors. The synthesis of the cladding involves a process of plasma-enhanced chemical vapor deposition. The resulting nuclear fuel cell cladding offers improved performance and reliability for nuclear reactor applications.

The utility model discloses a SiC cladding fuel element. The SiC cladding fuel element comprises a SiC cladding, at least one metal foil and at least one fuel pellet, at least one fuel pellet is packaged in the metal foil to form a packaged pellet unit; and the packaging core block unit is arranged in the SiC cladding. According to the SiC cladding fuel element, the fuel pellet is packaged in the metal foil, and the metal foil can contain fission gas, so that the airtightness maintaining capability of the SiC cladding is improved, and the risk that the fission gas of the SiC cladding fuel element leaks is reduced.

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.

Additive manufacturing compositions include low-absorbing particles or non-absorbing particles that have an absorbance for wavelengths of 300 nm to 700 nm that is equal to or greater than 0 Au and is less 1.0 Au, such as 0.001 Au ≤ absorbance ≤ 0.7 Au. Slurries including such particles and an uranium-containing particle and that are used in additive manufacturing processes have an increased penetration depth for curative radiation. Removal of low-absorbing particles or non-absorbing particles during post-processing of as-manufactured products results in pores that create porosity in the as-manufactured product that provide a volume accommodating fission gases and / or can enhance wicking of certain heat pipe coolant liquids. Low-absorbing particles or non-absorbing particles can be functionalized for improved properties, for example, with fissionable material for improved ceramic yields, with burnable poisons or stabilizers for increased homogeneity, with stabilizers for localized delivery of the stabilizer, or with combinations thereof.

The embodiment of the invention relates to the field of processes specially used for manufacturing a reactor or parts thereof, in particular to an assembling and charging testing method of a reactor using bulk nuclear fuel and the reactor comprising the bulk nuclear fuel. According to the method, loading test is carried out on the reactor by using the test facility after assembly, so that the backup reactivity of the reactor core can be determined, safe assembly and safe criticality of the reactor are realized, and the safety of experimenters is ensured; by gradually adding the partitioned side reflecting layers outside the reactor core formed by the bulk nuclear fuel, the reactor gradually reaches the critical value, the operation risk is reduced, and meanwhile, the critical point can be accurately obtained; after the critical loading of the reactor core is determined, the partitioned side reflecting layers are replaced by the complete side reflecting layers with the same value, so that the influence of gaps existing between the partitioned side reflecting layers can be avoided, and the reaction efficiency of nuclear fuel is improved. The reactor assembled according to the method has high neutron economy and low critical risk.

The invention belongs to the field of nuclear fuel, and particularly discloses a metal material for fuel rod gap filling and a preparation method of the metal material. The metal material comprises the following components in parts by mass: 0.01 to 44.5 parts of lead, 0.01 to 56.5 parts of bismuth, 0.01 to 61.9 parts of tin, 0.01 to 5 parts of magnesium and 0.01 to 5 parts of zirconium; and the melting point of the metal material is less than 300 DEG C. The metal material disclosed by the invention has a lower melting point and a higher heat conductivity coefficient, is applied to the in-pile service process of the fuel rod of the advanced reactor, is molten at a loop temperature to be in a liquid state, fills a gap, immerses and seals a fuel core block section, and serves as an excellent heat-conducting medium, so that heat transfer between the fuel rod core block and a cladding is realized, and the heat transfer efficiency is improved. The core block and the cladding are combined to reduce the temperature of the nuclear fuel, meanwhile, the gasification phenomenon does not exist, the phenomenon of irradiation swelling-fission gas release does not occur, the contact force between the core block and the cladding is reduced, and the service life of the fuel rod is prolonged.

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.

The present invention provides a method for manufacturing a multilayer nuclear fuel cladding tube, which includes the following steps: providing a preliminary cladding tube, in which an inner tube with a rod-shaped insert is inserted is arranged in an outer tube; reducing the diameter of the preliminary cladding tube by applying pressure from the outside to the inside of the preliminary cladding tube; and removing the insert from the inner tube by providing a force in the direction in which the insert extends, wherein the inner tube and the outer tube can be formed of metals different from each other.

A fuel element (100) for a nuclear reactor, the fuel element comprising non-fissile particles (110) dispersed throughout fissile fuel (120), the non-fissile particles comprising a core comprising neutron absorbing material, wherein the neutron absorbing material is positioned at an innermost radial portion of the core, wherein the core is configured to remain stable at a temperature no less than 1000 °C; and an outer layer surrounding the core, the outer layer comprising silicon carbide.

Nuclear fuel pellet incorporating thermally conductive inserts in the form of rods distributed at different azimuths and altitudes, fuel rod and associated nuclear fuel assembly. The invention consists of a nuclear fuel pellet (6), comprising: - a straight cylinder (60) of fissile material with a central axis (X) whose length and diameter respectively define the length (H) and diameter (Ø) of the pellet; - a plurality of inserts (8; 80, 81, 82) of thermally conductive material, the inserts being solid rods, distributed at different azimuth and altitude positions within the straight cylinder, and spaced apart from each other. Figure for the abstract: Fig. 4

A fuel assembly (400) for a nuclear fission reactor system (100). The fuel assembly (400) may extend along a longitudinal axis (420). The fuel assembly (400) may comprise a pressure tube (402) and a single sleeve member (430) provided radially inward of a radially inner surface (432) of the pressure tube (402). The sleeve member (430) may define a chamber (434) which extends along a length of the sleeve member (430). The chamber (434) may comprise, in series, a first sub-chamber (436), a second sub-chamber (438) and a third sub-chamber (440). The first sub-chamber (436) may define a chamber flow inlet (442) and the third sub-chamber (440) defines chamber flow outlet (444). There may be provided a fuel compact unit (500) located in the second sub-chamber (438) within the sleeve member (430) such that a clearance gap (522) is maintained between a radially inner surface (450) of the sleeve member (430) and the fuel compact unit (500) to define a sleeve member flow passage (452).

A control rod drive mechanism having a torque tube, a control rod assembly including a connecting rod disposed within the torque tube and including an annular collar defining a key slot, an elongated key that is slidably receivable within the key slot, a lock cam assembly rotatably secured to a top end of the connecting rod and including a locking cam, and a holdout collar disposed non-rotatably within the torque tube, the holdout collar including a locking recess with an entry slot, wherein in a first axial position the lock cam assembly is rotatable with respect to the torque tube, and a second axial position the lock cam assembly is non-rotatable with respect to the torque tube.

The invention discloses a nuclear rod power generation device, the nuclear rod power generation device comprises a nuclear fuel device, a neutron source device, a control assembly and a water pipe device, the nuclear fuel device is arranged in the water pipe device, and the water pipe device comprises a water inlet and a water outlet; the nuclear fuel device comprises an inner sleeve and an outer sleeve, the inner sleeve is arranged in the outer sleeve, the two ends of the inner sleeve and the two ends of the outer sleeve are connected in a sealed mode, a vacuum cavity is formed between the inner sleeve and the outer sleeve, and nuclear fuel coatings are arranged on the outer side of the inner sleeve and the inner side of the outer sleeve. The neutron source device is arranged on the inner side of the inner sleeve through a guide pipe, and the control assembly adjusts the position of the neutron source device in the guide pipe. The invention provides a nuclear rod power generation device which adopts a safe and miniaturized nuclear reaction technology and can replace a huge nuclear reactor.

A fuel assembly fastening mechanism (24) for use in a nuclear reactor (10) includes a fuel assembly (22) comprising a fuel assembly header (28) and a fuel assembly footer (30). The fuel assembly footer (30) has a footer housing and comprises a holding lever having a nose, the holding lever being rotatable between an unlocked position and a locked position. The fuel assembly (22) further comprises a securing wedge arranged within the fuel assembly footer (30), the securing wedge being movable between an upper position and a lower position. When the securing wedge is in one position chosen from the upper position and the lower position, the holding lever is in the unlocked position, and when the securing wedge is in the other position chosen from the upper position and the lower position, the holding lever is in the locked position. The fuel assembly fastening mechanism further includes a nozzle for mounting the fuel assembly in an open cell (20) of a bottom core plate (18) of the nuclear reactor (10), the nozzle comprising a nozzle housing engaging the footer housing and a nozzle window. The nose of the holding lever is received by the nozzle window in the locked position of the holding lever such that a contact surface between the nose of the holding lever and the nozzle window is arranged perpendicular to a fuel assembly main axis. Further, a method for operating a fuel assembly fastening mechanism (24) and a fuel assembly (22) is shown.

A coupon sampler for a reactor system includes a lower assembly having an in-line portion configured to receive a flow of a molten salt, and a lower assembly pipe portion extending transverse from the in-line portion and defining a lower channel therethrough. The coupon sampler further includes an upper assembly fluidically coupled with the lower assembly. The upper assembly includes an upper assembly pipe portion defining an upper channel therethrough and cooperating with the lower channel to define a sampling channel of the coupon sampler. The coupon sampler further includes a coupon device disposed fully within the sampling channel. The coupon sampler further includes an actuation mechanism operatively coupled with the coupon device and configured to move the coupon device axially into and out of the flow of the molten salt.

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.

A fuel assembly (100) for a nuclear fission reactor system (110). The fuel assembly (100) may comprise a pressure tube (120) comprising an aluminium or aluminium alloy. The fuel assembly (100) may comprise a sleeve member (132), the sleeve member (132) extending along a radially inner surface (134) of the pressure tube (120). The fuel assembly (100) may comprise a fuel compact unit (136). The fuel compact unit (136) may be located within the sleeve member (132)) such that a clearance is maintained between a radially inner surface (139) of the sleeve member (132) and the fuel compact unit (136) to define a sleeve member flow passage (140).

The invention relates to the technical field of nuclear reactor cores, and provides a reactor core adopting different hydrides for combined application, the reactor core comprises a plurality of fuel assemblies which are sequentially arranged in a zoning manner along the radial direction from the center to the periphery; part of the fuel assemblies simultaneously comprise uranium zirconium hydride fuel rods filled with uranium zirconium hydride fuel and uranium yttrium hydride fuel rods filled with uranium yttrium hydride fuel. Metal hydride fuel rods are introduced into the moderator-free reactor core, the reactor core neutron energy spectrum is slowed down, the reactor core fission reaction rate is increased, the reactor core critical mass is reduced, meanwhile, the equivalent nuclear density of uranium and hydrogen in different areas of the reactor core is adjusted in the mode that different hydride types are used in a combined mode, and reactor core power distribution is further flattened.

A nuclear power plant has a nuclear reactor including a reactor pressure vessel which houses plural fuel rods containing fissile material. The nuclear power plant further has means for submerging the reactor pressure vessel in water and thereby water-cooling the reactor pressure vessel in the event of an emergency requiring cooling of the nuclear reactor. The nuclear power plant further has a primary core catcher outwardly of the reactor pressure vessel, the primary core catcher being formed of a material suitable for retaining molten corium in the event corium escapes the reactor pressure vessel. The nuclear power plant further has secondary core catcher outwardly of the primary core catcher, the secondary core catcher lining a tank which is water-filled in normal use of the plant to submerge and thereby water-cool the primary core catcher. The secondary core catcher is also is formed of a material suitable for retaining molten corium in the event corium escapes the primary core catcher.

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.

A fuel assembly (100) for a nuclear fission reactor (10). The fuel assembly (100) is centred on a longitudinal axis (102). The fuel assembly (100) comprises a fuel compact (200) which defines a flow passage (202) running from a flow inlet (204) provided at a first end (206) of the fuel compact (200) to a flow outlet (208) provided at a second end (210) of the fuel compact (200). The flow passage (202) defines an internal surface (222) of the fuel compact (200). A displacer element (300) is provided in the passage (202) and mounted such that a clearance (212) is maintained between the internal surface (222) of the fuel compact (200) and the displacer element (300) to define an annular coolant flow passage (230).

A fuel design for high burnup in water-cooled reactors is disclosed. A nuclear fuel rod comprising an outer zone of annular fuel pellets composed of actinides and fissile material and an interior comprising a low density, high open porosity ceramic foam of zirconia or magnesia is used. Use of annular pellets lowers fuel temperature, reduces fission gas release and fuel swelling. Foam with low crushing strength is used to accommodate fuel swelling. Fresh fuel reactivity is controlled by burnable absorbers such as gadolinia, incorporated as sintered bodies within the foam or as part of the fuel composition or both. The placement of burnable absorber in the foam reduces the contact area with surrounding media, mitigating diffusional transport and preserving its self-shielding characteristic. A novel two-piece foam holder is proposed to insert the ceramic foam.

A burnable absorber tristructural isotropic (TRISO) particle that comprises a kernel that comprises a non-fissile neutron-absorbing material, a porous carbon buffer layer surrounding the kernel, a first pyrolytic carbon layer surrounding the porous carbon buffer layer, a silicon carbide layer surrounding the first pyrolytic carbon layer, and a second pyrolytic carbon layer surrounding the silicon carbide layer. A fuel compact comprising burnable absorber TRISO particles and TRISO fuel particles is also disclosed, as is a method of forming the burnable absorber TRISO particle.

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).

Heat pipe fuel element includes an evaporation section, a condensing section, a capillary section connecting the evaporation section to the condensing section, and a primary coolant. In a cross-section in a plane perpendicular to a longitudinal axis of the evaporation section, the heat pipe fuel element includes a cladding layer enclosing an interior area including a fuel body formed of a fissionable fuel composition and that has an outer surface oriented toward the cladding layer and an inner surface defining a periphery of a vaporization space of the evaporation section. The fuel body has a structure with a shape corresponding to a mathematically-based periodic solid, such as a triply periodic minimal surface (TPMS), and the evaporation sections of a plurality of heat pipe fuel elements are arranged in a phyllotaxis pattern (as seen in a cross-section in a plane perpendicular to a longitudinal axis of the active core region).

The invention discloses a bottom device and a fuel assembly, belongs to the technical field of reactor engineering, and mainly aims at changing the flow channel form when a cooling medium flows through a foreign matter prevention plate and avoiding the situation of uneven flow field distribution. According to the main technical scheme, the bottom device comprises a lower pipe base and a foreign matter prevention plate connected with the lower pipe base; the foreign matter prevention plate is provided with a first surface and a second surface which are arranged back to back along the flow path direction of the cooling medium, the first surface faces the lower reactor core plate, and the lower reactor core plate is provided with a cooling medium flow channel hole; a first convex part is arranged at the position, opposite to the cooling medium runner hole, in the first surface, and the first convex part protrudes towards the side where the lower reactor core plate is located; the first face is further provided with a second protruding part, the second protruding part is connected with the first protruding part, and the protruding direction of the second protruding part is the same as the protruding direction of the first protruding part.