2632results about "Reactor fuel elements" patented technology

Apparatus suitable for transporting and storing nuclear fuel rods comprising a basket having storage cells formed from a honeycomb gridwork of metal plates in a rectilinear configuration, the plates welded to each other at their intersections so that all contiguous corners of the storage cells formed by the gridwork are completely connected so as to allow conduction heat transfer, the metal plates having neutron absorber material positioned in areas which form walls of the storage cells. Method of making an apparatus suitable for transporting and storing nuclear fuel rods comprising a) providing metal plates having slots and having neutron absorber material positioned on sides of the metal plates, b) arranging the plates so that the slots intersect to form a honeycomb gridwork of storage cells having contiguous corners and having the neutron absorbing material on sides of the storage cells, and c) welding the plates to each other at their intersections so that all contiguous corners of the storage cells formed by the gridwork are completely connected so as to allow conduction heat transfer and to provide a rigid structure.

A data management system stores and visualizes data generated during process management. The data management system provides different data management services and definitions of these are stored in a database. Management of data in this database is carried out by a collection of software agents, one of which, the management information agent, can access, update and download data in or from the database. Stored separately are graphical user interfaces which are downloaded to a user in accordance with the relevant service definition stored in the database when the user requests a particular data access service.

A method for mitigating stress corrosion cracking in high temperature water includes introducing catalytic nanoparticles and dielectric nanoparticles to the high temperature water in an amount effective to reduce a electrochemical corrosion potential of the high temperature water.

A method and system is provided for a nuclear reactor safety related application. The method includes executing two forms of a same application-specific logic, one of the two forms implemented as hardware logic, and the other of the two forms implemented as software instructions for execution by microprocessor-based controlling software. Each form of the application-specific logic is executed with a same set of inputs. The method compares a result produced from the execution of the hardware-implemented form to a result produced from the execution of the software-implemented form. When the compared results concur, the controlling software performs actions associated with the concurring results by executing microprocessor-based software. When the compared results fail to concur, the controlling software reports the failure of the compared results to concur to an operator by executing microprocessor-based software, and thereafter places the microprocessor-based software system into an inoperative (INOP) mode.

A zirconium alloy with a coating layer formed on a surface comprising a mixed layer, the mixed layer comprises one or more very high temperature oxidation resistant material and zirconium alloy parent material selected from the group consisting of Y2O3, SiO2, ZrO2, Cr2O3, Al2O3, Cr3C2, SiC, ZrC, ZrN, Si and Cr, and in a vertical direction on a boundary between the mixed layer and the zirconium alloy parent material is formed a gradient of compositions between the very high temperature oxidation resistance material and the zirconium alloy parent material.

A composite-wall radiation-shielded cask and method of assembly having an inner shell surrounding a containment volume, and two or more non-annular sections of a radiation-shielding material secured with a fastener or strap to the inner shell to form a bound inner assembly. The bound inner assembly is inserted into an outer shell to form a clearance gap between the inner assembly and the outer shell. And the clearance gap is then filled with filler material capable of transferring mechanical and thermal loads between the bound inner assembly and the outer shell.

A system, method and apparatus for providing additional radiation shielding to a container holding radioactive materials. The invention utilizes a sleeve-like structure that is slid over a container holding high level radioactive materials to add radiation shielding protection. Because the sleeve-like structure and container are non-unitary and slidably separable from one another, crane lifting capacity is not affected. In one aspect, the invention is an apparatus comprising: a tubular shell constructed of a gamma radiation absorbing material and having an inner surface that forms a cavity having an axis, the cavity having an open top end and an open bottom end; a plurality of spacers extending from the inner surface of the shell toward the axis of the cavity, the spacers extending a first height from the inner surface of the tubular shell; and one or more flange members located at or near the open top end of the cavity extending from the tubular shell toward the axis of the cavity, the flange member extending a second height from the inner surface of the shell, the second height being greater than the first height.

An in-core restraint assembly is for a nuclear reactor core including an upper core plate, a lower core support plate and a plurality of fuel assemblies extending longitudinally therebetween. Each fuel assembly includes top and bottom nozzles and a plurality of elongated fuel rods extending therebetween. The in-core restraint assembly includes a first restraint element, such as a spring pack, coupled to the upper core support plate and providing a substantially axial compressive force on the top nozzle of the fuel assembly. An optional second restraint element is structured to be coupled to the lower core plate in order to engage and further restrain the fuel assembly proximate the bottom nozzle. The second restraint element includes a pin member extending from the bottom nozzle of the fuel assembly and received in a socket coupled to the lower core support plate, whereby this mating sustains a longitudinal (vertical) frictional force which must be overcome before fuel assembly lift off can occur.

A method is for establishing a nuclear reactor core loading pattern (LP) for fuel assemblies and burnable absorbers (BAs). The method establishes an optimum LP through the steps of: a) providing nuclear data representing fuel assemblies and BAs in a nuclear reactor core; b) depleting the nuclear data to form a reference core depletion; c) incorporating the nuclear data into a system of linear equations of a nuclear design quality flux solution method; d) defining the system of linear equations to include constraints which accurately represent the neutron physics of the reactor; employing the equations as a constraint matrix for a MIP solver to find an optimum core pattern solution; f) repeating steps b) through e) updating the constraints and objective functions to satisfy specified engineering requirements and establish an optimum core loading pattern. An algorithm for deriving the system of equations is also disclosed.

A method is for establishing a nuclear reactor core loading pattern (LP) for fuel assemblies and burnable absorbers (BAs). The method establishes an optimum LP through the steps of: a) providing nuclear data representing fuel assemblies and BAs in a nuclear reactor core; b) depleting the nuclear data to form a reference core depletion; c) incorporating the nuclear data into a system of linear equations of a nuclear design quality flux solution method; d) defining the system of linear equations to include constraints which accurately represent the neutron physics of the reactor; employing the equations as a constraint matrix for a MIP solver to find an optimum core pattern solution; f) repeating steps b) through e) updating the constraints and objective functions to satisfy specified engineering requirements and establish an optimum core loading pattern. An algorithm for deriving the system of equations is also disclosed.

A nuclear reactor in which a secondary or tertiary coolant system of a nuclear steam supply system is simplified, comprising: a reactor vessel (2) which integrates a reactor core (1); a first coolant (3) which is stored in the reactor vessel (2) and heated by the reactor core (1) to convect; a first heat transfer tube (4) which is arranged in the reactor vessel (2) and comes into contact with the first coolant (3); and a second coolant (5) which is supplied from the outside of the reactor vessel (2) to the first heat transfer tube (4), cools the first coolant (3) and led to the outside of the reactor vessel (2).

An in-core neutron monitor that employs vacuum microelectronic devices to configure an in-core instrument thimble assembly that monitors and wirelessly transmits a number of reactor parameters directly from the core of a nuclear reactor without the use of external cabling. The in-core instrument thimble assembly is substantially wholly contained within an instrument guide tube within a nuclear fuel assembly.

A skills based telephone call distribution system is disclosed. The system determines the informational needs of an incoming caller and defines a set of skills an agent should possess to serve the caller. A search is performed for an available agent possessing the skill set. Upon the search failing to locate an available agent possessing the skill set, the amount of time the caller may expect to wait therefor is estimated. The estimated time is compared to a maximum waiting time. If the estimated time is greater than the maximum waiting time, then the skill set is redefined to include a greater number of agents who may serve the caller. A new search is performed for an available agent possessing the redefined skill set.

According to the method, a reactor core is shut down during the operation cycle. One or more fuel bundles of the reactor core are then moved to new positions within the reactor core to increase a total energy, output of the reactor core as compared to continuing operation of the reactor core without the shutting down and moving steps.

A method and system for reducing stress corrosion cracking in a hot water system, such as a nuclear reactor, by reducing the electrochemical corrosion potential of components exposed to high temperature water within the structure. The method comprises the steps of: providing a reducing species to the high temperature water; and providing a plurality of noble metal nanoparticles having a mean particle size of up to about 100 nm to the high temperature water during operation of the hot water system. The catalytic nanoparticles, which may comprise at least one noble metal, form a colloidal suspension in the high temperature water and provide a catalytic surface on which a reducing species reacts with least one oxidizing species present in the high temperature water. The concentration of the oxidizing species is reduced by reaction with the reducing species on the catalytic surface, thereby reducing the electrochemical corrosion potential of the component.

An isotope production system that includes a cyclotron having a magnet yoke that surrounds an acceleration chamber. The cyclotron is configured to direct a particle beam from the acceleration chamber through the magnet yoke. The isotope production system also includes a target system that is located proximate to the magnet yoke. The target system is configured to hold a target material and includes a radiation shield that extends between the magnet yoke and the target location. The radiation shield is sized and shaped to attenuate gamma rays emitted from the target material toward the magnet yoke. The isotope production system also includes a beam passage that extends from the acceleration chamber to the target location. The beam passage is at least partially formed by the magnet yoke and the radiation shield of the target system.

A method for determining a fresh fuel bundle design for a core of a nuclear reactor may include defining a plurality of inputs including user-defined target conditions for evaluating one or more reference fresh fuel bundle designs for each of N bundle groups, and generating a response surface based on making single rod-type changes in each (i,j) rod location of each bundle of a given reference bundle design being evaluated for each of the N bundle groups. A search algorithm may be iterated to evaluate a given combination of multiple rod-type changes made simultaneously across each of the N bundle groups using the generated response surface to determine an accepted fuel bundle design for each of the N bundle groups that satisfies the user-defined target conditions.

A canister apparatus, basket apparatus and combinations thereof for transporting and / or storing high level radioactive waste, such as spent nuclear fuel. The canister apparatus comprises a cavity for receiving the spent nuclear fuel that is surrounded by two independent gas-tight containment boundaries. The structures that form the two independent gas-tight containment boundaries are in substantially continuous surface contact with one another, thereby facilitating sufficient heat removal from the cavity. In another aspect, the invention is a basket apparatus having a plurality of disk-like grates arranged in a stacked and spaced arrangement so that the cells of the disk-like grates are aligned. In still another aspect, the invention can be a basket apparatus having a disk-like grate having a ring-like structure encompassing a gridwork of beams specially arranged to achieve a unique cell configuration.

The invention relates to an installing method for a main pipeline of a coolant system of a nuclear power station, which is characterized in that the main pipeline of the coolant system of a reactor of the pressurized water reactor nuclear power station comprises a cool section (41) and a hot section (42), and a steam generator is directly connected with a main pump. According to the invention, the problem that the main pipeline is installed and welded by only a pressure container or steam generator in place by adopting the installing method of the main pipeline without a transition section issolved, and technical limit that the main pipeline is installed after the pressure container is in place and the steam generator or main pump is in place in the traditional main pipeline constructiontechnology is eliminated. A main pipeline groove is processed by adopting a site numerical control machining technology, the main pipeline and equipment connected with the main pipeline are subjectedto measurement, modeling and process monitoring by adopting a laser tracking measuring and 3D modeling technology, the main pipeline is regulated to meet the assembly welding requirement and is installed by using a narrow TIG (argon tungsten-arc welding) automatic welding technology, thus a feasible method is provided for shortening the construction period of the nuclear power station.

A plurality of grooves is formed on a radiating surface side of band-like members constituting an outer casing of a cask. By the grooves, radiating fins are formed on the radiating surface side of the band-like member and the like. Heat transfer fins are respectively welded to the opposite sides of the band-like member, leaving the opposite edges thereof. The heat transfer fins are welded to buildup portions on the surface of a trunk body. The band-like member and the heat transfer fins form a unit with a U-shaped cross-section, and the units are welded on the surface of the trunk body at a predetermined interval. A step portion is respectively formed at the opposite edges of the band-like member, and a step portion of the band-like member is fitted to the step portion, and welded.

A system, apparatus and method of processing and / or removing radioactive materials from a body of water that utilizes the buoyancy of the water itself to minimize the load experienced by a crane and / or other lifting equipment. In one aspect, the invention is a method comprising: a) submerging a container having a top, a bottom, and a cavity in a body of water having a surface level, the cavity filling with water; b) positioning radioactive material within the cavity of the submerged container; c) raising the submerged container until the top of the containment apparatus is above the surface level of the body of water while a major portion of the container remains below the surface level of the body of water; and d) removing bulk water from the cavity while the top of the container remains above the surface level of the body of water and a portion of the container remains submerged. The bulk water can be added back into the cavity to add neutron shielding after the container is placed in a staging area and prior to personnel performing the desired operations to the container. As a result, gamma radiation and neutron shielding of the container can be maximized for any crane capacity.

A combinatorial heterogeneous-homogeneous reactor configuration in which an array or groups of homogeneous fuel assemblies are interlinked together in a heterogeneous lattice. The present invention removes the limitation of a homogeneous reactor by providing a reactor concept that utilizes the inherent advantages of homogeneous fuel elements but in a heterogeneous fuel lattice arrangement that limits the power density of any one homogeneous fuel element and yet forms a reactor arrangement that is capable of producing any product demand of interest. The present invention provides a method for producing medical isotopes by the use of a modular reactor core comprised of homogeneous fuel assemblies arranged in a regular rectangular or triangular pitch lattice. The aqueous fuel solution is contained within individual fuel assemblies that are right circular cylinders clad in corrosion-resistant alloys such as stainless steel, zircalloy, zircalloy alloys, or other metal alloys that are resistant to corrosive fissile environments but preserve neutron economy. The fuel assemblies are supported below by a core plate that is tied directly to the lower reactor support structure. The bottom of each assembly opens into a common plenum area which provides a hydrodynamic communication / coupling path between the individual assemblies in the lattice. The fuel assemblies are supported above by an upper plate that is welded to each assembly tube. The top of each assembly opens to a common upper plenum which provides a means of thermodynamic pressure equalization among the four assemblies in the reactor core lattice.

A clamp apparatus is provided which is designed to structurally replace a weld that attaches a riser brace assembly to a reactor vessel wall, and to stiffen the entire riser brace assembly, thereby increasing the natural vibration frequency of the riser brace assembly. Installation of the clamp apparatus should not require removal of any installed reactor hardware, such as jet pump assembly hardware or shroud repair hardware. In an embodiment, the clamp apparatus may include a first plate arranged so as to mate with a first groove on the riser brace, and a second plate arranged so as to mate with a second groove on the riser brace. The grooves provide alignment for the clamp apparatus, so that the first and second plates can be fixedly secured to the riser brace.

A method is described herein for coating the substrate of a component for use in a water cooled nuclear reactor to provide a barrier against corrosion. The method includes providing a zirconium alloy substrate; and coating the substrate with particles selected from the group consisting of metal oxides, metal nitrides, FeCrAl, FeCrAlY, and high entropy alloys. Depending on the metal alloy chosen for the coating material, a cold spray or a plasma arc spray process may be employed for depositing various particles onto the substrate. An interlayer of a different material, such as a Mo, Nb, Ta, or W transition metal or a high entropy alloy, may be positioned in between the Zr-alloy substrate and corrosion barrier layer.

Example embodiments are directed to methods of producing desired isotopes in commercial nuclear reactors and associated apparatuses using instrumentation tubes conventionally found in nuclear reactor vessels to expose irradiation targets to neutron flux found in the operating nuclear reactor. Example embodiments include assemblies for retention and producing radioisotopes in nuclear reactors and instrumentation tubes thereof. Example embodiments include one or more retention assemblies that contain one or more irradiation targets and are useable with example delivery systems that permit delivery of irradiation targets. Example embodiments may be sized, shaped, fabricated, and otherwise configured to successfully move through example delivery systems and conventional instrumentation tubes while containing irradiation targets and desired isotopes produced therefrom.