1326results about "Nuclear engineering problems" patented technology

Compositions and processes for forming radiopaque polymeric articles are disclosed. In one embodiment, radiation inspection apparatuses and methods are then used to determine the presence and attributes of such radiopaque polymeric articles. A radiopaque polymeric article of the present invention can be created by mixing a radiopaque material, such as barium, bismuth, tungsten or their compounds, with a powdered polymer, pelletized polymer or liquid solution, emulsion or suspension of a polymer in solvent or water. In addition to creating radiation detectable objects, the radiopaque polymeric materials of the present invention can be used to create radiation protective articles, such as radiation protective garments and bomb containment vessels. Enhanced radiation protection can also be achieved through the use of nano-materials. The principals of the present invention can be used to provide protection against other types of hazards, including fire, chemical, biological and projectile hazards.

A method and apparatus for transporting syringes containing radioactive material. The apparatus includes a radiopharmaceutical pig having an inner chamber in which a sharps container can be secured. The sharps container has a housing and an attachable cap. The method includes assembling the radiopharmaceutical pig so that the chamber of the radiopharmaceutical pig contains the syringe in the sharps container housing. The radiopharmaceutical pig is disassembled, where upon the syringe is removed, discharged, and then replaced in the sharps container housing. The cap of the sharps container is affixed to the housing of the sharps container, thus enclosing the contaminated syringe therein. The radiopharmaceutical pig is assembled so that its chamber contains the sharps container and the syringe. The radiopharmaceutical pig is transported to a disposal area, where it is disassembled and the sharps container containing the syringe is placed in a particular disposal container.

A rod assembly for a fuel bundle of a nuclear reactor may include an upper end piece, lower end piece and a plurality of rod segments attached between the upper and lower end pieces and to each other so as to form an axial length of the rod assembly. The rod assembly may include an adaptor subassembly provided at given connection points for connecting adjacent rod segments or a given rod segment with one of the upper and lower end pieces. The connection points along the axial length of the rod assembly may be located where the rod assembly contacts a spacer in the fuel bundle. One (or more) of the rod segments may include an irradiation target therein for producing a desired isotope when a fuel bundle containing one (or more) rod assemblies is irradiated in a core of the reactor.

A containment vessel includes a primary containment vessel containing a reactor pressure vessel, an upper secondary containment vessel arranged above the primary containment vessel, and a gas-phase vent pipe linking the primary containment vessel and the upper secondary containment vessel by way of an isolation and connection switching system. The gas-phase vent pipe may be arranged either inside or outside the primary containment vessel and the upper secondary containment vessel. Alternatively, it may be embedded in the wall. An igniter may be arranged in the upper secondary containment vessel. The air in the upper secondary containment vessel may be replaced by nitrogen. A gravity-driven flooding system pool may be arranged in the upper secondary containment vessel and cooling water may be led from the inside of the pool to the inside of the primary containment vessel.

A multi-layered ceramic tube having an inner layer of high purity beta phase stoichiometric silicon carbide, a central composite layer of continuous beta phase stoichiometric silicon carbide fibers, and an outer layer of fine-grained silicon carbide. The ceramic tube is particularly suited for use as cladding for a fuel rod used in a power plant or reactor. The ceramic tube has a desirable combination of high initial crack resistance, stiffness, ultimate strength, and impact and thermal shock resistance.

A nuclear-powered plant for systems of up to about 100 MWs with a confinement section where the reaction takes place in a core having a reactive thorium / uranium-233 composition, and where an external neutron source is used as a modulated neutron multiplier for the reactor core output. The core is housed in a containment structure that radiates thermal energy captured in a multiple-paths heat exchanger. The exchanger heat energy output is put to use in a conventional gas-to-water heat exchanger to produce commercial quality steam.

A power module assembly includes a reactor vessel containing a reactor core surrounded by a primary coolant. A containment vessel is adapted to be submerged in a containment cooling pool and to prohibit a release of the primary coolant outside of the containment vessel. A secondary cooling system is configured to remove heat generated by the reactor core. The heat is removed by circulating liquid from the containment cooling pool through the primary coolant.

Articles, including fabrics and film layers, are disclosed which can protect against multiple hazards, including radiation, chemical, biological agents, metal projectiles and fire hazards. In some embodiments, the fabrics and films of the present invention are used to produce garments having protection against multiple hazards and superior heat dissipating properties. A radiation protective compound is preferably created by mixing a radiopaque material, such as barium, bismuth, tungsten or their compounds, with powdered polymer, pelletized polymer or a liquid solution, emulsion or suspension of a polymer in solvent or water. This radiation protective mixture can then be laminated or otherwise adhered to other types of protective films or fabric, such as the protective polymer films or fabrics used for chemical protective garments, biological protective garments, bullet proof vests or fire retardant garments. The principles of this invention can also be applied to a broad range of other articles including surgical hoods, hospital gowns, gloves, patient drapes, partitions, coverings, jumpsuits, ponchos, uniforms, fatigues, tents, probes, envelopes, pouches, wallpaper, liners, drywall, house sidings, house foundations, house roofings etc.

A support grid for a nuclear fuel assembly, the fuel rod assembly having a generally cylindrical fuel rod with a diameter, wherein the support grid includes a frame assembly having a plurality of generally uniform cells, each the cell having at least one wall and a width and at least one generally cylindrical tubular member having a cell contact portion with a greater diameter and at least one helical fuel rod contact portion with a lesser diameter, the cell contact portion and the fuel rod contact portion joined by a transition portion, the greater diameter being generally equivalent to the cell width, and the lesser diameter being generally equivalent to the fuel rod diameter such that a fuel rod disposed in the tubular member would engage the inner diameter. Wherein the least one tubular member disposed in one cell of the plurality of generally square cells so that the cell contact portion engages the at least one cell sidewall.

A pharmaceutical pig is used to transport a syringe containing a liquid radiopharmaceutical from a radiopharmacy to a medical facility for administration to a patient. The used syringe is sent back in the pig to the radiopharmacy for disposal. The pig includes a cap that is removably attached to a base. Shielding elements, typically formed from lead, are enclosed in the cap and the base. The pig can be used to transport a conventional syringe or a safety syringe. The pig can be used with or without an inner liner in the base. There is never an inner liner in the cap.

An In Orbit Transportation & Recovery System (IOSTAR™) (10) One preferred embodiment of the present invention comprises a space tug powered by a nuclear reactor (19). The IOSTAR™ includes a collapsible boom (11) connected at one end to a propellant tank (13) which stores fuel for an electric propulsion system (12). This end of the boom (11) is equipped with docking hardware (14) that is able to grasp and hold a satellite (15) and as a means to refill the tank (13). Radiator panels (16) mounted on the boom (11) dissipate heat from the reactor (19). A radiation shield (20) is situated next to the reactor (19) to protect the satellite payload (15) at the far end of the boom (11). The IOSTAR™ (10) will be capable of accomplishing rendezvous and docking maneuvers which will enable it to move spacecraft between a low Earth parking orbit and positions in higher orbits or to other locations in our Solar System.

A motorized bracelet assembly for ultrasonic crack detection in a pipe. The bracelet has a motorized frame adapted for installation around the pipe and a sliding arrangement slideably mounted onto the frame. The sliding arrangement guides a displacement of sensor modules in periphery of the pipe. A first driving device controllably drives the sliding arrangement and thereby displacing the sensor modules in periphery of the pipe at desired operating positions. The bracelet comprises biasing devices for biasing the sensor modules against the pipe and a second driving device for controllably driving the frame along the axial direction of the pipe at a desired operating position.

This invention deals with multi-component composite materials and techniques for improved shielding of neutron and gamma radiation emitting from transuranic, high-level and low-level radioactive wastes. Selective naturally occurring mineral materials are utilized to formulate, in various proportions, multi-component composite materials. Such materials are enriched with atoms that provide a substantial cumulative absorptive capacity to absorb or shield neutron and gamma radiation of variable fluxes and energies. The use of naturally occurring minerals in synergistic combination with formulated modified cement grout matrix, polymer modified asphaltene and maltene grout matrix, and polymer modified polyurethane foam grout matrix provide the radiation shielding product. These grout matrices are used as carriers for the radiation shielding composite materials and offer desired engineering and thermal attributes for various radiation management applications.

A remotely controlled apparatus (112) for inspecting the core (102) and annulus (104) areas of nuclear boiling water reactors (100) includes a circumferential drive mechanism for propelling the apparatus (112) on the steam dam (108) of the reactor (100). The inspection apparatus (112) uses a set of driver rollers (314) that grip the side of the steam dam (108) and provide propulsion for the apparatus. A pinch-roller assembly with high-tension springs (308) and pneumatic air cylinders (310) is utilized for removably securing a set of pinch rollers (312) to the side of the steam dam opposite the side of the driver rollers (314). A set of rollers (304) are adapted to rest on top of the steam dam (108), supporting the weight of the apparatus (112) and enabling the apparatus to move around the steam dam (108). Two positioning guide rails (306) aid in the balance of the apparatus (112), especially when it is stationary. The apparatus (112) has a watertight main body (202), which houses the electrical control wiring and circuitry. The main body (202) has a front camera (204) and a rear camera (205) used to direct the movements of the apparatus (112). The main body also has two turret-type telescoping mast assemblies (208) with telescoping masts 210 and 212, which are capable of extending at a selected distance above and below the main body (202). The mast assemblies 210 and 212 support inspection equipment such as radiation-shielded EVT-1-capable video cameras and radiation-tolerant fiberscopes. The apparatus (112) and its inspection tools are remotely controlled via control consoles with video monitors from a low-dose, non-contaminated enclosure located remotely from a boiling water reactor.

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.

In one embodiment, a method for detecting contaminants in a liquid comprises: contacting a sensor with a liquid, generating electrical information based upon a concentration of the contaminant in the liquid, transmitting the electrical information to a controller, and determining the concentration of a contaminant in the liquid. The sensor can comprise a film, a purge chamber, and a transducer, which are configured such that a first surface of the film is in fluid communication with the liquid and the purge chamber is in fluid communication with a second surface of the film that is opposite the first surface, and wherein the transducer is in fluid communication with the purge chamber.

Techniques and compositions are provided for shielding radioactive energy. The composition includes a hydrocarbon component and a radiation shielding and absorbing material or additive. The composition may be applied to substrates or to radioactive materials. Moreover, the composition may be mixed with raw materials of products.

A system includes a containment vessel configured to prohibit a release of a coolant, and a reactor vessel mounted inside the containment vessel. An outer surface of the reactor vessel is exposed to below atmospheric pressure, wherein substantially all gases are evacuated from within the containment vessel.

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.

A fast reactor having a reflector control system is provided which decreases the change in reactivity of the reactor core with time without performing control of a reflector lifting speed and that of a water flow rate. The above fast reactor has a liquid metal coolant, a reactor core immersed therein, and a neutron reflector which is provided outside the reactor core and which is moved in a vertical direction for adjusting leakage of neutrons therefrom for controlling the reactivity of the reactor core. The neutron reflector described above is gradually moved in an upward direction with the change in reactivity caused by fuel burn-up, and at least a part of a lower region of the neutron reflector is a high reflection region having a high neutron reflection ability as compared to that of the other region. The high reflection region is located from the bottom to a place between one fourth and one half of the height of the neutron reflector from the bottom end thereof.

A bismuth compound composite having a polymer matrix and a bismuth compound therein. The bismuth compound may be bismuth oxide, or other bismuth compounds. The polymer may be any of a very wide range of materials or combinations thereof. Binder, secondary fillers or other third components may be added. By means of use of various bismuth compounds, polymers, and third components, the physical, radiological and electrical properties of the finished products may be tailored to achieve desired properties. In addition, the invention teaches that radiation shielding, insulators, and combined radiation shield / insulators may be fashioned from the composite. A wide range of production methods may be employed, including but not limited to liquid resin casting.

A nuclear fuel element includes a core formed from a high density solid solution fissile material that is substantially free of carbon and void space. A cladding substantially surrounds the core.

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.

In the method for reactor simulation, a user modifies one or more design inputs used in creating a response surface. The response surface defines relationships between the design inputs and operational outputs of at least one or more aspects of a core design. A reactor simulation is then generated based on the response surface for the core design and the modified design input.