Abstract: A pressurized water reactor (PWR) includes a vertical cylindrical pressure vessel having a lower portion containing a nuclear reactor core and a vessel head defining an integral pressurizer. A reactor coolant pump (RCP) mounted on the vessel head includes an impeller inside the pressure vessel, a pump motor outside the pressure vessel, and a vertical drive shaft connecting the motor and impeller. The drive shaft does not pass through the integral pressurizer. The drive shaft passes through a vessel penetration of the pressure vessel that is at least large enough for the impeller to pass through.

Abstract: A target apparatus for a radioisotope production system. The target apparatus includes a production chamber that is configured to contain a starting liquid. The production chamber is configured to receive a particle beam that is incident upon the starting liquid thereby generating radioisotopes and transforming a portion of the starting liquid into vapor. The target apparatus also includes a condensing chamber and a fluid channel that fluidly couples the production and condensing chambers and is configured to allow the vapor to flow from the production chamber to the condensing chamber. The condensing chamber is configured to transform the vapor into a condensed liquid.

Abstract: 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.

Abstract: A pressurized water reactor vessel having a flow skirt formed from a perforated cylinder structure supported in the lower reactor vessel head at the outlet of the downcomer annulus, that channels the coolant flow through flow holes in the wall of the cylinder structure. The flow skirt is supported at a plurality of circumferentially spaced locations on the lower reactor vessel head that are not equally spaced or vertically aligned with the core barrel attachment points, and the flow skirt employs a unique arrangement of hole patterns that assure a substantially balanced pressure and flow of the coolant over the entire underside of the lower core support plate.

Abstract: An advanced initial core fuel configuration is for improving the fuel management efficiency and thus economics for a nuclear reactor. A method of implementing such an initial core involves providing a plurality of fuel assemblies having different average enrichments of uranium 235 and arranging the fuel assemblies in an initial core configuration structured to emulate a known equilibrium reload cycle core at least in terms of spatial reactivity distribution. The resulting average enrichment within the initial core ranges from below about 1.0 percent weight of uranium 235 to about 5.0 percent weight of uranium 235. An advanced lattice design is also disclosed.

Abstract: Fuel assemblies include an outer channel having a physical configuration optimized for a position of the fuel assembly within a core of a nuclear reactor. The position of the fuel assembly with respect to an employed control blade in the nuclear reactor determines if the outer channel may be thickened, reinforced, and/or fabricated of Zircaloy-4 or similar distortion-resistant material, so as to reduce or prevent distortion of the channel against the control blade, or thinned so as to increase water volume and enhance reactivity in the assembly. Reactor cores having configured fuel assemblies include fuel assemblies having different outer channels. Methods include determining operational characteristics of the fuel assembly, including likelihood of being placed directly adjacent to an employed control blade, and physically selecting or modifying the outer channel of the fuel assembly based thereon.

Abstract: Cylindrical inertial confinement fusion reaction chambers are disclosed according to some embodiments of the invention. These chambers can include neutron moderating/absorbing material, radiation absorbing material, and debris collection material. These chambers can also include various injection ports, nozzles, beam ports, sacrificial layers, absorbers, coolant systems, etc. These chambers can be used with directional and/or omni-directional targets.

Abstract: In a nuclear installation, an instrument includes a sensor module connected to a process flange. The sensor module includes a support conduit with support conduit threads. An electronic circuit is wired to a connector that includes a key that is aligned with field circuit contacts of the connector. A thermal and nuclear radiation shield encloses the electronic circuit and includes a shock protection annulus. The connector is secured inside the shock protection annulus. The thermal and nuclear radiation shield includes shield threads that rotatably engage the support conduit threads to rotate an alignment of the key relative to the process flange.

Abstract: A traveling wave nuclear fission reactor, fuel assembly, and a method of controlling burnup therein. In a traveling wave nuclear fission reactor, a nuclear fission reactor fuel assembly comprises a plurality of nuclear fission fuel rods that are exposed to a deflagration wave burnfront that, in turn, travels through the fuel rods. The excess reactivity is controlled by a plurality of movable neutron absorber structures that are selectively inserted into and withdrawn from the fuel assembly in order to control the excess reactivity and thus the location, speed and shape of the burnfront. Controlling location, speed and shape of the burnfront manages neutron fluence seen by fuel assembly structural materials in order to reduce risk of temperature and irradiation damage to the structural materials.

Abstract: Illustrative embodiments provide modular nuclear fission deflagration wave reactors and methods for their operation. Illustrative embodiments and aspects include, without limitation, modular nuclear fission deflagration wave reactors, modular nuclear fission deflagration wave reactor modules, methods of operating a modular nuclear fission deflagration wave reactor, and the like.

Abstract: A grid including at least two meshed grid parts intended to be superposed in a longitudinal direction, each grid part extending in a transverse plane, and the grid parts being moveable one relative to the other in at least one transverse direction between an open configuration for the insertion of nuclear fuel rods in the longitudinal direction through the grid parts, and a closed configuration allowing each fuel rod inserted through the grid parts to be clamped transversely between the grid parts. According to one aspect of the invention, the grid includes elements for transversely immobilizing the grid parts in the closed configuration, the immobilizing elements being designed to engage as the superposed grid parts are moved closer together in the longitudinal direction.

Abstract: Apparatus for longitudinally segmenting a cruciform shaped irradiated boiling water reactor control rod having four elongated blades radially extending from a central spline, into four flat panels. The apparatus employs a double bladed band saw with the band saw blades orthogonally oriented at two different elevations and having one side of each band saw blade crossing over the center of the spline of the control rod in between the control rod blades.

Abstract: A method and system for detecting special nuclear materials are disclosed. Said method and system detect the special nuclear materials by making use of the photofission characteristic and thermal neutron induced fission characteristic thereof. In one preferred embodiment, the high density and/or high atomic number region in the object to be detected is also detected first as a suspicious region.

Abstract: Isotope production system including a particle accelerator configured to produce a particle beam. The isotope production system also includes a target apparatus having a window configured to receive a particle beam and also separate production and condensing chambers. The production chamber is configured to contain a starting liquid and located so that the particle beam is incident upon the starting liquid thereby generating radioisotopes and transforming a portion of the starting liquid into vapor. The target apparatus also includes a fluid channel that extends between and fluidly couples the production and condensing chambers. The fluid channel is configured to allow the vapor to flow from the production chamber into the condensing chamber. The condensing chamber is configured to transform the vapor in the condensing chamber into a condensed liquid.

Abstract: Embodiments of systems and methods for compressing plasma are disclosed in which plasma can be compressed by impact of a projectile on a magnetized plasma in a liquid metal cavity. The projectile can melt in the liquid metal cavity, and liquid metal may be recycled to form new projectiles.

Abstract: A system for monitoring a state of a reactor core in a nuclear reactor may include an internal monitoring device located inside the reactor core, the internal monitoring device including one or more internal sensor arrays configured to take measurements of conditions of the reactor core at different vertical regions within the reactor core to generate internal measurement data; an external monitoring device located in the reactor structure outside the reactor core, the external monitoring device including one or more external sensor arrays configured to take measurements of conditions of the reactor core at positions outside the reactor core corresponding the plurality of different vertical regions within the reactor core to generate external measurement data, and a transmitter configured to wirelessly transmit the external measurement data; and a receiver station configured to determine a state of the reactor core based on the external and internal measurement data.

Abstract: A fusion device produces fusion of neutral atoms and ions in an “aneutronic fusion” manner without neutrons as products utilizes strong ion-neutral coupling at high neutral densities. Ions and neutrals rotate together in a cylindrical chamber due to frequent collisions. High magnetic forces make the attainment of high rotation energy possible; the magnetic field in a medium can be set at very high values because of the absence of magnetic charges. The repeated acceleration by strong magnetic forces in the azimuthal direction makes possible very high ion velocity. Fusion takes place mainly between neutral particles. This approach can be applied to fusion with neutrons as well. Conventional fusion schemes and neutron sources can be realized using the principles described above in the generation of neutrals of high energies and densities.

Abstract: A system and method for reducing energetic proton flux trapped in the inner radiation belt by injecting Ultra Low Frequency (ULF) electromagnetic waves is disclosed. The ULF electromagnetic waves is generated by space or ground based transmitters and the frequency range is selected such that the injected waves are in gyrofrequency resonance with trapped 10 to 100 Mev protons. Pitch angle scattering of the trapped protons in gyro-resonance with the injected waves increases their precipitation rate by forcing their orbits into pitch angles inside the atmospheric loss-cone where they are lost by intaracting with the dense neutral atmosphere at altitudes below 100 km. The reduction of energetic proton flux trapped in the inner radiation belt allows use of commercial electronics with submicron feature size on Low Earth Orbit satellites and microsatellites without the operational constraints imposed by the presence of energetic proton fluxes trapped at the inner radiation belts.

Abstract: A method of manufacturing nuclear fuel elements comprising the steps of placing nuclear fuel balls in the container made from ultra-porous material, applying a CVI to the container and removing the container. The container for manufacturing fuel elements comprising balls, and is produced from at least one ultra-porous material, for example carbon foam.

Abstract: Systems and methods permit discriminate access to nuclear reactors. Systems provide penetration pathways to irradiation target loading and offloading systems, instrumentation systems, and other external systems at desired times, while limiting such access during undesired times. Systems use selection mechanisms that can be strategically positioned for space sharing to connect only desired systems to a reactor. Selection mechanisms include distinct paths, forks, diverters, turntables, and other types of selectors. Management methods with such systems permits use of the nuclear reactor and penetration pathways between different systems and functions, simultaneously and at only distinct desired times. Existing TIP drives and other known instrumentation and plant systems are useable with access management systems and methods, which can be used in any nuclear plant with access restrictions.