Abstract: An elongate fuel element is described that has a silicon carbide cladding enclosing a fuel, such as UO2, wherein the fuel is dimensioned relative to the cladding to define gaps at each lateral end of the enclosure sufficiently large such that upon swelling in use, the fuel does not increase the strain on the cladding beyond the limits of the claddings strain tolerance. The lateral gaps at the ends of the fuel allow lateral expansion during swelling that reduces the strain on the cladding.

Abstract: An igniter apparatus which generates a high speed buoyancy induced vortex to funnel hydrogen and air from the surrounding onto the “igniter core” where an “igniter core” heats up to the auto ignition temperature by the exothermic catalytic oxidation of hydrogen on its surface. Water (vapor) is formed as the product, which inhibits the oxidation reaction, if not stripped away from the catalyst surface. The high velocity of the vortex ensures the stripping of the boundary layer of steam that is formed by the reaction, thus ensuring more active sites are available for hydrogen oxidation. The vortex is formed by channeling an upward draft into a vortex by guided fins. The upward draft is formed by a plate, which is also coated with a hydrogen recombination catalyst. The plate becomes hot by the same catalytic oxidation reaction in the presence of air containing hydrogen.

Abstract: A coupler for connecting an irradiation target assembly to a transfer system is provided. The coupler comprises a housing and an inner assembly. The housing comprises a distal end, a proximal end and a side section defining a cavity therein. The side section comprises a plurality of side bores extending into the cavity. The inner assembly comprises an actuator body, a return member for exerting a default axial force on the actuator body, and a plurality of friction members configured to be transversely driven by the actuator body through the plurality of side bores. The actuator body is positioned within the cavity and comprises a first section, a second section and a middle section. A coupling system comprising a coupling insert for a transfer system and a coupler for an irradiation target assembly are also provided.

Abstract: A detection apparatus includes a resonant electrical circuit supported within an interior of a nuclear fuel rod generates a response pulse in response to an excitation pulse and transmits the response pulse through a cladding of the fuel rod to another location within a reactor in which the fuel rod is housed and without any breach in the cladding. A characteristic of the response pulse is indicative of a condition of the fuel rod. The detection apparatus also includes a transmitter positioned outside the cladding, in the reactor, in the vicinity of the fuel rod and configured to generate the excitation pulse and transmit the excitation pulse through the cladding to the resonant electrical circuit. A receiver is supported within the reactor outside of the cladding and, in response to the response pulse, communicates a signal to an electronic processing apparatus outside of the reactor.

Abstract: The systems and methods of the invention pertain to analyzing steam generator tube data for the detection of wear. Further, the invention is capable of performing a comparison of current tube signal data to baseline or historic tube signal data, e.g., from previous and/or the first, in-service inspection of the steam generator. The systems and methods are automated and can generate results to show potential tube-to-tube contact wear areas as well as the progression of tube-to-tube gap reduction within a steam generator tube bundle. In certain embodiments, the invention is capable of comparing current and historical eddy current data to determine the difference that may be related to degradation or other interested phenomena, and of processing and trending historical comparison results to establish normal variance and detect abnormal variances.

Abstract: A portable real-time system monitoring device is advantageously capable of autonomously learning the normal behavior of any system and of alerting the user or taking other action when the system becomes unpredictable or otherwise undesirable. No prior knowledge about the system is needed by the device. This is because the device uses a combination of machine learning and statistical process control to autonomously develop its own model of the monitored system and then autonomously monitor the system for unexpected behavior. Therefore, without any prior analysis or model creation, it can be deployed on any system, and it can be reused on any other system after it has been reset. The advantageous device of the disclosed and claimed concept performs this function in either real time or near real-time.

Abstract: Provided herein is a nuclear fuel assembly for a pressurized water reactor. The nuclear fuel assembly comprises: a plurality of nuclear fuel rods configured to contain a fissile material, wherein the nuclear fuel assembly is configured such that a hydrogen to uranium ratio for the fuel assembly, when coolant and the fissile material are present under operating conditions, is at least 4.0. Also provided herein is a method for refueling a pressurized water nuclear reactor comprising a nuclear fuel assembly of the present disclosure.

Abstract: A housing assembly configured to house a reactor is disclosed. The housing assembly includes a plurality of modular walls configured to surround the reactor and a passive temperature control system. The plurality of modular walls includes a first modular wall. The passive temperature control system is coupled to the first modular wall. The passive temperature control system is configured to transfer heat between the reactor and an area around the housing assembly.

Abstract: Disclosed is a video processor for removing interference due to nuclear radiation. The video processor includes a control circuit configured to receive video data from a camera placed in a nuclear radioactive environment, determine a first image from the video data, calculate a first brightness value at a first pixel in a first pixel location in the first image, determine a second image from the video data, calculate a second brightness value at a second pixel in a second pixel location in the second image, compare the first brightness value to the second brightness value, and update the second image by replacing the second pixel in the second image with the first pixel when the second brightness value is greater than the first brightness value. The first image corresponds to a time before the second image, and the first pixel location and the second pixel location are the same location.

Abstract: A forming assembly configured to form a wick is disclosed. The forming assembly includes an expandable tube and a forming shell assembly. The expandable tube is hydraulically expandable to an expanded configuration. A wick mesh is configured to be wrapped about the expandable tube. The forming shell assembly includes a first forming shell comprising a first recess defined therein and a second forming shell comprising a second recess defined therein. The first recess and the second recess cooperate to define an outer diameter of the wick. The expandable tube and the wick mesh are positionable between the first recess and the second recess. The expandable tube and the forming shell assembly are configured to deform the wick mesh and form the wick based on the expandable tube hydraulically expanding towards the expanded configuration.

Abstract: A nuclear instrumentation and control system is disclosed herein. The nuclear instrumentation and control system can include a housing and a plurality of selectively removable finished board assemblies configured to be installed within the hosing and electrically coupled to the instrumentation and control system nuclear reactor. At least one of the selectively removable finished board assemblies includes an input/output circuit. The nuclear instrumentation and control system can further include a daughter card including a control circuit, wherein the daughter card is configured to be selectively coupled to the at least one selectively removable base board of the plurality of selectively removable base boards via a mechanical connector and an electrical connector.

Abstract: A power sensor system for monitoring a subcritical neutron generator is provided. The power sensor system comprises a self-powered sensor insert. The self-powered sensor insert comprises an insert thimble and a detector assembly. The insert thimble includes an outer housing, a power generator configured to produce an electrical power based on an incident radiation and a first electrical interface electrically connected to the power generator. The detector assembly includes a solid state radiation detector able to provide a detector signal directly proportional to a neutron flux level, a transmitter configured to wirelessly output a transmitter signal based on the detector signal and a second electrical interface configured to electrically couple to the first electrical interface. A power monitor system comprising a power sensor system and a control system and a method for optimizing a subcritical neutron generator are also provided.

Abstract: A method of releasing an atmospheric effluent within a nuclear containment to an atmosphere surrounding the nuclear containment is disclosed. The nuclear containment is adjacent to an associated spent fuel pool that is located outside the nuclear containment, the method comprises sensing a pressure buildup within the nuclear containment, routing a portion of the atmospheric effluent through the spent fuel pool when a pressure buildup within the nuclear containment reaches a preselected value, and releasing a chemical into the spent fuel pool, based on the routing, to facilitate a reaction with the atmospheric effluent to substantially neuter any deleterious environmental impact of the atmospheric effluent.

Abstract: The invention relates to a multi-component cladding for a nuclear fuel rod that includes a combination of ceramic and metal components. More particularly, the invention is directed to a cladding that includes a ceramic composite having a zirconium composition deposited thereon to form a zirconium coated ceramic composite. The ceramic composite includes a ceramic matrix and a plurality of ceramic fibers. The cladding is effective to protect the contents of the cladding structure from exposure to high temperature environments during various load conditions of a nuclear reactor.

Abstract: Disclosed is an apparatus, system, and method for monitoring a position of a control rod disposed in a nuclear reactor vessel in a radioactive environment. A data processing unit located outside a containment structure includes a processor and a memory storing executable instructions. A nuclear reactor vessel includes a plurality of control rods proximate to the control rod and a coil stack of a plurality of control rod position indicator coils. A data cabinet mounted on the nuclear reactor vessel head inside the containment structure includes an analog multiplexer and a communication circuit. The processor executes the instructions to select a control rod position indicator coil through the analog multiplexer, pass a signal from the control rod position indicator coil through the analog multiplexer, receive the signal from the analog multiplexer through the communication circuit, and determine a position of the control rod based on the received signal.

Abstract: A method of forming a wick assembly is disclosed including positioning an inner ring in a first wick, positioning the inner ring in a second wick, abutting an end of the first wick with an end of the second wick, positioning an outer ring about a portion of the first wick and a portion of the second wick, positioning a mandrel within the inner ring, positioning a die about the outer ring, and applying a force to the die, wherein the force couples the outer ring, the inner ring, the first wick, and the second wick together to form the wick assembly.

Abstract: A target irradiation apparatus for producing radioisotope sources is provided. The target irradiation apparatus comprises a containment vessel, a plurality of electronic neutron generator inserts and a removable neutron enhancement cartridge. The containment vessel comprises an inner surface, an outer surface, a first end, a second end, a body section, and a support member. Each of the plurality of electronic neutron generator insert devices is inserted into one of a plurality of openings of the body section while the removable neutron enhancement cartridge is adapted to be positioned inside of the containment vessel. A radioisotope production system comprising a target irradiation apparatus and a method for producing radioisotope sources are also provided.

Abstract: An in-core detector configured to measure a power distribution in a nuclear reactor is disclosed herein. The in-core detector includes a housing configured to be placed within a predetermined location of the nuclear reactor and a plurality of a gamma detectors. Each gamma detector of the plurality of gamma detectors includes a Schottky diode including an active semiconductor region and a Schottky contact, an Ohmic contact, a photoelectron source material configured to transfer electrons to the active region upon contact with gamma radiation, and a first and second lead. The plurality of gamma detectors are positioned within the housing such that each gamma detector of the plurality of gamma detectors is radially offset relative to an adjacent gamma detector of the plurality of gamma detectors, such that the first and second leads of each gamma detector are offset relative to the first and second leads of the adjacent gamma detector.

Abstract: The invention relates to methods for protecting a nuclear reactor core, such as a boiling water reactor core, from fuel and cladding damage due to thermal hydraulic instability in extended operating power flow conditions and, in particular, when an extended power uprate is implemented. The methods employ existing licensed stability methodologies and incorporated minor changes, e.g., to the Average Power Range Monitor (APRM)-based trip system to preclude operation inside the stability vulnerable region of the power/flow map. The APRM-based trip system is modified to set down the APRM flow-biased scram line when core flow is less than a predetermined core flow to prevent the core from entering an unstable region of operation.

Abstract: A nuclear reactor is disclosed including a reactor core and a reflector assembly surrounding the reactor core. The reflector assembly includes a stationary reflector component including a graphite support structure comprising a plurality of channels defined therein and a plurality of beryllium-oxide pins positioned in the channels.