Abstract: A nuclear reactor facility may include a reactor building, a reactor vessel housed within the reactor building, and an auxiliary cooling system integrated with the reactor building. The reactor building has a visible section above a ground level and a buried section below the ground level. The reactor vessel contains a fuel core and is housed within the buried section of the reactor building below the ground level. The auxiliary cooling system includes a plurality of ducts integrated with the reactor building and is configured to passively cool the reactor vessel via natural air circulation.

Abstract: Systems enhance stand pipe alignment and security with braces docking to the stand pipes. A link connects pairs of braces so the braces and stand pipes docked thereby cannot move relative to each other when fully secured. Partially securing braces allows adjustment of the braces and distance between the same and thus stand pipe position. Fully securing the braces makes the entire system rigid without need for a tie bar. Braces and links can be installed and secured to the stand pipes and among each other at an axial position from above the stand pipes, so that overhead, simple tooling may be used. A crimp nut or other resilient connector may be used to secure the systems from that single dimension with simple tooling. Any number of braces, joining to any number of other braces, may be used in the system, and several systems may be used at various levels.

Abstract: A method of measuring moisture carryover (MCO) in a nuclear reactor includes placing a first gamma detector adjacent to a steam conduit configured to transport steam generated by the core. The method additionally includes detecting a first amount of carryover gamma activity of a first quantity of sodium-24 in the steam within the steam conduit with the first gamma detector. The method also includes detecting a second amount of reference gamma activity of a second quantity of sodium-24 in a reference sample of reactor water from the core with a second gamma detector. The method further includes determining a flow rate of liquid water entrained in the steam based on the first amount of carryover gamma activity detected by the first gamma detector and the second amount of reference gamma activity detected by the second gamma detector.

Abstract: A system, apparatus, method, and non-transitory computer readable medium for performing improved and/or optimal sensor placement may include a computing device caused to, receive a plurality of fault conditions and an initial sensor suite associated with at least one object to be simulated, the initial sensor suite including a plurality of candidate physical sensors for the at least one object, perform failure mode analysis of the initial sensor suite, the performing the failure mode analysis including generating at least one dependency-matrix (D-matrix) based on the plurality of fault conditions and the plurality of candidate physical sensors, and generate a recommended sensor suite associated with the at least one object based on results of the failure mode analysis, the recommended sensor suite including at least one recommended sensor, the at least one recommended sensor being a subset of the plurality of candidate physical sensors.

Abstract: An integrated nuclear-powered heat pump system includes a nuclear power plant including a nuclear reactor coolant and may be configured to generate electricity. The system additionally includes a heat pump including a refrigerant as a working fluid. The heat pump is integrated with the nuclear power plant so as to be in at least thermal contact with the nuclear reactor coolant. The electricity generated by the nuclear power plant may be used to drive the heat pump. The system is instrumental with regard to generating heat for industrial applications.

Abstract: A liquid metal-cooled nuclear reactor includes, within a reactor pressure vessel having a reactor core, a multistage annular linear induction pump (ALIP) configured to circulate liquid metal coolant through the reactor core. The multistage ALIP includes multiple sets of induction coils that at least partially define separate, respective stages of the multistage ALIP. The multiple sets of induction coils are configured to be electrically connected to separate, respective polyphase power supplies, such that the stages of the multistage ALIP are configured to be controlled independently of each other to adjustably control a flow of liquid metal coolant through the reactor core based on independent control of the multiple polyphase power supplies.

Abstract: A Modular Isolated Reactor Support System (MIRSS) assembly includes a cylindrical reactor support structure configured to structurally support a reactor enclosure system on seismic isolators, a collector cylinder configured to at least partially define a riser annulus between an inner cylindrical surface of the collector cylinder and an outer sidewall surface of the reactor enclosure system structurally supported by the cylindrical reactor support structure, and a divider wall configured to at least partially define a downcomer annulus between an outer cylindrical surface of the divider wall and a reactor building, and a plurality of exhaust ducts extending from the collector cylinder and through an interior of the cylindrical reactor support structure.

Abstract: The method includes generating first temperature data at a first temperature sensor based on a temperature of a first flowstream of a coolant fluid in a flow channel and heat transfer to the first temperature sensor from a heating element, the heating element being coupled to the first temperature sensor at an interface, the first temperature data indicating a first temperature measured by the first temperature sensor, generating second temperature data at a second temperature sensor based on a temperature of a second flowstream of the coolant fluid in the flow channel and independently of heat generated by the heating element, the first flowstream and the second flowstream running parallel to each other, the second temperature sensor being insulated from the heating element, the second temperature data indicating a second temperature measured by the second temperature sensor.

Abstract: A method of identifying at least one critical location on a physical structure includes receiving operational information related to an operation of the physical structure, the operational information including different time instances of the operation of the physical structure and the operation of the physical structure at different operational levels; predicting damage to the physical structure based on the operational information, predicted operation of the physical structure with at least one of the different operational levels, and at least one model of the physical structure such that initiation of the damage at a plurality of locations of the physical structure is predicted independent of a proximity of the sensors to each of the plurality of locations; and identifying the at least one critical location on the physical structure based on the predicted damage.

Abstract: A sodium-cooled nuclear reactor includes at least one electromagnetic pump assembly and a backflow reduction pipe. The backflow reduction pipe may include an inlet, an outlet, at least one tubular section having a first length and a first diameter, and at least one fluid diode section between the inlet and the outlet.

Abstract: Nozzles mix coolant from different sources together in an outlet to prevent differences in coolant output. Different flow path configurations are useable in the nozzle, including a multiple-path configuration with flows from different sources jacketed or concentrically arranged around flows from other sources. Swirl vanes may be installed in the nozzle to impart mixing or filtering the fluid flow. Diffusers may be used to passively suction or accelerate flow and mixing the same like a jet pump. Nozzles can be combined with filtration systems like trap filters that capture debris based on a momentum difference between the denser debris and fluid. Filters can use magnetic, adhesive, or porous materials to capture debris without blocking a flow path. Filters can be disengaged, such as when clogged, such that coolant flows around the system. Nozzles can be installed on feedwater sparger assemblies in varying manner to distribute coolant from multiple nozzles.

Abstract: The apparatus includes a flowmeter coupled a surface exposed to a flow channel. The flowmeter monitors a flow of coolant. The flowmeter includes a first temperature sensor that generates first temperature data based on measuring a first temperature of a first flowstream, a heating element coupled to the first temperature sensor where the heating element applies heat to the first temperature sensor through an interface, a second temperature sensor generates second temperature data based on measuring a second temperature of a second flowstream, the second temperature sensor being spaced apart from the heating element, and the second temperature sensor being at least partially insulated from the heating element so the second temperature data generated by the second temperature sensor is independent of heat generated by the heating element. A processor calculates a flowrate of the coolant based on the second temperature data and a temperature of the coolant fluid.

Abstract: Piping loops can carry either forced or natural circulation coolant flow from and back to a nuclear reactor depending on reactor and coolant state, and can transition between the two. The loop flows into a heat exchanger that cools the coolant and may even condense the coolant. The heat exchanger can drive natural circulation coolant flow, and a pump on the loop can drive forced circulation. Coolant direction may be reversed through the heat exchanger in different modes. Loops may be installed directly on existing isolation condenser systems or come off of a primary loop generating electricity commercially. Actuation valves may isolate and actuate the system merely by disallowing or allowing coolant flow. Different flow modes and coolant direction may be similarly achieved by pump actuation and/or valve opening/closing. Beyond the pump and simple valve actuation, loops may be entirely passive.

Abstract: A sodium-cooled nuclear reactor includes at least one electromagnetic pump assembly and a backflow reduction pipe. The backflow reduction pipe may include an inlet, an outlet, at least one tubular section having a first length and a first diameter, and at least one fluid diode section between the inlet and the outlet.

Abstract: A method and apparatus of limiting power of a boiling water nuclear reactor system includes a reactor pressure vessel, a reactor core disposed in the reactor pressure vessel, a core shroud surrounding the reactor core, a downcomer region disposed between an inner surface of the reactor pressure vessel and the core shroud, a steam line connected to an upper end of the reactor pressure vessel and a condenser system that receives steam from the reactor pressure vessel. A portion of the condenser system condensate is returned to the reactor pressure vessel of the boiling water reactor inside the core barrel above the core rather than into the downcomer. Returning the condensate in this way increases the effectiveness of an isolation condenser system or if the condensate is a portion of the feedwater from the main condenser it provides an effective means to regulate core flow and core power.

Abstract: A nuclear power plant includes a nuclear structure, a frontline support equipment, and a support structure. The nuclear structure includes, and is configured to protect from incurring damage due to a damaging event, at least one of a nuclear reactor or a nuclear fuel storage. The frontline support equipment is configured to perform a fundamental safety function. The support structure is spatially separate from the nuclear structure and includes an initiating support equipment configured to trigger the frontline support equipment to perform the fundamental safety function such that the fundamental safety function is performed independently of the initiating support equipment subsequent to the triggering. The support structure may be a non-protected structure that is not configured to protect the initiating support equipment from incurring damage due to the damaging event.

Abstract: EDM assemblies mount on a machining surface and discharge rotating sub-electrodes against the surface. The sub-electrodes can also revolve about another shared axis while discharging. Rotation and revolution may be achieved with planetary gears fixed with the sub-electrodes and meshing with a stationary sun gear. Several sub-electrodes can be used in a single assembly. Downward movement of the sub-electrodes from a central shaft on the mount allows several inches of the surface to be machined. Assemblies are usable in a nuclear reactor during a maintenance period to machine a hole for a replacement manway cover underwater in the flooded reactor. The differing rotational movements and vertical movement can be independently controlled with separate motors in the assembly. Power and controls may be provided remotely through an underwater connection.

Abstract: An electromagnetic pump (EMP) for a liquid metal-cooled nuclear reactor includes a pump casing, concentric inner and outer flow ducts collectively defining a flow annulus extending coaxially with a longitudinal axis of the EMP, and induction coils configured to control the flow of liquid metal coolant through the flow annulus based on electrical power received from the power supply. At least one of the inner flow duct or the outer flow duct includes a gamma shielding material configured to block gamma rays from entering an interior of the EMP from the flow annulus. The pump casing may include a neutron absorber material configured to absorb neutrons entering the pump casing from an exterior of the EMP. The EMP may include a neutron moderator material on an outer surface of the pump casing and configured to moderate neutrons entering the pump casing to be absorbed by the neutron absorber material.

Abstract: A nozzle expansion tool includes a frame with a drive system on the frame. A rotary mandrel is drivingly connected to the drive system and is engageable with an expansion roller device. A plurality of vacuum cups are mounted to the frame and each include a vacuum fitting adapted to be connected to a vacuum source. A depth adjustment mechanism is connected to the expansion roller device and is configured to adjust a distance that the expansion roller device extends from the frame.

Abstract: A nuclear power plant includes a nuclear structure, a frontline support equipment, and a support structure. The nuclear structure includes, and is configured to protect from incurring damage due to a damaging event, at least one of a nuclear reactor or a nuclear fuel storage. The frontline support equipment is configured to perform a fundamental safety function. The support structure is spatially separate from the nuclear structure and includes an initiating support equipment configured to trigger the frontline support equipment to perform the fundamental safety function such that the fundamental safety function is performed independently of the initiating support equipment subsequent to the triggering. The support structure may be a non-protected structure that is not configured to protect the initiating support equipment from incurring damage due to the damaging event.