Abstract: A temperature change detection apparatus for monitoring temperature change in various portions of a large space includes a trip logic unit configured to execute a trip operation based on receipt of a trip signal at the trip logic unit; a plurality of temperature sensors each including a sensing portion composed of optical fiber cable and each being configured to generate light information indicating an amount of Brillouin scattering that occurs within the sensing portion; a plurality of monitoring units configured such that each monitoring unit determines a temperature value corresponding to each temperature sensor connected to the monitoring unit based on an amount of Brillouin scattering indicated by the light information generated by each of the connected temperature sensors, an each monitoring unit generates a trip signal when a determined temperature value exceeds a running average by more than a threshold amount.

Abstract: A method for suppressing a pyrophoric metal fire may include arranging a suppression system above a containment structure. The suppression system includes a first extinguishing agent. The containment structure is configured to contain and isolate a pyrophoric metal from ambient air. The suppression system is configured to activate upon a leak and ignition of the pyrophoric metal so as to release the first extinguishing agent to suppress the pyrophoric metal fire.

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 liquid metal-cooled nuclear reactor includes, within a reactor pressure vessel, a primary electromagnetic pump (EMP) circulating liquid metal coolant through the reactor core and a backflow EMP. The nuclear reactor may be configured to at least partially mitigate liquid metal coolant backflow in response to a primary EMP failure. The backflow EMP is coupled in series with the primary EMP within the reactor pressure vessel. The backflow EMP may be selectively activated in response to failure of the primary EMP to mitigate liquid metal backflow through the primary EMP. The primary EMP and backflow EMP may receive power from separate power sources. Multiple backflow EMPs may be coupled in parallel to the primary EMP via parallel liquid metal coolant lines. A nuclear reactor may include multiple primary EMPs and multiple sets of backflow EMPs, where each separate set of backflow EMPs is coupled to a separate primary EMP.

Abstract: A passive fire response system is configured to suppress a metallic fire. The system includes a reservoir containing an ionic liquid, at least one outlet in communication with the reservoir, a valve arranged between the reservoir and the outlet, a sensor configured to sense at least one of a hydrogen concentration and a temperature and/or heat, and a controller configured to open the valve and release the ionic liquid if an output from the sensor indicates that the at least one of the hydrogen concentration and the temperature equals or exceeds at least one of a threshold hydrogen concentration and a threshold temperature.

Abstract: A passive safety system for removing decay heat from a nuclear power system may comprise a shroud structure and a heat generator that is within the shroud structure. A thermoelectric device may be disposed in thermal contact with the heat generator. The thermoelectric device is configured to generate a voltage based on a temperature difference between opposite parts of the thermoelectric device. A fan arrangement is disposed above the heat generator and in electrical connection with the thermoelectric device. The fan arrangement is configured to increase a coolant flow through the coolant passage to the outlet opening based on the voltage from the thermoelectric device.

Abstract: A method for suppressing a pyrophoric metal fire may include arranging a suppression system above a containment structure. The suppression system includes a first extinguishing agent. The containment structure is configured to contain and isolate a pyrophoric metal from ambient air. The suppression system is configured to activate upon a leak and ignition of the pyrophoric metal so as to release the first extinguishing agent to suppress the pyrophoric metal fire.

Abstract: A temperature change detection apparatus for monitoring temperature change in various portions of a large space includes a trip logic unit configured to execute a trip operation based on receipt of a trip signal at the trip logic unit; a plurality of temperature sensors each including a sensing portion composed of optical fiber cable and each being configured to generate light information indicating an amount of Brillouin scattering that occurs within the sensing portion; a plurality of monitoring units configured such that each monitoring unit determines a temperature value corresponding to each temperature sensor connected to the monitoring unit based on an amount of Brillouin scattering indicated by the light information generated by each of the connected temperature sensors, an each monitoring unit generates a trip signal when a determined temperature value exceeds a running average by more than a threshold amount.