A stop seal for application of high temperature and high pressure is disclosed. A stop seal contains a first seal member and a second seal member, wherein the stop seal can prevent a fluid of high temperature and high pressure from leaking into an atmospheric space because, when the fluid of high temperature is introduced and the first seal member is moved toward a direction adjacent to a pump shaft, an opposite side of the second seal member is moved from a first position to a second position by the first seal member so as to block a gap between a pump side and a housing.

A method of determining variable trip setpoints at the time of performing a safety analysis on a plant protection system includes: selecting a fixed analysis setpoint including a first analysis setpoint at which safety functions are initiated according to process variables of a power plant, and a first reaching time representing a time required to reach the first analysis setpoint; deriving a variable analysis setpoint satisfying conditions of the first fixed analysis setpoint; and determining a variable trip setpoint by reflecting uncertainty of an instrumentation and control system in relation to the variable analysis setpoint.

Nuclear Aircraft Transportation System “KARAVAN” with its components is represented by a group of inventions in the technical and organizational relations. The main and basic invention is Nuclear Aircraft Transportation System “KARAVAN” (NATS). This invention includes two other ones: Aircraft Thrust Nuclear Power Plant, (ATNPP), which in turn includes—Thermal Power Cycle of ATNPP, (TPC ATNPP). In addition, the represented group of inventions is made up of two more inventions: Maintenance System of ATNPP, (MS ATNPP) and Emergency Response System of NATSK, (ERS NATSK).

The concept of practical implementation of the presented group of inventions involves the fact that ATNPP, which is a large unmanned drone aircraft “Tiagach”, supplies the aero-train composed of a number of passenger liners and cargo transport planes using electric motors with traction electric energy in the air.

The power supply of such an aero-train is based on the onboard Nuclear Power Plant of the aircraft “Tiagach”. In this case, the transmission of electric power to the towed electric aircraft of the aero-train is carried out by means of electric split feeders and cables, connecting and disconnecting of which between airplanes of the aero-train is carried out in the air, by analogy with refueling of airplanes in the air with JP fuel.

During the flight of the aero-train on a logistically optimized route, electric airplanes can detach from and attach to the aero-train, taking off and landing along the flight route of the aero-train using their own electric accumulators. In addition, extra ATNPP may be included in the aero-train during its flight, if it is necessary to increase the thrust. At the same time, due to the use of nuclear power, such ATNPP can remain in the air for a conditionally indefinite period of time.

The invention is aimed at creating cost-effective air freight and passenger traffic.

A dynamic characteristic analysis method of DET and RELAP5 coupling based on a universal instrumental variable method includes steps of: constructing a DET simulation model of a discrete dynamic event tree and modifying TRIP cards of an input file by adding universal instrumental TRIP variables according to state transition types of DET simulation objects, the universal instrumental TRIP variable being variable type or logical type; setting a simulation time of the RELAP5, controlling a simulation step, and analyzing an output result file of each simulation step of the RELAP5; backtracking the RELAP5 according to state transition types of DET simulation objects. The dynamic characteristic analysis method has advantages of simplifying TRIP setting process and method of DET state transition objects in an input file of the RELAP5 required for the coupling of DET and RELAP5, reducing a modeling complexity and improving a modeling efficiency.

A dynamic characteristic analysis method of DET and RELAP5 coupling based on a universal instrumental variable method includes steps of: constructing a DET simulation model of a discrete dynamic event tree and modifying TRIP cards of an input file by adding universal instrumental TRIP variables according to state transition types of DET simulation objects, the universal instrumental TRIP variable being variable type or logical type; setting a simulation time of the RELAP5, controlling a simulation step, and analyzing an output result file of each simulation step of the RELAP5; backtracking the RELAP5 according to state transition types of DET simulation objects. The dynamic characteristic analysis method has advantages of simplifying TRIP setting process and method of DET state transition objects in an input file of the RELAP5 required for the coupling of DET and RELAP5, reducing a modeling complexity and improving a modeling efficiency.

A method for determining at least one threshold value of at least one operating parameter of a nuclear reactor is implemented by an electronic determination system and includes the steps of determining a first threshold value of a respective operating parameter for an operation of the reactor at a first power; and determining a second threshold value of said parameter for an operation of the reactor at a second power. The operation at the lower power of the first and second powers is an operation continued for a duration of at least 8 hours over a 24-hour sliding window. The method also includes determining a third threshold value of said parameter for an operation of the reactor at a third power between the first power and the second power.

A method for determining at least one threshold value of at least one operating parameter of a nuclear reactor is implemented by an electronic determination system and includes the steps of determining a first threshold value of a respective operating parameter for an operation of the reactor at a first power; and determining a second threshold value of said parameter for an operation of the reactor at a second power. The operation at the lower power of the first and second powers is an operation continued for a duration of at least 8 hours over a 24-hour sliding window. The method also includes determining a third threshold value of said parameter for an operation of the reactor at a third power between the first power and the second power.

The method and system for bringing a nuclear power plant to a safe state after extreme effect reduce the temperature of the coolant after extreme effect. The system includes inlet and outlet pipelines, a steam generator, a storage tank and a heat exchanger, a separation tank above the steam generator and connected by two pipelines to a storage tank, a pump, a control unit. The method involves filling the system with coolant, feeding the coolant from the steam generator through the inlet pipeline and the storage tank to the heat exchanger, and feeding the coolant through the outlet pipeline back to the steam generator, wherein the pump is turned on for feeding the coolant and subsequent operation of the system. The first air valve is used to maintain pressure in the system, ensuring the absence of boiling of the coolant.

The method and system for bringing a nuclear power plant to a safe state after extreme effect reduce the temperature of the coolant after extreme effect. The system includes inlet and outlet pipelines, a steam generator, a storage tank and a heat exchanger, a separation tank above the steam generator and connected by two pipelines to a storage tank, a pump, a control unit. The method involves filling the system with coolant, feeding the coolant from the steam generator through the inlet pipeline and the storage tank to the heat exchanger, and feeding the coolant through the outlet pipeline back to the steam generator, wherein the pump is turned on for feeding the coolant and subsequent operation of the system. The first air valve is used to maintain pressure in the system, ensuring the absence of boiling of the coolant.

A method and a system for monitoring a state of a nuclear power plant capable of reducing a state prediction error of a sensor during startup, full power, shut down operation of a nuclear power plant, and of providing an early warning, without an error alarm includes remotely and automatically diagnosing the state of a sensor, device, system and power plant. The method and comprises: a first layer that compares a sensor measurement value and a device measurement value with predicted values so as to detect anomalies of the sensor and the device; a second layer that classifies a type of the sensor and diagnoses the presence or absence of an anomaly of the sensor on the basis of an anomaly value of the sensor provided from the first layer.