29 results about "Fuel cycle" patented technology

A long-term fuel management method based on accident-tolerant fuel, comprising the following steps: providing replacement fuel assemblies with a first enrichment degree, a second enrichment degree, and a third enrichment degree, wherein 5% < the first enrichment degree < the second enrichment degree < the third enrichment degree, and the replacement fuel assemblies adopt accident-tolerant fuel; taking out 69 groups of fuel assemblies in the reactor and putting them into the spent fuel pool, selecting a group of fuel assemblies with the highest reserve reactivity from the spent fuel pool and setting it at the center of the reactor, and taking 68 groups of replacement fuel assemblies and the remaining fuel assemblies in the reactor as a refueling group; calculating the installation sequence of the refueling group according to the reactor design limit and safety certification conditions and installing it; repeating refueling every 24 months. This method can extend the fuel cycle period to 24 months, effectively improve the fuel utilization rate, and improve the economy of nuclear power plants.

The invention relates to the field of nuclear power operation, in particular to a method and a device for recycling boron removal resin of a primary loop of a nuclear power plant. In the device, the anion exchange filter of the primary loop waste liquid distillation system is connected in parallel with the boron removal filter of the primary loop coolant treatment system. The method comprises the following steps: during normal operation, when the boric acid concentration of a primary loop is reduced to 0.3 g / L-0. 2g / L at the end of a fuel circulation life period, a boron removal filter is put into operation; in the overhaul period, an alkali removal filter and a boron removal filter are put into operation at the same time; and after the overhaul is finished, jointly commissioning a cation exchange filter and a boron removal filter of the primary loop waste liquid distillation system to purify the concentrated boric acid storage tank. The use efficiency of the boron removal filter is improved, the boron removal filter can be used for removing key radionuclide Sb-124 in each overhaul period, and meanwhile the use of new resin and the generation amount of radioactive solid waste are not increased.

The invention provides a neutron detector availability evaluation method, system, equipment and medium, and relates to the technical field of nuclear power plant ex-core nuclear instrumentation system debugging and operation and maintenance, and the evaluation method comprises the steps: obtaining a high-pressure characteristic curve of a neutron detector in a current fuel cycle period; according to the high-pressure characteristic curve, acquiring the plateau inclination of the neutron detector in the current fuel circulation period; according to the high-voltage characteristic curve, the current power level of the reactor, the power level upper limit required to be measured by the neutron detector, the working voltage of the neutron detector and the voltage upper limit of the low-voltage area of the neutron detector, obtaining the voltage margin of the high-voltage characteristic curve of the neutron detector in the current fuel circulation period; and determining the availability of the neutron detector according to the plateau slope and the voltage margin of the high-voltage characteristic curve. According to the evaluation method, system, equipment and medium provided by the invention, the availability of the current neutron detector can be comprehensively evaluated and the residual service life of the neutron detector can be predicted on the premise of not changing out-of-core nuclear instrumentation system equipment.

This invention provides a method, system, device, and medium for assessing the availability of a neutron detector, relating to the field of commissioning and maintenance technology for external nuclear instrumentation systems in nuclear power plants. The assessment method includes: obtaining the high-pressure characteristic curve of the neutron detector for the current fuel cycle; obtaining the plateau slope of the neutron detector for the current fuel cycle based on the high-pressure characteristic curve; obtaining the voltage margin of the high-pressure characteristic curve of the neutron detector for the current fuel cycle based on the high-pressure characteristic curve, the current power level of the reactor, the upper limit of the power level to be measured by the neutron detector, the operating voltage of the neutron detector, and the upper limit of the low-pressure region voltage of the neutron detector; and determining the availability of the neutron detector based on the plateau slope and the voltage margin of the high-pressure characteristic curve. The assessment method, system, device, and medium provided by this invention can comprehensively assess the current availability of the neutron detector and predict its remaining service life without changing the external nuclear instrumentation system equipment.

The invention provides a method for reducing tritium emission of a pressurized water reactor unit, which comprises the following steps of: discharging a primary loop coolant into a refueling water tank in a containment vessel for temporary storage for t time, reducing tritium concentration in the primary loop coolant by utilizing natural decay, and then discharging the primary loop coolant so as to reduce the tritium emission of the pressurized water reactor unit, the t time is a fuel circulation period of the pressurized water reactor unit. The method is reasonable in design and easy to operate, the primary loop coolant is temporarily stored through the refueling water tank in the existing containment, the tritium concentration in the primary loop coolant is reduced through tritium natural decay, tritium emission of the pressurized water reactor unit can be reduced, additional devices and equipment are not needed, and the tritium treatment cost of the pressurized water reactor unit cannot be increased.

The application provides an engine preheating and fuel circulating heating system suitable for extremely cold environment, which comprises an engine, a coolant heater, an oil tank divided into a main oil cavity and a sub oil cavity, a fuel heater and a sub oil cavity oil suction element. The system stores low-grade diesel in the sub oil tank for preheating and stores conventional diesel in the main oil tank to reduce cost. The coolant heater heats the coolant, and the fuel heater heats the diesel in the main oil tank by using the heated coolant. The system also has an oil valve and a driving motor, which can flexibly switch the main oil tank and the sub oil tank to supply oil. In addition, the application also provides a heating method, which comprises the steps of preheating the coolant, starting the engine with low-grade diesel, circulating heating and melting the waxed diesel, and switching to conventional diesel oil supply. Compared with the prior art, the application has significant advantages in cost-effectiveness, engine starting performance, heating efficiency, risk of diesel waxing and system flexibility, and is suitable for stable operation of the engine in extremely cold environment.

The present invention belongs to the field of primary circuit water quality control in nuclear power plants, and specifically relates to a control method for end-of-life boron removal of the primary circuit coolant in nuclear power plants. When the resin in the anion resin exchanger is used at the end of its first fuel cycle, the boric acid concentration is reduced to within the range of 150mg / L to 60mg / L, and the anion exchanger is put into operation alone. When the resin in the anion resin exchanger is used at the end of its second fuel cycle, the boric acid concentration is reduced to within the range of 120mg / L to 60mg / L, and the anion exchanger is put into operation alone. When the boric acid concentration is reduced to less than 60mg / L, the cation exchanger and the anion exchanger are put into operation together. When the total alkali metal or dissolved hydrogen concentration in the primary circuit is at the lower limit of the control value, the cation exchanger is temporarily taken out of operation and resumed after the water quality stabilizes. The present invention can effectively prevent water quality deviations and reduce the amount of radioactive resin solid waste in the primary circuit.

The inflatable cleaning system suitable for the aircraft fuel tank comprises a fuel circulation assembly and an inflation assembly connected to the fuel circulation assembly, the fuel circulation assembly is connected with the aircraft fuel tank, and the inflation assembly comprises a compressed gas source, a filter, a control valve set and a first bidirectional switch which are sequentially connected. The first two-way switch is connected to the fuel oil circulation assembly through a pipeline, inert compressed gas conveyed by the compressed gas source and fuel oil conveyed by the fuel oil circulation assembly enter the fuel oil tank together so that the fuel oil tank can be cleaned, and the cleaned fuel oil flows back into the fuel oil circulation assembly. The cleaning device has the advantages of being compact in structure, convenient to operate, high in cleaning efficiency and the like, and overcomes the defects that an existing cleaning mode is complex in operation and long in consumed time.

The invention belongs to the technical field of helicopter environmental control / thermal management, and discloses a thermal management system and method for a light-weight oil-electricity hybrid power aircraft, the thermal management system comprises liquid cooling circulation, evaporation circulation, high-temperature PAO circulation and fuel circulation, and thermal management of a plurality of heat dissipation components is achieved through one set of liquid cooling circulation and PAO circulation. The problem that heat management of high-power equipment of an aircraft is difficult is solved, and comprehensive management of heat is achieved through the lightweight and integrated design.

The utility model provides a power system cold start heating device and a vehicle, the power system cold start heating device is used for heating fuel oil and cooling liquid of an engine, the power system cold start heating device comprises a heater, a cooling liquid circulation loop, a fuel oil circulation loop, an oil taking pipeline and an electric heating assembly, the cooling liquid circulation loop is arranged between the heater and the engine and used for circulating cooling liquid of the engine between the heater and the engine, the oil taking pipeline is arranged between the heater and the fuel tank and used for providing fuel oil for the heater, and the heater burns the fuel oil to heat the cooling liquid, passing through the heater, of the engine; the fuel oil circulation loop is arranged between the engine and the fuel oil tank and used for providing fuel oil for the engine, and the electric heating assembly is arranged in the fuel oil tank and / or arranged on the fuel oil circulation loop and used for heating the fuel oil.

This invention discloses a simulation method for differential refueling in a pebble bed reactor based on a semi-Lagrange fixed-grid backtracking algorithm, relating to the field of fuel cycle calculation technology for high-temperature gas-cooled reactors. The method includes: calculating the macroscopic burnup depth and poison nucleus density of fuel spheres in each grid of a homogenized pebble bed using a core diffusion program; calculating the backtracking distance of each grid based on the flow velocity in the channel where each grid is located and the time step used in each refueling step, and determining the position before backtracking; calculating weighting coefficients based on this backtracking position, and updating the macroscopic burnup depth and poison nucleus density of fuel spheres in the calculation grid using a cubic spline interpolation function; and finally correcting the calculated macroscopic burnup depth and poison nucleus density using a correction equation. This invention solves the numerical dispersion and oscillation problems existing in traditional methods, significantly improving the smoothness and stability of core physics field calculations under differential refueling conditions.

A self-contained, offshore, underwater nuclear power plant is housed within a hull mounted to the seafloor. An electric line extends from the offshore power plant to an onshore electric load to power the electric load. The body of water provides a heat sink for the power plant, and protection from surface weather, waves, and currents. The hull mounts to the seafloor via a dampener that reduces the transfer of seismic activity from the seafloor to the hull. The hull and power plant may be manufactured at an onshore facility and transported to an offshore location of operation on the seafloor. After completion of a fuel cycle, the hull and power plant may be transported from the offshore location of operation to an onshore maintenance / refueling facility for refueling, repair and later, when obsolete or damaged, for decommissioning.

The utility model belongs to the field of fire-resistant oil circulating flushing of steam turbines, and provides a fire-resistant oil system flushing device which comprises a fire-resistant oil system, an oil filter, a device oil tank and a high-speed flushing valve, and the fire-resistant oil system is provided with an oil return mother pipeline and a fire-resistant oil tank; the oil filter is connected with the fire-resistant oil tank; the temporary device oil tank is connected with the oil filter; and the high-speed flushing valve is respectively connected with the device oil tank and the main oil return mother pipeline. The device is simple and compact in structure, convenient and fast to construct, high in cleaning efficiency and good in effect.

The invention provides a fuel motor car system for a large ship main engine test, which is provided with an oil supply pipeline for connecting an oil outlet of an oil tank with an oil inlet platform and an oil return pipeline for connecting an oil return opening of the oil tank with an oil return end of the platform, and is characterized by comprising a fuel circulating system for supplying and returning fuel, the oil pump is arranged on an oil supply pipeline; the metering system is used for measuring the flow of supplied oil and returned oil and comprises a first flow meter arranged on the oil supply pipeline and a second flow meter arranged on the oil return pipeline; and the filtering system is used for performing multi-stage filtering on the supplied oil and the returned oil, and comprises a multi-stage filter arranged on the oil supply pipeline and a multi-stage filter arranged on the oil return pipeline.

The present application relates to an aero-engine fuel system icing test device and test method. The aero-engine fuel system icing test device includes a supercooled water manufacturing unit to generate liquid water at a set temperature; a supercooled water and fuel collision unit for injecting liquid water at a set temperature into fuel to generate water-containing fuel or ice-containing fuel; a fuel storage unit for storing fuel; a circulation control and heat exchange unit for heating and cooling the fuel in the fuel storage unit; and an ejector pump connected to the circulation control and heat exchange unit and the supercooled water and fuel collision unit through fuel pipelines. The ejector pump is connected to the inlet pipeline of the engine, and is used to suck the water-containing fuel or ice-containing fuel in the fuel pipeline into the inlet pipeline of the engine. The present application provides an aero-engine fuel system icing test device and test method, which can achieve transient icing verification and steady-state icing verification.

The present invention discloses a method for determining output anomaly of a pressurized water reactor nuclear power unit, comprising: obtaining output tracking data of a current fuel cycle period and output tracking data of a historical fuel cycle period of the nuclear power unit; calculating, based on the output tracking data, a steam turbine equivalent steam flow rate, electric power converted to rated thermal power, and electric power converted to 104% of a steam flow rate; making four scatter plots based on the output tracking data of the current fuel cycle period and the historical fuel cycle period, with seawater temperature and condenser steam parameters as the X-axis, and electric power converted to rated thermal power and electric power converted to 104% of a steam flow rate as the Y-axis; and conducting longitudinal comparisons individually or jointly based on the four scatter plots with time as the third dimension, thereby determining whether the unit output is abnormal and determining the section in which the abnormality occurs.

The invention relates to a fuel circulation method of a pebble-bed high-temperature gas cooled reactor, and relates to the field of nuclear energy engineering. The method comprises the following steps: adding fuel elements with low enrichment degree and high mixing ratio into a reactor container, and simultaneously unloading all fuel elements loaded in an initial loading reactor core in the reactor container. Sequentially adding a low-enrichment-degree fuel element and a low-enrichment-degree high-mixing-ratio fuel element into the reactor container, simultaneously unloading a part of fuel elements at the bottom of the reactor core during each addition, and circulating for a first set time; and adding low-enrichment-degree pure fuel elements to the top of the reactor core, and simultaneously unloading the fuel elements which are loaded in the reactor core in a staggered manner. And adding a low-enrichment-degree and high-enrichment-degree mixed fuel element to the top of the reactor core, simultaneously unloading a low-enrichment-degree pure fuel element at the bottom of the reactor core, and circulating for a second set number of times. Through stepped fuel replacement and staggered loading design, the axial power distribution of the reactor core is effectively flattened, the hot-spot temperature is reduced, the fuel utilization rate and the operation economy are improved, and the device is adaptive to a non-stop refueling system.

The invention discloses an automatic measurement and control device for a deuterium-tritium fuel circulation system of a magnetic confinement fusion reactor and a control method, and belongs to the technical field of industrial control, the device comprises an OCS industrial optical bus control system and an SIS safety interlocking system which are dispatched by an intelligent production scheduling system, the OCS industrial optical bus control system and the SIS safety interlocking system are of three-level structures, and the OCS industrial optical bus control system and the SIS safety interlocking system are connected with the intelligent production scheduling system. Comprising a field level, a control level and a monitoring level. The control level of the OCS industrial optical bus control system is connected with the field level through an optical bus, and software definition of signal types is realized by adopting a general I / O module; the SIS safety interlocking system operates independently based on the SIL3 safety integrity level. The OCS industrial optical bus control system is adopted to replace a traditional DCS / PLC architecture, and the problems of electromagnetic interference, poor system collaboration and the like are solved through the optical bus and the universal I / O module; the safety and the redundancy capability are improved through an independent SIS safety interlocking system; meanwhile, intelligent production scheduling control is integrated, and the production efficiency is remarkably improved.

A radiation shield is provided for blocking radiation at a gas turbine piping joint. The radiation shield is configured to surround the gas turbine piping joint. The radiation shield includes at least two shield sections in contact with each other at a pair of flange ends. The at least two shield sections together define an opening. Each of the at least two shield sections includes an inner shell, an outer shell, and insulation disposed between the inner shell and the outer shell. One of the inner shell or the outer shell includes a pipe joint support extending into the opening.

The embodiment of the invention provides an aircraft fuel oil recycling method and system, and belongs to the technical field of aircraft fuel oil recycling. The device comprises an oil collecting port, an oil storage tank, a control box, an oil pump, an oil filter, an oil pipe and a sensor, the sensors comprise an oil level sensor and a differential pressure sensor; the oil level sensor is positioned in the oil storage tank; the differential pressure sensor is connected with the oil filter; the oil collecting port is used for collecting fuel oil of a target oil tank; the target fuel tank comprises an aircraft wing fuel tank and an aircraft central fuel tank; the fuel storage tank is used for storing fuel; the control box is used for electrifying the oil pump; the oil pump is used for pumping fuel oil from the oil storage tank and pressurizing the fuel oil; the oil filter is used for filtering fuel oil; the oil pipe is used for conveying fuel; the oil level sensor is used for monitoring the oil level; the differential pressure sensor is used for monitoring the blocking state of the oil filter. According to the invention, fuel oil can be recycled in aircraft fuel oil precipitation emission training, residual oil is prevented from being generated, and the treatment cost of the fuel oil as industrial waste liquid is saved.

The application discloses a kind of single crystal silicon neutron irradiation monitoring method and system based on vanadium self-powered detector, belong to nuclear engineering field.Therein, single crystal silicon neutron irradiation monitoring method based on vanadium self-powered detector includes the following steps: the corresponding relationship of burnup depth and fuel assembly nuclear composition and the corresponding relationship of axial burnup distribution of fuel assembly and fuel cycle, burnup depth are calculated, and then the corresponding relationship of irradiation channel thermal neutron fluence and burnup cycle, burnup depth is calculated;With the position of irradiation channel thermal neutron fluence not more than given threshold as detector installation area, the corresponding relationship of vanadium self-powered detector signal and irradiation channel thermal neutron fluence installed in detector installation area is calibrated using activated foil, so as to monitor single crystal silicon thermal neutron fluence using vanadium self-powered detector.

A fuel system for a gas turbine engine includes a manifold assembly with an assembly inlet, an assembly outlet, and a plurality of fuel injectors. The manifold assembly also includes at least one fuel manifold fluidically connecting each fuel injector of the plurality of fuel injectors to the assembly inlet and to the assembly outlet. A fuel return line is fluidically connected to the assembly outlet. A fuel circulator pump includes a pump outlet fluidically connected to the assembly inlet.

The present application relates to aviation fuel control technical field, specifically, it is a kind of aviation fuel control system and control method thereof;Including fuel circulation system and electrical measurement and control system, electrical measurement and control system is used to control the temperature, flow and pressure of circulating fuel in fuel circulation system;Fuel circulation system includes first regulating valve group, explosion-proof electric heater group, heat preservation assembly, pump group, second regulating valve group and temperature measuring assembly, product export is sequentially connected first regulating valve group, explosion-proof electric heater group, heat preservation assembly and pump group between product import, and product import and product export end are equipped with temperature measuring assembly;The pipeline connected between first regulating valve group, explosion-proof electric heater group and the pipeline connected between pump group, product import are communicated, and the pipeline of this communication is connected second regulating valve group;The present application can control the temperature, pressure and flow of fuel into the product under test, help to improve the stable fuel condition for the combustion test of product, improve the accuracy of combustion test.

The invention relates to an airplane self-adaptive thermal management system comprising evaporation circulation, belongs to the technical field of aviation thermal comprehensive management, and solves the problem that only a liquid cooling circulation system in the prior art is difficult to meet the heat dissipation requirement of an airplane, the airplane self-adaptive thermal management system comprises a control module and a circulation module, the control module comprises a PLC controller and a data acquisition part connected with the PLC controller, a remote control layer, a field control layer and a temperature control part, wherein the temperature control part transmits a control signal generated by the PLC to the circulation module so as to control the circulation mode of the circulation module; the circulation module comprises a compressor, an oil separator, a four-way valve, a condensing heat exchanger, a first selection branch assembly, a two-way liquid storage device and a two-way drying filter which are sequentially connected through a working medium conveying pipeline, wherein the four-way valve is used for working medium circulation reversing operation; the condensing heat exchanger exchanges heat with a fuel oil circulation system; the first selection branch assembly has two conduction modes; the second selection branch assembly has two conduction modes, and the evaporation heat exchanger exchanges heat with the liquid cooling circulation system.

A method for calculating the fission product accumulation in the fuel-cladding gap calculates the in-core accumulation and production rate of target nuclides based on the reactor's fuel cycle management parameters, fuel assembly design parameters, and primary system design parameters. The power distribution and burnup distribution within the fuel rods are then calculated. Based on the fuel rod burnup and temperature distribution, the release and production ratios of different target nuclides from the pellets to the cladding gap are calculated. This method then determines the temporal accumulation of various fission products in the fuel-cladding gap under operating conditions. This method accurately simulates and calculates the fission product accumulation in the fuel-cladding gap, effectively guiding reactor design and safety management. The present invention also provides a calculation device.

The present invention discloses a multi-modal energy supply system for a hypersonic aircraft with a variable topology structure, comprising an oil pump, a turbine gas engine-ramjet combined power unit, a heat pipe, an oil and gas turbine, a generator, a hydrocarbon fuel reforming unit, a SOFC fuel cell, a heat exchanger A, a heat exchanger B, a lithium battery, a supercapacitor, a water storage tank, and an air storage tank; the system includes an onboard fuel cycle, a heat cycle, an energy cycle, and a water cycle. The SOFC fuel cell is connected to the system power module, and the lithium battery and supercapacitor are connected to the system power module. The main energy sources for the system's power generation are the chemical energy of aviation kerosene and an onboard heat source. The energy-efficient utilization architecture of the present invention serves the energy requirements of horizontal take-off and landing hypersonic aircraft, such as the system's wide-speed range cooling requirements and the rapid extraction of high-power pulse energy.

Examples of advanced fuel cycles for fusion reactors are described. Examples include fuel cycles for use in field reverse configuration (FRC) plasma reactors. In some examples, reaction gases may be removed from a fusion reactor between pulses (e.g. plasmoid collisions). In some examples, a D-3He reaction is performed, with the 3He provided from decay of byproducts of previous reactions (e.g. tritium).

The present application relates to a method, device and computer equipment for controlling the quadrant power tilt of a reactor core. The method includes: determining a first expression of the first change rate of the quadrant power tilt corresponding to each quadrant in the fuel cycle with burnable poison according to the first change amount of the quadrant power tilt caused by fuel combustion, the second change amount of the quadrant power tilt caused by burnable poison combustion, and the burnup increment of the reactor core in the fuel cycle with burnable poison; then, according to the first expression of the first change rate of the quadrant power tilt, determining the target parameters of the burnable poison that affect the quadrant power tilt of the reactor core; and controlling the quadrant power tilt of the reactor core according to the target parameters of the burnable poison, so as to control the increase of the quadrant power tilt.

The application discloses a kind of nuclide composition analysis methods of spent fuel assembly, comprising: respectively obtaining the rod position data of AO control rod group and mechanical compensation control rod group in each fuel cycle in each burnup point in core.According to the rod position data of AO control rod group in each fuel cycle in each burnup point, obtain the calculation segmentation number N of AO control rod group.According to the rod position data of mechanical compensation control rod group in each fuel cycle in each burnup point, obtain the maximum burnup depth ratio Z of mechanical compensation control rod group k . According to the calculation segmentation number N of AO control rod group insertion and the maximum burnup depth ratio Z k , the burnup of each axial segmentation of the spent fuel assembly is calculated to obtain the nuclide composition of each axial segmentation of the spent fuel assembly.The present method can analyze the nuclide composition of spent fuel assembly, and the analysis result is accurate.The application also discloses a kind of nuclide composition analysis devices of spent fuel assembly.