9 results about "Fission chamber" patented technology

The invention relates to a method and a system for determining working parameters of a nuclear reactor fission chamber detector. The method comprises the following steps: acquiring output current relation information of a detected detector; determining a working voltage test range of the detected detector according to the output current relation information; and sequentially setting the working gas pressure of the detected detector as a plurality of preset gas pressure values, and controlling the detected detector to work based on the working voltage test range after setting the working gas pressure each time. Obtaining and determining counting rate data corresponding to each predetermined air pressure value according to the output current when the neutron beam is injected into the detected detector; and determining ideal working parameters of the detected detector according to the counting rate data. The method can help a worker determine ideal working parameters of the fission chamber detector, and improves the working stability and reliability of the detector.

The invention discloses a nuclear power station cable assembly and a manufacturing process thereof, the nuclear power station cable assembly is used for adapting to a fission chamber detector, the nuclear power station cable assembly comprises a cable body, a first connector and a second connector, and the cable body comprises a core wire, an insulating layer and a shielding shell which are sequentially arranged from inside to outside; the first connector is arranged at one end of the cable body and used for being connected with a fission chamber detector, the first connector comprises a male plug and an explosive welding head, the male plug and the cable body are welded together through the explosive welding head, and the male plug is electrically connected with the core wire; the second connector is arranged at the other end, far away from the first connector, of the cable body, and the second connector and the cable body are welded together; the second connector comprises a coaxial connector, an inner conductor is arranged in the coaxial connector, and the inner conductor is electrically connected with the core wire. The nuclear power station cable assembly provided by the invention has excellent anti-electromagnetic interference performance while being well matched with the fission chamber detector, and can ensure stable transmission of measurement signals of the fission chamber detector.

A neutron detector comprising an optical fission chamber with a reflective optical cavity and a detection head coupled to the chamber comprising an optical lens and an optical fiber coupler. The invention relates to a neutron detector (1) comprising at least one sealed ionization chamber (2) with optical transduction, called an optical fission chamber (OFC) with a single optical cavity, the operation of which is based on optical transduction and which integrates, at one of its longitudinal ends, a window and an optical lens as an optical interface and, at the other end, a mirror to reflect photons traveling in the opposite direction to that of the window. Figure for the abstract: Fig. 9

The invention relates to an analysis method and system for a fission chamber detector of a nuclear reactor. The method comprises the following steps: constructing a simulation model according to the structure of the fission chamber detector to be detected and a Monte Carlo method; wherein when neutrons are injected into the simulation model, fission reaction is simulated, and the number of fission fragments in the fission reaction process is calculated; injecting neutrons into the simulation model through a preset neutron source to determine the number of fission fragments; determining the neutron fluence rate of the simulation model in the process of simulating the fission reaction; and determining the sensitivity of the fission chamber detector to be detected according to the number of the fission fragments and the neutron fluence rate. The simulation model capable of replacing the fission chamber detector to be detected to simulate the fission reaction is constructed based on the Monte Carlo method, and the sensitivity of the fission chamber detector to the thermal neutrons can be accurately detected.

The invention is suitable for the technical field of nuclear detection and embedded systems, and provides an embedded fission chamber assembly and a method for monitoring delayed neutrons thereof.The embedded fission chamber assembly comprises an outer cylinder, the outer cylinder serves as a shell structure of the assembly, a fission chamber body is arranged in the outer cylinder and fixedly installed in the outer cylinder, and the fission chamber body is arranged in the outer cylinder; and the fission chamber main body forms a basic framework of the detection core chamber. The fission chamber main body is internally provided with a gas filling chamber, and the gas filling chamber is used for filling working gas; a collecting electrode and a high-voltage electrode penetrating through the head and the tail are assembled on the collecting electrode in the gas filling chamber, the high-voltage electrode serves as an electric field applying end, and the collecting electrode serves as a signal output end; the outer wall of the collecting electrode and the inner wall of the high-voltage electrode are plated with high-concentration uranium 235 layers; the uranium plating layer serves as a fission material coating and directly participates in nuclear fission reaction caused by neutrons, a large number of fission fragments are generated, and ionization signals are remarkably enhanced. The design of the uranium plating layer can reduce the covering effect of the gamma-ray background on the neutron signal and improve the signal-to-noise ratio of the signal. Double electromagnetic shielding is achieved through the staggered design of the inner shielding layer and the outer shielding layer, external radiation interference and electromagnetic noise are restrained, and the signal distortion rate is reduced.

A method for measuring the dynamic control rod reactivity of a reactor using a fission chamber as an external measuring instrument, the method comprising: maintaining the reactor in a critical state with a set output by inserting a set of reference control rods into the reactor core to a first depth; fully inserting the set of reference control rods into the reactor core from the first depth at a maximum permissible speed, and immediately fully withdrawing the set of reference control rods from the reactor core at a maximum permissible speed; measuring a first signal of the external measuring instrument from before the insertion of the set of reference control rods to after the withdrawal of the set of reference control rods; and determining the static control capability of the set of reference control rods by adding a measurement of the reactor's remaining control capability to a first static reactivity of the reactor calculated using the first signal of the external measuring instrument.

The application discloses a neutron detection structure with flat energy response, which comprises a cylindrical uranium-235 fission chamber detector, a cylindrical moderator body with a cylindrical cavity for accommodating the cylindrical uranium-235 fission chamber detector, wherein the thickness of the moderator body in the radial direction from the inner cylindrical surface of the cylindrical cavity to the outer cylindrical surface of the moderator body is L, and the thickness of the moderator body in the axial direction from the inner end plane of the cylindrical cavity to the outer end plane of the moderator body is also L; wherein the moderator body is made of graphite material, and the thickness L is in the range of 22cm to 25cm; or the moderator body is made of beryllium powder and deionized water with a volume ratio of 4:1, and a curing agent is added for casting forming, so that the beryllium powder is uniformly fixed in the matrix, and the thickness L is in the range of 7cm to 8cm. The application adopts a symmetrical cylindrical geometric configuration, eliminates the directionality of the traditional long counter, and realizes excellent energy response flatness through the selection and matching of the moderator material and the key thickness parameter.

A method of dynamic control rod reactivity measurement for a reactor using a fission chamber as an out-of-reactor measuring instrument includes: maintaining the reactor in a critical state having a set output by inserting a reference control bank into a reactor core to a first depth; completely inserting the reference control bank into the reactor core from the first depth at a maximum allowable speed and immediately completely withdrawing the reference control bank from the reactor core at the maximum allowable speed, and measuring a first signal of the out-of-reactor measuring instrument from before the insertion of the reference control bank to after the withdrawal of the reference control bank; and determining static controllability of the reference control bank by adding residual controllability measurement value of the reactor to a first static reactivity of the reactor calculated using the first signal of the out-of-reactor measuring instrument.

The present application relates to a fission chamber detector signal simulation method and a processing terminal, the method comprising: simulating initial signals output by a fission chamber detector under full working conditions of a unit; obtaining actual working condition signals output by a processing card under full working conditions of the unit; performing reverse calculation on the actual working condition signals to obtain actual characteristic data; and optimizing the initial signals according to the actual characteristic data to obtain simulated signals as close as possible to the actual working condition signals. The present application can simulate detector signals output by an intermediate range fission chamber detector under full working conditions of a unit under a shutdown working condition, so that the calibration work of a signal processing cabinet is not limited by the state of the unit, and the calibration work can be completed under a complete discharge mode.