Self-powered neutron-gamma integrated detector

Abstract

The embodiment of the invention relates to the field of neutron and gamma detection, in particular to a self-powered neutron and gamma integrated detector. The self-powered neutron-gamma integrated detector comprises a probe assembly and a control assembly, the probe assembly comprises a collector, a first insulating layer, a second insulating layer and emitters, the second insulating layer comprises a neutron insulating layer and a gamma insulating layer, and the emitters comprise a neutron emitter and a gamma emitter; the transmission cable is a three-core armored cable; the neutron insulating layer sleeves the outer side of the neutron emitter, and the gamma insulating layer sleeves the outer side of the gamma emitter; the neutron insulating layer is parallel to the gamma insulating layer; the first insulating layer is sleeved with the collecting body, and the bottom of the collecting body is filled with aluminum oxide powder; one end of the connecting device is connected with the receiving body, and the other end is connected with the cable housing. According to the embodiment, on-line measurement of the neutron signal and the gamma signal can be simultaneously carried out under the condition of high-temperature and high-pressure strong irradiation, and on-line monitoring of the neutron flux and the gamma flux of the reactor core can be simultaneously carried out.

Description

Technical Field

[0001] The embodiments of the present application relate to the field of neutron-gamma detection, and in particular to a self-powered neutron-gamma integrated detector. Background Art

[0002] Core neutron flux detection plays a vital role in the operation of nuclear reactors. It is the core technical means to ensure the safe and stable operation of nuclear reactors, and is also a key factor in improving the economy and reliability of reactors. By real-time monitoring of neutron flux, the power level, reactivity changes and neutron absorption of the fuel of the reactor can be accurately evaluated, which helps to ensure the safe operation of the reactor and prevent reactor power instability or shutdown caused by low neutron flux. In addition, neutron flux data is crucial for the control and regulation of the reactor. The position of the control rods or other control means can be adjusted according to the real-time neutron flux data to maintain the reactor in the best operating state.

[0003] Core gamma flux detection plays a key role in the safety and performance monitoring of nuclear reactors. Real-time monitoring of the core's gamma flux helps determine the reactor's operating status, power level, and reactivity changes. Changes in gamma flux can reflect the fuel usage in the core, the integrity of the fuel rods, and the effectiveness of the coolant. In addition, gamma flux detection also helps with environmental monitoring and radiation protection, ensuring the safety of the reactor's surrounding environment and personnel.

[0004] However, none of the existing detection technologies can achieve simultaneous online detection of neutrons and gamma rays in harsh environments. Therefore, it is urgent to find a technical solution that can simultaneously perform online measurement of neutrons and gamma rays under high temperature, high pressure and strong irradiation conditions to achieve accurate monitoring of the reactor operating status. Summary of the invention

[0005] The content of this application is used to introduce concepts in a brief form, which will be described in detail in the detailed implementation section below. The content of this application is not intended to identify the key features or essential features of the technical solution claimed for protection, nor is it intended to limit the scope of the technical solution claimed for protection.

[0006] Some embodiments of the present application propose a self-powered neutron-gamma integrated detector to solve one or more of the technical problems mentioned in the above background technology section.

[0007] In the first aspect, some embodiments of the present application provide a self-powered neutron-gamma integrated detector, which includes: a probe assembly, a transmission cable, and a connecting device, characterized in that the above-mentioned probe assembly includes: a collector, a first insulating layer, a second insulating layer, and an emitter, wherein the above-mentioned second insulating layer includes: a neutron insulating layer and a gamma insulating layer, and the above-mentioned emitter includes: a neutron emitter and a gamma emitter; the transmission cable is a three-core armored cable, including: a cable shell, a cable core wire, wherein the cable core wire includes: a neutron signal core wire, a gamma signal core wire, a compensation core wire; the neutron emitter is connected to the neutron signal core wire, and the gamma emitter is connected to the gamma signal core wire; the neutron insulating layer is sleeved on the outside of the neutron emitter, and the gamma insulating layer is sleeved on the outside of the gamma emitter; the neutron insulating layer and the gamma insulating layer are parallel and nested in the first insulating layer at the same time; the collector is sleeved on the outside of the first insulating layer, and the bottom of the collector is filled with alumina powder to separate the collector from the emitter; one end of the connector is connected to the collector, and the other end of the connector is connected to the cable casing.

[0008] Optionally, the neutron emitter is made of rhodium material; and the gamma emitter is made of tungsten material.

[0009] Optionally, the neutron insulation layer is made of alumina ceramic material; the gamma insulation layer is made of alumina ceramic material; and the first insulation layer is made of alumina ceramic material.

[0010] Optionally, the collector is made of solid solution strengthened alloy material; the cable core is made of solid solution strengthened alloy material; the insulation material of the transmission cable is made of alumina powder; and the cable casing is made of solid solution strengthened alloy material.

[0011] Optionally, the neutron emitter is cylindrical; the gamma emitter is cylindrical; the neutron insulating layer is cylindrical; the gamma insulating layer is cylindrical; the first insulating layer is cylindrical; and the collector is cylindrical with a closed bottom.

[0012] Optionally, the rear end of the transmission cable may be connected to an electronics system for reading out neutron and gamma data.

[0013] Optionally, in the neutron-gamma mixed field, the neutron emitter and neutrons undergo a radiation capture reaction to generate radioactive nuclides which then decay to produce β electrons. The β electrons pass through the neutron insulating layer and continue to pass through the first insulating layer before being collected by the collector. The generated current signal is transmitted to the electronics system via a transmission cable.

[0014] Optionally, in the neutron-gamma mixed field, the gamma emitter and gamma photons undergo Compton scattering and photoelectric effect to generate electrons, which pass through the gamma insulating layer and then continue to pass through the first insulating layer before being collected by the collector. The generated current signal is transmitted to the electronics system via a transmission cable.

[0015] The above-mentioned various embodiments of the present application have the following beneficial effects: The self-powered neutron-gamma integrated detector provided by the present application includes: a probe, a transmission cable, and a connector connecting the probe and the transmission cable. The probe part is used to detect neutron and gamma signals, and the transmission cable transmits the current signal to the back-end electronics system, and the neutron flux data and gamma flux data can be obtained through the current signal. The present application has a neutron emitter and a gamma emitter, and a dual-emitter structure can output neutron signals and gamma signals at the same time, realizing self-powered neutron-gamma integrated detection technology. Secondly, the transmission cable includes three core wires, two of which are signal core wires for transmitting neutron signals and gamma signals, and one is a compensation core wire. The compensation core wire can compensate for the background signal generated by the transmission cable, which is realized by designing a differential circuit through the back-end electronics system.

[0016] The technical solution of the application can realize the online measurement of neutron signals and gamma signals at the same time under the harsh conditions of high temperature, high pressure and strong radiation. For example, the neutron flux and gamma flux of the reactor core can be monitored online at the same time. The detector processed by the technical solution of the application has the advantages of miniaturization, integration, full solid state, high temperature and high pressure resistance, radiation resistance, no need for external power supply, etc. It is easy to process and manufacture during the production process, simple to operate during use, and has a long service life. BRIEF DESCRIPTION OF THE DRAWINGS

[0017] The above and other features, advantages and aspects of the embodiments of the present application will become more apparent with reference to the following detailed description in conjunction with the accompanying drawings. Throughout the accompanying drawings, the same or similar reference numerals represent the same or similar elements. It should be understood that the drawings are schematic and that components and elements are not necessarily drawn to scale.

[0018] Figure 1 It is a structural schematic diagram of the self-powered neutron-gamma integrated detector of the present application; Figure 2 This is a structural diagram of a probe assembly of the self-powered neutron-gamma integrated detector of the present application; Figure 3 It is a structural diagram of a transmission cable of the self-powered neutron-gamma integrated detector of the present application; Figure 4 is a cross-sectional view of a probe assembly of the self-powered neutron-gamma integrated detector of the present application; Description of reference numerals: 1-probe assembly; 2-transmission cable; 3-connector; 11-collector; 12-first insulating layer; 121-side wall of first insulating layer; 122-bottom powder of first insulating layer; 131-neutron insulating layer; 132-gamma insulating layer; 141-neutron emitter; 142-gamma emitter; 21-transmission cable casing; 221-neutron signal core wire, 222-gamma signal core wire, 223-compensation core wire; 23-insulating material of transmission cable; 24-transmission cable connector; 25-transmission cable braided wire; 26-transmission cable aviation plug. DETAILED DESCRIPTION

[0019] Embodiments of the present application will be described in more detail below with reference to the accompanying drawings. Although certain embodiments of the present application are shown in the accompanying drawings, it should be understood that the present application can be implemented in various forms and should not be construed as being limited to the embodiments set forth herein. On the contrary, these embodiments are provided to provide a more thorough and complete understanding of the present application. It should be understood that the drawings and embodiments of the present application are only for exemplary purposes and are not intended to limit the scope of protection of the present application.

[0020] It should also be noted that, for ease of description, only the parts related to the invention are shown in the drawings. In the absence of conflict, the embodiments and features in the embodiments of the present application can be combined with each other.

[0021] It should be noted that the concepts such as "first" and "second" mentioned in this application are only used to distinguish different devices, modules or units, and are not used to limit the order or interdependence of the functions performed by these devices, modules or units.

[0022] It should be noted that the modifications of "one" and "plurality" mentioned in the present application are illustrative rather than restrictive, and those skilled in the art should understand that unless otherwise clearly indicated in the context, it should be understood as "one or more".

[0023] The names of the messages or information exchanged between multiple devices in the embodiments of the present application are only used for illustrative purposes and are not used to limit the scope of these messages or information.

[0024] The present application will be described in detail below with reference to the accompanying drawings and in combination with embodiments.

[0025] Figure 1 It is a structural schematic diagram of the self-powered neutron-gamma integrated detector of the present application; Figure 2 This is a structural diagram of a probe assembly of the self-powered neutron-gamma integrated detector of the present application; Figure 3 It is a structural diagram of a transmission cable of the self-powered neutron-gamma integrated detector of the present application; Figure 4 It is a cross-sectional view of the probe assembly of the self-powered neutron-gamma integrated detector of the present application.

[0026] In some embodiments, the self-powered neutron-gamma integrated detector comprises: a probe assembly, a transmission cable, and a connecting device. Figure 1 The example includes: a probe assembly 1, a transmission cable 2, and a connecting device 3. The connecting device 3 is used to connect the probe assembly and the transmission cable.

[0027] In some embodiments, the probe assembly includes: a collector, a first insulating layer, a second insulating layer, and an emitter. The second insulating layer includes: a neutron insulating layer and a gamma insulating layer, and the emitter includes: a neutron emitter and a gamma emitter. The neutron emitter is made of rhodium material; the gamma emitter is made of tungsten material. The neutron insulating layer is made of alumina ceramic material; the gamma insulating layer is made of alumina ceramic material; the first insulating layer is made of alumina ceramic material. The collector is made of solid solution strengthened alloy material; the cable core wire is made of solid solution strengthened alloy material; the insulation material of the transmission cable is made of alumina powder; the cable shell is made of solid solution strengthened alloy material. The neutron emitter is cylindrical; the gamma emitter is cylindrical; the neutron insulating layer is cylindrical; the gamma insulating layer is cylindrical; the first insulating layer is cylindrical; the collector is a cylindrical with a closed bottom.

[0028] exist Figure 2 In the figure shown, the probe assembly includes: a collector 11, a first insulating layer 12, a second insulating layer 13, and an emitter 14; the first insulating layer 12 includes: a first insulating layer side wall 121 and a first insulating layer bottom powder 122, the second insulating layer 13 includes: a neutron insulating layer 131 and a gamma insulating layer 132, and the emitter 14 includes: a neutron emitter 141 and a gamma emitter 142. It should be noted that in Figure 2 In the embodiment, one end of the neutron emitter 141 is connected to an ammeter A, and one end of the gamma emitter 142 is connected to an ammeter B. Ammeter A is used to detect the current signal generated by the neutron emitter 141. Ammeter B is used to detect the current signal generated by the gamma emitter 142.

[0029] Therefore, setting the first insulating layer can better maintain the mechanical properties of the detector. The first insulating layer and the second insulating layer are combined to form a total insulating layer. The structure of the two insulating layers can ensure that the insulation performance of the detector will not decrease at high temperatures, and is suitable for core detection under high temperature conditions.

[0030] The role of setting up the second insulating layer (divided into a neutron insulating layer and a gamma insulating layer) is to ensure that an independent structure is formed between the two emitters, so that the neutron signal and the gamma signal do not interfere with each other, which is more conducive to signal output.

[0031] In some embodiments, the transmission cable is a three-core armored cable, including: a cable shell, a cable core wire, wherein the cable core wire includes: a neutron signal core wire, a gamma signal core wire, and a compensation core wire. Thus, a three-core cable structure is set: two signal wires transmit neutron signals and gamma signals respectively at the same time, ensuring real-time measurement, and the compensation core wire is used to offset the influence of background noise.

[0032] In some embodiments, the neutron emitter is connected to the neutron signal core wire, and the gamma emitter is connected to the gamma signal core wire.

[0033] In some embodiments, the neutron insulating layer is sheathed on the outside of the neutron emitter, and the gamma insulating layer is sheathed on the outside of the gamma emitter.

[0034] In some embodiments, the neutron insulation layer and the gamma insulation layer are parallel and nested in the first insulation layer at the same time. After the neutron insulation layer and the gamma insulation layer are nested in the first insulation layer, since all three are cylindrical, an internal cavity structure is formed, and this part can be vacuum assembled to ensure that the signals generated by the neutron emitter and the gamma emitter are collected by the collector.

[0035] The role of setting up a vacuum cavity inside the first insulating layer is to facilitate the transportation of electrons inside the probe, reduce the influence of current signals during the transmission process, reduce noise signals, etc.

[0036] In some embodiments, the collector is sleeved on the outside of the first insulating layer, and the bottom of the collector is filled with aluminum oxide powder to separate the collector from the emitter.

[0037] In some embodiments, one end of the connecting device is connected to the collecting body, and the other end of the connecting device is connected to the cable housing.

[0038] exist Figure 2 , Figure 3 In the figure shown, the collecting body 11 of the probe assembly is made of Inconel600 material (solid solution strengthened alloy material), the side wall 121 of the first insulating layer is made of 99% pure alumina ceramic tube (alumina ceramic material), the bottom powder 122 of the first insulating layer is made of α alumina powder (alumina ceramic material), the neutron insulating layer 131 is made of 99% pure alumina ceramic tube (alumina ceramic material), the gamma insulating layer 132 is made of 99% pure alumina ceramic tube (alumina ceramic material), the neutron emitter 141 is made of 99% pure Rh rhodium material, and the gamma emitter 142 is made of W tungsten material.

[0039] exist Figure 2 , Figure 3In the figure shown, the collector 11 of the probe assembly is processed into a cylindrical shape with a closed bottom; for example, the dimensions of the collector 11 can be: outer diameter 3.0 mm, inner diameter 2.85 mm, length 15 cm, and bottom closed thickness 0.2 mm. The first insulating layer side wall 121 is processed into a cylindrical shape; for example, the dimensions of the first insulating layer side wall 121 can be: outer diameter 2.8 mm, inner diameter 2.5 mm, length 14.9 cm. The neutron insulating layer 131 is processed into a cylindrical shape. For example, the dimensions of the neutron insulating layer 131 can be: outer diameter 1.2 mm, inner diameter 0.9 mm, length 14.9 cm. The gamma insulating layer 132 is processed into a cylindrical shape. For example, the dimensions of the gamma insulating layer 132 can be: outer diameter 1.2 mm, inner diameter 0.9 mm, length 14.9 cm; the neutron emitter 141 is processed into a cylindrical metal wire. For example, the dimensions of the neutron emitter 141 can be: diameter 0.8 mm, length 14.8 cm. The gamma emitter 142 is processed into a cylindrical metal wire. For example, the size of the gamma emitter 142 may be: 0.8 mm in diameter and 14.8 cm in length.

[0040] Therefore, the neutron emitter and the gamma emitter are designed to have the same size, which can ensure that the effective areas of the neutron and gamma incident probes are consistent.

[0041] exist Figure 4 In the figure shown, the transmission cable shell 21 is made of Inconel600 material, the neutron signal core wire 221 is made of Inconel600 material, the gamma signal core wire 222 is made of Inconel600 material, the compensation core wire 223 is made of Inconel600 material, and the insulation material 23 of the transmission cable is made of α-alumina powder (alumina powder).

[0042] Specifically, the processing and manufacturing of the self-powered neutron-gamma integrated detector can be realized according to the following operation process: The first step is to weld one end of the neutron emitter 141 of the probe part and one end of the neutron signal core wire 221 of the transmission cable part; In the second step, one end of the gamma emitter 142 and one end of the gamma signal core wire 222 are welded.

[0043] The third step is to put the neutron insulating layer 131 on the outside of the neutron emitter 141, and put the gamma insulating layer 132 on the outside of the gamma emitter 142, so that the two ends of the neutron emitter 141, the two ends of the gamma emitter 142, the two ends of the neutron insulating layer 131, and the two ends of the gamma insulating layer 132 are on the same horizontal plane.

[0044] The fourth step is to insert the neutron insulation layer 131 and the gamma insulation layer 132 into the first insulation layer side wall 121 in parallel, and keep the first insulation layer 121 and the ends of the neutron insulation layer 131 and the gamma insulation layer at the same level.

[0045] Therefore, the advantages of setting up a parallel structure of two emitters are: it is easy to process, has a uniform shape and size, and is more conducive to assembly.

[0046] The fifth step is to add the first insulating layer bottom powder 122 into the bottom closed end of the collecting body 11 and compact it.

[0047] The sixth step is to nest the collector 11 outside the first insulating layer side wall 121 to complete the assembly of the probe part.

[0048] In the seventh step, laser welding is used to connect the probe assembly 1 and the transmission cable 2 through the connector 3, the thick end of the connector 3 and the outside of the probe part collector 11 are welded, and the thin end of the connector 3 and the transmission cable part outer shell 21 are welded to form a closed structure of the detector.

[0049] In the eighth step, the transmission cable connector 24, the transmission cable braided wire 25, the transmission cable aviation plug 26 and other components are welded at the rear end. The rear end can be connected to the electronics system to read and calculate the output signal of the probe.

[0050] In some embodiments, the rear end of the transmission cable may be connected to an electronic system for reading out neutron and gamma data. The electronic system may be a fast electronic system.

[0051] In the neutron-gamma mixed field, the neutron emitter and neutrons undergo radiation capture reaction to generate radioactive nuclides which decay to produce beta electrons. The beta electrons pass through the neutron insulating layer and continue to pass through the first insulating layer before being collected by the collector. The generated current signal is transmitted to the electronics system through a transmission cable.

[0052] Specifically, when neutrons are incident on the probe assembly of the self-powered neutron gamma integrated detector, the neutrons pass through the collector 11, the first insulating layer 12, the neutron insulating layer 131, and the neutron emitter 141 to undergo a radiation capture reaction, generating radioactive nuclides and decaying, emitting β electrons, which pass through the neutron insulating layer 131 and the first insulating layer 12 to reach the collector 11 and are collected by the collector 11. This process can form a current signal a, which is transmitted to the back-end electronics system for reading through the neutron signal core wire 221 in the transmission cable 2. The current signal a is proportional to the number of β electrons, which is proportional to the number of neutrons, so that the measurement of neutron flux can be achieved.

[0053] In the neutron-gamma mixed field, the gamma emitter and gamma photons undergo Compton scattering and photoelectric effect to generate electrons, which pass through the gamma insulating layer and then the first insulating layer before being collected by the collector. The generated current signal is transmitted to the electronics system through a transmission cable.

[0054] Specifically, when a gamma photon enters the probe of the self-powered neutron gamma integrated detector, the gamma photon passes through the collector 11, the first insulating layer 12, the gamma insulating layer 132, and the gamma emitter 142 to produce Compton effect, photoelectric effect, and electron pair effect, and emits electrons. The electrons pass through the gamma insulating layer 132 and the first insulating layer 12 to reach the collector 11, and are collected by the collector 11. This process can form a current signal b, which is transmitted to the back-end electronics system for reading through the gamma signal core wire 222 in the transmission cable 2. The current signal b is proportional to the number of electrons, and the number of electrons is proportional to the number of photons, so that the measurement of gamma flux can be achieved.

[0055] The above-mentioned various embodiments of the present application have the following beneficial effects: The self-powered neutron-gamma integrated detector provided in the present embodiment includes: a probe assembly, a transmission cable, and a connector connecting the probe and the transmission cable. The technical solution of the present invention can be used to simultaneously perform online measurement of neutron signals and gamma signals under harsh conditions of high temperature, high pressure and strong irradiation. For example, the neutron flux and gamma flux of the reactor core can be monitored online at the same time. The detector processed by the technical solution of the present invention has the advantages of miniaturization, integration, full solid-state, resistance to high temperature and high pressure, resistance to radiation, and no need for an external power supply. It is easy to process and manufacture during the production process, simple to operate during use, and has a long service life. The technical features of the above embodiments can be combined arbitrarily. To make the description concise, not all possible combinations of the technical features in the above embodiments are described. However, as long as there is no contradiction in the combination of these technical features, they should be considered to be within the scope of this specification.

[0056] The above embodiments are only used to illustrate the technical solutions of the present application, rather than to limit them. Although the present application has been described in detail with reference to the aforementioned embodiments, a person skilled in the art should understand that the technical solutions described in the aforementioned embodiments may still be modified, or some of the technical features may be replaced by equivalents. However, these modifications or replacements do not deviate the essence of the corresponding technical solutions from the protection scope of the technical solutions of the embodiments of the present application.

Claims

1. A self-powered neutron-gamma integrated detector, the self-powered neutron-gamma integrated detector comprising: The probe assembly, transmission cable, and connecting device are characterized in that: The probe assembly comprises: a collector, a first insulating layer, a second insulating layer, and an emitter, wherein the second insulating layer comprises: a neutron insulating layer and a gamma insulating layer, and the emitter comprises: a neutron emitter and a gamma emitter; The transmission cable is a three-core armored cable, including: a cable shell, a cable core wire, wherein the cable core wire includes: a neutron signal core wire, a gamma signal core wire, and a compensation core wire; The neutron emitter is connected to the neutron signal core wire, and the gamma emitter is connected to the gamma signal core wire; The neutron insulating layer is sheathed on the outside of the neutron emitter, and the gamma insulating layer is sheathed on the outside of the gamma emitter; The neutron insulation layer and the gamma insulation layer are parallel and are simultaneously nested in the first insulation layer; The collector is sleeved on the outside of the first insulating layer, and the bottom of the collector is filled with aluminum oxide powder to separate the collector from the emitter; One end of the connecting device is connected to the collecting body, and the other end of the connecting device is connected to the cable housing.

2. The self-powered neutron-gamma integrated detector according to claim 1, characterized in that: The neutron emitter is made of rhodium material; the gamma emitter is made of tungsten material.

3. The self-powered neutron-gamma integrated detector according to claim 1, characterized in that: The neutron insulation layer is made of alumina ceramic material; the gamma insulation layer is made of alumina ceramic material; and the first insulation layer is made of alumina ceramic material.

4. The self-powered neutron-gamma integrated detector according to claim 1, characterized in that: The collector is made of solid solution strengthened alloy material; the cable core wire is made of solid solution strengthened alloy material; the insulation material of the transmission cable is made of alumina powder; and the cable shell is made of solid solution strengthened alloy material.

5. The self-powered neutron-gamma integrated detector according to claim 1, characterized in that: The neutron emitter is cylindrical; the gamma emitter is cylindrical; the neutron insulating layer is cylindrical; the gamma insulating layer is cylindrical; the first insulating layer is cylindrical; and the collector is cylindrical with a closed bottom.

6. The self-powered neutron-gamma integrated detector according to claim 5, characterized in that: The rear end of the transmission cable can be connected to an electronics system for reading out neutron and gamma data.

7. The self-powered neutron-gamma integrated detector according to claim 6, characterized in that: In the neutron-gamma mixed field, the neutron emitter and neutrons undergo radiation capture reaction to generate radioactive nuclides which decay to produce beta electrons. The beta electrons pass through the neutron insulating layer and continue to pass through the first insulating layer before being collected by the collector. The generated current signal is transmitted to the electronics system through a transmission cable.

8. The self-powered neutron-gamma integrated detector according to claim 6, characterized in that: In the neutron-gamma mixed field, the gamma emitter and gamma photons undergo Compton scattering and photoelectric effect to generate electrons, which pass through the gamma insulating layer and the first insulating layer before being collected by the collector. The generated current signal is transmitted to the electronics system through a transmission cable.

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