Neutron target system

Abstract

The present application relates to a neutron target system. The neutron target system comprises a beam tube cylinder and a target base arranged in the cylinder, the tube wall of the beam tube cylinder has a cooling medium inflow chamber and an outflow chamber; the bottom of the beam tube cylinder has a target cooling structure, the target cooling structure has an incident cavity and a cooling cavity, which are respectively communicated with the cooling medium inflow chamber and the outflow chamber; the incident cavity and the cooling cavity are separated by a jet plate, the cooling cavity is located at the bottom of the target base, the jet plate has jet holes, the jet direction of the jet holes is opposite to the target base; the cooling medium flowing into the incident cavity from the cooling medium inflow chamber is jetted into the cooling cavity through the jet holes and jetted against the lower surface of the target base, and then flows out from the cooling medium outflow chamber, so as to simultaneously realize the cooling of the tube wall of the beam tube cylinder and the target base. The present application solves the problem of low heat dissipation efficiency of the existing neutron target, which leads to the temperature and thermal stress of the target base exceeding the limit.

Description

Technical Field

[0001] This invention relates to the field of nuclear technology, and more specifically to neutron target systems. Background Technology

[0002] A neutron generator uses an ion beam to bombard a target sheet, causing a nuclear reaction to produce the desired neutrons for use in fields such as detection, imaging, and medicine. The neutron target is the core component of the neutron generator. The nuclear reaction on the target sheet generates a large amount of heat, and theoretically, the higher the beam power, the higher the neutron yield and the higher the surface temperature of the target sheet. However, due to limitations in the substrate's heat dissipation capacity, high power can lead to target sheet temperature or thermal stress exceeding limits and causing damage. Therefore, to ensure the safe operation of the neutron target at high power, continuous and efficient heat dissipation of the target sheet is necessary.

[0003] Currently, the conventional heat dissipation method is to add cooling channels inside the neutron target. By increasing the heat exchange area of ​​the cooling channels and increasing the local flow velocity, the heat exchange capacity of the target can be improved. However, this method has limited ability to improve the heat transfer coefficient. In particular, when bombarding the target with a large area and high heat flux, there will still be problems of temperature exceeding the limit and thermal stress exceeding the limit. Summary of the Invention

[0004] The purpose of this invention is to provide a neutron target system to solve the problem that existing neutron target systems have low heat dissipation efficiency, which leads to excessive target substrate temperature and thermal stress.

[0005] To achieve the above objectives, the technical solution adopted by the present invention is as follows: A neutron target system includes a beam tube and a target substrate disposed inside the tube, wherein the wall of the beam tube has a cooling medium inflow chamber and a cooling medium outflow chamber. The bottom of the beam tube is provided with a target cooling structure, which has an injection chamber and a cooling chamber. The injection chamber is connected to the cooling medium inflow chamber through an inflow channel on the target cooling structure, and the cooling chamber is connected to the cooling medium outflow chamber through an outflow channel on the target cooling structure. The injection chamber and the cooling chamber are separated by a jet plate. The cooling chamber is located at the bottom of the target substrate. The jet plate is provided with jet holes, and the jet direction of the jet holes is directed towards the lower surface of the target substrate. The cooling medium flowing from the cooling medium inflow chamber into the injection chamber is injected into the cooling chamber through the jet holes and jettisons the lower surface of the target substrate, and then flows out from the cooling medium outflow chamber, so as to simultaneously cool the tube wall of the beam tube and the target substrate.

[0006] Based on the aforementioned technical means, by setting a cooling flow chamber inside the beam tube wall and a target cooling structure at the bottom of the beam tube, and by arranging jet holes on the target cooling structure opposite to the lower surface of the target substrate, efficient heat dissipation of the target substrate is effectively achieved, ensuring the safe operation of the neutron target under high beam current. Simultaneously, the ingenious placement of the cooling flow chamber inside the beam tube wall further cools the beam tube, effectively preventing the problem of temperature exceeding limits caused by reflected particles bombarding the beam tube. This meets the target structure requirements under higher beam currents, thereby achieving a higher neutron yield, demonstrating a significant advantage of achieving two goals at once. This solves the problem of low heat dissipation efficiency in existing neutron targets, which leads to excessive target temperature and thermal stress.

[0007] Preferably, the lower surface of the target substrate has a corrugated structure.

[0008] Preferably, the upper surface of the target substrate has a corrugated structure.

[0009] By setting a corrugated structure on the upper surface of the target substrate, the contact area between the beam and the target substrate is further improved, and the heat flux density on the surface of the target substrate is reduced. By setting a corrugated structure on the lower surface of the target substrate, the contact area between the cooling medium and the target substrate is further improved. Combined with the porous jet method, the heat transfer coefficient of the neutron target is effectively improved, ensuring the safe operation of the neutron target under high-power beam. At the same time, setting both the lower and upper surfaces of the target substrate as corrugated structures effectively compensates for the deformation caused by thermal stress and effectively alleviates the stress expansion during heating.

[0010] Preferably, the radii of the corrugated structure near the center of the target substrate are smaller than the radii of the corrugated structure far from the center.

[0011] In this design, the crests and troughs of the corrugated structure on the target substrate are arranged alternately from the center of the target substrate outwards, and the radii of the crests and troughs increase sequentially from the center of the target substrate outwards.

[0012] For adjacent peaks and troughs of the corrugated structure, the radius of the peak or trough farther from the center of the target substrate is 0.5~5 × the radius of the peak or trough closer to the center of the target substrate × the standard deviation of the normalized distribution of the beam power (Formula I). ​​That is, for adjacent peaks and troughs of the corrugated structure, the radius of the peak farther from the center of the target substrate is 0.5~5 × the radius of the trough closer to the center of the target substrate × the standard deviation of the normalized distribution of the beam power, and for adjacent troughs and peaks of the corrugated structure, the radius of the trough farther from the center of the target substrate is 0.5~5 × the radius of the peak closer to the center of the target substrate × the standard deviation of the normalized distribution of the beam power.

[0013] Beam power normalization distribution is a statistical data processing method that normalizes the distribution of beam power by subtracting the mean from the original value and then dividing by the standard deviation.

[0014] Standard deviation describes the average distance of each data point from the mean; it is also the square root of the average of the squared deviations. Standard deviation directly reflects the dispersion of the dataset. The calculation method is as follows: 1) The power data corresponding to each radial coordinate point is subtracted from the average value of all power data; 2) Add the squares of all the values ​​obtained in 1); 3) Divide the result of 2) by n ("n" refers to the number of radial coordinate points); 4) The square root of the value obtained from 3) is the standard deviation; The standard deviation of the normalized beam power distribution is used to measure the degree of dispersion of the beam power distribution.

[0015] Since the temperature near the center of the target substrate (i.e., the area with the highest particle beam power) is higher than that near the edges, and the heat transfer capacity of the target substrate is closely related to the power distribution of the beam to the target, the peak / trough radius of the corrugated structure on the target substrate near the center is set to be smaller than the trough / peak radius away from the center, while satisfying the size requirement of Formula I. This achieves a match between the heat transfer capacity and the power distribution of the beam to the target, further increasing the heat transfer area at the center of the target substrate and improving the uniformity of stress expansion during heating.

[0016] Preferably, the spacing between adjacent wave peaks near the center of the corrugated structure on the target substrate is smaller than the spacing between adjacent wave peaks farther from the center.

[0017] By setting the spacing between adjacent peaks near the center of the target substrate to be smaller than the spacing between adjacent peaks far from the center, the spacing between adjacent peaks is matched with the power distribution of the beam, effectively solving the problem of uneven heat flux density distribution on the target substrate caused by different beam power distributions; at the same time, it also increases the heat exchange area between the bottom of the target substrate and the cooling medium, improving the heat exchange efficiency.

[0018] Preferably, the jet hole located at the center of the jet plate is arranged to correspond to the central valley of the corrugated structure on the target substrate.

[0019] Preferably, the non-central jet holes on the jet plate are arranged to correspond to the crests of the corrugated structure on the target substrate.

[0020] By arranging the central jet holes on the jet plate to correspond to the central troughs of the corrugated structure on the target substrate, and arranging the non-central jet holes on the jet plate to correspond to the crests of the corrugated structure on the target substrate, the contact time between the cooling medium and the target substrate is extended, thereby improving the heat exchange efficiency.

[0021] Preferably, the tube wall of the beam tube includes an outer tube wall and an inner tube wall, and the space between the outer tube wall and the inner tube wall is divided into a cooling medium inflow chamber and a cooling medium outflow chamber by a partition.

[0022] Preferably, the inflow channels are distributed at intervals at the bottom of the cooling medium inflow chamber, and the outflow channels are distributed at intervals at the bottom of the cooling medium outflow chamber.

[0023] Preferably, the jet holes are arranged in a radial pattern outward from the center of the jet plate, and the diameter of the jet holes near the center of the jet plate is larger than the diameter of the jet holes away from the center of the jet plate.

[0024] Preferably, the diameter of the jet hole located at the center of the jet plate is not less than the diameter of the central trough of the corrugated structure on the target substrate.

[0025] Preferably, the beam tube has an inlet for the cooling medium to flow into the chamber and an outlet for the cooling medium to flow out of the chamber near the top.

[0026] By forming an inlet for the cooling medium to flow into the chamber and an outlet for the cooling medium to flow out of the chamber near the top of the beam tube, the flow time of the cooling medium is effectively extended, ensuring effective heat dissipation of the beam tube wall and avoiding the problem of temperature exceeding the limit caused by reflected particles bombarding the beam tube.

[0027] Preferably, the cooling medium is water, oil, or nanofluid.

[0028] Preferably, the flow rate of the cooling medium is ≥6 kg / s.

[0029] Preferably, the beam power of the particle beam inside the beam tube is ≥30KW.

[0030] Preferably, the target substrate is made of at least one of tantalum, titanium, beryllium, and lithium.

[0031] The beneficial effects of this invention are: The neutron target system of this invention effectively dissipates heat from the target substrate by setting a cooling flow chamber inside the beam tube wall and a target cooling structure at the bottom of the beam tube, and by arranging jet holes on the target cooling structure opposite to the target substrate. This ensures the safe operation of the neutron target under high beam current. At the same time, the clever arrangement of the cooling flow chamber inside the beam tube wall enables direct or indirect cooling of the beam tube wall, preventing beam particles from reflecting back to the tube wall and causing temperature rise, which would affect the lifespan of the beam tube. This meets the target structure requirements under higher beam current, thereby achieving higher neutron yield. It has significant advantages of achieving two goals at once, and also has the advantages of simple structure, convenient assembly, and low production cost. It has promotional application value in the field of nuclear technology. Attached Figure Description

[0032] Figure 1 This is a schematic diagram of the structure of the present invention; Figure 2 This is another structural schematic diagram of the present invention; Figure 3 for Figure 1 Sectional view at point AA along the middle; Figure 4 This is a schematic diagram of the jet plate structure; Among them, 1-beam tube, 11-cooling medium inlet chamber, 12-cooling medium outlet chamber, 13-outer tube wall, 14-inner tube wall, 15-partition plate, 16-inlet, 17-outlet; 2-target substrate, 21-lower surface, 22-upper surface; 3-target cooling structure, 31-inlet cavity, 32-cooling cavity, 33-jet plate, 34-jet hole, 35-inlet channel, 36-outlet channel. Detailed Implementation

[0033] The embodiments of the present invention will be described below with reference to the accompanying drawings and preferred embodiments. Those skilled in the art can easily understand other advantages and effects of the present invention from the content disclosed in this specification. The present invention can also be implemented or applied through other different specific embodiments, and various details in this specification can also be modified or changed based on different viewpoints and applications without departing from the spirit of the present invention. It should be understood that the preferred embodiments are only for illustrating the present invention and not for limiting the scope of protection of the present invention.

[0034] It should be noted that the illustrations provided in the following embodiments are only schematic representations of the basic concept of the present invention. Therefore, the drawings only show the components related to the present invention and are not drawn according to the actual number, shape and size of the components in the actual implementation. In the actual implementation, the form, quantity and proportion of each component can be arbitrarily changed, and the layout of the components may also be more complex.

[0035] Numerous details are explored in the following description to provide a more thorough explanation of embodiments of this application; however, it will be apparent to those skilled in the art that embodiments of this application can be implemented without these specific details.

[0036] Example 1 like Figures 1 to 4 As shown, a neutron target system includes a beam tube 1 and a target substrate 2 disposed inside the tube. The beam tube 1 has a cooling medium inflow chamber 11 and a cooling medium outflow chamber 12 inside its tube wall. The bottom of the beam tube 1 is provided with a target cooling structure 3, which has an injection cavity 31 and a cooling cavity 32. The injection cavity 31 is connected to the cooling medium inflow chamber 11 through the inflow channel 35 on the target cooling structure 3, and the cooling cavity 32 is connected to the cooling medium outflow chamber 12 through the outflow channel 36 on the target cooling structure 3. The injection cavity 31 and the cooling cavity 32 are separated by a jet plate 33. The cooling cavity 32 is located at the bottom of the target substrate 2. The jet plate 33 is provided with jet holes 34, and the jet direction of the jet holes 34 is directed toward the lower surface of the target substrate 2. The cooling medium flowing into the injection cavity 31 from the cooling medium inflow chamber 11 is injected into the cooling cavity 32 through the jet holes 34 and jettisons the lower surface of the target substrate 2, and then flows out from the cooling medium outflow chamber 12, so as to simultaneously cool the tube wall of the beam tube 1 and the target substrate 2.

[0037] By setting a cooling flow chamber inside the beam tube wall and a target cooling structure at the bottom of the beam tube, and by arranging jet holes on the target cooling structure opposite to the lower surface of the target substrate, efficient heat dissipation of the target substrate is effectively achieved, ensuring the safe operation of the neutron target under high beam current. At the same time, the clever arrangement of the cooling flow chamber inside the beam tube wall further cools the beam tube, effectively preventing the problem of temperature exceeding the limit caused by reflected particles bombarding the beam tube, meeting the target structure requirements under higher beam current, and thus obtaining a higher neutron yield, which has a significant advantage of achieving two goals at once.

[0038] The top end of the beam tube 1 is assembled and fixed to the end of the heater beam tube via a flange (Note: The top end of the beam tube serves as a connecting flange, with an inlet for the cooling medium to flow in and an outlet for the cooling medium to flow out). The bottom of the beam tube 1 is sealed to the target cooling structure 3.

[0039] In order to increase the contact area between the cooling medium and the target substrate, reduce the heat flux density on the surface of the target substrate, thereby increasing the heat transfer coefficient of the neutron target and ensuring the safe operation of the neutron target under high beam current, the lower surface 21 and / or the upper surface 22 of the target substrate 2 are made into a corrugated structure. Furthermore, by making the lower surface 21 and the upper surface 22 of the target substrate 2 into a corrugated structure, the deformation caused by thermal stress can also be effectively compensated, and the stress expansion during heating can be alleviated.

[0040] Since the temperature near the center of the target substrate (i.e. the part with the highest particle beam power) is higher than the temperature near the edge, the radii of the corrugated structure near the center of the target substrate 2 are set to be smaller than the radii of the corrugated structure far from the center to ensure the uniformity of temperature distribution on the target substrate 2, thereby improving the uniformity of stress expansion under heat.

[0041] In this embodiment, the radii of the crests and troughs of the corrugated structure are between 2 mm and 60 mm. For adjacent crests and troughs of the corrugated structure, the radius of the crest or trough farther from the center of the target substrate is 0.5 to 5 × the radius of the crest or trough closer to the center of the target substrate × the standard deviation of the normalized distribution of the beam power (Formula I).

[0042] Since the beam power of the target is inconsistent along the radial direction of the target substrate, the spacing between adjacent peaks near the center of the corrugated structure on the target substrate 2 is set to be smaller than the spacing between adjacent peaks far from the center. This makes the spacing between adjacent peaks match the beam power of the target, thus solving the problem of uneven heat flux density distribution caused by different beam power. This design also increases the heat exchange area between the bottom of the target substrate and the cooling medium, improving the heat exchange efficiency.

[0043] In order to improve heat exchange efficiency and extend the contact time between the cooling medium and the target substrate, the jet hole 34 located in the center of the jet plate 33 is arranged to correspond to the center trough of the corrugated structure on the target substrate 2. At the same time, the non-central jet holes 34 on the jet plate 33 are arranged to correspond to the wave crests of the corrugated structure on the target substrate 2.

[0044] The tube wall of the beam tube 1 includes an outer tube wall 13 and an inner tube wall 14. The space between the outer tube wall 13 and the inner tube wall 14 is divided into a cooling medium inflow chamber 11 and a cooling medium outflow chamber 12 by a partition 15.

[0045] The incident cavity 31 is connected to the inflow channel 35 on the target cooling structure 3, and the cooling cavity 32 is connected to the outflow channel 36 on the target cooling structure 3. Multiple inflow channels 35 are distributed at intervals on the bottom of the cooling medium inflow chamber 11, and multiple outflow channels 36 are distributed at intervals on the bottom of the cooling medium outflow chamber 12.

[0046] In this embodiment, the jet plate 33 is generally in the shape of a disc, and the jet holes 34 on the jet plate 33 are arranged in a radiating pattern from the center of the jet plate 33. Since the temperature of the target substrate 2 near the center is higher than that near the edge, in order to ensure the uniformity of temperature distribution on the target substrate 2, the diameter of the jet hole 34 near the center of the jet plate 33 is set to be larger than the diameter of the jet hole 34 far from the center of the jet plate 33, and the diameter of the jet hole 34 located at the center of the jet plate 33 is not less than the diameter of the central trough of the corrugated structure on the target substrate 2, so that the flow rate of the cooling medium near the center of the target substrate 2 is greater than the flow rate of the cooling medium near the edge of the target substrate 2.

[0047] In order to maximize the flow time of the cooling medium within the beam tube to ensure effective heat dissipation from the beam tube wall and thus effectively prevent the beam tube from being bombarded by reflected particles and causing temperature exceedances, an inlet 16 for the cooling medium to flow into the chamber 11 and an outlet 17 for the cooling medium to flow out of the chamber 12 are formed near the top of the beam tube 1.

[0048] The cooling medium can be selected from fluids such as water, oil, or nanofluids, with a flow rate ≥ 6 kg / s. The beam power of the particle beam inside the beam tube is ≥ 30 kW.

[0049] The target substrate 2 can be made of any material suitable for nuclear reactions, such as tantalum, titanium, beryllium or lithium, or a coating process can be applied to the target substrate 2 to achieve the nuclear reaction and produce neutrons.

[0050] Example 2 like Figures 1 to 4 As shown, a neutron target system includes a beam tube 1 with a cylindrical structure and a target substrate 2 disposed inside the tube. The beam tube 1 has a cooling medium inflow chamber 11 and a cooling medium outflow chamber 12 inside its tube wall. The bottom of the beam tube 1 is provided with a target cooling structure 3, which has an injection cavity 31 and a cooling cavity 32. The injection cavity 31 is connected to the cooling medium inflow chamber 11 through the inflow channel 35 on the target cooling structure 3, and the cooling cavity 32 is connected to the cooling medium outflow chamber 12 through the outflow channel 36 on the target cooling structure 3. The injection cavity 31 and the cooling cavity 32 are separated by a jet plate 33. The cooling cavity 32 is located at the bottom of the target substrate 2. The jet plate 33 is provided with jet holes 34, and the jet direction of the jet holes 34 is directed toward the lower surface of the target substrate 2. The cooling medium flowing into the injection cavity 31 from the cooling medium inflow chamber 11 is injected into the cooling cavity 32 through the jet holes 34 and jettisons the lower surface of the target substrate 2, and then flows out from the cooling medium outflow chamber 12, so as to simultaneously cool the tube wall of the beam tube 1 and the target substrate 2.

[0051] The top end of the beam tube 1 is assembled and fixed to the end of the accelerator beam tube via a flange. The bottom of the beam tube 1 is sealed to the target cooling structure 3.

[0052] In order to increase the contact area between the cooling medium and the target substrate, reduce the heat flux density on the surface of the target substrate, thereby increasing the heat transfer coefficient of the neutron target and ensuring the safe operation of the neutron target under high beam current, the lower surface 21 and the upper surface 22 of the target substrate 2 are both made into a corrugated structure. In addition, by making the lower surface 21 and the upper surface 22 of the target substrate 2 into a corrugated structure, the deformation caused by thermal stress can also be effectively compensated and the stress expansion during heating can be alleviated.

[0053] In this embodiment, the vertical distance between the lower surface 21 and the upper surface 22 is 6mm.

[0054] The tube wall of the beam tube 1 includes an outer tube wall 13 and an inner tube wall 14. The space between the outer tube wall 13 and the inner tube wall 14 is divided into a cooling medium inflow chamber 11 and a cooling medium outflow chamber 12 by a partition 15.

[0055] The incident cavity 31 is connected to the inflow channel 35 on the target cooling structure 3, and the cooling cavity 32 is connected to the outflow channel 36 on the target cooling structure 3. Multiple inflow channels 35 are evenly distributed at intervals on the bottom of the cooling medium inflow chamber 11, and multiple outflow channels 36 are evenly distributed at intervals on the bottom of the cooling medium outflow chamber 12.

[0056] Since the temperature near the center of the target substrate is higher than that near the edge, the radii of the corrugated structure near the center of the target substrate 2 are set to be smaller than the radii of the corrugated structure far from the center to ensure the uniformity of temperature distribution on the target substrate 2, thereby improving the uniformity of stress expansion during heating.

[0057] In this embodiment, the target substrate 2 has a circular structure. The corrugated structure has five peaks extending outward from the center of the target substrate 2. The radii of the peaks and troughs extending outward from the center of the target substrate 2 are 2.5 mm (peak), 5 mm (trough), 7.5 mm (peak), 11.25 mm (trough), 15 mm (peak), 20 mm (trough), 25 mm (peak), 32.5 mm (trough), and 40 mm (peak), respectively. The height from the peak to the trough is 8 mm.

[0058] Since the beam power of the target is inconsistent along the radial direction of the target substrate, the spacing between adjacent peaks near the center of the corrugated structure on the target substrate 2 is set to be smaller than the spacing between adjacent peaks far from the center. This makes the spacing between adjacent peaks match the beam power of the target, thus solving the problem of uneven heat flux density distribution caused by different beam power. This design also increases the heat exchange area between the bottom of the target substrate and the cooling medium, improving the heat exchange efficiency.

[0059] In order to improve heat exchange efficiency and extend the contact time between the cooling medium and the target substrate, the jet hole 34 located in the center of the jet plate 33 is arranged to correspond to the center trough of the corrugated structure on the target substrate 2. At the same time, the non-central jet holes 34 on the jet plate 33 are arranged to correspond to the wave crests of the corrugated structure on the target substrate 2.

[0060] In this embodiment, the jet plate 33 has a generally disc-shaped structure, and the jet holes 34 on the jet plate 33 are arranged in a radiating pattern from the center of the jet plate 33. Since the temperature near the center of the target substrate 2 is higher than that near the edge, in order to ensure the uniformity of temperature distribution on the target substrate 2, the diameter of the jet holes 34 near the center of the jet plate 33 is set to be larger than the diameter of the jet holes 34 away from the center of the jet plate 33. Furthermore, the diameter of the jet holes 34 located at the center of the jet plate 33 is not less than the diameter of the central trough of the corrugated structure on the target substrate 2, so that the flow rate of the cooling medium near the center of the target substrate 2 is greater than the flow rate of the cooling medium near the edge of the target substrate 2. This increases the heat transfer area while improving the flow turbulence and enhancing heat transfer. The larger hole diameter in the central region ensures sufficient cooling medium flow for cooling the high heat flux region in the center. Experimental verification shows that the average heat transfer coefficient can reach 110 kW / m². 2 *K can improve heat exchange capacity by approximately 200% compared to traditional design schemes.

[0061] In this embodiment, the radii of the jet holes 34 on the jet plate 33 from the center outward are 4mm, 3mm, 2mm, 1mm, and 0.5mm, respectively.

[0062] In order to maximize the flow time of the cooling medium within the beam tube to ensure effective heat dissipation from the beam tube wall and thus effectively prevent the beam tube from being bombarded by reflected particles and causing temperature exceedances, an inlet 16 for the cooling medium to flow into the chamber 11 and an outlet 17 for the cooling medium to flow out of the chamber 12 are formed near the top of the beam tube 1.

[0063] In this embodiment, a plurality of inlets 16 and outlets 17 are arranged at intervals along the circumference of the beam tube 1 near the top.

[0064] The cooling medium is deionized water, the flow rate of the cooling medium is ≥6kg / s, and the beam power of the particle beam inside the beam tube is ≥30KW.

[0065] The target substrate 2 can be made of any material suitable for nuclear reactions, such as tantalum, titanium, beryllium or lithium, or a coating process can be applied to the target substrate 2 to achieve the nuclear reaction and produce neutrons.

[0066] In summary, the neutron target system of this invention achieves efficient heat dissipation of the target substrate by setting a cooling flow chamber inside the beam tube wall and a target cooling structure at the bottom of the beam tube, and by arranging jet holes on the target cooling structure opposite to the target substrate, ensuring the safe operation of the neutron target under high beam current. Simultaneously, the ingenious arrangement of the cooling flow chamber inside the beam tube wall enables direct or indirect cooling of the beam tube wall, preventing beam particles from reflecting back to the tube wall and causing temperature rise, thus affecting the lifespan of the beam tube. This meets the target structure requirements under higher beam current, thereby achieving higher neutron yield. It has significant advantages in achieving two goals at once, effectively solving the problem of low heat dissipation efficiency in existing neutron targets, which leads to excessive target temperature and thermal stress. Furthermore, it has the advantages of simple structure, convenient assembly, and low production cost, and has significant application value in the field of nuclear reaction technology.

[0067] The above embodiments are merely illustrative of the principles and effects of the present invention and are not intended to limit this application. Any person skilled in the art can modify or alter the above embodiments without departing from the spirit and scope of this application. Therefore, all equivalent modifications or alterations made by those skilled in the art without departing from the spirit and technical concept disclosed in this application should still be covered by the claims of this application.

Claims

1. A neutron target system, comprising a beam tube (1) and a target substrate (2) disposed within the tube, characterized in that, The tube wall of the beam tube (1) has a cooling medium inflow chamber (11) and a cooling medium outflow chamber (12). The bottom of the beam tube (1) is provided with a target cooling structure (3), which has an injection cavity (31) and a cooling cavity (32). The injection cavity (31) is connected to the cooling medium inflow chamber (11) through an inflow channel (35) on the target cooling structure (3), and the cooling cavity (32) is connected to the cooling medium outflow chamber (12) through an outflow channel (36) on the target cooling structure (3). The injection cavity (31) and the cooling cavity (32) are separated by a jet plate (33). (32) Located at the bottom of the target substrate (2), the jet plate (33) is provided with jet holes (34), and the jet direction of the jet holes (34) is directed toward the lower surface of the target substrate (2); the cooling medium flowing into the injection chamber (31) from the cooling medium inflow chamber (11) is injected into the cooling chamber (32) through the jet holes (34) and jet impacts the lower surface of the target substrate (2), and then flows out from the cooling medium outflow chamber (12) to simultaneously cool the tube wall of the beam tube (1) and the target substrate (2); The target substrate (2) has a corrugated structure on its lower surface (21) and upper surface (22); The corrugated structure on the target substrate (2) has a smaller peak and / or trough radius near the center than the peak and / or trough radius away from the center. The spacing between adjacent wave peaks near the center of the corrugated structure on the target substrate (2) is smaller than the spacing between adjacent wave peaks far from the center; The jet hole (34) located at the center on the jet plate (33) is arranged corresponding to the center trough of the corrugated structure on the target substrate (2); The non-central jet holes (34) on the jet plate (33) are arranged corresponding to the crests of the corrugated structure on the target substrate (2); The diameter of the jet hole (34) located at the center on the jet plate (33) is not less than the diameter of the central valley of the corrugated structure on the target substrate (2).

2. The neutron target system according to claim 1, characterized in that, The tube wall of the beam tube (1) includes an outer tube wall (13) and an inner tube wall (14). The space between the outer tube wall (13) and the inner tube wall (14) is divided into a cooling medium inflow chamber (11) and a cooling medium outflow chamber (12) by a partition (15).

3. The neutron target system according to claim 1, characterized in that, The inflow channels (35) are distributed in multiple intervals at the bottom of the cooling medium inflow chamber (11), and the outflow channels (36) are distributed in multiple intervals at the bottom of the cooling medium outflow chamber (12).

4. The neutron target system according to any one of claims 1 to 3, characterized in that, The jet holes (34) are arranged in a radiating pattern from the center of the jet plate (33), and the diameter of the jet holes (34) closer to the center of the jet plate (33) is larger than the diameter of the jet holes (34) farther away from the center of the jet plate (33).

5. The neutron target system according to any one of claims 1 to 3, characterized in that, The beam tube (1) has an inlet (16) for the cooling medium flowing into the chamber (11) and an outlet (17) for the cooling medium flowing out of the chamber (12) near the top.

6. The neutron target system according to any one of claims 1 to 3, characterized in that, The cooling medium is water, oil, or nanofluid; And / or the flow rate of the cooling medium is ≥6 kg / s; And / or the material of the target substrate (2) is selected from at least one of tantalum, titanium, beryllium and lithium.

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