Space reactor neutron source assembly and reactor system

Abstract

The utility model belongs to the field of reactor, concretely relates to a kind of space reactor neutron source assembly and reactor system. Wherein space reactor neutron source assembly includes linear moving mechanism and the neutron source rod body of linear moving mechanism output end being arranged, the neutron source rod body includes neutron source functional area, gap and cladding sequentially arranged from inside to outside;The neutron source functional area includes sequentially arranged heat transfer zone, fuel area I, partition area I, neutron source, partition area II and shutdown area. The space reactor neutron source assembly provided by the utility model better utilizes the important position of reactor core center. It can move up and down on the core center, and the structure is simple and compact, efficiently realizes the functions of fuel auxiliary combustion, neutron source start-up, shutdown and reactivity adjustment.

Description

Technical Field

[0001] This utility model belongs to the field of reactors, specifically relating to a space reactor neutron source component and reactor system. Background Technology

[0002] As humanity's exploration of the universe deepens, particularly in deep space and distant solar missions, conventional energy sources such as chemical and solar power are increasingly insufficient to meet the demands of space missions. Therefore, space power sources have become the inevitable and only option. Currently, space reactors are the only choice for high-power space power. Due to increasingly demanding requirements for space power sources, the design requirements for space reactor cores are also rising. At present and in the foreseeable future, space nuclear reactor power technology has been and will continue to develop. Due to its superior performance, the application of space nuclear reactor power technology is also being considered for other space missions.

[0003] Core design is the core area of ​​reactor design. Driven by the needs of deep space and distant solar exploration, and leveraging the advantages of space reactors, major nuclear power nations such as the US, Europe, and Russia are actively conducting research on space reactors. However, in terms of current space reactor core designs, the neutron sources in these designs have limited functionality, primarily serving as neutron source start-up points, failing to fully utilize the crucial location at the reactor core center. Utility Model Content

[0004] The technical problem to be solved by this utility model is to provide a space reactor neutron source assembly and reactor system that makes better use of the important position of the reactor core center, can move up and down at the core center, has a simple and compact structure, and can efficiently realize the functions of fuel-assisted combustion, neutron source start-up, reactor shutdown, and reactivity regulation.

[0005] This utility model provides a space reactor neutron source assembly, including a linear motion mechanism and a neutron source rod disposed at the output end of the linear motion mechanism. The neutron source rod includes a neutron source functional area, a gap and a shell arranged sequentially from the inside to the outside.

[0006] The neutron source functional area includes, in sequence, a heat transfer area, fuel area I, partition area I, neutron source, partition area II, and shutdown area;

[0007] When the neutron source in the neutron source rod is located in the middle of fuel zone II in the core assembly, the linear movement mechanism enables the core assembly to be ignited and started. When the fuel zone I in the neutron source rod corresponds to fuel zone II in the core assembly, the linear movement mechanism enhances the combustion of the core assembly. When the shutdown zone in the neutron source rod corresponds to fuel zone II in the core assembly, the linear movement mechanism enables the core assembly to be shut down or its reactivity to be adjusted.

[0008] Furthermore, the height of fuel zone I is consistent with the height of fuel zone II in the core assembly.

[0009] Furthermore, the height of the heat transfer zone is consistent with the height of the power generation hot end zone in the core assembly.

[0010] Furthermore, the height of the partition region I, the neutron source, and the partition region II is greater than or equal to the height of the core assembly;

[0011] When the neutron source is located in the middle of fuel region II in the core assembly within the neutron source rod, the upper end of the partition region I is flush with the upper end of the core assembly or the upper end of the partition region I protrudes from the upper end of the core assembly; the lower end of the partition region II is flush with the lower end of the core assembly or the lower end of the partition region II protrudes from the lower end of the core assembly.

[0012] Furthermore, the height of the shutdown zone is greater than or equal to the height of the core assembly;

[0013] When the shutdown zone in the neutron source rod corresponds to fuel zone II in the core assembly, the two ends of the shutdown zone are flush with the two ends of the core assembly or the two ends of the shutdown zone protrude from the two ends of the core assembly.

[0014] Furthermore, the heat transfer zone is made of carbon nanotube material; and / or,

[0015] The core material of the fuel pellets in fuel zone I is UN, U 235 Enrichment level 65%; and / or,

[0016] The materials for the partition region I and partition region II are Al2O3; and / or,

[0017] The neutron source material is Am-Be; and / or,

[0018] The material used in the shutdown area is B4C.

[0019] Furthermore, the cladding material is SS316L steel.

[0020] Furthermore, the gap can accommodate the fission-generated gas.

[0021] This invention also provides a reactor system, including a core assembly and the aforementioned space reactor neutron source assembly.

[0022] The beneficial effects of this invention are that the space reactor neutron source assembly provided by this invention makes better use of the crucial location at the reactor core center. It can move vertically up and down at the core center, has a simple and compact structure, and efficiently realizes the functions of fuel-assisted combustion, neutron source start-up, reactor shutdown, and reactivity regulation. Compared to existing neutron source regions that only provide reactor ignition, this invention achieves fuel-assisted combustion, reactor shutdown, and reactivity regulation without increasing circumferential dimensions. This greatly improves the control capability of the reactor system. Attached Figure Description

[0023] Appendix Figure 1 This is a schematic diagram of the longitudinal section of the neutron source rod in this utility model;

[0024] Appendix Figure 2 This is a schematic cross-sectional view of the neutron source rod in this invention;

[0025] Appendix Figure 3 A schematic diagram of the reactor system structure during startup of the neutron source assembly in the space reactor of this utility model;

[0026] Appendix Figure 4 A schematic diagram of the reactor system structure during auxiliary combustion of the neutron source assembly in the space reactor of this utility model;

[0027] Appendix Figure 5 This is a schematic diagram of the reactor system structure when the neutron source component of the space reactor of this utility model is shut down;

[0028] Appendix Figure 6 This is a top view of the neutron source component of the space reactor of this utility model.

[0029] In the diagram, 1-neutron source assembly of the space reactor; 11-heat transfer zone; 12-fuel zone I; 13-separation zone I; 14-neutron source; 15-separation zone II; 16-shutdown zone; 17-gap; 18-cladding; 2-core assembly; 21-fuel zone II; 22-first reflection zone; 23-second reflection zone; 24-third reflection zone; 25-gas chamber; 26-control drum; 27-shielding zone; 28-power generation hot end zone. Detailed Implementation

[0030] The technical solutions of the present utility model will be clearly and completely described below with reference to the accompanying drawings of the embodiments. Obviously, the described embodiments are only some embodiments of the present utility model, and not all embodiments. Based on the embodiments of the present utility model, all other embodiments obtained by those of ordinary skill in the art without creative effort are within the protection scope of the present utility model.

[0031] It should be noted that all directional indicators (such as up, down, left, right, front, back, etc.) in this utility model embodiment are only used to explain the relative positional relationship and movement of each component in a certain specific posture (as shown in the figure). If the specific posture changes, the directional indicator will also change accordingly.

[0032] Furthermore, in this utility model, the use of terms such as "first," "second," etc., is for descriptive purposes only and should not be construed as indicating or implying their relative importance or implicitly specifying the number of technical features indicated. Therefore, a feature defined as "first" or "second" may explicitly or implicitly include at least one of that feature. In the description of this utility model, "multiple" means at least two, such as two, three, etc., unless otherwise explicitly specified.

[0033] In this utility model, unless otherwise explicitly specified and limited, the terms "connection," "fixed," etc., should be interpreted broadly. For example, "fixed" can mean a fixed connection, a detachable connection, or an integral part; it can mean a mechanical connection, an electrical connection, a physical connection, or a wireless communication connection; it can mean a direct connection or an indirect connection through an intermediate medium; it can mean the internal connection of two components or the interaction between two components, unless otherwise explicitly limited. Those skilled in the art can understand the specific meaning of the above terms in this utility model according to the specific circumstances.

[0034] Furthermore, the technical solutions of the various embodiments of this utility model can be combined with each other, but only if they are based on the ability of those skilled in the art to implement them. When the combination of technical solutions is contradictory or cannot be implemented, it should be considered that such combination of technical solutions does not exist and is not within the scope of protection claimed by this utility model.

[0035] As attached Figure 1 -Appendix Figure 6As shown, this utility model provides a neutron source assembly 1 for a space reactor, used for start-up, shutdown, combustion control, and auxiliary combustion of the core assembly 2. The core assembly 2 includes a fuel zone II 21, a first reflector zone 22 located outside the fuel zone II 21, a second reflector zone 23 located above the fuel zone II 21, a third reflector zone 24 located below the fuel zone II 21, a gas chamber 25 located between the fuel zone II 21 and the third reflector zone 24, multiple control drums 26 located within the first reflector zone 22, a shielding zone 27 located outside the first reflector zone 23, and a power generation hot end zone 28 located at the upper ends of the second reflector zone 22 and the first reflector zone 23. The specific working principle of the core assembly 2 is based on existing technology. The space reactor neutron source assembly 1 includes a linear motion mechanism and a neutron source rod disposed at the output end of the linear motion mechanism. The linear motion mechanism can be any drive mechanism capable of linear reciprocating movement, such as a cylinder, hydraulic cylinder, or electric cylinder, or a combination of a motor and a linear reciprocating transmission mechanism. Any mechanism that meets the temperature requirements of the space reactor is acceptable. The neutron source rod can be a cylinder or a square prism, determined according to actual needs, with a cylindrical structure being preferred. The neutron source rod includes a neutron source functional area, a gap 17, and a cladding 18 arranged sequentially from the inside out. The neutron source functional area is used to control and assist combustion of the core assembly 2. The gap 17 facilitates the installation of the fuel area I 12 into the cladding 18 and also serves to contain fission gases and prevent irradiation swelling. The cladding 18 forms the neutron source rod into a whole, enabling the entire assembly to move.

[0036] The neutron source functional area includes a heat transfer zone 11, a fuel zone I 12, a separation zone I 13, a neutron source 14, a separation zone II 15, and a shutdown zone 16 arranged sequentially.

[0037] When the core assembly 2 is in the ignition and operating state, the heat transfer zone 11 serves as a supplement to the heat-conducting entity of the power generation hot end zone 28 when aligned with it. On one hand, it conducts heat from the power generation hot end zone 28, improving its heat homogenization effect. On the other hand, it directly conducts heat from the fuel zone I 12. Both work together to improve its heating temperature and heat uniformity, ultimately increasing power generation. Furthermore, when the fuel zone I 12 and fuel zone II 21 are aligned, the heat transfer zone 11 also blocks the heat conduction of the fuel zone I 12, preventing heat from escaping through the through-hole at the second reflector zone 22, and simultaneously preventing heat from the fuel zone I 12 from affecting the shielding zone 27 and burning it.

[0038] Fuel zone I12 is used to supplement fuel zone II21 after the core assembly 2 is in the ignition and operation state, thereby increasing the total amount of fuel and improving the combustion effect. This gives the space reactor sufficient backup reactivity. It can also adjust other functional zones such as fuel zone II21 (fuel enrichment), control drum 26 (orientation of control drum 26) and the position of fuel zone I12 (intersection degree between fuel zone I12 and fuel zone II21) according to the burnup situation to ensure the space reactor burnup critical heat release.

[0039] Separation zone I13 is used to physically separate neutron source 14 and fuel zone I12. On one hand, it insulates neutron source 14 and fuel zone I12 from heat transfer, preventing heat transfer from one of them to the non-operating parts during operation. This helps maintain neutron source 14 at a relatively low temperature, ensuring its performance stability and lifespan, while preventing fuel zone I12 from being subjected to unnecessary additional heat sources or localized overheating. On the other hand, it prevents direct physical contact between neutron source 14 and fuel zone I12, thus avoiding accidental overheating and damage.

[0040] Neutron source 14 is used to ignite and start the reactor core assembly 2. When the linear motion mechanism drives neutron source 14 to be located in the middle of fuel zone II 21 in the reactor core assembly 2, neutrons are continuously injected into the reactor core, and the space reactor achieves critical ignition.

[0041] Separation zone II 15 is used to physically separate neutron source 14 and shutdown zone 16. It can prevent shutdown zone 16 from being damaged, swollen or reduced in absorption efficiency due to overheating, and ensure its shutdown reliability under high burnup or emergency conditions. At the same time, it can also prevent shutdown zone 16 from interfering with the expected operating temperature of neutron source 14 and maintain the stability of its neutron yield.

[0042] The shutdown zone 16 is used to achieve reactor shutdown when it corresponds to fuel zone II 21 in core assembly 2. It can also be used to adjust the position of shutdown zone 16 and fuel zone II 21 to achieve reactivity regulation. Specifically, during shutdown, shutdown zone 16 absorbs neutrons in core assembly 2, causing the reactor to rapidly decrease to a subcritical state and the chain reaction to stop. When regulating reactivity, the position of fuel zone II 21 (fuel enrichment), control drum 26 (orientation of control drum 26), and shutdown zone 16 (degree of intersection between shutdown zone 16 and fuel zone II 21) can be adjusted according to burnup conditions to achieve appropriate reactivity regulation.

[0043] When the neutron source 14 in the neutron source rod driven by the linear movement mechanism is located in the middle of fuel zone II 21 in the core assembly 2, the core assembly 2 is ignited and started up. When the fuel zone I 12 in the neutron source rod driven by the linear movement mechanism corresponds to (including alignment or intersection) the fuel zone II 21 in the core assembly 2, the combustion of the core assembly 2 is enhanced. When the shutdown zone 16 in the neutron source rod driven by the linear movement mechanism corresponds to (including alignment or intersection) the fuel zone II 21 in the core assembly 2, the core assembly 2 is shut down or its reactivity is adjusted.

[0044] The space reactor neutron source assembly 1 provided by this invention makes better use of the crucial location at the reactor core center. It can move vertically up and down from the core center, featuring a simple and compact structure that efficiently performs functions such as fuel-assisted combustion, neutron source start-up, reactor shutdown, and reactivity regulation. Compared to existing neutron source regions that only provide reactor ignition, this invention achieves fuel-assisted combustion, reactor shutdown, and reactivity regulation without increasing circumferential dimensions, significantly improving the controllability of the reactor system.

[0045] In one embodiment, the height of fuel zone I 12 is the same as the height of fuel zone II 21 in core assembly 2. That is, when fuel zone I 12 and fuel zone II 21 are positioned correspondingly, the two ends of fuel zone I 12 can be aligned with the two ends of fuel zone II 21, thereby maximizing the replenishment of fuel zone II 21 and maximizing the auxiliary combustion effect.

[0046] In one embodiment, the height of the heat transfer zone 11 is consistent with the height of the power generation hot end zone 28 in the core assembly 2. Since the height of the fuel zone I 12 is consistent with the height of the fuel zone II 21 in the core assembly 2, when the fuel zone I 12 and fuel zone II 21 are aligned, the heat transfer zone 11 is also aligned with the power generation hot end zone 28, maximizing the heat transfer effect and increasing power generation. Preferably, the partition zone I 13 covers the through-holes of the gas chamber 25, the third reflection zone 24, and the shielding zone 27 in the core assembly 2 (the through-holes of the gas chamber 25 have inner walls, thus ensuring the closed state of the through-holes of the gas chamber 25). In this case, the partition zone I 13 can prevent thermal radiation from impacting the third reflection zone 24, preventing the material of the third reflection zone 24 from degrading due to long-term exposure to high temperatures. Simultaneously, it can also maintain the temperature at the through-holes of the gas chamber 25, the third reflection zone 24, and the shielding zone 27, eliminating thermal stress concentration points and improving the structural strength and integrity of the core assembly 2.

[0047] In one embodiment, the height of the partition region I 13, the neutron source 14, and the partition region II 15 is greater than or equal to the height of the core assembly 2;

[0048] When the neutron source 14 is located in the middle of fuel region II 21 in the core assembly 2 within the neutron source rod, the upper end of the partition region I 13 is flush with the upper end of the core assembly 2, or the upper end of the partition region I 13 protrudes from the upper end of the core assembly 2; the lower end of the partition region II 15 is flush with the lower end of the core assembly 2, or the lower end of the partition region II 15 protrudes from the lower end of the core assembly 2. In this embodiment, complete isolation of the neutron source 14 can be achieved. The partition regions I 13 and II 15 completely isolate the leakage path of the neutron source 14, reducing the amount of neutrons axially escaping from the core and improving neutron utilization.

[0049] In one embodiment, the height of the shutdown area 16 is greater than or equal to the height of the core assembly 2;

[0050] When the shutdown zone 16 in the neutron source rod is aligned with the fuel zone II 21 in the core assembly 2, the two ends of the shutdown zone 16 are flush with the two ends of the core assembly 2, or the two ends of the shutdown zone 16 protrude from the two ends of the core assembly 2. In this embodiment, axial complete absorption of neutrons can be achieved, effectively preventing neutron leakage. When the strong absorber of the shutdown zone 16 completely covers the core height, the path of neutron axial leakage from the top or bottom of the core is completely blocked.

[0051] In one embodiment, the heat transfer zone 11 is made of carbon nanotubes, which offer excellent thermal conductivity and lightweight properties, thus meeting the requirements for both thermal efficiency and lightweight design; and / or,

[0052] The core material of the fuel pellets in fuel zone I12 is UN, U 235 Enrichment level 65%; and / or,

[0053] The materials used for the partition zones I13 and II15 are Al2O3. The use of Al2O3 provides excellent thermal insulation and ultra-high temperature resistance; and / or,

[0054] The neutron source-14 material is Am-Be, which has a half-life of 458 years and is suitable for satellite operations, deep space, or distant-space missions; and / or,

[0055] The material used in the shutdown zone 16 is B4C, which has excellent neutron absorption properties and provides efficient shutdown control.

[0056] In one embodiment, the shell 18 is made of SS316L steel. SS316L steel offers good structural strength and corrosion resistance.

[0057] In one embodiment, the gap 17 can contain fission-generated gas. In this embodiment, the gap 17 serves as a container for the fission gas and can resist radiation swelling.

[0058] This utility model also provides a method for controlling a neutron source assembly in a space reactor, using the aforementioned space reactor neutron source assembly 1, including the following steps:

[0059] When it is necessary to ignite and start up the reactor core assembly 2, the neutron source 14 in the neutron source rod is driven by the linear movement mechanism to be located in the middle of the fuel zone II 21 in the reactor core assembly 2.

[0060] When it is necessary to enhance the combustion of core assembly 2, the fuel zone I12 in the neutron source rod is moved by the linear movement mechanism to adjust the position of fuel zone I12 and fuel zone II21 in core assembly 2. At least one of the following can be adjusted according to the burnup situation: fuel zone II21 (fuel enrichment), control drum 26 (orientation of control drum 26), and position of fuel zone I12 (intersection degree of fuel zone I12 and fuel zone II21) to ensure the reactor burnup critical heat release.

[0061] When it is necessary to shut down or adjust the reactivity of the core assembly 2, the shutdown zone 16 in the neutron source rod is moved by the linear movement mechanism to adjust the position of the shutdown zone 16 and the fuel zone II 21 in the core assembly 2. The position of the fuel zone II 21 (fuel enrichment), the control drum 26 (orientation of the control drum 26) and the shutdown zone 16 (intersection degree between the shutdown zone 16 and the fuel zone II 21) can be adjusted according to the burnup situation to ensure that the reactor is shut down or the reactivity is appropriately adjusted.

[0062] This invention also provides a reactor system, including a core assembly 2 and the aforementioned space reactor neutron source assembly 1. The core assembly 2 includes a fuel zone II 21, a first reflector zone 22 located outside the fuel zone II 21, a second reflector zone 23 located above the fuel zone II 21, a third reflector zone 24 located below the fuel zone II 21, a gas chamber 25 located between the fuel zone II 21 and the third reflector zone 24, multiple control drums 26 located within the first reflector zone 22, a shielding zone 27 located outside the first reflector zone 23, and a power generation hot end zone 28 located at the upper ends of the second reflector zone 22 and the first reflector zone 23. Furthermore, the power generation hot end zone 28, the second reflector zone 22, the fuel zone II 21, the gas chamber 25, the third reflector zone 24, and the shielding zone 27 are coaxially provided with through holes to allow the neutron source rod to move axially within the core assembly 2.

[0063] The above description is merely an embodiment and does not constitute any limitation on this utility model. Any person skilled in the art can make many possible variations, modifications, or alterations to the technical solution of this utility model without departing from its scope. Therefore, any simple modifications, equivalent changes, and alterations made to the above embodiments based on the technical essence of this utility model, without departing from its scope, should fall within the protection scope of this utility model.

Claims

1. A space reactor neutron source assembly characterized by, It includes a linear motion mechanism and a neutron source rod disposed at the output end of the linear motion mechanism. The neutron source rod includes a neutron source functional area, a gap (17) and a shell (18) arranged sequentially from the inside to the outside. The neutron source functional area includes a heat transfer zone (11), a fuel zone I (12), a separation zone I (13), a neutron source (14), a separation zone II (15), and a shutdown zone (16) arranged sequentially. When the neutron source (14) in the neutron source rod is located in the middle of fuel zone II (21) in the core assembly (2), the linear moving mechanism enables the core assembly (2) to ignite and start up. When the fuel zone I (12) in the neutron source rod corresponds to the fuel zone II (21) in the core assembly (2), the linear moving mechanism enhances the combustion of the core assembly (2). When the shutdown zone (16) in the neutron source rod corresponds to the fuel zone II (21) in the core assembly (2), the linear moving mechanism enables the core assembly (2) to shut down or adjust its reactivity.

2. The space reactor neutron source assembly of claim 1, wherein, The height of fuel zone I (12) is the same as the height of fuel zone II (21) in core assembly (2).

3. The space reactor neutron source assembly of claim 2, wherein, The height of the heat transfer zone (11) is consistent with the height of the power generation heat end zone (28) in the core assembly (2).

4. The space reactor neutron source assembly of claim 1, wherein, The heights of the partition region I (13), the neutron source (14), and the partition region II (15) are greater than or equal to the height of the core assembly (2); When the neutron source (14) in the neutron source rod is located in the middle of the fuel region II (21) in the core assembly (2), the upper end of the partition region I (13) is flush with the upper end of the core assembly (2) or the upper end of the partition region I (13) protrudes from the upper end of the core assembly (2); the lower end of the partition region II (15) is flush with the lower end of the core assembly (2) or the lower end of the partition region II (15) protrudes from the lower end of the core assembly (2).

5. The space reactor neutron source assembly of claim 1, wherein, The height of the shutdown area (16) is greater than or equal to the height of the core assembly (2); When the shutdown zone (16) in the neutron source rod corresponds to the fuel zone II (21) in the core assembly (2), the two ends of the shutdown zone (16) are flush with the two ends of the core assembly (2) or the two ends of the shutdown zone (16) protrude from the two ends of the core assembly (2).

6. The space reactor neutron source assembly of any of claims 1-5, wherein, The heat transfer zone (11) is made of carbon nanotube material; and / or, The fuel pellet core material of the fuel region I (12) uses UN, U 235 Enrichment 65%; and / or, The materials of the partition I (13) and partition II (15) are Al2O3; and / or, The neutron source (14) material is Am-Be; and / or, The material used in the shutdown area (16) is B4C.

7. The space reactor neutron source assembly of any of claims 1-5, wherein, The shell (18) is made of SS316L steel.

8. The space reactor neutron source assembly of any of claims 1-5, wherein, The gap (17) can contain the fission-generated gas.

9. A reactor system characterized by, It includes the core assembly (2) and the space reactor neutron source assembly (1) as described in any one of claims 1-8.

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