Vehicle-mounted liquid-based heat pipe micro-reactor power supply system

Abstract

The application discloses a kind of vehicle-mounted liquid base heat pipe micro reactor power supply systems, belong to vehicle-mounted nuclear reactor power supply and heat pipe cooling reactor system design technical field, system includes reactor core subsystem, control mechanism, heat transport subsystem, thermoelectric conversion subsystem, residual heat removal subsystem.Reactor core subsystem is provided with fuel rod, alkali metal high temperature heat pipe, liquid lead bismuth matrix, heat insulation layer, reflection layer, shielding layer, control rod and control drum;Heat transport subsystem is composed of multiple high-temperature alkali metal heat pipes, high-temperature alkali metal heat pipe evaporation section goes into the inside of core liquid lead bismuth matrix, condensation section is connected with thermoelectric conversion subsystem;Thermoelectric conversion subsystem is composed of heat transfer matrix, stirling generator;Residual heat removal subsystem hot end is connected with stirling generator, cold end connects compact plate-fin radiator, utilizes cooling water to carry out heat transport, and cooling water pump provides the power of cooling water circulation.

Description

Technical Field

[0001] This invention relates to the field of vehicle-mounted nuclear reactor power supply and heat pipe cooled reactor system design technology, specifically to a vehicle-mounted liquid-based heat pipe microreactor power supply system. Background Technology

[0002] Vehicle-mounted and land-based mobile micro nuclear reactors offer advantages such as high power density, long operating life, and strong environmental adaptability, making them suitable as independent energy supply devices for missions in remote areas, field exploration, emergency rescue, and mobile platforms. Heat pipe-cooled reactors utilize high-temperature alkali metal heat pipes to achieve passive transfer of core fission heat, featuring a highly compact structure, simple system, and inherently high safety, making them an important technological approach for vehicle-mounted mobile nuclear power sources.

[0003] However, conventional heat pipe microreactor designs generally suffer from two major engineering bottlenecks: First, during frequent start-ups and shutdowns or long-term high-temperature operation, the solid core substrate experiences significant differential thermal expansion between the solid substrate, fuel rods, and heat pipes, leading to a serious risk of mechanical crushing and breakage. Second, due to the extremely limited space on the vehicle platform, it is difficult to deploy the various subsystems, making it difficult to efficiently and uniformly transfer core fission heat to the downstream power generation end, and the high-power waste heat at the tail end is difficult to dissipate in the confined space. Therefore, there is an urgent need to propose a novel, highly integrated architecture: a vehicle-mounted liquid-based heat pipe microreactor power system that uses liquid lead-bismuth heat transfer medium (to eliminate core thermal stress and prevent corrosion), seamlessly exits with differentially sized direct heat pipes, uses a large-volume solid heat transfer substrate in the middle for temperature homogenization and coupling, and incorporates a rear-mounted Stirling generator and plate-fin water-cooled circulation for heat dissipation. Summary of the Invention

[0004] To address the problems existing in the prior art, the present invention aims to provide a vehicle-mounted liquid-based heat pipe microreactor power system. This system utilizes the fluidity of the liquid metal core to solve the thermal stress fatigue problem of all-solid-state structures under long-life, high-power operation. It achieves uniformity of the radial temperature field of the core through the efficient heat conduction of the liquid medium. Combined with a heat pipe array, a solid-state coupled heat transfer substrate, and an efficient Stirling converter and tail-end circulating water cooling module, it constructs a land-based mobile power system with intrinsic safety characteristics, excellent heat transfer performance, and a highly compact integration.

[0005] To achieve the above objectives, the present invention adopts the following technical solution: A vehicle-mounted liquid-based heat pipe microreactor power system includes: a reactor core subsystem 1, a control mechanism 3, a heat transport subsystem, a thermoelectric conversion subsystem, and a waste heat removal subsystem. The reactor core subsystem 1 is equipped with fuel rods 11, alkali metal high-temperature heat pipes 2, a liquid lead-bismuth substrate 13, an insulation layer 14, a reflective layer 16, a shielding layer 17, control rods 12, and a control drum 15. The control mechanism 3 drives the control rods 12 and the control drum 15. The heat transport subsystem consists of multiple alkali metal high-temperature heat pipes 2 extending from the reactor core subsystem 1. The evaporation section of the alkali metal high-temperature heat pipes 2 extends into the liquid lead-bismuth substrate 13 in the core, and the condensation section is connected to the thermoelectric conversion subsystem. The thermoelectric conversion subsystem consists of a heat transfer substrate 4 and a Stirling generator 5. The hot end 6 of the waste heat removal subsystem is connected to the Stirling generator, and the cold end is connected to a compact plate-fin heat exchanger 8, utilizing cooling water for heat transport. A cooling water pump 7 provides the power for cooling water circulation.

[0006] The fuel rod 11 and the alkali metal high-temperature heat pipe 2 are located in the core active region; the core active region is filled with liquid lead-bismuth matrix 13, which covers the fuel rod 11 and the alkali metal high-temperature heat pipe 2 for transferring heat between them.

[0007] The fuel rod 11 includes a fuel pellet, an air gap, and a cladding arranged sequentially from the inside out; the fuel pellet is a uranium nitride (UN) pellet; and the cladding is made of Mo-10Re alloy to prevent corrosion by liquid lead and bismuth.

[0008] The wall material of the alkali metal high-temperature heat pipe 2 is Mo-10Re alloy, and it has a dry-channel liquid wick inside, and the heat transfer medium is sodium. The reactor core active zone is surrounded by an insulation layer 14, which encloses the liquid lead-bismuth matrix 13 to prevent liquid lead-bismuth leakage and reduce heat loss. To prevent corrosion of the liquid metal, the insulation layer 14 is made of pure molybdenum (Mo) material.

[0009] The control rod 12 is used for emergency shutdown of the reactor; the control drum 15 is arranged around the outside of the hexagonal active core region, and the control drum 15 is configured with two different diameter sizes according to its position at the apex or each side of the hexagonal core; both the control rod 12 and the control drum 15 use boron carbide (B4C) as a neutron absorber.

[0010] One end of the heat transfer substrate 4 is heat exchanged with the condensation section of the alkali metal high-temperature heat pipe, and the hot ends of the multiple Stirling generators 5 are coupled to the other end of the heat transfer substrate 4 to convert the heat transferred by the alkali metal high-temperature heat pipe into electrical energy.

[0011] The compact plate-fin radiator 8 is composed of multiple layers of parallel stacked metal fins, with high specific surface area microchannels formed inside for cooling water flow; the cooling water pump 7 is a micro circulation pump connected in series in the cooling pipeline, used to drive the cooling water to perform forced convection heat exchange in the microchannels.

[0012] Compared with the prior art, the present invention has the following advantages: 1. This invention provides a vehicle-mounted liquid-based heat pipe microreactor power system. The reactor core system generates fission heat through fuel rods. The heat is efficiently transferred to the alkali metal high-temperature heat pipe using a liquid lead-bismuth matrix that does not require large-scale forced flow. After the alkali metal high-temperature heat pipe passes through the shielding module, the heat is directly introduced into the heat transfer matrix and converted into electrical energy by a tightly coupled Stirling generator. The unconverted waste heat is dissipated through a highly integrated compact plate-fin water-cooled heat exchanger at the tail end.

[0013] 2. During the heat transfer process, the static liquid lead-bismuth medium not only maintains the system's strong passivity, but also completely eliminates the solid-solid contact thermal resistance between components, effectively avoiding structural coupling damage caused by thermal expansion mismatch at high temperatures. At the same time, the extremely high boiling point of lead-bismuth provides the system with a large temperature safety margin and exhibits excellent core power and temperature distribution homogenization capabilities.

[0014] 3. This invention ultimately achieves a high degree of integration of fission heat generation, liquid-solid multi-state heat transfer, Stirling thermoelectric conversion, and circulating water cooling heat dissipation, and has the significant characteristics of high integration, extremely compact structure, and strong inherent operational safety. Attached Figure Description

[0015] To more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the accompanying drawings used in the description of the embodiments will be briefly introduced below. Obviously, the drawings described below are merely embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on the provided drawings without any creative effort.

[0016] Figure 1 A schematic diagram of the overall structure of a vehicle-mounted liquid-based heat pipe microreactor power system provided by the present invention; Figure 2 This is a schematic cross-sectional view of the reactor module provided by the present invention; Detailed Implementation

[0017] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0018] See Figure 1 This embodiment provides a vehicle-mounted liquid-based heat pipe microreactor power system, which is highly integrated within the confined space of a vehicle platform. The system mainly includes: a reactor core subsystem 1, a control mechanism 3, a heat transport subsystem, a thermoelectric conversion subsystem, and a waste heat removal subsystem. The reactor core subsystem 1 is located at the front end of the system and is used to generate fission heat; the heat transport subsystem is connected to the reactor core subsystem 1 and is used to passively transfer the generated fission heat to the rear structure; the thermoelectric conversion subsystem is located at the rear of the core and is used to efficiently convert the received heat into electrical energy; the waste heat removal subsystem is integrated at the rear end of the system and connected to the thermoelectric conversion subsystem, and is used to remove waste heat that has not been converted into electrical energy from the system.

[0019] like Figure 2 As shown, the reactor core subsystem 1 mainly includes fuel rods 11, alkali metal high-temperature heat pipes 2, liquid lead-bismuth substrate 13, insulation layer 14, reflective layer 16, shielding layer 17, control rods 12, and control drum 15.

[0020] In this reactor core, fuel rods 11 and alkali metal high-temperature heat pipes 2 are arranged in a staggered hexagonal array within the active region. The active region is filled with a liquid lead-bismuth matrix 13, which serves as a fluid heat transfer medium, completely enveloping the fuel rods 11 and alkali metal high-temperature heat pipes 2. During reactor operation, the fission heat generated by the fuel rods 11 is transferred to the alkali metal high-temperature heat pipes 2 through the liquid lead-bismuth matrix 13. The introduction of the liquid medium not only completely eliminates the solid-solid contact thermal resistance between components, significantly improving heat transfer capacity, but also perfectly absorbs the thermal expansion differences between components at high temperatures, preventing structural compression damage.

[0021] In this embodiment, the fuel rod 11 is composed of uranium nitride (UN) fuel pellets, a gas gap, and a cladding from the inside out. The gas gap is used to contain fission gases and buffer thermal expansion. To prevent corrosion from the external high-temperature liquid lead-bismuth matrix 13, the cladding is made of Mo-10Re alloy, which has excellent corrosion resistance.

[0022] The heat transport subsystem consists of 126 straight alkali metal high-temperature heat pipes 2, whose wall material is also Mo-10Re alloy. They have internal dry-channel wicks and are filled with sodium as the heat transfer medium. The evaporation section of the alkali metal high-temperature heat pipes 2 extends deep into the liquid lead-bismuth matrix 13 in the core active region. Specifically, to mitigate the power concentration effect on the outermost fuel rods caused by neutron reflection at the core edge, the alkali metal high-temperature heat pipes 2 are arranged in a segmented diameter configuration within the core active region: the outermost alkali metal high-temperature heat pipes have a diameter of 30 mm, while the innermost ones have a diameter of 20 mm. This differential diameter design precisely matches the high heat dissipation requirements of the periphery, effectively flattening the radial temperature field of the core.

[0023] The insulation layer 14 tightly covers the periphery of the active zone of the reactor core, encapsulating the liquid lead-bismuth matrix 13 to prevent liquid metal leakage and reduce radial heat loss. To resist corrosion, the insulation layer 14 is made of pure molybdenum (Mo). Outside the insulation layer 14, a reflective layer 16 and a shielding layer 17 are arranged sequentially, used to reduce neutron leakage to improve neutron utilization and to attenuate neutrons and gamma rays radiated towards rear equipment and the external environment, respectively.

[0024] Core reactivity control is achieved collaboratively by control mechanism 3, which drives control rods 12 and control drums 15. Control rods 12 are specifically designed for emergency shutdown during accident conditions; control drums 15 are positioned around the hexagonal active core region. To achieve the most compact arrangement within limited radial space, control drums 15 are innovatively configured with two different diameters, corresponding to either the apex or sides of the hexagonal core, perfectly fitting the hexagonal boundaries. Both control rods 12 and control drums 15 are filled with boron carbide (B4C) as a neutron absorber to ensure absolute safety and precision in reactivity regulation.

[0025] See also Figure 1 After the condensing section of the alkali metal high-temperature heat pipe 2 passes through the shielding layer 17, it is directly connected to the thermoelectric conversion subsystem. This thermoelectric conversion subsystem consists of a heat transfer substrate 4 and multiple Stirling generators 5. One end of the heat transfer substrate 4 is heat exchanged with the condensing sections of all the alkali metal high-temperature heat pipes 2, serving as an intermediate medium to collect and homogenize heat; the hot ends of the multiple Stirling generators 5 are tightly coupled to the other end of the heat transfer substrate 4, used to convert the absorbed heat into electrical energy through dynamic circulation.

[0026] The waste heat removal subsystem is highly integrated into the power system's tail end. The hot end 6 of the waste heat removal subsystem is connected to the cold end of the Stirling generator 5, and the cold end is connected to a compact plate-fin radiator 8. This compact plate-fin radiator 8 consists of multiple layers of parallel stacked metal fins, forming high specific surface area microchannels inside, providing a large heat exchange area within a very small volume. A cooling water pump 7, acting as a micro-circulation pump, is connected in series in the pipeline, providing closed-loop power to drive the cooling water through forced convection heat exchange within the microchannels of the Stirling generator 5 and the finned radiator 8, efficiently dissipating waste heat.

[0027] In this embodiment, the energy cycle workflow of the system is as follows: the fuel rod 11 generates fission heat, which is efficiently transferred to the evaporation section of the alkali metal high-temperature heat pipe 2 via the liquid lead-bismuth matrix 13; the heat is passively transported to the condensation section by the phase change of the sodium working fluid and introduced into the heat transfer matrix 4; the Stirling generator 5 absorbs the heat energy in the heat transfer matrix 4 and converts it into electrical energy for output; the unused waste heat is transported by the circulating cooling water to the compact plate-fin radiator 8 at the rear end and dissipated under the drive of the cooling water pump 7, thereby completing the safe, efficient, and compact energy conversion and heat dissipation closed loop of the entire vehicle power system.

[0028] The above description is merely a preferred embodiment of the present invention and is not intended to limit the scope of protection of the present invention. Any modifications, equivalent substitutions, and improvements made to the present invention within the spirit and principles of the present invention should be included within the scope of protection of the present invention.

Claims

1. A vehicle-mounted liquid-based heat pipe microreactor power system, characterized in that, include: The reactor core subsystem (1) includes a control mechanism (3), a heat transport subsystem, a thermoelectric conversion subsystem, and a waste heat removal subsystem. The reactor core subsystem (1) is equipped with fuel rods (11), alkali metal high-temperature heat pipes (2), a liquid lead-bismuth matrix (13), an insulation layer (14), a reflective layer (16), a shielding layer (17), control rods (12), and a control drum (15). The control mechanism (3) is used to drive the control rods (12) and the control drum (15). The heat transport subsystem consists of the reactor core subsystem (11). 1) It consists of multiple alkali metal high-temperature heat pipes (2) extending out. The evaporation section of the alkali metal high-temperature heat pipe (2) extends into the interior of the liquid lead-bismuth matrix (13). The condensation section of the alkali metal high-temperature heat pipe (2) is connected to the thermoelectric conversion subsystem. The thermoelectric conversion subsystem consists of a heat transfer matrix (4) and a Stirling generator (5). The hot end (6) of the waste heat discharge subsystem is connected to the Stirling generator (5), and the cold end is connected to a compact plate-fin heat exchanger (8). Cooling water is used for heat transport, and a cooling water pump (7) provides power for cooling water circulation.

2. The vehicle-mounted liquid-based heat pipe microreactor power system according to claim 1, characterized in that, The fuel rod (11) and the alkali metal high-temperature heat pipe (2) are located in the core active region; the core active region is filled with liquid lead-bismuth matrix (13), which covers the fuel rod (11) and the alkali metal high-temperature heat pipe (2) for transferring heat between them.

3. The vehicle-mounted liquid-based heat pipe microreactor power system according to claim 1, characterized in that, The fuel rod (11) includes a fuel pellet, an air gap and a cladding arranged sequentially from the inside to the outside; the fuel pellet is a uranium nitride pellet; and the cladding is made of Mo-10Re alloy to prevent corrosion by liquid lead bismuth.

4. The vehicle-mounted liquid-based heat pipe microreactor power system according to claim 1, characterized in that, The wall material of the alkali metal high-temperature heat pipe (2) is Mo-10Re alloy, and it has a dry-channel liquid wick inside, and the heat transfer medium is sodium.

5. The vehicle-mounted liquid-based heat pipe microreactor power system according to claim 1, characterized in that, The alkali metal high-temperature heat pipes (2) are arranged in sections with different diameters in the active region of the reactor core: the diameter of the alkali metal high-temperature heat pipes arranged in the outermost ring is enlarged to 30 mm, while the diameter of the alkali metal high-temperature heat pipes arranged in the inner ring is 20 mm.

6. The vehicle-mounted liquid-based heat pipe microreactor power system according to claim 1, characterized in that, The reactor core active zone is surrounded by an insulation layer (14), which wraps the liquid lead-bismuth matrix (13) to prevent liquid lead-bismuth leakage and reduce heat loss; to prevent liquid metal corrosion, the insulation layer (14) is made of pure molybdenum material.

7. The vehicle-mounted liquid-based heat pipe microreactor power system according to claim 1, characterized in that, The control rod (12) is used for emergency shutdown of the reactor; the control drum (15) is arranged around the outside of the hexagonal active core area, and the control drum (15) is configured with two different diameter sizes according to its position at the apex or each side of the hexagonal core; both the control rod (12) and the control drum (15) use boron carbide (B4C) as a neutron absorber.

8. The vehicle-mounted liquid-based heat pipe microreactor power system according to claim 1, characterized in that, One end of the heat transfer substrate (4) is heat exchanged with the condensation section of the alkali metal high-temperature heat pipe, and the hot ends of the multiple Stirling generators (5) are coupled to the other end of the heat transfer substrate (4) to convert the heat transferred by the alkali metal high-temperature heat pipe into electrical energy.

9. The vehicle-mounted liquid-based heat pipe microreactor power system according to claim 1, characterized in that, The compact plate-fin radiator (8) is composed of multiple parallel stacked metal fins, and has a high specific surface area microchannel for cooling water flow inside; the cooling water pump (7) is a micro circulation pump connected in series in the cooling pipeline, used to drive the cooling water to perform forced convection heat exchange in the microchannel.

Images