A high-efficiency passive heat exchange system for high-power steady-state operation of a fusion reactor

Abstract

This invention discloses a high-efficiency passive heat exchange system for high-power steady-state operation of a fusion reactor. The system includes a first wall component, a vacuum heat pipe assembly, arrayed fins, and a heat exchange assembly. The heat pipe assembly includes a heat pipe shell, a gradient pore layer, and a vacuum insulation layer, and is divided into an internal heat absorption section, an insulation section, and a heat exchange section along the heat transfer path. The average pore diameter of the gradient pore layer gradually increases from the internal heat absorption section to the heat exchange section. In the internal heat absorption section, the heat pipe shell is connected to the first wall component, and the low-boiling-point working fluid in the heat pipe shell vaporizes and carries away the fusion heat. In the insulation section, a vacuum insulation layer is provided on the outside of the heat pipe shell to ensure effective heat transfer to the heat exchange section. In the heat exchange section, the heat pipe shell is connected to the arrayed fins and placed in the heat exchange assembly. The gaseous working fluid in the heat pipe shell is cooled and liquefied by the cooling medium disturbed by the flow disruptor in the heat exchange assembly, and then flows back to the internal heat absorption section through the gradient pore layer. This system has high cooling efficiency and a simple structure.

Description

Technical Field

[0001] This invention relates to the field of thermal control technology for nuclear fusion devices, specifically to a high-efficiency passive heat exchange system for high-power steady-state operation of fusion reactors. Background Technology

[0002] Under high-power, long-pulse operation conditions, nuclear fusion reactors face challenges exceeding 10 MW / m². 2 The high heat flux generated by fusion reactions requires cooling systems with excellent cooling capabilities. However, existing active cooling systems have significant limitations in meeting this challenge and are unable to effectively meet the cooling requirements of fusion reactors.

[0003] First, existing active cooling systems rely on the circulation of coolant to remove heat, and their cooling effect is limited by multiple factors such as coolant flow rate and thermal properties. Under high heat load environments, coolant flow rate and heat transfer efficiency are often insufficient, resulting in the inability to effectively absorb and transfer the large amount of heat generated. Especially in high heat flux areas such as the first wall components, traditional cooling systems cannot provide sufficient thermal management capabilities, easily leading to component overheating, and in severe cases, even ablation, endangering the operational safety of the fusion reactor.

[0004] Secondly, existing cooling technologies generally suffer from complex structures, large size, and heavy weight. These systems typically require high-power pumping equipment and lengthy piping networks to maintain coolant flow, leading to increased energy consumption throughout the cooling system. In the high-energy-density and extremely safety-critical environment of fusion reactors, overly complex cooling systems not only increase the size and weight of the equipment but also make system maintenance and operation more difficult and expensive.

[0005] Most critically, traditional cooling systems lack long-term stability under extreme conditions. In the high-irradiation, high-temperature, and high-vacuum environment of a fusion reactor, existing forced-flow cooling technology is prone to high-pressure coolant leakage accidents. Once such an accident occurs, it will jeopardize the safety and long-term stable operation of the fusion reactor.

[0006] Therefore, existing cooling technologies cannot meet the heat dissipation requirements of nuclear fusion reactors under high heat loads and extreme environments, necessitating a simpler, more efficient, and long-term stable cooling system. This system must not only achieve effective heat dissipation under high heat loads but also operate stably in the harsh environments of deuterium-tritium fusion reactors, including high temperatures, intense radiation, and high vacuum, preventing coolant leakage and reducing system maintenance costs. Summary of the Invention

[0007] The purpose of this invention is to fill the gap in existing technology and provide a highly efficient passive heat exchange system for high-power steady-state operation of fusion reactors. The main technical solution is as follows:

[0008] A high-efficiency passive heat exchange system for high-power steady-state operation of a fusion reactor includes a first wall component, a vacuum heat pipe assembly, arrayed fins, and a heat exchange assembly. The vacuum heat pipe assembly includes a heat pipe shell, a gradient pore layer, and a vacuum insulation layer. The vacuum heat pipe assembly is divided into an internal heat absorption section, an insulation section, and a heat exchange section along the heat transfer path.

[0009] As a preferred embodiment of the present invention, the vacuum heat pipe assembly is arranged at an upward angle from the heat absorption section to the heat exchange section inside the main unit.

[0010] As a preferred embodiment of the present invention, the average pore diameter of the gradient pore layer gradually increases from the heat absorption section inside the host to the heat exchange section.

[0011] As a preferred embodiment of the present invention, the heat-conducting tube shell is made of a metallic material with high thermal conductivity and good thermal stability and anti-tritium embrittlement performance in the deuterium-tritium fusion environment. The material includes, but is not limited to, chromium-zirconium-copper alloy, molybdenum alloy and tungsten-based alloy.

[0012] As a preferred embodiment of the present invention, the heat-conducting pipe shell contains a low-boiling-point medium whose physical properties are suitable for withstanding a heat flux density greater than 10 MW / m² in the first wall component of a fusion reactor. 2 It operates under specific conditions and features high latent heat and low vapor pressure.

[0013] As a preferred embodiment of the present invention, in the heat absorption section inside the host, the heat-conducting pipe shell is connected to the first wall component through an oxygen-free copper transition layer, and a metallurgical bond is formed by hot isostatic diffusion welding.

[0014] As a preferred embodiment of the present invention, the temperature of the first wall component rises under the high heat flux heat radiation generated by fusion, causing the low boiling point heat transfer medium in the heat-conducting tube shell connected to the first wall component to vaporize and absorb heat.

[0015] As a preferred embodiment of the present invention, in the heat insulation section, the vacuum heat insulation layer is provided on the outer side of the heat-conducting pipe shell.

[0016] In a preferred embodiment of the present invention, the vacuum heat pipe assembly is connected to the heat exchange assembly in the heat exchange section. Within the heat exchange assembly, the heat pipe shell is connected to the array fins.

[0017] As a preferred embodiment of the present invention, the heat exchange assembly includes a vacuum jacket, a cooling medium, a cooling medium inlet and a high-pressure steam outlet, a baffle and a drive motor.

[0018] As a preferred embodiment of the present invention, the drive motor drives the baffle to rotate, causing the cooling medium on the array fins connected to the heat-conducting tube shell in the heat exchange assembly to flow rapidly, thereby effectively enhancing the heat exchange performance.

[0019] Beneficial effects:

[0020] The present invention provides a high-efficiency passive heat exchange system for high-power steady-state operation of fusion reactors, which has the following advantages compared with the prior art:

[0021] This invention constructs a vacuum heat pipe heat exchange channel based on a low-boiling-point working fluid phase change mechanism. Heat transfer is achieved through a natural circulation process driven by evaporation and condensation, requiring no external pumping or energy input, and can achieve heat transfer rates greater than 10 MW / m³. 2 The continuous cooling and heat dissipation under heat flux density environment effectively solves the problems of low heat dissipation efficiency, high energy consumption and system complexity of traditional forced flow cooling systems in the high heat load area of ​​the first component of fusion reactor.

[0022] This invention constructs a gradient pore layer on the inner wall of a heat pipe, with the average pore diameter gradually increasing along the heat conduction path. Specifically, micropores are arranged in the heat absorption section of the main unit to enhance capillary drive and thus prevent drying out; while large-diameter pore channels are arranged in the heat exchange section to accelerate liquid return, thereby significantly improving the rewetting speed and overall liquid return capacity of the gradient pore layer, solving the common drying failure problem of ordinary heat pipes under high heat load.

[0023] The heat-conducting tube shell material used in this invention is a metallic material with high thermal conductivity, resistance to tritium embrittlement, and excellent irradiation stability, including but not limited to chromium-zirconium-copper, molybdenum alloys, and tungsten-based alloys. It exhibits good compatibility with the high-temperature, high-energy neutron irradiation and tritium permeation environment of nuclear fusion, significantly enhancing the operational safety and material service life of the entire heat exchange system. Furthermore, an oxygen-free copper transition layer is provided between the heat-conducting tube shell and the first wall component in the heat-absorbing section of the main unit, and a metallurgical connection is achieved using hot isostatic diffusion welding technology. This avoids the increase in thermal resistance and structural failure caused by poor contact or thermal cycling stress in traditional mechanical assembly connections, ensuring stable thermal conductivity under high heat flux conditions.

[0024] The vacuum heat pipe of the present invention has a vacuum insulation section in the heat transfer area, which can effectively reduce heat loss and thus efficiently transfer fusion energy to the heat exchange components for utilization.

[0025] Compared to traditional active cooling systems, this invention features a compact structure, simplified components, and high system reliability. It significantly reduces the use of pumps, valves, sensors, and complex piping networks, thereby lowering system complexity and potential failure risks from the outset. It is particularly suitable for the space-constrained, high-irradiation, and maintenance-restricted internal environments of fusion reactors. Furthermore, this invention employs a completely passive operating mechanism, with the low-boiling-point working fluid enclosed within the heat-conducting shell. No external driving force is required to create a high-pressure flow, thus eliminating the risk of high-pressure cooling medium leakage. It exhibits excellent long-term operational stability and low maintenance requirements, making it especially suitable for the high-reliability heat dissipation needs of critical fusion reactor components under long-pulse or steady-state operating conditions. Attached Figure Description

[0026] To more clearly illustrate the technical solutions of the embodiments of the present invention, the accompanying drawings of the embodiments will be briefly described below.

[0027] Figure 1 A schematic diagram of a high-efficiency passive heat exchange system for high-power steady-state operation of a fusion reactor provided by the present invention;

[0028] Figure 2 A schematic diagram of the structure of a vacuum heat pipe assembly in a high-efficiency passive heat exchange system for high-power steady-state operation of a fusion reactor, provided by the present invention;

[0029] Figure 3 This invention provides a schematic diagram of the structure of a heat exchange component in a high-efficiency passive heat exchange system for high-power steady-state operation of a fusion reactor.

[0030] Figure 4 This is a front structural diagram of the first wall component resistant to high heat flux.

[0031] Figure 5 This is a schematic diagram of the back structure of the first wall component resistant to high heat flux.

[0032] Figure 6 Simulation diagram of heat flow optimization for the first wall component with high heat flux resistance.

[0033] Figure 7 This is a schematic diagram of the straight section of a vacuum heat pipe.

[0034] Figure 8 This is a schematic diagram of the inclined section of a vacuum heat pipe.

[0035] Figure 9 This is a schematic diagram of the gradient pore layer.

[0036] Figure label:

[0037] 1. First wall component; 101. Separating chamber; 2. Vacuum heat pipe assembly; 201. Heat pipe shell; 202. Gradient pore layer; 203. Vacuum insulation layer; 210. Heat absorption section inside the main unit; 211. Insulation section; 212. Heat exchange section; 213. Connecting pipe; 3. Array fins; 4. Heat exchange assembly; 401. Vacuum jacket; 402. Cooling medium; 403. Cooling medium inlet; 404. High-pressure steam outlet; 405. Baffle; 406. Drive motor; 5. Low boiling point medium. Detailed Implementation

[0038] Embodiments of the present invention are described in detail below. Examples of these embodiments are shown in the accompanying drawings, wherein the same or similar reference numerals denote the same or similar elements or elements having the same or similar functions throughout. The embodiments described below with reference to the accompanying drawings are exemplary and are only used to explain the present invention, and should not be construed as limiting the present invention.

[0039] In the description of this invention, it should be understood that the orientation descriptions, such as up, down, front, back, left, right, etc., are based on the orientation or positional relationship shown in the accompanying drawings. They are only for the convenience of describing this invention and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limiting this invention.

[0040] In the description of this invention, unless otherwise explicitly defined, terms such as "set," "place," "assemble," and "connect" should be interpreted broadly, and those skilled in the art can reasonably determine the specific meaning of the above terms in this invention in conjunction with the specific content of the technical solution.

[0041] Example:

[0042] Please refer to the following: Figures 1 to 3 The present invention will now describe an efficient passive heat exchange system for high-power steady-state operation of a fusion reactor.

[0043] like Figures 1 to 3 As shown in the figure, an efficient passive heat exchange system for high-power steady-state operation of a fusion reactor according to an embodiment of the present invention includes a first wall component 1, a vacuum heat pipe assembly 2, arrayed fins 3, and a heat exchange assembly 4. The vacuum heat pipe assembly 2 includes a heat pipe shell 201, a gradient pore layer 202, and a vacuum insulation layer 203. The vacuum heat pipe assembly 2 is divided into a heat absorption section 210, an insulation section 211, and a heat exchange section 212 within the main unit along the heat transfer path.

[0044] like Figure 4 and Figure 5As shown in the figure, the structure and connection relationship between the first wall component and the heat-conducting tube shell in a high-efficiency passive heat exchange system for high-power steady-state operation of a fusion reactor according to an embodiment of the present invention are as follows: The first wall component 1 is composed of several partitioned chambers 101 arranged side by side, and each partitioned chamber 101 is connected to the heat-conducting tube shell 201 through a connecting pipe 213; a low-boiling-point medium 5 circulates between the first wall component 1 and the heat-conducting tube shell, and further, the low-boiling-point medium 5 is a liquid metal, such as NaK or liquid sodium.

[0045] like Figure 6 As shown in the figure, a simulation of heat flow optimization between the first wall component and the heat transfer tube shell in a high-efficiency passive heat exchange system for high-power steady-state operation of a fusion reactor according to an embodiment of the present invention is presented. The simulation results show that the temperature of the heat flow ranges from 300K to 735K. This temperature distribution indicates that at 10 MW / m 2 Under thermal load, the system suppresses the peak temperature of the first wall below 735K through the phase change endothermic reaction of the low-boiling-point working fluid 5 and the directional flow of the gradient porous layer 202, while maintaining the outlet temperature of the heat exchange section 212 ≤350K. This temperature control capability ensures that the first wall material maintains its creep resistance (recrystallization temperature of tungsten-based alloy >1473K) under fusion neutron irradiation, and that the cooling medium 402 has no risk of decomposition.

[0046] like Figure 7 As shown, Figure 7 This is a schematic diagram of the straight section of a vacuum heat pipe, with different sections connected externally by flange structures.

[0047] like Figure 8 As shown, Figure 8 This is a schematic diagram of the inclined section of the vacuum heat pipe assembly 2. The vacuum heat pipe assembly 2 is arranged obliquely upward along the spatial direction from the heat absorption section 210 to the heat exchange section 212 inside the main unit. This inclined structure design, combined with the assistance of gravity, effectively enhances the reflux capacity of the low-boiling-point medium 5 after condensation within the gradient pore layer 202.

[0048] like Figure 9 As shown, Figure 9 The diagram shows the structure of the gradient pore layer. For example, it can be divided into two types according to the different ways of bonding with the pipe wall: wire mesh liquid absorber and sintered liquid absorber. The wire mesh liquid absorber is bonded to the inner side of the pipe wall by adhesive, and the sintered liquid absorber is bonded to the inner side of the pipe wall by sintering. The minimum pore size of the gradient pore layer in the heat insulation section 211 is about 10 μm, and the maximum pore size of the gradient pore layer in the heat exchange section 212 is about 200 μm.

[0049] The working principle of the high-efficiency passive heat exchange system for high-power steady-state operation of fusion reactors disclosed in this invention is as follows:

[0050] For example, the heat-absorbing section 210 inside the fusion reactor is located inside the reactor and connected to the first wall component 1. When a high-power deuterium-tritium fusion reaction occurs, a large amount of heat energy is transferred to the first wall component 1 through thermal radiation and then to the heat-conducting shell 201 through thermal conduction. The heat-conducting shell 201 is made of a material with high thermal conductivity and stable properties under deuterium-tritium fusion conditions, so heat can be transferred well to the heat-conducting shell 201, thereby causing the low-boiling-point medium 5 inside the heat-conducting shell 201 to vaporize rapidly. After absorbing heat through a phase change in the heat-absorbing section 210 inside the reactor, the low-boiling-point medium 5 carries the heat in gaseous form along the layout path of the vacuum heat-conducting pipe assembly 2 to the heat exchange section 212. During heat transfer, a vacuum insulation layer 203 is provided on the outside of the heat-conducting pipe shell 201 in the insulation section 211. This significantly reduces heat loss caused by convection on the outer wall of the heat-conducting pipe shell 201, thereby ensuring that the heat from the heat-absorbing section 210 inside the main unit is effectively transferred to the heat exchange section 212, improving the system's heat transfer efficiency. The heat-conducting pipe shell 201 of the heat exchange section 212 is connected to the array fins 3 and placed inside the heat exchange assembly 4. Cooling medium 402 is supplied to the heat exchange assembly 4 through the cooling medium inlet 403 at the bottom to immerse the heat-conducting pipe shell 201 and the array fins 3 inside the heat exchange assembly 4. At the same time, the drive motor 406 drives the baffle 405 to rotate, increasing the convective heat transfer coefficient between the cooling medium 402 and the array fins 3, thereby achieving sufficient heat exchange. After the heat pipe shell 201 is cooled, its temperature decreases, causing the gaseous low-boiling-point medium 5 inside the heat pipe shell 201 to liquefy and release heat. The liquefied low-boiling-point medium 5, under the capillary force of the gradient pore layer 202, flows back to the heat absorption section 210 inside the main unit for the next phase change cycle heat transfer. This cycle repeats continuously, forming a closed, continuous, self-circulating heat exchange loop that does not require external pumps. Meanwhile, the cooling medium 402 inside the heat exchange component 4 absorbs heat and vaporizes into high-pressure steam, which escapes from the high-pressure steam outlet 404 for downstream thermal energy conversion, thereby realizing the utilization of fusion energy.

[0051] For example, the heat pipe shell 201 is provided with a gradient pore layer 202 inside. The average pore diameter of this gradient pore layer gradually increases from the heat absorption section 210 to the heat exchange section 212 inside the main unit, forming a capillary structure with a spatial gradient distribution. On the side near the heat absorption section 210 inside the main unit, the gradient pore layer 202 adopts a small pore size microstructure to provide strong capillary force, which can effectively draw in the liquid low-boiling-point medium 5, ensuring its continuous liquid supply under high heat flux density and suppressing capillary drying. Along the insulation section 211 to the heat exchange section 212, the pores gradually enlarge, reaching the maximum pore size at the heat exchange section, so as to reduce the backflow resistance and improve the backflow efficiency of the liquid medium. This gradient pore structure has both high capillary driving force and good backflow smoothness, breaking through the limitation of insufficient liquid supply of traditional homogeneous capillary structures, significantly improving the phase change heat efficiency of the low-boiling-point medium 5 inside the heat pipe shell 201, and ensuring that the first wall component 1 of the system in the fusion reactor exceeds 10 MW / m2 It can still be cooled stably and efficiently under extremely high heat flux density conditions.

[0052] For example, the heat pipe shell 201 is made of a metallic material with high thermal conductivity, resistance to tritium embrittlement, and excellent irradiation stability, including but not limited to chromium-zirconium-copper, molybdenum alloys, and tungsten-based alloys. It has good compatibility with the high temperature, high-energy neutron irradiation, and tritium permeation environment of nuclear fusion, significantly enhancing the operational safety and material service life of the entire heat exchange system. Furthermore, an oxygen-free copper transition layer is provided between the heat pipe shell 201 in the heat absorption section 210 of the main unit and the first wall component 1, and a metallurgical connection is achieved using hot isostatic diffusion welding technology. This avoids the increase in thermal resistance and structural failure caused by poor contact or thermal cycle stress in traditional mechanical assembly connections, ensuring stable thermal conductivity under high heat flux conditions.

[0053] For example, to further improve the reflux efficiency of the liquid low-boiling-point medium 5 in the heat-conducting pipe shell 201, the vacuum heat-conducting pipe assembly 2 is arranged obliquely upwards along the spatial direction from the heat absorption section 210 to the heat exchange section 212 inside the main unit. This oblique structure design, combined with the assistance of gravity, effectively enhances the reflux capability of the condensed low-boiling-point medium 5 in the gradient pore layer 202, ensuring that the vacuum heat-conducting pipe assembly 2 can still stably achieve heat circulation and transfer even with long-distance deployment. At the same time, this arrangement can also avoid the local stagnation of the condensed low-boiling-point medium 5 in the heat exchange section 212, preventing a decrease in heat exchange efficiency.

[0054] For example, in the heat insulation section 211 region, a vacuum insulation layer 203 is provided on the outside of the heat pipe shell 201. This vacuum insulation layer 203 is used to isolate the heat pipe shell 201 from the external environment, significantly reducing heat loss, thereby effectively ensuring that the heat carried in the heat pipe shell 201 is efficiently transferred from the heat absorption section 210 in the main unit to the heat exchange section 212, improving the overall heat transfer efficiency of the system.

[0055] For example, to enhance the heat exchange effect of the cooling medium 402 in the heat exchange component 4, the arrangement and structure of the array fins 3 can be optimized, or the array fins 3 can be made of a material with high thermal conductivity.

[0056] For example, the heat exchange assembly 4 is equipped with a drive motor 406 to drive the baffle 405 to agitate the cooling medium 402, thereby effectively increasing the convective heat transfer coefficient between the cooling medium 402 and the array fins 3, thereby achieving rapid and efficient heat exchange.

[0057] For example, the heat exchange assembly 4 employs a vacuum jacket 401, which significantly reduces the loss of heat absorbed by the cooling medium 402 within the heat exchange assembly 4, thereby ensuring the efficient collection of fusion energy.

[0058] The above description is only a preferred embodiment of the present invention. It should be noted that for those skilled in the art, several improvements and substitutions can be made without departing from the technical principles of the present invention, and these improvements and substitutions should also be considered within the scope of protection of the present invention.

Claims

1. A high-efficiency passive heat exchange system for high-power steady-state operation of a fusion reactor, characterized in that, It includes a first wall component (1), a vacuum heat pipe assembly (2), array fins (3), and a heat exchange assembly (4); the vacuum heat pipe assembly (2) includes a heat pipe shell (201), a gradient pore layer (202), and a vacuum insulation layer (203); the vacuum heat pipe assembly (2) is divided into a heat absorption section (210), an insulation section (211), and a heat exchange section (212) along the heat transfer path. The average pore diameter of the gradient pore layer (202) gradually increases from the heat absorption section (210) inside the host to the heat exchange section (212); The heat exchange assembly (4) includes a vacuum jacket (401), a cooling medium (402), a cooling medium inlet (403), a high-pressure steam outlet (404), a baffle (405), and a drive motor (406). The drive motor (406) drives the turbulence generator (405) to rotate, causing the cooling medium (402) on the array fins (3) connected to the heat pipe shell (201) in the heat exchange assembly (4) to flow rapidly, thereby effectively enhancing the heat exchange performance.

2. The high-efficiency passive heat exchange system for high-power steady-state operation of a fusion reactor according to claim 1, characterized in that, The vacuum heat pipe assembly (2) is arranged at an upward angle from the heat absorption section (210) to the heat exchange section (212) inside the main unit.

3. The high-efficiency passive heat exchange system for high-power steady-state operation of a fusion reactor according to claim 1, characterized in that, The heat-conducting tube shell (201) is made of a tritium-resistant brittle metal material, including chromium-zirconium-copper alloy, molybdenum alloy or tungsten-based alloy.

4. The high-efficiency passive heat exchange system for high-power steady-state operation of a fusion reactor according to claim 1, characterized in that, The heat-conducting tube shell (201) is encapsulated with a low-boiling-point medium (5), suitable for heat flux densities greater than 10 MW / m³. 2 fusion environment.

5. The high-efficiency passive heat exchange system for high-power steady-state operation of a fusion reactor according to claim 1, characterized in that, In the heat absorption section (210) inside the host, the heat-conducting tube shell (201) is connected to the first wall component (1) through an oxygen-free copper transition layer and is formed by hot isostatic diffusion welding.

6. The high-efficiency passive heat exchange system for high-power steady-state operation of a fusion reactor according to claim 1, characterized in that, In the heat insulation section (211), the vacuum insulation layer (203) is provided on the outside of the heat-conducting pipe shell (201).

7. The high-efficiency passive heat exchange system for high-power steady-state operation of a fusion reactor according to claim 1, characterized in that, In the heat exchange section (212), the vacuum heat pipe assembly (2) is connected to the heat exchange assembly (4); inside the heat exchange assembly (4), the heat pipe shell (201) is connected to the array fins (3).

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