Integrated heat exchange module for closed brayton cycle

Abstract

The application provides an integrated heat exchange module for closed Brayton cycle, comprising a pressure-bearing shell and an integrated heat exchanger unit. The pressure-bearing shell has multiple sets of first working medium flange interfaces, including a waste heat gas outlet flange and a first multi-channel integrated flange; the integrated heat exchanger unit comprises first, second and third heat exchangers, the second and third heat exchangers form an integrated cooling structure, the integrated heat exchanger unit is provided with a waste heat gas inlet flange and a second multi-channel integrated flange for collecting gas side inlets and outlets. The two sets of flange interfaces are directly connected and fastened to realize the sealed connection of the working medium flow path, replacing the traditional dispersed pipeline. The module has compact structure, reduces the number of pipelines and significantly saves space; meanwhile, the local resistance of the elbow pipe is eliminated, the system efficiency is improved; and the module is convenient to assemble and disassemble, supporting the overall modularization, rapid assembly and maintenance. The application provides an efficient and compact heat and power conversion integrated solution for advanced nuclear energy and space power systems.

Description

Technical Field

[0001] This invention belongs to the field of advanced nuclear energy technology and relates to an integrated heat exchange module for closed Brayton cycle. Background Technology

[0002] In the fields of advanced nuclear energy (such as high-temperature gas-cooled reactors) and space propulsion systems for small, modular applications, closed Brayton cycles (such as those using helium or supercritical carbon dioxide as the working fluid) are considered ideal solutions for achieving efficient heat-to-work conversion. However, these cycles face an inherent trade-off between system compactness and heat exchange efficiency in their design. This is especially true for mobile or compact reactors with thermal power in the MW range or even higher, where miniaturization and mobility impose extremely stringent requirements on the spatial dimensions of all subsystems, including the power conversion system. Among these, heat exchangers (such as regenerators, precoolers, and heaters), as the core equipment for heat-to-work conversion, account for a particularly significant portion of the volume. Therefore, effectively reducing the physical size of heat exchangers and optimizing their integration are crucial objectives that must be achieved.

[0003] Traditional solutions typically employ a split-type pipe flange connection method, arranging the heat exchanger separately from the main equipment such as the turbine and compressor. This approach not only requires individual end caps, inlet and outlet pipes, and corresponding connecting pipes for each heat exchanger, but also necessitates reserving flange interfaces and installation space on the main equipment. This results in a loose overall system structure, a large footprint, and further exacerbates the problem of the bulky heat exchanger size, making it difficult to meet the integration requirements within a limited volume. Furthermore, during the recovery process, the high-temperature waste heat gas generated by the power unit flows through multiple bends and local inlet and outlet structures, causing significant local pressure losses. This, combined with the increased heat dissipation due to the system's large size, further reduces the overall heat-to-work conversion efficiency of the power unit.

[0004] Therefore, breaking through the limitations of traditional split-connection architecture and developing new heat exchanger arrangements and connection schemes that are highly integrated, compact, and have low flow losses has become a decisive technological challenge in promoting the coordinated development of closed Brayton cycle systems in advanced nuclear energy and aerospace fields, achieving "miniaturization, modularization, and high efficiency." Addressing this challenge is the only way to unlock the efficiency potential of the core components of the thermodynamic cycle and ultimately achieve a leapfrog improvement in the heat-to-work conversion efficiency of power plants. Therefore, the breakthroughs and application effectiveness of this technology will largely determine the future technological landscape and core competitiveness of related high-end equipment industries.

[0005] It should be noted that the above introduction to the technical background is only for the purpose of providing a clear and complete explanation of the technical solutions of this application and facilitating understanding by those skilled in the art. It should not be assumed that these technical solutions are known to those skilled in the art simply because they have been described in the background section of this application. Summary of the Invention

[0006] In view of the shortcomings of the prior art described above, the purpose of this invention is to provide an integrated heat exchange module for closed Brayton cycles, which solves the problems of loose connection structure, large space occupation, and difficulty in meeting the integration requirements of limited volume in traditional split-type modules, thereby improving the heat-work conversion efficiency of power equipment.

[0007] To achieve the above and other related objectives, the present invention provides an integrated heat exchange module for a closed-loop Brayton cycle, comprising:

[0008] Pressure-bearing housing, which is used to form the pressure-bearing structure of a closed Brayton cycle power plant;

[0009] The first working fluid flange interface group is disposed on the outer wall of the pressure-bearing shell, and the first working fluid flange interface group includes a waste heat gas outlet flange and a first multi-channel integrated flange.

[0010] At least one set of integrated heat exchanger units, the integrated heat exchanger unit including a first heat exchanger, a second heat exchanger and a third heat exchanger; the second heat exchanger and the third heat exchanger are connected in series on the circulating cooling medium side to form an integral cooling unit; the outlet of the first heat exchanger is connected to the inlet of the second heat exchanger;

[0011] The second working fluid flange interface group is located on the integrated heat exchanger unit and is correspondingly arranged with the first working fluid flange interface group. The second working fluid flange interface group includes a waste heat gas inlet flange and a second multi-channel integrated flange. The waste heat gas inlet flange is arranged at the inlet of the first heat exchanger, and the second multi-channel integrated flange is arranged on the gas side of the integrated cooling unit to serve as the docking interface for the gas side inlet and outlet of the integrated cooling unit.

[0012] The first working fluid flange interface group and the corresponding flanges in the second working fluid flange interface group are directly attached and fastened through the flange sealing surface, thereby directly connecting the structure between the pressure shell and the integrated heat exchanger unit and integrating them into a compact unit with flange face connection; the waste heat outlet flange is connected to the waste heat gas inlet flange; the first multi-channel integrated flange is connected to the second multi-channel integrated flange.

[0013] Optionally, the three independent flow channels provided in the first multi-channel integrated flange are a first air inlet, a first air outlet, and a second air inlet; the three independent flow channels provided in the second multi-channel integrated flange are a second heat exchanger outlet, a third heat exchanger inlet, and a third heat exchanger outlet.

[0014] The first multi-channel integrated flange is connected to the second multi-channel integrated flange, so that the first air inlet is connected to the outlet of the second heat exchanger, the first air outlet is connected to the inlet of the third heat exchanger, and the second air inlet is connected to the outlet of the third heat exchanger.

[0015] Optionally, it also includes a compensator disposed on the gas-side connection pipeline between the first heat exchanger and the second heat exchanger.

[0016] Optionally, the waste heat gas outlet flange and the first multi-channel integrated flange are disposed on the same plane of the outer wall of the pressure-bearing shell.

[0017] Optionally, the outer wall of the pressure-bearing shell includes a first end face and a first side face that are perpendicular to each other; the waste heat gas outlet flange is disposed on the first end face, and the first multi-channel integrated flange is disposed on the first side face.

[0018] Optionally, the outer wall of the pressure-bearing shell is provided with a plurality of waste heat gas outlet flanges and a corresponding number of the first multi-channel integrated flanges; the integrated heat exchanger unit is in multiple sets and is provided on the outer wall of the pressure-bearing shell.

[0019] Optionally, the multiple sets of integrated heat exchanger units may be arranged in one or a combination of the following ways: (a) arranged circumferentially along the outer wall of the pressure-bearing shell, wherein the circumferential arrangement includes arranging along all or part of the circumferential arc segments; (b) arranged in an array on the same side of the outer wall of the pressure-bearing shell; (c) arranged in multiple different lateral orientations on the outer wall of the pressure-bearing shell.

[0020] Optionally, the first heat exchanger is a gas-to-gas heat exchanger, and the integrated cooling unit is a gas-to-liquid heat exchange unit; the high-temperature waste heat gas generated in the closed Brayton cycle power equipment flows sequentially through the gas-to-gas heat exchanger and the gas-to-liquid heat exchange unit to be cooled.

[0021] Optionally, the first heat exchanger, the second heat exchanger, and the third heat exchanger are each independently selected from one of a tubular heat exchanger, a plate heat exchanger, a plate-fin heat exchanger, or a printed circuit board heat exchanger.

[0022] Optionally, the integrated heat exchanger unit is made of a metallic material, including stainless steel, aluminum alloy, copper alloy, and titanium alloy.

[0023] As described above, this invention provides an integrated heat exchange module for closed-loop Brayton cycles, comprising a pressure-bearing shell and an integrated heat exchanger unit. The pressure-bearing shell has multiple sets of first working fluid flange interfaces, including a waste heat gas outlet flange and a first multi-channel integrated flange. The integrated heat exchanger unit includes first, second, and third heat exchangers, with the second and third heat exchangers forming an integral cooling structure. The integrated heat exchanger unit is equipped with a waste heat gas inlet flange and a second multi-channel integrated flange for collecting the gas-side inlet and outlet. The two sets of flange interfaces are directly connected and fastened to achieve a sealed connection of the working fluid flow path, replacing traditional decentralized piping. This module has a compact structure, reduces the number of pipes, and significantly saves space; it also eliminates local resistance in bends, improving system efficiency; and it is easy to assemble and disassemble, supporting rapid modular assembly and maintenance. This invention provides an efficient and compact integrated solution for heat-work conversion in advanced nuclear energy and space propulsion systems. Attached Figure Description

[0024] Figure 1 The diagram shown is a structural schematic of an integrated heat exchange module for a closed-loop Brayton cycle according to an embodiment of the present invention.

[0025] Figure 2 The diagram shown is a structural schematic of the integrated heat exchanger unit according to an embodiment of the present invention.

[0026] Figure 3 The diagram shown is a structural schematic of the first heat exchanger according to an embodiment of the present invention.

[0027] Figure 4 The diagram shown is a structural schematic of an integral cooling unit according to an embodiment of the present invention.

[0028] Figure 5 The diagram shown is a top view of the bottom of an integral cooling unit according to an embodiment of the present invention.

[0029] Explanation of reference numerals in the attached figures

[0030] 100 Pressure shell 110 First end face 120 First side view 200 Integrated heat exchanger unit 210 First heat exchanger 220 Second heat exchanger 230 Third heat exchanger 240 compensator 250 Integrated cooling unit 310 High-pressure cooling medium inlet 320 High-pressure cooling medium outlet 330 First cooling medium inlet 340 First cooling medium outlet 410 Waste heat gas outlet flange 420 First heat exchanger outlet 430 First multi-channel integrated flange 431 First air intake 432 First air outlet 433 Second air intake 440 Waste heat gas inlet flange 450 Second multi-channel integrated flange 451 Second heat exchanger outlet 452 Third heat exchanger inlet 453 Third heat exchanger outlet Detailed Implementation

[0031] The following specific examples illustrate the implementation of the present invention. 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.

[0032] It should be noted that the illustrations provided in this embodiment 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.

[0033] Example

[0034] This embodiment provides an integrated heat exchange module for a closed-loop Brayton cycle. The following will refer to the appendix to the instruction manual. Figure 1 ~Appendix Figure 5 This document introduces and explains the integrated heat exchange module for closed-loop Brayton cycles. The integrated heat exchange module for closed-loop Brayton cycles includes: a pressure-bearing shell 100, a first working fluid flange interface group, at least one integrated heat exchanger unit 200, and a second working fluid flange interface group.

[0035] See Figure 1 The pressure-bearing shell 100 is used to form the pressure-bearing structure of the closed Brayton cycle power equipment; the first working fluid flange interface group is provided on the outer wall of the pressure-bearing shell 100, and the first working fluid flange interface group includes a waste heat gas outlet flange 410 and a first multi-channel integrated flange 430.

[0036] Specifically, the pressure-bearing shell 100 serves as the pressure-bearing structure of the closed-loop Brayton cycle power unit, integrating the core high-temperature and high-pressure components of the power plant. In a preferred embodiment of the invention, the pressure-bearing shell 100 integrates core rotating machinery such as a turbine and compressor arranged coaxially. The first working fluid flange interface group is precisely designed and arranged according to the requirements of the internal working fluid flow channel, to achieve efficient and compact integration of the power unit with the subsequent heat exchange module. In this embodiment, the first working fluid flange interface group is formed on the outer wall of the pressure-bearing shell 100. In other embodiments, the first working fluid flange group is fixed to the outer wall of the pressure-bearing shell 100 by fastening bolts to ultimately form a compact unit.

[0037] Furthermore, the waste heat gas outlet flange 410 is used to draw out high-temperature waste heat gas (such as helium or supercritical carbon dioxide waste heat gas used for turbine work) from the closed Brayton cycle power plant, thereby guiding it to the subsequent heat exchange module to provide a gas source for subsequent waste heat gas recovery or multi-stage cooling. In this embodiment, the interface position, size, and direction of the high-temperature waste heat gas must match the flow channel inside the pressure shell 100 to minimize flow disturbance and pressure loss caused by the extraction process. The first multi-channel integrated flange 430 integrates multiple independent and isolated flow channels to achieve synchronous exchange of various working fluids between the pressure shell 100 and the subsequent heat exchange module.

[0038] See Figures 2-4 The integrated heat exchanger unit 200 includes a first heat exchanger 210, a second heat exchanger 220 and a third heat exchanger 230; the second heat exchanger 220 and the third heat exchanger 230 are connected in series on the circulating cooling medium side to form an integral cooling unit 250; the outlet of the first heat exchanger 210 is connected to the inlet of the second heat exchanger 220.

[0039] The second working fluid flange interface group is located in the integrated heat exchanger unit 200 and is correspondingly set with the first working fluid flange interface group. The second working fluid flange interface group includes a waste heat gas inlet flange 440 and a second multi-channel integrated flange 450. The waste heat gas inlet flange 440 is set at the inlet of the first heat exchanger 210, and the second multi-channel integrated flange 450 is set on the gas side of the integrated cooling unit 250 to serve as the docking interface for the gas side inlet and outlet of the integrated cooling unit 250.

[0040] The flanges in the first working fluid flange interface group and the corresponding flanges in the second working fluid flange interface group are directly attached and fastened through the flange sealing surfaces, thereby directly connecting the structure between the pressure shell 100 and the integrated heat exchanger unit 200, and integrating them into a compact unit with flange face connection; the waste heat outlet flange 410 is connected to the waste heat gas inlet flange 440; the first multi-channel integrated flange 430 is connected to the second multi-channel integrated flange 450.

[0041] Specifically, the integrated heat exchanger unit 200, as a pre-integrated independent functional module, organically integrates the working fluid side and cooling medium side flow paths of the first heat exchanger 210, the second heat exchanger 220, and the third heat exchanger 230 through flow channel design and structural arrangement, forming a compact multi-stage heat exchange system. The second heat exchanger 220 and the third heat exchanger 230 share a single cooling medium supply and return pipeline (unmarked), saving space for separate cooling medium supply piping systems and installation arrangements, while also reducing the number of cooling medium piping flanges and installation space for the two heat exchangers. This simplifies system connections and improves the energy efficiency of the integrated cooling unit 250 through the recycling of the cooling medium. The first heat exchanger 210 has a first heat exchanger outlet 420 connected to the inlet of the second heat exchanger 220, allowing the high-temperature waste heat gas to enter the subsequent cooling stage after leaving the first heat exchanger 210, achieving process continuity and minimizing resistance.

[0042] For further details, please refer to [link / reference]. Figure 1The second working fluid flange interface group is used for reliable docking with the pressure shell 100. The waste heat gas inlet flange 440 is located at the inlet of the first heat exchanger 210, ensuring a compact and reliable high-temperature waste heat gas introduction path. The second multi-channel integrated flange 450 gathers and leads multiple gas-side process interfaces involved in the integrated cooling unit 250, such as the inlet and outlet of different levels of cooling gases and the return port of the final cooled gas, through internal flow channels to the same flange sealing surface. In this embodiment, the pressure shell 400 uses pre-reserved flange mounting holes at each gas inlet and outlet position, avoiding structural designs such as bends and volutes that increase space requirements. The second working fluid flange interface group can be formed on the integrated heat exchange unit 200; in another embodiment, the second working fluid flange interface group can be installed on the integrated heat exchange unit 200 using bolt fasteners.

[0043] By adopting an integrated design, the first heat exchanger 210, the second heat exchanger 220, and the third heat exchanger 230 are integrated into an integrated heat exchanger unit. This allows the exchange of working fluid, which previously required multiple independent interfaces and complex external manifolds, to be completed in one go through a single flange connection. This avoids multiple bends and connecting flanges in the fluid flow direction, greatly simplifying the system connection structure, reducing the overall dimensions, saving installation space, achieving a compact overall design, and improving module encapsulation and on-site assembly efficiency. This makes the entire integrated heat exchanger unit 200 a modular component with complete functionality, standardized interfaces, and support for overall disassembly and assembly. More importantly, this connection method provides the working fluid gas with a short, straight, and streamlined internal flow path. The gas directly enters the internal flow path of the integrated heat exchanger unit 200 through the connection surface, avoiding the energy loss caused by repeatedly changing the flow direction and velocity in traditional methods, improving the flow efficiency of the thermodynamic cycle, and contributing to the overall performance improvement of the system.

[0044] As an example, see Figure 1 The first multi-channel integrated flange 430 has three independent flow channels, namely the first air inlet 431, the first air outlet 432, and the second air inlet 433; see reference. Figure 5 The second multi-channel integrated flange 450 has three independent flow channels, namely the second heat exchanger outlet 451, the third heat exchanger inlet 452, and the third heat exchanger outlet 453; wherein, the waste heat gas outlet flange 410 is connected to the waste heat gas inlet flange 440; the first multi-channel integrated flange 430 is connected to the second multi-channel integrated flange 450, so that the first air inlet 431 is connected to the second heat exchanger outlet 451, the first air outlet 432 is connected to the third heat exchanger inlet 452, and the second air inlet 433 is connected to the third heat exchanger outlet 453.

[0045] Specifically, the first multi-channel integrated flange 430 and the second multi-channel integrated flange 450 are integral flanges. High-temperature waste heat gas enters the first heat exchanger 210 from the waste heat gas outlet flange 410 through the waste heat gas inlet flange 440, and is then cooled by the cooling medium flow path within the first heat exchanger 210. The second heat exchanger 220 and the third heat exchanger 230 are connected in series on the circulating cooling medium side, forming an integral cooling unit 250. The second heat exchanger 220 and the third heat exchanger 230 are internally separated and sealed, forming their own high-temperature waste heat gas channels. In addition to corresponding to the second heat exchanger outlet 451, the third heat exchanger inlet 452, and the third heat exchanger outlet 453 in the installation area of ​​the integrated heat exchanger unit 200. A solid installation protection area is also provided next to the second heat exchanger outlet 451. This increases the contact area between the second multi-channel integrated flange 450 and the first multi-channel integrated flange 430 during the fitting process, helping to form a more uniform and stable tightening force during bolt tightening and preventing leakage or flange surface deformation caused by uneven pressure. Simultaneously, it absorbs and disperses bolt tightening force, effectively preventing deformation of the edge (sealing surface) of the adjacent second heat exchanger outlet through-hole 220, ensuring reliable sealing. This improves the local structural strength of the flange body, making the overall installation more stable and reducing vibration or fretting during operation.

[0046] In this embodiment, the high-temperature waste heat gas is helium. The first heat exchanger 210 is provided with a high-pressure cooling medium inlet 310 and a high-pressure cooling medium outlet 320 to form a first cooling flow path. The high-temperature waste heat gas undergoes first-stage cooling after passing through the first cooling flow path of the first heat exchanger 210. Then, the high-temperature waste heat gas undergoes second-stage cooling through the second heat exchanger 220. The integral cooling unit 250 is provided with independent flow channels. The high-temperature waste heat gas that has undergone second-stage cooling flows into the pressure-bearing shell 100 through "second heat exchanger outlet 451 → first inlet 431" for first-stage treatment (e.g., compression by a compressor). Then, it enters the third heat exchanger 230 through "first outlet 432 → third heat exchanger inlet 452" inside the pressure-bearing shell 100 for third-stage cooling. Then, it enters the pressure-bearing shell 100 through "third heat exchanger outlet 453 → second outlet 433" for second-stage treatment (e.g., further compression by a compressor), thereby the pressure-bearing shell 100 outputs high-pressure cooling medium. In this embodiment, high-pressure cooling helium gas enters the first heat exchanger 210 as a high-pressure cooling medium. After cooling, the high-pressure cooling medium flows out through the high-pressure cooling medium outlet 320 connected to the first heat exchanger 210 to the heating source. In this embodiment, the high-pressure cooling helium gas flows into the reactor core to continue acquiring heat and eventually returns to the turbine (power equipment) inside the pressure vessel 100 to perform work. Of course, in other embodiments, the high-pressure cooling medium can also be other suitable working fluids such as supercritical CO2 to form an independent closed-loop power cycle. From the core process of the thermodynamic cycle, different working fluid systems are similar in the "waste heat recovery-reuse" stage. The high-temperature waste heat gas discharged from the turbine all flows through the first heat exchanger 210 (regenerator). In the first heat exchanger 210, the waste heat it carries is transferred to the high-pressure cooling medium from the compressor outlet inside the pressure vessel 100, thus preheating the high-pressure cooling medium. This reheating process is a common key to improving the energy conversion efficiency of the Brayton cycle.

[0047] In this embodiment, the inlet of the first heat exchanger is equipped with a waste heat gas inlet flange, and the outlet of the first heat exchanger is directly connected to the inlet of the second heat exchanger, effectively reducing the number of flanges by half compared to the four interfaces of a traditional heat exchanger. In a preferred embodiment, to increase the compactness of the first heat exchanger, the pipeline containing the high-temperature waste heat gas uses 316 stainless steel pipe with an outer diameter of 1.5 mm and a wall thickness of 0.1 mm. The number of stainless steel heat exchange tubes in a single first heat exchanger reaches more than 40,000, and the heat exchange area reaches 125 m². 2 Its volume is 0.24m³. 3The first heat exchanger is a standard 12mm outer diameter, 0.2mm wall thickness stainless steel tube heat exchanger, approximately one-third the volume of the standard unit, significantly improving compactness. Similarly, for the second and third heat exchangers, by designing them as an integral cooling unit, each heat exchanger eliminates one inlet / outlet flange for the circulating cooling water. The inlet of the second heat exchanger is connected to the outlet of the first heat exchanger via corresponding flanges. In the integral cooling unit, since the cooling water piping is shared, the cooling water piping uses 4mm outer diameter, 0.3mm wall thickness 316L stainless steel tubes. The second heat exchanger has 5700 heat exchange tubes and a heat exchange area of ​​6.6m². 2 Volume 0.04m³ 3 The third heat exchanger has 5700 heat exchange tubes and a heat exchange area of ​​7.2m². 2 Volume 0.15m³ 3 .

[0048] As an example, a compensator 240 is also included, which is disposed on the gas-side connection line between the first heat exchanger 210 and the second heat exchanger 220.

[0049] For details, please refer to Figures 1-2 The compensator 240 is mainly used to absorb thermal displacement caused by temperature changes in the piping system, as well as vibrations generated during equipment operation. This design effectively eliminates additional stress acting on the interfaces and gas pipelines of the integrated heat exchanger unit 200, preventing fatigue leakage caused by stress concentration, thereby improving the reliability and safety of the entire heat exchange system during long-term operation. In one specific embodiment, the compensator 240 includes an axial metal bellows compensator, but it is not limited to this.

[0050] As an example, the waste heat gas outlet flange 410 and the first multi-channel integrated flange 430 are located on the same plane on the outer wall of the pressure housing 100.

[0051] Specifically, as an example, the waste heat gas outlet flange 410 and the first multi-channel integrated flange 430 adopt a coplanar design, both located on the same plane of the outer wall of the pressure-bearing shell 100. This design provides a unified interface for integrated layout and modular installation, greatly improving assembly efficiency and accuracy. On the other hand, the flat outer wall of the pressure-bearing shell 100 reduces the complexity of the forming and welding process, enhances the overall pressure uniformity and structural strength of the pressure-bearing shell 100, and is conducive to achieving a compact and highly reliable equipment design.

[0052] As an example, see Figures 1-2 The outer wall of the pressure-bearing housing 100 includes a first end face 110 and a first side face 120 that are perpendicular to each other; the waste heat gas outlet flange 410 is disposed on the first end face 110, and the first multi-channel integrated flange 430 is disposed on the first side face 120.

[0053] Specifically, the waste heat gas outlet flange 410, which is subjected to the impact of high-temperature airflow, is arranged on the first end face 110, which has a stronger structural rigidity, while other interfaces are located on the first side face 120. This layout utilizes the high rigidity of the end face to disperse the main mechanical stress and uses spatial isolation to reduce the impact of high-temperature radiation on other interfaces. On the other hand, the mutually perpendicular flange positions provide independent thermal expansion directions for the different pipelines connected thereto, which can effectively absorb thermal displacement. This significantly reduces the risk of stress coupling caused by inconsistent thermal expansion directions, i.e., the possibility of destructive additional stress generated inside the pressure-bearing structure due to the incoordination and mutual constraint of deformation (such as thermal expansion) between the components of the pressure-bearing shell 100. This improves the safety of the system under thermal cycling conditions.

[0054] As an example, the outer wall of the pressure shell 100 is provided with multiple waste heat gas outlet flanges 410 and a corresponding number of first multi-channel integrated flanges 430; the integrated heat exchanger units 200 are in multiple groups and are provided on the outer wall of the pressure shell 100.

[0055] For details, please refer to Figure 1 The diagram illustrates four sets of first working fluid interface flanges on the pressure shell 100. Only one integrated heat exchanger unit 200 is shown here; however, multiple integrated heat exchanger units 200 can be configured, evenly distributed on the outer wall of the pressure shell 100. This layout helps to divert the concentrated high-temperature waste heat gas flow at the outlet of the pressure shell 100, distributing it evenly to each parallel integrated heat exchanger unit 200. This avoids excessive heat load at a single point, optimizes the uniformity of the flow and temperature fields inside and outside the pressure shell 100, and positively impacts overall heat exchange efficiency, reduces local thermal stress, and extends equipment life. Simultaneously, each integrated heat exchanger unit 200 has an independent medium circulation and control system, which not only improves the overall heat recovery efficiency of the system but also provides operational redundancy. Even if one heat exchanger unit needs to be shut down for maintenance or malfunctions, the others can still operate normally, ensuring the system does not completely fail and greatly improving the system's reliability and continuous operation capability. Of course, the number of the first working medium interface flange group on the outer wall of the pressure shell 100 is not limited to 1, 2, 3, or 4, and the number of groups can be set according to actual needs.

[0056] As an example, the multiple integrated heat exchanger units 200 may be arranged in one or a combination of the following ways: (a) arranged circumferentially along the outer wall of the pressure housing 100, wherein the circumferential arrangement includes arranging along all or part of the circumferential arc segment; (b) arranged in an array on the same side of the outer wall of the pressure housing 100; or (c) arranged in multiple different lateral orientations on the outer wall of the pressure housing 100.

[0057] For details, please refer to Figure 1In this embodiment, theoretical calculations are performed on the second heat exchanger 220 and the third heat exchanger 230 of the gas-liquid working fluid heat exchanger according to the thermal parameter requirements of the system. The same method is used to perform theoretical design calculations on the first heat exchanger 210 (gas-gas working fluid heat exchanger). After analyzing the structure of the three heat exchangers, and considering the limited space and the size of the gas turbine shell, the three heat exchangers are arranged in a ring structure on the shell. The integrated heat exchanger unit 200 is arranged uniformly or symmetrically along the outer wall of the pressure-bearing shell 100, which is beneficial for uniformly distributing the high-temperature gas flow, ensuring consistent load on each heat exchange unit, and ensuring uniform heating of the pressure-bearing shell as a whole, reducing local thermal stress and extending the life of the pressure-bearing equipment. This arrangement is suitable for situations requiring radial uniform distribution and cooling of the outflowing high-temperature waste heat gas, and can optimize the heat distribution of the shell. This circumferential arrangement can be flexibly adjusted according to the actual gas flow rate. A full circumference can be used to achieve maximum distribution capacity, or only along a portion of the circumferential arc (such as a 180° or 120° range) to adapt to asymmetrical external spaces. In this embodiment, the pressure vessel 100 exhibits a 180° arc segment, but it can also be any arc segment such as 45°, 60°, 90°, 135°, 225°, 270°, or 360°. Multiple integrated heat exchanger units are arranged in a ring within the vessel, better fitting the space and making full use of it. Through the optimized combination of heat exchangers, the volume is reduced, correspondingly increasing the compactness, providing the necessary conditions for the miniaturization and mobility of the reactor. As a preferred embodiment, six integrated heat exchanger units are arranged in a ring around the pressure vessel, with each unit contributing up to 1 / 6 of the total heat exchange power. This ring-integrated layout fundamentally changes the traditional loose, split structure, maximizing space utilization while ensuring the high efficiency and reliability of the heat-work conversion process.

[0058] Furthermore, the layout of the integrated heat exchanger unit 200 arranged in a compact longitudinal and transverse array on the same side (such as the top or side) of the outer wall of the pressure shell 100, with a dense array (such as 2×2 or 3×3) on the same side of the outer wall of the pressure shell 100, greatly saves the radial space of the equipment at the installation site, achieves a high degree of interface integration, and facilitates management and maintenance in space-constrained areas.

[0059] Furthermore, the integrated heat exchanger unit 200 is arranged in multiple different lateral orientations on the outer wall of the pressure shell 100 (such as opposite sides or three adjacent sides), avoiding excessive pipeline density on a single side, facilitating arrangement in complex spaces, and providing independent access points for different heat recovery flow paths. The above layout can be used individually or combined according to ultra-large processing capacity or special site shapes (e.g., dual-sided array plus partial circumferential arrangement), demonstrating the system's high flexibility in engineering adaptation.

[0060] As an example, the first heat exchanger 210 is a gas-to-gas heat exchanger, and the integral cooling unit is a gas-to-liquid heat exchange unit; the high-temperature waste heat gas generated in the closed Brayton cycle power equipment flows through the gas-to-gas heat exchanger and the gas-to-liquid heat exchange unit in sequence and is cooled.

[0061] Specifically, in this embodiment, the first heat exchanger 210 is a gas-to-gas heat exchanger, mainly used to recover the high-temperature waste heat gas generated by the power equipment inside the pressure shell 100; the cooling medium flow path formed by the high-pressure cooling medium inlet 310 and the high-pressure cooling medium outlet 320 originates from the high-pressure cooling medium after compression inside the pressure shell 100, thereby achieving gas-to-gas heat exchange. The integrated cooling unit is a high-efficiency gas-to-liquid heat exchange unit, used to complete the final cooling. In the process flow of a specific embodiment, the high-temperature waste heat gas first enters the first heat exchanger 210 for gas-to-gas heat exchange, transferring part of its heat energy to the high-pressure cooling medium, realizing the reuse of heat energy; the circulating cooling medium is cooling water. In this embodiment, refer to... Figure 4 The integrated cooling unit is equipped with a first cooling medium inlet 330 and a first cooling medium outlet 340. Cooling water enters the integrated cooling unit through the first cooling medium inlet 330 and flows along a serpentine or tortuous flow channel inside the integrated cooling unit to enhance heat exchange efficiency. It then flows out through the first cooling medium outlet 340 and returns to the external circulating cooling system. The initially cooled gas (e.g., helium) then enters the gas-liquid heat exchange unit for further cooling before proceeding to the next process. This composite process design not only saves primary energy consumption through heat recovery but also optimizes the operating temperature difference of each heat exchange unit through staged cooling, reducing irreversible losses. Ultimately, it maximizes system energy efficiency and economic benefits while ensuring cooling effectiveness. The above embodiment uses helium as the working fluid and a nuclear reactor as the heat source to specifically demonstrate the application of the present invention. However, the scope of protection of the present invention is not limited to this specific combination. By using a multi-channel integrated flange, the pressure-bearing housing 100 is directly and sealedly connected to an integrated heat exchanger unit 200 containing at least one gas-to-gas heat exchanger unit and one gas-to-liquid heat exchanger unit, so as to achieve staged cooling of waste heat gas and efficient recovery of heat energy. Regardless of the specific working fluid or heat source used, it should be considered to fall within the protection scope of this invention.

[0062] As an example, the first heat exchanger 210, the second heat exchanger 220 and the third heat exchanger 230 are each independently selected from one of a tubular heat exchanger, a plate heat exchanger, a plate-fin heat exchanger or a printed circuit board heat exchanger.

[0063] Specifically, the first heat exchanger 210, the second heat exchanger 220, and the third heat exchanger 230 can be independently selected from one of the following types of heat exchangers—tube heat exchanger, plate heat exchanger, plate-fin heat exchanger, or printed circuit board heat exchanger—based on the working pressure, temperature, and compactness requirements of their respective circuits. For example, for heat exchange circuits that bear the highest pressure and temperature (such as the first heat exchanger 210), a tube heat exchanger with strong pressure resistance can be selected; for internal regeneration or cooling circuits that require extremely high compactness and heat exchange efficiency (such as the second heat exchanger 220 and the third heat exchanger 230), plate-fin heat exchangers or printed circuit board heat exchangers can be preferentially selected to maximize the heat exchange area within a limited space.

[0064] As an example, the integrated heat exchanger unit 200 is made of a metallic or ceramic material, including stainless steel, aluminum alloy, copper alloy, titanium alloy, nickel-based superalloy, and cobalt-based superalloy; the ceramic material includes silicon carbide ceramic.

[0065] Specifically, the material selection for the integrated heat exchanger unit 200 needs to be tailored to the specific circumstances. For example, stainless steel can meet the needs of general applications requiring good overall performance and corrosion resistance; aluminum alloys offer advantages such as light weight, good thermal conductivity, low cost, and dry, inert gas environments; copper alloys are suitable for applications with high thermal conductivity requirements; and titanium alloys are suitable for extreme corrosive environments requiring high corrosion resistance and strength. Nickel-based and cobalt-based superalloys possess excellent high-temperature strength, creep resistance, and oxidation resistance, enabling them to withstand extreme thermal stress conditions. Through targeted material selection, overall performance and cost can be optimized while ensuring reliability and safety.

[0066] In summary, this invention provides an integrated heat exchange module for closed-loop Brayton cycles, comprising a pressure-bearing shell and an integrated heat exchanger unit. The pressure-bearing shell has multiple sets of first working fluid flange interfaces, including a waste heat gas outlet flange and a first multi-channel integrated flange. The integrated heat exchanger unit includes first, second, and third heat exchangers, with the second and third heat exchangers forming an integral cooling structure. The integrated heat exchanger unit is equipped with a waste heat gas inlet flange and a second multi-channel integrated flange for collecting gas-side inlets and outlets. The two sets of flange interfaces are directly connected and fastened, achieving a sealed connection of the working fluid flow path, replacing traditional distributed piping. This module has a compact structure, reducing the number of pipes in the fluid flow direction, shrinking the overall dimensions, and significantly saving space; it also eliminates local resistance in bends, improving system efficiency; and it is easy to assemble and disassemble, supporting rapid modular assembly and maintenance. This invention provides an efficient and compact integrated solution for heat-work conversion in advanced nuclear energy and space propulsion systems. Therefore, this invention effectively overcomes the various shortcomings of existing technologies and has high industrial application value.

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

Claims

1. An integrated heat exchange module for a closed-loop Brayton cycle, characterized in that, include: Pressure-bearing housing, which is used to form the pressure-bearing structure of a closed Brayton cycle power plant; The first working fluid flange interface group is disposed on the outer wall of the pressure-bearing shell, and the first working fluid flange interface group includes a waste heat gas outlet flange and a first multi-channel integrated flange. At least one set of integrated heat exchanger units, the integrated heat exchanger unit including a first heat exchanger, a second heat exchanger and a third heat exchanger; the second heat exchanger and the third heat exchanger are connected in series on the circulating cooling medium side to form an integral cooling unit; the outlet of the first heat exchanger is connected to the inlet of the second heat exchanger; The second working fluid flange interface group is located on the integrated heat exchanger unit and is correspondingly arranged with the first working fluid flange interface group. The second working fluid flange interface group includes a waste heat gas inlet flange and a second multi-channel integrated flange. The waste heat gas inlet flange is arranged at the inlet of the first heat exchanger, and the second multi-channel integrated flange is arranged on the gas side of the integrated cooling unit to serve as the docking interface for the gas side inlet and outlet of the integrated cooling unit. The first working fluid flange interface group and the corresponding flanges in the second working fluid flange interface group are directly attached and fastened through the flange sealing surface, thereby directly connecting the structure between the pressure shell and the integrated heat exchanger unit and integrating them into a compact unit with flange face connection; the waste heat gas outlet flange is connected to the waste heat gas inlet flange; the first multi-channel integrated flange is connected to the second multi-channel integrated flange.

2. The integrated heat exchange module for closed-loop Brayton cycle as described in claim 1, characterized in that: The first multi-channel integrated flange has three independent flow channels, namely a first air inlet, a first air outlet, and a second air inlet; the second multi-channel integrated flange has three independent flow channels, namely a second heat exchanger outlet, a third heat exchanger inlet, and a third heat exchanger outlet. The first multi-channel integrated flange is connected to the second multi-channel integrated flange, so that the first air inlet is connected to the outlet of the second heat exchanger, the first air outlet is connected to the inlet of the third heat exchanger, and the second air inlet is connected to the outlet of the third heat exchanger.

3. The integrated heat exchange module for closed-loop Brayton cycle as described in claim 1, characterized in that: It also includes a compensator, which is disposed on the gas-side connection pipeline between the first heat exchanger and the second heat exchanger.

4. The integrated heat exchange module for closed-loop Brayton cycle according to claim 1, characterized in that: The waste heat gas outlet flange and the first multi-channel integrated flange are located on the same plane on the outer wall of the pressure-bearing shell.

5. The integrated heat exchange module for closed-loop Brayton cycle according to claim 1, characterized in that: The outer wall of the pressure-bearing shell includes a first end face and a first side face that are perpendicular to each other; the waste heat gas outlet flange is disposed on the first end face, and the first multi-channel integrated flange is disposed on the first side face.

6. The integrated heat exchange module for closed-loop Brayton cycle according to claim 4 or 5, characterized in that: The outer wall of the pressure-bearing shell is provided with a plurality of waste heat gas outlet flanges and a corresponding number of the first multi-channel integrated flanges; the integrated heat exchanger unit is in multiple sets and is provided on the outer wall of the pressure-bearing shell.

7. The integrated heat exchange module for closed-loop Brayton cycle according to claim 6, characterized in that: The arrangement of multiple sets of integrated heat exchanger units is one or a combination of the following: (a) arranged circumferentially along the outer wall of the pressure-bearing shell, wherein the circumferential arrangement includes arranging along all or part of the circumferential arc segment; (b) arranged in an array on the same side of the outer wall of the pressure-bearing shell; (c) arranged in multiple different lateral orientations on the outer wall of the pressure-bearing shell.

8. The integrated heat exchange module for closed-loop Brayton cycle according to claim 1, characterized in that: The first heat exchanger is a gas-to-gas heat exchanger, and the integrated cooling unit is a gas-to-liquid heat exchange unit; the high-temperature waste heat gas generated in the closed Brayton cycle power equipment flows sequentially through the gas-to-gas heat exchanger and the gas-to-liquid heat exchange unit and is cooled.

9. The integrated heat exchange module for closed-loop Brayton cycle according to claim 1, characterized in that: The first heat exchanger, the second heat exchanger, and the third heat exchanger are each independently selected from one of the following: a tubular heat exchanger, a plate heat exchanger, a plate-fin heat exchanger, or a printed circuit board heat exchanger.

10. The integrated heat exchange module for closed-loop Brayton cycle according to claim 1, characterized in that: The integrated heat exchanger unit is made of metallic or ceramic materials; the metallic materials include one of stainless steel, aluminum alloy, copper alloy, titanium alloy, nickel-based high-temperature alloy, and cobalt-based high-temperature alloy; the ceramic materials include silicon carbide ceramics.

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