Two-phase flow heat exchange structure, evaporator, condenser and two-phase flow heat exchange system

Abstract

The invention relates to the technical field of heat dissipation equipment, and discloses a two-phase flow heat exchange structure, an evaporator, a condenser and a two-phase flow heat exchange system.The two-phase flow heat exchange structure comprises an evaporation runner and a rotational flow runner which are connected; the evaporation flow channel is provided with a necking structure for promoting gas-liquid conversion; the rotational flow channel is provided with a bending structure used for separating gas and liquid. The evaporator comprises the two-phase flow heat exchange structure. The condenser comprises the two-phase flow heat exchange structure. The two-phase flow heat exchange system comprises the evaporator and the condenser. By means of the two-phase flow heat exchange structure, the heat dissipation capacity of the two-phase flow heat exchange system is improved, it is guaranteed that the driving device can operate safely for a long time, and the requirement for heat dissipation in the extreme environment is met. And miniaturization and light weight of the two-phase flow heat exchange system can be further achieved, so that the two-phase flow heat exchange system is applied to small equipment such as small aircrafts, and the application scene and the application range of the two-phase flow heat exchange system are greatly widened.

Description

Technical Field

[0001] The present invention relates to the technical field of heat dissipation equipment, and in particular to a two-phase flow heat exchange structure, an evaporator, a condenser and a two-phase flow heat exchange system. Background Art

[0002] With the development of electronic equipment integration and the continuous improvement of usage requirements, the heat dissipation of electronic equipment faces the challenges of complex heat source structure and high heat flux density, which makes its heat dissipation problem increasingly prominent. At present, due to the high chip integration of equipment integration and SIP\SOP technology, the local heat flux density can reach tens to hundreds of watts per square centimeter, which restricts the development of electronic heat dissipation technology. It is necessary to find more efficient heat dissipation technology to meet future challenges. The two-phase flow cooling system uses the gas-liquid phase change conversion of liquid working fluid for heat transfer, has a high heat exchange efficiency, and its heat dissipation capacity can reach hundreds of watts per square centimeter. It has a good application prospect in future airborne electronic equipment.

[0003] The existing two-phase flow heat dissipation device has the following problems: it essentially plays a role of temperature equalization, cannot substantially improve the heat dissipation capacity of the system or device, and has a limited scope of application. Summary of the invention

[0004] The technical problem to be solved by the present invention is that the existing two-phase flow heat dissipation device plays a role in temperature uniformity, and the purpose is to provide a two-phase flow heat exchange structure, evaporator, condenser and two-phase flow heat exchange system to solve the above-mentioned problem.

[0005] The present invention is achieved through the following technical solutions: In a first aspect, the present invention provides a two-phase flow heat exchange structure, comprising an evaporation flow channel and a swirl flow channel connected; The evaporation channel has a constriction structure for promoting gas-liquid conversion; The cyclone flow channel has a bending structure for separating gas and liquid.

[0006] In a possible design, the evaporation flow channel includes an inlet area, an evaporation tube and an outlet area. The inlet area and the outlet area are arranged opposite to each other. The evaporation tube is provided with at least one and is used to connect the inlet area and the outlet area. The shrinkage structure is provided at one end of the evaporation tube adjacent to the inlet area.

[0007] In a possible design, the cross-sectional area of ​​the evaporation tube is S1, the cross-sectional area of ​​the necking structure is S2, and S1 ≥ 2S2.

[0008] In a possible design, the swirl flow channel includes a plurality of arc-shaped flow channels and a plurality of bending structures; Adjacent arc-shaped flow channels are coaxial and spaced apart so that the plurality of arc-shaped flow channels are located on the same plane; Adjacent arc-shaped flow channels are connected by a bending structure so that the adjacent arc-shaped flow channels are connected to form a spiral pipeline with a single flow direction and a bend; Correspondingly, one of the outermost arc-shaped flow channel and the innermost arc-shaped flow channel is used for the inflow of working fluid, and the other is used for the outflow of working fluid, and both the inflow and outflow of working fluid are provided with additional bending structures for changing the flow direction.

[0009] In a possible design, a fan-shaped area is provided on the swirl flow channel, and two ends of the arc-shaped flow channel are respectively located on both sides of the fan-shaped area. Accordingly, a plurality of bending structures are respectively located on both sides of the fan-shaped area and connect adjacent arc-shaped flow channels.

[0010] In a possible design, an etching layer for matching the shrinking structure is provided on the evaporation flow channel, and a sandblasting layer for matching the bending structure is provided on the swirl flow channel; The etched layer is obtained by the following steps: S10: preparing an etching solution: preparing a mixture of ferric chloride and hydrochloric acid; S20 etching: adding corrosion inhibitor, and / or, intermittent etching, the intermittent etching adopts etching for 40s, cleaning for 20s and cycle; S30 micro-arc oxidation treatment: obtain an oxide layer of 10μm-20μm; The sandblasting layer is obtained by the following steps: The S10 equipment uses: corundum powder with a diameter less than 0.3mm, a low-pressure compressed air system with a pressure of 0.2-0.4MPa, and a flexible micro-spray nozzle with an inner diameter of ≤0.5mm; S20 sandblasting: At the curved pipe, every 14cm-16cm is divided into a sandblasting section, and sandblasting is performed section by section, and the flexible micro-nozzle nozzle is parallel to the swirl flow channel, and the sandblasting angle is 5°-10°; pulse sandblasting is used at the bending structure; S30 inspection: surface roughness inspection and flow channel air tightness test; Among them, in S30, the surface roughness of the sandblasting layer needs to reach Ra12.5μm.

[0011] In a second aspect, the present invention provides an evaporator based on the two-phase flow heat exchange structure, comprising a shell, a heater and the two-phase flow heat exchange structure; The shell includes a cover plate, a steam generator and an evaporator cavity which are arranged in sequence from bottom to top. The heater is arranged on the cover plate and is used to heat the steam generator. The two-phase flow heat exchange structure is arranged in the evaporator cavity, and the evaporation flow channel is located between the heater and the swirl flow channel.

[0012] In the third aspect, the present invention provides a condenser based on the two-phase flow heat exchange structure, including the two-phase flow heat exchange structure, wherein the two-phase flow heat exchange structure includes an evaporation flow channel and two parallel swirl flow channels, so that the liquid-to-gas ratio of the gas-liquid mixture flowing out of the condenser is ≥94%.

[0013] In a fourth aspect, the present invention provides a two-phase flow heat exchange system, comprising the evaporator, the condenser, an auxiliary port, a liquid storage tank and a driving device; The evaporator, condenser, auxiliary port, liquid storage tank and drive device are connected in sequence to form a closed heat dissipation circuit. The liquid filling volume of the heat dissipation circuit is not less than 90%. The evaporator is arranged near the heat source and is used to absorb heat. The auxiliary port is used as a liquid filling port and an inspection port.

[0014] In one possible design, the liquid storage tank includes a tank body and an extraction flow channel; The tank body has an upper cavity and a lower cavity opposite to each other, the upper cavity is provided with a deflation valve and an inlet, the lower cavity is provided with an outlet, and correspondingly, the inlet and the outlet are respectively connected with pipelines, and the extraction flow channel is located between the upper cavity and the lower cavity; The outer periphery of the extraction flow channel is provided with spiral downward fins, and the outer peripheral surface of the extraction flow channel is close to the inner peripheral surface of the tank body, so that a one-way flow channel is formed between two adjacent fins, and the one-way flow channel is tangent to the inlet and outlet, so that the working medium flows in and out along the tangential direction; Correspondingly, the upper and lower ends of the extraction flow channel are respectively provided with additional pipelines tangent to the one-way flow channel.

[0015] Compared with the prior art, the present invention has the following advantages and beneficial effects: The two-phase heat exchange structure increases the heat dissipation capacity of the two-phase heat exchange system, ensures that the drive device can operate safely for a long time, and meets the heat dissipation requirements of extreme environments. The two-phase heat exchange system can be miniaturized and lightweight, so that it can be used in aircraft and other equipment, greatly broadening the application scenarios and scope of the two-phase heat exchange system. BRIEF DESCRIPTION OF THE DRAWINGS

[0016] In order to more clearly illustrate the technical solutions of the exemplary embodiments of the present invention, the following briefly introduces the drawings required for use in the embodiments. It should be understood that the following drawings only illustrate certain embodiments of the present invention and should not be regarded as limiting the scope. For those of ordinary skill in the art, other relevant drawings can be obtained based on these drawings without creative work. In the drawings: Figure 1 It is a structural schematic diagram of a two-phase flow heat exchange structure.

[0017] Figure 2 Schematic diagram of the structure of the evaporation channel.

[0018] Figure 3 It is a schematic diagram of the structure of the swirl flow channel.

[0019] Figure 4 It is a structural schematic diagram of a two-phase flow heat exchange system.

[0020] Figure 5 It is a structural schematic diagram of an evaporator based on the two-phase flow heat exchange structure.

[0021] Figure 6 It is a structural schematic diagram of a condenser based on the two-phase flow heat exchange structure.

[0022] Figure 7 It is a structural schematic diagram of the liquid storage tank.

[0023] Figure 8 This is a schematic diagram showing the orientation of the system.

[0024] Fig. 9 Schematic diagram of the spectrum of functional vibration.

[0025] Figure 10-12 These are the temperature variation curves of the two-phase flow heat exchange system in the X, Y and Z directions in a vibration environment.

[0026] Figure 13-16 The temperature variation curves of the existing two-phase flow heat dissipation system in the acceleration environment in the X+ direction, X- direction, Y+ direction and Y- direction respectively.

[0027] Fig.17 Schematic diagram of the fluid distribution inside the liquid storage separator of the existing two-phase flow heat dissipation system in an acceleration environment.

[0028] Figure 18-23 These are temperature variation curves of the two-phase flow heat exchange system in the acceleration environment in the X+ direction, X- direction, Y+ direction, Y- direction, Z+ direction and Z- direction respectively.

[0029] Marks and corresponding parts names in the attached drawings: 10. Evaporation flow channel; 101. Inflow area; 102. Evaporation tube; 103. Outflow area; 104. Narrowing structure; 20. Swirl flow channel; 201. Arc flow channel; 202. Bending structure; 203. Additional bending structure; 204. Fan-shaped area; 30. Evaporator; 31. Shell; 32. Heater; 301. Cover plate; 302. Steam generator; 303. Evaporator cavity; 40. Condenser; 50. Auxiliary port; 60. Liquid storage tank; 61. Tank body; 62. Extraction flow channel; 601. Upper cavity; 602. Lower cavity; 603. Release valve; 604. Inlet; 605. Outlet; 606. Fins; 607. Additional pipeline; 70. Drive device. DETAILED DESCRIPTION

[0030] In order to make the objectives, technical solutions and advantages of the present invention more clearly understood, the present invention is further described in detail below in conjunction with embodiments and drawings. The exemplary embodiments of the present invention and their description are only used to explain the present invention and are not intended to limit the present invention.

[0031] In the following description, a large number of specific details are set forth in order to provide a thorough understanding of the present invention. However, it is apparent to one of ordinary skill in the art that these specific details are not necessarily employed to practice the present invention. In other embodiments, in order to avoid obscuring the present invention, well-known structures, circuits, materials, or methods are not specifically described.

[0032] Throughout the specification, references to "one embodiment," "an embodiment," "an example," or "an example" mean that a particular feature, structure, or characteristic described in conjunction with the embodiment or example is included in at least one embodiment of the present invention. Therefore, the phrases "one embodiment," "an embodiment," "an example," or "an example" appearing in various places throughout the specification do not necessarily all refer to the same embodiment or example. In addition, particular features, structures, or characteristics may be combined in one or more embodiments or examples in any suitable combination and / or sub-combination. In addition, it will be appreciated by those of ordinary skill in the art that the figures provided herein are for illustrative purposes and that the figures are not necessarily drawn to scale. The term "and / or" as used herein includes any and all combinations of one or more of the associated listed items.

[0033] In the description of the present invention, the directions or positional relationships indicated by terms such as “front”, “rear”, “left”, “right”, “up”, “down”, “vertical”, “horizontal”, “high”, “low”, “inside” and “outside” are based on the directions or positional relationships shown in the accompanying drawings and are only for the convenience of describing the present invention and simplifying the description. They do not indicate or imply that the device or element referred to must have a specific direction, be constructed and operated in a specific direction. Therefore, they should not be understood as limiting the scope of protection of the present invention.

[0034] Embodiment 1: This embodiment provides a two-phase flow heat exchange system, which includes an evaporator 30 , a condenser 40 , an auxiliary port 50 , a liquid storage tank 60 and a driving device 70 .

[0035] It is easy to understand that the two-phase heat exchange system also includes a fluid pipeline, through which various components are connected to form a closed heat dissipation circuit, and the fluid pipeline is filled with a working medium for heat dissipation. Further, the fluid pipeline can be any suitable existing pipeline, and the working medium can be any suitable existing heat dissipation working medium.

[0036] When working, the heating element is used as the heat source and the working fluid is used as the heat carrier. The heat of the heating element is absorbed in the evaporation section of the heat dissipation circuit, so that the liquid working fluid is heated and evaporated, and flows into the condenser 40 in the form of gas. Under the cooling effect of the condenser 40, it becomes liquid, and the heat is transferred to the external heat sink through the tube wall of the condenser 40 to achieve heat transfer, thereby reducing the working temperature of the heating element. The liquid working fluid condensed in the condenser 40 flows back to the evaporator 30 through the fluid pipeline under the driving force of the driving device 70, and then absorbs heat, evaporates, and flows in the evaporator 30 again, and continuously transfers the heat in the evaporator 30 to the heat sink at the far end, thereby stably and continuously reducing the temperature of the heating element.

[0037] Compared with the existing two-phase flow heat dissipation system, the two-phase flow heat exchange system uses the driving device 70 as the driving source, thereby providing additional power for the flow of the working fluid in the system, overcoming the resistance of the system, and under the conditions of multi-directional acceleration, vibration, etc., the working fluid can still flow along the designed route, effectively expanding the scope of use of the two-phase flow heat exchange system.

[0038] Optionally, the working fluid may be acetone or ammonia, or different working fluids may be matched according to the power consumption of different heating elements. It is easy to understand that any other suitable working fluid may also be selected.

[0039] It is worth noting that the two-phase heat exchange system has more diverse usage scenarios after adding the drive device 70, but it is still limited to conventional scenarios, including but not limited to vehicle cooling systems under stable acceleration, and conventional gravity environment cooling systems in experimental environments. For special scenarios, such as aircraft at high altitudes and multi-angle acceleration, due to the sensitivity of the two-phase flow to acceleration and vibration, its working efficiency will be greatly reduced, and in extreme cases it may even fail directly, causing the collapse of the cooling system and the direct burning of the heat dissipation components.

[0040] In view of this, a two-phase flow heat exchange structure is proposed here, specifically: like Figure 1-Figure 6 As shown, a two-phase flow heat exchange structure includes an evaporation flow channel 10 and a swirl flow channel 20 connected to each other; The evaporation channel 10 has a constriction structure 104 for promoting gas-liquid conversion; The cyclone flow channel 20 has a bending structure 202 for separating gas and liquid.

[0041] For a two-phase flow heat exchange system, since the working fluid will change state between liquid and gas, if the proportion of the gaseous working fluid is relatively large, that is, the heat dissipation efficiency of the two-phase flow heat exchange system is low, it is inevitable that the gaseous working fluid will flow into the drive device 70. The gaseous working fluid will cause cavitation on the blades of the drive device 70, resulting in damage to the drive device 70, causing the two-phase flow heat exchange system to lose driving force.

[0042] Based on this, for the two-phase flow heat exchange structure, the gas-liquid conversion efficiency is increased by the evaporation channel 10, assisted by the constriction structure 104, that is, when the cross-sectional area of ​​the evaporation channel 10 is suddenly reduced, the fluid flow rate increases sharply. According to Bernoulli's principle, the increase in flow rate will cause the local pressure to decrease. If the temperature of the fluid is close to the saturation temperature at this time, the pressure drop will directly trigger the liquid vaporization (flash effect). At the same time, the sudden change in cross-sectional area will induce turbulence, destroy the thermal boundary layer of the fluid, enhance the heat exchange efficiency between the liquid and the high-temperature wall, and promote the gasification effect of the liquid. At the same time, turbulence can also increase the bubble nucleation rate of the phase change working fluid, thereby accelerating the gas-liquid conversion effect.

[0043] Therefore, for the evaporator 30, after the two-phase flow heat exchange structure is applied, the flash effect and the turbulence caused by the constriction structure 104 are used to increase the heat absorption of the working fluid, effectively improving the upper limit and heat absorption capacity of the two-phase flow heat exchange system, and the heat generated by the heating element is timely absorbed and transferred, so as to achieve the purpose of protecting the heating element. For the condenser 40, after the two-phase flow heat exchange structure is applied, the turbulence is caused by the constriction structure 104, and the heat exchange efficiency between the gas and the low-temperature wall is enhanced. With the help of the heat dissipation components in the condenser 40, such as heat dissipation fins, heat dissipation fans, etc., the heat is dissipated in time, and the working fluid is rapidly liquefied, so as to ensure that the liquid accounts for a large proportion in the gas-liquid mixture flowing out of the condenser 40, thereby protecting the drive device 70.

[0044] The swirl flow channel 20 is used to guide the working medium to flow in a spiral direction, and the direction is changed by the bending structure 202, so as to increase the contact area between the gas-liquid mixture and the wall of the flow channel. At the same time, the surface tension of the liquid droplets in the gas-liquid mixture and the centrifugal force of the swirl flow channel 20 are used to make the gas-liquid mixture move centrifugally to promote gas-liquid separation, thereby promoting the gas-liquid conversion efficiency and ensuring the stability and safety of the entire system. A bending structure 202 is further provided, and when the gas-liquid mixture flows to the bending structure 202, the liquid droplets in the gas-liquid mixture collide and converge on the wall of the bending structure 202, so that the liquid droplets stay in the flow channel, which can help separate the gas-liquid mixture, and further ensure the purity of the outflowing gas through gas-liquid separation.

[0045] As a result, for the evaporator 30, the time that the liquid stays in the evaporator 30 is increased, and there is more sufficient heat exchange time between the liquid working medium and the heating element, which improves the heat absorption efficiency and heat absorption effect of the working medium, transfers the heat generated by the heating element in time, and improves the heat absorption capacity of the two-phase flow heat exchange system. For the condenser 40, the swirl flow channel 20 is used to achieve gas-liquid separation, and the separated gas further dissipates heat and liquefies, ensuring that the liquid accounts for a large proportion of the gas-liquid mixture flowing out of the condenser 40.

[0046] In summary, the two-phase heat exchange structure increases the heat dissipation capacity of the two-phase heat exchange system, and ensures that the drive device 70 can operate safely for a long time, meeting the heat dissipation requirements of extreme environments. Further, the two-phase heat exchange system can be miniaturized and lightweight, so that it can be used in small equipment such as small aircraft, greatly broadening the application scenarios and scope of use of the two-phase heat exchange system.

[0047] In a possible implementation, the evaporation channel 10 includes an inlet area 101, an evaporation tube 102 and an outlet area 103. The inlet area 101 and the outlet area 103 are arranged opposite to each other. The evaporation tube 102 is provided with at least one and is used to connect the inlet area 101 and the outlet area 103. The evaporation tube 102 is provided with the necking structure 104 at one end adjacent to the inlet area 101.

[0048] Based on the above design, there are multiple evaporation tubes 102. Compared with a single large-diameter pipeline, the contact area between the working medium and the pipeline is increased while ensuring the working medium flow rate. The heat exchange area between the working medium and the heating element is larger, and the heat exchange is more sufficient. At the same time, a constriction structure 104 is provided at the entrance of the evaporation tube 102 to enhance the liquid-gas conversion efficiency.

[0049] Accordingly, an inlet area 101 and an outlet area 103 which can be constructed in any suitable shape are provided to realize the connection between the evaporation tube 102 and surrounding components. The inlet area 101 also has a diversion effect, and the outlet area 103 also has a converging effect, so that multiple evaporation tubes 102 can work simultaneously, thereby improving the heat exchange effect and efficiency.

[0050] Alternatively, if Figure 1 , Figure 2 , Figure 5 and Figure 6 As shown, the inlet area 101 and the outlet area 103 can be constructed as a flat structure to provide sufficient space for the connection of multiple evaporation tubes 102, and also make the inlet area 101, multiple evaporation tubes 102 and the outlet area 103 on the same plane, so as to reduce the space occupied by the evaporation flow channel 10, which helps to achieve miniaturization and standardization of related equipment.

[0051] In a possible implementation, the cross-sectional area of ​​the evaporation tube 102 is S1, the cross-sectional area of ​​the constriction structure 104 is S2, and S1 ≥ 2S2. Based on the above design, by limiting the ratio of the cross-sectional area of ​​the evaporation tube 102 to the constriction structure 104, it is ensured that when the working medium flows through the constriction structure 104, a flash effect occurs and turbulence is induced.

[0052] It is easy to understand that when the evaporation channel 10 is applied to the evaporator 30, in order to achieve the flash evaporation effect, the external temperature needs to reach the saturation temperature of the working fluid. In addition to the heat supply of the heating element, a heating component can also be set to ensure that the temperature of the working fluid reaches its saturation temperature when flowing through the necking structure 104.

[0053] In a possible implementation, the swirl flow channel 20 includes a plurality of arc-shaped flow channels 201 and a plurality of bending structures 202; Adjacent arc-shaped flow channels 201 are coaxial and spaced apart so that the plurality of arc-shaped flow channels 201 are located on the same plane; Adjacent arc-shaped flow channels 201 are connected by a bending structure 202, so that the adjacent arc-shaped flow channels 201 are connected to form a spiral pipeline with a single flow direction and a bend; Correspondingly, one of the outermost arc-shaped flow channel 201 and the innermost arc-shaped flow channel 201 is used for the inflow of working fluid, and the other is used for the outflow of working fluid, and both the inflow and outflow of working fluid are provided with additional bending structures 203 for changing the flow direction.

[0054] Based on the above design, multiple arc-shaped flow channels 201 are coaxially arranged, so that the swirl flow channel 20 also has a flat structure, which reduces the space occupied by the swirl flow channel 20, and helps to achieve the miniaturization and standardization of related equipment. From the inside to the outside, multiple arc-shaped flow channels 201 are constructed as a spiral structure, but there is a break between two adjacent arc-shaped flow channels 201, and the bending structure 202 is located at the break and connects the two adjacent arc-shaped flow channels 201, so as to achieve the connection and communication between the two adjacent arc-shaped flow channels 201, and also make the working fluid turn at the bending structure 202.

[0055] In other words, when the working fluid flows along the arc-shaped flow channel 201, the flow speed of the working fluid is fast enough to cause the gas-liquid mixture to produce a centrifugal effect, thereby promoting the separation of the larger mass droplets from the gas, thereby achieving the effect of gas-liquid separation. When the working fluid flows to the bending structure 202, the working fluid turns, and during the turning process, the flowing working fluid will inevitably collide with the bending structure 202. The droplets in the working fluid converge on the bending structure 202 after the collision, forming large droplets and staying at the bending structure 202, helping to improve the separation effect of the working fluid gas-liquid separation. For the entire swirl structure, it effectively increases the contact area between the working fluid and the swirl flow channel 20, thereby utilizing the surface tension of the droplets so that the droplets can be adsorbed on the swirl flow channel 20 as much as possible, thereby achieving liquid-gas separation of the working fluid.

[0056] Similarly, since the swirl flow channel 20 is constructed as a flat structure, the working medium inflow and outflow of the swirl flow channel 20, at least the outflow needs to be provided with an additional bending structure 203, to achieve connection and increase the number of collisions of the working medium. Therefore, the working medium inflow is also preferably provided with an additional bending structure 203 to further increase the number of collisions of the working medium.

[0057] In addition, when the swirl flow channel 20 is applied to the evaporator 30 and a heating component for heating the working fluid is provided in the evaporator 30, the heat of the heating component can also be transferred and heat the swirl flow channel 20. For the droplets remaining on the bending structure 202, they can be vaporized under the joint heating of the heating component and the heat-generating component, thereby improving the gas-liquid conversion rate.

[0058] It is easy to understand that the bending structure 202 and the additional bending structure 203 can be respectively constructed into any suitable shapes.

[0059] In one possible implementation, Figure 3 As shown, a fan-shaped area 204 is provided on the swirl flow channel 20, and the two ends of the arc flow channel 201 are respectively located on both sides of the fan-shaped area 204. Correspondingly, a plurality of bending structures 202 are respectively located on both sides of the fan-shaped area 204 and connect adjacent arc flow channels 201. Based on the above design scheme, the fractures in the plurality of arc flow channels 201 are located in the same area and are interconnected to form the fan-shaped area 204, so that the swirl flow channel 20 has better structural symmetry, more convenient production and manufacturing, and better structural performance.

[0060] Alternatively, if Figure 3 As shown, there are 8 arc-shaped flow channels 201 and they are coaxially arranged from outside to inside. The 8 arc-shaped flow channels 201 are connected by 16 bending structures 202. Accordingly, 2 additional bending structures 203 are also included to respectively connect the outermost arc-shaped flow channel 201 and the innermost arc-shaped flow channel 201.

[0061] It is worth noting that the more times of bending, the better the gas-liquid separation effect, but it will increase the power consumption of the driving device 70. Therefore, in actual use, the number of bending is minimized as long as the gas-liquid separation ratio meets the use requirements.

[0062] Combined with the description of the evaporation flow channel 10 and the swirl flow channel 20, for the two-phase flow heat dissipation structure, the gas-liquid conversion efficiency of the working medium is improved by structural improvement. On the basis of the structural improvement, the two-phase flow heat dissipation structure can also be provided with a functional layer to further improve the gas-liquid conversion efficiency. Specifically: In a possible implementation, an etching layer for matching the necking structure 104 is provided on the evaporation channel 10 , and a sandblasting layer for matching the bending structure 202 is provided on the swirl channel 20 .

[0063] Based on the above design, an etching layer is obtained on the evaporation channel 10 through an etching process, and the etching layer effectively increases the internal roughness and channel surface area of ​​the evaporation channel 10, and promotes the adsorption of droplets in the gas-liquid mixture. And considering that the cross-sectional area of ​​the constriction structure 104 is small, etching can be completed by putting the etching liquid into the constriction structure 104, which solves the difficulty of equipment selection.

[0064] Similarly, a sandblasting layer is obtained on the swirl flow channel 20 through the sandblasting process, and the sandblasting layer effectively increases the internal roughness and flow channel surface area of ​​the swirl flow channel 20, and promotes the adsorption of liquid droplets in the gas-liquid mixture. Considering that the cross-sectional area of ​​the swirl flow channel 20 is relatively large, the sandblasting process can be selected for processing.

[0065] In a possible implementation, the etching layer is obtained by the following steps: S10: preparing an etching solution: preparing a mixture of ferric chloride and hydrochloric acid; S20 etching: adding corrosion inhibitor, and / or, intermittent etching, the intermittent etching adopts etching for 40s, cleaning for 20s and cycle; S30 micro-arc oxidation treatment: obtain an oxide layer of 10μm-20μm.

[0066] Based on this, in the process of obtaining the etching layer, in S10, the required etching solution is configured. It is easy to understand that a mixture of ferric chloride and hydrochloric acid is generally selected. If necessary, any other suitable etching solution can also be prepared according to the actual processing conditions.

[0067] In S20, etching is performed by etching liquid. Before etching, it should be noted that the wall thickness of the evaporation channel 10 must meet the safety requirements of the etching process to avoid the occurrence of etching. During etching, attention should also be paid to the etching situation, and the etching rate and progress can be controlled by adding corrosion inhibitors or intermittent etching to reduce the accumulated heat of the reaction and control the verticality of the wall of the etched groove.

[0068] In S30, after the etching is completed, micro-arc oxidation is performed to increase the hardness of the etched grooves and improve the service life of the etching layer.

[0069] In a possible implementation, the sandblasting layer is obtained by the following steps: The S10 equipment uses: corundum powder with a diameter less than 0.3mm, a low-pressure compressed air system with a pressure of 0.2-0.4MPa, and a flexible micro-spray nozzle with an inner diameter of ≤0.5mm; S20 sandblasting: At the arc-shaped pipe, every 14cm-16cm is divided into a sandblasting section, and sandblasting is performed section by section, and the flexible micro-nozzle nozzle is parallel to the swirl flow channel 20, and the sandblasting angle is 5°-10°; pulse sandblasting is used at the bending structure 202; S30 inspection: surface roughness inspection and flow channel air tightness test; Among them, in S30, the surface roughness of the sandblasting layer needs to reach Ra12.5μm.

[0070] Based on this, in the process of obtaining the sandblasting layer, in S10, suitable equipment is selected, and this embodiment provides a practical implementation plan, namely, corundum powder with a diameter less than 0.3 mm to reduce the probability of gravel blocking the swirl flow channel 20; a low-pressure compressed air system with a pressure of 0.2-0.4 MPa, and a flexible micro-spray nozzle with an inner diameter of ≤0.5 mm to reduce the impact force of gravel during sandblasting and prevent deformation and damage of the swirl flow channel 20.

[0071] Optionally, the corundum powder is generally selected to be 20 μm-50 μm, and other suitable sizes may be selected if necessary.

[0072] In S20, sandblasting is performed by the equipment in S10. Considering that the length of the swirl flow channel 20 is relatively long, sandblasting is performed section by section after partitioning. After each section is completed, its cleanliness needs to be checked before moving on to the next section. During the sandblasting process, the angle of the flexible micro-spray nozzle is controlled to achieve downstream injection to reduce the rebound and accumulation of gravel. For the bending structure 202, which has corners that are prone to fouling, pulse sandblasting is used to improve the sandblasting accuracy, which also helps to eliminate fouling.

[0073] In S30 , the sandblasting layer is inspected to ensure that the sandblasting layer meets the use requirements and that the swirl flow channel 20 has no structural damage.

[0074] Embodiment 2: This embodiment introduces the application of the two-phase flow heat dissipation structure on the basis of the two-phase flow heat dissipation structure described in Embodiment 1. Specifically: like Figure 4 and Figure 5 As shown, an evaporator based on the two-phase flow heat exchange structure comprises a shell 31, a heater 32 and the two-phase flow heat exchange structure; The shell 31 includes a cover plate 301, a steam generator 302 and an evaporator cavity 303 which are arranged in sequence from bottom to top. The heater 32 is arranged on the cover plate 301 and is used to heat the steam generator 302. The two-phase flow heat exchange structure is arranged in the evaporator cavity 303, and the evaporation channel 10 is located between the heater 32 and the swirl channel 20.

[0075] Based on the above design scheme, the evaporator 30 is divided into three parts, namely, the heater 32 located at the bottom, which is used as the bottom heat source; the evaporation flow channel 10 located in the middle, which is used as the middle liquid-gas conversion structure; and the cyclone flow channel 20 located at the top, which is used as the top gas-liquid separation structure.

[0076] When the working medium flows into the evaporator 30, the working medium flows into the evaporation flow channel 10, absorbs heat in the evaporation flow channel 10 and becomes gas, and the working medium changes into a gas-liquid mixture and flows into the cyclone flow channel 20. The gas-liquid mixture flows in the cyclone flow channel 20 and undergoes gas-liquid separation, the gas flows out, and the liquid is temporarily stored. For the temporarily stored liquid, the heat of the heater 32 and / or the heating element is used to evaporate the portion of the liquid.

[0077] It is worth noting that the heater 32 is used to provide heat, and the heater 32 is located at the bottom of the evaporator 30. The heat of the heater 32 is transferred from bottom to top, and the evaporation channel 10 helps to increase the heat exchange area and accelerate the gasification of the working medium. The heater 32, the evaporation channel 10 and the swirl channel 20 are arranged in sequence from bottom to top, so that the heat of the evaporation channel 10 can also be used to heat the liquid in the swirl channel 20. Based on this, the utilization rate of heat is improved and the gas-liquid conversion rate is increased.

[0078] It is easy to understand that the housing 31 is also preferably constructed as a flat structure to reduce the space occupied by the evaporator 30 so as to achieve miniaturization and standardization. The heater 32 and the steam generator 302 can be any suitable existing model.

[0079] Optionally, the heater 32 uses four ceramic heating plates, and the heating power of each ceramic heating plate is between 100 W and 350 W. In one embodiment, the power of each ceramic heating plate is 250 W, with a total heat consumption of 1000 W.

[0080] like Figure 4 and Figure 6 As shown, a condenser based on the two-phase flow heat exchange structure includes the two-phase flow heat exchange structure, wherein the two-phase flow heat exchange structure includes an evaporation flow channel 10 and two parallel swirl flow channels 20, so that the liquid-to-gas ratio of the gas-liquid mixture flowing out of the condenser 40 is ≥94%.

[0081] Based on the above design scheme, the condenser 40 and the evaporator 30 both apply the two-phase flow heat dissipation structure. The functions of the two-phase flow heat dissipation structure in the condenser 40 and the evaporator 30 are different. This difference has been explained in Example 1 and will not be repeated here.

[0082] During operation, after the working medium flows into the condenser 40, it releases heat to the outside and is quickly liquefied in the evaporation channel 10, and the remaining gas in the working medium enters the cyclone channel 20, through which gas-liquid separation is achieved, and at the same time, any suitable heat dissipation equipment such as a heat dissipation fan and heat dissipation fins is used to further liquefy the gas.

[0083] Furthermore, the condenser 40 is different from the evaporator 30 in that the condenser 40 is provided with an evaporation flow channel 10 and two parallel swirl flow channels 20, that is, the number of swirl flow channels 20 is relatively large. Specifically, as the proportion of liquid in the working fluid increases, the flow resistance of the working fluid flowing in the condenser 40 also increases. In order to reduce the influence of the flow resistance and reduce the pressure of the driving device 70, two parallel swirl flow channels 20 are provided to share the working fluid flowing out of the evaporation flow channel 10, thereby greatly reducing the flow resistance.

[0084] It is worth noting that, when two swirl flow channels 20 are provided, the gas-liquid separation effect of the condenser 40 is better, ensuring that the liquid-gas ratio of the gas-liquid mixture flowing out of the condenser 40 is ≥94%. Based on this, the working gas content flowing into the drive device 70 is small, which effectively reduces the damage of cavitation to the drive device 70 and ensures the service life of the drive device 70.

[0085] Similarly, the condenser 40 is also preferably constructed as a flat structure to reduce space occupation so as to facilitate miniaturization and standardization.

[0086] It is easy to understand that in order to improve the heat dissipation efficiency of the condenser 40, the condenser 40 is provided with any suitable heat dissipation equipment such as a heat dissipation fan and heat dissipation fins to ensure that the working fluid flowing into the condenser 40 is fully liquefied so that the liquid-to-gas ratio of the gas-liquid mixture flowing out of the condenser 40 is ≥94%.

[0087] like Figure 1-Figure 7 As shown, a two-phase flow heat exchange system includes the evaporator 30, the condenser 40, the auxiliary port 50, the liquid storage tank 60 and the driving device 70; The evaporator 30, the condenser 40, the auxiliary port 50, the liquid storage tank 60 and the drive device 70 are connected in sequence to form a closed heat dissipation circuit. The liquid filling volume of the heat dissipation circuit is not less than 90%. The evaporator 30 is arranged near the heat source and is used to absorb heat. The auxiliary port 50 is used as a liquid filling port and an inspection port.

[0088] In the two-phase flow heat exchange system, the evaporator 30 and the condenser 40 have been described in combination with the two-phase flow heat exchange structure in Example 1, and the remaining components are described here, specifically: When the auxiliary port 50 is used as a liquid replenishing port, the staff can add an appropriate amount of working fluid into the heat dissipation circuit through the auxiliary port 50 to ensure that the liquid filling amount of the heat dissipation circuit is not less than 90%. When the auxiliary port 50 is used as an inspection port, the staff can inspect the two-phase flow heat exchange system through the auxiliary port 50 to confirm the working condition of the two-phase flow heat exchange system.

[0089] The liquid storage tank 60 is used to store excess liquid in the two-phase flow heat exchange system to maintain system stability and avoid excessive saturation pressure inside the system. It can also achieve gas-liquid two-phase separation to prevent incompletely cooled gas in the system from entering the drive device 70 and causing cavitation to the drive device 70, thereby affecting the performance of other components in the system.

[0090] The driving device 70 is used as a power source and drives the working medium to flow along the heat dissipation circuit. It is easy to understand that the driving device 70 can be any suitable existing equipment.

[0091] During operation, the drive device 70 starts and drives the working fluid to flow. When the working fluid flows to the evaporator 30, the evaporator 30 is close to the heat source, and the working fluid absorbs heat and vaporizes. Based on the application of the two-phase flow heat exchange structure, the evaporator 30 has a high heat absorption efficiency, and the gas content of the working fluid flowing out of the evaporator 30 is high. After flowing out of the evaporator 30, the working fluid flows into the condenser 40, where the working fluid releases heat and liquefies. Based on the application of the two-phase flow heat exchange structure, the condenser 40 has a high heat absorption efficiency, and the liquid content of the working fluid flowing out of the condenser 40 is high. Specifically, the liquid-to-gas ratio of the gas-liquid mixture flowing out of the condenser 40 is ≥94%. After the working fluid flows out of the condenser 40, it flows into the liquid storage tank 60 and undergoes gas-liquid separation, and then flows into the drive device 70.

[0092] Therefore, for the working fluid state in the heat dissipation circuit, Figure 4 As shown, the working medium flows out of the evaporator 30 and flows into the condenser 40, which is a gas section mainly composed of gas. Conversely, the working medium flows out of the condenser 40 and flows into the evaporator 30, which is a liquid section mainly composed of liquid.

[0093] For the extreme working conditions described in Example 1, take an aircraft at high altitude and multi-angle acceleration as an example. Compared with the conventional vehicle environment, the movement of the aircraft has differences such as multi-angle acceleration and random vibration, and the flow of the working fluid will also be affected by the state of the aircraft. For example, when the aircraft accelerates, the working fluid in the heat dissipation circuit will be chaotically distributed, and the working fluid will gather, especially the liquid working fluid, causing the two-phase flow heat exchange system to fail to work normally and the heat dissipation effect to be discounted; even if a large amount of gaseous working fluid enters the drive device 70, the drive device 70 will be damaged due to cavitation, causing the two-phase flow heat exchange system to fail to work.

[0094] In this regard, by controlling the amount of liquid filled in the heat dissipation circuit, it is ensured that there is enough working fluid flowing in the design direction in the heat dissipation circuit. At the same time, through the application of the two-phase flow heat exchange structure, the working efficiency of the evaporator 30 and the condenser 40 is improved, ensuring that even under extreme working conditions, the working fluid in the liquid section is mainly liquid, effectively protecting the drive device 70. In addition, a liquid storage tank 60 is provided for controlling the amount of liquid filled in the heat dissipation circuit. Before the working fluid enters the drive device 70, the working fluid is separated into gas and liquid to minimize the gas entering the drive device 70. The liquid storage tank 60 can also store excess liquid to maintain the stability and safety of the two-phase flow heat exchange system.

[0095] Based on this, the two-phase heat exchange system achieves efficient heat dissipation, greatly improves the heat dissipation capacity and environmental adaptability of the two-phase heat exchange system, and effectively expands the scope of use of the two-phase heat exchange system. Compared with existing two-phase heat dissipation equipment, the two-phase heat exchange system also eliminates the gas-liquid separator, which helps to reduce weight, reduce volume, and achieve miniaturization and lightweight design.

[0096] Preferably, in the two-phase flow heat exchange system, argon arc welding is used to achieve connection and sealing at each interface to improve the pressure bearing capacity and reliability of the system.

[0097] Preferably, the two-phase flow heat exchange system adopts a modular concept in the design and production process, so as to manufacture products of different specifications, and the staff can select products of appropriate specifications according to actual working conditions.

[0098] In a possible implementation, the liquid storage tank 60 includes a tank body 61 and an extraction channel 62; The tank body 61 has an upper cavity 601 and a lower cavity 602 which are opposite to each other. The upper cavity 601 is provided with a deflation valve 603 and an inlet 604, and the lower cavity 602 is provided with an outlet 605. Correspondingly, the inlet 604 and the outlet 605 are respectively connected with pipelines, and the extraction flow channel 62 is located between the upper cavity 601 and the lower cavity 602. The outer periphery of the extraction flow channel 62 is provided with spiral downward fins 606, and the outer peripheral surface of the extraction flow channel 62 is close to the inner peripheral surface of the tank body 61, so that a one-way flow channel is formed between two adjacent fins 606, and the one-way flow channel is tangent to the inlet 604 and the outlet 605, so that the working medium flows in and out along the tangential direction; Correspondingly, the upper and lower ends of the extraction channel 62 are respectively provided with additional pipelines 607 tangent to the one-way channel.

[0099] Based on the above design scheme, the spiral ribs 606 in the liquid storage tank 60 cooperate with the tank body 61 to form a spiral one-way flow channel. The function of the one-way flow channel is similar to that of the vortex flow channel 20, that is, it is used to separate gas and liquid in the working fluid. The difference between the two is that the liquid-to-gas ratio of the gas-liquid mixture flowing out of the condenser 40 is ≥94%, so the one-way flow channel does not need to be provided with a bending structure 202.

[0100] It is worth noting that the liquid storage tank 60 limits the flow direction of the working fluid, that is, it flows from top to bottom. The working fluid is affected by gravity and flows downward. Since the working fluid flows along the spiral flow channel, under the action of centrifugal force, the gas and liquid will be separated to a certain extent. At the same time, for the liquid contacting the surface of the one-way flow channel, the contact area between the two is large, and the liquid is easily adsorbed on the one-way flow channel under the action of surface tension, which further improves the effect of gas-liquid separation. For this part of the liquid, it may also flow into the lower cavity 602 of the liquid storage tank 60 and be stored. In addition, the working fluid flows in a tangential direction, giving the working fluid a tangential speed along the fins 606, making it easier for the liquid to swirl along the fins 606 inside the liquid storage tank 60 and flow out of the outlet 605 of the liquid storage tank 60, thereby improving the efficiency of gas-liquid separation in the liquid storage tank 60.

[0101] On the contrary, if the liquid flows from bottom to top, the working fluid will fill the entire liquid storage tank 60 before flowing out from the top of the liquid storage tank 60, so that most of the working fluid in the heat dissipation circuit is stored in the liquid storage tank 60, which greatly reduces the amount of liquid in the heat dissipation circuit, but seriously affects the operation of the two-phase flow heat exchange system. In addition, when the liquid fills the liquid storage tank 60, the gas and liquid in the remaining working fluid will flow out of the liquid storage tank 60, so that the liquid storage tank 60 cannot achieve the function of gas-liquid separation.

[0102] The liquid storage tank 60 is provided with a vent valve 603 to timely release the gas retained in the liquid storage tank 60, thereby reducing the amount of dissolved gas in the entire heat dissipation circuit and effectively preventing the liquid storage tank 60 from being over-pressurized.

[0103] It is easy to understand that the inlet 604 and the outlet 605 of the tank body 61 are respectively connected to pipes, and accordingly, an additional pipe 607 is provided on the extraction channel 62. When the extraction channel 62 is located in the tank body 61, the additional pipe 607 is plugged into the adjacent pipe, and the additional pipe 607 is used to guide the flow direction of the working fluid to ensure that the working fluid flows in and out tangentially.

[0104] Embodiment 3: Based on Example 2, this example conducts tests in a vibration environment and an acceleration environment respectively to verify the effect of the two-phase flow heat exchange system described in Example 2.

[0105] 1. Taking an aircraft in a vibration environment as an example, the heat dissipation effect of the two-phase flow heat exchange system under extreme working conditions is explained: The direction of the system is defined as Figure 8 As shown in the figure, the random vibration method is used to study the vibration resistance of a typical airborne electronic equipment functional vibration environment. The vibration spectrum is shown in Fig. 9 As shown, the vibration value is 10.45G, the system thermal input conditions under the vibration environment are the same as the thermal input conditions of the system thermal test under normal conditions, and the vibration directions are X, Y, and Z directions.

[0106] like Figure 10-12 As shown in the figure, the temperature change curve of the two-phase flow cooling system when working under vibration environment conditions. From the experimental results, it can be seen that the influence of vibration on the thermal performance of the system is small. In the X and Y direction vibration, the temperature change before and after the test is less than 2°C, which has little influence; in the Z direction vibration, the temperature change before and after the test is less than 5°C, which is slightly larger than the temperature difference in the X and Y direction vibration. This is mainly because the heat source is installed in the Z direction of the evaporator 30, and the Z direction vibration reduces the contact performance between the internal fluid of the system and the internal wall of the evaporator 30, and the heat transfer performance is reduced.

[0107] In summary, it can be seen that in a complex vibration environment, the two-phase flow heat exchange system reduces the impact of vibration on the heat dissipation performance of the system, effectively maintains the heat dissipation capacity, and ensures that the heating element can work normally under extreme working conditions.

[0108] 2. Taking an aircraft in an acceleration environment as an example, the heat dissipation effect of the two-phase flow heat exchange system under extreme working conditions is explained: The two-phase heat exchange system described in Example 2 was used as the experimental group, and any existing two-phase heat dissipation system was used as the control group. The test was conducted on the same aircraft, and multiple tests were conducted under conditions of multi-angle acceleration and gravitational acceleration greater than 1G. Specifically: The control group conducted experiments and obtained relevant data, i.e. Figure 13-Figure 16 As shown in the figure, the temperature change curves of the system under the acceleration environment of X+, X-, Y+ and Y- directions respectively. The heat input conditions of the system under the acceleration environment are the same as the heat input conditions of the system thermal test under room temperature. The acceleration direction of the system is defined the same as the vibration realization direction, and the acceleration test time is 1 minute. When performing the acceleration test in the Z direction, since the system needs to be installed sideways, the liquid storage and liquid distributor is installed horizontally, and the liquid in the liquid storage and liquid distributor cannot flow back normally. The liquid in the system gathers at the bottom of the system, and the gas circulates in the system, which makes the system unable to work normally and cannot perform the Z direction acceleration test.

[0109] During the test, the external forces on the fluid inside the liquid storage dispenser are mainly the resistance caused by gravity and acceleration. The fluid inside the liquid storage dispenser is affected by two different external forces, resulting in a complex gas-liquid distribution. According to the measured data analysis, under the influence of acceleration in the X-, Y+, and Y- directions, the temperature of the heat source fluctuates greatly and the temperature changes greatly; while under the influence of acceleration in the X+ direction, the temperature of the heat source changes slightly. At the same time, during the acceleration experiments in the X-, Y+, and Y- directions, it was found that the driving current of the system drive pump decreased sharply. In the X- acceleration experiment, the driving current of the system drive pump decreased from 0.7A to 0.38A; in the Y+ acceleration experiment, the driving current of the system drive pump decreased from 0.7A to 0.4A; in the Y- acceleration experiment, the driving current of the system drive pump decreased from 0.7A to 0.41A. In the X+ acceleration test, the driving current of the system drive pump did not decrease sharply, and the driving current of the system drive pump remained fluctuating around 0.7A.

[0110] Because in an acceleration environment, the system driving pump has a large driving force to overcome the acceleration resistance to drive the normal flow of the internal fluid in the pipeline. However, in the liquid reservoir separator, since the system relies on centrifugal force to achieve gas-liquid separation of the fluid, it will completely fail under the action of the external force of acceleration, and the gas and liquid distribution inside the liquid reservoir separator will become chaotic. The fluid flowing out of the outlet of the liquid reservoir separator into the system return pipeline may be liquid or gas. When the direction of acceleration is opposite to the flow direction of the liquid inside the liquid reservoir separator, the liquid inside the liquid reservoir separator gathers in the liquid reservoir separator, and the main fluid entering the pipeline is gas, and the system fails; when the direction of acceleration is the same as the flow direction of the liquid inside the liquid reservoir separator, the main fluid entering the pipeline is liquid, and the system works normally.

[0111] According to the analysis, this is mainly because the internal fluid of the liquid storage and liquid distributor is affected by the acceleration resistance, and the internal liquid has the following Fig.17 Liquid distribution shown. Under acceleration in the X+ direction, the outlet of the liquid storage and liquid distributor is all liquid, so the fluid entering the system return pipeline is liquid, and the system thermal performance will not fluctuate greatly. Under acceleration conditions in other directions, the outlet of the liquid storage and liquid distributor is a gas-liquid mixture, and the gas enters the system pipeline, causing large fluctuations in the system thermal performance. At the same time, the input current of the mechanical pump decreases. The main reason is that there is a lot of gas in the fluid in the system return pipeline, the system resistance is small, and the driving force required for the mechanical pump to drive the gas is smaller than that required to drive the liquid, resulting in a significant reduction in the input current of the mechanical pump.

[0112] It is easy to understand that in the control group experimental records, the system refers to any existing two-phase flow heat dissipation system, and the system driving pump, liquid storage distributor, pipelines, etc. are all components of any existing two-phase flow heat dissipation system.

[0113] The experimental group conducts experiments and obtains relevant data, i.e. Figure 18-Figure 23 The figure shows the thermal performance curve of the acceleration test system after changing the system filling volume. It can be seen from the test data that under the action of various accelerations, the system heat source temperature does not rise in a concentrated manner, the temperature fluctuation curve is relatively smooth, the driving current of the driving device 70 does not decrease sharply, and the system works normally.

[0114] Combined with the analysis of the control group, in the existing two-phase flow heat dissipation system, the liquid storage separator uses the centrifugal principle to separate gas and liquid. Under the influence of indefinite direction acceleration, the distribution of the fluid inside the existing two-phase flow heat dissipation system changes with the change of acceleration direction. Specifically, under the influence of acceleration, the liquid inside the liquid storage separator cannot flow back to the return pipe of the existing two-phase flow heat dissipation system, causing the existing two-phase flow heat dissipation system to fail.

[0115] In view of this, in the experimental group, the two-phase flow heat exchange system in Example 2, on the one hand, improved the structure of the evaporator 30, the condenser 40 and the liquid storage tank 60, and on the other hand, increased the liquid filling volume in the two-phase flow heat exchange system, thereby effectively improving the cooling and heat dissipation efficiency of the two-phase flow heat exchange system under the accelerated state, as well as the stability and reliability of the system operation.

[0116] Based on this, in an acceleration environment, when the liquid filling amount of the two-phase flow heat exchange system is less than the volume of the liquid storage tank 60, when the acceleration direction causes the liquid in the two-phase flow heat exchange system to mainly accumulate in the liquid storage tank 60, there is less liquid flowing in the heat dissipation circuit, resulting in system failure; when the liquid filling amount of the two-phase flow heat exchange system is greater than the volume of the liquid storage tank 60, when the two-phase flow heat exchange system is under the influence of acceleration in the opposite direction, that is, the liquid accumulates in the liquid storage tank 60, but when the liquid fills the liquid storage tank 60, the excess liquid will circulate in the heat dissipation circuit under the action of the driving device 70, thereby avoiding failure of the two-phase flow heat exchange system.

[0117] In summary, it can be seen that in an acceleration environment, especially under conditions of multi-angle acceleration and gravitational acceleration greater than 1G, the two-phase flow heat exchange system effectively overcomes the influence of acceleration on the heat dissipation capacity of the system, effectively maintains the heat dissipation capacity, and ensures that the heating elements can work normally under extreme working conditions.

[0118] The specific implementation methods described above further illustrate the objectives, technical solutions and beneficial effects of the present invention in detail. It should be understood that the above description is only a specific implementation method of the present invention and is not intended to limit the scope of protection of the present invention. Any modifications, equivalent substitutions, improvements, etc. made within the spirit and principles of the present invention should be included in the scope of protection of the present invention.

Claims

1. A two-phase flow heat exchange structure, characterized in that: It comprises an evaporation flow channel (10) and a swirl flow channel (20) connected to each other; The evaporation flow channel (10) has a constriction structure (104) for promoting gas-liquid conversion; The cyclone flow channel (20) has a bending structure (202) for separating gas and liquid.

2. The two-phase flow heat exchange structure according to claim 1, characterized in that: The evaporation flow channel (10) comprises an inflow area (101), an evaporation tube (102) and an outflow area (103); the inflow area (101) and the outflow area (103) are arranged opposite to each other; the evaporation tube (102) is provided with at least one and is used to connect the inflow area (101) and the outflow area (103); and the shrinkage structure (104) is provided at one end of the evaporation tube (102) adjacent to the inflow area (101).

3. The two-phase flow heat exchange structure according to claim 2, characterized in that: The cross-sectional area of ​​the evaporation tube (102) is S1, the cross-sectional area of ​​the necking structure (104) is S2, and S1≥2S2.

4. The two-phase flow heat exchange structure according to claim 1, characterized in that: The swirl flow channel (20) comprises a plurality of arc-shaped flow channels (201) and a plurality of bending structures (202); Adjacent arc-shaped flow channels (201) are coaxial and spaced apart, so that the plurality of arc-shaped flow channels (201) are located on the same plane; Adjacent arc-shaped flow channels (201) are connected via a bending structure (202) so that the adjacent arc-shaped flow channels (201) are connected to form a spiral pipeline with a single flow direction and a bend; Correspondingly, one of the outermost arc-shaped flow channel (201) and the innermost arc-shaped flow channel (201) is used for the inflow of working fluid, and the other is used for the outflow of working fluid, and both the inflow and outflow of working fluid are provided with additional bending structures (203) for changing the flow direction.

5. The two-phase flow heat exchange structure according to claim 4, characterized in that: A fan-shaped area (204) is provided on the swirl flow channel (20), and two ends of the arc-shaped flow channel (201) are respectively located on both sides of the fan-shaped area (204). Correspondingly, a plurality of bending structures (202) are respectively located on both sides of the fan-shaped area (204) and connect adjacent arc-shaped flow channels (201).

6. The two-phase flow heat exchange structure according to any one of claims 1 to 5, characterized in that: An etching layer for matching the necking structure (104) is provided on the evaporation flow channel (10), and a sandblasting layer for matching the bending structure (202) is provided on the swirl flow channel (20); The etched layer is obtained by the following steps: S10: preparing an etching solution: preparing a mixture of ferric chloride and hydrochloric acid; S20 etching: adding corrosion inhibitor, and / or, intermittent etching, the intermittent etching adopts etching for 40s, cleaning for 20s and cycle; S30 micro-arc oxidation treatment: obtain an oxide layer of 10μm-20μm; The sandblasting layer is obtained by the following steps: The S10 equipment uses: corundum powder with a diameter less than 0.3mm, a low-pressure compressed air system with a pressure of 0.2-0.4MPa, and a flexible micro-spray nozzle with an inner diameter of ≤0.5mm; S20 sandblasting: At the curved pipe, every 14 cm to 16 cm is divided into a sandblasting section, and sandblasting is performed section by section, and the flexible micro-spray nozzle is parallel to the swirl flow channel (20), and the sandblasting angle is 5° to 10°; pulse sandblasting is used at the bending structure (202); S30 inspection: surface roughness inspection and flow channel air tightness test; Among them, in S30, the surface roughness of the sandblasting layer needs to reach Ra12.5μm.

7. An evaporator based on the two-phase flow heat exchange structure according to any one of claims 1 to 6, characterized in that: It comprises a shell (31), a heater (32) and the two-phase flow heat exchange structure; The shell (31) comprises a cover plate (301), a steam generator (302) and an evaporator cavity (303) which are arranged in sequence from bottom to top; the heater (32) is arranged on the cover plate (301) and is used to heat the steam generator (302); the two-phase flow heat exchange structure is arranged in the evaporator cavity (303); and the evaporation flow channel (10) is located between the heater (32) and the swirl flow channel (20).

8. A condenser based on the two-phase flow heat exchange structure according to any one of claims 1 to 6, characterized in that: The two-phase heat exchange structure comprises an evaporation flow channel (10) and two parallel swirl flow channels (20), so that the liquid-to-gas ratio of the gas-liquid mixture flowing out of the condenser (40) is ≥94%.

9. A two-phase flow heat exchange system, characterized in that: It comprises the evaporator (30) according to claim 7, the condenser (40) according to claim 8, an auxiliary port (50), a liquid storage tank (60) and a driving device (70); The evaporator (30), the condenser (40), the auxiliary port (50), the liquid storage tank (60) and the drive device (70) are connected in sequence to form a closed heat dissipation circuit. The liquid filling volume of the heat dissipation circuit is not less than 90%. The evaporator (30) is arranged near the heat source and is used to absorb heat. The auxiliary port (50) is used as a liquid filling port and an inspection port.

10. The two-phase flow heat exchange system according to claim 9, characterized in that: The liquid storage tank (60) comprises a tank body (61) and an extraction flow channel (62); The tank body (61) comprises an upper cavity (601) and a lower cavity (602) which are opposite to each other. The upper cavity (601) is provided with an air release valve (603) and an inlet (604), and the lower cavity (602) is provided with an outlet (605). Correspondingly, the inlet (604) and the outlet (605) are respectively connected to pipelines. The extraction flow channel (62) is located between the upper cavity (601) and the lower cavity (602). The outer periphery of the extraction flow channel (62) is provided with fins (606) spiraling downward, and the outer peripheral surface of the extraction flow channel (62) is closely attached to the inner peripheral surface of the tank body (61), so that a one-way flow channel is formed between two adjacent fins (606), and the one-way flow channel is tangent to both the inlet (604) and the outlet (605), so that the working fluid flows in and out in a tangential direction; Correspondingly, the upper and lower ends of the extraction flow channel (62) are respectively provided with additional pipes (607) that are tangent to the one-way flow channel.

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