Pump-driven phase change liquid cooling heat dissipation structure

Abstract

The utility model relates to a kind of pump drives phase change liquid cooling heat dissipation structure, it is to solve the liquid cooling server node of existing similar product and corresponding secondary side liquid supply pipeline and internal evaporator structure design are not good, leading to the problem of low heat exchange heat dissipation efficiency.Its main point is that the structure is divided into primary side heat exchange unit and secondary side heat exchange unit, cabinet door one side frame in cabinet is equipped with distribution unit, quick coupling of distribution unit is connected with liquid cooling server node in cabinet by pipeline and secondary side liquid supply pipeline respectively, heat dissipation component in the box of liquid cooling server node and evaporator are attached contact heat transfer, the base of evaporator and the cover body on the setting base are sealed and surrounded to form evaporator cavity, the inlet and outlet structure of inlet and outlet pipe of liquid supply pipe are formed by the joint of different pipe diameter, phase change liquid is filled in evaporator cavity, phase change liquid is phase change liquid cooling medium, evaporator includes the joint of larger and smaller two kinds of pipe diameters, phase change heat exchange unit is equipped with phase change working fluid pump.

Description

Technical Field

[0001] This utility model relates to a heat dissipation device for servers, specifically a pump-driven phase change liquid cooling structure. Background Technology

[0002] Cooling devices refer to the devices used in mechanical equipment, metal cabinets, circuit boards, and other equipment components to quickly dissipate heat, thereby ensuring the normal operation of the equipment components. These include components such as cooling fans, heat sinks, cooling towers, condensate pipes, and liquid cooling plates. With the development of technology in the electronics field, the power consumption of electronic chips and electrical components such as CPUs and GPUs in servers is increasing. Current server cooling devices are generally finned plate assemblies, or cooling door assemblies with heat exchangers installed on the finned plate assemblies of the door. Simultaneously, with the emergence of AI servers, computing density is rapidly increasing, from 0.3kW per chip in 2021 to 1kW in 2025 and 2.8kW+ in the future. The power of the entire server cabinet is increasing from 15kW / cabinet in 2000 to 50kW in 2025 and 120kW+ in the future. The server industry's cooling solutions are transitioning from mainstream air cooling to single-phase water cooling as the primary solution. With the development of data centers, especially the development of technologies such as 5G and AI, the heat dissipation of equipment and data centers is increasing day by day. According to research, carbon emissions related to IT / telecommunications have become one of the largest sources of greenhouse gas emissions, and the emission momentum in this field is rising rapidly with the global demand for computing, data storage and communication technologies. Even though people are making great efforts to improve the energy efficiency of equipment, data center structures and other facilities and data centers, more and more people are beginning to pay attention to the construction of green data centers.

[0003] Currently, the Power Usage Effectiveness (PUE) value of a server rack has become an internationally accepted metric for measuring the power efficiency of data centers. PUE refers to the ratio of all energy consumed by a data center to the energy consumed by IT loads. The closer the PUE value is to 1, the higher the greenness of a data center. To ensure the normal operation of products, previous cooling technologies need to further improve heat dissipation and greenness. Air cooling solutions require higher-specification cooling fans to meet the heat dissipation requirements when dealing with the increasing power consumption of chips, and their PUE is usually 1.5 or higher. However, higher-specification fans also bring greater noise. In the search for alternatives to air cooling, single-phase water cooling solutions are gradually becoming the mainstream server cooling solutions, with a PUE value that can be controlled at 1.25. However, single-phase water cooling has poor reliability and the risk of coolant leakage. For example, Chinese patent application number 201510144752.X, published on June 10, 2015, entitled "Server Heat Dissipation System Combining Air-cooled Natural Cooling Heat Pipe Air Conditioner and Liquid Cooling Device"; and another example, Chinese patent application number 201510144774.6, published on June 10, 2015, entitled "Server Heat Dissipation System Combining Water-ring Natural Cooling Heat Pipe Air Conditioner and Liquid Cooling Device". Therefore, there is a need to provide a more reliable, higher-performance, and more environmentally friendly system solution. Summary of the Invention

[0004] To overcome the aforementioned shortcomings, the purpose of this utility model is to provide a pump-driven phase change liquid cooling structure that addresses the technical problems of poor safety, reliability, stability, and environmental friendliness in existing similar products, particularly the suboptimal design of their liquid-cooled server nodes, corresponding secondary-side liquid supply pipelines, and internal evaporator structures, which result in low heat exchange and heat dissipation efficiency. This objective is achieved through the following technical solution.

[0005] A pump-driven phase change liquid cooling structure is disclosed. The structure includes a liquid distribution unit on one side of the cabinet door frame. Quick-connect fittings of the distribution unit connect to liquid-cooled server nodes within the cabinet via pipelines and secondary-side liquid supply pipelines. Ball valves regulate the liquid supply pipelines on one side of the liquid-cooled server nodes. The cabinets of the liquid-cooled server nodes, which are pushed into the cabinet one by one, are positioned between the two side frames of the cabinet via sliding rail assemblies on both sides of the outer diameter of the cabinet. The key design feature is that the structure consists of a primary-side heat exchange unit and a secondary-side heat exchange unit. These two interconnected and relatively independent circulation systems are connected by a phase change heat exchange unit, which acts as a bridge between the primary and secondary heat exchange units. The secondary heat exchange unit performs heat exchange; the secondary heat exchange unit includes components to be cooled, an evaporator, a secondary liquid supply pipeline, a liquid distribution unit, a phase change heat exchange unit, and a pump for the phase change working fluid, forming an indoor circulation loop. The components to be cooled inside the liquid-cooled server node are in close contact with the evaporator for heat transfer, completing the heat output and exchange from the secondary heat exchange unit to the primary heat exchange unit; the primary heat exchange unit includes an outdoor cooling tower, a primary liquid supply pipeline, and a phase change heat exchange unit, forming an outdoor circulation loop to dissipate the heat exchanged by the secondary heat exchange unit to the atmosphere; the phase change heat exchange unit and the liquid distribution unit are connected by pipelines, and the phase change heat exchange unit and the outdoor cooling tower are connected by water pipes.

[0006] The evaporator base and the cover on the base are sealed together to form an evaporation chamber. The liquid inlet and outlet pipes are connected by connectors of different diameters to form a liquid inlet and liquid outlet structure. The evaporation chamber is filled with phase change liquid, which is a phase change liquid cooling medium. The heat transfer component is brought into contact with the evaporator cover for heat transfer. The phase change liquid in the evaporation chamber absorbs the heat transferred from the evaporator cover through contact and rises in temperature. After reaching the boiling point, boiling heat transfer occurs.

[0007] This structure integrates the components to be cooled, the evaporator, and the secondary-side liquid supply pipe into the liquid-cooled server node. The liquid supply pipe uses quick-connect couplings to form a small sealed unit for filling with phase change fluid. This unit connects to the quick-connect couplings of the distribution unit to form a loop. The distribution unit is connected in parallel to one or more liquid-cooled server nodes, forming a parallel cooling terminal for the secondary-side heat exchange unit. The distribution unit consists of input and output pipelines. Through the secondary-side liquid supply pipeline, the output end connects to the phase change heat exchange unit via a quick-connect coupling. The high-temperature gas-liquid phase change fluid output is condensed in the phase change heat exchange unit, turning it into a lower-temperature liquid. The lower-temperature liquid phase change fluid is then pumped through the secondary-side liquid supply pipeline to the phase change working fluid of the phase change heat exchange unit to drive the phase change fluid cooling medium. The cooled liquid is then fed into the distribution unit through the supply pipeline and into the evaporator in each liquid-cooled server node, circulating and carrying away the heat from the components to be cooled, completing the secondary-side heat transfer loop.

[0008] The evaporator base is provided with capillary structures and / or dense fins, thereby giving it high thermal conductivity and high hydrophilicity, forming a saturation value, increasing the boiling intensity of the phase change liquid in the evaporation chamber of the evaporator, further accelerating the heat exchange efficiency and improving the heat dissipation efficiency.

[0009] The evaporator base has capillary structures and / or dense fins disposed within sheet metal stamped flow channel structures. The dense fins are sheet metal stamped inner fin assemblies, and the heat source is attached to both sides of the corresponding sheet metal stamped flow channel structures.

[0010] The evaporator is equipped with an inlet and an outlet. The inlet is used for liquid inlet and is connected to the liquid inlet pipe using a connector with a smaller diameter. The outlet is a gas-liquid mixing channel and is connected to the liquid outlet pipe using a connector with a larger diameter to accommodate the volume expansion caused by the vaporization of the working fluid.

[0011] The evaporators are symmetrically arranged and connected to the secondary liquid supply pipeline via a Y-shaped liquid supply pipe formed by a three-way fitting. One side of the evaporator may have external heat dissipation fins. The above is the optimal specific structural embodiment for two sets of evaporators. Alternatively, more than two sets of evaporators can be combined as needed and connected via corresponding three-way, four-way, or other pipe fittings.

[0012] The evaporator cover is integrated with the base via six spring-loaded screws arranged symmetrically in pairs on both sides or four locking blocks arranged symmetrically in pairs with latches. The top center of the locking block has a protruding screw post. The retaining spring at one end of the latch is fitted into the screw post, and the other end is hinged and fixed to one side of the locking block below the screw post. The hinge of the retaining spring extends out of the hinge hole on the other side in an L-shape and then bends above the groove at the cover. The base has symmetrically arranged retaining plates on both sides. The two ends of the retaining plates have upward protruding and oppositely arranged hooks. The top of the cover has equidistant positioning screws that extend out. The bottom of the component to be cooled is inserted into the positioning screws. The two end corners of the component to be cooled in the above structure can also be provided with corresponding notches, and further fixed to the top of the cover by the buckle of the buckle plate; when the bottom of the component to be cooled is attached to the top of the cover, the buckle spring is further inserted into the buckle groove at the bottom of the component to be cooled, and the buckle is deformed when pressed down, and the component to be cooled is locked to the cover by the buckle.

[0013] The phase change liquid cooling medium includes a low-boiling-point working fluid, which includes a dielectric fluid. This low-boiling-point dielectric fluid has low density, boiling point, surface tension, and viscosity, and it is easy to evaporate, resulting in high heat exchange efficiency and improved heat dissipation. For server boards, the phase change liquid cooling medium has insulating and low-boiling-point characteristics, avoiding the risk of damage to server equipment caused by leakage in traditional water cooling systems.

[0014] The liquid supply pipe and corresponding piping are made of flexible tubing. This allows for adaptable deformation of the liquid supply pipe and corresponding piping during installation, making the installation of the heat dissipation device more flexible and adaptable. At the same time, the flexible material is made of rubber, which will not chemically react with the dielectric fluid, avoiding damage to the piping and preventing leakage.

[0015] The phase change heat exchange unit primarily employs plate heat exchange, and is equipped with a pump for the phase change working fluid. Therefore, the flow of the working fluid in this structure is active and driven by the pump; unlike traditional phase change heat exchange units which are passively driven by gravity or capillary structures, this design achieves better circulation and improves heat exchange efficiency.

[0016] This utility model has a reasonable structural design, a high degree of integration, high heat exchange and heat dissipation efficiency, and is convenient to use and install, especially for easy pipe installation and removal; it is suitable for use as a pump-driven phase change liquid cooling structure for servers, as well as for structural improvements of similar products. Attached Figure Description

[0017] Figure 1 This is a schematic diagram illustrating the working principle of an embodiment of this utility model.

[0018] Figure 2 yes Figure 1 This is a schematic diagram of the overall structure of the server rack in use. The cabinet doors and door panels are omitted in the diagram.

[0019] Figure 3 yes Figure 1 An enlarged structural diagram of the liquid-cooled server node and the secondary-side liquid supply pipeline in combination.

[0020] Figure 4 yes Figure 3 This is a schematic diagram of the internal structure of a liquid-cooled server node with the case cover open. The components to be cooled on the evaporator cover are omitted from the diagram.

[0021] Figure 5 yes Figure 4 Enlarged structural diagram of the secondary side liquid supply pipeline and evaporator combined.

[0022] Figure 6 yes Figure 5 A magnified schematic diagram of the evaporator structure.

[0023] Figure 7 yes Figure 5 A schematic diagram of the evaporator in the open state.

[0024] Figure 8 yes Figure 4 A schematic diagram of the improved evaporator structure in the open state, with part A outlined in the diagram.

[0025] Figure 9 yes Figure 8 Enlarged view of part A.

[0026] Figure 10 yes Figure 8 This is a schematic diagram of the internal structure of the evaporator housing under operating conditions. The heat dissipation components on the evaporator cover are omitted from the diagram.

[0027] Attached figures and their names: 1. Cabinet, 2. Liquid-cooled server node, 3. Secondary side liquid supply pipeline, 4. Liquid distribution unit, 5. Phase change heat exchange unit, 6. Outdoor cooling tower, 7. Primary side heat exchange unit, 8. Secondary side heat exchange unit, 9. Evaporator, 10. Liquid inlet pipe, 11. Liquid outlet pipe, 12. Cover, 13. Base, 14. Mounting plate, 15. Positioning screw, 16. External heat dissipation fins. Implementation

[0028] The structure and use of this utility model will now be further described with reference to the accompanying drawings. Figures 1-10 As shown, the cabinet 1 of this structure has a liquid distribution unit 4 on one side of the cabinet door frame. The quick connector of the liquid distribution unit is connected to the liquid-cooled server node 2 in the cabinet through the pipeline and the secondary side liquid supply pipeline 3 respectively. The liquid supply pipeline of the secondary side liquid supply pipeline on one side of the liquid-cooled server node is equipped with a ball valve regulating pipeline. The cabinet of the liquid-cooled server node, which is pushed into the cabinet one by one, is set between the two side frames of the cabinet through the slide rail assembly on both sides of the outer diameter of the cabinet. The structure is divided into a primary heat exchange unit 7 and a secondary heat exchange unit 8. The primary and secondary heat exchange units are two interconnected and relatively independent circulation systems, connected by a phase change heat exchange unit 5. The secondary heat exchange unit includes components to be cooled, an evaporator 9, a secondary liquid supply pipeline, a liquid distribution unit, a phase change heat exchange unit, and a pump for the phase change working fluid, forming an indoor circulation loop. The components to be cooled inside the liquid-cooled server node are in close contact with the evaporator for heat transfer, completing the heat output and exchange from the secondary heat exchange unit to the primary heat exchange unit. The primary heat exchange unit includes an outdoor cooling tower 6, a primary liquid supply pipeline, and a phase change heat exchange unit, forming an outdoor circulation loop to dissipate the heat exchanged by the secondary heat exchange unit to the atmosphere. The phase change heat exchange unit is connected to the liquid distribution unit via pipelines, and the phase change heat exchange unit is connected to the outdoor cooling tower via water pipes.

[0029] The evaporator base 13 and the cover 12 mounted on the base form an evaporation chamber. A liquid inlet pipe 10 and a liquid outlet pipe 11, connected by connectors of different diameters, form the liquid inlet and outlet structures, respectively. The evaporation chamber is filled with a phase change liquid, which serves as the cooling medium. The component to be cooled is brought into contact with the evaporator cover for heat transfer. The phase change liquid in the evaporation chamber absorbs the heat transferred from the evaporator cover through contact and heats up, reaching its boiling point and undergoing boiling heat transfer. The evaporator has an inlet and an outlet. The inlet is for liquid inlet and is connected to the liquid inlet pipe using a smaller diameter connector. The outlet is a gas-liquid mixing channel and is connected to the liquid outlet pipe using a larger diameter connector. The evaporators are symmetrically arranged and connected to the secondary liquid supply line via a Y-shaped liquid supply pipe formed by a three-way fitting. An external heat dissipation fin 16 may be provided on one side of the evaporator. The evaporator cover is connected to the base by six spring-loaded screws arranged symmetrically in pairs on both sides or four locking blocks with buckles arranged symmetrically in pairs on both sides; the base is provided with symmetrical locking plates 14 on both sides, and the two ends of the locking plates are provided with upward protruding and oppositely arranged hooks; the top of the cover is provided with positioning screws 15 that extend out and are equidistantly arranged, and the bottom of the component to be cooled is inserted into the positioning screws.

[0030] The evaporator base described above is equipped with capillary structures and / or dense fins. These capillary structures and / or dense fins are disposed within a sheet metal stamped flow channel structure within the base. The dense fins are sheet metal stamped inner fin assemblies. The heat source is attached to both sides of the corresponding sheet metal stamped flow channel structure. Specifically, the evaporator has the following two embodiments: Embodiment 1: The evaporator base is composed of a sheet metal stamped flow channel structure, an inlet pipe, and an outlet pipe. The heat source is attached to both sides of the corresponding sheet metal stamped flow channel structure (upper and lower dual heat sources). Liquid enters the closed cavity formed by the corresponding sheet metal stamped flow channel structure through the inlet pipe and flows out through the outlet pipe, carrying away the liquid that has passed through the heat source and been heated, thus achieving heat dissipation. In Example 2, the evaporator base is equipped with sheet metal stamped flow channel structure, sheet metal stamped inner fin assembly, liquid inlet pipe, liquid outlet pipe, etc. The liquid from both sides (upper and lower dual heat sources) of the heat source is in contact with the corresponding sheet metal stamped flow channel structure. The liquid enters the closed cavity formed by the corresponding sheet metal stamped flow channel structure through the liquid inlet pipe and flows out through the liquid outlet pipe, carrying away the liquid that has been heated by the heat source to achieve the purpose of heat dissipation.

[0031] Meanwhile, the aforementioned phase change liquid cooling medium includes a low-boiling-point working fluid, which includes a dielectric fluid; the liquid supply pipe and corresponding pipelines adopt flexible pipes; the phase change heat exchange unit mainly adopts plate heat exchange, and a pump for the phase change working fluid is provided in the phase change heat exchange unit.

[0032] This structure involves heat transfer through contact between the evaporator end (cold plate) of the evaporator and the components to be cooled (such as CPU boards, GPU boards, memory, hard drives, etc.). Therefore, during the operation of the components to be cooled, the heat generated by them is directly absorbed by the phase change working fluid in the cooling chamber of the evaporator end. After absorbing heat, the phase change working fluid's temperature rises, and it changes from liquid to vapor. The phase change working fluid is driven by a pump and flows through a circulation loop consisting of the evaporator end, secondary side liquid supply pipeline, secondary liquid distribution unit, and phase change heat exchange unit (CDU). The vapor is carried into the phase change heat exchange unit, cooled, and becomes a lower temperature liquid. It then flows back to the evaporator end through the output pipeline to absorb the heat generated by the components to be cooled again. This cycle carries away the heat from the components to be cooled, thus achieving heat dissipation of the secondary side heat exchange unit. Simultaneously, in the primary heat exchange unit, heat exchange occurs through a phase change heat exchange unit (CDU). The CDU forms a loop with the cooling tower via the primary liquid supply pipeline, transferring the heat from the secondary heat exchange unit to the cooling tower for cooling and dissipating the heat into the atmosphere. Because this process does not require high-efficiency components such as compressors and fans, the overall system PUE value is reduced to below 1.2, meeting the current industry and national government planning and requirements for PUE. Simultaneously, the evaporation end of the secondary heat exchange unit and the CDU are dominated by phase change heat exchange, and their heat exchange efficiency is much higher than that of air-cooled and liquid-cooled heat exchange, with a heat transfer coefficient difference of 1-3 orders of magnitude. This improves heat dissipation performance while meeting the current and future needs of increasing chip heat flux density.

[0033] In summary, this structure includes a pump-driven phase-change liquid cooling system and a server, relating to the field of server technology, and is a pump-driven two-phase cooling system. The above description is intended to illustrate the technical means of this utility model and is not intended to limit its scope. Any obvious improvements or substitutions made to this utility model by those skilled in the art based on existing common knowledge also fall within the protection scope of the claims of this utility model.

Claims

1. A pump-driven phase change liquid cooling structure, wherein a liquid distribution unit (4) is provided on one side of the cabinet door frame of the cabinet (1) of the structure, and the quick connector of the liquid distribution unit is connected to the liquid-cooled server node (2) in the cabinet through a pipeline and a secondary side liquid supply pipeline (3), and the liquid supply pipeline of the secondary side liquid supply pipeline on one side of the liquid-cooled server node is provided with a ball valve regulating pipeline, and the cabinet of the liquid-cooled server node, which is pushed into the cabinet one by one, is respectively set between the two side frames of the cabinet through the slide rail assembly on both sides of the outer diameter of the cabinet; characterized in that The structure is divided into a primary heat exchange unit (7) and a secondary heat exchange unit (8). The primary heat exchange unit and the secondary heat exchange unit are two interconnected and relatively independent circulation systems. The phase change heat exchange unit (5) serves as a bridge to connect the primary heat exchange unit and the secondary heat exchange unit for heat exchange. The secondary heat exchange unit includes a component to be cooled, an evaporator (9), a secondary liquid supply pipeline (3), a liquid distribution unit (4), a phase change heat exchange unit, and a pump for the phase change working fluid, forming an indoor circulation loop. The component to be cooled inside the liquid-cooled server node is in close contact with the evaporator for heat transfer, completing the heat output and exchange work from the secondary heat exchange unit to the primary heat exchange unit. The primary heat exchange unit includes an outdoor cooling tower (6), a primary liquid supply pipeline, and a phase change heat exchange unit, forming an outdoor circulation loop to dissipate the heat exchanged by the secondary heat exchange unit to the atmosphere. The phase change heat exchange unit and the liquid distribution unit are connected by pipelines, and the phase change heat exchange unit and the outdoor cooling tower are connected by water pipes.

2. The pump-driven phase change liquid cooling structure according to claim 1, characterized in that... The base (13) of the evaporator (9) and the cover (12) on the base are sealed together to form an evaporation chamber. The liquid inlet pipe (10) and the liquid outlet pipe (11) are connected by connectors of different diameters to form a liquid inlet and liquid outlet structure. The evaporation chamber is filled with phase change liquid, which is a phase change liquid cooling medium. The heat transfer component is brought into contact with the evaporator cover for heat transfer. The phase change liquid in the evaporation chamber absorbs the heat from the evaporator cover through contact heat transfer and rises in temperature. After reaching the boiling point, boiling heat transfer occurs.

3. The pump-driven phase change liquid cooling structure according to claim 2, characterized in that... The evaporator (9) has a capillary structure and / or dense fins in its base (13).

4. The pump-driven phase change liquid cooling structure according to claim 3, characterized in that... The capillary structure and / or dense fins in the base (13) of the evaporator (9) are provided in the sheet metal stamping flow channel structure in the base (13). The dense fins are sheet metal stamping inner fin assemblies, and the heat source is attached to both sides of the corresponding sheet metal stamping flow channel structure.

5. The pump-driven phase change liquid cooling structure according to claim 2, characterized in that... The evaporator (9) is provided with an inlet and an outlet. The inlet is used for liquid inlet and is connected to the liquid inlet pipe (10) with a connector of smaller diameter. The outlet is a gas-liquid mixing channel and is connected to the liquid outlet pipe (11) with a connector of larger diameter.

6. The pump-driven phase change liquid cooling structure according to claim 2, characterized in that... The evaporator (9) is symmetrically arranged and connected to the secondary side liquid supply pipeline (3) through a Y-shaped liquid supply pipe formed by a three-way fitting. An external heat dissipation fin (16) may be provided on one side of the evaporator.

7. The pump-driven phase change liquid cooling structure according to claim 2, characterized in that... The cover (12) of the evaporator (9) is connected to the base (13) by six spring-loaded screws arranged symmetrically in pairs on both sides or four locking blocks with buckles arranged symmetrically in pairs on both sides. The top of the locking block has a protruding screw post in the middle. The retaining spring at one end of the buckle is fitted into the screw post and the other end is hinged and fixed to one side of the locking block below the screw post. The hinge of the retaining spring extends and protrudes from the hinge hole on the other side, bending in an L-shape and protruding above the groove at the cover. The base has symmetrically arranged retaining plates (14) on both sides. The two ends of the retaining plates have upward protruding hooks arranged opposite each other. The top of the cover has equidistant positioning screws (15) that protrude and are arranged at equal intervals. The bottom of the heat dissipation component is inserted into the positioning screw.

8. The pump-driven phase change liquid cooling structure according to claim 2, characterized in that... The phase change liquid cooling medium includes a low-boiling-point working fluid, which includes a dielectric fluid.

9. The pump-driven phase change liquid cooling structure according to claim 1, characterized in that... The liquid supply pipe and corresponding pipelines are made of flexible pipe.

10. The pump-driven phase change liquid cooling structure according to claim 1, characterized in that... The phase change heat exchange unit (5) is mainly plate heat exchanged, and a pump for phase change working fluid is provided in the phase change heat exchange unit.

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