A pump-free electromagnetic driving liquid metal heat exchange enhanced server liquid cooling system

Abstract

The application discloses a pump-free electromagnetic drive liquid metal heat exchange enhanced server liquid cooling system, which is filled with liquid metal in a closed circulation loop, and the circulation loop is provided with at least one cold plate assembly for absorbing the heat of a chip, at least one heat dissipation cold row and a connecting pipeline, at least one electromagnetic drive unit is arranged, the electromagnetic drive unit comprises at least one pair of pipeline electromagnets integrated on the outer wall of the pipeline of the circulation loop, is used for generating Lorentz force along the main flow direction in the electrified liquid metal to drive the circulation of the liquid metal, and at least one longitudinal heat exchange enhancement unit is arranged, which is used for longitudinally disturbing the liquid metal flowing in the cold plate assembly, and improving the heat exchange between the liquid metal and the cold plate assembly. The system cancels the independent pump body, the electromagnetic drive unit is directly integrated on the pipeline, the structure is highly integrated, there is no vibration, noise and mechanical wear, and the problems of pump body leakage and extra space occupation are fundamentally solved.

Description

Technical Field

[0001] This invention relates to the field of server liquid cooling technology, and in particular to a pumpless electromagnetically driven liquid metal heat exchange enhanced server liquid cooling system. Background Technology

[0002] With the increasing computing power density of data centers, the heat flux density of a single chip has exceeded hundreds of watts per square centimeter. Using liquid metal as a coolant can significantly reduce thermal resistance. However, existing liquid metal cooling systems generally rely on mechanical pumps or independent electromagnetic pumps to drive the coolant circulation. Mechanical pumps suffer from vibration, noise, and wear issues, while independent electromagnetic pumps, although eliminating moving parts, still exist as independent pump bodies, increasing system size and potential leakage points. Furthermore, the pump body itself lacks local control over the flow of liquid metal.

[0003] On the other hand, in the high heat flux density region directly above the chip, liquid metal often flows horizontally across the heat transfer surface in a laminar state, resulting in a thick thermal laminar boundary layer that limits the local heat transfer coefficient. Existing solutions struggle to flexibly enhance the longitudinal heat transfer capacity of specific regions without altering the overall flow channel structure, easily leading to the formation of localized hotspots.

[0004] For example, invention application No. 202411876586.8 discloses a liquid metal-cooled server and its application method. In this application, the processor cooling component and memory cooling component are connected via a liquid metal circulation pipeline to utilize liquid metal for circulating cooling. The circulation power of the liquid metal in the circulation pipeline comes from an electromagnetic pump. This solution improves the server's heat dissipation performance, but it also requires an additional electromagnetic pump device to provide power for the liquid metal circulation.

[0005] For example, invention application No. 202310520316.2 discloses a liquid metal heat dissipation device, belonging to the technical field of heat dissipation devices. This application's solution includes a liquid flow pipe and an electromagnetic pump. The liquid flow pipe and the electromagnetic pump are connected to form a closed loop, enhancing the heat transfer effect between the liquid metal and the pipe wall, thus improving heat exchange efficiency. However, this solution also suffers from the following drawback: it still relies on the electromagnetic pump structure for power, which not only increases the overall size and complexity of the system but also introduces additional pump operating noise.

[0006] Therefore, it is necessary to provide a liquid metal heat dissipation system that does not require an independent pump body and can actively enhance longitudinal heat exchange for the chip. Summary of the Invention

[0007] To address the aforementioned problems, the present invention aims to provide a pumpless electromagnetically driven liquid metal heat exchange enhanced server liquid cooling system, which solves the problem that the existing technology relies on additional configuration of electromagnetic pumps to provide liquid metal circulation power, resulting in an increase in the overall system size, structural complexity, and the introduction of additional operating noise.

[0008] The objective of this invention can be achieved through the following technical solution: a pump-free electromagnetically driven liquid metal heat exchange enhanced server liquid cooling system, comprising:

[0009] A closed liquid metal circulation loop, the circulation loop being filled with liquid metal, the circulation loop being provided with at least one cold plate assembly for absorbing chip heat, at least one heat dissipation radiator, and connecting pipes;

[0010] At least one electromagnetic drive unit includes at least a pair of pipe electromagnets integrated into the outer wall of the pipe in the circulation loop for generating a Lorentz force in the energized liquid metal along the main flow direction to drive the circulation of the liquid metal.

[0011] As a further aspect of the present invention, it also includes:

[0012] At least one longitudinal heat exchange enhancement unit is used to longitudinally disturb the liquid metal flowing inside the cold plate assembly, thereby improving the heat exchange between the liquid metal and the cold plate assembly.

[0013] As a further embodiment of the present invention, the cold plate assembly includes a lower cold plate and an upper shell. An impact cavity is formed inside the lower cold plate and the upper shell. The impact cavity is divided into multiple flat flow channels by a flow channel plate. After the liquid metal enters along the inlet of the impact cavity, it is guided by the flat flow channels and then flows out along the outlet of the impact cavity.

[0014] As a further embodiment of the present invention, the longitudinal heat transfer enhancement unit includes:

[0015] A pair of cold plate electromagnets located above and below the cold plate assembly, the magnetic field generated by the cold plate electromagnets causing the liquid metal to be subjected to a Lorentz force perpendicular to the lower cold plate.

[0016] As a further embodiment of the present invention, the longitudinal heat transfer enhancement unit further includes:

[0017] The paired auxiliary electrodes located on opposite sides of the sidewall of the impact chamber provide transverse current, which is perpendicular to the longitudinal magnetic field component.

[0018] As a further embodiment of the present invention, a temperature sensor is provided on the inner side of the impact cavity to monitor the real-time temperature of the liquid metal in the impact cavity, and the controller of the cold plate electromagnet adjusts the magnetic field strength of the cold plate electromagnet according to the temperature sensor signal.

[0019] As a further embodiment of the present invention, the cold plate electromagnet is connected to direct current, which causes the cold plate electromagnet to generate a unidirectional longitudinal magnetic field, causing the liquid metal in the impact cavity to be subjected to Lorentz force and pushed towards the heat-absorbing surface of the cold plate, forming a vertical impact jet, which destroys the laminar boundary layer near the heat-absorbing surface.

[0020] As a further embodiment of the present invention, the cold plate electromagnet is connected to alternating current, so that the liquid metal in the impact cavity is subjected to alternating Lorentz force to induce eddy currents, forming a multi-directional stirring force throughout the impact cavity.

[0021] As a further embodiment of the present invention, the liquid metal is a gallium-based alloy.

[0022] As a further embodiment of the present invention, the number of the pipeline electromagnets is at least two pairs, which are respectively arranged in different pipeline sections of the circulation loop.

[0023] The beneficial effects of this invention are:

[0024] 1. The system of this invention completely eliminates the independent pump body. The electromagnetic drive unit is directly integrated into the pipeline or cold plate wall. The structure is highly integrated, with no vibration, no noise, and no mechanical wear, fundamentally eliminating the problems of pump body leakage and occupying extra space.

[0025] 2. The present invention proposes to set up a dedicated longitudinal magnetic field generating device in the area directly opposite the chip. By actively controlling the longitudinal movement of liquid metal, the thermal laminar flow boundary layer is effectively thinned or destroyed, the local heat transfer coefficient is greatly improved, and the local hot spot problem of high heat flux density chips is solved.

[0026] 3. The longitudinal heat exchange enhancement unit of the present invention can be adjusted in real time according to the chip temperature without increasing the overall system flow rate, thus saving energy and responding quickly.

[0027] 4. Compared with existing liquid metal heat dissipation solutions that use independent electromagnetic pumps or uniform parallel flow, this invention differs in its driving principle and local enhancement principle. It features innovative structural layout, smaller overall space occupation, higher heat exchange efficiency, and can be adapted to the compact installation space inside servers. Attached Figure Description

[0028] Figure 1 This is a schematic diagram of the server liquid cooling system of the present invention;

[0029] Figure 2 This is a schematic diagram of the separate installation of the cold plate assembly and the longitudinal heat exchange enhancement unit of the present invention;

[0030] Figure 3 This is a schematic diagram of the split structure of the cold plate assembly of the present invention;

[0031] Figure 4This is a schematic diagram of the split structure of the longitudinal heat transfer enhancement unit of the present invention;

[0032] Figure 5 This is a schematic diagram of the installation of the electromagnetic drive unit of the present invention;

[0033] Figure 6 This is a schematic diagram of the installation of the dual-channel electromagnetic drive unit of the present invention.

[0034] A. Chip;

[0035] 100. Metal loop circuit;

[0036] 200. Cold plate assembly; 210. Lower cold plate; 220. Upper shell; 230. Impact cavity; 240. Flow channel plate;

[0037] 300. Heat dissipation radiator;

[0038] 400. Piping; 410. Adapter valve;

[0039] 500. Electromagnetic drive unit; 510. Pipeline electromagnet; 520. Power supply module;

[0040] 600, Longitudinal heat exchange enhancement unit; 610, Cold plate electromagnet; 620, Auxiliary electrode; 630, Temperature sensor. Detailed Implementation

[0041] Embodiments of the present invention are described in detail below. Examples of these embodiments are illustrated in the accompanying drawings, wherein the same or similar symbols denote the same or similar elements or elements having the same or similar functions throughout. The embodiments described below with reference to the accompanying drawings are exemplary and are only used to explain the present invention, and should not be construed as limiting the present invention.

[0042] Example 1:

[0043] like Figure 1 As shown, the present invention discloses a pumpless electromagnetically driven liquid metal server liquid cooling system, comprising:

[0044] A closed liquid metal circulation loop 100 includes at least one cold plate assembly 200 for absorbing heat from chip A, at least one heat dissipation radiator 300, and connecting pipes 400.

[0045] The liquid metal circulation loop 100 is filled with liquid metal, preferably a gallium indium tin alloy. This alloy has a melting point below room temperature, strong conductivity, good fluidity, and can meet the long-term stable operation requirements of the server's sealed heat dissipation.

[0046] The cold plate assembly 200 is located above chip A and in contact with chip A, and is used to exchange heat with chip A and absorb the heat generated by chip A during operation.

[0047] The radiator 300 is connected to an external CDU (Coolant Distribution Unit) or fan cooling system to dissipate the heat from the liquid metal circulation loop 100 to the external environment of the server.

[0048] The connecting pipe 400 connects the inlet and outlet of the impact chamber 230 of the cold plate assembly 200, as well as the outlet and inlet of the heat dissipation radiator 300, so that the liquid metal forms a circulation path in a closed loop.

[0049] Specifically, such as Figure 2 and Figure 3 As shown, the cold plate assembly 200 includes a lower cold plate 210 and an upper housing 220. The upper housing 220 is connected to the upper surface of the lower cold plate 210. An impact cavity 230 is formed inside the lower cold plate 210 and the upper housing 220. A plurality of parallel flow channel plates 240 are connected to the upper surface of the lower cold plate 210. The flow channel plates 240 divide the interior of the impact cavity 230 into a plurality of parallel flat flow channels. After the liquid metal enters along the inlet of the impact cavity 230, it is first diverted by the flat flow channel on the inlet side and flows along the parallel flat flow channels over the upper surface of the lower cold plate 210. It fully exchanges heat with the lower cold plate 210, which has absorbed the heat of chip A. After the liquid metal is heated, it converges in the flat flow channel on the outlet side of the impact cavity 230 and is transported to the heat dissipation radiator 300 through the connecting pipe 400 to complete the cooling. The cooled liquid metal then flows back to the impact cavity 230 of the cold plate assembly 200, thereby continuously removing the heat generated by chip A during operation.

[0050] like Figure 5 As shown, at least one pair of pipe electromagnets 510 on the outer wall of the pipe 400 of the circulation loop form an electromagnetic drive unit 500 for generating a Lorentz force along the main flow direction in the energized liquid metal to drive the circulation of the liquid metal.

[0051] like Figure 5As shown, the pipeline electromagnet 510 includes an N-pole electromagnet and an S-pole electromagnet, which are placed on both sides of the pipeline 400 and are connected to an external power source. After being energized, a magnetic field perpendicular to the axis of the pipeline 400 is formed inside the pipeline 400. At the same time, the pipeline 400 is equipped with a transfer valve 410, which connects the liquid metal to the power module 520. The current of the liquid metal is along the axis of the pipeline 400. The charged liquid metal is subjected to a Lorentz force in the magnetic field. The direction of the force is consistent with the direction of the circulation flow of the liquid metal, thereby directly driving the liquid metal to flow in the loop. There is no need to set up an additional mechanical pump, which not only eliminates the noise and vibration problems caused by the operation of mechanical pumps, but also reduces the risk of system seal failure, and improves the reliability and stability of the liquid cooling system.

[0052] Furthermore, a longitudinal heat exchange enhancement unit 600 is provided around the cold plate assembly 200 to longitudinally disturb the liquid metal flowing inside the cold plate assembly 200 (longitudinal refers to the direction perpendicular to the lower cold plate 210) and improve the heat exchange between the liquid metal and the cold plate assembly 200.

[0053] Specifically, such as Figure 4 As shown, the longitudinal heat exchange enhancement unit 600 includes: an N-pole electromagnet or an S-pole electromagnet located above and below the cold plate assembly 200. The N-pole electromagnet and the S-pole electromagnet together form a pair of cold plate electromagnets 610. They are connected to an external power source. When powered on, the magnetic field generated by the cold plate electromagnets 610 causes the liquid metal to be subjected to a Lorentz force perpendicular to the lower cold plate 210. This creates a longitudinal force disturbance on the liquid metal that originally flowed horizontally in the cold plate flow channel, causing the liquid metal to move longitudinally while flowing. This breaks the laminar boundary layer formed by the liquid metal in the flow channel, enhances the contact between the liquid metal and the heat exchange surface of the cold plate in the near-wall area of ​​the flow channel, and improves the heat exchange performance.

[0054] Furthermore, such as Figure 4 As shown, a temperature sensor 630 is provided on the inner side of the impact cavity 230 to monitor the real-time temperature of the liquid metal in the impact cavity 230; the controller of the cold plate electromagnet 610 adjusts the current intensity of the cold plate electromagnet 610 according to the signal of the temperature sensor 630.

[0055] Example 2:

[0056] Based on Example 1, in this embodiment, the cold plate electromagnet 610 is connected to a direct current, which causes the cold plate electromagnet 610 to generate a unidirectional longitudinal magnetic field. This causes the liquid metal in the impact cavity 230 to be subjected to Lorentz force and pushed towards the cold plate heat-absorbing surface, forming a vertical impact jet that destroys the laminar boundary layer near the heat-absorbing surface.

[0057] After the liquid metal fluid impacts the heat-absorbing surface, it disperses in all directions, converges, and flows out through the outlet of the impact chamber 230, entering the downstream flow channel. This localized longitudinal jet only occurs in the hot zone of chip A and does not significantly increase the overall flow resistance of the system.

[0058] Furthermore, such as Figure 4 As shown, a pair of auxiliary electrodes 620 are provided on opposite sides of the sidewall of the impact chamber 230. The pair of auxiliary electrodes 620 are connected to an external power source to provide a transverse current, the direction of which is perpendicular to the longitudinal magnetic field component. This causes the liquid metal to be subjected to a Lorentz force in the vertical direction, which continuously impacts the heat exchange surface of the cold plate, further enhancing the longitudinal disturbance heat absorption effect.

[0059] Furthermore, the cold plate is made of a high thermal conductivity metal. When the temperature of chip A rises, the controller of the cold plate electromagnet 610 controls the power supply to the cold plate electromagnet 610 and the paired auxiliary electrodes 620 according to the signal from the temperature sensor 630. The cold plate electromagnet 610 is automatically controlled, and the heat exchange intensity can be automatically adjusted according to the temperature inside the impact cavity 230, which reduces the overall energy consumption of the system and can accurately solve the problem of local overheating of the chip.

[0060] Example 3:

[0061] Based on Example 1, in this embodiment, the cold plate electromagnet 610 is connected to AC power, so that the liquid metal in the impact cavity 230 is subjected to alternating Lorentz force to induce eddy currents, forming a multi-directional stirring force throughout the impact cavity 230.

[0062] The cold plate electromagnet 610 uses an AC coil, which generates an alternating magnetic field within the impact cavity 230 when AC current is applied. The alternating magnetic field induces eddy currents in the liquid metal, forming a chaotic multi-directional stirring force throughout the impact cavity 230. This causes the liquid metal to undergo irregular and intense mixing in both the longitudinal and transverse directions, thus achieving highly efficient longitudinal heat transfer enhancement without the need for paired auxiliary electrodes 620.

[0063] Example 4:

[0064] Based on Example 1, this embodiment has at least two pairs of pipeline electromagnets 510, which are respectively arranged in different pipeline 400 segments of the metal circulation loop 100.

[0065] like Figure 6As shown, a pair of pipe electromagnets 510 are located between the outlet of the heat dissipation radiator 300 and the inlet of the cold plate assembly 200 in the pipe 400. Another pair of pipe electromagnets 510 are arranged between the outlet of the cold plate assembly 200 and the inlet of the heat dissipation radiator 300 in the pipe 400. The Lorentz forces generated by the two pairs of pipe electromagnets 510 work in the same direction to drive the liquid metal to continuously circulate along a predetermined loop. The flow rate of the liquid metal can be flexibly controlled by adjusting the energizing frequency and current, adapting to the different heat dissipation power requirements of chip A. Without the need for additional mechanical pumps, the liquid metal can be autonomously circulated in the entire cooling circuit. At the same time, the vibration and sealing leakage risks caused by mechanical pumps are eliminated, improving the stability and reliability of system operation.

[0066] The above description is only a preferred embodiment of the present invention, but the scope of protection of the present invention is not limited thereto. Any equivalent substitutions or modifications made by those skilled in the art within the scope of the technology disclosed in the present invention, based on the technical solution and inventive concept of the present invention, should be covered within the scope of protection of the present invention.

[0067] In this invention, unless otherwise explicitly specified and limited, "above" or "below" the second feature can mean that the first feature is in direct contact with the second feature, or that the first feature is in indirect contact with the second feature through an intermediate medium. Furthermore, "above," "over," and "on top" of the second feature can mean that the first feature is directly above or diagonally above the second feature, or simply that the first feature is at a higher horizontal level than the second feature. "Below," "below," and "under" the second feature can mean that the first feature is directly below or diagonally below the second feature, or simply that the first feature is at a lower horizontal level than the second feature.

Claims

1. A pump-free electromagnetically driven liquid metal heat exchange enhanced server liquid cooling system, characterized in that, include: A closed liquid metal circulation loop, the circulation loop being filled with liquid metal, the circulation loop being provided with at least one cold plate assembly for absorbing chip heat, at least one heat dissipation radiator, and connecting pipes; At least one electromagnetic drive unit includes at least a pair of pipe electromagnets integrated into the outer wall of the pipe in the circulation loop for generating a Lorentz force in the energized liquid metal along the main flow direction to drive the circulation of the liquid metal.

2. The system according to claim 1, characterized in that, Also includes: At least one longitudinal heat exchange enhancement unit is used to longitudinally disturb the liquid metal flowing inside the cold plate assembly, thereby improving the heat exchange between the liquid metal and the cold plate assembly.

3. The system according to claim 2, characterized in that, The cold plate assembly includes a lower cold plate and an upper shell. An impact cavity is formed inside the lower cold plate and the upper shell. The impact cavity is divided into multiple flat channels by a flow channel plate. The liquid metal enters along the inlet of the impact cavity, is guided by the flat channels, and then flows out along the outlet of the impact cavity.

4. The system according to claim 2, characterized in that, The longitudinal heat exchange enhancement unit includes a pair of cold plate electromagnets located above and below the cold plate assembly. The magnetic field generated by the cold plate electromagnets causes the liquid metal to be subjected to a Lorentz force perpendicular to the lower cold plate.

5. The system according to claim 4, characterized in that, The longitudinal heat exchange enhancement unit further includes a pair of auxiliary electrodes located on opposite sides of the sidewall of the impact cavity, used to provide transverse current, the direction of which is perpendicular to the longitudinal magnetic field component.

6. The system according to claim 5, characterized in that, A temperature sensor is installed on the inner side of the impact chamber to monitor the real-time temperature of the liquid metal inside the impact chamber. The controller of the cold plate electromagnet adjusts the magnetic field strength of the cold plate electromagnet according to the temperature sensor signal.

7. The system according to claim 5, characterized in that, The cold plate electromagnet is connected to direct current, which causes the cold plate electromagnet to generate a unidirectional longitudinal magnetic field. This causes the liquid metal in the impact cavity to be pushed towards the heat-absorbing surface of the cold plate by the Lorentz force, forming a vertical impact jet that destroys the laminar boundary layer near the heat-absorbing surface.

8. The system according to claim 4, characterized in that, The cold plate electromagnet is connected to alternating current, causing the liquid metal in the impact cavity to be induced by alternating Lorentz force to generate eddy currents, forming a multi-directional stirring force throughout the impact cavity.

9. The system according to claim 1, characterized in that, The liquid metal is a gallium-based alloy.

10. The system according to claim 1, characterized in that, The number of pipeline electromagnets is at least two pairs, which are respectively arranged in different pipeline sections of the circulation loop.

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