A locally enhanced server chip phase change liquid cooling method

Abstract

The application discloses a kind of local enhanced server chip phase change liquid cooling method, chip board is soaked in two-phase cooling fluid by being arranged horizontally, rely on the gasification of two-phase cooling fluid to chip board cooling, after the gasification of two-phase cooling fluid, reach the upper end of two-phase cooling fluid chamber and cooling device heat liquefaction and fall back below, its characterized in that, in the upper space position of the high heat area of chip board, two-phase cooling fluid is guided to flow upwards, so that the bubble generated on the surface of high heat area can be accelerated to reach the upper end of two-phase cooling fluid chamber and be liquefied.The application can better aim at the cooling treatment of high heat area of chip, to balance overall cooling effect, improve the server whole machine performance.

Description

Technical Field

[0001] This invention relates to the field of data center server cooling technology, and more specifically to a locally enhanced phase change liquid cooling method for server chips. Background Technology

[0002] With the continuous improvement of the performance of modern electronic devices, especially in the field of high-power chips, the power consumption and heat generation of chips are also increasing. These high-power chips are widely used in computer servers, data centers, artificial intelligence, 5G communications, and high-performance computing. Traditional air cooling technology has significant shortcomings in cooling high-power chips due to its efficiency limitations. Especially with the increasing power density of processors and the growing demand for heat dissipation, traditional heat dissipation methods are struggling to meet the increasingly stringent heat dissipation requirements.

[0003] Liquid cooling technology, as a relatively effective cooling method, has been widely used in recent years. With advancements in cooling technology, liquid cooling systems have evolved from single-phase to two-phase liquid cooling. Single-phase liquid cooling primarily relies on the thermal conductivity of the liquid to remove heat from the chip surface. Although its cooling effect is improved compared to air cooling, its heat dissipation efficiency remains limited when dealing with ultra-high power density chips. In contrast, two-phase liquid cooling technology, through the evaporation and condensation processes of the liquid, can provide higher heat transfer efficiency, making it particularly suitable for cooling high-power chips.

[0004] Two-phase liquid cooling, also known as immersion two-phase liquid cooling technology, typically involves immersing the entire circuit board in a liquid phase change material (PCM) chamber. The PCM liquid's evaporation-condensation process effectively removes heat from the chip. After evaporating into a gas, the PCM rises to the top of the chamber, exchanges heat with a cooling device located at the top, and then liquefies again, dripping back down. The cooling device then transfers the heat to the outside through a heat exchange system. This cooling method not only achieves more efficient heat exchange but also significantly reduces system temperature fluctuations due to the thermal conductivity and surface tension of the liquid, improving component stability and lifespan. Furthermore, two-phase immersion liquid cooling has lower noise and energy consumption, effectively reducing noise pollution caused by high-speed fans and high-power blowers in air-cooled systems.

[0005] However, despite the significant advantages of two-phase immersion liquid cooling technology, it still faces many challenges and has much room for engineering optimization in practical applications.

[0006] First, different areas on the chip board generate different amounts of heat due to their different functions, but the cooling methods are the same for all areas, leading to a mismatch between cooling effectiveness and heat generation. For example, high-power computing areas on the chip board often generate a lot of heat, while low-power components such as memory and hard drives generate less heat. In such cases, if the computing areas are not cooled in time, it will greatly reduce computing efficiency.

[0007] Secondly, high-heat areas on the chip board lead to accelerated vaporization rates. After the coolant vaporizes, it easily forms a layer of bubbles on the surface of these areas. If these bubbles are not removed promptly and effectively, they can even form a localized "gas film." Because gases have poor thermal conductivity, the bubbles adhering to the surface of these high-heat areas form a heat-insulating layer, reducing the heat exchange efficiency between the phase change liquid and the chip surface. This creates a vicious cycle, causing the high-heat areas to overheat even more severely, ultimately affecting the stability of the entire server system.

[0008] Therefore, how to obtain a two-phase immersion liquid cooling method for servers that has better cooling effect, can specifically address uneven heating, and improve the overall computing power of servers has become a problem that needs to be further considered and solved by those skilled in the art. Summary of the Invention

[0009] In view of the shortcomings of the prior art, the technical problem to be solved by the present invention is: how to provide a server chip phase change liquid cooling method that can better treat the high heat generation area of ​​the chip, so as to balance the cooling effect and improve the local enhancement of the overall performance of the server.

[0010] To solve the above-mentioned technical problems, the present invention adopts the following technical solution:

[0011] A locally enhanced phase change liquid cooling method for server chips involves immersing a horizontally positioned chip board in a two-phase coolant. The chip board is cooled by the vaporization of the two-phase coolant. After vaporization, the two-phase coolant rises to the upper end of the two-phase coolant chamber, exchanges heat with the cooling device, liquefies, and falls back down. The key feature is that the two-phase coolant is guided to flow upward in the upper space of the high-heat area of ​​the chip board, so that the bubbles generated on the surface of the high-heat area can reach the upper end of the two-phase coolant chamber more quickly and liquefy.

[0012] In this way, this solution can divert the upper space of the high-heat area of ​​the chip board upwards separately, so that the generated bubbles can reach the upper end of the two-phase coolant chamber for liquefaction more quickly, while the surrounding liquid flows in from below to replenish it. This not only makes the cooling effect of the high-heat area better, but also improves the heat dissipation efficiency and heat dissipation uniformity of other areas due to the increased fluidity of the coolant.

[0013] Furthermore, the high-heat area is the region where the CPU is located. This allows for more targeted heat dissipation and cooling of the computing area, ensuring stable server computing performance.

[0014] Furthermore, when the surface temperature of the high-heat-generating area exceeds the vaporization temperature of the two-phase coolant and reaches a preset temperature, the bubbles generated on the surface are driven away and enter the two-phase coolant liquid. This can further improve the heat dissipation and cooling effect on the high-heat-generating area.

[0015] Furthermore, this method relies on a server chip phase change liquid cooling system, which includes a cooling chamber, a horizontally arranged chip plate at the bottom of the cooling chamber, a phase change coolant immersed in the middle, a cooling plate at the top, and a cooling device inside the cooling plate. A flow guide is provided above the high heat generation area of ​​the chip plate, and an upward-facing fan blade device is provided inside the flow guide.

[0016] In this way, the fan blade device can guide the phase change coolant in the high-heat-generating area of ​​the chip board upwards along the guide shroud, thus more quickly moving the vaporized bubbles in the high-heat-generating area upwards and improving the phase change heat transfer efficiency of the high-heat-generating area. At the same time, the coolant flows from four directions below the guide shroud to replenish the high-heat-generating area, which can also better improve the heat exchange effect on the chip board.

[0017] Furthermore, a thermoelectric power generation chip is provided on the lower surface of the cooling plate corresponding to the upper port of the air guide shroud, and the positive and negative output terminals of the thermoelectric power generation chip are connected to the fan blade device as power sources.

[0018] The high-heat bubbles generated in the high-heat area rise to the thermoelectric chip, raising the temperature of its lower surface and creating a significant temperature difference with its upper surface. The resulting electricity powers the fan blades. The higher the heat generated in the high-heat area of ​​the chip, the faster the bubbles rise, the higher the temperature at the bottom of the thermoelectric chip, and the greater the temperature difference, the greater the power generation. This corresponds to a faster fan blade rotation, accelerating bubble rise and improving heat exchange efficiency in the high-heat area. Therefore, it achieves an adaptive heat exchange and cooling effect.

[0019] Furthermore, the lower surface of the cooling plate has a downward protrusion corresponding to the upper port of the flow guide. The lower protrusion is made of thermally conductive material. The thermoelectric power generation chip is installed on the lower surface of the lower protrusion. The lower surface of the lower protrusion also has a downward flange around its perimeter, forming a groove structure inside.

[0020] In this way, the lower surface of the protrusion can be immersed in the phase change coolant. The bubbles that rise upward through the guide shroud are concentrated into the sink, heating and reliquefying the lower surface of the thermoelectric chip. This prevents the bubbles in the guide shroud from entering the gas phase layer at the top of the phase change coolant and diffusing, which would result in uneven heating of the lower surface of the thermoelectric chip.

[0021] Furthermore, the vertical cross-section of the flow guide is generally truncated cone-shaped, with a larger bottom and a smaller top.

[0022] This allows the bubbles generated in the high-heat area to concentrate and enter the sink on the lower surface of the convex part, thus better heating the thermoelectric chip.

[0023] Furthermore, the flow guide is a mesh structure.

[0024] Furthermore, the upper surface of the high-heat area of ​​the chip board has upwardly positioned heat dissipation protrusions, which are made of porous thermally conductive material.

[0025] This allows for a greater increase in the contact area between the high-heat-generating areas of the chip board and the phase change coolant, thereby improving heat exchange efficiency.

[0026] Furthermore, the internal aperture of the heat dissipation protrusion gradually increases from bottom to top.

[0027] In this way, the air bubbles inside the heat dissipation protrusion gradually increase in size from bottom to top and then detach from the protrusion and rise upwards.

[0028] Furthermore, the upper surface of the heat dissipation protrusion is provided with multiple rows of vertical grooves, and each vertical groove is provided with a shape memory alloy metal strip. One end of the shape memory alloy metal strip is fixed in the vertical groove, and the other end can bend upward and enter the top of the heat dissipation protrusion when the deformation temperature is reached. The deformation temperature of the shape memory alloy metal strip is 1-10°C greater than the vaporization phase change temperature of the phase change coolant.

[0029] In this way, when the high-heat area becomes severely hot, and the heat dissipation protrusion reaches its deformation temperature, the shape memory alloy deforms upon heating. One end extends upwards, driving air bubbles from the vertical groove and the internal pores of the heat dissipation protrusion into the phase change coolant. Once the upper end of the shape memory alloy enters the phase change coolant, its temperature decreases, it returns to its original shape, and falls back into the vertical groove. Thus, when the high-heat area becomes excessively hot, the shape memory alloy can automatically repeat this action, better guiding and driving air bubbles generated in the high-heat area upwards into the coolant, thereby improving the heat exchange efficiency of the high-heat area. Furthermore, the higher the temperature and the faster the heat exchange, the faster the shape memory alloy moves, achieving adaptive control.

[0030] In summary, this invention can better cool the high-heat areas of the chip, thereby balancing the overall cooling effect and improving the overall performance of the server. Attached Figure Description

[0031] Figure 1 This is a schematic diagram of the server chip phase change liquid cooling system used in an embodiment of the present invention.

[0032] Figure 2 for Figure 1 A magnified structural diagram of the individual heat dissipation protrusion.

[0033] Figure 3 for Figure 2 The side view shows the shape memory alloy strip in a deformed state.

[0034] Figure 4 for Figure 2 The top view in the image. Detailed Implementation

[0035] The present invention will now be described in further detail with reference to the accompanying drawings and specific embodiments.

[0036] Preferred Implementation: A locally enhanced phase change liquid cooling method for server chips involves immersing a horizontally positioned chip board in a two-phase coolant. The chip board is cooled by the vaporization of the two-phase coolant. After vaporization, the two-phase coolant rises to the upper end of the two-phase coolant chamber, exchanges heat with the cooling device, liquefies, and falls back down. The key feature is that the two-phase coolant is guided to flow upward in the upper space of the high-heat area of ​​the chip board, allowing the bubbles generated on the surface of the high-heat area to reach the upper end of the two-phase coolant chamber more quickly and liquefy.

[0037] In this way, this solution can divert the upper space of the high-heat area of ​​the chip board upwards separately, so that the generated bubbles can reach the upper end of the two-phase coolant chamber for liquefaction more quickly, while the surrounding liquid flows in from below to replenish it. This not only makes the cooling effect of the high-heat area better, but also improves the heat dissipation efficiency and heat dissipation uniformity of other areas due to the increased fluidity of the coolant.

[0038] In practice, the high-heat area is the region where the CPU is located. This allows for more targeted heat dissipation and cooling of the computing area, ensuring stable server performance.

[0039] During implementation, when the surface temperature of the high-heat-generating area exceeds the vaporization temperature of the two-phase coolant and reaches a preset temperature, the bubbles generated on the surface are driven away and enter the two-phase coolant liquid. This can further improve the heat dissipation and cooling effect on the high-heat-generating area.

[0040] In implementation, this method relies on a server chip phase change liquid cooling system, which can be found in [link to documentation]. Figure 1-4As shown, it includes a cooling chamber 1, a horizontally arranged chip board 2 at the lower part of the cooling chamber 1, a phase change coolant 3 immersed in the middle part, a cooling plate 4 at the upper end, a cooling device 5 inside the cooling plate 4, and a flow guide 6 correspondingly arranged above the high heat generation area of ​​the chip board, and an upward-facing fan blade device 7 inside the flow guide 6.

[0041] In this way, the fan blade device can guide the phase change coolant in the high-heat-generating area of ​​the chip board upwards along the guide shroud, thus more quickly moving the vaporized bubbles in the high-heat-generating area upwards and improving the phase change heat transfer efficiency of the high-heat-generating area. Simultaneously, the coolant flows from four directions below the guide shroud to replenish the high-heat-generating area, further enhancing the heat exchange effect on the chip board. In implementation, the cooling device 5 is connected to the heat exchange circulation system, which has a heat dissipation device located outside the server room.

[0042] Among them, a thermoelectric power generation chip 8 is provided on the lower surface of the cooling plate 4 corresponding to the upper port of the guide shroud. The positive and negative output terminals of the thermoelectric power generation chip 8 are connected to the fan blade device 7 as power sources.

[0043] The high-heat bubbles generated in the high-heat area rise to the thermoelectric chip, raising the temperature of its lower surface and creating a significant temperature difference with its upper surface. The resulting electricity powers the fan blades. The higher the heat generated in the high-heat area of ​​the chip, the faster the bubbles rise, the higher the temperature at the bottom of the thermoelectric chip, and the greater the temperature difference, the greater the power generation. This corresponds to a faster fan blade rotation, accelerating bubble rise and improving heat exchange efficiency in the high-heat area. Therefore, it achieves an adaptive heat exchange and cooling effect.

[0044] The lower surface of the cooling plate 4 has a downward protrusion 9 corresponding to the upper end port of the flow guide. The lower protrusion 9 is made of thermally conductive material. The thermoelectric power generation chip 8 is installed on the lower surface of the lower protrusion. The lower surface of the lower protrusion also has a downward flange 10 around its perimeter, forming a groove structure inside.

[0045] In this way, the lower surface of the protrusion can be immersed in the phase change coolant. The bubbles that rise upward through the guide shroud are concentrated into the sink, heating and reliquefying the lower surface of the thermoelectric chip. This prevents the bubbles in the guide shroud from entering the gas phase layer at the top of the phase change coolant and diffusing, which would result in uneven heating of the lower surface of the thermoelectric chip.

[0046] The vertical cross-section of the flow guide 6 is generally shaped like a frustum, wider at the bottom and narrower at the top.

[0047] This allows the bubbles generated in the high-heat area to concentrate and enter the sink on the lower surface of the convex part, thus better heating the thermoelectric chip.

[0048] The flow guide 6 is a mesh structure.

[0049] Among them, the upper surface of the high heat generation area of ​​the chip board 2 has an upwardly arranged heat dissipation protrusion 11, which is made of a porous thermally conductive material.

[0050] This allows for a greater increase in the contact area between the high-heat-generating areas of the chip board and the phase change coolant, thereby improving heat exchange efficiency.

[0051] Among them, the internal diameter of the heat dissipation protrusion 11 gradually increases from bottom to top.

[0052] In this way, the air bubbles inside the heat dissipation protrusion gradually increase in size from bottom to top and then detach from the protrusion and rise upwards.

[0053] The heat dissipation protrusion 11 has multiple rows of vertical grooves 12 arranged on its upper surface. Each vertical groove 12 is provided with a shape memory alloy metal strip 13. One end of the shape memory alloy metal strip 13 is fixed in the vertical groove, and the other end can bend upward and enter the top of the heat dissipation protrusion when the deformation temperature is reached. The deformation temperature of the shape memory alloy metal strip is 1-10℃ higher than the vaporization phase change temperature of the phase change coolant.

[0054] In this way, when the high-heat area becomes severely hot, and the heat dissipation protrusion reaches its deformation temperature, the shape memory alloy deforms upon heating. One end extends upwards, driving air bubbles from the vertical groove and the internal pores of the heat dissipation protrusion into the phase change coolant. Once the upper end of the shape memory alloy enters the phase change coolant, its temperature decreases, it returns to its original shape, and falls back into the vertical groove. Thus, when the high-heat area becomes excessively hot, the shape memory alloy can automatically repeat this action, better guiding and driving air bubbles generated in the high-heat area upwards into the coolant, thereby improving the heat exchange efficiency of the high-heat area. Furthermore, the higher the temperature and the faster the heat exchange, the faster the shape memory alloy moves, achieving adaptive control.

Claims

1. A locally enhanced phase-change liquid cooling method for server chips, comprising immersing a horizontally positioned chip board in a two-phase coolant, cooling the chip board by the vaporization of the two-phase coolant, wherein the vaporized two-phase coolant rises to the upper end of the two-phase coolant chamber, exchanges heat with the cooling device, liquefies, and falls back down, characterized in that, In the upper space of the high-heat area of ​​the chip board, the two-phase coolant is guided to flow upward, so that the bubbles generated on the surface of the high-heat area can reach the upper end of the two-phase coolant chamber for liquefaction more quickly. This method relies on a server chip phase change liquid cooling system, which includes a cooling chamber, a horizontally arranged chip plate at the bottom of the cooling chamber, a phase change coolant immersed in the middle, a cooling plate at the top, and a cooling device inside the cooling plate. A flow guide is provided above the high heat generation area of ​​the chip plate, and an upward-facing fan blade device is provided inside the flow guide. A thermoelectric power generation chip is provided on the lower surface of the cooling plate corresponding to the upper port of the air guide. The positive and negative output terminals of the thermoelectric power generation chip are connected to the fan blade device as power sources. The lower surface of the cooling plate has a downward protrusion corresponding to the upper port of the flow guide. The lower protrusion is made of thermally conductive material. The thermoelectric power generation chip is installed on the lower surface of the lower protrusion. The lower surface of the lower protrusion also has a downward flange around its perimeter, forming a groove structure inside. The upper surface of the high-heat area of ​​the chip board has upward-facing heat dissipation protrusions, which are made of porous thermally conductive material. The upper surface of the heat dissipation protrusion is provided with multiple rows of vertical grooves, and each vertical groove is provided with a shape memory alloy metal strip. One end of the shape memory alloy metal strip is fixed in the vertical groove, and the other end can bend upward and enter the top of the heat dissipation protrusion when the deformation temperature is reached. The deformation temperature of the shape memory alloy metal strip is 1-10℃ higher than the vaporization phase change temperature of the phase change coolant.

2. The locally enhanced phase-change liquid cooling method for server chips according to claim 1, characterized in that, The high-heat area is the region where the CPU is located.

3. The locally enhanced phase-change liquid cooling method for server chips according to claim 1, characterized in that, When the surface temperature of the high-heat area exceeds the vaporization temperature of the two-phase coolant and reaches the preset temperature, the bubbles generated on the surface are driven away from the surface and enter the two-phase coolant liquid.

4. The locally enhanced phase-change liquid cooling method for server chips according to claim 1, characterized in that, The vertical cross-section of the fairing is generally shaped like a frustum, wider at the bottom and narrower at the top.

5. The locally enhanced phase-change liquid cooling method for server chips according to claim 1, characterized in that, The internal diameter of the heat dissipation protrusion gradually increases from bottom to top.

Images