Intensified immersion cooling heat dissipation method and device based on piezoelectric fan

Abstract

The invention discloses an enhanced immersion cooling heat dissipation method and device based on a piezoelectric fan. The method comprises the steps that a plurality of circuit boards are arranged in a heat dissipation box filled with a liquid cooling medium; and a piezoelectric fan is arranged in an area where the circuit board hinders the flowing of the liquid cooling medium. According to the invention, local enhanced heat dissipation can be carried out on the immersion cooling system, and a flowing dead zone in the immersion heat dissipation device is avoided, so that the heat dissipation efficiency of the system is greatly improved.

Description

Technical Field

[0001] The present invention belongs to the technical field of heat dissipation of electronic information equipment, and in particular relates to a piezoelectric fan-based enhanced immersion cooling heat dissipation method and device. Background Art

[0002] With the rapid development of computing-intensive applications such as artificial intelligence, the Internet of Things, cryptocurrency, AR / VR, and the growing computing demand, data centers are gradually developing towards "high performance, high density, and high energy consumption". Data centers consume more and more electricity. They are roughly composed of communication and network equipment, power supply and distribution systems, lighting and auxiliary equipment, and cooling systems. The energy consumption of the cooling part accounts for about 40% of the total energy consumption of data centers.

[0003] At present, common liquid cooling methods include cold plate, spray and immersion. Among them, immersion liquid cooling has the highest heat transfer efficiency and can avoid local hot spots. The thermal design power consumption of chips has gradually increased, and some chips have even reached 360W. This poses a serious challenge to the heat dissipation of server chips using the more common air-cooling technology used in traditional data centers. The heat flux density has reached the limit of air-cooling technology. Higher heat flux density can easily lead to a large amount of heat being unable to be discharged from the chip in time.

[0004] In a single-phase immersion liquid cooling system, all heat-generating components of electronic equipment are completely immersed in a circulating non-conductive coolant. The heat generated by the equipment is directly transferred to the coolant. The coolant of single-phase immersion liquid cooling usually has a high boiling point. After absorbing heat, the coolant does not undergo phase change and always remains in a liquid state. Single-phase immersion liquid cooling drives the circulation of the coolant through natural convection or a pump. The circulating heat dissipation process driven by natural convection utilizes the characteristic that the volume expands and the density decreases after the liquid is heated. The hotter coolant will naturally float up and then be cooled by a heat exchanger connected to an external cooling loop. The cooled liquid naturally sinks under the action of gravity to complete the circulating heat dissipation. Compared with natural convection, the method of driving the circulating coolant with a pump can more effectively improve the cooling capacity.

[0005] However, when using single-phase immersion cooling with natural convection, the overall heat dissipation effect is poor due to the relatively low thermal conductivity of the coolant, and two-phase immersion cooling has a certain boiling lag phenomenon, which causes the chip temperature to be too high when boiling begins. At the same time, when a pump-driven circulation method is adopted, although immersion cooling can achieve uniform heat dissipation of multiple electronic devices in the box at the same time through array arrangement, if the structure of the electronic equipment that needs to dissipate heat is relatively complex, when the heat generation of different parts of the electronic equipment varies greatly, the coolant may form a flow dead zone in the local area of ​​the electronic equipment, which hinders the normal operation circulation of the coolant and causes the temperature in this area to be too high. Summary of the invention

[0006] The purpose of the present invention is to overcome the defects of the prior art and provide a piezoelectric fan-based enhanced immersion cooling heat dissipation method and device, which can locally enhance the heat dissipation of the immersion cooling system, avoid the occurrence of flow dead zones in the immersion heat dissipation device, and thus greatly improve the heat dissipation efficiency of the system.

[0007] The object of the present invention is achieved through the following technical solutions:

[0008] A piezoelectric fan-based enhanced immersion cooling heat dissipation method, comprising:

[0009] Placing a plurality of circuit boards in a heat dissipation box filled with a liquid cooling medium;

[0010] A piezoelectric fan is arranged in a region of the circuit board that hinders the flow of the liquid cooling medium.

[0011] In one embodiment, along the flow direction of the liquid cooling medium, the piezoelectric fans are sequentially arranged in the gap between two adjacent circuit boards;

[0012] Through this implementation, the driving blades of the piezoelectric fan are used to generate bending resonance to disturb the flow of the liquid cooling medium, thereby enhancing the convection effect and avoiding the occurrence of flow dead zones.

[0013] In one embodiment, it further comprises:

[0014] The piezoelectric fan is arranged on the surface of the circuit board, and the piezoelectric fan is arranged close to the heat generating components on the circuit board;

[0015] Through this implementation, the piezoelectric fan has a small power supply, a simple structure, is directly integrated on the circuit board, and can be flexibly arranged near the heat-generating components to enhance heat dissipation in the area.

[0016] The present invention also provides a piezoelectric fan-based enhanced immersion cooling heat dissipation device, comprising a heat dissipation box body and a plurality of circuit boards sequentially arranged in the heat dissipation box body, wherein the heat dissipation box body is filled with a liquid cooling medium;

[0017] Wherein, a heat sink is also arranged in the liquid cooling medium, and the heat sink is located in the area of ​​the circuit board that hinders the flow of the liquid cooling medium.

[0018] In one embodiment, the heat sink includes a plurality of first piezoelectric fans sequentially arranged between two adjacent circuit boards along a circulation direction of the liquid cooling medium.

[0019] In one embodiment, the heat sink further includes a second piezoelectric fan disposed on the surface of the circuit board, and the second piezoelectric fan is close to heat-generating components on the circuit board.

[0020] In one embodiment, the first piezoelectric fan and the second piezoelectric fan each include a driver and blades connected to the driver.

[0021] In one embodiment, a plurality of the first piezoelectric fans are all mounted on a power supply support.

[0022] In one embodiment, the liquid cooling medium is electronic fluorinated liquid.

[0023] The beneficial effects of the present invention are:

[0024] Piezoelectric fans are used for local enhanced heat dissipation, generating bending resonance in the area of ​​the circuit board that hinders the flow of liquid cooling medium, thereby disturbing the liquid cooling medium. The flow rate can reach 3m / s to 5m / s, which has a significant enhanced convection effect and avoids the appearance of flow dead zones in the immersion cooling device, thereby greatly improving the heat dissipation efficiency of the system. BRIEF DESCRIPTION OF THE DRAWINGS

[0025] The present invention will be described in more detail below based on embodiments and with reference to the accompanying drawings, wherein:

[0026] Figure 1 A schematic diagram showing the liquid flow rate of a conventional top-in, bottom-out immersion cooling device;

[0027] Figure 2 A schematic diagram showing the liquid flow rate of a conventional top-in, top-out immersion cooling device;

[0028] Figure 3 A schematic diagram showing the structure of the piezoelectric fan of the present invention is shown;

[0029] Figure 4 A schematic structural diagram showing an embodiment of an immersion cooling and heat dissipation device of the present invention;

[0030] Figure 5 A schematic structural diagram showing another embodiment of the immersion cooling and heat dissipation device of the present invention;

[0031] Figure 6 A schematic diagram showing the structure of the piezoelectric fan of the present invention installed on a circuit board;

[0032] In the drawings, like reference numerals are used for like parts. The drawings are not necessarily to scale.

[0033] Reference numerals:

[0034] 1-circuit board, 2-piezoelectric fan, 3-heat generating component, 4-power supply support, 5-condenser, 201-driver, 202-blade. DETAILED DESCRIPTION

[0035] The present invention will be further described below in conjunction with the accompanying drawings.

[0036] In single-phase immersion cooling, the pump-driven circulation method can achieve uniform heat dissipation of multiple electronic devices in the box through array arrangement at the same time. However, if the structure of the electronic equipment to be cooled is relatively complex and the heat generation of different parts of the electronic equipment varies greatly, the coolant may form a dead zone in the local area of ​​the electronic equipment, which hinders the normal working circulation of the coolant and causes the temperature in this area to be too high. Figure 1 and Figure 2 As shown, even if different inlets and outlets are changed, the liquid flow speed near the electronic device closer to the inlet is faster, and the liquid flow speed near the electronic device farther from the inlet is slower. As the complexity of the electronic device increases, there will be more and more dead zones, which seriously restricts the heat dissipation performance of immersion cooling.

[0037] The present invention provides a piezoelectric fan-based enhanced immersion cooling heat dissipation method, comprising:

[0038] Placing a plurality of circuit boards in a heat dissipation box filled with a liquid cooling medium;

[0039] A piezoelectric fan is provided in an area of ​​the circuit board that hinders the flow of the liquid cooling medium;

[0040] It should be noted that the piezoelectric fan generates an alternating electric field by the driving circuit, driving the blades to produce bending resonance, and the piezoelectric fan has a small structure size, which is convenient for arrangement in the dead zone of flow. When it generates bending resonance and then disturbs the flow of liquid cooling medium, the flow rate can reach 3m / s to 5m / s, and the convection enhancement effect is obvious, which can avoid the following problems: Figure 1 and Figure 2 The dead zone of the flow shown greatly improves the heat dissipation efficiency of the system;

[0041] Specifically, along the flow direction of the liquid cooling medium, the piezoelectric fans are sequentially arranged in the gap between two adjacent circuit boards;

[0042] It should be noted that multiple circuit boards are often arranged in an array, and the flow speed of the liquid cooling medium in the area between two adjacent circuit boards is slow. In addition, there are heat-generating components in this area, resulting in poor heat dissipation. The piezoelectric fan is set in the gap between two adjacent circuit boards to generate bending resonance and disturb the flow of the liquid cooling medium, thereby improving the effect of immersion heat dissipation.

[0043] Furthermore, it also includes:

[0044] A piezoelectric fan is arranged on the surface of the circuit board, and the piezoelectric fan is arranged close to the heat generating components on the circuit board. That is, since the piezoelectric fan has low power, low power supply voltage, small structural size, and convenient customized production, the piezoelectric fan can be directly installed on the circuit board according to the position of the heat generating components on the circuit board to assist in heat dissipation of the nearby heat generating components;

[0045] The present invention also provides an enhanced immersion cooling and heat dissipation device based on a piezoelectric fan 2, such as Figures 3 to 5 As shown, it includes a heat dissipation box body and a plurality of circuit boards 1 sequentially arranged in the heat dissipation box body, and the heat dissipation box body is filled with a liquid cooling medium;

[0046] Wherein, a heat sink is also provided in the liquid cooling medium, and the heat sink is located in the area of ​​the heating circuit board 1 that hinders the flow of the liquid cooling medium;

[0047] Specifically, the heat sink includes a plurality of piezoelectric fans 2 sequentially arranged between two adjacent circuit boards 1 along the circulation direction of the liquid cooling medium, and the plurality of piezoelectric fans 2 are all mounted on a power supply support 4, and the power supply support 4 is used to connect the plurality of piezoelectric fans 2 together and supply power to them;

[0048] It should be noted that if Figure 4 As shown, for the pump-driven circulating immersion cooling system, the heat dissipation box is filled with liquid cooling medium, and convective heat exchange is performed by relying on the flow of the liquid cooling medium generated during the process of entering and exiting the box. In this embodiment, the piezoelectric fan 2 is arranged between two adjacent circuit boards 1, which makes up for the shortcomings of the pump-driven circulating immersion cooling, effectively avoids the problem of flow dead zone, and improves the heat dissipation effect. Figure 5 As shown, for the two-phase flow immersion cooling system, the liquid cooling medium filled in the heat dissipation box body only needs to immerse the electronic equipment. When the electronic equipment is working and generating heat, the liquid cooling medium will boil and evaporate, and will condense when encountering the condenser 5. After condensation, it will drip back under the action of gravity. In this embodiment, the piezoelectric fan 2 arranged between the circuit boards 1 can enhance the boiling heat exchange and further improve the heat exchange effect, that is, it is applicable to various forms of immersion cooling systems;

[0049] In one embodiment, Figure 6 As shown, the heat sink also includes a second piezoelectric fan 2 arranged on the surface of the heat-generating circuit board 1, and the second piezoelectric fan 2 is close to the heat-generating component 3 on the heat-generating circuit board 1. That is, since the piezoelectric fan 2 has low power, low power supply voltage, small structural size, and convenient customized production, the piezoelectric fan 2 can be directly installed on the circuit board 1 according to the position of the heat-generating component 3 on the circuit board 1 to assist in heat dissipation of the nearby heat-generating component 3;

[0050] Specifically, the piezoelectric fan 2 includes a driver 201 and blades 202 connected to the driver 201, and the liquid cooling medium is an electronic fluorinated liquid;

[0051] In the description of the present invention, it is necessary to understand that the terms "upper", "lower", "bottom", "top", "front", "back", "inside", "outside", "left", "right", etc. indicate orientations or positional relationships based on the orientations or positional relationships shown in the accompanying drawings, and are only for the convenience of describing the present invention and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as a limitation on the present invention.

[0052] Although the present invention is described herein with reference to specific embodiments, it should be understood that these embodiments are merely examples of the principles and applications of the present invention. It should therefore be understood that many modifications may be made to the exemplary embodiments and that other arrangements may be devised without departing from the spirit and scope of the present invention as defined by the appended claims. It should be understood that the various dependent claims and features described herein may be combined in a manner different from that described in the original claims. It should also be understood that features described in conjunction with individual embodiments may be used in other described embodiments.

Claims

1. A piezoelectric fan-based enhanced immersion cooling method, characterized in that: include: Placing a plurality of circuit boards in a heat dissipation box filled with a liquid cooling medium; A piezoelectric fan is arranged in a region of the circuit board that hinders the flow of the liquid cooling medium.

2. The enhanced immersion cooling and heat dissipation method based on a piezoelectric fan according to claim 1 is characterized in that: The piezoelectric fans are sequentially arranged in the gap between two adjacent circuit boards along the flow direction of the liquid cooling medium.

3. The enhanced immersion cooling and heat dissipation method based on a piezoelectric fan according to claim 2 is characterized in that: Also includes: The piezoelectric fan is arranged on the surface of the circuit board, and the piezoelectric fan is arranged close to the heat generating components on the circuit board.

4. An enhanced immersion cooling and heat dissipation device based on a piezoelectric fan, characterized in that: It comprises a heat dissipation box body and a plurality of circuit boards sequentially arranged in the heat dissipation box body, wherein the heat dissipation box body is filled with a liquid cooling medium; Wherein, a heat sink is also arranged in the liquid cooling medium, and the heat sink is located in the area of ​​the circuit board that hinders the flow of the liquid cooling medium.

5. The piezoelectric fan-based enhanced immersion cooling and heat dissipation device according to claim 4, characterized in that: The heat sink comprises a plurality of first piezoelectric fans which are sequentially arranged between two adjacent circuit boards along the circulation direction of the liquid cooling medium.

6. The piezoelectric fan-based enhanced immersion cooling and heat dissipation device according to claim 5, characterized in that: The heat sink also includes a second piezoelectric fan disposed on the surface of the circuit board, and the second piezoelectric fan is close to the heat generating components on the circuit board.

7. The piezoelectric fan-based enhanced immersion cooling and heat dissipation device according to claim 6, characterized in that: The first piezoelectric fan and the second piezoelectric fan both include a driver and blades connected to the driver.

8. The piezoelectric fan-based enhanced immersion cooling and heat dissipation device according to claim 7, characterized in that: The plurality of first piezoelectric fans are all mounted on a power supply support.

9. The piezoelectric fan-based enhanced immersion cooling and heat dissipation device according to claim 4, characterized in that: The liquid cooling medium is electronic fluorinated liquid.

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