A PCM-based needle-fins composite heat sink structure

Abstract

The utility model discloses a PCM base needle fin composite radiator structure, including intermediate conductor, be equipped with liquid cooling cavity, liquid inlet and liquid outlet in intermediate conductor, liquid cooling cavity includes the liquid inlet area, microchannel area and liquid outlet area who set gradually along liquid cooling cavity flow direction, and liquid inlet and liquid outlet are connected with liquid inlet area and liquid outlet area respectively, microchannel area is equipped with several needle fins made of PCM material, the clearance between needle fin is cooperated and forms the microchannel that allows liquid cooling cavity to pass. Because PCM is a kind of phase change material with high latent heat characteristics, heat absorption capacity is very strong, in addition to the big specific area of needle fin structure and excellent heat transfer performance, the needle fin made of PCM can realize the efficient conversion of heat in the storage and release process, when facing transient pulse, response is very fast, can promptly dissipate the high heat flow of chip instantaneous release, satisfies the heat dissipation of non-steady-state heat pulse condition electronic chip.

Description

Technical Field

[0001] This utility model relates to the field of electronic device cooling technology, and in particular to a PCM-based pin-fin composite heat sink structure. Background Technology

[0002] Chips are among the most critical components in modern computers, robots, electronic devices, and other industrial equipment. With the rapid development of technology, chip power output and assembly density are increasing, and they are becoming increasingly integrated into packaging designs. This leads to smaller chip sizes but larger heat dissipation per unit area, resulting in a dramatic increase in heat flux density and ultimately, higher chip temperatures. Excessively high operating temperatures can severely or even irreversibly affect the normal operation of chips and the reliable operation of equipment. The well-known 10°C rule states that the reliability of electronic components is closely related to temperature. When the temperature is between 70°C and 80°C, the reliability of electronic components decreases by 50% for every 10°C increase. The quality of heat dissipation directly affects the stability of the chip.

[0003] Conventional natural and forced air cooling methods are no longer sufficient to meet the heat dissipation requirements of chips. Therefore, researchers have proposed emerging technologies such as micro heat pipes, vacuum vapor chambers, carbon nanotubes, and microchannels. Among these, microchannel technology, which utilizes fluid cooling, has received the most extensive research. Microchannel heat sinks were first proposed by Tucherman and Pease in 1981. Compared to conventional heat sinks, microchannel heat sinks offer advantages such as a large heat exchange area, high heat exchange capacity, and small size.

[0004] Traditional microchannels mostly employ a finned structure, with fins extending along the coolant flow direction and spaced apart in a direction perpendicular to the coolant flow. Adjacent fins form microchannels that allow coolant to pass through. The fins are typically made of metals with good heat dissipation properties, such as Gu and Al. However, this type of heat sink exhibits a delayed response to transient thermal pulses, failing to dissipate the high heat flux released by the chip in a timely manner. This leads to a sudden temperature rise and uneven heat dissipation, making it unsuitable for heat dissipation under unsteady thermal pulse conditions. Utility Model Content

[0005] This invention provides a PCM-based pin-fin composite heat sink structure, which can solve the problem that existing microchannel heat sinks have a delayed response when dealing with transient thermal pulses, and cannot dissipate the high heat flow released by the chip in time, resulting in a sudden temperature rise and uneven heat dissipation, and cannot meet the heat dissipation requirements under non-steady-state thermal pulse conditions.

[0006] To achieve the above objectives, this utility model provides a PCM-based needle-fin composite heat sink structure, including an intermediate conductor. The intermediate conductor is provided with a liquid cooling cavity, a liquid inlet, and a liquid outlet. The liquid cooling cavity includes a liquid inlet area, a microchannel area, and a liquid outlet area arranged sequentially along the coolant flow direction. The liquid inlet and the liquid outlet are respectively connected to the liquid inlet area and the liquid outlet area. The microchannel area is provided with a plurality of needles made of PCM material. The gaps between the needles cooperate to form microchannels that allow the liquid cooling cavity to pass through.

[0007] In one embodiment, the intermediate conductor includes a substrate and a cover plate connected together, the cover plate being located on one side of the substrate, and the liquid cooling cavity being formed on the side of the substrate facing the cover plate.

[0008] In one embodiment, the cover plate and the substrate are connected by adhesive bonding, welding or high-temperature bonding.

[0009] In one embodiment, the needle fin and the substrate are processed separately, and the needle fin is connected to the substrate by means of adhesive bonding, welding or high-temperature bonding.

[0010] In one embodiment, the microchannel region has a hotspot concentration area, and the density of the needle fins disposed on the hotspot concentration area is greater than the density of the needle fins disposed on the rest of the microchannel region.

[0011] In one embodiment, the ratio of the length of the needle fin to the depth of the liquid cooling cavity ranges from 0.5 to 1.

[0012] In one embodiment, the outer surface of the needle fin is provided with protrusions or fins made of PCM material.

[0013] In one embodiment, the needle fins are arranged in a matrix in the liquid cooling cavity.

[0014] In one embodiment, a plurality of the needle fins are arranged in at least two rows along the flow direction of the coolant, with adjacent rows of needle fins arranged alternately.

[0015] In one embodiment, the needle fin is a porous columnar structure made of PCM material composited with expanded graphite.

[0016] The above-mentioned solution of this utility model has the following beneficial effects: This invention utilizes a series of PCM (Polycarbonate) fins within a microchannel. The gaps between these fins interlock to form a microchannel that allows the liquid cooling cavity to pass through. PCM, a phase change material with high latent heat, possesses exceptional heat absorption capacity. When the chip's heat load surges, the PCM fins rapidly absorb the large amount of heat generated by the chip, slowing down the temperature rise. Combined with the large specific area and excellent thermal conductivity of the fin structure, the PCM fins can uniformly and rapidly transfer the heat absorbed from the chip to the liquid cooling cavity, effectively reducing the formation of localized high-pass hotspots on the chip. Therefore, this invention achieves highly efficient heat conversion during storage and release through the synergistic effect of PCM and the fins. It responds very quickly to transient pulses, promptly dissipating the high heat flow released instantaneously by the chip, meeting the heat dissipation requirements of electronic chips under unsteady thermal pulse conditions. This ensures that the heat sink maintains a stable temperature distribution for the chip under various operating conditions, guaranteeing the chip's reliability and lifespan.

[0017] Other beneficial effects of this invention will be described in detail in the following detailed description section. Attached Figure Description

[0018] Figure 1 This is a three-dimensional structural schematic diagram of a PCM-based pin-fin composite heat sink structure shown in some embodiments of this application; Figure 2 This is an exploded view of a PCM-based pin-fin composite heat sink structure shown in some embodiments of this application; Figure 3 for Figure 2 Enlarged view of the area circled in the middle circle A; Figure 4 This is a regional distribution diagram of the liquid cooling cavity shown in some embodiments of this application; Figure 5 This is a top view of the substrate structure shown in some embodiments of this application; Figure 6 This is a schematic diagram of the three-dimensional structure of the needle fin shown in some embodiments of this application. Figure 1 ; Figure 7 This is a schematic diagram of the three-dimensional structure of the needle fin shown in some embodiments of this application. Figure 2 .

[0019] [Explanation of Labels in the Attached Image] 10-Intermediate conductor-; 20-Substrate; 21-Liquid cooling cavity; 211-Liquid inlet area; 212-Liquid outlet area; 213-Microchannel area; 2131-Hot spot concentration area; 22-Fin; 221-Protrusion; 222-Fin; 30-Cover plate; 31-Liquid inlet; 32-Liquid outlet. Detailed Implementation

[0020] To make the technical problems, solutions, and advantages of this utility model clearer, a detailed description will be provided below with reference to the accompanying drawings and specific embodiments. Obviously, the described embodiments are only some, not all, of the embodiments of this utility model. All other embodiments obtained by those skilled in the art based on the embodiments of this utility model without creative effort are within the scope of protection of this utility model. Furthermore, the technical features involved in the different embodiments of this utility model described below can be combined with each other as long as they do not conflict with each other.

[0021] In the description of this utility model, it should be noted that the terms "center," "upper," "lower," "left," "right," "vertical," "horizontal," "inner," and "outer," etc., indicating the orientation or positional relationship, are based on the orientation or positional relationship shown in the accompanying drawings and are only for the convenience of describing this utility model and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation, and therefore should not be construed as a limitation of this utility model. Furthermore, the terms "first," "second," and "third" are used for descriptive purposes only and should not be construed as indicating or implying relative importance.

[0022] In the description of this utility model, it should be noted that, unless otherwise explicitly specified and limited, the terms "installation," "connection," and "joining" should be interpreted broadly. For example, they can refer to a locking connection, a detachable connection, or an integral connection; they can refer to a mechanical connection or an electrical connection; they can refer to a direct connection or an indirect connection through an intermediate medium; and they can refer to the internal connection of two components. Those skilled in the art can understand the specific meaning of the above terms in this utility model based on the specific circumstances.

[0023] like Figure 1 As shown, an embodiment of this utility model provides a method for reference. Figures 1 to 7This invention relates to a PCM-based needle-fin composite heat sink structure, comprising an intermediate conductor 10, which contains a liquid cooling cavity 21, a liquid inlet 31, and a liquid outlet 32. The liquid cooling cavity 21 includes an inlet region 211, a microchannel region 213, and an outlet region 212 arranged sequentially along the flow direction of the liquid cooling cavity 21. The inlet 31 and the outlet 32 ​​are respectively connected to the inlet region 211 and the outlet region 212. The microchannel region 213 is provided with microchannels that allow the liquid cooling cavity 21 to pass through. PCM is a phase change material with high latent heat characteristics and very strong heat absorption capacity. When the heat load of the chip surges, the needle fins 22 made of PCM can quickly absorb a large amount of heat generated by the chip, delaying the rise in chip temperature. Combined with the large specific area and excellent heat transfer performance of the needle fin structure, the needle fins 22 made of PCM can uniformly and quickly transfer the heat absorbed from the chip to the liquid cooling cavity 21, thereby effectively reducing the formation of local high-pass hot spots on the chip.

[0024] When the heat sink is working, the liquid cooling cavity 21 first flows from the inlet 31 into the inlet area 211, and then flows from the inlet area 211 into the microchannel with the microchannel area 213. During the flow through the microchannel, the liquid cooling cavity 21 quickly absorbs the heat generated on the chip through the needle fins 22 made of PCM material, and after absorbing the heat, it flows into the outlet area 212, and finally flows out of the intermediate conductor 10 through the outlet 32.

[0025] Therefore, this utility model achieves efficient heat conversion during storage and release through the synergistic effect of PCM and fins 22. When facing transient pulses, it responds very quickly and can dissipate the high heat flow released by the chip in a timely manner, meeting the heat dissipation requirements of electronic chips under non-steady-state thermal pulse conditions. This ensures that the heat sink can maintain a stable temperature distribution of the chip under various operating conditions, thus ensuring the reliability and service life of the chip.

[0026] Please see Figure 2 In one embodiment of this application, the intermediate conductor 10 includes a substrate 20 and a cover plate 30 connected to each other. The cover plate 30 is located on one side of the substrate 20, and the liquid cooling cavity 21 is formed on the side of the substrate 20 facing the cover plate 30.

[0027] Optionally, the cover plate 30 and the substrate 20 may be made of LTCC, Cu, or Al. LTCC, Cu, or Al are all materials with good heat dissipation properties. Using these materials to make the cover plate 30 and the substrate 20 allows the heat generated by the chip to be quickly transferred to the liquid cooling cavity 21 through the intermediate conductor 10. Of course, the materials used to make the cover plate 30 and the substrate 20 are not limited to these; other materials that can achieve rapid heat transfer can also be used to make the cover plate 30 and the substrate 20.

[0028] Optionally, the intermediate conductor 10 may be square or other shapes. The shape of the intermediate conductor 10 may be modified according to the shape of the chip so that the heat sink of this invention can achieve the beneficial effect of maximizing heat dissipation over the chip area.

[0029] In one embodiment of this application, the inlet 31 and the outlet 32 ​​are located on the same side of the intermediate conductor 10. For example, as Figure 2 As shown, both the inlet 31 and the outlet 32 ​​are disposed on the cover plate 30. Alternatively, the inlet 31 and the outlet 32 ​​may be disposed on the side of the substrate 20 facing away from the cover plate 20. In other alternative embodiments, the outlet 32 ​​and the inlet 31 may be disposed on different sides of the intermediate conductor 10. For example, the inlet 31 may be disposed on the cover plate 30, and the outlet 32 ​​on the side of the substrate 20 facing away from the cover plate 30. Another example is that the inlet 31 may be disposed on the side of the substrate 20 facing away from the cover plate 30, and the outlet 32 ​​on the cover plate 30.

[0030] In one embodiment of this application, the connection between the cover plate 30 and the substrate 20 is non-removable. For example, the cover plate 30 and the substrate 20 are connected by adhesive, welding, or high-temperature bonding. These connection methods not only ensure the sealing between the cover plate 30 and the substrate 20, but also make the overall volume of the intermediate conductor 10 small, suitable for heat dissipation of chips that are moving towards miniaturization. In other optional embodiments, the connection between the cover plate 30 and the substrate 20 can be made detachable, for example, the cover plate 30 and the substrate 20 are connected by screws, and a sealing ring is provided between the cover plate 30 and the substrate 20 to ensure that the liquid cooling cavity 21 in the liquid cooling cavity 21 does not flow out from between the cover plate 30 and the substrate 20.

[0031] In one embodiment of this application, the fins 22 and the substrate 20 are manufactured separately, and the fins 22 are connected to the substrate 20 by adhesive bonding, welding, or high-temperature bonding. Manufacturing the fins 22 and the substrate 20 separately allows the substrate 20 to be made of other non-PCM materials with good heat transfer properties and lower cost, thereby reducing manufacturing costs.

[0032] Optionally, the cross-section of the needle fin 22 may be circular, square, triangular, rhomboid, elliptical, or the like.

[0033] In one embodiment of this application, such as Figure 3 As shown, the outer surface of the needle fin 22 is smoothly formed. In other alternative embodiments, the outer surface of the needle fin 22 may be formed with a material such as PCM. Figure 6 The convex point 221 shown or as Figure 7The fins 222 shown have hemispherical bumps 221. The bumps 221 and fins 222 can be fabricated on the fins 22 using 3D printing. The bumps 221 / fins 22 increase the specific area of ​​the fins 22, further aiding in heat dissipation from the chip. Furthermore, the bumps 221 / fins 222 also act as a barrier to the liquid cooling cavity 21, creating turbulence and accelerating and enhancing heat dissipation from the chip. In other optional embodiments, the fins 22 can be configured as porous columnar structures made of PCM material composited with expanded graphite. The porous columnar structure of the fins 22 increases the contact area between the fins 22 and the liquid cooling cavity 21, significantly improving the thermal response speed of the fins 22 to the chip.

[0034] In one embodiment of this application, such as Figure 2 As shown, the needle fins 22 are arranged in an N-row, M-column matrix within the liquid cooling cavity 21. The depth of the liquid cooling cavity 21 is defined as H, the length of the needle fins 22 as L, the cross-sectional diameter or side length of the needle fins 22 as L1, the distance between adjacent needle fins 22 along the X direction as L2, the distance between adjacent needle fins 22 along the Y direction as L3, and the distance between the outermost needle fin 22 and the sidewall of the liquid cooling cavity 21 as L4. The depth of the liquid cooling cavity 21 is H. L, L1, L2, L3, L4, and H are all set at the millimeter or micrometer level. The ratio of the length of the needle fin 22 to the height of the depth H of the liquid cooling cavity 21 ranges from 0.5 to 1.

[0035] In other alternative embodiments, a plurality of needle fins 22 may be arranged in N rows within the microchannel region 213, with the N rows of needle fins arranged sequentially at intervals along the flow direction of the coolant, and adjacent rows of needle fins 22 being staggered.

[0036] In other feasible embodiments, such as Figure 4 and Figure 5 As shown, a hotspot concentration section 2131 can be set on the microchannel region 213 according to the local high-pass hotspot area of ​​the chip. The density of the pins 22 set on the hotspot concentration section 2131 is greater than the density of the pins 22 set on other parts of the microchannel region 213, so as to increase the overall heat transfer area of ​​the pins 22 on the hotspot concentration section 2131, thereby achieving the beneficial effect of rapid heat dissipation of the local high-pass hotspot area of ​​the chip. The number of hotspot concentration sections 2131 can be set according to the parts that are prone to generating high-power hotspots found during the chip use, and can be one, two or more.

[0037] The above description is the preferred embodiment of this utility model. It should be noted that for those skilled in the art, several improvements and modifications can be made without departing from the principle of this utility model, and these improvements and modifications should also be considered within the protection scope of this utility model.

Claims

1. A PCM-based pin-fin composite heat sink structure, characterized in that, The device includes an intermediate conductor, which contains a liquid cooling cavity, a liquid inlet, and a liquid outlet. The liquid cooling cavity includes an inlet area, a microchannel area, and an outlet area arranged sequentially along the flow direction of the coolant. The inlet and the outlet are respectively connected to the inlet area and the outlet area. The microchannel area is provided with a plurality of needle fins made of PCM material. The gaps between the needle fins are matched to form microchannels that allow the liquid cooling cavity to pass through.

2. The PCM-based pin-fin composite heat sink structure according to claim 1, characterized in that, The intermediate conductor includes a substrate and a cover plate connected together, the cover plate being located on one side of the substrate, and the liquid cooling cavity being formed on the side of the substrate facing the cover plate.

3. The PCM-based pin-fin composite heat sink structure according to claim 2, characterized in that, The cover plate and the substrate are connected by adhesive bonding, welding or high-temperature bonding.

4. The PCM-based pin-fin composite heat sink structure according to claim 2, characterized in that, The needle fin and the substrate are processed separately, and the needle fin is connected to the substrate by means of bonding, welding or high-temperature bonding.

5. The PCM-based pin-fin composite heat sink structure according to claim 1, characterized in that, The microchannel region has a hotspot concentration area, and the density of the needle fins disposed on the hotspot concentration area is greater than the density of the needle fins disposed on the rest of the microchannel region.

6. The PCM-based pin-fin composite heat sink structure according to claim 1, characterized in that, The ratio of the length of the needle fin to the depth of the liquid cooling cavity ranges from 0.5 to 1.

7. The PCM-based pin-fin composite heat sink structure according to claim 1, characterized in that, The outer surface of the needle fin is provided with protrusions or fins made of PCM material.

8. The PCM-based pin-fin composite heat sink structure according to claim 1, characterized in that, The needle fins are arranged in a matrix within the liquid cooling cavity.

9. The PCM-based pin-fin composite heat sink structure according to claim 1, characterized in that, The fins are arranged in at least two rows along the flow direction of the coolant, with adjacent rows of fins staggered.

10. The PCM-based pin-fin composite heat sink structure according to claim 1, characterized in that, The needle fin is a porous columnar structure made of PCM material composited with expanded graphite.

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