TW202411587A - Two-phase immersion-cooling heat-dissipation composite structure having high-porosity solids and high-thermal-conductivity fins - Google Patents

Abstract

A two-phase immersion-cooling heat-dissipation composite structure having high-porosity solids and high-thermal-conductivity fins is provided. The composite structure includes a substrate, a plurality of fins and more than one high porosity solids. The substrate has opposite first and second surfaces. The second surface of the substrate is used for contacting the heat-generating element immersed in the two-phase coolant. The first surface of the substrate is connected with the fins. And, at least one of the high porosity solid is located at the first surface of the substrate and is connected between two adjacent fins. The high porosity solid is formed with a plurality of closed pores and a plurality of open pores. The predetermined volume ratio of the high porosity solid to the porous fin is greater than 0.25.

Description

Two-phase immersion composite heat sink structure with high porosity solid and high thermal conductivity fin

The present invention relates to a heat dissipation structure, in particular to a two-phase immersion composite heat dissipation structure having a solid body with high porosity and a fin with high thermal conductivity.

Immersion cooling technology is to immerse the heat generating components (such as servers, disk arrays, etc.) directly in a non-conductive cooling liquid, so that the cooling liquid absorbs heat and evaporates to take away the heat energy generated by the operation of the heat generating components. In addition, if a heat sink fin is used in conjunction with the cooling liquid, there will be a lack of nucleation points that can generate bubbles. If a porous structure is used in conjunction with the cooling liquid, although the nucleation points for generating bubbles can be increased, the disadvantage of heat conduction in the vertical direction will cause a decrease in thermal performance. Therefore, how to dissipate heat more effectively through immersion cooling technology has always been a problem that the industry needs to solve.

In view of this, the inventor has been engaged in the development and design of related products for many years and feels that the above-mentioned deficiencies can be improved. Therefore, he has conducted intensive research and applied academic theories, and finally proposed the present invention which has a reasonable design and effectively improves the above-mentioned deficiencies.

The technical problem to be solved by the present invention is to provide a two-phase immersion composite heat dissipation structure with a solid body having high porosity and a fin having high thermal conductivity in view of the shortcomings of the prior art.

The present invention provides a two-phase immersion composite heat sink structure having a high-porosity solid body and a high-thermal conductivity fin, comprising: a heat sink base, a plurality of high-thermal conductivity fins, and one or more high-porosity solid bodies, wherein the heat sink base has a first surface and a second surface opposite to each other, wherein the second surface of the heat sink base is used to form contact with a heat generating element immersed in a two-phase cooling liquid, and the heat sink base has a heat sink having ... The first surface is connected to the plurality of high thermal conductivity fins, and more than one high porosity entity is located on the first surface of the heat dissipation base and connected between the side walls of the adjacent high thermal conductivity fins and arranged in a staggered manner, and the high porosity entity is formed with a plurality of closed holes and a plurality of open holes, and a predetermined volume ratio of the high porosity entity to the high thermal conductivity fin is greater than 0.25.

In a preferred embodiment, the high thermal conductivity fin is made of a metal selected from the group consisting of copper, copper alloy, aluminum, and aluminum alloy.

In a preferred embodiment, the high thermal conductivity fin is formed by bending, forging, extrusion, or powder sintering.

In a preferred embodiment, the high thermal conductivity fin is a pin-type fin or a sheet fin, and the thermal conductivity of the high thermal conductivity fin is greater than 300 W/m.K.

In a preferred embodiment, the volume ratio of the high porosity body to the high thermal conductivity fin is between 0.25 and 2.25.

In a preferred embodiment, the porosity of the high porosity entity is greater than the porosity of the high thermal conductivity fin, and the porosity of the high porosity entity is greater than 20% and less than 70%.

In a preferred embodiment, the height of the high porosity entity is higher than 1 mm, and the height of the high porosity entity is between 10% and 150% of the height of the high thermal conductivity fin.

In a preferred embodiment, the high-porosity body is formed by sintering metal powder, and the median particle size (D50) of the metal powder used to form the high-porosity body is between 30 μm and 800 μm.

In a preferred embodiment, the high-porosity entity is formed by chemically corroding the substrate with a chemical agent, and the chemical agent used to form the high-porosity entity is one of a phosphoric acid-based micro-etching agent, a sulfuric acid-based micro-etching agent, and a ferric chloride corrosive agent.

In a preferred embodiment, the high-porosity body is made of a substrate selected from the group consisting of copper, copper alloy, aluminum alloy, graphite, and silver.

To further understand the features and technical contents of the present invention, please refer to the following detailed description and drawings of the present invention. However, the drawings provided are only used for reference and description and are not used to limit the present invention.

The following is a specific embodiment to illustrate the implementation methods disclosed by the present invention. Technical personnel in this field can understand the advantages and effects of the present invention from the content disclosed in this specification. The present invention can be implemented or applied through other different specific embodiments. The details in this specification can also be modified and changed in various ways based on different viewpoints and applications without departing from the concept of the present invention. In addition, the drawings of the present invention are only for simple schematic illustrations and are not depicted according to actual sizes. Please note in advance. Moreover, the same or similar parts in the drawings are marked with the same reference numerals. The following implementation methods will further explain the relevant technical contents of the present invention in detail, but the disclosed contents are not intended to limit the scope of protection of the present invention. In addition, the term "or" used herein may include any one or more combinations of the associated listed items as appropriate.

[First embodiment]

Please refer to FIG. 1, which is one embodiment of the present invention. The present invention provides a two-phase immersion composite heat sink structure with a high-porosity solid body and a high-thermal-conductivity fin, which is used to contact a heat-generating element (heat source) immersed in a two-phase cooling liquid. As shown in FIG. 1, the two-phase immersion composite heat sink structure with a high-porosity solid body and a high-thermal-conductivity fin provided by the present invention includes a heat sink substrate 10, a plurality of high-thermal-conductivity fins 20, and more than one high-porosity solid body 30.

In this embodiment, the heat dissipation substrate 10 may be made of a material with high thermal conductivity, such as copper, copper alloy or aluminum alloy.

Specifically, the heat sink 10 may be plate-shaped and have a first surface 11 and a second surface 12 opposite to each other. The second surface 12 of the heat sink 10 is used to form contact with the heat generating element 800 immersed in the two-phase cooling liquid 900. This contact may be direct contact or indirect contact (thermal contact) through an intermediate layer.

Furthermore, the first surface 11 of the heat sink base 10 is connected to a plurality of high thermal conductivity fins 20, and the heat sink base 10 and the high thermal conductivity fins 20 can be integrally connected by metal injection molding (MIM) or skiving process, or connected by welding. The high thermal conductivity fins 20 can be made of metals such as copper, copper alloy, aluminum or aluminum alloy, and the high thermal conductivity fins 20 can be formed by bending, forging, extrusion, powder sintering, etc. Furthermore, the high thermal conductivity fin 20 may be a pin fin or a plate fin, and the height of the high thermal conductivity fin 20 is preferably greater than 3 mm, and the thermal conductivity of the high thermal conductivity fin 20 is greater than 300 W/m.K. In addition, the porosity of the high thermal conductivity fin 20 is less than 15%, because if it exceeds 15%, the thermal conductivity of the high thermal conductivity fin 20 will be too low and the mechanical strength will be insufficient.

Therefore, in order to further enhance the immersion heat dissipation effect, one or more high-porosity entities 30 are located on the first surface 11 of the heat dissipation substrate 10 and connected between the side walls of the adjacent high-thermal conductivity fins 20, or in other words, fill the gaps between the side walls of the adjacent high-thermal conductivity fins 20, and are arranged in a staggered manner. In addition, the predetermined volume ratio of the high-porosity entity 30 to the high-thermal conductivity fin 20 is greater than 0.25, and is preferably between 0.25 and 2.25. Furthermore, the porosity of the high-porosity entity 30 must be greater than the porosity of the high-thermal conductivity fin 20. Furthermore, the porosity of the high-porosity entity 30 can be greater than 20%, or even 70%. In addition, the height of the high-porosity body 30 is preferably greater than 1 mm, and the height of the high-porosity body 30 must be between 10% and 150% of the height of the high-thermal conductivity fin 20 .

In this embodiment, the high-porosity body 30 may be made of, but not limited to, a base material such as copper, copper alloy, aluminum alloy, graphite, silver, etc., and may be formed with a plurality of closed pores 301 and a plurality of open pores 302. Furthermore, the high-porosity body 30 may be formed by chemically corroding the base material with a chemical agent, and may be formed by chemically corroding with a phosphoric acid-based micro-etchant, a sulfuric acid-based micro-etchant, or a ferric chloride-based micro-etchant.

Furthermore, the high-porosity body 30 can be formed by sintering metal powder. In other words, the median particle size (D50) of the metal powder used to form the high-porosity body 30 is preferably between 30 microns and 800 microns, and a pore-forming agent is added to ensure that the porosity of the high-porosity body 30 can reach more than 20%. In addition, the closed pores 301 or open pores 302 of the high-porosity body 30 can be increased by chemical deposition, electroplating, or vapor deposition (physical or chemical vapor deposition).

Therefore, the present embodiment can achieve the improvement of vertical thermal conductivity and bubble nucleation points through the composite structure of high thermal conductivity fins and high porosity solid bodies, thereby effectively enhancing the overall immersion heat dissipation effect.

[Second embodiment]

Please refer to FIG. 2 , which is a second embodiment of the present invention. This embodiment is substantially the same as the first embodiment, and the differences are described as follows.

In this embodiment, a high thermal conductivity structure 40a is further included. Moreover, the high thermal conductivity structure 40a is a thermal conductivity structure having a thermal conductivity greater than 380W/m.K. Moreover, the high thermal conductivity structure 40a is bonded to the second surface 12 of the heat dissipation substrate 10, so that the second surface 12 of the heat dissipation substrate 10 forms indirect contact (thermal contact) with the heat generating element 800 immersed in the two-phase cooling liquid 900 through the high thermal conductivity structure 40a. In detail, the high thermal conductivity structure 40a can be bonded to the second surface 12 of the heat dissipation substrate 10 by welding, friction stir bonding (FSW), gluing, diffusion bonding, etc.

In this embodiment, the high thermal conductivity structure 40a can be a solid metal plate, which can be made of copper, copper alloy or aluminum alloy. In addition, the high thermal conductivity structure 40a can also be made of graphite with high thermal conductivity.

[Third Embodiment]

Please refer to FIG. 3 , which is a third embodiment of the present invention. This embodiment is substantially the same as the first and second embodiments, and the differences are described as follows.

In this embodiment, a vacuum sealed chamber 401 is formed inside the high thermal conductivity structure 40b, and the top wall 4011 and the bottom wall 4012 of the vacuum sealed chamber 401 may respectively form an upper sintered body 4013 and a lower sintered body 4014, and the vacuum sealed chamber 401 contains an appropriate amount of liquid, which may be water or acetone. Furthermore, the bottom surface of the high thermal conductivity structure 40b can be used to contact the heating element 800 immersed in the two-phase cooling liquid 900, so that the heating element 800 immersed in the two-phase cooling liquid 900 can not only absorb the heat generated by the heating element 800 through the two-phase cooling liquid 900, but also can contact and absorb the heat generated by the heating element 800 through the high thermal conductivity structure 40b, so that the liquid in the vacuum sealed cavity 401 is vaporized and evaporated into steam, which is dissipated to the heat dissipation base 1. 0 and quickly transfers the heat energy to the high thermal conductivity fins 20 and the high porosity entity 30 on the heat dissipation base 10, and uses the two-phase cooling liquid to absorb heat and vaporize to take away the heat energy absorbed by the high thermal conductivity fins 20 and the high porosity entity 30, while the steam in the vacuum sealed chamber 401 hands over the heat energy and condenses on the chamber top wall 4011 and then flows back to the chamber bottom wall 4012. Such a high-speed loop can quickly export the heat energy generated by the heating element 800, thereby further enhancing the overall immersion cooling effect.

In summary, the present invention provides a two-phase immersion composite heat dissipation structure with a high-porosity entity, which can at least be achieved through "a heat dissipation base", "a plurality of high thermal conductivity fins", "one or more high-porosity entities", "a heat dissipation base having a first surface and a second surface opposite to each other, the second surface of the heat dissipation base being used to form contact with a heat generating element immersed in a two-phase cooling liquid, and the first surface of the heat dissipation base being connected to a plurality of The invention discloses a technical solution of "a high thermal conductivity fin", "one or more high porosity entities are located on the first surface of the heat dissipation base and connected to the side walls of the adjacent high thermal conductivity fins and arranged in a staggered manner", "the high porosity entity forms a plurality of closed holes and a plurality of open holes", and "the predetermined volume ratio of the high porosity entity and the high thermal conductivity fin is greater than 0.25", thereby effectively enhancing the overall immersion heat dissipation effect.

The contents disclosed above are only preferred feasible embodiments of the present invention and are not intended to limit the scope of the patent application of the present invention. Therefore, all equivalent technical changes made using the contents of the specification and drawings of the present invention are included in the scope of the patent application of the present invention.

10: heat dissipation base 11: first surface 12: second surface 20: high thermal conductivity fin 30: high porosity solid 301: closed hole 302: open hole 40a, 40b: high thermal conductivity structure 401: vacuum sealed cavity 4011: cavity top wall 4012: cavity bottom wall 4013: upper sintered body 4014: lower sintered body 900: two-phase cooling liquid 800: heating element

FIG1 is a schematic side view of the structure of the first embodiment of the present invention.

FIG. 2 is a schematic side view of the structure of the second embodiment of the present invention.

FIG3 is a schematic side view of the structure of the third embodiment of the present invention.

10: Heat dissipation base

11: First surface

12: Second surface

20: Fins with high thermal conductivity

30: High porosity solid

301: Sealing hole

302: Opening hole

900: Two-phase cooling liquid

800:Heating element

Claims (10)

A two-phase immersion composite heat dissipation structure of a high-porosity entity and a high-thermal conductivity fin, comprising: a heat dissipation base, a plurality of high-thermal conductivity fins, and more than one high-porosity entity, wherein the heat dissipation base has a first surface and a second surface opposite to each other, the second surface of the heat dissipation base is used to form contact with a heat generating element immersed in a two-phase cooling liquid, the first surface of the heat dissipation base is connected to the plurality of high-thermal conductivity fins, and more than one high-porosity entity is located on the first surface of the heat dissipation base and connected between the side walls of the adjacent high-thermal conductivity fins and arranged in a staggered manner, and the high-porosity entity is formed with a plurality of closed holes and a plurality of open holes, and the predetermined volume ratio of the high-porosity entity to the high-thermal conductivity fins is greater than 0.25. A two-phase immersed composite heat dissipation structure having a high porosity body and a high thermal conductivity fin as described in claim 1, wherein the high thermal conductivity fin is made of a metal selected from the group consisting of copper, copper alloy, aluminum, and aluminum alloy. A two-phase immersed composite heat dissipation structure having a high porosity body and a high thermal conductivity fin as described in claim 1, wherein the high thermal conductivity is formed by one of bending, forging, extrusion, and powder sintering. A two-phase immersed composite heat dissipation structure comprising a solid body with high porosity and a fin with high thermal conductivity as described in claim 1, wherein the fin with high thermal conductivity is a needle-column fin or a sheet fin, and the thermal conductivity of the fin with high thermal conductivity is greater than 300 W/m.K. A two-phase immersed composite heat dissipation structure comprising a body with high porosity and a fin with high thermal conductivity as described in claim 1, wherein a predetermined volume ratio of the body with high porosity to the fin with high thermal conductivity is between 0.25 and 2.25. A two-phase immersed composite heat dissipation structure comprising a body with high porosity and a fin with high thermal conductivity as described in claim 1, wherein the porosity of the body with high porosity is greater than the porosity of the fin with high thermal conductivity, and the porosity of the body with high porosity is greater than 20% and less than 70%. A two-phase immersed composite heat dissipation structure comprising a body with high porosity and a fin with high thermal conductivity as described in claim 1, wherein the height of the body with high porosity is greater than 1 mm, and the height of the body with high porosity is between 10% and 150% of the height of the fin with high thermal conductivity. A two-phase immersed composite heat dissipation structure having a high-porosity body and a high-thermal conductivity fin as described in claim 1, wherein the high-porosity body is formed by sintering metal powder, and the median particle size (D50) of the metal powder used to form the high-porosity body is between 30 microns and 800 microns. A two-phase immersion composite heat sink structure comprising a high-porosity body and a high-thermal-conductivity fin as described in claim 1, wherein the high-porosity body is formed by chemically corroding a substrate with a chemical agent, and the chemical agent used to form the high-porosity body is one of a phosphoric acid-based micro-etching agent, a sulfuric acid-based micro-etching agent, and a ferric chloride corrosive agent. A two-phase immersion composite heat dissipation structure comprising a body with high porosity and a fin with high thermal conductivity as described in claim 1, wherein the body with high porosity is made of a substrate selected from the group consisting of copper, copper alloy, aluminum alloy, graphite, and silver.