AU2021294898A1

AU2021294898A1 - Heat dissipation and cooling apparatus for high heat flux heating element

Info

Publication number: AU2021294898A1
Application number: AU2021294898A
Authority: AU
Inventors: Kaijun DONG; Zhenhua Shao; Lin SU
Original assignee: Guangzhou Institute of Energy Conversion of CAS
Current assignee: Guangzhou Institute of Energy Conversion of CAS
Priority date: 2020-09-07
Filing date: 2021-07-29
Publication date: 2022-11-03
Also published as: WO2021259385A1; CN112040741A

Abstract

A radiation cooling device for a high-heat-flux heat generating element. The device is composed of a cold plate, a first thermal conductive silica gel layer, a graphene thermal conduction layer, a second thermal conductive silica gel layer and a heat generating element, wherein the graphene thermal conduction layer is composed of a metal housing, several pieces of graphene and several metal sheets; the graphene and the metal sheets are successively stacked from left to right, and are all vertically arranged between the cold plate and the heat generating element; and thermal conductive silica gel is filled between the cold plate and the graphene thermal conduction layer, and between the graphene thermal conduction layer and the heat generating element. Heat generated by the heat generating element is conducted, by using the ultrahigh thermal conductivity of the graphene in the plane direction, from the heat generating element, which has a very small surface area, to the cold plate, which has a relatively large area, and the thermal conductive silica gel layers can also effectively reduce thermal contact resistance during a heat transfer process, such that the heat generated by the heat generating element can be rapidly dissipated to the external environment by means of a cooling medium inside the cold plate, thereby greatly improving the radiation efficiency.

Description

HEAT DISSIPATION AND COOLING APPARATUS FOR HIGH HEAT FLUX HEATING ELEMENT TECHNICAL FIELD

[0001] The present invention relates to the field of heat dissipation and cooling technologies, and more particularly, to a heat dissipation and cooling apparatus for a high heat flux heating element.

BACKGROUND

[0002] The rapid development of a new generation of information technology has put forward higher computing requirements for electronic information devices; the number and package density of transistors in chips such as high-performance CPU/GPU have increased rapidly, resulting in rapid increase in heating capacity. In a case where the size of the heating element is basically unchanged or even reduced, heat flux density on the surface of the heating element increases sharply. However, the existing heat dissipation and cooling technologies have limited heat dissipation capacity, heat extraction of the heat flux density cannot meet the heat dissipation and cooling requirements of the high heat flux heating element, and the problem of overheating and shutdown frequently occurs.

[0003] Graphene has a very good thermally conductive performance, and has thermal conductivity as high as 5,300 W/m*K, which is the material with the highest thermal conductivity so far, and is suitable for heat dissipation and cooling of elements with high heat flux density. However, thermal conductivity of graphene is anisotropic, and its thermal conductivity in the vertical direction is much lower than the thermal conductivity in the plane direction.

SUMMARY

[0004] In order to overcome the above-described deficiencies of the existing technology, the present invention proposes a heat dissipation and cooling apparatus for a high heat flux heating element. The apparatus fully utilizes ultra-high thermal conductivity of graphene along the plane direction, to conduct heating capacity generated by the heating element from a heating element with a smaller surface area to a cold plate with an area larger than the area of the heating element; meanwhile, a thermally conductive silica gel layer may effectively reduce contact thermal resistance during the heat transfer process; and heating capacity generated by the heating element may be quickly dissipated to the external environment through a cooling medium inside the cold plate, so that heat dissipation efficiency is greatly improved.

[0005] In order to achieve the above-described objective, the technical solution adopted in the present invention is:

[0006] A heat dissipation and cooling apparatus for a high heat flux heating element, including a cold plate, a first thermally conductive silica gel layer, a graphene thermally conductive layer, a second thermally conductive silica gel layer and a heating element, which are arranged in sequence from top to bottom; the graphene thermally conductive layer is composed of a metal shell, a plurality of layers of graphene and a plurality of metal flakes; the layers of graphene and the metal flakes are stacked in sequence from left to right, and are all placed vertically between the cold plate and the heating element; and thermally conductive silica gel is filled between the cold plate and the graphene thermally conductive layer, and between the graphene thermally conductive layer and the heating element.

[0007] Preferably, the area of the lower surface of the cold plate is equal to the area of the upper surface of the graphene thermally conductive layer; and the area of the lower surface of the graphene thermally conductive layer is equal to the area of the upper surface of the heating element.

[0008] Preferably, the area of the upper surface of the graphene thermally conductive layer is larger than the area of the lower surface of the graphene thermally conductive layer.

[0009] Preferably, the length of the upper surface of the graphene thermally conductive layer in the direction along which the layers of graphene and the metal flakes are stacked in sequence is equal to the length of the lower surface in the direction along which the layers of graphene and the metal flakes are stacked in sequence.

[0010] Preferably, the shape of the graphene thermally conductive layer is a trapezoid or a stepped shape that is large at the top and small at the bottom.

[0011] As compared with the existing technology, advantageous effects of the present invention are:

[0012] 1. The graphene thermally conductive layer is composed of a metal shell, a plurality of layers of graphene and a plurality of metal flakes; the layers of graphene and the metal flakes are stacked in sequence from left to right, and are placed vertically between the cold plate and the heating element; ultra-high thermal conductivity of graphene along the plane direction is fully utilized, and the thermally conductive heat flux of the graphene thermally conductive layer is greatly improved.

[0013] 2. The graphene thermally conductive layer conducts heating capacity generated by the heating element from the heating element with a small surface area to the cold plate with a surface area larger than the surface area of the heating element; meanwhile, the thermally conductive silica gel layer can effectively reduce contact thermal resistance in the heat transfer process; the heating capacity generated by the heating element can be quickly dissipated to the external environment through the cooling medium inside the cold plate; and the heat dissipation efficiency is greatly improved.

BRIEF DESCRIPTION OF THE DRAWINGS

[0014] FIG. 1 is a front view of a heat dissipation and cooling apparatus for a high heat flux heating element according to Embodiment I.

[0015] FIG. 2 is a side view of a heat dissipation and cooling apparatus for a high heat flux heating element according to Embodiment I.

[0016] FIG. 3 is an appearance diagram of a graphene thermally conductive layer whose outer shape is a trapezoid body according to Embodiment I.

[0017] FIG. 4 is a side view of a heat dissipation and cooling apparatus for a high heat flux heating element according to Embodiment II.

[0018] FIG. 5 is an appearance diagram of the graphene thermally conductive layer whose outer shape is a stepped body according to Embodiment II.

[0019] Description of reference signs: 1-cold plate; 2-first thermally conductive silica gel layer; 3-graphene thermally conductive layer; 30-metal shell; 31-graphene; 32-metal flake; 4-second thermally conductive silica gel layer; 5-heating element.

DETAILED DESCRIPTION

[0020] In order to make objectives, technical details and advantageous effects of the present invention apparent, the technical solutions in the embodiments of the present invention will be described in a clearly and fully understandable way in connection with the drawings in the embodiments of the present invention. It is obvious that the described embodiments are just a part but not all of the embodiments of the present invention.

[0021] In the description of the present invention, it should be understood that, the terms "first" and "second" are only used for description purposes, and cannot be understood as indicating relative importance or implicitly indicating the number of indicated technical features. Thus, a feature defined as "first" or "second" may expressly or implicitly include one or more of that feature. In the description of the present invention, unless otherwise specified, "a plurality of' refers to two or more.

[0022] Embodiment I

[0023] As shown in FIG. 1, FIG. 2, and FIG. 3, a heat dissipation and cooling apparatus for a high heat flux heating element according to this embodiment includes a cold plate 1, a first thermally conductive silica gel layer 2, a graphene thermally conductive layer 3 and a second thermally conductive silica gel layer 4.

[0024] The cold plate 1, the first thermally conductive silica gel layer 2, the graphene thermally conductive layer 3, and the second thermally conductive silica gel layer 4 are arranged in sequence on the heating element 5 from top to bottom.

[0025] The graphene thermally conductive layer 3 is mainly composed of a metal shell 30, a plurality of layers of graphene 31 and a plurality of metal flakes 32; the layers of graphene 31 and the metal flakes 32 are stacked in sequence from left to right, and are vertically placed between the cold plate 1 and the heating element 5.

[0026] Preferably, the area of the lower surface of the cold plate 1 is equal to the area of the upper surface of the graphene thermally conductive layer 3; and the area of the lower surface of the graphene thermally conductive layer 3 is equal to the area of the upper surface of the heating element 5.

[0027] In order to further improve heat dissipation efficiency, the area of the upper surface of the graphene thermally conductive layer 3 needs to be greater than the area of the lower surface of the graphene thermally conductive layer 3. To this end, in this embodiment, the graphene 31 and the metal flake 32 are trapezoidal sheets that are large at the top and small at the bottom, and are laminated in sequence to form a trapezoidal body. It is easy to understand that, since the layers of graphene 31 and the metal flakes 32 are stacked vertically in sequence, the length of the upper surface of the graphene thermally conductive layer 3 along the stacking direction is equal to the length of the lower surface along the stacking direction.

[0028] During operation, heating capacity generated by the heating element 5 is transferred to the graphene thermally conductive layer 3 whose outer shape is a trapezoid body through the second thermally conductive silica gel layer 4; the graphene thermally conductive layer 3 whose outer shape is a trapezoid body then transfers the heating capacity to the first thermally conductive silica gel layer 2; the first thermally conductive silica gel layer 2 then transfers the heating capacity to the cold plate 1; and heating capacity absorbed by the cold plate 1 is quickly dissipated to the surrounding environment through a cooling medium in a forced convection manner, thereby implementing heat dissipation and cooling of the heating element 5.

[0029] Embodiment II

[0030] As shown in FIG. 4 and FIG. 5, the heat dissipation and cooling apparatus for the high heat flux heating element according to this embodiment differs from Embodiment I in that the graphene layer 31 and the metal flake 32 are stepped sheets that are large at the top and small at the bottom, with both sides being a stepped shape.

[0031] During operation, heating capacity generated by the heating element 5 is transferred to the graphene thermally conductive layer 3 whose outer shape is a stepped body through the second thermally conductive silica gel layer 4; then the graphene thermally conductive layer 3 whose outer shape is a stepped body transfers the heating capacity to the first thermally conductive silica gel layer 2; the first thermally conductive silica gel layer 2 then transfers the heating capacity to the cold plate 1; and heating capacity absorbed by the cold plate 1 is quickly dissipated to the surrounding environment through a cooling medium in a forced convection manner, thereby implementing heat dissipation and cooling of the heating element 5.

[0032] The above-described embodiments are only intended to illustrate the technical concept and characteristics of the present invention, and the purpose thereof is to enable those ordinarily skilled in the art to understand the content of the present invention and implement the same accordingly, and not to limit the protection scope of the present invention. All equivalent changes or modifications made according to the essence of the present invention shall be included within the protection scope of the present invention.

Claims

CLAIMS What is claimed is: 1. A heat dissipation and cooling apparatus for a high heat flux heating element, comprising: a cold plate, a first thermally conductive silica gel layer, a graphene thermally conductive layer, a second thermally conductive silica gel layer and a heating element, which are arranged in sequence from top to bottom; the graphene thermally conductive layer is composed of a metal shell, a plurality of layers of graphene and a plurality of metal flakes; the layers of graphene and the metal flakes are stacked in sequence from left to right, and are all placed vertically between the cold plate and the heating element; and thermally conductive silica gel is filled between the cold plate and the graphene thermally conductive layer, and between the graphene thermally conductive layer and the heating element.
2. The heat dissipation and cooling apparatus for the high heat flux heating element according to claim 1, wherein the area of the lower surface of the cold plate is equal to the area of the upper surface of the graphene thermally conductive layer; and the area of the lower surface of the graphene thermally conductive layer is equal to the area of the upper surface of the heating element.
3. The heat dissipation and cooling apparatus for the high heat flux heating element according to claim 1, wherein the area of the upper surface of the graphene thermally conductive layer is larger than the area of the lower surface of the graphene thermally conductive layer.
4. The heat dissipation and cooling apparatus for the high heat flux heating element according to claim 3, wherein the length of the upper surface of the graphene thermally conductive layer in the direction along which the layers of graphene and the metal flakes are stacked in sequence is equal to the length of the lower surface in the direction along which the layers of graphene and the metal flakes are stacked in sequence.
5. The heat dissipation and cooling apparatus for the high heat flux heating element according to claim 4, wherein a shape of the graphene thermally conductive layer is a trapezoid or a stepped shape that is large at the top and small at the bottom.