A compact and lightweight heat dissipation device suitable for high heat flux density

Abstract

The present invention discloses a compact and lightweight heat dissipation device suitable for high heat flux density, belonging to the field of fluid heat transfer technology, including a cover body, a substrate, a composite material phase change plate and a temperature control panel are sequentially arranged at the opening of the cover body from the inside to the outside, the cover body and the substrate are enclosed to form a cover body cavity, a radiator inlet is arranged at the top of the cover body opposite to the substrate, and a plurality of radiator outlets are evenly arranged around the cover body; a rectifier plate and a jet spray combination plate are sequentially arranged from the inside to the outside in the cover body cavity near the radiator inlet, a plurality of jet holes are opened on the jet spray combination plate, and a plurality of metal balls are filled in the space between the jet spray combination plate and the substrate, and the fluid ejected from the jet hole can drive the metal balls to jump in the cover body cavity. The present invention combines spray and jet cooling technology, fully considers the behavior of bubbles in the phase change process, and avoids the deterioration of heat transfer and the occurrence of boiling criticality.

Description

Technical Field

[0001] The present invention belongs to the technical field of fluid heat transfer, and in particular relates to a compact and lightweight heat dissipation device suitable for high heat flux density. Background Art

[0002] At present, heat dissipation mainly includes air cooling, liquid cooling, and phase change cooling. However, with the development trend of high integration and miniaturization, the unit heat load has increased, and single-phase convection heat exchange can no longer meet the requirements of phase change cooling, which is prone to vapor phase aggregation, heat transfer deterioration, and then triggering boiling criticality. In general, some heat dissipation devices in the prior art have limited heat dissipation capacity, are prone to boiling crisis, and do not consider the timely discharge of the vapor phase. Summary of the invention

[0003] In view of this, the purpose of the present invention is to provide a compact and lightweight heat dissipation device suitable for high heat flux density, which combines spray and jet cooling technology, fully considers the bubble behavior in the phase change process, avoids heat transfer deterioration and boiling criticality.

[0004] In order to achieve the above object, the present invention provides the following technical solutions:

[0005] The present invention is a compact and lightweight heat dissipation device suitable for high heat flux density, comprising a cover body, wherein a substrate, a composite material phase change plate and a temperature control panel are sequentially arranged at an opening of the cover body from the inside to the outside, the cover body and the substrate are enclosed to form a cover body cavity, a radiator inlet is arranged at the top of the cover body opposite to the substrate, and a plurality of radiator outlets are evenly distributed around the cover body; a rectifier plate and a jet spray combination plate are sequentially arranged from the inside to the outside in the cover body cavity near the radiator inlet, a plurality of jet holes are opened on the jet spray combination plate, and a plurality of metal balls are filled in the space between the jet spray combination plate and the substrate, and the fluid sprayed from the jet holes can drive the metal balls to jump in the cover body cavity.

[0006] The beneficial effects of the present invention are:

[0007] The present invention is a compact and lightweight heat dissipation device suitable for high heat flux density. In order to avoid the problem of heat transfer deterioration and flow boiling instability caused by poor vapor phase flow, based on the study of pool boiling and the two-phase behavior of droplets impacting superheated surfaces, the overall structure of the cover body adopts a top-inlet and side-outlet, one-inlet and four-outlet method, and the outlet is inclined to ensure that the phase-change working medium is discharged in time after absorbing heat, avoiding local heat transfer deterioration and local burning.

[0008] The present invention designs a rectifying plate at the radiator inlet, which is located in the cavity above the jet spray combination plate and between the inlet, mainly for adjusting the flow direction of the inflowing working fluid and achieving approximately uniform distribution of the flow rate on the entire plane, so as to form a good jet and spray unit structure and obtain better surface temperature uniformity.

[0009] The present invention arranges a jet spray combination plate, thereby using a jet impact method, the fluid can directly impact the surface, the process is shortened, and a thinner boundary layer is formed near the stagnation point. The shortening of the boundary layer effectively enhances the heat exchange efficiency.

[0010] In the device of the present invention, by filling a plurality of metal balls in the space between the jet spray combination plate and the substrate, the fluid ejected from the jet hole can drive the metal balls to jump in the cover body cavity. During the jumping process, the metal balls can not only better transfer the heat on the substrate to the fluid in the inner cavity, but also accelerate the fluid disturbance in the cover body cavity, thereby achieving higher heat exchange capacity and better temperature uniformity.

[0011] Other advantages, objectives and features of the present invention will be described in the following description and will be apparent to those skilled in the art to some extent, or those skilled in the art may be taught from the practice of the present invention. The objectives and other advantages of the present invention may be realized and obtained through the following description. BRIEF DESCRIPTION OF THE DRAWINGS

[0012] In order to make the purpose, technical solution and beneficial effects of the present invention clearer, the present invention provides the following drawings for illustration:

[0013] Figure 1 It is a schematic structural diagram of the heat dissipation device of the present invention;

[0014] Figure 2 is a schematic structural diagram of a substrate of the present invention;

[0015] Figure 3 is a cross-sectional view of a substrate;

[0016] Figure 4 for Figure 3 A magnified view at point A;

[0017] Figure 5 is a schematic diagram of the structure of the cover;

[0018] Figure 6 It is a structural schematic diagram of the rectifier plate;

[0019] Figure 7 Schematic diagram of the structure of the jet spray combination plate.

[0020] The markings in the accompanying drawings are as follows: cover body 1, substrate 2, composite phase change plate 3, temperature control panel 4, cover body cavity 5, radiator inlet 6, radiator outlet 7, rectifier plate 8, jet spray combination plate 9, jet hole 10, metal ball 11, bottom plate 12, elastic plate 13, extrusion cavity 14, hollow column 15, blowing hole 16, micro conduction column 17, spray hole 18, pressure swirl nozzle 19, flexible metal 20, filter plate 21, cooling ring pipe 22, magnet 23, square hole 24. DETAILED DESCRIPTION

[0021] like Figures 1 to 7 As shown, the present invention is a compact and lightweight heat dissipation device suitable for high heat flux density, including a cover body 1. The cover body 1 is in a square cover shape as a whole. A substrate 2, a composite material phase change plate 3 and a temperature control panel 4 are sequentially fitted at the opening of the cover body 1 from the inside to the outside. The four sides of the substrate 2 are tightly fitted with the four sides of the cover body 1, so that a cover cavity 5 is formed between the cover body 1 and the substrate 2. A radiator inlet 6 is arranged on the top of the cover body 1 opposite to the substrate 2, and a fluid is introduced from the outside to the inside through the radiator inlet 6. A plurality of radiator outlets 7 are evenly arranged around the cover body 1, and the inlet and outlet are connected by a ferrule to ensure the sealing and reliability of the connection.

[0022] Among them, near the radiator inlet 6, a rectifying plate 8 and a jet spray assembly plate 9 are sequentially arranged from the inside to the outside in the cover body cavity 5, and the rectifying plate 8 and the jet spray assembly plate 9 are arranged at intervals. The distance between the jet spray assembly plate 9 and the substrate 2 is 10 mm. A plurality of jet holes 10 are opened on the jet spray assembly plate 9, and a plurality of metal balls 11 are filled in the space between the jet spray assembly plate 9 and the substrate 2. The fluid ejected from the jet holes 10 can drive the metal balls 11 to jump in the cover body cavity 5. By filling a plurality of metal balls 11 in the space between the jet spray assembly plate 9 and the substrate 2, the fluid ejected from the jet holes 10 can drive the metal balls 11 to jump in the cover body cavity 5. During the jumping process, the metal balls 11 can not only better transfer the heat on the substrate 2 to the fluid in the inner cavity, but also accelerate the fluid disturbance in the cover body cavity 5, thereby achieving a higher heat exchange capacity and better temperature uniformity.

[0023] In this embodiment, the substrate 2 includes a bottom plate 12 and an elastic plate 13 fixed on the bottom plate 12. The elastic plate 13 can be made of a metal sheet material. The elastic plate 13 faces the side where the cover body 1 is located. The bottom plate 12 and the elastic plate 13 are separated vertically to form an extrusion cavity 14. A plurality of hollow columns 15 connected to the extrusion cavity 14 are formed on the elastic plate 13. A plurality of blowing holes 16 are opened at the root of the hollow column 15. The metal ball 11 can squeeze the extrusion cavity 14 when jumping, and squeeze the internal air outward from the blowing holes 16, so as to disturb the air flow on the surface of the substrate 2. The present invention arranges a microstructure on the surface of the substrate 2. Through the surface microstructure, the surface temperature can be reduced, and the critical heat flux density can be increased to increase the disturbance of the fluid, thereby achieving a higher heat exchange capacity and better temperature uniformity. Considering the power consumption of the system, the two-phase boiling heat transfer has a greater heat exchange capacity, and the working fluid flow required to achieve the predetermined heat dissipation capacity is smaller, that is, the corresponding power consumption is smaller. Therefore, fluid disturbance and surface strengthening structure are added to the substrate, so as to achieve higher heat transfer capacity and better temperature uniformity under lower power consumption. The surface strengthening structure hollow pillar 15 is a micro-pillar array with a diameter of 0.5 mm, a height of 0.8 mm, and a spacing of 1 mm.

[0024] In this embodiment, a plurality of micro-conductive columns 17 are arranged in an array on the base plate 12, and the plurality of micro-conductive columns 17 correspond to the hollow columns 15 one by one. The lower ends of the micro-conductive columns 17 are fixedly connected to the base plate 12, and the upper ends of the micro-conductive columns 17 extend axially toward the hollow columns 15 to support the inner top of the hollow columns 15. By arranging the micro-conductive columns 17, not only can heat be conducted through the micro-conductive columns 17, but also the hollow columns 15 can be supported, thereby ensuring the basic shape of the substrate 2 even under the continuous impact of the metal balls 11.

[0025] In this embodiment, a plurality of square holes 24 with a side length of 1 mm and a spacing of 1.15 mm are provided on the rectifying plate 8. The rectifying plate 8 is designed at the radiator inlet 6, which is located in the cavity above the jet spray combination plate 9 and between the inlet, mainly to adjust the flow direction of the inflowing working fluid and to achieve approximately uniform distribution of the flow rate in the entire plane, so as to form a good jet and spray unit structure and obtain better surface temperature uniformity.

[0026] In this embodiment, a plurality of spray holes 18 are arranged in an array on the jet spray assembly plate 9, and a pressure swirl nozzle 19 is installed in the spray hole 18, and the pressure swirl nozzle 19 sprays the fluid directly on the substrate 2. The present invention adopts a jet impact method, so that the fluid can directly impact the surface, the process is shortened, and a thinner boundary layer is formed near the stagnation point. The shortening of the boundary layer effectively enhances the heat exchange efficiency. Therefore, jet impact cooling is suitable for environments with larger heat flux density, but its cooling unevenness is more prominent, and local heat transfer deterioration is prone to occur. Spray cooling is a cooling method in which the cooling medium is atomized and sprayed onto a high-temperature surface, and single-phase or two-phase heat exchange is performed on the hot surface to take away heat. It can achieve a higher heat exchange rate in a smaller heat exchange area and can exchange heat evenly. Its greatest advantage is uniform cooling and high heat flux density, which can well balance the contradiction between heat exchange capacity and heat exchange uniformity. Therefore, the combination of the two is realized by the cross-row coupling mode. By setting a circular matrix jet and an array spray hole 18, the solid conical nozzle in the pressure swirl nozzle 19 is selected for spraying. The total surface area of ​​the liquid is significantly improved during the spraying process, thereby greatly enhancing the heat transfer process. The pressure swirl nozzle 19 is a nozzle through which the fluid is accelerated through the swirl plate and enters the central swirl chamber. In the swirl chamber, the rotating liquid is squeezed to the wall surface, and an air column is formed in the center of the fluid. Then, the liquid is ejected from the nozzle in an unstable film state and broken into droplets. The cooling capacity of a single hole is limited, so an array arrangement is adopted, which can not only meet the transient high power, but also obtain a more uniform surface temperature distribution. 44 arrays of distributed jet holes 10 and 33 array spray nozzles are arranged on the jet and spray combination plate, and the specific structure is shown in the figure. The apertures of the jet holes 10 and the spray nozzles are both 0.5mm, the spacing is 6mm, and the jet height, that is, the distance from the jet and spray combination plate to the substrate 2 is 10mm.

[0027] In this embodiment, the composite phase change plate 3 is made of thermal conductive silicone grease, foam metal and expanded graphite, and the outer side of the composite phase change plate 3 is wrapped with flexible metal 20. The large phase change latent heat of the composite phase change material is used to quickly absorb a large amount of heat emitted by the heat source, while its own temperature fluctuates only slightly. When the temperature of the heat source is too high, the energy storage layer plays a role of absorbing heat, and when the upper surface temperature is too low due to the heat dissipation system, the energy storage layer plays a role of buffering and heat preservation. Figure 6 The composite phase change material is wrapped by the aluminum-based flexible metal 20, which is well compatible with the current heat source, and the contact thermal resistance is reduced through the thermal conductive silicone grease. The thermal conductivity is greatly improved through the foam metal and expanded graphite.

[0028] In this embodiment, the radiator outlet 7 is arranged to be inclined upward from the inside to the outside, and a filter plate 21 is provided at the inner end of the radiator outlet 7 to prevent the metal balls 11 from overflowing.

[0029] In this embodiment, the edge of the jet spray assembly plate 9 is also provided with a jet hole 10, and a cooling ring tube 22 is provided on the outer side of the cover body 1. A magnet 23 is installed on the inner wall of the cooling ring tube 22 facing the side where the cover body 1 is located, and the magnet 23 can attract the nearby metal balls 11 to the inner side of the cover body 1. During the continuous jumping process of the metal balls 11, some metal balls 11 that have conducted heat can be adsorbed on the inner wall of the cover body 1 where the magnet 23 is located. The metal balls 11 can be quickly cooled by the cooling ring tube 22, and then the metal balls 11 fall under the action of the jet or the collision of other metal balls 11, and enter the cavity again to disturb the fluid and conduct heat, which can improve the heat dissipation efficiency of the device.

[0030] Finally, it should be noted that the above preferred embodiments are only used to illustrate the technical solutions of the present invention rather than to limit it. Although the present invention has been described in detail through the above preferred embodiments, those skilled in the art should understand that various changes can be made in form and details without departing from the scope defined by the claims of the present invention.

Claims

1. A compact and lightweight heat dissipation device suitable for high heat flux density, characterized in that: The invention comprises a cover body, wherein a substrate, a composite material phase change plate and a temperature control panel are sequentially arranged at the opening of the cover body from the inside to the outside, the cover body and the substrate are enclosed to form a cover body cavity, a radiator inlet is arranged at the top of the cover body opposite to the substrate, and a plurality of radiator outlets are evenly arranged around the cover body; a rectifying plate and a jet spray combination plate are sequentially arranged from the inside to the outside in the cover body cavity near the radiator inlet, a plurality of jet holes are opened on the jet spray combination plate, a plurality of metal balls are filled in the space between the jet spray combination plate and the substrate, and the fluid ejected from the jet holes can drive the metal balls to jump in the cover body cavity; the substrate comprises a bottom plate and an elastic plate fixed on the bottom plate, the elastic plate faces the side where the cover body is located, an extrusion cavity is formed between the bottom plate and the elastic plate in the vertical direction, a plurality of hollow columns connected with the extrusion cavity are formed on the elastic plate, and a plurality of blowing holes are opened at the root of the hollow columns.

2. A compact and lightweight heat dissipation device suitable for high heat flux density according to claim 1, characterized in that: A plurality of micro-conductive columns are arranged in an array on the bottom plate, and the plurality of micro-conductive columns correspond to the hollow columns one by one. The lower ends of the micro-conductive columns are fixedly connected to the bottom plate, and the upper ends of the micro-conductive columns extend toward the axial direction of the hollow columns to support the inner top of the hollow columns.

3. A compact and lightweight heat dissipation device suitable for high heat flux density according to claim 1, characterized in that: The rectifier plate is provided with a plurality of square holes with a side length of 1 mm and a spacing of 1.15 mm.

4. A compact and lightweight heat dissipation device suitable for high heat flux density according to claim 3, characterized in that: The jet spray combination plate is also provided with a plurality of spray holes in an array, and pressure swirl nozzles are installed in the spray holes. The pressure swirl nozzles are directly spraying the fluid toward the substrate.

5. A compact and lightweight heat dissipation device suitable for high heat flux density according to claim 4, characterized in that: The composite material phase change plate is composited by heat-conducting silicone grease, foam metal and expanded graphite.

6. A compact and lightweight heat dissipation device suitable for high heat flux density according to claim 5, characterized in that: The outer side of the composite phase change plate is wrapped with flexible metal.

7. A compact and lightweight heat dissipation device suitable for high heat flux density according to claim 1, characterized in that: The radiator outlet is arranged obliquely upward from the inside to the outside, and a filter plate is provided at the inner end of the radiator outlet.

8. A compact and lightweight heat dissipation device suitable for high heat flux density according to any one of claims 1 to 7, characterized in that: The edge of the jet spray combination plate is also provided with jet holes, the outer side of the cover body is provided with a cooling ring tube, and the inner wall of the cooling ring tube is provided with a magnet on the side facing the cover body, and the magnet can attract nearby metal balls to the inner side of the cover body.

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