Enhanced heat exchange liquid cooling radiator and preparation method thereof

Abstract

The invention belongs to the technical field of liquid cooling heat dissipation, and relates to an enhanced heat exchange liquid cooling radiator and a preparation method thereof.The enhanced heat exchange liquid cooling radiator comprises a heat dissipation substrate and a heat dissipation assembly, the heat dissipation assembly comprises heat dissipation columns and turbulent flow elements, the heat dissipation columns are cylinders and are distributed on the second surface of the heat dissipation substrate in a staggered mode, and the turbulent flow elements are distributed on the second surface of the heat dissipation substrate; and the turbulent flow elements are distributed on the surface of the heat dissipation column at intervals. Through the unique design of the heat dissipation assembly, the heat exchange performance is remarkably improved. The turbulent flow elements are additionally arranged on the surfaces of the heat dissipation columns, vortex flow is generated in a boundary layer area close to the cylindrical side face through the innovative design, and heat exchange between fluids is effectively promoted. The design not only reduces the thermal resistance of the viscous bottom layer, but also greatly enhances the convective heat transfer effect, thereby greatly improving the heat dissipation performance of the radiator. The breakthrough design thought brings brand new technical innovation to the field of liquid cooling heat dissipation.

Description

Technical Field

[0001] The invention belongs to the technical field of liquid cooling and heat dissipation, and relates to an enhanced heat exchange liquid cooling radiator and a preparation method thereof. Background Art

[0002] As power electronic equipment develops towards high integration and high power density, the heat loss of related semiconductor devices is also increasing rapidly. As the heat loss increases, higher requirements are placed on the heat dissipation performance of power electronic equipment.

[0003] Currently, the most widely used is the cold plate type liquid cooling radiator. This cooling method without direct contact with the heating element ensures its safety and reliability during operation, and its efficiency of heat exchange using the liquid phase is much higher than that of the air-cooled radiator using air for heat exchange. In order to improve the heat exchange performance of the radiator, it is usually achieved by adding a cylindrical needle structure to the substrate of the cold plate type liquid cooling, and increasing the number of overall needle structures by reducing the needle gap or reducing the needle radius to increase the heat exchange area. However, while this method improves the heat exchange efficiency, it will also significantly increase the flow resistance of the radiator, thereby significantly increasing the operating cost of the cooling system.

[0004] The internal structure of the liquid cooling radiator has a great influence on the heat conduction efficiency. The best design can maximize the heat exchange area between the liquid cooling plate and hot components such as the CPU or GPU, thereby ensuring efficient heat transfer. Traditional liquid cooling radiators are generally made by casting, welding, machining and other processing methods, and it is difficult or impossible to achieve micro-structure design inside the cold plate. However, these micro-structure designs can achieve better heat dissipation performance by increasing the heat exchange area of ​​the liquid cooling plate, affecting the flow pattern of the liquid cooling medium, and reducing the flow resistance. Summary of the invention

[0005] In view of this, an object of the present invention is to provide a heat exchange enhanced liquid-cooled radiator and a preparation method thereof, so as to significantly improve the heat exchange performance of the radiator.

[0006] In order to achieve the above object, the present invention provides the following technical solutions:

[0007] A heat exchange enhanced liquid-cooled radiator comprises a heat dissipation substrate and a heat dissipation component, wherein the heat dissipation substrate comprises a first surface and a second surface arranged opposite to each other, the first surface is connected to a heat generating device or component, the heat dissipation component is arranged on the second surface of the heat exchange enhanced liquid-cooled radiator, and a heat dissipation flow channel for accommodating the heat dissipation component is provided on one side of the second surface, the heat dissipation component comprises heat dissipation columns and spoiler elements, the heat dissipation columns are cylindrical and are distributed in a cross-row form on the second surface of the heat dissipation substrate, and the spoiler elements are distributed at intervals on the surface of the heat dissipation columns.

[0008] Furthermore, the heat dissipation columns are divided into rows arranged along the flow direction of the liquid cooling medium of the radiator and columns arranged along the width direction of the radiator, and the row spacing a is 0.9mm≤a≤5.5mm, the column spacing b is 0.9mm≤b≤5.5mm, and 0.8d≤a, b≤2.2d, where d is the diameter of the heat dissipation column.

[0009] Furthermore, the spoiler is a square column microstructure and is distributed on the surface of the heat dissipation column at a certain interval along the circumferential direction. The protrusion width j and protrusion height k of the spoiler, the width L of the radiator flow channel, the column spacing b of the heat dissipation column, the height h of the heat dissipation column and the diameter d of the heat dissipation column satisfy the following relationship:

[0010] 0.5≤k / j≤5

[0011]

[0012] The υ is the kinematic viscosity of the coolant in the radiator flow channel, and Q is the volume flow rate of the coolant.

[0013] Furthermore, the center distance s between two adjacent spoiler elements satisfies the following formula:

[0014] s / k=9.9(k / j) -0.345 .

[0015] Furthermore, the height h of the heat dissipation column is 3mm≤h≤8mm, and the diameter d of the heat dissipation column is 0.5mm≤d≤2.5mm.

[0016] Furthermore, the thickness p of the heat dissipation substrate is between 0.8 mm and 4 mm.

[0017] Furthermore, the heat dissipation column is a cylinder, and the front stagnation point of the heat dissipation column is set to an azimuth angle of 0°, and the azimuth angle of the distribution area of ​​the spoiler element on the heat dissipation column is -130°≤φ≤130°.

[0018] A method for preparing an enhanced heat exchange radiator comprises the following steps:

[0019] S1. Design a product model based on the enhanced heat exchange liquid cooling radiator;

[0020] S2. Slice the designed product model, set the layer thickness and printing process parameters, and obtain a product printing process parameter package suitable for pure copper laser selective melting 3D printing process;

[0021] S3. The product printing process parameter package is imported into the laser selective melting 3D printer. The laser selective melting 3D printer controls the working state of the laser selective melting 3D printer according to the product printing process parameter package, and prepares the blank by melting the pure copper metal powder layer by layer;

[0022] S4. heat treating the blank to obtain a product;

[0023] S5. Perform a surface treatment process on the heat-treated product to obtain a product that can be actually used.

[0024] Furthermore, the particle size of the pure copper metal powder is in the range of 15-53 μm, the oxygen content is lower than 300 ppm, and the powder morphology is nearly spherical.

[0025] Furthermore, the printing process parameters include laser power, scanning speed and scanning spacing, and the laser power is between 600-800w, the scanning speed is between 200-600mm / s, and the scanning spacing is between 70μm-90μm.

[0026] The beneficial effects of the present invention are:

[0027] First of all, the present invention achieves a significant improvement in heat exchange performance through a unique heat dissipation component design. By adding a spoiler element to the surface of the heat dissipation column, this innovative design generates a vortex flow in the boundary layer area near the side of the cylinder, effectively promoting heat exchange between fluids. This design not only reduces the thermal resistance of the viscous bottom layer, but also greatly enhances the convective heat transfer effect, thereby greatly improving the heat dissipation performance of the radiator. This groundbreaking design idea has brought a new technological innovation to the field of liquid cooling.

[0028] Secondly, the present invention provides a scientific and efficient method for determining radiator parameters. Through precise relationship formulas, various parameter dimensions of the radiator, such as row spacing, column spacing, spoiler element distribution, etc., can be quickly calculated, which greatly shortens the design cycle of the liquid cooling radiator and improves the design efficiency. At the same time, this parametric design method also ensures the stability and reliability of the radiator performance, providing strong support for mass production.

[0029] Finally, the preparation method of the present invention adopts advanced laser selective melting 3D printing technology to achieve high-precision printing and preparation of the microstructure of the spoiler element on the heat dissipation column of the radiator. This technology not only ensures the manufacturing accuracy and surface quality of the radiator, but also makes the structure of the radiator more complex and diversified. In addition, by optimizing the printing process parameters, such as laser power, scanning speed, and scanning spacing, the manufacturing quality and performance of the radiator are further improved. This innovative preparation method not only reduces production costs, but also greatly improves the market competitiveness of the radiator, injecting new vitality into the development of the field of liquid cooling and heat dissipation.

[0030] Other advantages, objectives and features of the present invention will be described in the following description to some extent, and to some extent, will be obvious to those skilled in the art based on the following examination and study, or can be taught from the practice of the present invention. The objectives and other advantages of the present invention can be realized and obtained through the following description. BRIEF DESCRIPTION OF THE DRAWINGS

[0031] In order to make the purpose, technical solutions and advantages of the present invention more clear, the present invention will be described in detail below in conjunction with the accompanying drawings, wherein:

[0032] Figure 1 It is a structural schematic diagram of an enhanced heat exchange liquid cooling radiator in an embodiment;

[0033] Figure 2 A side view of an enhanced heat exchange liquid cooling radiator in an embodiment;

[0034] Figure 3 Schematic diagram of arrangement of heat dissipation columns on a heat dissipation substrate in an embodiment;

[0035] Figure 4 Schematic diagram of the distribution of spoiler elements on the heat dissipation column in the embodiment;

[0036] Figure 5 It is a structural schematic diagram of the heat dissipation column in the embodiment;

[0037] Figure 6 Schematic diagram of arrangement of spoiler elements on heat dissipation columns in an embodiment.

[0038] Reference numerals: heat dissipation substrate 1 , heat dissipation assembly 2 , heat dissipation column 21 , spoiler 22 . DETAILED DESCRIPTION

[0039] The following describes the embodiments of the present invention by specific examples, and those skilled in the art can easily understand other advantages and effects of the present invention from the contents disclosed in this specification. The present invention can also be implemented or applied through other different specific embodiments, and the details in this specification can also be modified or changed in various ways based on different viewpoints and applications without departing from the spirit of the present invention. It should be noted that the illustrations provided in the following embodiments only illustrate the basic concept of the present invention in a schematic manner, and the following embodiments and features in the embodiments can be combined with each other without conflict.

[0040] Among them, the drawings are only used for illustrative explanations, and they only represent schematic diagrams rather than actual pictures, and should not be understood as limitations on the present invention. In order to better illustrate the embodiments of the present invention, some parts of the drawings may be omitted, enlarged or reduced, and do not represent the size of actual products. For those skilled in the art, it is understandable that some well-known structures and their descriptions in the drawings may be omitted.

[0041] The same or similar numbers in the drawings of the embodiments of the present invention correspond to the same or similar parts; in the description of the present invention, it should be understood that if the terms "upper", "lower", "left", "right", "front", "rear", etc. indicate the orientation or position relationship, they are based on the orientation or position relationship shown in the drawings, which is 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 operate in a specific orientation. Therefore, the terms describing the position relationship in the drawings are only used for illustrative purposes and cannot be understood as limiting the present invention. For ordinary technicians in this field, the specific meanings of the above terms can be understood according to specific circumstances.

[0042] See also Figure 1 to Figure 6 , is an enhanced heat exchange liquid cooling radiator, designed based on a cold plate radiator, comprising a heat dissipation substrate 1 and a heat dissipation component 2, wherein the heat dissipation substrate 1 comprises a first surface and a second surface arranged opposite to each other, wherein the first surface is connected to a heat generating device or component, and the heat dissipation component 2 is arranged on the second surface of the enhanced heat exchange liquid cooling radiator, and a heat dissipation channel for accommodating the heat dissipation component 2 is provided on one side of the second surface, wherein the heat dissipation component comprises a heat dissipation column 21 and a spoiler element 22, wherein the heat dissipation column is a cylinder and is distributed in a cross-row form on the second surface of the heat dissipation substrate, and the spoiler element is a column structure and is distributed on the surface of the heat dissipation column at a certain interval;

[0043] Among them, the protrusion width j of the spoiler, the protrusion height k, the center distance s of the spoiler, the width L of the radiator flow channel, the row spacing a of the heat dissipation column, the column spacing b of the heat dissipation column, the diameter d of the heat dissipation column and the height h of the heat dissipation column satisfy the following relationship:

[0044] and

[0045] s / j=9.9(k / j) -0.345

[0046]

[0047] Where υ is the kinematic viscosity of the coolant and Q is the volume flow rate of the coolant.

[0048] Preferably, the thickness p of the heat dissipation substrate is between 0.8 mm and 4 mm. If the thickness is too thin, the heat diffusion and structural strength of the heat dissipation substrate will be affected. If the thickness is too thick, the diffusion thermal resistance will increase, affecting the heat conduction.

[0049] Preferably, the height h of the heat dissipation column is between 3mm and 8mm. If the height is too low, the flow area of ​​the coolant will be reduced, the flow velocity will increase, and the flow resistance will increase sharply. If the height is too high, the flow velocity will be reduced, which is not conducive to heat exchange.

[0050] Preferably, the diameter d of the heat dissipation column is between 0.5 mm and 2.5 mm. A diameter smaller than 0.5 mm will increase the difficulty of the processing technology, while a diameter larger than 2.5 mm will lead to a decrease in the heat exchange performance of the cylindrical backflow area.

[0051] Preferably, the row spacing a and column spacing b of the heat dissipation column fork row are between 0.9mm-5.5mm, and a and b are within the range of 0.8d-2.2d. Preferably, a=b; if the row spacing a and column spacing b are too narrow, it will cause a sharp increase in flow resistance, and if they are too wide, it will cause a decrease in flow velocity and a decrease in heat exchange performance.

[0052] Preferably, the relative width k / j of the spoiler is between 0.5-5. The smaller the relative width, the lower the disturbance intensity and the limited heat exchange enhancement. The larger the relative width, the more difficult the processing and manufacturing and the significantly increased flow resistance may be.

[0053] Preferably, the spoiler elements are distributed on the side of the heat sink column in an equidistant manner, and the azimuth angle of the distribution area of ​​the spoiler elements on the side of the heat sink column is between -130° and 130°, so that they are respectively arranged on both sides of the front column point of the heat sink column (clockwise is a positive angle, counterclockwise is a negative angle), the front column point is the vertex where the heat sink column contacts the coolant flow direction, 130° is approximately the boundary layer separation point, when the azimuth angle is greater than 130° or less than -130°, the heat exchange enhancement generated by the spoiler element is limited, and it will lead to an increase in flow resistance

[0054] Preferably, the material of the above-mentioned structural parts is pure copper, and the Reynolds number of the coolant is greater than 3000, that is, the flow is in a turbulent state.

[0055] The enhanced heat exchange radiator is prepared by depositing pure copper metal powder using laser selective melting 3D printing technology. The specific preparation method includes the following steps:

[0056] S1. Model design: design a product model; the product model is designed based on a cold plate radiator; the cold plate radiator includes a heat dissipation substrate and a plurality of heat dissipation columns distributed in a staggered manner on the heat dissipation substrate;

[0057] The heat dissipation column extends upward perpendicularly to the heat dissipation substrate, and a plurality of the spoiler elements are equidistantly distributed on a part of the surface of the heat dissipation column at a certain interval; for convective heat transfer in a turbulent state, since the heat transfer between the viscous bottom layer fluid mainly relies on heat conduction, and the thermal conductivity of the coolant is relatively small, the convective heat transfer thermal resistance is mainly concentrated on the viscous bottom layer of the fluid. When the interference flow element is set on the surface of the heat dissipation column, the laminar boundary layer in the viscous bottom layer can be destroyed, and the turbulence of the particles of the viscous bottom layer fluid can be strengthened, forming a heat transfer mode with both conduction and convection, thereby strengthening the convective heat transfer; at the same time, due to the existence of the spoiler element, the heat exchange surface of the heat dissipation column is increased, and the height of the spoiler element is limited, the turbulent effect generated only affects the viscous bottom layer, and the effect on the flow resistance of the radiator is limited. At the same time, the spoiler element may delay the separation of the fluid, that is, increase the shedding azimuth of the fluid, and reduce the backflow vortex area of ​​the cylinder, thereby forming an effect of reducing the flow resistance;

[0058] S2. Model slicing: Slice the designed model, set the layer thickness and printing process parameters (laser power, scanning speed, scanning strategy, etc.), and obtain a product printing process parameter package suitable for pure copper laser selective melting 3D printing process;

[0059] S3, importing the product printing process parameter package into the laser selective melting 3D printer, the 3D printer controls the working state of the printer components according to the process parameter package, and prepares the blank by melting the pure copper metal powder layer by layer;

[0060] S4, heat treating the blank to obtain the product, so as to release the internal stress generated in the product during the printing process, reduce internal defects and improve density;

[0061] S5. The heat-treated product is subjected to surface treatment processes such as sandblasting and polishing to remove surface burrs and micro-protrusions generated during the printing process, improve the surface roughness of the product, and obtain a product form that can be actually used.

[0062] Furthermore, in the above step S3, the particle size of the pure copper metal powder selected is in the range of 15-53 μm, the oxygen content is less than 300 ppm, and the powder morphology is nearly spherical, thereby ensuring that the powder has good fluidity and there will be no problems such as powder agglomeration or failure to spread powder normally during the printing process.

[0063] Specifically, the enhanced heat exchange liquid-cooled radiator can be an open radiator, that is, it only includes a heat dissipation substrate and a heat dissipation component, and forms a complete coolant flow channel (radiator flow channel) with the flow channel base through a sealing ring and a locking screw. It can also be formed into a closed radiator with the heat dissipation bottom plate by welding, and then a radiator flow channel is formed between the heat dissipation substrate and the heat dissipation bottom plate.

[0064] Specifically, in the laser selective melting 3D printing parameter model setting of the heat sink, the laser power is between 600-800w. Too high laser power will lead to unstable molten pool state, prone to internal defects such as spatter and pores, affecting product density; the scanning speed is between 200-600mm / s. Too high scanning speed will lead to low energy density input to the molten pool, unable to fully melt the copper powder. Too low scanning speed may lead to slow product forming speed and excessive melting of the melt channel. The scanning spacing is between 70μm-90μm. Too high scanning spacing may lead to insufficient powder melting. Too low scanning spacing may lead to repeated melting of the melt channel, increase the instability of the molten pool, and slow the forming speed.

[0065] The enhanced heat exchange liquid-cooled radiator provided in this embodiment, by setting a spoiler element on the surface of the heat dissipation column and limiting the structural characteristics and layout position of the spoiler element, can generate a certain intensity of vortex in the near-wall boundary layer without significantly increasing the flow resistance, thereby destroying the laminar viscous bottom layer, promoting turbulence of the laminar boundary layer, reducing the heat transfer thermal resistance of the viscous bottom layer, and thereby enhancing convective heat transfer.

[0066] Finally, it should be noted that the above embodiments are only used to illustrate the technical solution of the present invention rather than to limit it. Although the present invention has been described in detail with reference to the preferred embodiments, those skilled in the art should understand that the technical solution of the present invention can be modified or replaced by equivalents without departing from the purpose and scope of the technical solution, which should be included in the scope of the claims of the present invention.

Claims

1. An enhanced heat exchange liquid cooling radiator, comprising a heat dissipation substrate and a heat dissipation component, wherein the heat dissipation substrate comprises a first surface and a second surface arranged opposite to each other, the first surface is connected to a heat generating device or component, the heat dissipation component is arranged on the second surface of the enhanced heat exchange liquid cooling radiator, and a heat dissipation channel for accommodating the heat dissipation component is provided on one side of the second surface, characterized in that: The heat dissipation component includes heat dissipation columns and spoiler elements. The heat dissipation columns are cylindrical and are distributed on the second surface of the heat dissipation substrate in a cross-row form, and the spoiler elements are distributed on the surface of the heat dissipation columns at intervals.

2. The enhanced heat exchange liquid cooling radiator according to claim 1 is characterized in that: The heat dissipation columns are divided into rows arranged along the flow direction of the radiator liquid cooling medium and columns arranged along the width direction of the radiator, and the row spacing a is 0.9mm≤a≤5.5mm, the column spacing b is 0.9mm≤b≤5.5mm, and 0.8d≤a, b≤2.2d, where d is the diameter of the heat dissipation column.

3. The enhanced heat exchange liquid cooling radiator according to claim 2 is characterized in that: The spoiler is a square column microstructure and is distributed on the surface of the heat dissipation column at a certain interval along the circumferential direction. The protrusion width j and protrusion height k of the spoiler, the width L of the radiator flow channel, the column spacing b of the heat dissipation column, the height h of the heat dissipation column and the diameter d of the heat dissipation column satisfy the following relationship: 0.5≤k / j≤5 The υ is the kinematic viscosity of the coolant in the radiator flow channel, and Q is the volume flow rate of the coolant.

4. The enhanced heat exchange liquid cooling radiator according to claim 3 is characterized in that: The center distance s between two adjacent spoiler elements satisfies the following formula: s / k=9.9(k / j) -0.345 。 5. The enhanced heat exchange liquid cooling radiator according to claim 3 is characterized in that: The height h of the heat dissipation column is 3mm≤h≤8mm, and the diameter d of the heat dissipation column is 0.5mm≤d≤2.5mm.

6. The enhanced heat exchange liquid cooling radiator according to claim 1 is characterized in that: The thickness p of the heat dissipation substrate is between 0.8 mm and 4 mm.

7. The enhanced heat exchange liquid cooling radiator according to claim 1 is characterized in that: The heat dissipation column is a cylinder, and the front stagnation point of the heat dissipation column is set to an azimuth angle of 0°. The azimuth angle of the distribution area of ​​the spoiler element on the heat dissipation column is -130°≤φ≤130°.

8. A method for preparing an enhanced heat exchange radiator, characterized in that: The following steps are involved: S1. A product model for designing an enhanced heat exchange liquid cooling radiator according to any one of claims 1 to 7; S2. Slice the designed product model, set the layer thickness and printing process parameters, and obtain a product printing process parameter package suitable for pure copper laser selective melting 3D printing process; S3. The product printing process parameter package is imported into the laser selective melting 3D printer. The laser selective melting 3D printer controls the working state of the laser selective melting 3D printer according to the product printing process parameter package, and prepares the blank by melting the pure copper metal powder layer by layer; S4. heat treating the blank to obtain a product; S5. Perform a surface treatment process on the heat-treated product to obtain a product that can be actually used.

9. The method for preparing the enhanced heat exchange liquid cooling radiator according to claim 8, characterized in that: The particle size of the pure copper metal powder is in the range of 15-53 μm, the oxygen content is lower than 300 ppm, and the powder morphology is nearly spherical.

10. The method for preparing the enhanced heat exchange liquid cooling radiator according to claim 8, characterized in that: The printing process parameters include laser power, scanning speed and scanning spacing, and the laser power is between 600-800w, the scanning speed is between 200-600mm / s, and the scanning spacing is between 70μm-90μm.

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