Flowing boiling radiator fin structure and design method thereof

Abstract

The invention discloses a flow boiling radiator fin structure and a design method thereof.The flow boiling radiator fin structure comprises a heat dissipation shell and profiling dune sets, the heat dissipation shell is provided with an inlet and an outlet, and the multiple profiling dune sets are fixed in the heat dissipation shell and arranged between the inlet and the outlet in parallel at equal intervals; each profiling sand dune group is formed by arranging a plurality of crescent-imitated sand dune fins at equal intervals, the arrangement direction of the crescent-imitated sand dune fins is perpendicular to the flowing direction from the inlet to the outlet, the protruding end of each crescent-imitated sand dune fin faces the inlet, and the concave end of each crescent-imitated sand dune fin faces the outlet; according to the structure, the flow boiling heat exchange efficiency can be improved, meanwhile, steam bubbles can be effectively guided to be separated from a path, the flow resistance is reduced, the performance adjusting requirements under different heat load and flow conditions are met, the more efficient and more reliable two-phase cooling system structure configuration can be easily achieved, and the heat dissipation requirement of high-heat-flux application is met.

Description

Technical Field

[0001] This invention relates to the field of radiator technology, specifically to a flow boiling radiator fin structure and its design method. Background Technology

[0002] With the development of high heat flux density electronic devices, power modules, and advanced energy systems, the demand for compact and efficient heat dissipation technology is increasing. Flow boiling radiators, which utilize the latent heat of phase change of the working fluid to achieve efficient heat removal, have become an important application in the field of high heat flux density thermal management. During the flow boiling process, the cooling working fluid contacts the heated surface in the flow channel and absorbs heat to vaporize, which can significantly improve the heat transfer capacity per unit volume. However, this process is also accompanied by complex two-phase flow behaviors, such as bubble generation, merging, slippage, and stagnation, which can easily cause problems such as flow blockage, pressure pulsation, and local drying, affecting the stability and efficiency of the radiator. Therefore, how to design a fin structure that is reasonable and takes into account both heat transfer enhancement and flow stability is one of the core issues currently facing the design of flow boiling radiators.

[0003] Currently, most existing flow boiling radiators use regularly arranged straight fins, needle-shaped fins, or serrated fin structures to enhance heat transfer. Although these structures can increase the heat transfer area and enhance turbulent mixing to some extent, their ability to control bubble behavior is weak. Furthermore, while enhancing heat transfer, they often result in significant flow pressure drop and pump power consumption, leading to a decrease in the overall energy efficiency of the radiator system. Some studies have proposed increasing the degree of vapor-liquid mixing by adding turbulence structures (such as transverse fins or vortex generators), but this would significantly increase the fluid pressure drop, which is not conducive to system miniaturization and long-term stable operation. Therefore, there is an urgent need for a new and unconventional fin structure and array method.

[0004] Based on this, researchers discovered that crescent-shaped dunes in nature are typical flow-morphological migration coupling systems in aeolian environments. Their crescent-shaped structural features are formed through the continuous movement and natural optimization of sand grains from original near-cylindrical sand dunes under sustained unidirectional wind action, exhibiting a highly optimized streamlined shape and significant flow drag reduction capabilities as well as airflow guidance and regulation characteristics. The crescent-shaped dunes in nature and their evolution process are as follows: Figure 1 As shown, the rounded leading edge of crescent dunes delays airflow separation and reduces pressure drag. The hook-like structures extending from both sides effectively guide and regulate airflow, reducing tail eddies and flow resistance, and enhancing orderly wake flow. Furthermore, the positional relationships between adjacent crescent dunes are formed through long-term aeolian action and natural evolution. Examples of crescent dune groups and their positional relationships in nature include... Figure 2As shown, this "dust array" or "dust group" is not randomly distributed, but a self-organized and stable arrangement formed through long-term optimization by wind and sand action. It has significant advantages in global wake control, flow stability and group drag reduction. Therefore, the positional relationship of the array spacing between crescent-shaped dunes is also very important. In summary, the crescent-shaped structural features and positional features of crescent-shaped dune groups formed through long-term evolution provide valuable biomimetic design concepts for efficient fluid dynamics design structures. Therefore, the researchers drew on the unique biomimetic optimized shape to design a flow boiling heat dissipation fin structure that imitates crescent-shaped dunes and their clusters. Summary of the Invention

[0005] The purpose of this invention is to overcome the above-mentioned technical deficiencies and propose a flow boiling radiator fin structure and its design method to solve the technical problem of poor heat dissipation effect of traditional rectangular fins in the prior art.

[0006] To achieve the above-mentioned technical objectives, the present invention adopts the following technical solution: This invention provides a flow boiling radiator fin structure and its design method, including a heat dissipation shell and a contoured sand dune assembly. The heat dissipation shell has an inlet and an outlet. Several contoured sand dune assemblies are fixed inside the heat dissipation shell and arranged in parallel at equal intervals between the inlet and the outlet. Each contoured sand dune assembly is composed of multiple crescent-shaped sand dune fins arranged at equal intervals. The arrangement direction of each crescent-shaped sand dune fin is perpendicular to the flow direction from the inlet to the outlet. The protruding end of each crescent-shaped sand dune fin faces the inlet, and the concave end of each crescent-shaped sand dune fin faces the outlet.

[0007] In some embodiments, the crescent-shaped dune fins in any two adjacent dune groups are staggered.

[0008] In some embodiments, the crescent-shaped dune fin has a top profile and a bottom profile, and the ratio of the top profile to the bottom profile is 1:2.

[0009] In some embodiments, the outer wall width W of the heat dissipation shell is 9.5 to 11.5 times the width L4 of the crescent-shaped dune fin.

[0010] In some embodiments, the outer wall width W of the heat dissipation shell is 7.5 to 8.5 times the spacing L5 of the crescent-shaped dune fins in the dune-mimicking group.

[0011] In some embodiments, both the inlet and the outlet are funnel-shaped.

[0012] In some embodiments, designing the crescent-shaped dune-like fins includes the following steps: Step 1: In the crescent dune cluster, measure the positional characteristic dimensions of the minimum cluster layout of adjacent crescent dunes, including dune width L1, dune lateral line spacing L2, and dune front-to-back spacing L3; Step 2: Construct a bottom reference plane using the inner bottom plane of the heat sink; Step 3: Measure the width W of the outer wall of the heat sink. Based on W = (13~14)·H1 and W = (13.5~15)·H2, calculate H1 and H2. Step 4: Determine the bottom reference origin based on H1 and H2, and use it as the curve equation y1. ' y2 ' y3 ' and y4 ' The bottom outline of the crescent-shaped sand dune fins was drawn based on the design origin. Step 5: Measure the height H4 of the inner wall of the heat sink, and calculate H3 according to H4 = (1.2~1.3)·H3; Step 6: Construct a top reference plane that is parallel to the bottom reference plane based on H3; Step 7: Based on W = (18.5~20.5)·L The distance L between the bottom reference origin and the top reference origin along the x-direction is obtained. ; Step 8: According to L Determine the top reference origin and use it as the curve equation y. 1-2 ' y 2-2 ' y 3-2 ' and y 4-2 ' The top outline of the crescent-shaped sand dune fins was drawn based on the design origin. Step 9: Connect the top and bottom outlines to form guide lines, and then form crescent-shaped dune fins by lofting.

[0013] In some embodiments, the y1 ' y2 ' y3 ' and y4 ' The mathematical model is as follows: .

[0014] In some embodiments, the y 1-2 ' y 2-2 ' y 3-2 ' and y 4-2 ' The mathematical model is as follows: .

[0015] In some embodiments, the mathematical models for y1, y2, y3, and y4 are as follows: , where χ is the position where feature points are extracted from the bottom contour line.

[0016] Compared with the prior art, the fluidized bed radiator fin structure and its design method provided by the present invention effectively increase the heat exchange area, enhance the orderly flow, guidance and heat exchange efficiency of the coolant, and reduce flow resistance and pump power consumption, thereby achieving efficient, stable and energy-saving heat dissipation, meeting the thermal management requirements of modern high power density devices. Compared with traditional rectangular fins, the crescent-shaped dune fin can reduce flow energy loss by 30% and increase the heat transfer rate by 25%. Attached Figure Description

[0017] Figure 1 To understand the crescent-shaped dune clusters that evolved in the desert under the influence of natural winds and their evolutionary process; Figure 2 for Figure 1 Shape feature extraction from images of a single crescent-shaped dune and two adjacent crescent-shaped dune clusters; Figure 3 for Figure 2 The positional characteristic dimensions of the minimum cluster layout of adjacent crescent-shaped dunes in the middle and front; Figure 4 for Figure 3 Extraction of the feature contour lines of crescent-shaped dunes in central China; Figure 5 for Figure 4 Extraction of feature points of the sand dune contour and corresponding curve fitting and reconstruction; Figure 6 The construction process of crescent-shaped dune fins in a design method for a flow boiling radiator fin structure provided in an embodiment of the present invention; Figure 7 A three-dimensional diagram of a flow boiling radiator fin structure provided in an embodiment of the present invention; Figure 8 for Figure 7 Top view; Figure 9 for Figure 7 A sectional view.

[0018] Explanation of reference numerals in the attached drawings: 1. Heat sink housing; 11. Inlet; 12. Outlet; 13. Working area; 2. Contour sand dune assembly; 21. Contour crescent-shaped sand dune fins; 211. Top outline; 212. Bottom outline; 213. Guide line; 3. Bottom reference plane; 31. Bottom reference origin; 4. Top reference plane; 41. Top reference origin. Detailed Implementation

[0019] To make the objectives, technical solutions, and advantages of this invention clearer, the invention will be further described in detail below with reference to the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are merely for explaining the invention and are not intended to limit the invention.

[0020] To address the technical problem of poor heat dissipation performance of traditional rectangular fins, this invention provides a flow boiling radiator fin structure and its design method, which can simultaneously improve the heat exchange efficiency and reduce flow resistance loss of the flow boiling radiator.

[0021] It should be noted that the fluidized bed radiator fin structure and its design method described in this invention are used in, but not limited to, radiators. For ease of explanation, this invention will only use the application of a fluidized bed radiator fin structure and its design method to a radiator as an example. The principle of applying a fluidized bed radiator fin structure and its design method to other types of equipment is essentially the same as that applied to radiators, and will not be elaborated here.

[0022] Please see Figures 1 to 9 ,in Figure 7 This is a schematic diagram of the structure of a flow boiling radiator fin according to an embodiment of the present invention. The flow boiling radiator fin structure includes a heat dissipation shell 1 and a contoured sand dune group 2. The heat dissipation shell 1 has an inlet 11 and an outlet 12. Several contoured sand dune groups 2 are fixed inside the heat dissipation shell 1 and are arranged in parallel at equal intervals between the inlet 11 and the outlet 12. Each contoured sand dune group 2 is composed of multiple crescent-shaped sand dune fins 21 arranged at equal intervals. The arrangement direction of each crescent-shaped sand dune fin 21 is perpendicular to the flow direction from the inlet 11 to the outlet 12. The protruding end of each crescent-shaped sand dune fin 21 faces the inlet 11, and the concave end of each crescent-shaped sand dune fin 21 faces the outlet 12.

[0023] On the one hand, it effectively increases the heat exchange area; on the other hand, it effectively enhances the orderly flow, guidance and heat exchange efficiency of the coolant; and on the third hand, it effectively reduces flow resistance and pump power consumption, achieving efficient, stable and energy-saving heat dissipation, meeting the thermal management needs of modern high power density devices. Compared with traditional rectangular fins, the crescent-shaped dune fin 21 can reduce flow energy loss by 30% and increase the heat transfer rate by 25%.

[0024] In this embodiment, as Figure 1As shown, the researchers referenced the crescent-shaped dune structure formed naturally by the continuous movement and long-term optimization of sand grains in primitive cylindrical sand dunes under sustained unidirectional wind. The overall shape of the crescent-shaped dune resembles a crescent or half-moon, with a smooth, arc-shaped leading edge near the windward side. This effectively diverts incoming airflow and delays frontal airflow separation, while also reducing pressure drag during flow. The two flanks on either side have a backward-extending hook-like structure with naturally curved, swept-back ends. This effectively guides and regulates airflow to reduce flow resistance and enhances orderly high-speed circulation, while also reducing the low-speed wake region at the dune's rear. Figure 1 Images of single crescent-shaped dune structures and the smallest dune groups formed by two crescent-shaped dunes in nature, as shown in the image. Figure 2 As shown, it can be found that individual crescent-shaped dunes have similar shapes, and the positional relationship between two adjacent crescent-shaped dunes is also basically the same. This discovery provides a valuable biomimetic design concept for efficient fluid dynamics design structures, making it easier for researchers to learn from unique biomimetic optimized shapes, extract the characteristic contour lines of crescent-shaped dunes, and then design corresponding curve fitting and reconstruction by extracting the feature points of the dune contour lines.

[0025] In one embodiment, please refer to Figure 7 and Figure 8 The crescent-shaped dune fins 21 in any two adjacent dune groups 2 are staggered, that is, they are staggered in front and behind.

[0026] The coolant flows through the inlet 11 of the heat sink 1 and through the working area 13 of the heat sink 1. Here, under the flow control of the crescent-shaped dune fin cluster 21, it undergoes efficient boiling heat exchange and then flows out through the outlet 12. During this heat exchange process, the crescent-shaped dune fin cluster 21 achieves a large heat exchange surface area, which can guide the upstream airflow to form a more uniform and stable flow path in the staggered array, reducing the flow pressure drop loss. The staggered distribution of the front and rear crescent-shaped dune fins 21 can reduce the overlap of low-speed stagnant vortices, suppress flow dead zones, promote orderly high-speed turbulent flow, thereby enhancing coolant replenishment and promoting bubble detachment, and improving heat transfer efficiency.

[0027] In one embodiment, please refer to Figures 6 to 8 The crescent-shaped dune fin 21 has a top outline 211 and a bottom outline 212, and the ratio of the top outline 211 to the bottom outline 212 is 1:2, that is, the top outline 211 is 0.5 times the scale of the bottom outline 212, and the top outline 211 is obtained by reducing the bottom outline 212 by 0.5 times.

[0028] In one embodiment, please refer to Figure 8The outer wall width W of the heat sink 1 is 9.5 to 11.5 times the width L4 of the crescent-shaped sand dune fin 21. The length of W can be determined by instrument measurement, and the length of L4 can be calculated by W=(9.5 to 11.5)·L4.

[0029] Furthermore, after obtaining the L4 of the crescent-shaped dune fin 21, it is possible to obtain... Figure 3 L1 and Figure 7 The multiple relationship of L4 is L1 / L4, that is, the fitted curve equations (y1, y2, y3, and y4) of the bottom contour line 212 and the fitted curve equations (y4, y5, y6, and y7) of the top contour line 211. 1-2 y 2-2 y 3-2 and y 4-2 All of them need to be scaled proportionally.

[0030] In one embodiment, please refer to Figure 8 The outer wall width W of the heat dissipation shell 1 is 7.5 to 8.5 times the spacing L5 of the crescent-shaped sand dune fins 21 in the sand dune group 2. The length of L5 can be calculated by W = (7.5 to 8.5)·L5.

[0031] In one embodiment, both the inlet 11 and the outlet 12 are funnel-shaped to facilitate the dispersion and collection of coolant.

[0032] In one embodiment, please refer to Figures 3 to 6 The design of the crescent-shaped dune fin 21 includes the following steps: Step 1: In the crescent dune cluster, measure the positional characteristic dimensions of the minimum cluster layout of adjacent crescent dunes, including dune width L1, dune lateral line spacing L2, and dune front-to-back spacing L3; Step 2: Construct the bottom reference surface 3 using the inner bottom plane of the heat sink 1; Step 3: Measure the width W of the outer wall of the heat sink 1. Based on W = (13~14)·H1 and W = (13.5~15)·H2, obtain H1 and H2. Step 4: Determine the bottom reference origin 31 based on H1 and H2, and use it as the curve equation y1. ' y2 ' y3 ' and y4 ' The bottom outline 212 of the crescent-shaped sand dune fin 21 is drawn from the design origin; Step 5: Measure the height H4 of the inner wall of the heat sink 1, and calculate H3 according to H4 = (1.2~1.3)·H3; Step 6: Construct a top reference plane 4 that is parallel to the bottom reference plane 3 based on H3; Step 7: Based on W = (18.5~20.5)·L The distance L along the x-direction between the bottom reference origin 31 and the top reference origin 41 is obtained. ; Step 8: According to L The top reference point 41 is determined and used as the equation of the curve y. 1-2 ' y 2-2 ' y 3-2 ' and y 4-2 ' The top outline 211 of the crescent-shaped sand dune fin 21 is drawn from the design origin; Step 9: Connect the top outline 211 and the bottom outline 212 to form the guide line 213, and form the crescent-shaped dune fin 21 by lofting.

[0033] It should be noted that both the bottom reference plane 3 and the top reference plane 4 are horizontal planes, and the bottom reference origin 31 and the top reference origin 41 are located on the same vertical plane.

[0034] It is important to note that, such as Figure 3 In the diagram, L1, L2, and L3 are known values ​​measured by surveying instruments. The relative positional relationship of the smallest dune group formed by two adjacent crescent-shaped dunes is as follows: Figure 3 As shown, the dunes exhibit a staggered distribution pattern, with the rear dunes situated in the low-velocity wake region of the front dunes. This positional relationship is the result of flow optimization under the long-term evolution of wind and sand in nature. It can reduce flow drag and induce flow, reduce wake region overlap to avoid interference from large-area low-velocity stagnant vortices, and at the same time promote beneficial turbulent flow.

[0035] In one embodiment, please refer to Figures 4 to 6 y1 ' y2 ' y3 ' and y4 ' The mathematical model is as follows: .

[0036] In one embodiment, please refer to Figures 4 to 6 y 1-2 ' y 2-2 ' y 3-2 ' and y 4-2 ' The mathematical model is as follows: .

[0037] In one embodiment, please refer to Figure 5The mathematical models for y1, y2, y3, and y4 are as follows: Where χ represents the location of feature point extraction for the bottom contour line 212, and to facilitate equation fitting for the bottom contour line 212, according to... Figure 4 The extracted curve curvature features divide the curves into curve 1, curve 2, curve 3, and curve 4. Feature points are then extracted from each of the four curves, and polynomial equations are fitted to obtain the curves shown below. Figure 4 The fitted curves of the bottom contour line 212 and the corresponding fitted curve equations y1 (fitted curve 1), y2 (fitted curve 2), y3 (fitted curve 3) and y4 (fitted curve 4).

[0038] To better understand this invention, the following is combined with... Figures 1 to 9 The technical solution of the present invention will be described in detail below: The global distribution of the crescent-shaped sand dune fins 21 inside the heat sink 1 is based on ( Figure 3 and Figure 8 The relative positions of the smallest dune groups are used to determine the alignment, with adjacent crescent-shaped dune fins 21 showing misalignment. Figure 8 The lateral spacing between adjacent crescent-shaped dune fins 21 in the middle and front is L6, and... Figure 3 The L3 corresponds to the contour fitting curve equation and is scaled according to the scaling factor L1 / L4, i.e., L6 = L3 / (L1 / L4); the distance between the lower side line of the front fin and the upper side line of the rear fin of the adjacent crescent-shaped dune fins 21 is L7, which corresponds to the L3 in the equation. Figure 3 The L2 in the model is obtained by scaling it proportionally, i.e., L7 = L2 / ( L1 / L4). Therefore, the cluster layout design of the crescent-shaped dune fins 21 is established according to the adjacent spacing L5, the lateral spacing L6 of the adjacent crescent-shaped dune fins 21, and the adjacent side line spacing L7. The coolant flows through the inlet 11 of the heat sink 1 and through the working area 13 of the heat sink 1. Here, under the flow control of the crescent-shaped sand dune fin cluster 21, it undergoes efficient boiling heat exchange and then flows out through the outlet 12. This process can improve the flow boiling heat exchange efficiency, effectively guide the bubbles to leave the path, reduce flow resistance, and adapt to the performance adjustment requirements under different heat load and flow conditions. This will help to achieve a more efficient and reliable two-phase cooling system structure to meet the heat dissipation requirements of high heat flux density applications.

[0039] The specific embodiments of the present invention described above do not constitute a limitation on the scope of protection of the present invention. Any other corresponding changes and modifications made in accordance with the technical concept of the present invention should be included within the scope of protection of the claims of the present invention.

Claims

1. A flow boiling radiator fin structure, characterized in that, include: A heat dissipation housing having an inlet and an outlet; as well as The sand dune assembly consists of several sand dune fins fixed inside the heat dissipation shell and arranged in parallel at equal intervals between the inlet and the outlet. Each sand dune assembly is composed of multiple crescent-shaped sand dune fins arranged at equal intervals, and the arrangement direction of each crescent-shaped sand dune fin is perpendicular to the flow direction from the inlet to the outlet. The protruding end of each crescent-shaped sand dune fin faces the inlet, and the concave end of each crescent-shaped sand dune fin faces the outlet.

2. The flow boiling radiator fin structure according to claim 1, characterized in that, The crescent-shaped dune fins in any two adjacent dune groups are staggered.

3. The flow boiling radiator fin structure according to claim 1, characterized in that, The crescent-shaped dune fin has a top outline and a bottom outline, and the ratio of the top outline to the bottom outline is 1:

2.

4. The flow boiling radiator fin structure according to claim 1, characterized in that, The outer wall width W of the heat dissipation shell is 9.5 to 11.5 times the width L4 of the crescent-shaped dune fin.

5. The flow boiling radiator fin structure according to claim 1, characterized in that, The outer wall width W of the heat dissipation shell is 7.5 to 8.5 times the spacing L5 of the crescent-shaped dune fins in the dune-mimicking group.

6. The flow boiling radiator fin structure according to claim 1, characterized in that, Both the import and the export are funnel-shaped.

7. A design method for a flow boiling radiator fin structure, characterized in that, Its application to the flow boiling radiator fin structure according to any one of claims 1-6, and the design of the crescent-shaped dune fin includes the following steps: Step 1: In the crescent dune cluster, measure the positional characteristic dimensions of the minimum cluster layout of adjacent crescent dunes, including dune width L1, dune lateral line spacing L2, and dune front-to-back spacing L3; Step 2: Construct a bottom reference plane using the inner bottom plane of the heat sink; Step 3: Measure the width W of the outer wall of the heat sink. Based on W = (13~14)·H1 and W = (13.5~15)·H2, calculate H1 and H2. Step 4: Determine the bottom reference origin based on H1 and H2, and use it as the curve equation y1. ' y2 ' y3 ' and y4 ' The bottom outline of the crescent-shaped sand dune fins was drawn based on the design origin. Step 5: Measure the height H4 of the inner wall of the heat sink, and calculate H3 according to H4 = (1.2~1.3)·H3; Step 6: Construct a top reference plane that is parallel to the bottom reference plane based on H3; Step 7: Based on W = (18.5~20.5)·L The distance L between the bottom reference origin and the top reference origin along the x-direction is obtained. ; Step 8: According to L Determine the top reference origin and use it as the equation of the curve y. 1-2 ' y 2-2 ' y 3-2 ' and y 4-2 ' The top outline of the crescent-shaped sand dune fins was drawn based on the design origin. Step 9: Connect the top and bottom outlines to form guide lines, and then form crescent-shaped dune fins by lofting.

8. The design method for a flow boiling radiator fin structure according to claim 7, characterized in that, The y1 ' y2 ' y3 ' and y4 ' The mathematical model is as follows: .

9. The design method for a flow boiling radiator fin structure according to claim 8, characterized in that, The y 1-2 ' y 2-2 ' y 3-2 ' and y 4-2 ' The mathematical model is as follows: .

10. The design method of a flow boiling radiator fin structure according to claim 9, characterized in that, The mathematical models for y1, y2, y3, and y4 are as follows: , where χ is the position where feature points are extracted from the bottom contour line.

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