Multi-duct fairing, radiator, and control method

Abstract

This invention discloses a multi-channel airflow guide shroud, a heat sink, and a control method, relating to the field of heat dissipation technology. The airflow guide structure of the shroud divides the internal space into independent first airflow channels, second airflow channels, and a central airflow channel. The first and second airflow channels are used to guide airflow to the first and second airflow receiving surfaces of the heat-generating device, respectively. Additionally, both the first and second airflow channels have gradually narrowing and expanding regions along the airflow direction. Under the Venturi effect, the fluid static pressure decreases while the flow velocity increases simultaneously, thus enhancing convective heat transfer. The central airflow channel guides airflow towards the windward surface of the heat-generating device. Because the airflow allocated to this area is relatively small, it avoids significant dynamic pressure loss caused by turbulent dissipation due to stagnation point impact. Based on global flow distribution, the final goal is to fully utilize the effective total pressure of the fan and enhance heat transfer.

Description

Technical Field

[0001] This invention relates to the field of heat dissipation technology, specifically to a multi-channel airflow guide shroud, a heat sink, and a control method. Background Technology

[0002] In the high-voltage box of an energy storage system, current-carrying devices such as fuses and shunts generate significant heat due to the Joule heating effect when subjected to large currents. If heat dissipation is not timely, it will lead to device performance degradation, malfunction, and in severe cases, even thermal runaway. This is one of the key bottlenecks affecting the long-term reliable operation of the high-voltage box.

[0003] To address the aforementioned overheating issue, existing technologies typically involve installing axial or centrifugal fans inside the high-pressure chamber, directing forced airflow directly at the heat-generating components for cooling. While this approach can reduce the temperature of the heat-generating components to some extent, it reveals the following problems in practical applications: First, the high airflow requirement leads to high energy consumption and noise. Heat-generating components such as fuses and shunts are typically cuboid in shape, with a large surface area facing the fan. This surface has non-smooth structures such as terminals and grooves, resulting in significant form and frictional resistance as airflow passes over it. To ensure sufficient airflow over this high-resistance surface, the fan must operate at high speed and high flow rate, increasing system energy consumption. Simultaneously, the fan's noise and vibration also increase, negatively impacting on-site applications.

[0004] Secondly, the airflow distribution is unreasonable, resulting in significant ineffective air resistance losses. The air resistance characteristics of different surfaces of heat-generating devices vary significantly. Typically, the air resistance of the front surface is higher, while the air resistance of the adjacent or opposite sides and back surface is relatively lower. Existing single-fan direct-blowing solutions struggle to differentiate airflow distribution for different surfaces. This forces most of the airflow to collide with and bypass the high-resistance front surface, resulting in substantial dynamic pressure losses. Meanwhile, the sides and back surfaces, with lower air resistance and potentially higher heat dissipation potential, fail to receive sufficient airflow and thus fail to fully utilize their cooling capabilities, leading to unreasonable airflow distribution and significant ineffective air resistance losses.

[0005] Third, turbulence and eddies exacerbate airflow waste. When a fan blows air directly, the high-speed airflow directly impacts the surface of the heat-generating device, easily forming large-scale turbulence and backflow eddies around the device. This turbulent airflow does not effectively participate in heat dissipation; instead, it increases the local resistance within the flow channel, further consuming the effective airflow and reducing the actual heat dissipation effect.

[0006] In summary, existing fan-based direct-blowing cooling solutions suffer from drawbacks such as high airflow requirements, high energy consumption and noise, unreasonable airflow distribution, severe ineffective air resistance losses, and waste of effective airflow due to airflow turbulence. These shortcomings make it difficult to meet the actual needs of energy storage systems for high power density, low energy consumption, and long-life cooling. Summary of the Invention

[0007] This invention provides a multi-channel airflow guide cover, a heat sink, and a control method, which solves the technical problems of existing heat dissipation devices, such as high airflow demand, high energy consumption and noise, unreasonable airflow distribution, serious ineffective wind resistance loss, and airflow waste exacerbated by turbulence and eddies.

[0008] To achieve the above objectives, the present invention provides a multi-channel airflow guide shroud for heat dissipation of heat-generating devices, comprising: A flow guide shroud, wherein the interior of the flow guide shroud is provided with a mounting position for mounting the heating device; The air guide shroud has an internal air guiding structure that divides the internal space of the air guide shroud into three independent air ducts: a first air duct, a second air duct, and a central air duct. Along a first direction, the air inlet of the central air duct is located between the air inlets of the first air duct and the second air duct. Fans are installed at the air inlets of the first air duct, the second air duct, and the central air duct. The first air duct is used to guide airflow to the first air-receiving surface of the heating device, and the second air duct is used to guide airflow to the second air-receiving surface of the heating device; the first air-receiving surface and the second air-receiving surface are opposite to each other and are both adjacent to the windward surface of the heating device; the airflow entering the first air duct and the second air duct bypasses the first air-receiving surface and the second air-receiving surface of the heating device respectively, and then exits from the rear of the air guide cover; Both the first and second air ducts are provided with a gradually narrowing region and a gradually expanding region along the airflow direction. The cross-section of the flow channel in the gradually narrowing region gradually decreases along the airflow direction, and the cross-section of the flow channel in the gradually expanding region gradually increases along the airflow direction. The central air duct is used to guide airflow toward the windward side of the heating device.

[0009] Optionally, along the second direction, the length of the central air duct is greater than the width of the heating device; The central air duct guides the airflow toward the windward side of the heating device. The airflow then passes around both ends of the heating device along the second direction and is discharged from the air outlets on both sides of the air guide cover.

[0010] Optionally, the flow guiding structure includes a flow guiding plate and reinforcing ribs located on both sides of the flow guiding shroud along the second direction; The leeward edge of the deflector plate overlaps the windward side of the heating element, and the reinforcing rib is used to contact and limit the heating element, so as to cooperate with the heating element to divide the internal space of the deflector shroud into the central air duct, the first air duct and the second air duct.

[0011] Optionally, the guide vane is an inclined surface, and two guide vanes together form a funnel-shaped, gradually expanding area of ​​the central air duct; The air inlet area of ​​the central air duct is smaller than the air inlet area of ​​the first air duct and smaller than the air inlet area of ​​the second air duct, so that the air volume entering the first air duct and the second air duct is greater than the air volume entering the central air duct.

[0012] Optionally, the flow guide includes a first flow guide shell and a second flow guide shell that are fixed to each other and are axially symmetrical; The first flow guide shell and the second flow guide shell are fixed together by snap-fit ​​connection.

[0013] Optionally, the first air duct and the second air duct sequentially include, along the airflow direction: First narrowing section, second narrowing section, third turning section, fourth widening section, fifth turning section, sixth straight section; The first tapering section and the second tapering section are located to the side of the heating device along the first direction; the fourth expanding section, the fifth turning section, and the sixth straight section are located to the rear of the heating device along the third direction.

[0014] Optionally, the outer contour of the fairing has a tapering region along a third direction.

[0015] The present invention also provides a heat sink, comprising the multi-channel airflow guide shroud as described in any one of the preceding claims, and: The fan is located at the air inlet of the first air duct, the second air duct, and the middle air duct, and is used to deliver airflow into the air guide shroud.

[0016] The present invention also provides a control method applied to the multi-duct air guide shroud described in any of the above claims, comprising: Determine the cross-sectional area of ​​the air inlets of the first air duct, the second air duct, and the middle air duct; along the first direction, the air inlet of the middle air duct is located between the air inlets of the first air duct and the air inlets of the second air duct; Set the shrinkage ratio of the shrinkage regions of the first and second air ducts; According to the tapering ratio, the tapering regions of the first air duct and the second air duct are designed; the first air duct is used to guide the airflow to the first air-receiving surface of the heating device, and the second air duct is used to guide the airflow to the second air-receiving surface of the heating device; the middle air duct is used to guide the airflow to blow towards the windward surface of the heating device.

[0017] Optionally, the size ratio of the tapering regions of both the first and second air ducts to the expanding regions following the tapering regions is determined: Establish a fluid dynamics model for the first or second air duct and the middle air duct; based on the fluid dynamics model, input initial parameters, including: initial environmental parameters, fluid characteristic parameters, structural parameters, and the selected fan PQ curve; based on the solved middle air duct flow rate Qside and the first or second air duct flow rate Qmain, continue to solve for the fan static pressure Pfan,provide corresponding to the current total flow rate. A heat transfer model is established, a set of heat-fluid coupling equations is constructed, and the steady-state temperature of the heating device when it reaches thermal equilibrium is calculated. Based on the fluid dynamics model and the heat transfer model, calculate the steady-state temperature of the heating device when it reaches thermal equilibrium. Keeping the inlet size of the contracting region constant, the outlet size of the contracting region is used as the independent variable for parameter scanning to generate a contraction ratio-steady-state temperature correlation curve. The size ratio corresponding to the global minimum point of the contraction ratio-steady-state temperature correlation curve is determined as the optimal contraction ratio. Keeping the inlet size of the expanding region constant, the outlet size of the expanding region is used as the independent variable for parameter scanning to generate a expanding ratio-steady-state temperature correlation curve. The size ratio corresponding to the global minimum point of the expanding ratio-steady-state temperature correlation curve is determined as the optimal expanding ratio. The dimensions of the tapered region and the expanded region are set according to the optimal tapering ratio and the optimal expanding ratio.

[0018] Optionally, the fluid dynamics model includes formulas for calculating the local pressure drop of each segment as the airflow passes through the first converging segment, the second converging segment, the third turning segment, the fourth expanding segment, the fifth turning segment, and the sixth straight segment. The sum of the local pressure drops of each segment is the total pressure drop of the first air duct or the second air duct.

[0019] Optionally, the heat transfer model includes the convective heat transfer coefficients of the windward and leeward sides of the heating device calculated based on the Reynolds number and Prandtl number, and the total heat transfer of the first and second air ducts calculated based on the convective heat transfer coefficients, the windward and leeward areas of the heating device, and the temperature difference between the steady-state temperature of the heating device at thermal equilibrium and the ambient temperature.

[0020] The multi-channel airflow guide shroud provided by this invention, by setting up independent first, second, and central airflow channels, and utilizing a flow-guiding structure to direct airflow to the windward, first, and second windward surfaces of the heat-generating device, achieves heat dissipation on all four surfaces, improving heat dissipation efficiency and the uniformity of surface temperature distribution. The tapered and expanding regions in the first and second airflow channels utilize the Venturi effect to accelerate airflow in the tapered region. This allows for accelerated airflow through a contracted cross-section in the windward surface area where the heat-generating device has low wind resistance, achieving efficient heat exchange with a smaller airflow volume and enhancing the heat dissipation effect. In the windward surface area where wind resistance is high, only a small amount of airflow is allocated, avoiding significant dynamic pressure loss due to turbulent dissipation caused by stagnation point impacts. Therefore, excellent heat dissipation performance can still be achieved even with a low total system airflow. This reduces energy consumption and noise, makes airflow distribution more rational, and avoids the generation of turbulence and eddies to prevent airflow waste. Attached Figure Description

[0021] To more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0022] Figure 1A This is a front view of the multi-channel airflow guide cover of the present invention; Figure 1B This is a side view of the multi-channel air guide shroud of the present invention; Figure 1C This is a rear view of the multi-channel air guide shroud of the present invention; Figure 1D for Figure 1B Cross-sectional view along the AA direction; Figure 1E A diagram showing the relative relationships of airflow in the direction of direct view; Figure 2 Axonometric views of the first and second flow guide shells; Figure 3A This is an isometric view of the second guide shell; Figure 3B An isometric view of the second flow guide shell and the heating element in conjunction; Figure 4A This is a schematic diagram of the airflow in the first and second air ducts in the longitudinal cross-section of the deflector. Figure 4B This is a schematic diagram of the airflow in the central duct of the longitudinal cross-section of the fairing; Figure 4C This is a schematic diagram of the airflow in the central duct of the fairing in an isometric drawing; Figure 5A This is a first-view isometric view of the heat sink of the present invention; Figure 5B This is a second-view isometric view of the heat sink of the present invention; Figure 5C This is a side view of the heat sink of the present invention; Figure 5D This is an exploded view of the heat sink of the present invention; Figure 6A These are the four airflow sections inside the fairing; Figure 6B The streamline distribution inside the fairing; Figure 7A For steady-state temperature T and tapering ratio Change relationship diagram; Figure 7B For steady-state temperature T and diffusion ratio Change relationship diagram; Figure 8 To obtain the fan static pressure Pfan corresponding to the current total flow rate based on the fluid dynamics model, provide the logic flowchart.

[0023] The image includes: fairing 10; First air duct 10-1; Second air duct 10-2; Central air duct 10-3; 101; 102; 103; 104; 105; First flow guide shell 110; elastic buckle 111; second flow guide shell 120; elastic groove 121; Fan 20; Central swirl area 210; Blade section 220; Heating element 30; Terminal block 301; Bracket 40; First contraction section S1; second contraction section S2; third turning section S3; fourth expansion section S4; fifth turning section S5; sixth straight section S6. Detailed Implementation

[0024] To make the objectives, technical solutions, and advantages of the present invention clearer, the specific embodiments of the present invention will be further described in detail below with reference to the accompanying drawings. It should be understood that the specific embodiments described herein are only for explaining the present invention and are not intended to limit the scope of protection of the present invention.

[0025] For ease of description, this specification defines a first direction (Y), a second direction (Z), and a third direction (X) that are perpendicular to each other: the first direction is the distribution direction of the first air duct 10-1 and the second air duct 10-2 relative to the central air duct 10-3, as shown in the figure. Figure 1AThe first direction is shown as the Y-axis in the vertical direction; the second direction is the length extension direction of the heating device 30, which is perpendicular to the first direction. The second direction is as follows: Figure 1A The left-right direction is shown on the Z-axis; the third direction is the overall flow direction of airflow from the side where the air inlet of the shroud 10 is located to the side where the rear of the shroud 10 is located, that is, the front-back direction. The third direction is perpendicular to both the first and second directions. Specific orientations can be determined by combining... Figures 5A to 5D understand.

[0026] like Figure 1A , Figure 1B , Figure 1C As shown, this embodiment provides a multi-channel airflow guide shroud for heat dissipation of the heat-generating device 30. This design utilizes the Venturi effect, a phenomenon in fluid mechanics, which states that when fluid passes through a gradually narrowing or expanding cross-section pipe, the gradually decreasing cross-section causes the flow velocity to increase and the static pressure to decrease, while the gradually increasing cross-section causes the flow velocity to decrease and the static pressure to increase.

[0027] The side of the heating device 30 facing the incoming flow is the windward side, which has a higher wind resistance. The first and second windward sides adjacent to the windward side have relatively lower wind resistance. Specifically, the heating device 30 can be a cuboid current-carrying device such as a fuse, circuit breaker, or shunt in the high-voltage box of the energy storage system, which generates significant heat due to the Joule heating effect when carrying a large current. The heating device 30 can also be other heating components such as IGBT (Insulated Gate Bipolar Transistor) modules, relays, and transformers, which are cuboid or approximately cuboid and have different wind resistance characteristics on different surfaces.

[0028] The air deflector 10 has a mounting position inside, and the heating element 30 is fixedly installed in this mounting position. The heating element 30 and the air deflector 10 are installed together as a single unit. Figure 3B As shown, the length of the heating element 30 is along the second direction, and each end of the heating element 30 along the second direction is provided with a wiring terminal 301, which extends beyond the flow guide shroud 10. Figure 1D As shown, except for the wiring terminal 301, the heating device 30 is located entirely inside the cavity of the flow guide shroud 10.

[0029] The airflow guide shroud 10 also has an internal airflow guide structure. This structure cooperates with the outer surface of the installed heating element 30 to divide the internal space of the airflow guide shroud 10 into three independent and non-interconnected airflow channels: a first airflow channel 10-1, a second airflow channel 10-2, and a central airflow channel 10-3. Through the cooperation of the airflow guide structure and the heating element 30, the internal space of the airflow guide shroud 10 is divided into at least three relatively independent spaces. The number of spaces can be more than three, and each space independently circulates airflow for heat dissipation.

[0030] like Figure 1E As shown, along the first direction (Y), the air inlet of the central air duct 10-3 is located between the air inlets of the first air duct 10-1 and the second air duct 10-2, meaning the central air duct 10-3 is centrally located, with the first air duct 10-1 and the second air duct 10-2 situated on either side of the central air duct 10-3 along the first direction. Fans 20 are installed at the air inlets of the first air duct 10-1, the second air duct 10-2, and the central air duct 10-3. The airflow generated by the fans 20 during operation enters the corresponding air ducts through these three inlets. It should be noted that the first air duct 10-1, the second air duct 10-2, and the central air duct 10-3 can share a single fan 20, or two or more fans can be arranged.

[0031] The present invention generates airflow by setting a fan 20 at the air inlet of the air guide shroud 10. The airflow is driven by the first air duct 10-1 and the second air duct 10-2 to form a Venturi effect, thereby increasing the flow speed of the airflow and helping to improve the heat exchange efficiency.

[0032] The heating element 30 has a frontal surface, a first air-receiving surface, and a second air-receiving surface. The frontal surface is the surface of the heating element 30 facing the incoming airflow from the fan 20. The first air-receiving surface and the second air-receiving surface are arranged opposite each other and are both adjacent to the frontal surface. The central air duct 10-3 is used to guide the airflow towards the frontal surface of the heating element 30. The first air duct 10-1 is used to guide the airflow to the first air-receiving surface of the heating element 30, and the second air duct 10-2 is used to guide the airflow to the second air-receiving surface of the heating element 30. The first air duct 10-1 and the second air duct 10-2 respectively guide the airflow to impact the first air-receiving surface and the second air-receiving surface at a certain angle. The airflow entering the first air duct 10-1 and the second air duct 10-2 bypasses the first air-receiving surface and the second air-receiving surface of the heating element 30 and is discharged from the rear of the guide shroud 10, that is, discharged to the external environment in a third direction.

[0033] Both the first air duct 10-1 and the second air duct 10-2 have a gradually narrowing region and a gradually expanding region arranged sequentially along the airflow direction: the cross-section of the flow channel in the gradually narrowing region gradually decreases along the airflow direction, and the cross-section of the flow channel in the gradually expanding region gradually increases along the airflow direction. It should be noted that the gradually narrowing region and the gradually expanding region can be distributed in a straight line along a third direction, or they can form a bend in the distribution.

[0034] Based on the principle of continuity of incompressible fluids, as the airflow passes through the contracting region, the cross-section gradually shrinks, and the flow velocity continuously increases, reaching a high velocity at the end of the contracting region. This significantly improves the average flow rate between the first and second air-receiving surfaces of the heating device 30, thus enhancing the convective heat transfer coefficient and achieving efficient heat exchange. Subsequently, as the airflow enters the expanding region, the cross-section gradually increases, avoiding excessive local resistance losses due to the continuous narrowing of the flow channel. This allows the airflow to maintain a high velocity while carrying away heat, keeping wind resistance losses within a reasonable range. Therefore, the first air duct 10-1 and the second air duct 10-2 utilize the Venturi effect to achieve efficient convective heat transfer at the relatively low wind resistance surfaces of the heating device 30.

[0035] Using the multi-channel air guide shroud provided by the present invention, after the fan 20 is started, the total air volume generated is divided into three paths by the air guide structure at the air inlet of the air guide shroud 10: one path blows through the middle air duct 10-3 to the windward side of the heat-generating device 30 with greater wind resistance, and dissipates heat on the windward side; the other two paths blow through the first air duct 10-1 and the second air duct 10-2 to the first and second windward sides of the heat-generating device 30, respectively. Since the windward side faces the incoming flow and has high wind resistance, if most of the airflow is forced onto this side using the direct blowing method of existing technology, it will generate a large dynamic pressure loss and require a fan with higher speed and larger flow rate to compensate, thus leading to increased energy consumption and noise. However, this invention pre-divides the airflow through a flow guiding structure, allowing only a small amount of airflow to flow through the central air duct 10-3 to meet the basic cooling needs of the windward side, and guides the main airflow to the first air duct 10-1 and the second air duct 10-2, where the first and second air ducts have lower wind resistance. The Venturi effect structure formed by the gradually narrowing and expanding regions is used to accelerate the heat exchange of this part of the airflow, so that the limited total airflow can be reasonably distributed according to the differences in wind resistance characteristics of the various surfaces of the heat-generating device 30. This achieves better heat dissipation while reducing the total airflow, energy consumption and noise requirements of the system.

[0036] like Figure 3B As shown, along the second direction (Z), the length (L1) of the central air duct 10-3 is greater than the length (L2) of the heating element 30. That is, both ends of the central air duct 10-3 extend beyond the boundary of the heating element 30 along its length direction (the second direction), forming a space for airflow between the heating element 30 and the guide shroud 10 at both ends. After the airflow blows from the air inlet of the central air duct 10-3 towards the windward side of the heating element 30, due to the extra space at both ends of the central air duct 10-3 exceeding the length of the heating element 30, such as... Figure 3B As shown by the curved arrows, after the airflow is locally blocked on the windward side, it diffuses along the second direction to both ends of the heating device 30, bypasses both ends of the heating device 30, and finally exits from the air outlets 103 on both sides of the guide shroud 10, as shown. Figure 4C As shown, the air outlet 103 is a channel set on both sides of the guide shroud 10 along the second direction (Z), which allows the airflow of the central air duct 10-3 to be discharged.

[0037] This embodiment provides a pathway for the obstructed airflow at the windward side to be guided to both ends along the second direction and discharged through the air outlet 103. This reduces the stagnation and backflow of airflow at the windward side, and reduces the ineffective wind resistance loss and energy waste caused by the formation of eddies due to local airflow stagnation. This allows the windward area to obtain orderly and stable airflow. The airflow flowing through the central air duct 10-3 can pass through both ends of the heating device 30 and exchange heat with both ends of the heating device 30, carrying away the heat dissipated from both ends of the heating device 30, which helps to improve the heat dissipation capacity of the heating device 30.

[0038] like Figure 3A As shown, the flow guiding structure of the flow guide shroud 10 specifically includes a flow guide plate 101 and reinforcing ribs 102 located on both sides of the flow guide shroud 10 along the second direction. The reinforcing ribs 102 specifically include transverse reinforcing ribs and vertical reinforcing ribs, which are perpendicular to each other and form an "L" shape.

[0039] The leeward edge of the deflector 101 is the edge furthest from the air inlet, such as... Figure 3B , Figure 4A , Figure 4B As shown, the leeward edge overlaps the windward surface of the heating element 30, thereby separating the first air duct 10-1 from the middle air duct 10-3, and separating the second air duct 10-2 from the middle air duct 10-3. The edge of the reinforcing rib 102 contacts the surface of the heating element 30, and under the constraint of the guide plate 101, the reinforcing rib 102, and the side wall of the guide shroud 10, it limits the heating element 30, preventing it from moving along the first direction and the third direction during assembly and use, and ensuring the stable positional relationship of the first air duct 10-1, the second air duct 10-2, and the middle air duct 10-3 relative to the surfaces of the heating element 30.

[0040] The guide plate 101 and the reinforcing rib 102 work together with the outer surface of the heating device 30 to divide the internal space of the guide shroud 10 into a central air duct 10-3, a first air duct 10-1, and a second air duct 10-2. The guide plate 101 separates the central air duct 10-3 from the first air duct 10-1 and the second air duct 10-2. The reinforcing rib 102 serves to limit the contact of the heating device 30 and fix its installation posture. On the other hand, it works with the side profile of the heating device 30 to limit the flow boundaries of the first air duct 10-1 and the second air duct 10-2.

[0041] Two deflector plates 101 are provided, such as Figure 3B , Figure 4AAs shown, the guide plate 101 is an inclined surface. Two guide plates 101 are inclined relative to each other and enclose each other to form a funnel-shaped gradually expanding area of ​​the central air duct 10-3. That is, the central air duct 10-3 widens from narrow to wide along the airflow direction, forming a funnel shape. The guide plate 101 can be an inclined flat plate, an arc plate, or other irregularly shaped plate. The arc plate can be convex upward or concave downward, as long as the cross-section of the airflow in the central air duct 10-3 gradually increases before reaching the windward surface of the heating device 30. The guide plate 101 makes the central air duct 10-3 form a gradually expanding structure along the airflow direction. The gradually increasing cross-sectional area makes the airflow velocity gradually decrease, reducing the airflow velocity impacting the windward surface and reducing kinetic energy loss.

[0042] The air inlet area of ​​the central air duct 10-3 is smaller than that of the first air duct 10-1, and the air inlet area of ​​the central air duct 10-3 is smaller than that of the second air duct 10-2. This results in the airflow entering the first air duct 10-1 and the second air duct 10-2 being greater than the airflow entering the central air duct 10-3. By setting the relationship between the air inlet areas of the first air duct 10-1, the second air duct 10-2, and the central air duct 10-3, an airflow distribution relationship of "two large airflow paths and one small airflow path" is formed. Since the windward surface corresponding to the central air duct 10-3 has a large wind resistance, allocating a large airflow would cause significant dynamic pressure loss and ineffective wind resistance consumption. Therefore, by reducing the air inlet area of ​​the central air duct 10-3, its airflow proportion is limited from the source. Meanwhile, the flared, gradually expanding structure of the central air duct 10-3 itself allows a smaller amount of airflow to quickly diffuse and cover the entire windward surface, balancing coverage and heat dissipation uniformity. The first air duct 10-1 and the second air duct 10-2 obtain more air volume by virtue of their larger air inlet area. Combined with the aforementioned gradually narrowing and expanding areas, they further accelerate the airflow and improve the heat exchange efficiency. Thus, the limited total air volume is concentrated on the first and second air receiving surfaces, which have lower wind resistance and greater heat exchange potential, thereby improving the overall heat dissipation efficiency.

[0043] Based on the principle that wind resistance is proportional to the square of wind speed, this invention adopts an optimal proportional distribution mechanism to actively allocate a smaller air volume to the windward side with high wind resistance, thereby significantly reducing ineffective wind resistance loss, reducing dependence on large air volume, and avoiding the forced continuous increase of fan power selection.

[0044] like Figure 2 , Figure 3A As shown, the air deflector 10 includes a first air deflector shell 110 and a second air deflector shell 120 that are fixed to each other and are axially symmetrical. The first air deflector shell 110 and the second air deflector shell 120 are mirror-symmetrical about the dividing plane where the central air duct 10-3 is located, and the plane of symmetry is parallel to the XZ plane. In addition, the air deflector 10 can also be divided into two air deflector shells along the second direction, in which case the plane of symmetry is parallel to the XY plane.

[0045] like Figure 2 As shown, the rear parts of the first guide shell 110 and the second guide shell 120 are respectively provided with air outlet ducts 104. The air outlet ducts 104 are arranged in a third direction, and the airflow in the first air duct 10-1 and the second air duct 10-2 is discharged through their respective air outlet ducts 104.

[0046] The first flow guide shell 110 and the second flow guide shell 120 are fixed together by snap-fit ​​connection, such as Figure 2 As shown, the first guide shell 110 has an elastic buckle 111 on its side wall, and the second guide shell 120 has an elastic groove 121 that cooperates with the elastic buckle 111. When the first guide shell 110 and the second guide shell 120 are engaged, the elastic buckle 111 undergoes elastic deformation and engages with the elastic groove 121, achieving reliable closure and fixation between the two. After the first guide shell 110 and the second guide shell 120 are engaged, the guide plates 101 and reinforcing ribs 102 on their respective inner walls work together with the heating element 30 to form the aforementioned first air duct 10-1, second air duct 10-2, and central air duct 10-3. The axially symmetrical split structure connected by buckles facilitates the assembly, disassembly, and maintenance of the heating element 30, and achieves reliable closure of the guide shell 10 without the need for additional fasteners. The structure is simple and the assembly efficiency is high.

[0047] In addition, the first guide shell 110 and the second guide shell 120 can be fixed by means of snap-fit ​​connection, threaded connection, ultrasonic welding, bonding and other detachable or non-detachable connection methods.

[0048] like Figure 4A , Figure 4B As shown, the first air duct 10-1 and the second air duct 10-2 sequentially include a first tapering section S1, a second tapering section S2, a third bend section S3, a fourth widening section S4, a fifth bend section S5, and a sixth straight section S6 along the airflow direction. The first tapering section S1 and the second tapering section S2 are located to the side of the heating device 30 along the first direction, i.e., in the tapering region. The first tapering section S1 and the second tapering section S2 are sequentially distributed along the third direction. As the airflow passes through the first tapering section S1 and the second tapering section S2, the cross-section of the flow channel continuously decreases, and the flow velocity continuously increases, achieving forced convection heat transfer as it passes over the first (or second) air-receiving surface of the heating device 30. The first tapering section S1 is enclosed by the guide plate 101 and the sidewall of the guide shroud 10, and the second tapering section S2 is enclosed by the surface of the heating device 30 and the sidewall of the guide shroud 10. The airflow flows along the third direction within the first tapering section S1 and the second tapering section S2.

[0049] The fourth expanding section S4, the fifth turning section S5, and the sixth straight section S6 are located behind the heating device 30 along a third direction. The fourth expanding section S4 is a gradually expanding region, and one end of the sixth straight section S6 is connected to the external environment. The fourth expanding section S4 is formed by the surface of the heating device 30 and the side wall of the air guide shroud 10. The fifth turning section S5 is formed by the surface of the heating device 30 and the side wall of the air outlet duct 104, and the sixth straight section S6 is formed by the side wall of the air outlet duct 104.

[0050] After the airflow accelerates through the first tapering section S1 and the second tapering section S2 and passes over the side of the heating element 30, it turns at the third turning section S3 (changing from a third direction to a first direction), bypasses the rear edge of the heating element 30, and enters the fourth expanding section S4 with a gradually increasing cross-section to reduce friction loss. It then turns again at the fifth turning section S5 (changing from a first direction to a third direction), and finally exits the rear of the guide shroud 10 through the sixth straight section S6 in a third direction. This six-segment flow channel structure assigns the functions of accelerated heat exchange, turning and bypassing, drag reduction and diffusion, and smooth discharge to different flow channel segments, ensuring that the airflow maintains an orderly flow throughout its passage over the side and rear of the heating element 30, reducing local turbulence and backflow vortices, and further reducing ineffective wind resistance loss.

[0051] like Figure 4A , Figure 4B As shown, the outer contour of the flow deflector 10 has a tapering region along a third direction, that is, the outer contour of the flow deflector 10 gradually narrows along the overall airflow direction (third direction). In the embodiment shown in the accompanying drawings of this application, the width of the entire flow deflector 10 along the second direction remains consistent from front to back, and only the height along the first direction changes, forming a contracting structure in which the height gradually decreases along the third direction.

[0052] The tapered outer contour design of the air guide 10 is adapted to the tapered and expanded areas of the first air duct 10-1 and the second air duct 10-2 inside the air guide 10, making the overall structure of the air guide 10 more compact and reducing the equipment installation space.

[0053] like Figure 5A , Figure 5B , Figure 5C , Figure 5D As shown, the present invention also provides a heat sink, including the above-mentioned multi-channel airflow guide shroud and a fan 20. The fan 20 is disposed at the air inlets of the first airflow 10-1, the second airflow 10-2, and the middle airflow 10-3, and is used to deliver airflow into the airflow guide shroud 10. Figure 5DThis is an exploded view of the heat sink in this embodiment, showing the assembly relationship between the fan 20, the first airflow guide shell 110, the second airflow guide shell 120, the heat-generating device 30, and the bracket 40. This heat sink integrates the airflow guide shell 10 and the fan 20 into one unit, and can be installed as an independent component near the heat-generating device 30 in application scenarios such as high-voltage boxes in energy storage systems, achieving the zoned and differentiated heat dissipation effects described in the aforementioned embodiments.

[0054] like Figure 5D As shown, the fan 20 includes a central vortex region 210 and a blade portion 220. The central vortex region 210 has no effective airflow output when rotating, while the blade portion 220 generates airflow after rotation. After the fan 20 is installed, its central vortex region 210 is directly opposite the middle area of ​​the central air duct 10-3, so the central air duct 10-3 is only allocated a small amount of airflow.

[0055] The bracket 40 is made of sheet metal bending. The bracket 40 body has four through holes. Fasteners pass through the through holes of the bracket 40 and the mounting through holes of the fan 20 in sequence, and are fastened to the corresponding threaded holes on the air guide 10, thereby fixing the fan 20 and the air guide 10 as a whole onto the bracket 40.

[0056] In use, the heating element 30 is first installed in the mounting position inside the air guide shroud 10. The first air guide shell 110 and the second air guide shell 120 of the air guide shroud 10 are connected to the outer surface of the heating element 30 through the air guide plate 101 and the reinforcing rib 102 and are closed by snap-fit ​​connection, so that the internal space of the air guide shroud 10 is divided into an independent first air duct 10-1, a second air duct 10-2 and a middle air duct 10-3. Then, the fan 20 is installed at the air inlet of the first air duct 10-1, the second air duct 10-2 and the middle air duct 10-3. After the fan 20 is started, the airflow is split by the guide plate 101: a larger proportion of the airflow enters the first air duct 10-1 and the second air duct 10-2 respectively, and after being accelerated by the first tapering section S1 and the second tapering section S2, it passes over the first and second air receiving surfaces of the heating device 30 for efficient heat exchange, and then passes through the third turning section S3, the fourth expanding section S4 and the fifth turning section S5 to reduce drag and change direction, and finally passes through the sixth straight section S6 to be discharged from the rear of the guide shroud 10 along the third direction; a smaller proportion of the airflow enters the middle air duct 10-3, and is blown towards the windward surface of the heating device 30 by the funnel-shaped expanding area formed by the guide plate 101, and then passes around the two ends of the heating device 30 along the second direction and is discharged from the air outlets 103 on both sides of the guide shroud 10. By rationally allocating the total air volume through the aforementioned air duct structure and controlling the local flow velocity through the Venturi effect, an overall heat dissipation effect is achieved while taking into account the differentiated heat dissipation needs of the 30 surfaces of the heat-generating devices, under the conditions of low total air volume, low fan energy consumption and low noise.

[0057] The first air duct 10-1 and the second air duct 10-2 correspond to the first and second air-receiving surfaces of the heating device 30, respectively. The overall flow path has low flow resistance, providing the basic conditions for airflow acceleration. After entering the first air duct 10-1 and the second air duct 10-2, the airflow enters the contracting region under the guidance of the guide plate 101 and the contracting surface of the guide shroud 10 itself. According to the principle of continuity of incompressible fluids (airflow = cross-sectional area × velocity), the cross-section gradually decreases, and the velocity continuously and rapidly increases. At the limit position of the contracting region, the velocity in the air duct reaches its maximum, and the forced convection heat transfer efficiency between the first and second air-receiving surfaces of the heating device 30 and the air duct is significantly improved.

[0058] Due to frictional resistance within the flow guide, the maximum flow velocity corresponding to this extreme position has a limit value, which is determined by the control method described later. Beyond this limit, if the cross-section of the narrow flow channel is too small, it will result in significant resistance loss. Therefore, the air duct enters a gradually widening zone to maintain the overall flow velocity, utilizing the accelerated high-speed airflow to quickly and substantially remove heat from the upper surface and part of the rear surface, and the lower surface and part of the rear surface of the heat-generating device 30. The airflows of the first air duct 10-1 and the second air duct 10-2 are isolated by the outlet duct 104 before being discharged; the two airflows are independent and do not interfere with each other.

[0059] This invention also provides a control method for the multi-duct fairing of this invention. The method is applied to the aforementioned multi-duct fairing and is used to calculate some design parameters of the fairing, including: Determine the cross-sectional areas of the air inlets of the first air duct 10-1, the second air duct 10-2, and the middle air duct 10-3; along the first direction (Y), the air inlet of the middle air duct 10-3 is located between the air inlets of the first air duct 10-1 and the second air duct 10-2; the first air duct 10-1 and the second air duct 10-2 are used to guide the airflow to the first wind-receiving surface and the second wind-receiving surface.

[0060] Define the tapering ratio of the tapering regions of the first air duct 10-1 and the second air duct 10-2; the tapering ratio is the ratio of the area from the air inlet to the narrowest point of the cross-sectional area of ​​the inner cavity of the first air duct 10-1 and the second air duct 10-2. If the first air duct 10-1 and the second air duct 10-2 are axially symmetrically distributed, then the first air duct 10-1 and the second air duct 10-2 are set with the same air inlet size and tapering ratio. The first air duct 10-1 and the second air duct 10-2 also adopt independently set air inlet areas and tapering ratios.

[0061] Based on the tapering ratio, design the tapering regions of the first air duct 10-1 and the second air duct 10-2.

[0062] Furthermore, the first air duct 10-1 and the second air duct 10-2 are also provided with expanding regions, which are located after the contracting regions. The size ratio of the contracting regions of the first air duct 10-1 and the second air duct 10-2 and the expanding regions located after the contracting regions is determined to achieve the best heat dissipation effect for the heat-generating device 30.

[0063] The size ratios of the contracting and expanding regions can be obtained through various methods, such as creating models with different size ratios and conducting experiments, using software simulation, or establishing and calculating mathematical models. Through experiments, simulations, and mathematical model calculations, the optimal solution can be determined by comparing the steady-state temperatures of different schemes, with the scheme exhibiting the lowest steady-state temperature.

[0064] The following provides a method for calculation by establishing a mathematical model: First, establish a fluid dynamics model for either the first air duct 10-1 or the second air duct 10-2, as well as the central air duct 10-3. Since the first air duct 10-1 and the second air duct 10-2 have symmetrical structures and the same airflow pattern, it is sufficient to model one of them as an example.

[0065] Based on the above fluid dynamics model, initial parameters are input, including but not limited to initial environmental parameters, fluid characteristic parameters, structural parameters, and the selected fan PQ curve. Based on the obtained flow rate Qside in the central duct and Qmain in the first or second duct, the fan static pressure Pfan,provide corresponding to the current total flow rate is further calculated. The specific process is as follows: like Figure 8 As shown, input the initial environmental parameters, fluid characteristic parameters, structural parameters, and selected fan PQ curve, etc.

[0066] In Matlab, the fzero function is called. This function is based on a hybrid algorithm mechanism of interval bisection and inverse quadratic interpolation. It takes a pressure value Pguess that is less than the maximum static pressure output by the fan, and according to the law of equal pressure drop in parallel flow networks, it sets Pguess=Pmain=Pside, and enters the outer logic iteration.

[0067] Based on the outer logic iteration, let Pguess = Pside, and the flow rate Qside through the central air duct is obtained by analytical calculation.

[0068] Based on the outer logic iteration, let Pguess = Pmain, and then enter the inner logic iteration.

[0069] Based on the inner iteration structure, assuming a trial value Qguess is substituted into the equation Pmain=Pmain(Qguess), when the error Pguess-Pmain(Qguess) is sufficiently small, output Qmain=Qguess and exit the inner iteration.

[0070] Based on the obtained flow rates Qside in the central duct and Qmain in the first / second duct, the static pressure Pfan,provide corresponding to the current total flow rate is calculated. When the error Pguess - Pfan,provide is sufficiently small, P = Pguess and Q = Qtotal are output, and the loop exits.

[0071] Secondly, a heat transfer model is established, and a set of heat-fluid coupling equations is constructed to calculate the steady-state temperature of the heating device 30 when it reaches thermal equilibrium. The heat transfer model includes the convective heat transfer coefficients of the air-receiving surface (i.e., the surface facing the airflow direction in the first or second air-receiving surface) and the leeward surface (the surface facing away from the airflow inflow direction) of the heating device 30, calculated based on the Reynolds number and Prandtl number. The airflow velocity is higher and the heat transfer coefficient is larger in the air-receiving surface region corresponding to the first converging section S1 and the second converging section S2, while the airflow velocity is relatively lower and the heat transfer coefficient is correspondingly smaller in the leeward surface region corresponding to the fourth expanding section S4. Both can be obtained from the Nusselt number and the local height of the flow channel, respectively. Then, based on the above convective heat transfer coefficients, the air-receiving surface area and the leeward surface area of ​​the heating device 30, and the temperature difference between the steady-state temperature of the heating device 30 when it reaches thermal equilibrium and the ambient temperature, the total heat transfer of the first air duct 10-1 and the second air duct 10-2 is calculated. When performing optimization iterations, there must be an objective function. The steady-state temperature T is the most suitable parameter for the objective function. A decrease in the steady-state temperature T indicates that the optimization is effective; otherwise, it is ineffective.

[0072] Based on the established fluid dynamics model and heat transfer model, the heating power of the heating device 30 is equal to the total heat exchange, and the steady-state temperature of the heating device 30 when it reaches thermal equilibrium can be obtained. Keeping the inlet size of the tapered region unchanged, the outlet size of the tapered region is used as the independent variable for parameter scanning to generate a tapered ratio-steady-state temperature correlation curve with convex function characteristics. The size ratio corresponding to the global minimum point of the curve is extracted and determined as the optimal tapered ratio.

[0073] Subsequently, keeping the inlet size of the expanding region constant, the outlet size of the expanding region is used as the independent variable for parameter scanning to generate the expansion ratio-steady-state temperature correlation curve. The size ratio corresponding to the global minimum point of the expansion ratio-steady-state temperature correlation curve is determined as the optimal expansion ratio.

[0074] Finally, based on the obtained optimal shrinkage ratio and optimal expansion ratio, the specific dimensions of the shrinkage and expansion regions in the first air duct 10-1 and the second air duct 10-2 are set so that the shroud 10 has the best heat dissipation effect on the heat-generating device 30 under this size combination.

[0075] The above control method combines the hydrodynamic principle of the Venturi effect with the heat transfer calculation of the heating device 30, providing a quantifiable and iterative theoretical basis for the size design of the shrinking and expanding regions, avoiding problems such as long design cycles and unstable heat dissipation effects caused by relying on trial and error.

[0076] The process of changing the size ratio of the contracting and expanding regions and calculating the steady-state temperature in the above control method can be achieved through iterative computer programming. The above fluid dynamics model and heat transfer model can be numerically iteratively solved using a computer.

[0077] The control method of the present invention is derived in detail below, including three processes: global flow field calculation, global temperature field calculation, and determination of the optimal contraction / expansion ratio. 1. Global flow field calculation Based on the multi-channel structure of this invention, after the fluid enters the air guide shroud via the fan, it is divided into four parts, such as... Figure 6A , Figure 6B The first part corresponds to the first air duct 10-1, the second part corresponds to the second air duct 10-2, and the third and fourth parts correspond to the middle air duct 10-3.

[0078] For ease of explanation, the following will use Figure 6A The orientation shown is as follows: the first part corresponds to the upper airflow duct, the second part to the lower airflow duct, the third part to the left airflow duct, and the fourth part to the right airflow duct. The heating element 30 is referred to as a fuse.

[0079] In the first part, the external gas passes through a converging section, reaches the upper surface of the fuse, and accelerates as it passes over it, exchanging heat with the fuse and ultimately carrying away the heat. The second part is similar to the first, with the gas passing over the lower surface of the fuse, carrying away heat. In the third part, the gas first impacts the front of the fuse, its speed instantly decreasing, and most of its kinetic energy is converted into pressure potential energy, forming a local high-pressure stagnation point with significant local resistance. The impacted air is forced to disperse and then regroup, bypassing the right-angled edge of the fuse and entering the left side. It then escapes from the air outlet on the left side of the diffuser, carrying heat into the external environment. The fourth part is similar to the third, with the gas passing over the right side of the fuse and entering the external environment from the air outlet on the right side of the diffuser.

[0080] During this process, the air volume and static pressure output by the fan gradually stabilize. When a steady state is reached, based on the conservation of flow rate, the flow rate Q and pressure drop P of the parallel air duct should satisfy equations (1) and (2).

[0081] (1)

[0082] In the formula, The total air volume output by the fan is m^3 / s; The total air volume inside the air deflector is m³ / s; The volumetric flow rate of the first part (upwind duct) or the second part (downwind duct) is expressed in m³ / s. The volumetric flow rate, in m³ / s, refers to the volumetric flow rate of the third section (left side duct) or the fourth section (right side duct).

[0083] (2)

[0084] In the formula, This indicates the static pressure of the fan, in Pa; This represents the pressure drop caused by the upper / lower air duct, in Pa; This indicates the pressure drop caused by the left / right air duct, in Pa.

[0085] For the fan, based on the static pressure-flow characteristic curve, the PQ equation is obtained by polynomial fitting, as shown in equation (3).

[0086] (3)

[0087] In the formula, a, b, c, d, and e are all fitting coefficients.

[0088] 1.1 Calculation of pressure drop in upper / lower ducts

[0089] like Figure 4A As shown, taking the upper air duct as an example, the fluid flow structure can be divided into the following six parts: 1. Pre-acceleration section (corresponding to the first contraction section S1 mentioned above); 2. Upper surface windward section (corresponding to the second contraction section S2 mentioned above); 3. First turning section (corresponding to the third turning section S3 mentioned above); 4. Rear surface leeward section (corresponding to the fourth expansion section S4 mentioned above); 5. Second turning section (corresponding to the fifth turning section S5 mentioned above); 6. Straight outlet section (corresponding to the sixth straight section S6 mentioned above).

[0090] Incompressible fluids follow the continuity equation within a cavity, therefore the flow rate is equal at all cross-sections within the pipe, as given by equation (4). (4) In the formula, the subscript Any cross section of the upper / lower air duct; , They refer to Wind speed and height at the cross-section; W refers to the width of the cross-section, in meters.

[0091] Since the widths of all sections are equal, equation (4) can also be written as: (5) In the formula, q is the linear volumetric flow rate. , m^2 / s.

[0092] In the pre-acceleration section, a small element segment can be taken to obtain the local pressure drop, as shown in equation (6). (6) In the formula, For the first section of friction pressure drop, Pa; f is the friction drag coefficient, which is determined by the Reynolds number Re, see equations (7) and (8); The hydraulic diameter is taken as twice the height in this structure. , m; ρ is the fluid density, kg / m^3; v is the velocity, see equation (5), m / s.

[0093] (7) (8) In equation (8), μ is the fluid dynamic viscosity, which is taken as 1.96×10^(-5).

[0094] right Integrating the equations, we obtain the total pressure drop generated by the fluid in the first segment, as shown in equation (9). (9) In the formula, Let be the projected distance (m) of the total length of the first section of the upwind passage on the x-axis; , These are the heights of the first entrance and the first exit (and the second entrance), respectively, in meters (m).

[0095] Similarly, calculate the total voltage drop in the second segment: (10) In the formula, Let be the projected distance (m) of the total length of the second section of the upwind passage on the x-axis; , These are the heights at the second entrance (and the first exit) and the second exit, respectively, in meters.

[0096] airflow When the velocity at the cross section reaches its maximum value, the fluid impacts the edge and deflects downwards, causing streamline separation and generating a separation vortex, resulting in a large local impact resistance, as shown in equation (11).

[0097] (11)

[0098] In the formula, The local resistance coefficient for the third segment is set to 1.

[0099] After the air turns and regroups at the corner, it enters the fourth segment: (12) In the formula, Let be the projected distance of the total length of the fourth segment in the Z direction, in meters. , These are the heights at the entrance and exit of the fourth section, respectively, in meters (m).

[0100] airflow upon arrival At the cross-section, after turning the corner again, the flow direction changes and enters... The channel generates significant local resistance. (13) In the formula, The local resistance coefficient for the fifth segment is set to 1.2. The height of the sixth straight segment is in meters (m).

[0101] Finally, the fluid flows through the sixth straight section, carrying away heat and escaping into the external environment, as shown in equation (14).

[0102] (14)

[0103] In the formula, Let be the length of the straight section at the exit, in meters (m).

[0104] At this point, the total pressure drop in the upper / lower air ducts can be calculated: (15) 1.2 Calculation of pressure drop in left / right ducts The total pressure drop of the left / right ducts is calculated using the lumped parameter method, as shown in equation (16). (16) In the formula, The local resistance coefficient for the left / right air duct is taken as 2.5; The airflow rate in the left / right duct is measured in m³ / s. The total area of ​​the left / right air outlet is 103, in m^2.

[0105] The above analysis shows that the total pressure drop of the fluid inside the flow guide mainly depends on the flow channel structure and the fan output air volume.

[0106] This invention constructs parallel coupled equations for solving fluid dynamics problems. The upper / lower air ducts obey a six-segment nonlinear impedance characteristic. = The left and right air ducts follow the throttling impedance characteristics. = According to the law of equal voltage drop in parallel current networks, the steady-state operating point of the system strictly satisfies: .

[0107] This calculation model uses nonlinear iterative root-finding to simultaneously and analytically determine the actual working static pressure of the system. And the actual flow rate allocated to the upper / lower and left / right air ducts. and Due to the throttling resistance coefficients of the left and right face holes. The coefficient is much larger than the total resistance coefficient of the upper / lower air ducts. The solution results quantitatively confirm the physical optimization characteristics of the system's total flow rate being automatically and highly concentrated in the core heat exchange area of ​​the main air duct.

[0108] 2. Global Temperature Field Calculation

[0109] 2.1 Calculation of temperature field in upper / lower ducts

[0110] In the temperature field of the upper / lower air duct, the flow channel is divided into an air-receiving surface (upper surface / lower surface) and a leeward surface, corresponding to the XOY and ZOY surfaces of the fuse, respectively, as follows. Figure 4A As shown.

[0111] On the windward side, consider a small element dx, then the convective heat transfer coefficient is: (17) In the formula, For Nusselt number, which is a dimensionless number, see equation (18). k is the thermal conductivity of the fluid, taken as 0.0283.

[0112] (18)

[0113] In the formula, Re is the Reynolds number, see formula (8); Pr is the Prandtl number, which is 0.71.

[0114] The convective heat transfer coefficient is related to the local fluid velocity. Integrating over the interval with respect to dh yields the average convective heat transfer coefficient of the windward surface. See equation (19).

[0115] (19)

[0116] Similarly, the average convective heat transfer coefficient on the leeward side can be obtained. See equation (20).

[0117] (20)

[0118] The total heat exchange in the upper / lower air ducts is: (twenty one) In the formula, The area of ​​the fuse's wind-receiving surface is m². is the area of ​​the leeward side of the fuse, m^2; T is the steady-state temperature of the fuse when it reaches thermal equilibrium, K; The ambient temperature is in K.

[0119] 2.2 Calculation of temperature field in left / right air ducts

[0120] In this invention, the airflow undergoes stagnation impact and porous throttling in the exhaust area on the side of the guide shield, exhibiting complex three-dimensional discrete flow separation characteristics. When air escapes from the side, it is constrained by the presence of the exhaust holes, affecting the airflow allocated to the left / right ducts. The lumped parameter method is used to perform equivalent convective heat transfer calculations.

[0121] (twenty two)

[0122] In the formula, The total area of ​​the left / right air outlet is 103, in m^2.

[0123] (twenty three)

[0124] In the formula, Let the hydraulic diameter be taken as... ,m; (twenty four) Based on the above, the convective heat transfer coefficients of the left / right air ducts are derived. : (25) The total heat exchange of the left / right air ducts is: (26) In the formula, Let be the area of ​​one side of the fuse, in m^2.

[0125] In summary, the total heat exchanged by the fan to the fuse is: (27) Let the fuse's heating power P equal the total heat exchange ф, and derive the steady-state temperature T: (28) In this embodiment, the steady-state temperature of the fuse is calculated to be 89.21℃, as shown in Table 1 below.

[0126] Table 1 Air Volume And the calculated steady-state temperature T:

[0127] 3. Optimal taper / expansion ratio

[0128] This invention discloses a multi-channel airflow-guided heat dissipation structure. This structure aims to constrain the fan streamline and achieve optimal flow distribution and heat dissipation by adjusting and reducing system air resistance. Based on the pressure drop and heat transfer mathematical calculation model established above, the steady-state temperature of internal components at thermal equilibrium can be obtained. Furthermore, this paper establishes a heat-flow coupled multi-objective optimization algorithm and finds the optimal taper ratio through iterative single-variable control. With optimal spread ratio This provides theoretical guidance for the design of the fairing.

[0129] The fluid dynamic characteristics of the upper / lower air ducts are analyzed, and with... As the flow rate decreases, the local velocity of the fluid in the converging pipe increases, intensifying the scouring of the boundary layer on the fuse's air-receiving surface and significantly increasing the convective heat transfer coefficient. However, at the same time, the system's flow resistance also increases, leading to a decrease in the total air intake. The temperature drops, preventing heat from being dissipated in time. Therefore, there exists an optimal design where... When the optimal solution is reached, the convective heat transfer from the windward side of the upwind duct reaches its maximum value. Similarly, There also exists an optimal solution that maximizes the value of the leeward side of the upwind road.

[0130] First, maintain Unchanged, will Substitute the values ​​sequentially into the calculation, and output the steady-state temperature T as the result. Figure 7A The curves showing the coupling between the windward surface shrinkage ratio and the steady-state temperature of the system are presented.

[0131] Then keep Unchanged, will Substitute the values ​​sequentially into the calculation, and output the steady-state temperature T as the result. See... Figure 7B This demonstrates the coupling curve between the leeward spread ratio and the system steady-state temperature.

[0132] Based on the iteration results, when =3.13、 When the temperature is 1, the heat dissipation effect is the best, at which point T = 87.94℃.

[0133] In summary, the multi-channel airflow guide and heat sink provided by this invention, by constructing independent first airflow channels 10-1, second airflow channels 10-2, and central airflow channels 10-3 inside the airflow guide 10, and combining them with guide plates 101 and reinforcing ribs 102 to divert and guide airflow, achieves differentiated airflow distribution based on the different surface resistance characteristics of the heat-generating device 30; by setting tapered and expanding regions in the first airflow channels 10-1 and second airflow channels 10-2, the Venturi effect is used to accelerate heat exchange of airflow while reducing drag, improving the heat dissipation efficiency of the side of the heat-generating device 30; through the trumpet-shaped expanding structure of the central airflow channel 10-3 and the air outlet 103 along the second direction, the basic cooling requirements of the windward surface with high wind resistance are taken into account, while the orderly discharge of airflow is achieved, reducing ineffective wind resistance loss and the generation of turbulent eddies. The axisymmetric, snap-fit ​​split airflow guide 10 structure takes into account both assembly efficiency and structural reliability.

[0134] This invention can effectively reduce ineffective wind resistance loss and reduce reliance on large air volumes; it enables differentiated air supply based on wind resistance characteristics, thereby improving heat dissipation efficiency; the flow channel is divided, the airflow direction is clear, and there is no overall turbulence or eddies.

[0135] This invention also provides a control method based on fluid dynamics and heat transfer models to iteratively solve for the optimal size ratio of the contracting and expanding regions, thereby achieving the best heat dissipation effect and providing a theoretical basis for the engineering implementation of the solution.

[0136] The above description of the disclosed embodiments enables those skilled in the art to make or use the invention. Various modifications to these embodiments will be readily apparent to those skilled in the art, and the general principles defined herein may be implemented in other embodiments without departing from the spirit or scope of the invention. Therefore, the invention is not to be limited to the embodiments shown herein, but is to be accorded the widest scope consistent with the principles and novel features disclosed herein.

Claims

1. A multi-channel airflow guide shroud for dissipating heat from a heat-generating device (30), characterized in that, include: A flow guide (10) is provided inside the flow guide (10) for mounting the heating device (30); The air guide shroud (10) is provided with an air guide structure inside, which divides the internal space of the air guide shroud (10) into a first air duct (10-1), a second air duct (10-2), and a middle air duct (10-3) that are independent of each other; along the first direction, the air inlet of the middle air duct (10-3) is located between the air inlet of the first air duct (10-1) and the air inlet of the second air duct (10-2); the air inlets of the first air duct (10-1), the second air duct (10-2), and the middle air duct (10-3) are used to install fans (20). The first air duct (10-1) is used to guide airflow to the first air-receiving surface of the heating device (30), and the second air duct (10-2) is used to guide airflow to the second air-receiving surface of the heating device (30); the first air-receiving surface and the second air-receiving surface are opposite to each other and are both surfaces adjacent to the windward surface of the heating device (30); the airflow entering the first air duct (10-1) and the second air duct (10-2) bypasses the first air-receiving surface and the second air-receiving surface of the heating device (30) respectively, and is discharged from the rear of the guide shroud (10); Both the first air duct (10-1) and the second air duct (10-2) are provided with a gradually narrowing region and a gradually expanding region in sequence along the airflow direction. The cross-section of the flow channel in the gradually narrowing region gradually decreases along the airflow direction, and the cross-section of the flow channel in the gradually expanding region gradually increases along the airflow direction. The central air duct (10-3) is used to guide the airflow toward the windward side of the heating device (30).

2. The multi-channel air guide shroud according to claim 1, characterized in that, Along the second direction, the length of the central air duct (10-3) is greater than the width of the heating device (30); The central air duct (10-3) guides the airflow toward the windward side of the heating device (30). After the airflow passes around both ends of the heating device (30) along the second direction, it is discharged from the air outlets (103) on both sides of the guide shroud (10).

3. The multi-channel air guide shroud according to claim 2, characterized in that, The flow guiding structure includes a flow guiding plate (101) and reinforcing ribs (102) located on both sides of the flow guiding shroud (10) along the second direction. The leeward edge of the deflector plate (101) overlaps the windward side of the heating device (30), and the reinforcing rib (102) is used to contact and limit the heating device (30) so as to cooperate with the heating device (30) to divide the internal space of the deflector to form the central air duct (10-3), the first air duct (10-1) and the second air duct (10-2).

4. The multi-channel air guide shroud according to claim 3, characterized in that, The guide plate (101) is an inclined surface, and the two guide plates (101) together form the funnel-shaped gradually expanding area of ​​the central air duct (10-3); The air inlet area of ​​the central air duct (10-3) is smaller than the air inlet area of ​​the first air duct (10-1) and smaller than the air inlet area of ​​the second air duct (10-2), so that the air volume entering the first air duct (10-1) and the second air duct (10-2) is greater than the air volume entering the central air duct (10-3).

5. The multi-channel air guide shroud according to claim 3, characterized in that, The flow guide (10) includes a first flow guide shell (110) and a second flow guide shell (120) that are fixed to each other and are axially symmetrical. The first flow guide shell (110) and the second flow guide shell (120) are fixed by snap-fit ​​connection.

6. The multi-duct air guide shroud according to any one of claims 1-5, characterized in that, The first air duct (10-1) and the second air duct (10-2) sequentially include the following along the airflow direction: First narrowing section, second narrowing section, third turning section, fourth widening section, fifth turning section, sixth straight section; The first tapering section and the second tapering section are located on the side of the heating device (30) along the first direction; the fourth expanding section, the fifth turning section, and the sixth straight section are located on the rear of the heating device (30) along the third direction.

7. The multi-channel air guide shroud according to claim 6, characterized in that, The outer contour of the fairing (10) has a tapering region along a third direction.

8. A radiator, characterized in that, The multi-duct air deflector as described in any one of claims 1-7, and: A fan (20) is installed at the air inlet of the first air duct (10-1), the second air duct (10-2), and the middle air duct (10-3) to deliver airflow into the shroud (10).

9. A control method, characterized in that, The multi-duct air guide cover according to any one of claims 1-7 comprises: Determine the cross-sectional area of ​​the air inlets of the first air duct (10-1), the second air duct (10-2), and the middle air duct (10-3); along the first direction, the air inlet of the middle air duct (10-3) is located between the air inlet of the first air duct (10-1) and the air inlet of the second air duct (10-2); Set the shrinkage ratio of the shrinkage regions of the first air duct (10-1) and the second air duct (10-2); According to the tapering ratio, the tapering regions of the first air duct (10-1) and the second air duct (10-2) are designed; the first air duct (10-1) is used to guide the airflow to the first wind-receiving surface of the heating device (30), and the second air duct (10-2) is used to guide the airflow to the second wind-receiving surface of the heating device (30); the middle air duct (10-3) is used to guide the airflow to blow towards the windward surface of the heating device (30).

10. The control method according to claim 9, characterized in that, Determine the size ratio of the tapering regions of the first air duct (10-1) and the second air duct (10-2) to the expanding region following the tapering regions: Establish a fluid dynamics model for the first air duct (10-1) or the second air duct (10-2), and the middle air duct (10-3); based on the fluid dynamics model, input initial parameters, including: initial environmental parameters, fluid characteristic parameters, structural parameters, and the selected fan PQ curve; based on the solved middle air duct flow rate Qside and the first or second air duct flow rate Qmain, continue to solve for the fan static pressure Pfan,provide corresponding to the current total flow rate; A heat transfer model is established, a set of heat flow coupling equations is constructed, and the steady-state temperature of the heating device (30) when it reaches thermal equilibrium is calculated. Based on the fluid dynamics model and the heat transfer model, the steady-state temperature of the heating device (30) when it reaches thermal equilibrium is calculated; Keeping the inlet size of the contracting region constant, the outlet size of the contracting region is used as the independent variable for parameter scanning to generate a contraction ratio-steady-state temperature correlation curve. The size ratio corresponding to the global minimum point of the contraction ratio-steady-state temperature correlation curve is determined as the optimal contraction ratio. Keeping the inlet size of the expanding region constant, the outlet size of the expanding region is used as the independent variable for parameter scanning to generate a expanding ratio-steady-state temperature correlation curve. The size ratio corresponding to the global minimum point of the expanding ratio-steady-state temperature correlation curve is determined as the optimal expanding ratio. The dimensions of the tapered region and the expanded region are set according to the optimal tapering ratio and the optimal expanding ratio.

11. The control method according to claim 10, characterized in that, The fluid dynamics model includes formulas for calculating the local pressure drop of each segment as the airflow passes through the first converging segment, the second converging segment, the third turning segment, the fourth expanding segment, the fifth turning segment, and the sixth straight segment. The sum of the local pressure drops of each segment is the total pressure drop of the first air duct (10-1) or the second air duct (10-2).

12. The control method according to claim 10 or 11, characterized in that, The heat transfer model includes the convective heat transfer coefficients of the windward and leeward sides of the heating device (30) calculated based on the Reynolds number and Prandtl number, and the total heat transfer of the first air duct (10-1) and the second air duct (10-2) calculated based on the convective heat transfer coefficients, the windward and leeward areas of the heating device (30), and the temperature difference between the steady-state temperature of the heating device (30) and the ambient temperature when it is in thermal equilibrium.

Images