Multi-branch parallel skin runner and design method thereof

Abstract

The invention relates to a multi-branch parallel skin runner and a design method thereof, belongs to the technical field of electronic heat dissipation of aircrafts, and solves the problems of large occupied space and large flow resistance of cold source equipment in an existing aircraft heat dissipation system. A multi-branch parallel skin flow channel is arranged in skin and comprises a flow channel inlet, a flow channel outlet, a first medium flow channel, a second medium flow channel, a third medium flow channel, a first collecting flow channel and a second collecting flow channel. The three medium flow channels are U-shaped flow channels; in the width direction of the skin, the first medium flow channel, the second medium flow channel and the third medium flow channel are sequentially nested and arranged in parallel from the edge to the center; the first collecting flow channel and the second collecting flow channel are symmetrically arranged on the two sides of the U-shaped opening end; one ends of the three medium flow channels are gathered through a first gathering flow channel and are communicated with one another; the other ends of the three medium flow channels are gathered through a second gathering flow channel and are communicated with one another; the multi-branch parallel skin runner is applied to cold source equipment, and is small in space and low in flow resistance.

Description

Technical Field

[0001] The present invention relates to the technical field of electronic heat dissipation for aircraft, and particularly to a multi-branch parallel skin flow channel and a design method thereof. Background Art

[0002] With the continuous improvement of the working efficiency of modern aircraft, the electronic devices inside the aircraft, such as navigation systems and control systems, are facing more severe working conditions. First, the continuous improvement of working performance (such as detection range, resolution, etc.) makes the power consumption of the devices continue to increase; second, the design of the aircraft platform tends to be lightweight and miniaturized, resulting in higher device integration and further increased heat flux density; third, with the increase of the flight time of the aircraft, the electronic devices face longer working hours. In summary, the aircraft platform is facing the severe challenges of high power consumption, long working hours, and high heat flux density.

[0003] The existing thermal control measures for aircraft platforms generally use two types of technologies. One is the passive cooling measure based on phase change materials, and its disadvantage is that this passive consumable cold source can only support the device to work for a limited time; the other is the use of compression refrigeration, and its disadvantage is that it consumes a huge amount of electric energy and has a large volume and mass itself.

[0004] Therefore, it is of great significance to design a cold source device that can be applied to the heat dissipation system of the aircraft platform, which can simultaneously meet the requirements of small space occupied by the aircraft platform by the heat dissipation system, long continuous working time, small flow resistance under high heat flux density, and large heat dissipation area under the conditions of high heat transfer and low flow resistance. Summary of the Invention

[0005] In view of the above analysis, the embodiments of the present invention aim to provide a multi-branch parallel skin flow channel and a design method thereof, so as to solve the problems that the cold source device of the heat dissipation system occupies a large space on the aircraft platform and has a large flow resistance when the existing aircraft platform works under high power, long working hours, and high heat flux density.

[0006] The object of the present invention is mainly achieved by the following technical solutions:

[0007] On the one hand, the present invention provides a multi-branch parallel skin flow channel, which is arranged in the skin and includes a flow channel inlet, a flow channel outlet, a first medium flow channel, a second medium flow channel, a third medium flow channel, a first converging flow channel, and a second converging flow channel;

[0008] The first medium flow channel, the second medium flow channel, and the third medium flow channel are "U"-shaped flow channels;

[0009] Along the width direction of the skin, the first medium flow channel, the second medium flow channel, and the third medium flow channel are nested and arranged in parallel in sequence from the edge to the center;

[0010] The first converging channel and the second converging channel are symmetrically arranged on both sides of the "U"-shaped opening end;

[0011] One ends of the first medium channel, the second medium channel and the third medium channel converge through the first converging channel and are interconnected; the other ends of the first medium channel, the second medium channel and the third medium channel converge through the second converging channel and are interconnected;

[0012] The channel inlet is located on the side of the first converging channel and is connected to the first converging channel; the channel outlet is located on the side of the second converging channel and is connected to the second converging channel.

[0013] Further, the cross-sections of the first medium channel, the second medium channel and the third medium channel facing the "U" opening are rectangles, and the sides of the rectangles are transitioned by rounded corners.

[0014] Further, the radius of the rounded corner of the rectangle satisfies:

[0015] R’ = 1 / 2 * min(W, H);

[0016] where, W is the width of the cross-sectional rectangle of the medium channel, in mm;

[0017] H is the height of the cross-sectional rectangle of the medium channel, in mm;

[0018] R’ is the radius of the rounded corner of the cross-sectional rectangle of the medium channel, in mm.

[0019] Further, the distances between the first medium channel, the second medium channel and the third medium channel are equal.

[0020] Further, the distance between the first medium channel, the second medium channel and the third medium channel satisfies 1 / 2 * W ≤ K ≤ 3 / 4 * W, where K is the channel spacing, in mm, and W is the width of the cross-sectional rectangle of the medium channel, in mm.

[0021] Further, the diameters of the channel inlet and the channel outlet are equal.

[0022] Further, the diameters of the channel inlet and the channel outlet satisfy:

[0023] D = 6 * W * H / (W + H);

[0024] where, W is the width of the cross-sectional rectangle of the medium channel, in mm;

[0025] H is the height of the cross-sectional rectangle of the medium channel, in mm;

[0026] D is the diameter of the channel inlet and the channel outlet, in mm.

[0027] On the other hand, the present invention also provides a design method for a multi-branch parallel skin flow channel for designing the above multi-branch parallel skin flow channel, including the following steps:

[0028] S1: Obtain the actually available rectangular skin;

[0029] S2: Design the preliminary shape and size of the multi-branch parallel skin flow channel to obtain the size and shape of the target flow channel;

[0030] S3: According to the size and shape of the target flow channel, use the sketch tool of the modeling software to draw the basic shape and size of the flow channel, the first partition and the second partition on the plane;

[0031] S4: Use the feature tool of the modeling software to convert the sketch into a three-dimensional entity to obtain the first multi-branch parallel skin flow channel model;

[0032] S5: Use the modeling software to extract the inner cavity model of the first multi-branch parallel skin flow channel model, import it into the simulation software for mesh generation, boundary condition setting, working fluid physical property parameter setting and solution parameter setting, and perform a solution to obtain the flow resistance of the flow channel, the flow rate of the medium flow channel and the average temperature;

[0033] S6: Analyze the flow resistance of the flow channel, the flow rate of the medium flow channel and the average temperature obtained in step S5. According to the analysis results, optimize the structure of the first multi-branch parallel skin flow channel model, widen the distance between the long side wall of the two converging flow channels and the U-shaped wall of the first U-shaped partition and the distance between the long side wall of the two converging flow channels and the U-shaped wall of the second U-shaped partition to obtain the second multi-branch parallel skin flow channel model. Perform a simulation analysis on the flow resistance, flow rate and average temperature of the second multi-branch parallel skin flow channel model. According to the simulation analysis results of the second multi-branch parallel skin flow channel model and the first multi-branch parallel skin flow channel model, judge whether the simulation analysis structure meets the stop iteration condition. If it meets, determine the second multi-branch parallel skin flow channel model as the final skin flow channel model. If it does not meet, optimize the structure of the second multi-branch parallel skin flow channel model, repeat the simulation analysis until the Nth multi-branch parallel skin flow channel model obtained after N iterations meets the stop iteration condition, which is the final multi-branch parallel skin flow channel model.

[0034] Further, in step S5, the scale of the mesh is 0.01 times the diameter of the flow channel inlet.

[0035] Further, in step S6, the condition for stopping iteration is: the flow resistance of the (N - 1)th multi-branch parallel skin flow channel model is P N-1 , the flow resistance of the Nth multi-branch parallel skin flow channel model is P N , when it satisfies abs(P N - P N-1 ) / PN-1 When it is ≤ 0.01, stop the iteration, where abs is the absolute value.

[0036] Compared with the prior art, the present invention can achieve at least one of the following beneficial effects:

[0037] 1. The multi-branch parallel skin flow channel of the present invention passes through three "U"-shaped dielectric flow channels, which are nested and arranged side by side in sequence from the edge to the center along the width direction of the skin, and then are interconnected through the first collecting flow channel and the second collecting flow channel on the side of the mouth of the "U" shape. When the multi-branch parallel skin flow channel is applied to the aircraft skin heat exchanger, it can maintain the continuous operation of the electronic equipment for more than 2 hours with a relatively small occupation of the space inside the aircraft platform cabin.

[0038] 2. When the multi-branch parallel skin flow channel of the present invention is applied to a heating device with a heat flux density of 50 W / cm 2 in the aircraft platform, it has a relatively small flow resistance and a relatively large heat exchange area.

[0039] 3. When the multi-branch parallel skin flow channel of the present invention is applied to the aircraft skin heat exchanger, only the skin is appropriately thickened at the position of the flow channel, without occupying additional space inside the cabin.

[0040] 4. When the multi-branch parallel skin flow channel of the present invention is applied to the aircraft skin heat exchanger, the heat generated by the electronic equipment is transported to the skin through the circulation pipeline, and then the temperature is reduced through the heat exchange between the skin and the outside air, realizing the application requirements of the cold source equipment in the aircraft heat dissipation system with a small occupation of the aircraft platform space, a long continuous working time, a small flow resistance under a high heat flux density, and a large heat dissipation area; when the multi-branch parallel skin flow channel of the present invention is applied to the aircraft cold source equipment, the flow resistance of the flow channel ≤ 1500 Pa, and the heat exchange area ≥ 25000 mm 2 .

[0041] In the present invention, the above technical solutions can also be combined with each other to achieve more preferred combination schemes. Other features and advantages of the present invention will be described in the subsequent specification, and some advantages can be made obvious from the specification or understood by implementing the present invention. The objectives and other advantages of the present invention can be realized and obtained from the content specifically pointed out in the specification and the drawings. BRIEF DESCRIPTION OF THE DRAWINGS

[0042] The drawings are only for the purpose of showing specific embodiments and are not considered to be a limitation of the present invention. Throughout the drawings, the same reference signs represent the same components.

[0043] Figure 1 is a schematic diagram of the multi-branch parallel skin flow channel of the present invention;

[0044] Figure 2Combined pressure contour map of the multi-branch parallel skin flow channel of the present invention;

[0045] Figure 3 Structural diagram of the ground verification system in Embodiment 1 of the present invention.

[0046] Reference numerals: 1 - First medium flow channel; 2 - Second medium flow channel; 3 - Third medium flow channel; 4 - First collecting flow channel; 5 - Second collecting flow channel; 6 - First partition; 7 - Second partition; 8 - Flow channel inlet; 9 - Flow channel outlet; D - Diameter of the flow channel inlet; R - Fillet radius of the three medium flow channels; W1 - Distance between the long side walls of the two collecting flow channels and the U-shaped wall of the first partition; W2 - Distance between the long side walls of the two collecting flow channels and the U-shaped wall of the second partition; A - A - Section direction; W - Rectangular width of the flow channel cross-section in the A - A direction; H - Rectangular height of the flow channel cross-section in the A - A direction; R' - Fillet radius of the rectangular cross-section of the flow channel in the A - A direction; K - Flow channel spacing. Detailed implementation manners

[0047] The preferred embodiments of the present invention will be specifically described below in conjunction with the accompanying drawings, in which the accompanying drawings form a part of this application and are used together with the embodiments of the present invention to explain the principles of the present invention, and are not used to limit the scope of the present invention.

[0048] A multi-branch parallel skin flow channel is provided inside the skin and includes a flow channel inlet, a flow channel outlet, a first medium flow channel, a second medium flow channel, a third medium flow channel, a first collecting flow channel, and a second collecting flow channel;

[0049] The first medium flow channel, the second medium flow channel, and the third medium flow channel are all "U"-shaped flow channels, and the first collecting flow channel and the second collecting flow channel are trapezoid-like right-angle flow channels; the trapezoid-like right-angle flow channel is in the shape of a right trapezoid as a whole, and only the corners of the flow channel are rounded;

[0050] The first medium flow channel and the second medium flow channel are separated by a "U"-shaped first partition, and the second medium flow channel and the third medium flow channel are separated by a "U"-shaped second partition;

[0051] The first medium flow channel, the second medium flow channel, and the third medium flow channel are in parallel and converge at the flow channel inlet and the flow channel outlet to form the first collecting flow channel and the second collecting flow channel;

[0052] It is understandable that the first medium flow channel, the second medium flow channel, and the third medium flow channel are all "U"-shaped flow channels. Along the width direction of the skin, the first medium flow channel, the second medium flow channel, and the third medium flow channel are nested and arranged side by side in sequence from the edge to the center. The bottoms of the "U" shapes of the first medium flow channel, the second medium flow channel, and the third medium flow channel are located at one end of a short side of the skin, and the mouths of the "U" shapes of the first medium flow channel, the second medium flow channel, and the third medium flow channel are located at the other short side of the skin opposite to the bottom; one side of the "U" shape of the first medium flow channel, the second medium flow channel, and the third medium flow channel is symmetrically arranged with the other side of the "U" shape; the first medium flow channel, the second medium flow channel, and the third medium flow channel are in parallel connection and are interconnected through the first collecting flow channel and the second collecting flow channel on the side of the "U" mouth. One ends of the first medium flow channel, the second medium flow channel, and the third medium flow channel are collected and interconnected through the first collecting flow channel; the other ends of the first medium flow channel, the second medium flow channel, and the third medium flow channel are collected and interconnected through the second collecting flow channel.

[0053] It can be understood that the first medium flow channel and the second medium flow channel are separated by the first "U"-shaped partition board, and the second medium flow channel and the third medium flow channel are separated by the second "U"-shaped partition board. The first medium flow channel, the second medium flow channel, and the third medium flow channel are cavities opened in the skin, and the skin matrix between the cavities forms a partition structure between the flow channels.

[0054] The cross-section of the first medium flow channel, the second medium flow channel, and the third medium flow channel facing the "U" mouth direction is rectangular. The sides of the rectangle are transitioned by rounded corners. The width of the rectangle is W, the height is H, and the radius of the rounded corner is R'. The radius of the rounded corner R' satisfies:

[0055] R' = 1 / 2 * min(W, H);

[0056] When the radius of the rounded corner R' satisfies this condition, it can play a self-supporting role and no additional support is required during the subsequent additive manufacturing process. The unit is all mm.

[0057] The first medium flow channel, the second medium flow channel, and the third medium flow channel are equidistant from each other. The distance is K, with the unit of mm, and it satisfies:

[0058] 1 / 2 * W ≤ K ≤ 3 / 4 * W;

[0059] When the flow channel distance satisfies this condition, the heat dissipation effect of the skin can be improved, and the convective heat transfer amount and heat conduction amount of the skin can be balanced.

[0060] The flow channel inlet and the flow channel outlet are cylindrical and are respectively connected to the first collecting flow channel and the second collecting flow channel. The diameters are both D, and it satisfies:

[0061] D = 6 * W * H / (W + H), with the unit of mm;

[0062] The diameters of the runner inlet and the runner outlet satisfy this condition, which can ensure sufficient flow supply of the medium at the inlet and outlet of the runner.

[0063] The runner inlet and the runner outlet are respectively arranged at both ends of the short side on the right side of the skin. The distance between the runner inlet and the short side on the right side of the skin and the long side on the upper side of the skin is 3D. The distance between the runner outlet and the short side on the right side of the skin and the long side on the lower side of the skin is 3D. The positions of the runner inlet and the runner outlet satisfy this condition, which can ensure that the medium traverses the entire skin runner.

[0064] The fillet radius at the "U"-shaped bottom corner of the first medium runner, the second medium runner and the third medium runner is R, satisfying:

[0065] 1 / 2*W ≤ R ≤ 2 / 3*W, unit: mm;

[0066] The fillet radius R at the "U"-shaped bottom corner of the medium runner satisfies this condition, which can ensure the flow guiding effect of the runner.

[0067] The long sides of the first collecting runner and the second collecting runner are flush. The distance between the long side wall surfaces of the two collecting runners and the U-shaped opening wall surface of the first partition is W1. The distance between the long side wall surfaces of the two collecting runners and the U-shaped opening wall surface of the second partition is W2. W1 satisfies W1 = 3 / 2*W, W2 satisfies W2 = 3 / 2*W1. W1 and W2 satisfy the above conditions, which can evenly distribute the flow rates in the three medium runners and make the flow rate ratio in the three medium runners close to 1:1:1.

[0068] The present invention also provides a design method for a multi-branch parallel skin runner for manufacturing the above multi-branch parallel skin runner, including the following steps:

[0069] S1: Obtain an actually available rectangular skin;

[0070] S2: Design the preliminary shape and size of the multi-branch parallel skin runner to obtain the size and shape of the target runner;

[0071] S3: According to the size and shape of the target runner, use the sketch tool of the modeling software to draw the basic shape and size of the runner, the first U-shaped partition and the second U-shaped partition on the plane;

[0072] S4: Use the feature tool of the modeling software to convert the sketch into a three-dimensional entity to obtain the first multi-branch parallel skin runner model;

[0073] S5: Extract the inner cavity model of the first multi-branch parallel skin flow channel model using modeling software, import it into simulation software for mesh generation, boundary condition setting, working fluid property parameter setting, and solution parameter setting, and then solve to obtain the flow channel flow resistance, medium flow channel flow rate, and average temperature.

[0074] S6: Analyze the flow channel flow resistance, medium flow channel flow rate, and average temperature obtained in step S5. According to the analysis results, optimize the structure of the first multi-branch parallel skin flow channel model.

[0075] Widen the distance between the long side wall of the two converging flow channels and the U-shaped opening wall of the first U-shaped partition, as well as the distance between the long side wall of the two converging flow channels and the U-shaped opening wall of the second U-shaped partition. Optimize the flow channel inlet and outlet sizes to obtain the second multi-branch parallel skin flow channel model, and conduct simulation analysis on the flow channel flow resistance, flow channel flow rate, and average temperature of the second multi-branch parallel skin flow channel model.

[0076] According to the simulation analysis results of the second multi-branch parallel skin flow channel model and the first multi-branch parallel skin flow channel model, determine whether the simulation analysis structure meets the stop iteration condition. If it meets, determine the second multi-branch parallel skin flow channel model as the final skin flow channel model. If it does not meet, optimize the structure of the second multi-branch parallel skin flow channel model, repeat the simulation analysis until the Nth multi-branch parallel skin flow channel model obtained after N iterations meets the stop iteration condition, which is the final multi-branch parallel skin flow channel model.

[0077] Specifically, in step S2, design the preliminary shape and size of the multi-branch parallel skin flow channel to obtain the size and shape of the target flow channel, including the following steps:

[0078] S21: Set the flow channel inlet and outlet on the skin, and determine the positions and sizes of the flow channel inlet and outlet.

[0079] Specifically, the position of the flow channel inlet is 3D away from the right short side and the upper long side of the skin, and the position of the flow channel outlet is 3D away from the right short side and the lower side of the skin, where D is the diameter of the flow channel inlet and outlet.

[0080] S22: Set the first medium flow channel on the skin. This medium flow channel is a U-shaped flow channel, with a distance from the long side of the skin > 2 mm and a distance from the short side of the skin > 2 mm.

[0081] Among them, the cross-section of this medium flow channel facing the "U" opening direction is a rectangle, with a width of W, a height of H, and a fillet radius of R'. Its fillet radius R' satisfies: R' = 1 / 2 * min(W, H)

[0082] S23: Set a second medium flow channel on the skin. The shape and size of the second medium flow channel are the same as those of the first medium flow channel. The distance between the second medium flow channel and the first medium flow channel is K, satisfying 1 / 2*W ≤ K ≤ 3 / 4*W;

[0083] S24: Set a third medium flow channel on the skin. The shape and size of the third medium flow channel are the same as those of the second medium flow channel. The distance between the third medium flow channel and the second medium flow channel is K, satisfying 1 / 2*W ≤ K ≤ 3 / 4*W;

[0084] S25: The first medium flow channel, the second medium flow channel and the third medium flow channel are in parallel and converge at the flow channel inlet and the flow channel outlet to form a first converging flow channel and a second converging flow channel, obtaining the size and shape of the target flow channel.

[0085] Specifically, in step S5, use modeling software to extract the inner cavity model of the first multi-branch parallel skin flow channel model, import it into simulation software for mesh generation, and perform mesh independence analysis. The mesh scale is D / 100, which can balance simulation efficiency and accuracy;

[0086] Then set the boundary conditions. The boundary conditions are: set velocity and temperature boundary conditions at the flow channel inlet position, the velocity value is 3.5 - 4 L / min, and the temperature value is 50 - 60 °C; set pressure boundary conditions at the flow channel outlet position, the pressure value is 0 - 0.1 MPa; set thermal boundary conditions on the outer surface of the skin, the convective heat transfer coefficient is 300 - 400 W / (m 2 -K), and the ambient air temperature value is 10 - 20 °C.

[0087] Set the working fluid physical property parameters, including working fluid density, specific heat capacity, and viscosity;

[0088] The solution parameters are the number of calculation steps and the convergence residual. The number of calculation steps ≥ 500, and the convergence residual ≤ 1E-6; then perform simulation operation and solution to obtain the flow channel flow resistance, the flow rate and average temperature of the medium flow channel.

[0089] Specifically, in step S6, the condition for stopping iteration is: the flow resistance of the (N - 1)th multi-branch parallel skin flow channel model is P N-1 , and the flow resistance of the Nth multi-branch parallel skin flow channel model is P N , when abs(P N -P N-1 ) / P N-1 ≤ 0.01, stop iteration to obtain the final multi-branch parallel skin flow channel model.

[0090] Specifically, for the final multi-branch parallel skin flow channel model obtained in step S6, the long sides of the first converging channel and the second converging channel are flush. The distance between the long side walls of the two converging channels and the U-shaped wall of the first partition is W1, and the distance between the long side walls of the two converging channels and the U-shaped wall of the second partition is W2. W1 satisfies W1 = 3 / 2 * W, and W2 satisfies W2 = 3 / 2 * W1. The diameters D of the flow channel inlet and the flow channel outlet satisfy D = 6 * W * H / (W + H).

[0091] The multi-branch parallel skin flow channel of the present invention can be applied to the cold source equipment in the aircraft liquid cooling system. Using a part of the aircraft skin, the flow channel flows through the skin through the inlets and outlets on the inner side of the cabin, and exchanges heat with the outside through the skin, so as to achieve the refrigeration effect.

[0092] Embodiment 1

[0093] The multi-branch parallel skin flow channel of this embodiment is specifically a three-branch parallel skin flow channel, including a flow channel inlet, a flow channel outlet, a first medium flow channel, a second medium flow channel, a third medium flow channel, a first converging channel, and a second converging channel; as Figure 1 shown.

[0094] The first medium flow channel, the second medium flow channel, and the third medium flow channel are "U"-shaped flow channels, and the first converging channel and the second converging channel are trapezoid-like right-angle flow channels; as Figure 1 shown, the trapezoid-like right-angle flow channel is in the shape of a right trapezoid as a whole, and only the corners are rounded to form the flow channel corners;

[0095] The first medium flow channel and the second medium flow channel are separated by a "U"-shaped first partition, and the second medium flow channel and the third medium flow channel are separated by a "U"-shaped second partition;

[0096] The first medium flow channel, the second medium flow channel, and the third medium flow channel are connected in parallel and converge at the flow channel inlet and the flow channel outlet to form the first converging channel and the second converging channel;

[0097] The cross-sections of the first medium flow channel, the second medium flow channel, and the third medium flow channel facing the "U" port are rectangles. The width of the rectangle is W = 9 mm, the height is H = 3 mm, and the fillet radius is R' = 1.5 mm, satisfying: R' = 1 / 2 * min(W, H);

[0098] The first medium flow channel, the second medium flow channel, and the third medium flow channel are equidistant from each other, and the spacing is K = 6 mm, satisfying 1 / 2 * W ≤ K ≤ 3 / 4 * W;

[0099] The diameters of the flow channel inlet and the flow channel outlet are D = 13.5 mm, satisfying D = 6 * W * H / (W + H);

[0100] The fillet radius at the corners of the first medium flow channel, the second medium flow channel, and the third medium flow channel is R = 5 mm, satisfying 1 / 2*W ≤ R ≤ 2 / 3*W;

[0101] The long sides of the first converging flow channel and the second converging flow channel are flush. The distance between the long side walls of the two converging flow channels and the U-shaped wall of the first U-shaped partition is W1, and the distance between the long side walls of the two converging flow channels and the U-shaped wall of the second U-shaped partition is W2. W1 is 13.5 mm, satisfying W1 = 3 / 2*W, and W2 is 20.25 mm, satisfying W2 = 3 / 2*W1. Meeting the above conditions for W1 and W2 can evenly distribute the flow rates in the three medium flow channels, making the flow rate ratio in the three medium flow channels close to 1:1:1.

[0102] The combined pressure contour map of the three-branch parallel skin flow channel in this Embodiment 3 is as Figure 2 shown. It can be seen from the figure that the flow resistance obtained from the simulation calculation of the three-branch parallel skin flow channel in this embodiment is 1218.04 Pa.

[0103] Embodiment 2

[0104] The three-branch parallel skin flow channel designed in Embodiment 1 is actually verified by a ground verification system.

[0105] The structure of the ground verification system is as Figure 3 shown. The verification system consists of a liquid storage tank, a flow meter, a gear pump, a simulated heat load, a heat dissipation skin, and sensors. The sensors are set at the inlet and outlet positions of the S-shaped single-series skin flow channel;

[0106] The verification conditions are: a heat flux of 50 W / cm 2 is applied;

[0107] After actual verification by the ground verification system, the flow resistance of the multi-branch parallel skin flow channel is 1218.04 Pa, and the heat transfer area is 25163 mm 2 , showing good cooling and heat transfer effects.

[0108] Embodiment 3

[0109] This embodiment is a design method for the multi-branch parallel skin flow channel in Embodiment 1, including the following steps:

[0110] S1: Obtain the actually available skin;

[0111] S2: Design the preliminary shape and size of the multi-branch parallel skin flow channel to obtain the size and shape of the target flow channel;

[0112] S21: Set the positions and sizes of the flow channel inlet and outlet on the skin

[0113] Specifically, the distance from the inlet of the flow channel to the right short side and the upper long side of the skin is 40.5 mm, i.e., 3D, and the distance from the outlet of the flow channel to the right short side and the lower long side of the skin is 40.5 mm, where D is the diameter of the inlet and outlet of the flow channel, and D = 6*W*H / (W + H);

[0114] S22: Set a first medium flow channel on the skin. The medium flow channel is a U-shaped flow channel, with a distance of 2 mm from the long side of the skin and a distance of 2 mm from the short side of the skin;

[0115] Among them, the cross-section of the medium flow channel facing the "U" opening direction is a rectangle. The width of the rectangle is W = 9 mm, the height is H = 3 mm, and the fillet radius is R' = 1.5 mm. The fillet radius R' satisfies: R' = 1 / 2*min(W, H)

[0116] S23: Set a second medium flow channel on the skin. The shape and size of the second medium flow channel are the same as those of the first medium flow channel. The spacing between the second medium flow channel and the first medium flow channel is K = 6 mm, satisfying 1 / 2*W ≤ K ≤ 3 / 4*W;

[0117] S24: Set a third medium flow channel on the skin. The shape and size of the third medium flow channel are the same as those of the second medium flow channel. The spacing between the third medium flow channel and the second medium flow channel is K = 6 mm, satisfying 1 / 2*W ≤ K ≤ 3 / 4*W;

[0118] S25: The first medium flow channel, the second medium flow channel, and the third medium flow channel are in parallel and converge at the inlet and outlet of the flow channel to form a first converging flow channel and a second converging flow channel, obtaining the size and shape of the target flow channel;

[0119] S3: According to the size and shape of the target flow channel, use the sketch tool of the modeling software to draw the basic shape and size of the flow channel, the first U-shaped partition, and the second U-shaped partition on the plane;

[0120] S4: Use the feature tool of the modeling software to convert the sketch into a three-dimensional entity, obtaining the first multi-branch parallel skin flow channel model;

[0121] S5: Use the modeling software to extract the inner cavity model of the first multi-branch parallel skin flow channel model, import it into the simulation software for mesh generation, boundary condition setting, working fluid property parameter setting, and solution parameter setting, and perform the solution to obtain the flow resistance of the flow channel, the flow rate of the medium flow channel, and the average temperature;

[0122] Among them, the mesh scale is D / 100, which can balance the simulation efficiency and accuracy;

[0123] The boundary conditions are as follows: velocity and temperature boundary conditions are set at the inlet of the flow channel, with a velocity value of 3.5 L / min and a temperature value of 50 °C; a pressure boundary condition is set at the outlet of the flow channel, with a pressure value of 0.1 MPa; a thermal boundary condition is set on the outer surface of the skin, with a convective heat transfer coefficient of 300 W / (m 2 -K), and the ambient air temperature value is 10 °C;

[0124] Set the physical properties of the working medium: the medium is 65% ethylene glycol solution, with a density of 1069.145 kg / m 3 , a specific heat capacity of 3.165 kJ / kg*K, and a viscosity of 1.91 mPa*s.

[0125] The solution parameters are the number of calculation steps and the convergence residual. The number of calculation steps is 500 steps, and the convergence residual is 1E-6.

[0126] S6: Analyze the flow resistance, medium flow rate in the flow channel, and average temperature obtained in step S5. According to the analysis results, optimize the structure of the first multi-branch parallel skin flow channel model, widen the distance between the long side walls of the two converging flow channels and the U-shaped wall of the first U-shaped partition, and the distance between the long side walls of the two converging flow channels and the U-shaped wall of the second U-shaped partition, to obtain the second multi-branch parallel skin flow channel model, and conduct a simulation analysis on the flow resistance, flow rate, and average temperature of the second multi-branch parallel skin flow channel model.

[0127] Among them, the flow resistance of the second multi-branch parallel skin flow channel model is P 2 = 1218.04 Pa, and the flow resistance of the first multi-branch parallel skin flow channel model is P 1 = 1218.05 Pa, satisfying abs(P N -P N-1 ) / P N-1 ≤ 0.01, stop the iteration, and the second multi-branch parallel skin flow channel model is the final multi-branch parallel skin flow channel model.

[0128] Comparative Example 1

[0129] The multi-branch parallel skin flow channel of this comparative example includes a flow channel inlet, a flow channel outlet, a first medium flow channel, a second medium flow channel, a third medium flow channel, a first converging flow channel, and a second converging flow channel;

[0130] The first medium flow channel, the second medium flow channel, and the third medium flow channel are "U"-shaped flow channels, and the first converging flow channel and the second converging flow channel are trapezoidal flow channels;

[0131] The first medium flow channel and the second medium flow channel are separated by a "U"-shaped first partition, and the second medium flow channel and the third medium flow channel are separated by a "U"-shaped second partition;

[0132] The first medium flow channel, the second medium flow channel, and the third medium flow channel are in parallel and converge at the flow channel inlet and the flow channel outlet to form a first converging flow channel and a second converging flow channel;

[0133] The cross-sections of the first medium flow channel, the second medium flow channel, and the third medium flow channel facing the "U" port are rectangular, with the width of the rectangle being W = 9 mm, the height being H = 3 mm, and the fillet radius being R' = 1.5 mm, satisfying: R' = 1 / 2 * min(W, H);

[0134] The first medium flow channel, the second medium flow channel, and the third medium flow channel are equidistant from each other, with the spacing being K = 4 mm, not satisfying 1 / 2 * W ≤ K ≤ 3 / 4 * W;

[0135] The diameters of the flow channel inlet and the flow channel outlet are D = 13.5 mm, satisfying D = 6 * W * H / (W + H);

[0136] The fillet radii at the corners of the first medium flow channel, the second medium flow channel, and the third medium flow channel are R = 5 mm, satisfying 1 / 2 * W ≤ R ≤ 2 / 3 * W;

[0137] The long sides of the first converging flow channel and the second converging flow channel are flush. The distance between the long side walls of the two converging flow channels and the U-port wall of the first U-shaped partition is W1, and the distance between the long side walls of the two converging flow channels and the U-port wall of the second U-shaped partition is W2. W1 is 13.5 mm, satisfying W1 = 3 / 2 * W, and W2 is 13.5 mm, not satisfying W2 = 3 / 2 * W1.

[0138] Apply the multi-branch skin flow channels of Example 1 and Comparative Example 1 to the cold source equipment in the aircraft liquid cooling system, using a part of the aircraft skin. After actual verification by the ground verification system, the flow resistance of the multi-branch parallel skin flow channel of Example 1 is 1218.04 Pa, and the heat exchange area is 25163 mm 2 , the flow resistance of the multi-branch parallel skin flow channel of Comparative Example 1 is 1518.26 Pa, and the heat exchange area is 23102 mm 2 , and the multi-branch skin flow channel of Example 1 applied to the cold source equipment in the aircraft liquid cooling system is superior to Comparative Example 1.

[0139] The above is only a preferred specific embodiment of the present invention, but the protection scope of the present invention is not limited thereto. Any changes or substitutions that can be easily thought of by those skilled in the art within the technical scope disclosed by the present invention should be covered within the protection scope of the present invention.

Claims

1. A multi-branch parallel skin flow channel is arranged inside the skin. Characterized in that, it includes a flow channel inlet, a flow channel outlet, a first medium flow channel, a second medium flow channel, a third medium flow channel, a first collecting flow channel and a second collecting flow channel; The first medium flow channel, the second medium flow channel and the third medium flow channel are "U"-shaped flow channels; Along the width direction of the skin, the first medium flow channel, the second medium flow channel and the third medium flow channel are nested and arranged side by side in sequence from the edge to the center; The first collecting flow channel and the second collecting flow channel are symmetrically arranged on both sides of the open end of the "U"; One ends of the first medium flow channel, the second medium flow channel and the third medium flow channel are collected through the first collecting flow channel and are interconnected; the other ends of the first medium flow channel, the second medium flow channel and the third medium flow channel are collected through the second collecting flow channel and are interconnected; The flow channel inlet is located on the side of the first collecting flow channel and is connected to the first collecting flow channel; the flow channel outlet is located on the side of the second collecting flow channel and is connected to the second collecting flow channel.

2. The multi-branch parallel skin flow channel according to claim 1, Characterized in that, The cross-sections of the first medium flow channel, the second medium flow channel and the third medium flow channel facing the "U" opening direction are rectangular, and the sides of the rectangle are transitioned by rounded corners.

3. The branch parallel skin flow channel according to claim 2, Characterized in that, The radius of the rounded corner of the rectangle satisfies: R’ = 1 / 2 * min(W, H); Wherein, W is the width of the cross-sectional rectangle of the medium flow channel, in mm; H is the height of the cross-sectional rectangle of the medium flow channel, in mm; R’ is the radius of the rounded corner of the cross-sectional rectangle of the medium flow channel, in mm.

4. The multi-branch parallel skin flow channel according to claim 2, Characterized in that, The distances between the first medium flow channel, the second medium flow channel and the third medium flow channel are equal.

5. The multi-branch parallel skin flow channel according to claim 4, Characterized in that, The distance between the first medium flow channel, the second medium flow channel and the third medium flow channel satisfies 1 / 2 * W ≤ K ≤ 3 / 4 * W, where K is the flow channel spacing, in mm, and W is the width of the cross-sectional rectangle of the medium flow channel, in mm.

6. The multi-branch parallel skin flow channel according to claim 2, Characterized in that, The diameters of the flow channel inlet and the flow channel outlet are equal.

7. The multi-branch parallel skin flow channel according to claim 6, Characterized in that, The diameters of the flow channel inlet and the flow channel outlet satisfy: D = 6 * W * H / (W + H); Wherein, W is the width of the cross-sectional rectangle of the medium flow channel, in mm; H is the height of the cross-sectional rectangle of the medium flow channel, in mm; D is the diameter of the flow channel inlet and the flow channel outlet, in mm.

8. A design method for a multi-branch parallel skin flow channel, used for designing the multi-branch parallel skin flow channel according to any one of claims 1-7, including the following steps: S1: Obtain an actually available rectangular skin; S2: Design the preliminary shape and size of the multi-branch parallel skin flow channel to obtain the size and shape of the target flow channel; S3: According to the size and shape of the target flow channel, use the sketch tool of the modeling software to draw the basic shape and size of the flow channel, the first partition board and the second partition board on the plane. S4: Use the feature tool of the modeling software to convert the sketch into a 3D solid, obtaining the first multi-branch parallel skin flow channel model; S5: Use the modeling software to extract the inner cavity model of the first multi-branch parallel skin flow channel model, import it into the simulation software for mesh generation, boundary condition setting, working fluid property parameter setting, and solution parameter setting, and perform a solution to obtain the flow channel flow resistance, medium flow channel flow rate, and average temperature; S6: Analyze the flow channel flow resistance, medium flow channel flow rate, and average temperature obtained in step S5; According to the analysis results, optimize the structure of the first multi-branch parallel skin flow channel model, widen the distance between the long side walls of the two converging flow channels and the U-port walls of the first U-shaped partition, and the distance between the long side walls of the two converging flow channels and the U-port walls of the second U-shaped partition, obtaining the second multi-branch parallel skin flow channel model. Perform a simulation analysis on the flow channel flow resistance, flow channel flow rate, and average temperature of the second multi-branch parallel skin flow channel model. According to the simulation analysis results of the second multi-branch parallel skin flow channel model and the first multi-branch parallel skin flow channel model, determine whether the simulation analysis structure meets the stop iteration condition. If it meets, determine the second multi-branch parallel skin flow channel model as the final skin flow channel model. If it does not meet, optimize the structure of the second multi-branch parallel skin flow channel model; Repeat the simulation analysis until the Nth multi-branch parallel skin flow channel model obtained after N iterations meets the stop iteration condition, which is the final multi-branch parallel skin flow channel model.

9. According to the design method described in claim 8, characterized in that, in step S5, the scale of the mesh is 0.01 times the diameter of the flow channel inlet.

10. According to the design method described in claim 8, characterized in that, In step S6, the condition for stopping iteration is that the flow resistance of the (N - 1)-th multi-branch parallel skin flow channel model is P N-1 , and the flow resistance of the N-th multi-branch parallel skin flow channel model is P N . When it satisfies abs(P N - P N-1 ) / P N-1 ≤ 0.01, stop the iteration, where abs is the absolute value.

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