TPMS radiator and design method thereof

Abstract

This invention provides a TPMS heat sink and its design method, comprising: Step 1: Based on the target heat transfer performance and spatial constraints, selecting the TPMS topology as the internal flow channel structure of the heat transfer core, and adjusting the unit cell parameters to generate a heat transfer core model; Step 2: Designing an encapsulation shell around the heat transfer core model, and performing structural strength simulation verification; Step 3: Manufacturing an integrated heat sink using additive manufacturing technology, and optimizing the laser process parameter set for the TPMS structure overhang surface through experimental design methods to suppress slag buildup on the overhang surface; Step 4: Treating the surface of the TPMS internal flow channel using a multiphase jet polishing process; Step 5: Verifying the heat transfer performance and structural reliability of the heat sink through multi-condition heat transfer experiments and overpressure experiments. This invention solves the technical problem of the lack of a systematic integrated method for the entire process of engineering application of TPMS heat sinks, from structural design, additive manufacturing process optimization, internal flow channel post-processing to performance verification.

Description

Technical Field

[0001] This invention relates to the technical field of radiators, and more particularly to a TPMS radiator and its design method. Background Technology

[0002] High-power-density equipment such as aero engines places increasingly stringent performance requirements on fuel and lubricating oil coolers, demanding efficient heat dissipation and low flow resistance within a compact space. For example... Figure 1 As shown, traditional shell-and-tube, column-type, wing-type, and flat-plate heat sinks are limited by manufacturing processes and have simple flow channel structures, making it difficult to balance efficiency, resistance, and space adaptability. Additive manufacturing (AM) technology has made it possible to manufacture complex internal flow channel structures, among which TPMS structures are considered an ideal choice due to their high specific surface area and continuous smooth flow channels.

[0003] However, successfully applying TPMS structures to actual heat sink products faces a series of challenges: First, there is a lack of mature methods for systematically matching TPMS structural parameters with target heat dissipation performance, flow resistance, and spatial constraints; second, during additive manufacturing of TPMS structures, slag buildup defects easily occur on the overhanging surfaces, severely affecting the surface quality and heat dissipation performance of the flow channels; third, post-processing and ensuring cleanliness of complex closed internal flow channels are difficult; fourth, a complete closed-loop process from design and manufacturing to verification is needed to ensure the performance and reliability of the final product. Existing technologies mostly focus on the theoretical advantages of TPMS structures or single process steps, lacking integrated solutions to the aforementioned engineering challenges.

[0004] Therefore, there is an urgent need in this field to develop a systematic and engineerable TPMS heatsink design method to solve the challenges of the entire process from structural design, process implementation, post-processing to performance verification. Summary of the Invention

[0005] The purpose of this invention is to provide a TPMS heat sink design method, which solves the technical problem that the existing technology lacks a systematic and integrated engineering application method that can solve the entire process of TPMS heat sink from structural design, additive manufacturing process optimization, internal flow channel post-processing to performance verification.

[0006] To solve the above-mentioned technical problems, the technical solution of the present invention is as follows: This invention provides a TPMS heat sink design method, comprising the following steps: Step 1: Topology and parametric design of heat exchange core: Based on the target heat transfer performance and spatial constraints, the three-period minimum surface (TPMS) topology is selected as the basic structure of the internal flow channel of the heat exchange core. By adjusting the unit cell size and surface wall thickness parameters, a heat exchange core model with a specific heat transfer area is generated. Step 2: Shell design and structural simulation: Design an encapsulation shell around the heat exchange core model to form an integrated 3D model of the heat sink, and perform structural strength simulation verification on the shell of the model; Step 3: Additive manufacturing and process optimization: The integrated heat sink is manufactured using additive manufacturing technology. Specifically, for the manufacturing of the TPMS structure overhang surface, the laser process parameters for contour scanning and path scanning are optimized using experimental design methods to suppress the drooping phenomenon on the overhang surface. Step 4: Post-treatment of inner flow channels: The surface of the TPMS inner flow channels of the formed heat sink is treated with multiphase jet polishing process to achieve the predetermined cleanliness level. Step 5: Performance Verification: Through multi-condition heat exchange experiments and overpressure experiments, verify the heat exchange performance and structural reliability of the radiator to ensure that it meets the usage requirements.

[0007] Furthermore, in step 1, the TPMS topology is a Gyroid structure.

[0008] Furthermore, in step 1, the curved wall thickness of the heat exchange core increases with the increase of the unit cell size.

[0009] Furthermore, in step 1, the unit cell size is parametrically adjusted to be in the range of 5-7 mm, and the curved surface wall thickness is in the range of 0.76-0.98 mm.

[0010] Furthermore, in step 3, the additive manufacturing technology specifically employs metal laser powder bed melting (SLM) technology to integrally form a heat exchange core containing complex TPMS flow channels based on model data.

[0011] Furthermore, in step 3, when scanning the overhanging surface, the parameters of the contour scan are set to a first energy density, which is used to form a dense and continuous initial solidification layer on the overhanging surface. The parameters of the path scan are set to a second energy density, which is lower than the first energy density, and are used to remelt and smooth the initial solidification layer, thereby synergistically suppressing the formation of slag.

[0012] The present invention also provides a TPMS heat sink, manufactured using any of the above-described design methods, comprising: The heat exchange core is integrally formed, and its internal flow channels are periodically arranged by the selected TPMS topology. The outer shell encapsulates the heat exchange core and has a fluid interface communicating with the inner flow channel and the inner cavity of the outer shell. The surface of the inner flow channel is a smooth surface that has undergone multiphase jet polishing treatment.

[0013] Compared with the prior art, the present invention has at least the following beneficial effects: (1) This invention organically integrates five key steps: parametric design of the heat exchange core, simulation of the shell structure, process optimization for the additive manufacturing overhang surface, post-processing of the internal flow channel, and multi-condition performance verification, forming a complete and closed-loop design and manufacturing process. This method overcomes the limitations of existing technologies that focus on a single link, ensuring controllability and coordination throughout the entire process from performance target setting to final product delivery, and realizing the engineering leap of TPMS radiators from "designable" to "manufacturable, verifiable, and applicable".

[0014] (2) This invention proposes specific and effective solutions to the core pain points in the engineering of TPMS heat sinks. Parametric performance is controlled by adjusting the unit cell size (e.g., 5-7 mm) and wall thickness (e.g., 0.76-0.98 mm); DOE-based laser process parameter optimization (e.g., a combination of contour scanning 240W / 600mm / s and path scanning 285W / 1150mm / s) effectively suppresses slag buildup on the overhanging surface; and multiphase jet polishing technology ensures the cleanliness of the internal flow channels meets the GJB-420B-2015 Level 3 standard. These specific technical measures work synergistically to guarantee the forming quality and service reliability of complex internal flow channels from the source and during the process.

[0015] (3) The TPMS radiator designed and manufactured using the method of this invention has been experimentally verified to meet the stringent requirements of high-end equipment in terms of comprehensive performance. In terms of structural strength, the maximum stress of the outer shell under an internal pressure of 1.5 MPa is 208.56 MPa, with a safety factor >1.2 (based on the yield strength of AlSi10Mg material of 253 MPa). Regarding heat exchange performance, under typical operating conditions (e.g., lubricating oil 105℃ / 30L / min, fuel oil 45℃ / 30L / min), the unit heat dissipation steadily increases with increasing fuel flow rate (e.g., 0.305 kW / ℃ for a 5mm unit cell at maximum fuel flow rate), and it passed the overpressure test at 1.5 MPa without permanent deformation or leakage. This proves that this method can successfully produce TPMS radiator products that combine high-efficiency heat exchange with high reliability. Attached Figure Description

[0016] To more clearly illustrate the specific embodiments of the present invention or the technical solutions in the prior art, the drawings used in the description of the specific embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are some embodiments of the present invention. For those skilled in the art, other drawings can be obtained from these drawings without creative effort.

[0017] Figure 1 Here are schematic diagrams of four traditional radiators: (a) shell-and-tube radiator, (b) column radiator, (c) finned radiator, and (d) flat plate radiator. Figure 2 Schematic diagrams of different types of TPMS structures: (a) TPMS Gyroid structure; (b) TPMS Schwarz P structure; Figure 3 The diagram shows the TPMS heat exchanger core model created using nTopology software. Figure 4 A 3D model of the encapsulation shell based on the heat exchange core design; Figure 5 The simulation cloud diagram shows the equivalent stress of the heat sink casing under an internal pressure of 1.5 MPa. Figure 6 The equivalent strain simulation cloud diagram of the heat sink casing under an internal pressure of 1.5 MPa; Figure 7 The simulation cloud diagram shows the total deformation of the radiator casing under an internal pressure of 1.5 MPa. Figure 8 Schematic diagrams of the overall radiator model and its fluid domain model: (a) radiator shell; (b) heat exchange core; (c) fluid domain model; Figure 9 Schematic diagram of additive manufacturing equipment and part printing layout: (a) BLT-S450 equipment; (b) Part printing layout diagram; Figure 10 Comparison images of slag adhesion on the lower surface of TPMS structures printed using different process parameters; Figure 11 Comparison of slag morphology on the lower surface of TPMS structure under different process parameters; Figure 12 Comparison of surface slag morphology under different process parameters in TPMS structures; Figure 13 A schematic diagram of the solid contamination classification standards for aviation working fluids; Figure 14 This is a topographic image of the internal flow channel surface of an unpolished radiator. Figure 15 This is a diagram showing the surface morphology of the internal flow channels of the radiator after jet polishing. Figure 16 The dynamic curve of heat dissipation per unit volume as a function of fuel flow rate under 5mm unit cell conditions; Figure 17 The kinetic curve of heat dissipation per unit volume as a function of fuel flow rate under a 5.5 mm unit cell condition; Figure 18 The dynamic curve of heat dissipation per unit volume as a function of fuel flow rate under 7mm unit cell operating conditions; Figure 19 The dynamic curve of heat dissipation per unit volume as a function of fuel flow rate under 5mm unit cell conditions; Figure 20The kinetic curve of heat dissipation per unit volume as a function of fuel flow rate under a 5.5 mm unit cell condition is shown. Figure 21 The kinetic curve of heat dissipation per unit volume as a function of fuel flow rate under 7mm unit cell conditions. Detailed Implementation

[0018] To make the objectives, technical solutions, and advantages of the embodiments of the present invention clearer, the technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0019] This embodiment provides a TPMS heat sink and its design method. The core process of this method includes five key steps, forming a complete chain from theoretical design to product verification, specifically including: Step 1: Heat exchange core topology and parametric design. Based on the target heat dissipation power and space constraints, a TPMS topology (such as Gyroid) is selected as the flow channel basis. By adjusting the unit cell size and wall thickness, a core model with a specific heat exchange area is generated (see Table 1), thus realizing the active design and control of performance.

[0020] Step 2: Shell design and structural simulation. The shell is used to cover the aforementioned core design to form a complete product model. The structural strength is checked by finite element analysis under preset working conditions (such as 1.5 MPa internal pressure) to ensure that the design meets the reliability requirements (see the strength simulation section).

[0021] Step 3: Additive manufacturing and process optimization. The heat sink is manufactured in an integrated manner using metal laser powder bed melting technology. In particular, for the manufacturing difficulty of TPMS overhang surface, the laser process parameters of contour scanning and path scanning are optimized by design of experiments (DOE) method (see Table 2-3) to suppress "slag" from the source and ensure the forming quality of complex internal flow channels.

[0022] Step 4: Post-treatment of the inner flow channel. The inner flow channel surface of the formed part is treated with multiphase jet polishing process to achieve the predetermined high cleanliness level (such as GJB-420B-2015 Level 3), eliminating the potential threat of residual particles to the system reliability.

[0023] Step 5: Performance verification. Through multi-condition heat exchange experiments covering the actual working range and overpressure experiments, data such as temperature and pressure are collected to comprehensively verify the heat exchange performance and structural integrity of the radiator (see the overpressure test table).

[0024] The above technical solution, through the sequential implementation of parametric design of the heat exchange core (adjusting TPMS unit cell and wall thickness based on target performance), shell strength simulation (such as 1.5MPa internal pressure verification), DOE process optimization for additive manufacturing overhangs (suppressing slag buildup), multiphase jet polishing post-treatment (achieving level 3 cleanliness), and multi-condition and overpressure experimental verification, forms a complete and engineering-implementable design method from performance design and manufacturing quality assurance to final verification. It successfully solves the systemic problem of transforming high-performance TPMS topology from theoretical models to actual products, and ensures that the final radiator meets the stringent requirements of high-end equipment in terms of efficiency, compactness, and reliability.

[0025] Specifically, the TPMS heat sink and its design method are implemented through the following core technical solutions, which include: 1. TPMS lubricating oil heat sink design; 2. Additive manufacturing and post-processing; 3. Operating condition verification experiments; 4. Conclusions; as follows: I. TPMS Lubricating Oil Radiator Design A minimal surface is a mathematical surface whose mean curvature is zero everywhere. Its periodic extension in three-dimensional space constitutes a triple-periodic minimal surface (TPMS). Based on the different implicit function expressions, TPMS can be divided into Gyroids (…). Figure 2 a, Formula 1.1), Schwarz P ( Figure 2 b, Formula 1.2) and other types.

[0026] (1.1) (1.2) Where x, y, and z represent spatial coordinates; ω = 2π / l, where l represents the length of the unit cell; and c is the aperture size within the TPMS unit. TPMS structures possess extremely high specific surface area, continuous smoothness, and self-supporting topological properties, making them ideal multifunctional lightweight structures and efficient heat exchange units. In various studies, Gyroid structures have exhibited optimal heat transfer performance and have therefore attracted considerable attention; however, their complex geometry makes them difficult to manufacture using traditional subtractive or forming processes. Additive manufacturing technology, particularly laser powder bed melting (SLM), provides the only feasible path to achieve such optimal topological structures. SLM technology can integrally form radiator cores containing complex TPMS flow channels, completely avoiding problems such as leakage, weight gain, and contact thermal resistance that may arise from traditional brazing processes, achieving integrated structure-function manufacturing.

[0027] Due to the adoption of integrated additive manufacturing technology, the design of this heat sink mainly consists of two parts: the heat exchange core and the outer shell. Three heat sinks with different unit cell sizes were designed, and their main parameters are shown in Table 1. Table 1 Main parameters of the three sets of radiators

[0028] The heat exchanger core is modeled using nTopology, and the model is as follows: Figure 3 As shown For the remaining outer casing of the radiator, this solution uses UG software to design a 5mm thick outer casing based on the aforementioned heat exchange core model. The final outer casing model is shown below. Figure 4 As shown. To verify its structural strength under actual working conditions, the outer shell was simulated and verified. The internal cavity pressure was set to 1.5 MPa (instantaneous working condition; under normal working conditions, pressure relief begins immediately after reaching 1.5 MPa). The simulation results are as follows. Figures 5 to 7 As shown in the figure. The results show that the maximum equivalent stress of the casing is 208.56 MPa. Considering that the yield strength of the additively manufactured AlSi10Mg material is 253 MPa, the calculated strength safety factor k of the radiator casing is greater than 1.2, which meets the requirements of the operating conditions.

[0029] Therefore, based on the above explanation, this solution uses UG and nTopology to design a heat sink model and its fluid domain model, as shown in the figure below. Figure 8 As shown.

[0030] II. Additive Manufacturing and Post-processing 2.1 Manufacturing Process Equipment and Materials: The BLT-S450 class large-scale L-PBF equipment is used, whose 450×450×600mm forming chamber allows for the printing of 4–6 units at a time (e.g., Figure 9 As shown: (a) BLT-S450 equipment; (b) part printing layout diagram) Radiator parts, significantly improving the efficiency and economy of mass production. The equipment precision ensures the feasibility of thin-walled features. The solution uses AlSi10Mg aluminum alloy as the base material, which is the optimal solution based on multiple considerations: Thermal conductivity: Its thermal conductivity is 110–150 W / (m·K), which is excellent among commonly used additive manufacturing metal materials and can meet the requirements of efficient heat transfer. AlSi10Mg is one of the most mature and widely used aluminum alloys in L-PBF process. Its melting and solidification characteristics and laser parameter window are clear, making it easy to obtain high-density formed parts. At the same time, AlSi10Mg has a relatively low coefficient of thermal expansion, which can reduce the stress caused by thermal cycling when combined with other metal parts, and improve the structural reliability and sealing integrity of the entire thermal management system under drastic temperature changes.

[0031] 2.2 Systematic Parameter Optimization Based on Design of Experiments (DOE) During the fabrication of the lower surface (i.e., the overhanging surface) of the TPMS structure, the lack of direct support causes the molten pool to easily collapse and spheroidize under gravity. Furthermore, the adhesion of incompletely melted powder or the condensation of spatter caused by overmelting leads to a "slag" phenomenon. This problem severely affects the surface quality and cleanliness of the flow channels within the radiator, disrupting the expected laminar or turbulent flow state and significantly reducing heat exchange efficiency. More seriously, during long-term operation, the detached slag may migrate with the cooling medium, clogging narrow flow channels or damaging precision pumps and valves, posing a serious threat to the reliability of the entire thermal management system. Therefore, we propose a systematic parameter optimization scheme based on DOE (Design of Engineering).

[0032] This study employs either a full factorial design or a partial factorial design (depending on the design matrix of the 72 experiments), setting an engineering-significant level range for each factor: Lower surface profile scan factor: Laser power: 20W-240W (wide range exploration, aiming to find the minimum effective power and the optimal power that can fully melt the powder) Scanning speed: 400 mm / s-800 mm / s (aimed at adjusting energy input density and action time).

[0033] Lower surface path scan factor: Laser power: 245W-345W (adjustable within the range of equipment safety and to avoid excessive spatter) Scanning speed: 1150 mm / s-1450 mm / s (aimed at reducing energy density and controlling melt depth and melt pool stability).

[0034] Theoretically, a 2-level, 4-factor full factorial design requires 16 sets of experiments. The 72 sets of experiments described in this report are based on the aforementioned 2-level design, further adding centroids to test curvature, or extending some important factors (such as power) to multiple levels, or including additional factors such as different scanning strategies (such as the number of contour scans), thus forming a more detailed and comprehensive experimental matrix. All experiments were conducted under the same equipment, atmosphere, and powder bed conditions to ensure comparability of results.

[0035] After wire cutting the feature structure, the slag on the lower surface and the condition of the lower side were observed using a digital microscope. (See the image below.) Figure 10 As shown, the three optimal process parameters (sample numbers 24, 40, and 77, process parameters as shown in Table 2) were selected and compared with the morphology of the lower side and lower surface of the TPMS Gyroid structure printed using the Part process. It can be observed that the lower side of samples 24 and 77 is smoother and free of slag, which reduces the area of ​​slag on the lower surface (e.g., Figure 11 As shown), compared to the previous example, the surface quality of the lower side of 24 is the best, and the parameters for its lower surface contour scan can be selected; at the same time, it was observed that 40 (as shown) Figure 12The slag on the lower surface of the (as shown) is finer and of better quality, and its lower surface path planning parameters can be selected.

[0036] Table 2. Several sets of better lower surface process parameters

[0037] The optimal parameter combination obtained after further verification is shown in Table 3: Table 3 Optimal Parameter Combinations

[0038] Contour scanning parameters: A laser power of 240W and a scanning speed of 600mm / s were used, optimizing the energy density to 133.33 J / mm². This ensures that, under suspended conditions, the laser has sufficient energy to penetrate and completely melt the powder, forming a dense, continuous initial solidified layer, providing a good "substrate" for subsequent path scanning.

[0039] Path scanning parameters: A laser power of 285W and a scanning speed of 1150mm / s were used, with the energy density controlled at 82.61 J / mm². This energy level is sufficient to moderately remelt and smooth the dense contour layer below, achieving good metallurgical bonding. At the same time, the size and dynamic state of the molten pool are effectively controlled, avoiding molten pool instability, material dripping, and increased splashing caused by excessive energy, thereby suppressing slag formation at the source.

[0040] 2.3 Post-processing This solution uses multiphase jet polishing (hereinafter referred to as jet polishing) process to polish the internal flow channel. The principle of jet polishing technology is to use ultrasonic vibration as an auxiliary means to spray droplets containing abrasive at high speed. High pressure gas is used to accelerate the abrasive instantaneously between narrow structures, so that the abrasive is injected at a very small angle and high speed when it impacts the surface of the structure, thereby effectively removing surface defects.

[0041] After polishing, a cleanliness test was conducted. The test method involved rinsing with a 0.3 MPa ethanol solution for 5 minutes, followed by filtering out loose particles using a 5 μm filter. The cleanliness test results for untreated radiators and radiators treated with jet polishing are shown in Tables 4 and 5. According to GJB-420B-2015 Classification of Solid Contamination in Aviation Working Fluids, such as... Figure 13 As shown, jet polishing can achieve a cleanliness level of 3.

[0042] Table 4. Cleanliness results of untreated radiators

[0043] Table 5. Cleanliness results of radiator treated with jet polishing process

[0044] After the cleanliness test, the heatsink was cut along the plane of symmetry using wire cutting to observe the morphology of the upper and lower surfaces of the polished TPMS and to perform roughness testing. The morphology of the upper and lower surfaces was characterized using a digital microscope. Figure 14-15 The surface morphology of the internal flow channels of the untreated radiator and the radiator treated by jet polishing are respectively measured by white light interferometer.

[0045] III. Operating Condition Verification Experiment 3.1 Preparations before the experiment 1. Check the experimental equipment: Check the installation of equipment such as fuel and oil coolers, flow meters, temperature sensors, and pressure sensors to ensure they are working properly.

[0046] Ensure accurate zero-point calibration of the flow meter and sensor to avoid affecting experimental data.

[0047] Check the levels and properties of fuel oil and lubricating oil to ensure they meet experimental requirements.

[0048] 2. System Initialization: Set the initial flow rates for fuel and lubricating oil to ensure that both fluids flow evenly within the radiator.

[0049] Start the system, warm it up, and run it for a period of time to ensure system stability.

[0050] 3.2 Experimental Procedure 1. Set initial conditions: Set the initial fuel flow rate (10 L / min), start the radiator, and record the parameters under the initial conditions (including fuel outlet temperature, fuel outlet pressure, etc.).

[0051] 2. Data Collection: The following data were recorded using temperature sensors, pressure sensors, and flow meters: Lubricating oil inlet temperature, lubricating oil outlet temperature, lubricating oil inlet pressure, lubricating oil outlet pressure, fuel oil inlet temperature, fuel oil outlet temperature, fuel oil inlet pressure, fuel oil outlet pressure.

[0052] 3. Gradually adjust the fuel flow rate: While keeping the lubricating oil flow rate constant, gradually adjust the fuel flow rate (15L / min, 17.5L / min, 20L / min, 22.5L / min, 25L / min, 27.5L / min, 30L / min), and after each adjustment, wait for the system to stabilize and record the parameters under stable conditions. Ensure that the data after each adjustment is stable for 1 to 3 minutes to obtain accurate experimental data.

[0053] 4. Repeat the experiment: To ensure the reliability of the experimental results, the experiment was repeated at least three times for each fuel flow setting, and the corresponding parameters were recorded.

[0054] 5. Overpressure test verification: After the operating condition verification is completed, increase the flow rate to bring the radiator to a pressure of 1.5MPa and maintain it for 5~10 seconds to observe whether permanent deformation occurs, whether oil leakage or seepage occurs, or whether cracks appear.

[0055] 3.3 Experimental Data and Results (1) Test under working condition 1 for fuel-oil radiator, i.e., lubricating oil inlet temperature 105℃, flow rate 30L / min; fuel inlet temperature 45℃, flow rate 30L / min, lubricating oil inlet temperature, outlet temperature, inlet pressure, outlet pressure, fuel inlet temperature, outlet temperature, inlet pressure, outlet pressure.

[0056] ①5mm unit cell: Operating condition 1: Lubricating oil inlet temperature 105℃; flow rate 30L / min; fuel oil inlet temperature 45℃

[0057] (1) (2) (3) (4) In equations (1) and (2) C 滑 =1.76+0.0029t(kJ / kg*℃), ρ 滑 =0.9849-0.000733t (g / cm³) 3 ); C 燃 =1.74+0.00963t(kJ / kg*℃), ρ 燃 = 0.8028-0.0007596t (g / cm³) 3 ) G 燃 Actual fuel flow rate G 滑 The measured flow rate of the lubricating oil is shown. It can be seen that the specific heat capacity and density of the lubricating oil change with temperature. Therefore, in the calculation process, we select the average inlet and outlet temperatures to represent the temperature of the lubricating oil. The calculation results for overall operating condition 1 are shown in the table below.

[0058] Calculation results for 5mm unit cell condition 1

[0059] With fuel mass flow rate G'fuel as x and unit heat dissipation as y, plot the kinetic curve for condition 1 in a 5mm unit cell, as shown below. Figure 16 As shown.

[0060] ②5.5mm unit cell: Operating condition 1: Lubricating oil inlet temperature 105℃; flow rate 30L / min; fuel oil inlet temperature 45℃

[0061] The calculation formulas can still be the previously mentioned formulas (1) to (4). Calculation results for 5.5mm unit cell condition 1

[0062] The kinetic curve for condition 1 of a 5.5mm unit cell is shown below. Figure 17 As shown.

[0063] ③7mm unit cell: Operating condition 1: Lubricating oil inlet temperature 105℃; flow rate 30L / min; fuel oil inlet temperature 45℃

[0064] The calculation formulas can still be the previously mentioned formulas (1) to (4). Calculation results for 7mm unit cell condition 1

[0065] The kinetic curve for condition 1 of 7mm unit cell is shown below. Figure 18 As shown.

[0066] (2) Test under working condition 2 for fuel-oil radiator technical requirements, i.e., lubricating oil inlet temperature 105℃, flow rate 15L / min; fuel inlet temperature 45℃, flow rate 30L / min, and collect lubricating oil inlet temperature, outlet temperature, inlet pressure, outlet pressure, fuel inlet temperature, outlet temperature, inlet pressure, and outlet pressure.

[0067] ①5mm unit cell: Operating Condition 2: Lubricating oil inlet temperature 105℃; flow rate 15L / min; fuel oil inlet temperature 45℃

[0068] The calculation formulas can still be the previously mentioned formulas (1) to (4). Calculation results for 5mm unit cell condition 2

[0069] The kinetic curve for condition 2 of 5mm unit cell is shown below. Figure 19 As shown.

[0070] ②5.5mm unit cell: Operating Condition 2: Lubricating oil inlet temperature 105℃; flow rate 15L / min; fuel oil inlet temperature 45℃

[0071] The calculation formulas can still be the previously mentioned formulas (1) to (4). Calculation results for 5.5mm unit cell condition 2

[0072] The kinetic curve for condition 2 of 5.5mm unit cell is shown below. Figure 20 As shown.

[0073] ③7mm unit cell: Operating Condition 2: Lubricating oil inlet temperature 105℃; flow rate 15L / min; fuel oil inlet temperature 45℃

[0074] The calculation formulas can still be the previously mentioned formulas (1) to (4). Calculation results for 7mm unit cell condition 2

[0075] The kinetic curve for condition 2 of 7mm unit cell is shown below. Figure 21 As shown.

[0076] Based on a comprehensive analysis of the existing data, it can be observed that the system's dynamic curves exhibit a basically consistent pattern under both operating conditions: as the fuel flow rate gradually increases, the radiator's heat dissipation per unit area continuously rises. Simultaneously, the data also shows that, with a constant fuel flow rate, the heat dissipation per unit area gradually decreases as the unit cell size increases.

[0077] (3) Overpressure test, as shown in the table below: Overpressure test test table

[0078] IV. Conclusion 1. Design feasibility verification: The Gyroid TPMS topology was successfully applied to the lubricating oil radiator, and performance controllability was achieved through parametric design.

[0079] 2. Feasibility of manufacturing confirmed: The AlSi10Mg TPMS heat sink prototype with complex structure and thin wall features was successfully manufactured in an integrated manner using L-PBF technology.

[0080] 3. Performance Advantage Verification: Simulation and experiments jointly confirm that, compared with traditional designs, this TPMS radiator achieves superior overall heat exchange performance in a compact space, thus achieving the core objectives of the project.

Claims

1. A TPMS heat sink design method, characterized in that, Includes the following steps: Step 1: Topology and parametric design of heat exchange core: Based on the target heat transfer performance and spatial constraints, the three-period minimum surface (TPMS) topology is selected as the basic structure of the internal flow channel of the heat exchange core. By adjusting the unit cell size and surface wall thickness parameters, a heat exchange core model with a specific heat transfer area is generated. Step 2: Shell Design and Structural Simulation: Design and encapsulate the shell around the heat exchange core model to form an integrated 3D model of the heat sink, and perform structural strength simulation verification on the shell of the model; Step 3: Additive manufacturing and process optimization: The heat sink is manufactured in an integrated manner using additive manufacturing technology. Specifically, for the manufacturing of the TPMS structure overhang surface, the laser process parameters of contour scanning and path scanning are optimized through experimental design method to suppress the drooping phenomenon on the overhang surface. Step 4: Post-treatment of inner flow channels: The surface of the TPMS inner flow channels of the formed heat sink is treated with multiphase jet polishing process to achieve the predetermined cleanliness level. Step 5: Performance Verification: Through multi-condition heat exchange experiments and overpressure experiments, verify the heat exchange performance and structural reliability of the radiator to ensure that it meets the usage requirements.

2. The TPMS heat sink design method according to claim 1, characterized in that, In step 1, the topology of the TPMS is a Gyroid structure.

3. The TPMS heat sink design method according to claim 1, characterized in that, In step 1, the curved wall thickness of the heat exchange core increases with the increase of the unit cell size.

4. The TPMS heat sink design method according to claim 3, characterized in that, In step 1, the unit cell size is parametrically adjusted to be within the range of 5-7 mm, and the curved surface wall thickness is within the range of 0.76-0.98 mm.

5. The TPMS heat sink design method according to claim 1, characterized in that, In step 3, the additive manufacturing technology specifically adopts metal laser powder bed melting (SLM) technology, which is used to integrally form a heat exchange core containing complex TPMS flow channels based on model data.

6. The TPMS heat sink design method according to claim 1, characterized in that, In step 3, when scanning the overhanging surface, the parameters of the contour scan are set to a first energy density, which is used to form a dense and continuous initial solidification layer on the overhanging surface. The parameters of the path scan are set to a second energy density, which is lower than the first energy density, and are used to remelt and smooth the initial solidification layer, thereby synergistically suppressing the formation of slag.

7. A TPMS heat sink, manufactured using the design method described in any one of claims 1-6, characterized in that, include: The heat exchange core is integrally formed, and its internal flow channels are periodically arranged by the selected TPMS topology. The outer shell encapsulates the heat exchange core and has a fluid interface communicating with the inner flow channel and the inner cavity of the outer shell. The surface of the inner flow channel is a smooth surface that has undergone multiphase jet polishing treatment.

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