Inner-cooling type pneumatic sealing honeycomb structure based on tailor-welding and machining method of inner-cooling type pneumatic sealing honeycomb structure

Abstract

The invention relates to the technical field of gas turbine sealing, and particularly provides an inner-cooling type pneumatic sealing honeycomb structure based on tailor-welding and a machining method of the inner-cooling type pneumatic sealing honeycomb structure. The honeycomb structure comprises a plurality of honeycomb units which are spliced and welded with one another; each honeycomb unit comprises two welding units which are integrally formed; each welding unit comprises a node section and free sections symmetrically arranged at the two ends of the node section in the first direction. A first groove is formed in the surface of the first end, away from the free section, of the node section; the two welding units in the honeycomb unit are in mirror symmetry in the first direction, and the first ends of the two welding units are correspondingly welded; the node sections of the two honeycomb units in mirror symmetry in the first direction are correspondingly welded, and the two first grooves of the two welded node sections are spliced to form a first cooling channel. The problems that when the gas turbine sealing structure is cooled, temperature gradient exists, safety risks are likely to be generated, the punching machining difficulty is large, and the manufacturing cost is high can be solved.

Description

Technical Field

[0001] This invention relates to the field of gas turbine sealing technology, and in particular to a welded internally cooled pneumatic sealing honeycomb structure and its processing method. Background Technology

[0002] The upgrade of aero engines and gas turbines towards higher thrust-to-weight ratios and higher thermal efficiency, based on the Brayton cycle, hinges on increasing turbine inlet temperature and compressor pressure ratio. This exposes hot-end components to extremely demanding operating conditions. The sealing system is the "choke point" for gas path efficiency control, especially the outer ring seal between the high-pressure turbine blade tip and the casing. Its core function is to reduce tip clearance and prevent the ineffective leakage of high-energy combustion gases, directly determining the engine's core performance.

[0003] The metal honeycomb structure used in the current mainstream sealing system is usually made of high-temperature alloy foil strips. The foil strips are first processed into a regular hexagonal honeycomb prototype through rolling and stamping processes. Then, brazing and resistance welding are used to complete the splicing between the foil strips and the fixation of the honeycomb to the back plate to form an overall honeycomb structure. If a cooling structure is to be added, additional drilling and perforation processing is required on the formed ultra-thin honeycomb wall. This structure has the following defects: (1) Back impact cooling only acts on the back plate of the honeycomb structure. The heat conduction path is long and the thermal resistance is large, which makes the honeycomb structure form a temperature gradient with high temperature at the top. It is prone to oxidation and embrittlement during long-term service. When the blade tip is scraped, the slag will cause safety risks; (2) The smooth straight wall structure causes the airflow permeability effect. The airflow energy dissipation is poor and the circumferential swirl is weak. The labyrinth seal's step-by-step pressure reduction effect fails. The turbulence and energy loss are insufficient, which increases the fuel consumption rate; (3) The honeycomb wall is extremely thin, which makes it difficult to control the drilling depth and has low efficiency, making it impossible to mass-produce. Although 3D printing can realize complex structures, it has low efficiency and high cost. The cost performance of large-area consumable parts is extremely poor, making it difficult to commercialize.

[0004] There is currently no effective solution to the problem that the gas turbine sealing structure has a temperature gradient during cooling, which can easily lead to safety risks, and that drilling and processing are difficult and costly. Summary of the Invention

[0005] The present invention provides a welded internal cooling pneumatic sealing honeycomb structure and its processing method, which at least solves the problems of temperature gradient during cooling of gas turbine sealing structures, which easily leads to safety risks, and the high difficulty and cost of drilling and processing.

[0006] To achieve the above objectives, the present invention provides the following technical solution:

[0007] This invention provides a welded, internally cooled, pneumatically sealed honeycomb structure, comprising: a plurality of welded honeycomb units; each honeycomb unit comprising two integrally formed welding units; each welding unit comprising: a node segment, and free segments symmetrically arranged at both ends of the node segment along a first direction; the free segments are located on the same side of the node segment; the extension direction of the free segments forms a first angle between 60° and 150° with the node segment; a first groove is provided on the surface of the node segment away from the first end of the free segment; the first end is the end of the free segment away from the node segment; the first groove penetrates the node segment along a second direction; the second direction is perpendicular to the first direction; two welding units in the honeycomb unit are mirror-symmetrical along the first direction, and the first ends of the two welding units are welded to each other; the node segments of the two mirror-symmetrical honeycomb units along the first direction are welded to each other, and the two first grooves of the two welded node segments are joined to form a first cooling channel.

[0008] Preferably, the welding unit further includes: a welding segment; the welding segment is symmetrically arranged on both sides of the two free segments along the first direction; the welding segment is 1 / 2 of the node segment, including a straight segment and a groove segment; one end of the straight segment is connected to the first end, and the other end is connected to the groove segment; the groove segment and the free segment are located on the same side of the welding segment; two welding segments that are mirror-symmetrical along the first direction in each honeycomb cell are welded accordingly, and the two groove segments of the two welded welding segments are spliced ​​to form the second groove of the honeycomb cell; two second grooves of two honeycomb cells that are mirror-symmetrical along a third direction are welded accordingly, and a second cooling channel is formed between the two welded second grooves; the third direction is perpendicular to the first direction and the second direction.

[0009] Preferably, the wall surface of the free section is provided with at least one aerodynamic drag-increasing structure; the aerodynamic drag-increasing structure includes any one or more combinations of flow guide ribs, vortex generator protrusions, and discontinuous dimples; the second included angle between the extension direction of the aerodynamic drag-increasing structure and the length direction of the free section is between 10 degrees and 45 degrees.

[0010] Preferably, the cross-sectional shape of the cooling channel is circular, elliptical, or rhomboid.

[0011] Preferably, the cross-sectional shape of the first cooling channel is circular; the thickness of each segment of the welding unit is uniform, all being t; the hydraulic diameter D of the first cooling channel is... h The ratio of the thickness to the given thickness t satisfies: 3 ≤ D h / t≤8.

[0012] Preferably, the honeycomb structure further includes a back plate; the back plate is connected to one end of each of the honeycomb cells in the second direction, and the back plate is provided with air inlets communicating with each of the cooling channels for supplying cooling air to the honeycomb structure.

[0013] Preferably, the two welded node segments are connected by brazing, and brazing material is filled between the connecting portions of the two node segments.

[0014] Another aspect of the present invention provides a processing method for an internally cooled pneumatically sealed honeycomb structure based on welding, comprising the following steps: stamping a plurality of integrally formed welding units on a metal plate; wherein, the welding unit comprises: a node segment, and free segments symmetrically arranged at both ends of the node segment along a first direction; the free segments are arranged on the same side of the node segment; the extension direction of the free segments and the first angle between the extension direction of the free segments and the node segment are between 60° and 150°; a first groove is provided on the surface of the node segment away from the first end of the free segments; the first end is the end of the free segments away from the node segment; the first groove penetrates the node segment along a second direction; the second direction is perpendicular to the node segment. Perpendicular to the first direction; any two of the welding units are arranged mirror-symmetrically along the first direction to form a honeycomb unit, resulting in a plurality of honeycomb units; each of the honeycomb units is assembled to form a honeycomb structure with cooling channels, and each of the cooling channels is filled with a ceramic-based flow barrier; wherein, the cooling channel includes a first cooling channel; the first cooling channel is obtained by assembling the first grooves of two honeycomb units that are mirror-symmetrical along the first direction; after the ceramic-based flow barrier is dried and cured, the connection nodes of adjacent honeycomb units are welded; after welding is completed, the ceramic-based flow barrier in the cooling channel is removed to obtain the final honeycomb structure.

[0015] Preferably, any two welding units are arranged in a mirror-symmetrical manner along the first direction to form a honeycomb unit, comprising the following steps: arranging any two welding units in a mirror-symmetrical manner along the first direction; joining two welded segments from the two welding units that are mirror-symmetrical along the first direction, such that the grooved segments of the two welded segments form a second groove, thus obtaining a honeycomb unit; wherein, the welded segments are symmetrically arranged on both sides of the node segment along the first direction; the welded segment is 1 / 2 of the node segment, including a straight segment and a grooved segment; one end of the straight segment is connected to the first end, and the other end of the straight segment is connected to the grooved segment; the grooved segment and the free segment are located on the same side of the welded segment.

[0016] Preferably, the process of assembling the individual cellular units to form a cellular structure with cooling channels includes the following steps: arranging any two cellular units in a mirror-symmetrical manner along the first direction, and assembling the two first grooves of the two cellular units to form a first cooling channel; arranging any two cellular units in a mirror-symmetrical manner along a third direction, and assembling the two second grooves of the two cellular units to form a second cooling channel, thereby obtaining a cellular structure with the first cooling channel and the second cooling channel.

[0017] Compared with the prior art, the above-described technical solution of the present invention has the following advantages:

[0018] This invention provides a welded, internally cooled, pneumatically sealed honeycomb structure and its processing method. It uses integrally formed welding units as basic components. First, the welding units are assembled and welded to form honeycomb units. Then, multiple sets of honeycomb units are welded together to form an overall honeycomb structure. Compared to a single stamped honeycomb unit, this invention results in lower forming stress, higher dimensional accuracy and assembly fit, and superior structural connection strength and impact resistance. A first groove is prefabricated at the node segment of the welding unit. When adjacent honeycomb units are welded, the corresponding first grooves precisely connect to form a through-type internal cooling channel, achieving uniform internal cooling. This effectively shortens the heat conduction path, eliminates structural temperature gradients, helps to overcome the temperature limits of the honeycomb structure, and improves service safety. Simultaneously, this invention uses prefabricated first grooves to form cooling channels, eliminating the need for secondary drilling on the formed honeycomb thin wall, fundamentally solving the problems of high drilling difficulty, uncontrollable precision, and low processing efficiency. The welding units can be standardized and prefabricated by stamping, simplifying the overall welding process, resulting in high processing efficiency and controllable production costs. This not only overcomes the commercial shortcomings of low efficiency and high cost of 3D printing but also makes it more suitable for mass production and engineering applications. Attached Figure Description

[0019] To more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the accompanying drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are merely some embodiments of the present invention, and those skilled in the art can obtain other embodiments based on these drawings without creative effort.

[0020] Figure 1 This is a schematic diagram of a welded, internally cooled, pneumatically sealed honeycomb structure, according to an embodiment of the present invention.

[0021] Figure 2 This is a three-dimensional structural schematic diagram of a single welding unit according to an embodiment of the present invention.

[0022] Figure 3This is a schematic diagram of the splicing between multiple welding units in an embodiment of the present invention.

[0023] Figure 4 This is a schematic diagram of the second included angle between the extension direction of the aerodynamic drag-increasing structure and the length direction of the free segment in an embodiment of the present invention.

[0024] Figure 5 This is a schematic diagram showing the flow direction of cooling airflow after the cellular unit and backplate are connected according to an embodiment of the present invention.

[0025] Figure 6 This is a schematic diagram showing the flow direction of the cooling airflow after the honeycomb structure of an embodiment of the present invention is installed in the wear groove after the test run.

[0026] Figure 7 This is a schematic diagram of the structure of the first cooling channel after it is filled with a ceramic-based flow barrier, according to an embodiment of the present invention.

[0027] Figure 8 This is a schematic flowchart illustrating a processing method for an internally cooled pneumatically sealed honeycomb structure based on welding, according to an embodiment of the present invention.

[0028] Figure reference numerals:

[0029] 100. Cellular unit; 200. Welded unit; 210. Node segment; 211. First groove; 220. Free segment; 221. Pneumatic drag-increasing structure; 230. Welded segment; 231. Straight segment; 232. Groove segment; 310. First cooling channel; 320. Second cooling channel; 400. Back plate; 410. Air inlet; 500. Wear groove after test run; 600. Ceramic-based flow retardant. Detailed Implementation

[0030] Embodiments of the present invention will now be described in more detail with reference to the accompanying drawings. While some embodiments of the present invention are shown in the drawings, it should be understood that the present invention can be implemented in various forms and should not be construed as limited to the embodiments set forth herein. Rather, these embodiments are provided to provide a more thorough and complete understanding of the present invention. It should be understood that the drawings and embodiments of the present invention are for illustrative purposes only and are not intended to limit the scope of protection of the present invention.

[0031] The related metal honeycomb technology is typically made using high-temperature alloy foil strips such as Hastelloy X and GH536. Although the material itself has a high melting point, in order to meet the requirements of next-generation high-performance engines, in the gas environment of up to 1600K or even higher, the metal honeycomb must rely on cooling.

[0032] A common cooling method in related technologies is back-impact cooling, where cold air impacts the honeycomb backplate 400. However, due to the relatively high height of the honeycomb structure (typically 3mm~10mm) and the extremely thin metal walls (0.05mm~0.10mm), the heat conduction path is long, resulting in extremely high thermal resistance. This leads to a fatal temperature gradient: the backplate 400 is very cold, but the top of the honeycomb core in contact with the combustion gas remains at an extremely high temperature.

[0033] Therefore, prolonged high temperatures cause severe oxidation and spalling at the top of the honeycomb structure, making the material brittle. If blade tip scraping occurs, large pieces of debris can easily flake off, potentially triggering a dangerous "titanium fire" or damaging downstream blades. Furthermore, the lack of effective cooling also limits further increases in the engine turbine inlet temperature.

[0034] During engine testing and subsequent operation, due to centrifugal force and thermal expansion, the high-speed rotating turbine blades radially scrape the stationary honeycomb seal, forming an annular wear groove on the honeycomb surface that matches the blade tip trajectory. Ideally, the blade tip runs deeply embedded in this groove, using the "groove effect" to block airflow.

[0035] However, the metal honeycomb in related technologies is composed of regular hexagonal grids with smooth and vertical pore walls. Even with the formation of wear grooves, its sealing efficiency remains limited, mainly in the following two aspects:

[0036] Significant air permeability effect: Leaking airflow mainly flows through the tiny gap between the blade tip and the bottom of the wear groove. In traditional honeycomb systems, the groove bottom consists of a series of open hexagonal cavities. When high-speed airflow passes through these smooth open cavities, it tends to "cross" directly over the cavities without penetrating deep into them to form energy-dissipating vortices. This phenomenon is known as the "air permeability effect" or "carryover effect," which results in the ineffective dissipation of the airflow's kinetic energy and a low drag coefficient.

[0037] Insufficient circumferential flow resistance: The leaking airflow not only has axial velocity but also includes circumferential swirl that is not completely eliminated. Within the wear groove, the smooth honeycomb straight walls cannot provide sufficient resistance to this circumferential airflow. The airflow rotates at high speed within the groove and escapes axially, failing to fully utilize the labyrinth seal's intended step-by-step pressure reduction function.

[0038] While the honeycomb structure in the related technology can provide a physical "groove", its microstructure is too smooth and regular, and its "roughness" is insufficient. It cannot create sufficiently strong turbulence and energy loss at the blade tip gap, so the fuel consumption rate under actual operating conditions still needs to be reduced.

[0039] To address cooling and aerodynamic issues, some technologies involve perforating the honeycomb walls to introduce film cooling. However, for molded honeycombs with a wall thickness of only 0.05mm, controlling the depth of perforation using electrical discharge machining (EDM) or laser drilling is extremely difficult, easily resulting in penetration of adjacent walls or damage to the backplate. Furthermore, the processing efficiency is extremely low, making mass production impossible. While metal 3D printing (such as selective laser melting (SLM) can create honeycombs with complex internal flow channels, its printing efficiency is low, surface roughness is high (affecting aerodynamics), and powder materials are extremely expensive. For such large-area, easily damaged sealing components, the cost-effectiveness of 3D printing is extremely low, making large-scale adoption in commercial engines difficult.

[0040] To improve the cooling effect of gas turbine sealing structures and reduce temperature gradients, drilling difficulty, and manufacturing costs, embodiments of this invention provide a welded internally cooled aerodynamic sealing honeycomb structure and its processing method.

[0041] Among them, such as Figures 1 to 3 As shown, the embodiment of the present invention provides a welded internally cooled pneumatically sealed honeycomb structure, comprising: a plurality of welded honeycomb units 100; each honeycomb unit 100 includes two integrally formed welding units 200; the welding unit 200 includes: a node segment 210, and free segments 220 symmetrically arranged at both ends of the node segment 210 along a first direction; the free segments 220 are arranged on the same side of the node segment 210; the extension direction of the free segment 220 and the first angle between the node segment 210 and the node segment 210 are between 60° and 150°; the node segment 210 is located away from the free segment 210. A first groove 211 is provided on the surface of the first end of 20; the first end is the end of the free segment 220 away from the node segment 210; the first groove 211 penetrates the node segment 210 along the second direction; the second direction is perpendicular to the first direction; two welding units 200 in the honeycomb unit 100 are mirror-symmetrical along the first direction, and the first ends of the two welding units 200 are welded to each other; the node segments 210 of the two honeycomb units 100 that are mirror-symmetrical along the first direction are welded to each other, and the two first grooves 211 of the two welded node segments 210 are spliced ​​together to form a first cooling channel 310.

[0042] Specifically, the honeycomb unit 100 is the basic module that constitutes the overall honeycomb structure. The outer contour of the honeycomb unit 100 is specifically designed according to the sealing requirements of the aerodynamic sealing conditions, the structural stress characteristics, and the cooling channel layout. It can be a conventional polygonal structure such as a triangle, quadrilateral, hexagon, or rhombus, or an irregular structure adapted to special assembly space and airflow environment.

[0043] Furthermore, the honeycomb unit 100 is preferably a hexagonal structure, which has the advantages of stable structural mechanical properties, uniform overall stress, large sealing coverage area, and excellent adaptability to aerodynamic flow field. At the same time, the hexagonal honeycomb unit 100 has a high degree of fit when spliced, which can maximize the use of assembly space while ensuring structural strength, and significantly improve the sealing effect and structural stability of the pneumatic seal.

[0044] The welding methods can include: brazing, laser welding, resistance welding, and electron beam welding.

[0045] Welding unit 200 is the basic prefabricated component that makes up honeycomb unit 100. It is usually made of thin-walled metal plate through forming process. It is suitable for the high temperature, high pressure and high speed airflow service environment of equipment such as aero-engines and gas turbines. The materials are mostly high-temperature alloys, heat-resistant stainless steel, titanium alloys and other high-performance metal materials. The thickness is generally 0.05mm to 0.1mm. The thin-wall design not only meets the engineering requirements of lightweight structure, but also ensures the forming toughness of the component, which is convenient for welding operations and precise assembly.

[0046] Integrated molding refers to the process by which the node segment 210 and the free segment 220 of the welding unit 200 are formed in one go through integrated processes such as stamping, overall bending, and precision casting. This can ensure the continuity of the overall structure of the welding unit 200 and improve the overall reliability and service life of the components.

[0047] The node segment 210 serves to connect and fix the welding units 200 and the honeycomb units 100, and is also responsible for transmitting external forces to the overall structure. It also forms the basis for the first cooling channel 310. The first groove 211 can be obtained through precision machining methods such as stamping, precision milling, wire cutting, and laser etching.

[0048] The first direction is the length direction of node segment 210. The second direction is the width direction of node segment 210. Free segments 220 are symmetrically arranged at both ends of node segment 210 along the first direction. That is, the two free segments 220 are arranged at the two ends of the length direction of node segment 210 with the central axis of node segment 210 in the second direction as the symmetry reference, forming an axisymmetric structural layout. This ensures that the stress distribution of welding unit 200 is uniform when under force, and avoids deformation and fracture problems caused by unilateral force.

[0049] The free segments 220 are located on the same side of the node segments 210, that is, both free segments 220 extend toward the same surface of the node segments 210, rather than being distributed to the upper and lower sides of the node segments 210, providing a structural basis for the subsequent mirror welding of the two welding units 200 to form a closed honeycomb unit 100 profile.

[0050] The first angle between the extension direction of the free segment 220 and the node segment 210 is the angle between the length direction of the free segment 220 and the length direction of the node segment 210. If the first angle is 60°, the two free segments 220 and one node segment 210 form a triangular structure, which can obtain a triangular honeycomb unit 100; if the first angle is 90°, the two free segments 220 are parallel to each other, which can obtain a quadrilateral honeycomb unit 100; if the first angle is 120°, the two welded units 200 can be assembled in a mirror symmetry along the first direction to obtain a hexagonal honeycomb unit 100; if the first angle is 150°, the extension angle of the two free segments 220 is close to straight, and after the two welded units 200 are assembled in a mirror symmetry along the first direction, a rhomboid irregular honeycomb unit 100 can be formed. This structure can adapt to special airflow guidance and sealing gap compensation requirements, optimize the aerodynamic flow field distribution under specific working conditions, and improve the working condition adaptability of the structure.

[0051] Therefore, the embodiments of the present invention limit the range of the first included angle to between 60° and 150°, which can cover the mainstream and practical honeycomb unit 100 structural forms in engineering such as triangles, quadrilaterals, hexagons, and rhombuses. The corresponding honeycomb unit 100 shape can be flexibly selected according to different aerodynamic sealing conditions, load-bearing requirements, and cooling medium flow requirements, which greatly improves the versatility and adaptability of the structure. At the same time, this angle range can ensure the connection strength between the free segment 220 and the node segment 210, avoid stress concentration at the connection part due to the included angle being too small, and insufficient structural support stiffness due to the included angle being too large, and take into account the feasibility of the structure's molding, processing convenience, and actual performance.

[0052] The first groove 211 can be processed by high-precision machining methods such as stamping, precision milling, electrical discharge machining, and chemical etching. The first groove 211 is set on the surface of the first end of the node segment 210 away from the free segment 220, so that when the welding unit 200 is assembled into the honeycomb unit 100, the first groove 211 is on the outer surface of the honeycomb unit 100, so as to facilitate the assembly of the first cooling channel 310 by welding the honeycomb unit 100.

[0053] With the first direction as the axis of symmetry, two welding units 200 with identical specifications and structures are mirrored, so that the first ends of the two free segments 220 of one welding unit 200 are precisely fitted and positioned with the first ends of the corresponding two free segments 220 of the other welding unit 200. Then, the fitted first ends are firmly welded by selected welding methods such as brazing or laser welding. The node segments 210 of the two welding units 200 are synchronously formed to form corresponding fits, and finally enclosed to form a closed, regular outline and precise size honeycomb unit 100. This welding method can ensure the strength of each connection joint of the honeycomb unit 100, and the forming process is simple and easy to realize automated production and dimensional accuracy control.

[0054] Two cellular units 100 are arranged symmetrically in a mirror image along a first direction. The corresponding node segments 210 of the two units are welded together, and the first grooves 211 on the two welded node segments 210 are precisely aligned to form a first cooling channel 310. This splicing and welding method can ensure that the first cooling channel 310 is regular and unobstructed, achieve uniform heat dissipation throughout the entire area, protect the node segments 210 from high temperature damage, enhance structural stability, and does not occupy external space, thus balancing cooling and sealing performance.

[0055] After two honeycomb units 100 are mirror-symmetrically assembled along the first direction, a two-layer stacked honeycomb structure can be obtained. Next, based on the shape of the honeycomb units 100, the requirements for pneumatic sealing, structural integrity, and assembly compatibility, the remaining honeycomb units 100 are assembled in corresponding directions longitudinally and laterally, ensuring precise alignment of the welding units 200 of each honeycomb unit 100. The free sections 220 or node sections 210 are securely welded, while the first groove 211 is simultaneously aligned to form a continuous cooling channel, ultimately constituting a complete internally cooled, pneumatically sealed honeycomb structure. Because the first groove 211 is a through groove, an air film pore can naturally form at one end of the honeycomb structure in the second direction.

[0056] The internally cooled pneumatically sealed honeycomb structure based on welding provided by the present invention uses an integrally formed welding unit 200 as the basic component. First, the welding unit 200 is assembled and welded to form a honeycomb unit 100. Then, multiple sets of honeycomb units 100 are welded together to form an overall honeycomb structure. Compared with the integral stamped complete honeycomb unit 100, the present invention has lower forming stress, higher dimensional accuracy and assembly fit, and better structural connection strength and impact resistance.

[0057] The welding unit 200 node segment 210 prefabricates the first groove 211. When adjacent honeycomb units 100 are welded together, the corresponding first groove 211 is precisely spliced ​​to form a through-type built-in cooling channel, realizing uniform internal cooling, effectively shortening the heat conduction path, eliminating the structural temperature gradient, helping to break through the temperature limit of the honeycomb structure, and improving service safety.

[0058] Meanwhile, the present invention uses prefabricated first grooves 211 to form cooling channels, eliminating the need for secondary drilling on the formed honeycomb thin wall, thus fundamentally solving the problems of high drilling difficulty, difficulty in controlling precision, and low processing efficiency; the welding unit 200 can be standardized and prefabricated by stamping, the overall welding process is simple, the processing efficiency is high, and the production cost is controllable, which not only makes up for the commercial defects of low efficiency and high cost of 3D printing, but also makes it more suitable for mass production and engineering applications.

[0059] Further, the welding unit 200 of the present invention preferably further includes: a welding segment 230; the welding segment 230 is symmetrically arranged on both sides of the two free segments 220 along the first direction; the welding segment 230 is half of the node segment 210, including a straight segment 231 and a groove segment 232; one end of the straight segment 231 is connected to the first end, and the other end is connected to the groove segment 232; the groove segment 232 and the free segment 220 are located on the same side of the welding segment 230; two welding segments 230 that are mirror-symmetrical along the first direction in each honeycomb unit 100 are welded accordingly, and the two groove segments 232 of the two welded welding segments 230 are spliced ​​to form the second groove of the honeycomb unit 100; two second grooves of two honeycomb units 100 that are mirror-symmetrical along a third direction are welded accordingly, and a second cooling channel 320 is formed between the two welded second grooves; the third direction is perpendicular to the first direction and the second direction.

[0060] Specifically, node segment 210 is composed of a straight portion and a first groove 211, forming a symmetrical thin-walled structure with a through groove; welded segment 230 is half of node segment 210, and its length and cross-sectional profile perfectly match half of node segment 210. Straight segment 231 corresponds to half of the straight portion of node segment 210, and groove segment 232 corresponds to half of the first groove 211.

[0061] The groove segment 232 and the free segment 220 are located on the same side of the welding segment 230, so that when the two welding units 200 are arranged in a mirror symmetrical manner along the first direction, the two groove segments 232 can be joined together to form a second groove.

[0062] The third direction, which is the thickness direction of the honeycomb structure perpendicular to the plane formed by the first and second directions, is also the splicing direction of the lateral expansion of the honeycomb unit 100.

[0063] Furthermore, such as Figure 2 , Figure 3 As shown, by setting the welded section 230 as half of the node section 210, and simultaneously moving the grooved section 232 of the welded section 230 away from the free section 220, when the welded sections 230 of two honeycomb units 100 that are mirror-symmetrical along the third direction are joined, a node section 210 can be obtained. When two two-layer stacked honeycomb structures are mirror-symmetrical along the third direction and the welded sections 230 are welded accordingly, a second cooling channel 320 is formed between the two second grooves, and a fifth honeycomb unit 100 is naturally formed in the middle of the four honeycomb units 100. This significantly improves the overall density, structural connection strength, and sealing reliability of the honeycomb structure, while achieving a uniform and dense distribution of cooling channels, further enhancing the overall cooling effect.

[0064] In this embodiment of the invention, by welding two honeycomb units 100 that are mirror-symmetrical along a third direction together through a groove section 232, the free section 220 can be in a free state without being welded, thereby ensuring that the free section 220 has good elastic deformation capability, which can adapt to assembly gaps, thermal expansion deformation and airflow disturbances in working conditions, realize adaptive sealing compensation, and improve the dynamic adaptability and sealing effect of the pneumatic sealing structure.

[0065] The welding unit 200 described in the embodiment of the present invention, by adding a welding section 230, can symmetrically weld together a second groove within a single honeycomb unit 100, and then, in conjunction with the honeycomb units 100 along a third direction, construct a second cooling channel 320 that is identical in shape and size to the first cooling channel 310. At the same time, the welding section 230 provides a dedicated welding mating part for the multi-directional splicing of the honeycomb units 100, which not only ensures the positioning accuracy and welding firmness when splicing in different dimensions, but also realizes the synchronous forming of the cooling channel and the structure splicing, simplifying the processing steps of the multi-dimensional cooling structure.

[0066] Furthermore, combined Figure 4 As shown, the preferred honeycomb structure provided in the embodiment of the present invention has at least one aerodynamic drag-increasing structure 221 provided on the wall surface of the free segment 220; the aerodynamic drag-increasing structure 221 includes any one or more combinations of guide ribs, vortex generator protrusions, and discontinuous dimples; the second included angle between the extending direction of the aerodynamic drag-increasing structure 221 and the length direction of the free segment 220. It is between 10 and 45 degrees.

[0067] The aerodynamic drag-increasing structure 221 is a general term for the functional structures installed on the wall of the free section 220 to enhance the aerodynamic sealing effect in this embodiment of the invention. By installing the aerodynamic drag-increasing structure 221 on the wall of the free section 220, the stability of the leakage jet entering the honeycomb structure can be disrupted, inducing the airflow to generate secondary vortices, thereby significantly increasing the flow resistance coefficient and reducing airflow leakage.

[0068] Guide ribs are elongated or segmented protrusions on the free section 220 wall surface, typically rectangular or trapezoidal in cross-section. These guide ribs direct airflow in an orderly, oblique direction through linear protrusions, increasing airflow resistance and continuously scouring the wall surface to enhance heat transfer. They are suitable for large-area, high-uniformity applications with strict flow resistance limitations in conventional sealing and cooling areas.

[0069] The vortex generator protrusions are small, discrete protrusions on the wall of the free section 220, commonly in the shape of airfoils, triangles, or hemispheres. Their core function is to induce regular localized vortices in the airflow, efficiently disrupting the laminar boundary layer, thereby significantly increasing local flow resistance and heat transfer efficiency. This makes them suitable for scenarios requiring strong localized cooling and sealing, such as critical areas with extremely high heat loads and high leakage risks (e.g., welded joints, near node section 210).

[0070] Discontinuous dimples are discrete micro-dimples artificially machined on the wall of the free section 220 (unrelated to dimples caused by material fracture). These independent dimples create localized turbulence, increasing flow resistance while enhancing heat transfer. Because the discontinuous design does not compromise the matrix continuity and elastic deformation capability of the free section 220, it can be adapted to thin-walled elastic regions such as the free section 220, satisfying the requirements of aerodynamic drag enhancement, enhanced heat transfer, and adaptive sealing.

[0071] The second angle between the extension direction of the aerodynamic drag-increasing structure 221 and the length direction of the free segment 220 Setting the angle between 10 and 45 degrees is the optimal choice to balance drag enhancement, airflow stability, and structural performance. If the second angle is less than 10 degrees, the structure is almost parallel to the mainstream airflow direction, which cannot effectively disrupt the laminar boundary layer. The drag enhancement and heat transfer enhancement effects are weak and cannot meet the sealing requirements. If the second angle is greater than 45 degrees, it will cause the airflow to separate prematurely, forming a disordered vortex dead zone, causing flow field turbulence and a sudden increase in local pressure, which will increase the risk of airflow leakage. At the same time, excessive stress concentration will weaken the elasticity and structural strength of the free section 220.

[0072] When the second included angle Within the range of 10 to 45 degrees, it can efficiently induce secondary eddies and significantly increase the flow resistance coefficient, while maintaining the stability of airflow and avoiding blockage or turbulence. At the same time, it adapts to the thin-walled elastic characteristics of the free section 220, without generating excessive stress concentration, thus ensuring the self-adaptive sealing capability of the free section 220.

[0073] The honeycomb structure provided in this invention, by setting the above structure, effectively disrupts the stability of the leaking jet, induces secondary eddies to significantly increase the flow resistance coefficient, greatly reduces airflow leakage, and enhances the aerodynamic sealing effect. On the other hand, through the turbulence effect of different structures, it disrupts the laminar boundary layer of the cooling medium, significantly improves the wall heat transfer efficiency, reduces the structural operating temperature, and avoids high-temperature oxidation and embrittlement. At the same time, the discontinuous design and reasonable angle ensure the elastic deformation capability of the free section 220, which can adaptively compensate for assembly gaps and thermal deformation, further improving the sealing reliability, and ultimately achieving synergistic optimization of aerodynamic sealing, efficient cooling and structural stability.

[0074] Furthermore, multiple aerodynamic drag-increasing structures 221 can be arranged in a staggered manner, that is, in the second direction, the positions of two adjacent aerodynamic drag-increasing structures 221 move back and forth, so that the leaking airflow faces constantly changing directional resistance when crossing the hole wall, thereby maximizing energy dissipation.

[0075] Furthermore, the honeycomb structure provided in the embodiments of the present invention preferably has a cooling channel with a circular, elliptical, or rhomboid cross-sectional shape.

[0076] Specifically, when the cross-sectional shape of the cooling channel is circular, the circular cross-section is uniform in the circumference and has no sharp corners. The ratio of wetted perimeter to flow area is the smallest, resulting in low flow resistance and low pressure loss. The fluid distribution is uniform, there are no stress concentration points, and the ability to resist thermal shock and structural deformation is strong. It is suitable for main cooling channels that are sensitive to flow resistance and require long-distance transportation of cooling media, or for node sections 210 areas that require high structural stability under high temperature and high pressure.

[0077] When the cross-sectional shape of the cooling channel is elliptical, the elliptical cross-section can be adapted to the arc-shaped wall of the free section 220 by adjusting the major and minor axes. Under similar flow areas, it has a larger heat exchange area than a circle, and the increase in flow resistance is controllable. It can be adapted to the free section 220 cooling channel that needs to balance heat exchange efficiency and flow resistance, or splicing parts with limited space.

[0078] When the cross-sectional shape of the cooling channel is rhomboid, the rhomboid cross-section has an angular structure and a relatively large wetted perimeter to area ratio. When the fluid flows through the angular section, it is easy to form local eddies to enhance turbulent heat transfer. Although the flow resistance is slightly higher, the local heat transfer efficiency is significantly improved. It is suitable for areas near welded joints with extremely high local heat loads that require strong cooling, or for key sealing parts that require increased aerodynamic damping.

[0079] Specifically, the cooling channel includes a first cooling channel 310 and a second cooling channel 320. In fact, since the second cooling channel 320 is obtained by symmetrically splicing two second grooves along a third direction, and the second grooves are preferably the same in structure and size as the first groove 211, the first cooling channel 310 and the second cooling channel 320 are preferably the same in structure and size.

[0080] Furthermore, in the preferred embodiment of the present invention, the honeycomb structure has a circular cross-sectional shape for the first cooling channel 310; the thickness of each segment of the welding unit 200 is uniform, all being t; and the hydraulic diameter D of the first cooling channel 310 is... h The ratio of the thickness to the given thickness t satisfies: 3 ≤ D h / t≤8.

[0081] Hydraulic diameter, in fluid mechanics, is the equivalent flow diameter defined to describe the flow characteristics of non-circular cross-section channels. Its core principle is to equate non-circular channels to virtual circular pipes, thereby standardizing the calculation of flow and heat transfer. The formula for calculating hydraulic diameter is: ,in, This refers to the cross-sectional area of ​​the cooling channel. The wetted perimeter is the area where the fluid comes into contact with the wall of the cooling channel.

[0082] Setting the lower limit of the ratio of the hydraulic diameter to the thickness of the first cooling channel 310 to 3 prevents the hydraulic diameter from being too small relative to the thickness of the welding unit 200, avoiding a sharp increase in flow resistance due to an excessively narrow cooling channel, which would obstruct the flow of cooling medium, result in insufficient flow, and fail to meet the heat dissipation requirements of the structure. Setting the upper limit to 8 prevents the hydraulic diameter from being too large relative to the thickness, preventing the cooling medium velocity in the channel from being too low and the laminar boundary layer from becoming too thick, which would significantly reduce the heat exchange efficiency. At the same time, it eliminates the problem of insufficient structural rigidity caused by an excessively wide channel, which could lead to deformation failure under the impact of high-temperature and high-pressure airflow.

[0083] The honeycomb structure provided in the embodiments of the present invention utilizes the hydraulic diameter D of the first cooling channel 310. h The ratio of the thickness t of the welding unit 200 to the thickness t is limited to between 3 and 8, which can effectively balance the flow resistance and heat exchange efficiency of the channel, ensure that the cooling medium flows stably at a suitable flow rate, achieve sufficient and efficient heat dissipation, and at the same time ensure that the welding unit 200 has sufficient structural strength and rigidity, and is compatible with conventional processing technology such as stamping and welding, taking into account the cooling performance, structural reliability and feasibility of engineering production.

[0084] Furthermore, such as Figure 5 As shown, the preferred honeycomb structure provided in the embodiment of the present invention further includes a back plate 400; the back plate 400 is connected to one end of each honeycomb cell 100 in a second direction, and the back plate 400 is provided with an air inlet 410 connected to each cooling channel for supplying cooling air to the honeycomb structure.

[0085] Specifically, the backplate 400 and each cell unit 100 are fixedly connected at the bottom end in the second direction by welding or integral molding. The connection is tightly sealed and there is no gap for cooling gas leakage. The air inlet 410 on the backplate 400 corresponds to each cooling channel of the cell unit 100 and is precisely aligned and connected. The diameter of the air inlet 410 is adapted to the hydraulic diameter of the cooling channel, and the air inlet 410 is evenly distributed along the plane of the backplate 400, covering the bottom area of ​​all cell units 100.

[0086] The top of the cellular unit 100 in the second direction is not additionally blocked or processed. The air film holes are naturally formed directly from the port of the cooling channel. Each air film hole is independent and arranged in a regular manner, forming a continuous and independent cooling air path with the cooling channel below and the air inlet 410 of the back plate 400.

[0087] The honeycomb structure provided by the embodiments of the present invention not only provides reliable support for the honeycomb structure, improving overall rigidity and installation stability, but also enables uniform and efficient supply of cooling air, avoiding air leakage at the connection points. At the same time, the naturally formed air film pores simplify the processing technology, and can form a uniform air film on the sealing mating surface, taking into account cooling efficiency, sealing effect and structural reliability, and reducing manufacturing costs.

[0088] like Figure 6 As shown, the honeycomb structure is installed on the wear groove 500 after engine testing that needs to be sealed, and the wall surface of the top free section 220 of the honeycomb structure is precisely fitted with the friction contact area of ​​the wear groove 500 after testing.

[0089] When the cooling airflow enters the cooling channel from the back of the honeycomb structure through the air supply hole of the back plate 400, it first forms a stable laminar or weakly turbulent flow in the cooling channel, flowing smoothly along the channel axis. At the same time, it performs basic heat exchange through the channel wall, initially removing the heat from the honeycomb structure (internal convection heat exchange). As the airflow advances into the free section 220 region, the flow field begins to interact with the aerodynamic drag-increasing structure 221 on the wall. Finally, the airflow is ejected from the top of the honeycomb core, forming a covering air film on the honeycomb wear surface (external air film cooling).

[0090] Combination Figure 7 As shown, when the airflow passes through the aerodynamic drag-increasing structure 221 of the free section 220, it will disturb the originally smooth laminar boundary layer, causing the airflow to form multi-scale disturbances near the wall, thereby inducing a large number of controllable secondary vortices. These vortices will not only significantly increase the flow resistance coefficient and directly reduce the leakage of the airflow, but also allow the cooling medium to have more sufficient contact and mixing with the wall of the free section 220, greatly improving the convective heat transfer efficiency. Thus, while strengthening the aerodynamic sealing effect, it can effectively reduce the operating temperature of the free section 220 and ensure the reliability of the structure under high temperature and high wear conditions.

[0091] Furthermore, the cross-sectional area of ​​the cooling channel is preferably gradually decreasing from the bottom to the top of the honeycomb structure in the second direction, forming a variable cross-section structure. Since the airflow direction in the cold zone is usually from the back plate 400 to the honeycomb structure, setting a variable cross-section cooling channel can accelerate the outlet airflow and enhance the adhesion of the top air film to the wall.

[0092] Furthermore, when the cooling channel is a variable cross-section structure, in order to ensure the ratio of the hydraulic diameter to the thickness of the first cooling channel 310, the thickness of the welding unit 200 in the embodiment of the present invention gradually decreases from the bottom to the top in the second direction, thereby enabling the honeycomb structure to achieve the gradient stiffness characteristics of "high strength at the root and easy wear at the top".

[0093] Furthermore, the thickness of the welding unit 200 can be gradually reduced by using materials of different thicknesses for splicing, or by chemical corrosion.

[0094] like Figure 8 As shown, the embodiments of the present invention also provide a processing method for a welded, internally cooled, pneumatically sealed honeycomb structure, which can be applied to a welded, internally cooled, pneumatically sealed honeycomb structure as described in the above embodiments. Preferably, the processing method includes the following steps S1 to S5.

[0095] Step S1: A plurality of integrally formed welding units 200 are stamped on a metal plate; wherein, the welding unit 200 includes: a node segment 210, and free segments 220 symmetrically arranged at both ends of the node segment 210 along a first direction; the free segments 220 are arranged on the same side of the node segment 210; the extension direction of the free segment 220 and the first angle between the node segment 210 and the node segment 210 are between 60° and 150°; a first groove 211 is provided on the surface of the node segment 210 away from the first end of the free segment 220; the first end is the end of the free segment 220 away from the node segment 210; the first groove 211 penetrates the node segment 210 along a second direction; the second direction is perpendicular to the first direction.

[0096] Step S2: Arrange any two welding units 200 in a mirror-symmetrical manner along the first direction to form a honeycomb unit 100, and obtain a total of multiple honeycomb units 100.

[0097] Step S3: Assemble the individual honeycomb cells 100 to form a honeycomb structure with cooling channels, and fill each cooling channel with a ceramic-based flow barrier 600; wherein, the cooling channel includes a first cooling channel 310; the first cooling channel 310 is obtained by assembling the first grooves 211 of two honeycomb cells 100 that are mirror-symmetrical along the first direction.

[0098] Step S4: After the ceramic-based flow barrier 600 is dried and cured, the connection nodes of adjacent cell units 100 are welded.

[0099] Step S5: After welding is completed, the ceramic-based flow barrier 600 in the cooling channel is removed to obtain the final honeycomb structure.

[0100] Specifically, the structural composition, shape, and connection relationship of the above-mentioned cellular unit 100 and the welded structure are described in the cellular structure provided in the above embodiments, and will not be repeated here.

[0101] The connection nodes of each cell unit 100 are the connection parts of the cell structure welded together. They include the straight part of the node segment 210 of the two welded units 200 arranged symmetrically along the first direction to form a single cell unit 100, as well as other areas of adjacent cell units 100 that are in contact with each other and used for welding and fixing when multiple cell units 100 are assembled together. They are the key welding positions to ensure the integrity and structural strength of the cell structure.

[0102] Ceramic-based flow inhibitor 600, preferably yttrium oxide (YO) ) or aluminum oxide ( The composite material made by mixing powder and inorganic binder has excellent high temperature resistance. It does not melt at high welding temperatures, does not react with the metal matrix and solder, and has a stable structure after curing. It can also be easily removed by subsequent chemical etching or mechanical vibration, forming a reliable physical barrier without leaving any contamination channels.

[0103] The processing method provided by the present invention, by first filling the cooling channel with ceramic-based flow barrier 600, drying and curing it, and then welding each honeycomb unit 100, can prevent the molten solder during welding from being sucked in by capillary action and blocking the cooling channel.

[0104] Furthermore, the metal plate is preferably a 0.1mm foil strip. The first groove 211 is preferably formed by stamping. The welding method is preferably high-temperature brazing.

[0105] The preferred processing method for the ceramic-based flow barrier 600 is to inject the flow barrier into the channels formed by the interlocking parts using a slurry injection method, and then dry and cure it at 150°C. Methods for removing the ceramic-based flow barrier 600 include chemical etching or mechanical vibration.

[0106] The processing method provided by the embodiments of this invention ensures the dimensional accuracy of the welding unit 200 through integrated stamping, ensures the regularity and symmetry of the cooling channels through mirror splicing, and fills and solidifies the cooling channels with ceramic-based flow-blocking agent 600 by slurry injection. This fundamentally prevents the solder from blocking the channels due to capillary action during welding, thus preserving the integrity of the cooling channels. Furthermore, the flow-blocking agent is heat-resistant and easy to remove. Combined with the precise welding of the connection nodes, this method solves the industry problem of easy clogging during welding of internally cooled honeycomb structures while ensuring the overall connection strength and structural stability of the honeycomb structure. It also improves the product yield, and the processing steps are simple and controllable, making it suitable for large-scale engineering production.

[0107] Further, step S2 of the processing method of this invention, which involves arranging any two welding units 200 in a mirror-symmetrical manner along a first direction to form a honeycomb unit 100, includes the following steps: arranging any two welding units 200 in a mirror-symmetrical manner along a first direction; joining two welded segments 230 in the two welding units 200 that are mirror-symmetrical along the first direction, such that the groove segments 232 of the two welded segments 230 form a second groove, thus obtaining a honeycomb unit 100; wherein, the welded segments 230 are symmetrically arranged on both sides of the node segment 210 along the first direction; the welded segment 230 is half of the node segment 210, including a straight segment 231 and a groove segment 232; one end of the straight segment 231 is connected to the first end, and the other end of the straight segment 231 is connected to the groove segment 232; the groove segment 232 and the free segment 220 are located on the same side of the welded segment 230.

[0108] The processing method provided by the present invention arranges two welding units 200 in a mirror-symmetrical manner along a first direction, and precisely assembles the corresponding welding segments 230 and the groove segments 232 together to form a second groove. This ensures that the structural height of a single honeycomb unit 100 is symmetrical, and ensures that the cross-sectional dimensions and orientation of the second groove are regular and uniform. At the same time, it ensures that the forces on each part of the honeycomb unit 100 are balanced, avoiding structural deformation caused by assembly deviations. This provides a reliable unit foundation for the subsequent assembly of the overall honeycomb structure and the precise forming of the second cooling channel 320, ensuring the product's dimensional accuracy and structural consistency.

[0109] Furthermore, in step S3 of the processing method of the present invention, the process of assembling the individual honeycomb cells 100 to form a honeycomb structure with cooling channels includes the following steps: arranging any two honeycomb cells 100 in a mirror-symmetrical manner along a first direction, and assembling the two first grooves 211 of the two honeycomb cells 100 to form a first cooling channel 310; arranging any two honeycomb cells 100 in a mirror-symmetrical manner along a third direction, and assembling the two second grooves of the two honeycomb cells 100 to form a second cooling channel 320, thereby obtaining a honeycomb structure with the first cooling channel 310 and the second cooling channel 320.

[0110] The above-mentioned processing method provided by the embodiments of the present invention arranges the honeycomb units 100 in a mirror symmetrical manner along the first direction and the third direction, respectively. By precisely assembling the corresponding first groove 211 and the second groove, a first cooling channel 310 and a second cooling channel 320 are formed respectively, which can construct a through and uniformly distributed multi-dimensional internal cooling channel network, ensuring that the forming quality of each channel is consistent and there is no misalignment or blockage.

[0111] The connection nodes between each cell unit 100 are on the node segment 210 and the welded segment 230, while the free segment 220 is not welded. This method preserves the thin-walled elastic matrix of the free segment 220 and avoids interference and damage to its morphology and deformation performance by welding stress and solder. As a result, the aerodynamic drag-increasing structure 221 located in the free segment 220 can stably perform the aerodynamic sealing function of disrupting the stability of the leakage jet, inducing secondary eddies, increasing the flow resistance coefficient to reduce airflow leakage, and enhancing the cooling effect of wall convective heat transfer. At the same time, it can ensure that the free segment 220 maintains good elastic deformation capability throughout the process. It can achieve adaptive dynamic compensation with the change of the gap of the sealing pair and the thermal expansion deformation under the working state. At the same time, it ensures that the morphological integrity and function of the aerodynamic drag-increasing structure 221 are not affected, and continuously and stably achieves the synergistic effect of aerodynamic drag increase, efficient heat dissipation and dynamic sealing.

[0112] The following is a honeycomb structure for the first-stage outer ring sealing of a high-pressure turbine in an aero-engine, manufactured based on the honeycomb structure provided in the embodiments of the present invention, including:

[0113] The base material for welding unit 200 is GH536 nickel-based high-temperature alloy foil. This material has excellent resistance to high-temperature oxidation and is suitable for... The work environment.

[0114] Material specifications: Initial thickness of foil strip =0.10mm ( ).

[0115] Cellular cell 100 specifications: Cell shape: regular hexagon. Cell side margin: S = 1.6 mm (1 / 16 inch). Cellular core height: H = 10 mm.

[0116] Backplate 400 specification: GH536 alloy plate with a thickness of 1.5mm is selected, and an array of air supply holes with a diameter of 0.6mm is pre-made on it. The hole spacing is consistent with the spacing of the honeycomb microchannel.

[0117] Node segment 210 length (Corresponding to one side of the hexagon).

[0118] The parameters of the first groove 211 are: radius R = 0.25 mm, depth d = 0.15 mm.

[0119] The straight portion of node segment 210: its width on both sides of the first groove 211 is approximately 0.25 mm, serving as the contact surface for subsequent resistance spot welding and brazing.

[0120] Dimensions of free segment 220: Length .

[0121] Aerodynamic drag-increasing structure 221: Three parallel guide ribs are stamped out on the wall of the free section 220 by a die.

[0122] The parameters of the guide rib are: height hr=0.15mm, width wr=0.20mm.

[0123] Angle and direction: The second angle between the extension direction of the guide rib and the length direction of the free end. Crucially, the tilt direction is designed to be opposite to the direction of the engine's main combustion gas flow, thus guiding the leaking airflow to generate a reverse vortex and maximizing flow resistance.

[0124] Sealing structure: The straight sections of the node segments 210 on both sides of the cooling channel are tightly connected by brazing filler metal to form a "sandwich"-like structure. Even if high-pressure cold air (e.g., 20 bar-30 bar) is introduced into the microchannel, the welds on both sides can ensure that no lateral leakage occurs.

[0125] The cooling channel is formed by joining two first grooves 211 or two second grooves, and has a diameter of A complete circular channel.

[0126] Bottom interface: When the bottom end of the honeycomb structure is brazed to the back plate 400 in the second direction, the air supply hole (0.6mm in diameter) on the back plate 400 is slightly larger than the diameter of the cooling channel, forming a tolerance design to ensure that even with minor assembly errors, the cold air can smoothly enter the microchannel.

[0127] Top outlet: After the honeycomb structure is manufactured, the top of the cooling channel may be closed or deformed in the initial state. Through the final surface grinding process, about 0.2mm of excess material at the top of the honeycomb is removed, thereby neatly cutting the top of the microchannel to form a circular air film cooling hole.

[0128] To ensure the manufacturability of the structure, the honeycomb structure in this embodiment is preferably manufactured using the following process steps, including:

[0129] (1) Precision stamping: Using multi-station progressive dies, wave forming, semi-circular groove stamping and oblique rib stamping are completed simultaneously on 0.1mm foil strip.

[0130] (2) Stacking and spot welding: Stack the metal strips layer by layer. For each layer, use a resistance spot welding machine to fix it in the flat area of ​​the node. The spot welding position should avoid the middle semi-circular groove to prevent flattening of the flow channel.

[0131] (3) Key steps in filling the flow barrier agent:

[0132] To prevent the molten filler metal from being drawn into and clogging the microchannels during subsequent brazing, it is necessary to pre-fill the microchannels with ceramic-based flow barrier 600 (main components: alumina powder + organic binder).

[0133] (4) Process method: The ceramic-based flow barrier 600 is injected into the first cooling channel 310 and the second cooling channel 320 by slurry injection method, and then dried and cured at 150°C.

[0134] (5) Assembly and brazing: Place a nickel-based brazing filler strip (such as BNi-2) between the back plate 400 and the bottom of the honeycomb structure, and spray powdered brazing filler into the gaps of the honeycomb nodes. Finally, place it in a vacuum brazing furnace and hold it at 1050℃ for 30 minutes to complete the overall metallurgical connection.

[0135] (6) Channel clearing: After brazing, the ceramic barrier powder in the microchannel is completely broken up and discharged by chemical etching (using a solvent for ceramic-based barrier agent 600 binder) combined with ultrasonic cleaning, so as to restore the channel to unobstructed.

[0136] (6) Final processing: Grind the top of the honeycomb to the designed height. Use high-pressure water jet to flush the microchannels at a pressure of 5MPa-10MPa to ensure that no residue blocks the air film pores.

[0137] The honeycomb structure obtained through the above process was simulated and verified. The computational fluid dynamics simulation based on the above parameters shows that:

[0138] Cooling effect: Under the conditions of mainstream gas temperature of 1300℃ and cooling gas volume of 1.5%, the temperature of the metal at the top of the honeycomb structure was reduced from 1150℃ in the traditional structure to 1070℃, successfully avoiding the rapid oxidation range of the material.

[0139] Flow resistance characteristics: Compared with smooth straight-walled honeycomb, the flow coefficient of the structure in this embodiment is reduced by about 22% when the blade tip gap is 0.5mm, which means that the leakage is significantly reduced under the same gap.

[0140] Structural strength: The double-walled structure at the node, combined with the tubular structure of the microchannel, increases the radial compressive strength of the honeycomb by about 15% compared to the traditional single-layer node, making it more resistant to blade tip scraping impact.

[0141] In summary, the honeycomb structure provided by the embodiments of the present invention has the following technical effects:

[0142] (1) Breaking through manufacturing bottlenecks and achieving complex internal cooling at extremely low cost: The invention cleverly utilizes the "node overlapping" process, which is essential in honeycomb manufacturing. Through simple improvements to the stamping die, the originally solid welding nodes are transformed into hollow cooling channels. This completely avoids the high-risk and high-cost deep hole processing (EDM / laser) on a 0.1mm thin wall, making the manufacturing cost of high-performance cooled honeycomb similar to that of ordinary honeycomb.

[0143] (2) Dual cooling mechanism, significantly improving temperature resistance limit: This invention creates a "microvascular" type internal cooling channel, realizing dual cooling through forced convection within the wall and top air film coverage. Thermal analysis shows that, with the same amount of cooling air consumption, this invention can reduce the maximum metal temperature of the honeycomb by 50°C to 80°C, significantly extending the service life of the components in high-pressure turbine environments.

[0144] (3) Active drag enhancement significantly improves sealing efficiency: The aerodynamic drag enhancement feature on the free section 220 transforms the smooth "pipe flow" into a "rough pipe flow" with high turbulence. Simulation studies predict that under typical tip clearance, this structure can increase the effective flow resistance by 15% to 25%, thereby directly reducing gas leakage and improving engine-level efficiency.

[0145] (4) Good structural integrity and no risk of stress concentration: Compared with the later drilling, which is prone to microcracks at the edge of the hole, the microchannel of the present invention is integrally stamped with the metal strip, the inner wall of the flow channel is smooth and rounded, there is no recast layer, and the fatigue resistance is better.

[0146] It should be noted that the term "comprising" and its variations used in the embodiments of this invention are open-ended, meaning "including but not limited to". The term "based on" means "at least partially based on". The term "one embodiment" means "at least one embodiment"; the term "another embodiment" means "at least one additional embodiment"; the term "some embodiments" means "at least some embodiments". The modifications of "one" and "a plurality" mentioned in the embodiments of this invention are illustrative and not restrictive, and those skilled in the art should understand that unless explicitly indicated otherwise in the context, they should be understood as "one or more".

[0147] The steps described in the method embodiments provided by the present invention can be performed in different orders and / or in parallel. Furthermore, the method embodiments may include additional steps and / or omit the steps shown. The scope of protection of the present invention is not limited in this respect.

[0148] The term "embodiment" in this specification refers to a specific feature, structure, or characteristic described in connection with an embodiment that may be included in at least one embodiment of the invention. The appearance of this phrase in various places throughout the specification does not necessarily imply the same embodiment, nor does it imply independence or alternativeity from other embodiments. The various embodiments in this specification are described in a related manner, with reference to each other for similar or identical parts. In particular, for apparatus, device, and system embodiments, since they are substantially similar to method embodiments, the description is relatively simple, and relevant details are referred to in the description of the method embodiments.

[0149] The above-described embodiments are merely illustrative of several implementations of the present invention, and while the descriptions are specific and detailed, they should not be construed as limiting the scope of protection. It should be noted that those skilled in the art can make various modifications and improvements without departing from the inventive concept of the present invention, and these modifications and improvements all fall within the scope of protection of the present invention. Therefore, the scope of protection of the present invention should be determined by the appended claims.

Claims

1. A welded, internally cooled, pneumatically sealed honeycomb structure, characterized in that, include: Multiple interconnected cell units (100); each cell unit (100) includes two integrally formed welded units (200); each welded unit (200) includes: a node segment (210), and free segments (220) symmetrically arranged at both ends of the node segment (210) along a first direction. The free segment (220) is disposed on the same side of the node segment (210); the extension direction of the free segment (220) and the first angle between the node segment (210) are between 60° and 150°. A first groove (211) is provided on the surface of the first end of the node segment (210) away from the free segment (220); the first end is the end of the free segment (220) away from the node segment (210); the first groove (211) penetrates the node segment (210) along a second direction; the second direction is perpendicular to the first direction; the two welding units (200) in the honeycomb unit (100) are mirror-symmetrical along the first direction, and the first ends of the two welding units (200) are welded to each other; the node segments (210) of the two honeycomb units (100) that are mirror-symmetrical along the first direction are welded to each other, and the two first grooves (211) of the two welded node segments (210) are spliced ​​to form a first cooling channel (310).

2. The internally cooled pneumatically sealed honeycomb structure based on welding according to claim 1, characterized in that, The welding unit (200) further includes: a welding section (230); The welded section (230) is symmetrically arranged on both sides of the two free sections (220) along the first direction; the welded section (230) is half of the node section (210), including a straight section (231) and a grooved section (232); one end of the straight section (231) is connected to the first end, and the other end is connected to the grooved section (232); the grooved section (232) and the free section (220) are located on the same side of the welded section (230); In each of the cellular units (100), two of the welded segments (230) that are mirror-symmetrical along the first direction are welded together, and the two groove segments (232) of the two welded segments (230) are spliced ​​together to form the second groove of the cellular unit (100); the two second grooves of the two cellular units (100) that are mirror-symmetrical along the third direction are welded together, and a second cooling channel (320) is formed between the two welded second grooves; the third direction is perpendicular to the first direction and the second direction.

3. The internally cooled pneumatically sealed honeycomb structure based on welding according to claim 1, characterized in that, The wall of the free section (220) is provided with at least one aerodynamic drag-increasing structure (221). The aerodynamic drag-increasing structure (221) includes any one or more combinations of guide ribs, vortex generator protrusions, and discontinuous dimples; the second included angle between the extension direction of the aerodynamic drag-increasing structure (221) and the length direction of the free segment (220) is between 10 degrees and 45 degrees.

4. The internally cooled pneumatically sealed honeycomb structure based on welding according to claim 1, characterized in that, The cross-sectional shape of the cooling channel is circular, elliptical, or rhomboid.

5. The internally cooled pneumatically sealed honeycomb structure based on welding according to claim 4, characterized in that, The first cooling channel (310) has a circular cross-sectional shape; the thickness of each segment of the welding unit (200) is the same, which is t; The ratio of the hydraulic diameter Dh to the thickness t of the first cooling channel (310) satisfies: 3≤Dh / t≤8.

6. The internally cooled pneumatically sealed honeycomb structure based on welding according to claim 1, characterized in that, The honeycomb structure also includes a back plate (400). The back plate (400) is connected to one end of each of the honeycomb cells (100) in the second direction, and the back plate (400) is provided with an air inlet (410) connected to each of the cooling channels for supplying cooling air to the honeycomb structure.

7. The internally cooled pneumatically sealed honeycomb structure based on welding according to claim 1, characterized in that, The two node segments (210) that are welded together are connected by brazing, and brazing material is filled between the connecting parts of the two node segments (210).

8. A processing method for an internally cooled pneumatically sealed honeycomb structure based on welding, characterized in that, Includes the following steps: Multiple integrally formed welding units (200) are stamped from a metal plate; wherein, the welding unit (200) includes: a node segment (210), and free segments (220) symmetrically arranged at both ends of the node segment (210) along a first direction; the free segments (220) are arranged on the same side of the node segment (210); the extension direction of the free segment (220) and the first angle between the node segment (210) and the node segment (210) are between 60° and 150°; a first groove (211) is provided on the surface of the node segment (210) away from the first end of the free segment (220); the first end is the end of the free segment (220) away from the node segment (210); the first groove (211) penetrates the node segment (210) along a second direction; the second direction is perpendicular to the first direction; Any two of the welding units (200) are arranged symmetrically in the first direction and assembled into a honeycomb unit (100), resulting in a plurality of the honeycomb units (100). The individual honeycomb cells (100) are assembled to form a honeycomb structure with cooling channels, and each cooling channel is filled with a ceramic-based flow barrier; wherein, the cooling channel includes a first cooling channel (310); the first cooling channel (310) is obtained by assembling the first groove (211) of two honeycomb cells (100) that are mirror-symmetrical along the first direction; After the ceramic-based flow barrier is dried and cured, the connection nodes of adjacent honeycomb units (100) are welded together. After welding is completed, the ceramic-based flow barrier in the cooling channel is removed to obtain the final honeycomb structure.

9. The processing method for the internally cooled pneumatically sealed honeycomb structure based on welding according to claim 8, characterized in that, Arrange any two of the welding units (200) in a mirror-symmetrical manner along the first direction to form a honeycomb unit (100), including the following steps: Any two of the welding units (200) are arranged symmetrically in a mirror image along the first direction; Two mirror-symmetrical welded segments (230) in the two welding units (200) along the first direction are joined together, so that the groove segments (232) of the two welded segments (230) form a second groove, resulting in a honeycomb unit (100); wherein, the welded segments (230) are symmetrically arranged on both sides of the node segment (210) along the first direction; the welded segment (230) is 1 / 2 of the node segment (210), including a straight segment (231) and the groove segment (232); one end of the straight segment (231) is connected to the first end, and the other end of the straight segment (231) is connected to the groove segment (232); the groove segment (232) and the free segment (220) are located on the same side of the welded segment (230).

10. The processing method for the internally cooled pneumatically sealed honeycomb structure based on welding according to claim 9, characterized in that, Assembling the individual cellular cells (100) to form a cellular structure with cooling channels includes the following steps: Any two of the honeycomb cells (100) are arranged symmetrically in the first direction, and the two first grooves (211) of the two honeycomb cells (100) are joined together to form a first cooling channel (310). Any two of the cellular units (100) are arranged in a mirror-symmetrical manner along a third direction, and the two second grooves of the two cellular units (100) are joined together to form a second cooling channel (320), thereby obtaining a cellular structure having the first cooling channel (310) and the second cooling channel (320).

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