Louver type laminate cooling structure and using method

Abstract

The invention discloses a shutter type laminate cooling structure and a using method, the shutter type laminate cooling structure mainly comprises an inner layer wall, connecting ribs and an outer layer wall, the inner layer wall is provided with impact grooves, the connecting ribs form a rectangular impact cavity, and the outer layer wall is provided with air film grooves. Cooling air enters the impact cavity from the impact groove, completes impact cooling on the inner wall face of the outer layer wall and then flows out from the air film groove in the outer layer wall, and an air film is formed to protect the outer layer wall. The space between the laminates is divided into the relatively closed impact cavities, and the air inlet channel and the air outlet channel are designed to be of a shutter type parallel slot structure, so that the internal cooling area is greatly increased, transverse flow interference and cold air retention between new cold air and old cold air are avoided, the flow resistance is reduced, the cold air cooling potential is fully explored, and the service life of the cold air cooler is prolonged. And the laminated plate cooling effect is remarkably improved, and good application prospects are achieved.

Description

Technical Field

[0001] The invention belongs to the technical field of gas turbine cooling, and in particular relates to a louvered layer plate cooling structure and a use method thereof. Background Art

[0002] A heavy-duty gas turbine is a rotary impeller power machine that uses a continuously flowing gas as a working fluid to drive the impeller to rotate at high speed, converting the energy of the fuel into useful work. Its working principle mainly includes the following steps: Compression process: The compressor inhales air from the external atmospheric environment, and compresses it step by step through the axial flow compressor to increase the pressure, and the air temperature is also increased accordingly. Combustion process: The compressed air is pressed into the combustion chamber and mixed with the injected fuel to burn, generating high-temperature and high-pressure gas. Working process: The high-temperature and high-pressure gas enters the turbine to expand and work, driving the turbine to drive the compressor and the external load rotor to rotate at high speed, realizing the partial conversion of the chemical energy of the gas or liquid fuel into mechanical work, and outputting electrical work. The design, manufacture and testing of heavy-duty gas turbines are extremely difficult, involving multi-physical field coupling and multi-disciplinary technology integration. Its key components such as compressors, combustion chambers, high-temperature turbine blades, etc. need to operate stably for a long time under high temperature, high stress, and high corrosion environments, which puts extremely high demands on materials, processes and design levels.

[0003] Heavy-duty gas turbines are high-end equipment in the field of power generation equipment, with fast adjustment speed, high operating efficiency and high operating temperature. At present, the turbine inlet temperature of mainstream heavy-duty gas turbines has exceeded the melting point of the blade matrix material, and an efficient and precise cooling structure must be arranged to achieve the design goal of reducing blade temperature and extending blade life.

[0004] Laminated plate cooling is a cooling structure arranged in the hot end parts such as the combustion chamber, turbine end wall, and turbine blade of a gas turbine. It is mainly divided into two layers of inner and outer walls. The inner wall is arranged with impact holes, and the outer wall is arranged with air film holes. The two walls are connected by spoiler columns. In the process of cooling through the impact holes, spoiler columns, and air film holes, the impingement cooling, forced convection heat exchange, and air film cooling are completed, achieving efficient cooling of the laminate.

[0005] However, the existing plate cooling technology is designed based on current precision casting methods. The impact holes, spoiler columns, and air film holes are all large-sized (relative to the wall thickness) simple cylindrical structures. The flow of cold air in the plate is disordered and disordered, and the new and old cold air are mixed with each other. The uniformity of cold air distribution is poor and the flow resistance is large, resulting in low cold air utilization. With the development of metal 3D printing technology, the design of turbine blade plate cooling can also explore more ingenious structures to avoid cross-flow interference and tap the heat exchange potential of cooling air. Summary of the invention

[0006] The invention provides a louvered layer plate cooling structure and a use method thereof, aiming to overcome the shortcomings of the existing layer plate cooling structure.

[0007] In order to achieve the above object, the present invention adopts the following technical solution: The present invention provides a louver-type layer plate cooling structure, which is integrally formed using 3D printing technology and includes an inner wall, an outer wall and connecting ribs. The inner wall and the outer wall are connected together by connecting ribs to form an impact cavity. A plurality of impact grooves connected to the impact cavity are provided on the inner wall, and a plurality of air film grooves connected to the impact cavity are provided on the outer wall.

[0008] A further improvement of the present invention is that the cross-sectional shape of the impact cavity includes a polygon and a chamfered polygon; the side length L of the impact cavity is c The value range is 5~100mm.

[0009] A further improvement of the present invention is that the connecting rib thickness T r The value range is 0.5~10mm.

[0010] A further improvement of the present invention is that the angle α between the air film groove and the horizontal plane ranges from 5° to 90°.

[0011] A further improvement of the present invention is that the impact groove thickness T imp The value range is 0.1~10mm.

[0012] A further improvement of the present invention is that the distance L between the side impact groove and the connecting rib is imp The value range is 0.1~10mm.

[0013] A further improvement of the present invention is that the thickness of the air film groove T f The value range is 0.1~10mm.

[0014] A further improvement of the present invention is that the inner wall thickness T i The value range is 0.1~10mm; Impact chamber height T c The value range is 0.1~10mm; Outer wall thickness T o The value range is 0.1~10mm; The total thickness of the layer cooling structure is T w The value range is 0.1~50mm.

[0015] A further improvement of the present invention is that the pitch P of the air film grooves is f The value range is 1~50mm; Impact groove pitch P i The value range is 1~50mm.

[0016] The present invention also provides a method for using the louvered layer plate cooling structure. The method is based on the louvered layer plate cooling structure and comprises: The cooling air enters the impact cavity through the impact groove, and after completing the impact cooling on the inner wall surface of the outer wall, it flows out through the air film groove on the outer wall, forming an air film to protect the outer wall.

[0017] Compared with the prior art, the present invention has at least the following beneficial technical effects: The present invention provides a louvered plate cooling structure and a method of using the structure. By arranging closed connecting ribs and louvered impact grooves and air film groove structures inside the turbine blade plate structure, the impact cavity space is isolated, the cooling air jets are isolated from each other, and the mutual interference between the new and old cooling air is avoided. The louvered parallel slot structure has the characteristics of large cooling area and good cold air expansion effect, and can evenly spread the cold air. Although the cooling intensity is lower than the impact cold air, the total heat exchange, cooling uniformity, and air film uniformity are significantly better than the existing technology. At the same time, due to the uniform flow and the avoidance of the arrangement of spoiler columns, the cooling flow resistance is greatly reduced. According to calculations, the effective cooling area of ​​the present invention is increased by 65%, the internal cooling heat exchange is increased by 16%, the comprehensive cooling efficiency is increased by 59%, and the total pressure loss coefficient is reduced by 44%. It can significantly enhance the cooling effect and cooling air utilization rate of the turbine blade plate cooling structure, and has good application prospects. BRIEF DESCRIPTION OF THE DRAWINGS

[0018] In order to more clearly illustrate the specific implementation methods of the present invention or the technical solutions in the prior art, the drawings required for use in the specific implementation methods or the description of the prior art will be briefly introduced below. Obviously, the drawings described below are some implementation methods of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative work.

[0019] Figure 1 It is a three-dimensional stereogram of the present invention.

[0020] Figure 2 A diagram of a prior art structure for cooling a laminate.

[0021] Figure 3 (a)-(c) are top views and AA and BB cross-sectional views of the present invention.

[0022] Figure 4 is a comparison chart of the comprehensive cooling efficiency between the prior art and this embodiment, wherein Figure 4 (a) is prior art, Figure 4 (b) is an embodiment of the present invention.

[0023] Explanation of the accompanying drawings: 1. inner wall; 2. outer wall; 3. connecting rib; 4. impact groove; 5. air film groove; 6. spoiler column; 7. impact hole; 8. air film hole. DETAILED DESCRIPTION

[0024] In the following, only some exemplary embodiments are briefly described. As those skilled in the art will appreciate, the described embodiments may be modified in various ways without departing from the spirit or scope of the present invention. Therefore, the drawings and descriptions are considered to be exemplary and non-restrictive in nature.

[0025] In the description of the present invention, it should be understood that the terms "center", "longitudinal", "lateral", "length", "width", "thickness", "up", "down", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inside", "outside", "clockwise", "counterclockwise", "axial", "radial", "circumferential" and the like indicate orientations or positional relationships based on the orientations or positional relationships shown in the accompanying drawings, and are only for the convenience of describing the present invention and simplifying the description, and do not indicate or imply that the referred device or element must have a specific orientation, be constructed and operated in a specific orientation, and therefore should not be understood as limiting the present invention.

[0026] In addition, the terms "first" and "second" are used for descriptive purposes only and should not be understood as indicating or implying relative importance or implicitly indicating the number of the indicated technical features. Therefore, the features defined as "first" and "second" may explicitly or implicitly include one or more of the features. In the description of the present invention, the meaning of "plurality" is two or more, unless otherwise clearly and specifically defined.

[0027] In the present invention, unless otherwise clearly specified and limited, the terms "installed", "connected", "connected", "fixed" and the like should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection, an electrical connection, or a communication; it can be a direct connection, or an indirect connection through an intermediate medium, it can be the internal connection of two elements or the interaction relationship between two elements. For ordinary technicians in this field, the specific meanings of the above terms in the present invention can be understood according to specific circumstances.

[0028] In the present invention, unless otherwise clearly specified and limited, a first feature being "above" or "below" a second feature may include that the first and second features are in direct contact, or may include that the first and second features are not in direct contact but are in contact through another feature between them. Moreover, a first feature being "above", "above" and "above" a second feature includes that the first feature is directly above and obliquely above the second feature, or simply indicates that the first feature is higher in level than the second feature. A first feature being "below", "below" and "below" a second feature includes that the first feature is directly above and obliquely above the second feature, or simply indicates that the first feature is lower in level than the second feature.

[0029] It should also be understood that the terms used in the present specification are only for the purpose of describing specific embodiments and are not intended to limit the present invention. As used in the present specification and the appended claims, unless the context clearly indicates otherwise, the singular forms "a", "an" and "the" are intended to include plural forms.

[0030] It should be further understood that the term "and / or" used in the present description and the appended claims refers to any and all possible combinations of one or more of the associated listed items, and includes these combinations.

[0031] Various structural schematic diagrams of the embodiments disclosed in the present invention are shown in the accompanying drawings. These figures are not drawn to scale, and some details are magnified and some details may be omitted for the purpose of clear expression. The shapes of various regions and layers shown in the figures and the relative sizes and positional relationships therebetween are only exemplary, and may deviate in practice due to manufacturing tolerances or technical limitations, and those skilled in the art may additionally design regions / layers with different shapes, sizes, and relative positions according to actual needs.

[0032] The embodiments of the present invention are described in detail below with reference to the accompanying drawings.

[0033] Example 1 like Figure 1 As shown, a louvered layer plate cooling structure provided in this embodiment is integrally formed by 3D printing technology, and includes an inner wall 1, an outer wall 2, a connecting rib 3, an impact groove 4, and an air film groove 5. The inner wall 1 and the outer wall 2 are connected together by the connecting rib 3 to form an impact cavity, and a plurality of impact grooves 4 connected to the impact cavity are provided on the inner wall 1, and a plurality of air film grooves 5 connected to the impact cavity are provided on the outer wall 2.

[0034] Among them, the design of the impact groove allows the cooling medium (such as air or water) to directly impact the inner wall, forming a strong convection heat exchange, which effectively improves the heat exchange efficiency. The air film groove helps to form a thin layer of air film on the surface of the outer wall. This air film not only reduces the heat exchange between the outer wall and the external environment, but also further enhances the cooling effect, because the air film itself also has a certain insulation and cooling effect. The connecting ribs firmly connect the inner wall and the outer wall together to form a stable overall structure, which improves the deformation resistance and load-bearing capacity of the layer. The one-piece molding characteristics of 3D printing technology ensure seamless connection between the components, avoid gaps and weaknesses that may be caused by traditional assembly methods, and further enhance the overall strength of the structure.

[0035] The arrangement and size of the impact grooves and the air film grooves can be optimized according to specific cooling requirements to achieve a more uniform flow field distribution and a more efficient cooling effect. This customized design capability enables the present invention to adapt to different shapes and sizes of layers, as well as different cooling media and working conditions.

[0036] 3D printing technology allows the use of lightweight materials and can further reduce weight by optimizing structural design, which is of great significance for fields such as aviation and aerospace that need to reduce deadweight. The one-piece design reduces multiple steps in the traditional manufacturing process, such as mold making and component assembly, greatly simplifies the manufacturing process and reduces production costs. The rapid prototyping capability of 3D printing technology also makes the production cycle of the present invention shorter, making it easier to achieve rapid iteration and customized production.

[0037] In this embodiment, the cross-sectional shape of the impact cavity includes but is not limited to a polygon and a rounded polygon, and in this embodiment, a square is preferably used. The square cross-sectional shape has four equal sides, which makes the cooling air more uniform when flowing in the impact cavity. Uniform fluid flow helps to ensure that all parts of the inner wall surface can be fully cooled and improve the cooling efficiency. The square is a very stable geometric shape with good structural rigidity and strength. In a high temperature and high pressure working environment, the square cross-sectional shape can withstand large stress and deformation, ensuring the stability and reliability of the cooling structure. The square cross-sectional shape is relatively simple and easy to be manufactured in one piece using 3D printing technology. The precision and flexibility of 3D printing technology make the realization of the square cross-sectional shape easier, while reducing the processing cost and manufacturing difficulty. The square cross-sectional shape provides more optimization space for the design of the impact cavity. For example, the fluid dynamics performance and thermal conductivity performance of the cooling structure can be optimized by adjusting the parameters such as the side length of the square, the position and size of the impact groove and the air film groove. The square cross-sectional shape has good adaptability and versatility, and can be applied to louvered layer cooling structures of different sizes and specifications. This versatility makes the square cross-sectional shape more flexible in the design and manufacturing process, and can meet the needs of different application scenarios.

[0038] In this embodiment, the side length L of the impact chamber c The value range is 5~100mm, and 22mm is preferred in this embodiment.

[0039] In this embodiment, the connecting rib thickness T r The value range is 0.5~10mm, and 2mm is preferred in this embodiment.

[0040] In this embodiment, the angle α between the air film groove and the horizontal plane ranges from 5° to 90°, and is preferably 30° in this embodiment.

[0041] In this embodiment, the impact groove thickness T imp The value range is 0.1~10mm, and the preferred value in this embodiment is 0.8mm.

[0042] In this embodiment, the distance L between the side impact groove and the connecting rib is imp The value range is 0.1~10mm, and the preferred value in this embodiment is 2.6mm.

[0043] In this embodiment, the thickness of the air film groove is T f The value range is 0.1~10mm, and 0.4mm is preferred in this embodiment.

[0044] In this embodiment, the inner wall thickness T i The value range is 0.1~10mm, and 4mm is preferred in this embodiment.

[0045] In this embodiment, the impact chamber height T c The value range is 0.1~10mm, and 4mm is preferred in this embodiment.

[0046] In this embodiment, the outer wall thickness T o The value range is 0.1~10mm, and 3mm is preferred in this embodiment.

[0047] In this embodiment, the total thickness of the laminate structure is T w The value range is 0.1~50mm, and 11mm is preferred in this embodiment.

[0048] In this embodiment, the pitch P of the air film grooves of the louvered layer cooling structure is f The value range is 1~50mm, and the preferred value in this embodiment is 7.2mm.

[0049] In this embodiment, the pitch of the impact grooves of the louvered plate cooling structure is i The value range is 1~50mm, and the preferred value in this embodiment is 7.2mm.

[0050] Example 2 The present invention provides a method for using a louvered layer plate cooling structure, which is based on a louvered layer plate cooling structure, which is integrally formed using 3D printing technology and includes an inner wall 1, an outer wall 2, a connecting rib 3, an impact groove 4, and an air film groove 5. The inner wall 1 and the outer wall 2 are connected together by the connecting rib 3 to form an impact cavity, and the inner wall 1 is provided with a plurality of impact grooves 4 connected to the impact cavity, and the outer wall 2 is provided with a plurality of air film grooves 5 connected to the impact cavity; the method includes: cooling air enters the impact cavity from the impact groove, and after the impact cooling is completed on the inner wall surface of the outer wall, the cooling air flows out through the air film groove on the outer wall to form an air film to protect the outer wall.

[0051] The present invention introduces cooling air directly into the impact cavity through the impact groove, so that the cooling air can use the inner wall as the impact surface, forming a strong impact cooling effect. This cooling method can quickly reduce the temperature of the inner wall, and then reduce the temperature of the entire layer plate through heat conduction.

[0052] After the cooling air has completed the impact cooling, it flows out through the air film grooves on the outer wall, forming a thin air film covering the outer wall surface. This air film not only plays a role in heat insulation, but also prevents the external hot air from directly contacting the outer wall, further improving the cooling efficiency.

[0053] The use of 3D printing technology for one-piece molding makes the entire layer cooling structure an integral whole, avoiding the gaps and leakage problems that may occur in the traditional assembly process, and improving the sealing and reliability of the structure. 3D printing technology also allows complex geometric shapes and internal structures to be implemented in the design, which may be difficult to achieve in traditional manufacturing methods. At the same time, by optimizing the structural design, the weight can be reduced while ensuring strength, achieving lightweight.

[0054] The design of the air film slot allows the cooling air to form a uniform air film when it flows out. This air film acts as a thermal barrier, effectively preventing the heat conduction and heat radiation of the external high temperature environment to the laminate, and enhancing the thermal protection performance of the laminate. In a high temperature environment, this air film protection mechanism can significantly extend the service life of the laminate and improve the stability and reliability of the system.

[0055] The use of 3D printing technology makes the manufacturing of the layer cooling structure more flexible and can be customized according to specific application requirements. Whether it is the position and size of the impact groove, or the shape and distribution of the air film groove, it can be adjusted and optimized according to actual needs. This customizability enables the layer cooling structure to better adapt to different working environments and cooling requirements, improving its applicability and practicality.

[0056] Since the layer plate cooling structure adopts an integrated design, the connection and assembly between components are reduced, so it is easier and faster to maintain and replace. If the layer plate is damaged or needs to be replaced, the entire layer plate cooling structure can be replaced directly without disassembling and replacing each component one by one, which greatly saves time and labor costs.

[0057] Comparative Example 1 use Figure 2 The prior art structure of the plate cooling shown in the figure is used as a comparison to perform numerical simulation on this embodiment, where 6 is a spoiler column, 7 is an impact hole, and 8 is an air film hole. The target surface comprehensive cooling efficiency and total pressure loss coefficient under the condition of the plate cooling blowing ratio of 1.0 (same flow conditions) are calculated. The blowing ratio is a dimensionless parameter used to measure the air film outflow state of the air film hole, and its definition is as follows: (1) Where: ρ is the fluid density, in kg·m3; u is the fluid velocity, in m / s; subscript f indicates the inlet position of the air film hole; subscript ∞ indicates the incoming flow position.

[0058] The comprehensive cooling efficiency is a dimensionless parameter used to measure the overall cooling performance of the internal and external cooling structures. Its definition is as follows: (2) in: is the total temperature of the mainstream inlet, in K; is the outer surface temperature of the wall, in K; is the total temperature of the cooling air inlet, in K.

[0059] The total pressure loss coefficient is a dimensionless parameter used to evaluate the flow loss of the cooling structure. Its definition is as follows: (3) in: is the mainstream flow rate, in kg / s; is the cooling air flow rate, in kg / s; is the total pressure of the outlet gas, in Pa; is the total pressure of the mainstream inlet, in Pa; It is the total pressure at the cooling air inlet, in Pa.

[0060] Comparison results of comprehensive cooling effect Figure 4 As shown. It can be seen that the comprehensive cooling efficiency of this embodiment is significantly improved compared with the prior art, and the spanwise coverage area and coverage uniformity of the cold air ejected from the louvered air film slots are significantly better than those of the prior art. According to calculations, compared with the prior art, the effective cooling area of ​​this embodiment is increased by 65%, the internal cooling heat exchange is increased by 16%, the comprehensive cooling efficiency is increased by 59%, and the total pressure loss coefficient is reduced by 44%, which can meet the needs of more efficient layer plate cooling technology.

[0061] The above shows and describes the basic principles and main features of the present invention and the advantages of the present invention. It is obvious to those skilled in the art that the present invention is not limited to the details of the above exemplary embodiments, and the present invention can be implemented in other specific forms without departing from the spirit or basic features of the present invention. Therefore, no matter from which point of view, the embodiments should be regarded as exemplary and non-restrictive. The scope of the present invention is defined by the attached claims rather than the above description, and it is intended that all changes falling within the meaning and scope of the equivalent elements of the claims are included in the present invention. Any figure mark in the claims should not be regarded as limiting the claims involved.

[0062] In addition, it should be understood that although this specification is described in accordance with the implementation modes, not every implementation mode contains only one independent technical solution. This description of the specification is only for the sake of clarity. Those skilled in the art should regard the specification as a whole. The technical solutions in each embodiment can also be appropriately combined to form other implementation modes that can be understood by those skilled in the art. The above content is only to illustrate the technical idea of ​​the present invention, and cannot be used to limit the protection scope of the present invention. Any changes made on the basis of the technical solution according to the technical idea proposed by the present invention shall fall within the protection scope of the claims of the present invention.

Claims

1. A louvered layer plate cooling structure, characterized in that: The structure is integrally formed using 3D printing technology, and includes an inner wall, an outer wall and connecting ribs. The inner wall and the outer wall are connected together by connecting ribs to form an impact cavity. The inner wall is provided with a number of impact grooves connected to the impact cavity, and the outer wall is provided with a number of air film grooves connected to the impact cavity.

2. A louvered layer plate cooling structure according to claim 1, characterized in that: The cross-sectional shape of the impact cavity includes polygon and rounded polygon; the side length of the impact cavity is L c The value range is 5~100mm.

3. The louvered layer plate cooling structure according to claim 1, characterized in that: Connecting rib thickness T r The value range is 0.5~10mm.

4. The louvered layer plate cooling structure according to claim 1, characterized in that: The angle α between the air film groove and the horizontal plane ranges from 5° to 90°.

5. The louvered layer plate cooling structure according to claim 1, characterized in that: Impact groove thickness T imp The value range is 0.1~10mm.

6. The louvered layer plate cooling structure according to claim 1, characterized in that: Distance between side impact groove and connecting rib L imp The value range is 0.1~10mm.

7. The louvered layer plate cooling structure according to claim 1, characterized in that: Air film groove thickness T f The value range is 0.1~10mm.

8. The louvered layer plate cooling structure according to claim 1, characterized in that: Inner wall thickness T i The value range is 0.1~10mm; Impact cavity height T c The value range is 0.1~10mm; Outer wall thickness T o The value range is 0.1~10mm; The total thickness of the layer cooling structure is T w The value range is 0.1~50mm.

9. The louvered layer plate cooling structure according to claim 1, characterized in that: Air film groove pitch P f The value range is 1~50mm; Impact groove pitch P i The value range is 1~50mm.

10. A method for using a louvered layer cooling structure, characterized in that: The method is based on a louvered layer plate cooling structure according to any one of claims 1 to 9, comprising: The cooling air enters the impact cavity through the impact groove, and after completing the impact cooling on the inner wall surface of the outer wall, it flows out through the air film groove on the outer wall, forming an air film to protect the outer wall.

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