High-load diffusion cascade with local bionic fish scale structure and design method of high-load diffusion cascade

Abstract

The invention provides a high-load diffusion cascade with a local bionic fish scale structure and a design method thereof, the bionic fish scale structure is arranged on the high-load diffusion cascade, and the bionic fish scale structure locally exists on the high-load diffusion cascade; the bionic fish scale structure is formed by arranging a plurality of micro fish scale structures in an array mode. The thickness of a boundary layer can be effectively adjusted, local flow resistance is reduced, pneumatic loss is reduced, and therefore the overall working efficiency of the cascade is improved; and particularly, under the high-load working condition, the bionic fish scale structure can remarkably improve the flow stability and restrain generation and expansion of flow separation, efficient operation of the cascade under the high-load condition is ensured, and the aerodynamic performance and stability of the gas compressor are further enhanced.

Description

Technical Field

[0001] This invention relates to the field of turbomachinery technology, and more particularly to a high-load diffuser blade cascade with a localized biomimetic fish-scale structure and its design method. Background Technology

[0002] Flow control technologies, based on energy input mechanisms, can be divided into two categories: active control and passive control. Active control technologies, such as plasma excitation and boundary layer pumping, achieve precise flow field control by introducing external energy. While they offer strong dynamic response and adaptability to varying operating conditions, they rely on complex additional energy supply devices and control systems, leading to high integration costs and limited reliability in practical applications. In contrast, passive control technologies, including swept blade configurations, tip winglets, and vortex generators, reconstruct flow modes through geometric innovation rather than external energy input. Their passive nature and high compatibility with existing manufacturing processes make them significantly advantageous in achieving engineering goals such as suppressing flow separation and attenuating secondary flow losses. Passive flow control technologies with simple structures hold great application potential for addressing the complex three-dimensional flow characteristics within high-load diffuser cascade channels. Summary of the Invention

[0003] To address the aforementioned technical problems, a high-load diffuser cascade with a localized biomimetic fish-scale structure and its design method are provided.

[0004] The technical means employed in this invention are as follows: A high-load diffuser cascade with a localized biomimetic fish scale structure, wherein the high-load diffuser cascade is provided with a biomimetic fish scale structure, and the biomimetic fish scale structure is locally present on the high-load diffuser cascade; the biomimetic fish scale structure is composed of an array of several micro fish scale structures.

[0005] Furthermore, the bottom of the micro-fish scale structure is a plane, the micro-fish scale structure has a certain thickness and a fan-shaped cross-section, and the two sides of the micro-fish scale structure are a first arc surface and a second arc surface, respectively, the radius of the first arc surface is smaller than the radius of the second arc surface.

[0006] Furthermore, the micro-fish scale structure is in the form of a groove structure or a protruding structure.

[0007] Furthermore, the arrangement of the biomimetic fish scale structure is either parallel or staggered, and the arrangement parameter is the fish scale spacing.

[0008] Furthermore, the high-load diffuser cascade is a planar cascade structure or an annular cascade structure, wherein the planar cascade structure is partially provided with a biomimetic fish scale structure, and the annular cascade structure is partially provided with a biomimetic fish scale structure.

[0009] Furthermore, the planar blade cascade structure includes a diffuser cascade plate and blades, the blades being fixedly connected to the diffuser cascade plate, and the biomimetic fish scale structure being partially present on the blades and / or the diffuser cascade plate. The biomimetic fish scale structure is arranged separately on the suction surface of the blade; or, the biomimetic fish scale structure is arranged separately at the leading edge of the diffuser cascade plate; or, the biomimetic fish scale structure is arranged separately on the side wall of the suction surface of the diffuser cascade plate; or, the biomimetic fish scale structure is arranged simultaneously on both the suction surface of the blade and the leading edge of the diffuser cascade plate; or, the biomimetic fish scale structure is arranged simultaneously on both the suction surface of the blade and the side wall of the suction surface of the diffuser cascade plate; or, the biomimetic fish scale structure is arranged simultaneously on both the leading edge of the diffuser cascade plate and the side wall of the suction surface of the diffuser cascade plate; or, the biomimetic fish scale structure is arranged simultaneously on the leading edge of the diffuser cascade plate, the side wall of the suction surface of the diffuser cascade plate, and the suction surface of the blade.

[0010] Furthermore, the annular blade cascade structure includes blades, a casing, and a hub. The blades are fixedly connected to blade-shaped grooves provided on the casing and the hub. The biomimetic fish scale structure is partially present on the blades and / or the hub. The biomimetic fish scale structure is arranged separately on the blade's suction surface; or, the biomimetic fish scale structure is arranged separately on the hub of the blade's leading edge; or, the biomimetic fish scale structure is arranged separately on the hub of the blade's suction surface side; or, the biomimetic fish scale structure is arranged simultaneously on the hub of both the blade's suction surface and the blade's leading edge; or, the biomimetic fish scale structure is arranged simultaneously on the blade's suction surface and the hub of the blade's suction surface side; or, the biomimetic fish scale structure is arranged simultaneously on the hub of the blade's suction surface side, the hub of the blade's leading edge, and the hub of the blade's suction surface side.

[0011] This invention also provides a design method for a high-load diffuser cascade with a local biomimetic fish-scale structure, comprising the following steps: S1. Establish a spatial rectangular coordinate system with the center of the biomimetic fish scale structure as the origin o, and define eight points in this spatial rectangular coordinate system to determine the structural parameters of a single micro-fish scale structure. The structural parameters of a single micro-fish scale structure include depth. h ,length s ,width l ; S2. After determining the structural parameters of a single micro-fish scale structure, numerical calculations are performed to determine the spacing between adjacent rows of fish scales and between different rows of fish scales. Combined with the corresponding position parameters, the final arrangement of the biomimetic fish scale structure on the diffuser cascade plate, blades, and hub is determined. Parallel or staggered arrangements are adopted, and the biomimetic fish scale structure profile is formed by array arrangement and combination. The corresponding diffuser cascade plate, blades, and hub structure with biomimetic fish scale structure is further generated.

[0012] Furthermore, in S1, the eight given points are as follows: , , , , , , , ; in, ; ; ; ; ; In the formula, This is the starting point on the upper side of the first arc surface of the micro-fish scale structure. This is the upper end point of the first arc surface of the micro-fish scale structure. This is the starting point on the upper side of the second arc surface of the micro-fish scale structure. This is the upper end point of the second arc surface of the micro-fish scale structure. This is the starting point on the lower side of the first arc surface of the micro-fish scale structure. This is the lower end point of the first arc surface of the micro-fish scale structure. This is the starting point on the lower side of the second arc surface of the micro-fish scale structure. This is the lower end point of the second arc surface of the micro-fish scale structure. The length of the microscale structure, The width of the first arc surface of the micro-fish scale structure. The width of the second arc surface of the micro-fish scale structure. The depth of the micro-fish scale structure; Connect them with straight lines respectively , , , , , , and The first arc surface of the biomimetic fish scale structure , Second arc surface , The curves between these curves can be modeled using methods such as quadratic Bézier curves, cubic Bézier curves, and quadratic B-spline curves. The specific parametric equations are as follows: ; ; ; In the formula, The governing equations for a quadratic Bézier curve are given. The governing equations for cubic Bézier curves are given. , , , As control points for curve shaping, t The parameter has a range of values. ; The governing equations for a quadratic B-spline curve are... It is a quadratic B-spline basis function, and its fundamental condition is when hour, ; Recursive formula for: .

[0013] Furthermore, in S2, the parameters of the biomimetic fish scale structure on the diffuser cascade plate or hub are the same as the dimensions of the biomimetic fish scale structure on the blade, or are determined separately based on the corresponding numerical calculation results.

[0014] Compared with the prior art, the present invention has the following advantages: 1. The present invention provides a high-load diffuser cascade with a localized biomimetic fish-scale structure and its design method. The biomimetic fish-scale structure can stably induce the formation of a low-speed rotating flow structure. This self-flowing structure transforms the sliding friction between the mainstream fluid and the solid wall into rolling friction within the fluid, achieving a function similar to a "miniature fluid bearing." This shift in frictional energy dissipation mode effectively reduces the local resistance of the flow near the micro-fish-scale structure. Furthermore, the arrangement area and form of the micro-fish-scale structure can be flexibly selected according to actual engineering needs. When the micro-fish-scale structure is arranged in an array, its drag reduction effect has a cumulative effect on the regional scale, thereby significantly reducing the flow resistance of the entire array coverage area.

[0015] 2. The high-load diffuser cascade with local biomimetic fish scale structure and its design method provided by the present invention can induce local secondary flow to enhance the momentum transfer of fluid in the near-wall region by arranging the biomimetic fish scale structure on the suction surface of the blade, reduce the boundary layer velocity gradient, thereby delaying flow separation under high adverse pressure gradient, effectively reducing the area of ​​the separation region and reducing flow loss.

[0016] 3. The high-load diffuser cascade with local biomimetic fish scale structure and its design method provided by the present invention, by arranging biomimetic fish scale structure on the end wall of the diffuser cascade plate / hub leading edge and the end wall of the diffuser cascade plate / hub suction side, can regulate the interaction between the horseshoe vortex leading edge branch and the end wall boundary layer. The induced spanwise vortex can effectively disperse the accumulated low-energy fluid, reduce the intensity of the channel vortex and delay its migration to the middle of the flow channel, thereby reducing secondary flow mixing loss and corner separation loss, etc.

[0017] 4. The high-load diffuser cascade with a localized biomimetic fish-scale structure and its design method provided by this invention offer greater flexibility in the arrangement of the biomimetic fish-scale structure. It can be arranged in parallel or staggered configurations, and can be locally arranged according to actual conditions. The localized biomimetic fish-scale structure can control the flow field without relying on external energy input, and its fabrication is relatively simple, resulting in better overall engineering applicability and reliability. The micro-fish-scale structure can better achieve the cumulative effect.

[0018] For the reasons stated above, this invention can be widely applied in fields such as turbomachinery. Attached Figure Description

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

[0020] Figure 1 This is a schematic diagram of the high-load diffuser cascade structure with localized biomimetic fish scales on the blades of the present invention.

[0021] Figure 2 This is a schematic diagram of a high-load diffuser cascade structure with localized biomimetic fish scale structures on the leading edge end wall of the diffuser cascade plate and the blades of the present invention.

[0022] Figure 3 This is a schematic diagram of a high-load diffuser cascade structure with localized biomimetic fish scale structures on the suction side wall of the diffuser cascade plate and on the blades, as described in this invention.

[0023] Figure 4This is a schematic diagram of the high-load diffuser cascade structure of the present invention, which features a partial biomimetic fish scale structure on the leading edge end wall of the diffuser cascade plate, the suction side end wall, and the blade.

[0024] Figure 5 This is a schematic diagram of the high-load diffuser cascade structure with staggered, locally biomimetic fish scale structures on the blades of the present invention.

[0025] Figure 6 This is a schematic diagram of a single biomimetic fish scale structure of the present invention.

[0026] Figure 7 This is a schematic diagram of the multi-column biomimetic fish scale structure parameters of the present invention.

[0027] Figure 8 This is a schematic diagram of the stator blade structure of a high-load compressor with a localized biomimetic fish scale structure according to the present invention.

[0028] Figure 9 This is a schematic diagram of the stator structure of a high-load compressor with locally biomimetic fish scale structure on the blades of this invention.

[0029] Figure 10 This is a schematic diagram of the stator structure of a high-load compressor with localized biomimetic fish scale structures on the leading edge end wall of the diffuser cascade plate and the blades of the present invention.

[0030] Figure 11 This is a schematic diagram of the stator structure of a high-load compressor with localized biomimetic fish scale structures on the suction side wall of the diffuser cascade plate and on the blades, as described in this invention.

[0031] Figure 12 This is a schematic diagram of the stator structure of a high-load compressor with localized biomimetic fish scale structures on the leading edge end wall of the diffuser cascade plate, the suction side end wall, and the blades of the present invention.

[0032] In the figure: 1. Diffuser cascade; 2. Blade; 3. Bionic fish scale structure; 4. Casing; 5. Hub; 6. Starting position of the flow direction of the bionic fish scale structure; 7. Ending position of the flow direction of the bionic fish scale structure; 8. Starting position of the spanning direction of the bionic fish scale structure; 9. Ending position of the spanning direction of the bionic fish scale structure. Detailed Implementation

[0033] It should be noted that, unless otherwise specified, the embodiments and features described in the present invention can be combined with each other. The present invention will now be described in detail with reference to the accompanying drawings and embodiments.

[0034] To make the objectives, technical solutions, and advantages of the embodiments of the present invention clearer, the technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. The following description of at least one exemplary embodiment is merely illustrative and is in no way intended to limit the present invention or its application or use. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0035] It should be noted that the terminology used herein is for the purpose of describing particular embodiments only and is not intended to limit the scope of exemplary embodiments according to the invention. As used herein, the singular form is intended to include the plural form as well, unless the context clearly indicates otherwise. Furthermore, it should be understood that when the terms "comprising" and / or "including" are used in this specification, they indicate the presence of features, steps, operations, devices, components, and / or combinations thereof.

[0036] Unless otherwise specifically stated, the relative arrangement, numerical expressions, and values ​​of the components and steps described in these embodiments do not limit the scope of the invention. It should also be understood that, for ease of description, the dimensions of the various parts shown in the drawings are not drawn to actual scale. Techniques, methods, and devices known to those skilled in the art may not be discussed in detail, but where appropriate, such techniques, methods, and devices should be considered part of the specification. In all examples shown and discussed herein, any specific values ​​should be interpreted as merely exemplary and not as limitations. Therefore, other examples of exemplary embodiments may have different values. It should be noted that similar reference numerals and letters in the following figures denote similar items; therefore, once an item is defined in one figure, it need not be further discussed in subsequent figures.

[0037] In the description of this invention, it should be understood that the orientation or positional relationship indicated by directional terms such as "front, back, up, down, left, right", "horizontal, vertical, horizontal" and "top, bottom" is generally based on the orientation or positional relationship shown in the accompanying drawings, and is only for the convenience of describing this invention and simplifying the description. Unless otherwise stated, these directional terms do not indicate or imply that the device or element referred to must have a specific orientation or be constructed and operated in a specific orientation, and therefore should not be construed as a limitation on the scope of protection of this invention. The directional terms "inner" and "outer" refer to the inner and outer contours relative to the outline of each component itself.

[0038] For ease of description, spatial relative terms such as "above," "over," "on the upper surface of," "above," etc., are used herein to describe the spatial positional relationship of a device or feature as shown in the figures to other devices or features. It should be understood that spatial relative terms are intended to encompass different orientations in use or operation besides the orientation of the device as described in the figures. For example, if the device in the figures is inverted, a device described as "above" or "above" other devices or structures would subsequently be positioned as "below" or "under" other devices or structures. Thus, the exemplary term "above" can include both "above" and "below." The device may also be positioned in other different ways (rotated 90 degrees or in other orientations), and the spatial relative descriptions used herein will be interpreted accordingly.

[0039] Furthermore, it should be noted that the use of terms such as "first" and "second" to define components is merely for the purpose of distinguishing the corresponding components. Unless otherwise stated, the above terms have no special meaning and therefore should not be construed as limiting the scope of protection of this invention.

[0040] Example 1 With the ever-increasing demands on thrust-to-weight ratio for aero-engines, compressor design faces increasingly severe challenges. To meet these higher thrust-to-weight ratio requirements, the single-stage pressure ratio of the compressor needs to be further improved, while minimizing the number of stages to reduce overall weight. However, increasing the single-stage pressure ratio inevitably leads to higher stage loads, which places higher demands on the aerodynamic design of the blade cascade. Especially in high-load diffuser cascades, the presence of strong adverse pressure gradients often leads to complex three-dimensional flow separation, significantly reducing the flow stability and aerodynamic efficiency of the cascade passages.

[0041] Flow separation not only increases local flow resistance but also induces aerodynamic losses, especially in the endwall region. The secondary flow effect causes low-energy fluid to mix with the mainstream, exacerbating flow losses. This accumulation of low-energy fluid can further clog the flow channels, even leading to compressor stall or surge, severely impacting stable operation and efficiency. Therefore, effectively suppressing flow separation and minimizing its adverse effects on aerodynamic performance has become a key technical challenge for improving the performance of high-load diffuser cascades.

[0042] This invention provides a high-load diffuser cascade with a locally biomimetic fish-scale structure. By optimizing the geometric parameters and arrangement of the biomimetic fish-scale structure, the boundary layer thickness is effectively adjusted, reducing local flow resistance and aerodynamic losses, thereby improving the overall efficiency of the cascade. Especially under high-load conditions, this structure can significantly improve flow stability, suppress the occurrence and spread of flow separation, ensure the efficient operation of the cascade under high-load conditions, and further enhance the aerodynamic performance and stability of the compressor.

[0043] like Figures 1-5 As shown, the high-load diffuser cascade of the present invention is a planar cascade structure, including: a diffuser cascade plate 1 (planar cascade plate), blades 2, and a biomimetic fish scale structure 3. The biomimetic fish scale structure 3 can be arranged alone on the suction surface of the blade 2, alone at the leading edge of the diffuser cascade plate 1, or alone on the side wall of the suction surface of the diffuser cascade plate 1. Alternatively, it can be arranged simultaneously on the suction surface of the blade 2 and the leading edge of the diffuser cascade plate 1, or simultaneously on the suction surface of the blade 2 and the side wall of the suction surface of the diffuser cascade plate 1, or simultaneously on the leading edge of the diffuser cascade plate 1, the side wall of the suction surface of the diffuser cascade plate 1, and the suction surface of the blade 2. That is, there are seven possible combinations, and the biomimetic fish scale structure 3 is partially present on the blade 2 and / or the diffuser cascade plate 1.

[0044] like Figures 9-12 As shown, for a high-load compressor stator, the high-load diffuser cascade is an annular cascade structure, including blades 2, a biomimetic fish scale structure 3, a casing 4, and a hub 5. Blades 2 are positioned between the casing 4 and the hub 5, and are fixed by airfoil grooves on the casing 4 and hub 5. The biomimetic fish scale structure 3 is partially present on the blades 2 and / or the hub 5. The biomimetic fish scale structure 3 can be arranged alone on the suction surface of the blade 2, or alone on the hub 5 at the leading edge of the blade 2, or alone on the hub 5 on the suction side of the blade 2. Alternatively, it can be arranged simultaneously on the suction surface of the blade 2 and the hub 5 at the leading edge of the blade 2, or simultaneously on the suction surface of the blade 2 and the hub 5 on the suction side of the blade 2, or simultaneously on the hub 5 on the suction side of the blade 2 and the hub 5 on the suction side of the blade 2, or simultaneously on the suction surface of the blade 2, the hub 5 at the leading edge of the blade 2, and the hub 5 on the suction side of the blade 2.

[0045] like Figure 8As shown, the blade 2 is provided with a biomimetic fish scale structure 3 array. When the biomimetic fish scale structure 3 array is arranged on the suction surface of the blade 2, there is an arrangement range along the flow direction and an arrangement range in the spanwise direction. That is, the biomimetic fish scale structure 3 array has key features: the flow direction start position 6, the flow direction end position 7, the spanwise start position 8, and the spanwise end position 9 of the biomimetic fish scale structure. The arrangement can be adjusted according to the actual situation.

[0046] The biomimetic fish scale structure 3 is mainly composed of several micro-fish scale structures arranged in an array. The arrangement methods include parallel or staggered arrangements, with the scale spacing as the arrangement parameter. Each individual micro-fish scale structure is a groove with a flat bottom, appearing fan-shaped when viewed from above. The micro-fish scale structure has a certain thickness and a fan-shaped cross-section. The two sides of each micro-fish scale structure are a first arc surface and a second arc surface, with the radius of the first arc surface being smaller than the radius of the second arc surface. The structural parameters of a single micro-fish scale structure include depth. h ,length s ,width l wait.

[0047] Example 2 This invention also provides a design method for a high-load diffuser cascade with a local biomimetic fish-scale structure, comprising the following steps: First, establish a spatial rectangular coordinate system with the center of the biomimetic fish scale structure 3 as the origin o. Eight points are given in this coordinate system, namely: , , , , , , , ; in, ; ; ; ; ; In the formula, This is the starting point on the upper side of the first arc surface of the micro-fish scale structure. This is the upper end point of the first arc surface of the micro-fish scale structure. This is the starting point on the upper side of the second arc surface of the micro-fish scale structure. This is the upper end point of the second arc surface of the micro-fish scale structure. This is the starting point on the lower side of the first arc surface of the micro-fish scale structure. This is the lower end point of the first arc surface of the micro-fish scale structure. This is the starting point on the lower side of the second arc surface of the micro-fish scale structure. This is the lower end point of the second arc surface of the micro-fish scale structure. The length of the microscale structure, The width of the first arc surface of the micro-fish scale structure. The width of the second arc surface of the micro-fish scale structure. The depth of the microscale structure.

[0048] Connect them with straight lines respectively , , , , , , and The first arc surface of the biomimetic fish scale structure , Second arc surface , The curves between these curves are formed using methods including quadratic Bézier curves, cubic Bézier curves, and quadratic B-spline curves. Their specific parametric equations are as follows: ; ; ; In the formula, The governing equations for a quadratic Bézier curve are given. The governing equations for cubic Bézier curves are given. , , , As control points for curve shaping, t The parameter has a range of values. . The governing equations for a quadratic B-spline curve are... It is a quadratic B-spline basis function, and its fundamental condition is when hour, ; Recursive formula for: ; Step one can determine the structural parameters of a single micro-fish scale structure.

[0049] 2. After the structural parameters of a single micro-fish scale structure are determined, numerical calculations are required to determine the spacing between adjacent rows of fish scales and the spacing between different rows of fish scales, and to combine the corresponding position parameters, so as to finally determine the arrangement of the biomimetic fish scale structure 3 on the blade 2. The biomimetic fish scale structure 3 is formed by array arrangement and combination. The blade 2 with the biomimetic fish scale structure 3 is then generated by three-dimensional drawing software. The corresponding diffuser cascade plate 1 (or hub 5) structure can be obtained by further combining parameters such as blade installation angle and pitch.

[0050] Similarly, the aforementioned biomimetic fish scale structure 3 can be arranged on the diffuser blade cascade plate 1 (or hub 5) in a certain form. The arrangement can be parallel or staggered. The parameters of the biomimetic fish scale structure 3 on the diffuser blade cascade plate 1 (or hub 5) can be the same as the dimensions of the biomimetic fish scale structure 3 on the blade 2, or they can be determined separately based on the corresponding numerical calculation results. The parameters and determination method of the biomimetic fish scale structure 3 on the diffuser blade cascade plate 1 (or hub 5) are consistent with the above method.

[0051] The high-load diffuser cascade structure can be either a planar cascade structure or an annular cascade structure. For the planar cascade structure, the designed biomimetic fish scale structure 3 can be either a groove based on the surface of the blade 2 and the diffuser cascade plate 1, or a protrusion based on the surface of the blade 2 and the diffuser cascade plate 1. Based on the above description, the high-load planar diffuser blade with biomimetic fish scale structure 3 can have the following structural forms: (1) biomimetic fish scale structure 3 is arranged alone on the leading edge end wall of the diffuser blade cascade plate 1; (2) biomimetic fish scale structure 3 is arranged alone on the suction surface of the blade 2; (3) biomimetic fish scale structure 3 is arranged alone on the side end wall of the suction surface of the diffuser blade cascade plate 1; (4) biomimetic fish scale structure 3 is arranged simultaneously on the suction surface of the blade 2 and the leading edge end wall of the diffuser blade cascade plate 1; (5) biomimetic fish scale structure 3 is arranged simultaneously on the suction surface of the blade 2 and the side end wall of the suction surface of the diffuser blade cascade plate 1; (6) biomimetic fish scale structure 3 is arranged simultaneously on the leading edge end wall of the diffuser blade cascade plate 1 and the side end wall of the suction surface of the diffuser blade cascade plate 1; (7) biomimetic fish scale structure 3 is arranged simultaneously on the suction surface of the blade 2, the leading edge end wall of the diffuser blade cascade plate 1 and the side end wall of the suction surface of the diffuser blade cascade plate 1. This corresponds to several different combinations of blades 2 and diffuser cascade plates 1: (1) a combination of a leading edge biomimetic fish scale structure cascade plate and a prototype (smooth) blade; (2) a combination of a prototype (smooth) cascade plate and a suction surface biomimetic fish scale structure blade; (3) a suction surface biomimetic fish scale structure cascade plate and a prototype (smooth) blade; (4) a leading edge biomimetic fish scale structure cascade plate and a suction surface biomimetic fish scale structure blade; (5) a suction surface biomimetic fish scale structure cascade plate and a suction surface biomimetic fish scale structure blade; (6) a leading edge and suction surface biomimetic fish scale structure cascade plate and a prototype (smooth) blade; (7) a leading edge and suction surface biomimetic fish scale structure cascade plate and a suction surface biomimetic fish scale structure blade. Among them, all biomimetic fish scale structures 3 include both grooved and protruding types, while the arrangement of the biomimetic fish scale structures 3 of the diffuser cascade plate 1 and blades 2 can be either parallel or staggered.

[0052] For the annular cascade structure, the designed biomimetic fish scale structure 3 can be either a groove on the surface of the blade 2 and the hub 5 or a protrusion on the surface of the blade 2 and the hub 5. Based on the above description, the high-load annular diffuser cascade with biomimetic fish scale structure 3 can have the following structural forms: (1) biomimetic fish scale structure 3 is arranged alone on the leading edge hub 5 of the blade 2; (2) biomimetic fish scale structure 3 is arranged alone on the suction surface of the blade 2; (3) biomimetic fish scale structure 3 is arranged alone on the suction side hub 5 of the blade 2; (4) biomimetic fish scale structure 3 is arranged simultaneously on the suction surface and the leading edge hub 5 of the blade 2; (5) biomimetic fish scale structure 3 is arranged simultaneously on the suction surface and the suction side hub 5 of the blade 2; (6) biomimetic fish scale structure 3 is arranged simultaneously on the leading edge hub 5 and the suction side hub 5 of the blade 2; (7) biomimetic fish scale structure 3 is arranged simultaneously on the suction surface of the blade 2, the leading edge hub 5 of the blade 2, and the suction side hub 5. This corresponds to several different combinations of blades 2 and hubs 5: (1) a hub with a biomimetic fish scale structure at the leading edge of the blade combined with a prototype (smooth) blade; (2) a prototype (smooth) hub combined with a biomimetic fish scale structure blade on the suction surface; (3) a hub with a biomimetic fish scale structure on the suction surface side of the blade combined with a prototype (smooth) blade; (4) a hub with a biomimetic fish scale structure at the leading edge of the blade combined with a biomimetic fish scale structure blade on the suction surface; (5) a hub with a biomimetic fish scale structure on the suction surface side of the blade combined with a biomimetic fish scale structure blade on the suction surface; (6) a hub with a biomimetic fish scale structure at the leading edge and suction surface side combined with a prototype (smooth) blade; and (7) a hub with a biomimetic fish scale structure at the leading edge and suction surface side combined with a biomimetic fish scale structure blade on the suction surface. Among these, all biomimetic fish scale structures 3 include both grooved and protruding types, while the arrangement of the biomimetic fish scale structures 3 of the hub 5 and blades 2 can be either parallel or staggered.

[0053] For example, the arrangement of the biomimetic fish scale structure 3 can be parallel. (See attached image.) Figure 7 As shown, For the spacing between different columns of fish scales, The spacing between adjacent rows of fish scales represents the distance between the scales. By changing the spacing between different columns of fish scales and the spacing between adjacent rows of fish scales, the arrangement structure of the biomimetic fish scales can be controlled.

[0054] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention, and not to limit them; although the present invention has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that modifications can still be made to the technical solutions described in the foregoing embodiments, or equivalent substitutions can be made to some or all of the technical features; and these modifications or substitutions do not cause the essence of the corresponding technical solutions to deviate from the scope of the technical solutions of the embodiments of the present invention.

Claims

1. A high-load diffuser cascade with a locally biomimetic fish-scale structure, characterized in that, The high-load diffuser blade cascade is provided with a biomimetic fish scale structure (3), which is partially present on the high-load diffuser blade cascade; the biomimetic fish scale structure (3) is composed of an array of several micro fish scale structures.

2. The high-load diffuser cascade with a locally biomimetic fish-scale structure according to claim 1, characterized in that, The bottom of the micro-fish scale structure is a plane. The micro-fish scale structure has a certain thickness and a fan-shaped cross-section. The two sides of the micro-fish scale structure are a first arc surface and a second arc surface, respectively. The radius of the first arc surface is smaller than the radius of the second arc surface.

3. The high-load diffuser cascade with a locally biomimetic fish-scale structure according to claim 1, characterized in that, The micro-fish scale structure is in the form of a groove structure or a protruding structure.

4. The high-load diffuser cascade with a locally biomimetic fish-scale structure according to claim 1, characterized in that, The biomimetic fish scale structure (3) is arranged in a parallel or staggered manner, and the arrangement parameter is the fish scale spacing.

5. The high-load diffuser cascade with a locally biomimetic fish-scale structure according to claim 1, characterized in that, The high-load diffuser cascade is a planar cascade structure or an annular cascade structure. The planar cascade structure is partially provided with a biomimetic fish scale structure (3), and the annular cascade structure is partially provided with a biomimetic fish scale structure (3).

6. The high-load diffuser cascade with a locally biomimetic fish-scale structure according to claim 5, characterized in that, The planar blade cascade structure includes a diffuser cascade plate (1) and a blade (2). The blade (2) is fixedly connected to the diffuser cascade plate (1). The biomimetic fish scale structure (3) is partially present on the blade (2) and / or the diffuser cascade plate (1). Wherein, the biomimetic fish scale structure (3) is arranged alone on the suction surface of the blade (2); or, the biomimetic fish scale structure (3) is arranged alone at the leading edge of the diffuser cascade plate (1); or, the biomimetic fish scale structure (3) is arranged alone at the side wall of the suction surface of the diffuser cascade plate (1); or, the biomimetic fish scale structure (3) is arranged simultaneously on the suction surface of the blade (2) and the leading edge of the diffuser cascade plate (1); or, the biomimetic fish scale structure (3) is arranged on both the suction surface of the blade (2) and the leading edge of the diffuser cascade plate (1); The fish scale structure (3) is simultaneously arranged on the suction surface of the blade (2) and the side wall of the suction surface of the diffuser cascade plate (1); or, the biomimetic fish scale structure (3) is simultaneously arranged on the leading edge of the diffuser cascade plate (1) and the side wall of the suction surface of the diffuser cascade plate (1); or, the biomimetic fish scale structure (3) is simultaneously arranged on the leading edge of the diffuser cascade plate (1), the side wall of the suction surface of the diffuser cascade plate (1), and the suction surface of the blade (2).

7. The high-load diffuser cascade with a locally biomimetic fish-scale structure according to claim 5, characterized in that, The annular blade cascade structure includes blades (2), a casing (4) and a hub (5). The blades (2) are fixedly connected to the blade-shaped grooves provided on the casing (4) and the hub (5). The biomimetic fish scale structure (3) is partially present on the blades (2) and / or the hub (5). Wherein, the biomimetic fish scale structure (3) is arranged alone on the suction surface of the blade (2); or, the biomimetic fish scale structure (3) is arranged alone on the hub (5) of the leading edge of the blade (2); or, the biomimetic fish scale structure (3) is arranged alone on the hub (5) on the suction surface side of the blade (2); or, the biomimetic fish scale structure (3) is arranged simultaneously on the suction surface of the blade (2) and the hub (5) of the leading edge of the blade (2); or, the biomimetic fish scale structure (3) is arranged on both the suction surface of the blade (2) and the hub (5) of the leading edge of the blade (2); The fish scale structure (3) is simultaneously arranged on the suction surface of the blade (2) and the hub (5) on the suction surface side of the blade (2); or, the biomimetic fish scale structure (3) is simultaneously arranged on the hub (5) on the suction surface side of the blade (2) and the hub (5) on the suction surface side of the blade (2); or, the biomimetic fish scale structure (3) is simultaneously arranged on the suction surface of the blade (2), the hub (5) on the leading edge of the blade (2) and the hub (5) on the suction surface side of the blade (2).

8. A design method for a high-load diffuser cascade with a locally biomimetic fish-scale structure as described in any one of claims 1-7, characterized in that, Includes the following steps: S1. Establish a spatial rectangular coordinate system with the center of the biomimetic fish scale structure (3) as the origin o, and give eight points in the spatial rectangular coordinate system to determine the structural parameters of a single micro-fish scale structure. The structural parameters of a single micro-fish scale structure include depth. h ,length s ,width l ; S2. After the structural parameters of a single micro-fish scale structure are determined, numerical calculations are performed to determine the spacing between adjacent rows of fish scales and the spacing between different rows of fish scales. Combined with the corresponding position parameters, the arrangement of the biomimetic fish scale structure (3) on the diffuser cascade plate (1), blade (2) and hub (5) is finally determined. Parallel or staggered arrangement is adopted, and the array arrangement is combined to form the profile of the biomimetic fish scale structure (3). The corresponding diffuser cascade plate (1), blade (2) and hub (5) structure with biomimetic fish scale structure (3) are further generated.

9. The design method for a high-load diffuser cascade with a locally biomimetic fish-scale structure according to claim 8, characterized in that, In S1, the eight given points are as follows: , , , , , , , ; in, ； ； ； ； ； In the formula, This is the starting point on the upper side of the first arc surface of the micro-fish scale structure. This is the upper end point of the first arc surface of the micro-fish scale structure. This is the starting point on the upper side of the second arc surface of the micro-fish scale structure. This is the upper end point of the second arc surface of the micro-fish scale structure. This is the starting point on the lower side of the first arc surface of the micro-fish scale structure. This is the lower end point of the first arc surface of the micro-fish scale structure. This is the starting point on the lower side of the second arc surface of the micro-fish scale structure. This is the lower end point of the second arc surface of the micro-fish scale structure. The length of the microscale structure, The width of the first arc surface of the micro-fish scale structure. The width of the second arc surface of the micro-fish scale structure. The depth of the micro-fish scale structure; Connect them with straight lines respectively , , , , , , and ; Bionic fish scale structure first arc surface , Second arc surface , The curves between these curves can be modeled using methods such as quadratic Bézier curves, cubic Bézier curves, and quadratic B-spline curves. The specific parametric equations are as follows: ； ； ； In the formula, The governing equations for a quadratic Bézier curve are given. The governing equations for cubic Bézier curves are given. , , , As control points for curve shaping, t The parameter has a range of values. ; The governing equations for a quadratic B-spline curve are... It is a quadratic B-spline basis function, and its fundamental condition is when hour, ； Recursive formula for: 。 10. The design method for a high-load diffuser cascade with a locally biomimetic fish-scale structure according to claim 8, characterized in that, In S2, the parameters of the biomimetic fish scale structure (3) on the diffuser grating plate (1) or hub (5) are the same as the size of the biomimetic fish scale structure (3) on the blade (2), or are determined separately based on the corresponding numerical calculation results.

Images