Hydraulic turbine top cover and hydraulic turbine

Abstract

The application provides a water turbine top cover and a water turbine. The water turbine top cover comprises a first top cover, the first top cover comprises a first ring plate, a second ring plate and a first rib plate. The second ring plate is arranged opposite to the first ring plate; the first rib plate is located between the first ring plate and the second ring plate, the first rib plate comprises a first end face and a second end face arranged opposite to each other, the first end face is connected with the first ring plate, the second end face is connected with the second ring plate, the first top cover further comprises a first side face and a second side face arranged opposite to each other, the first side face is located on one side of the second side face close to the flow passage; the width of the first end face is smaller than the width of the second end face in the direction of the first side face pointing to the second side face; the first side face comprises a first sub-side face, a second sub-side face and a third sub-side face connected in sequence, the first sub-side face is connected with the first end face, the third sub-side face is connected with the second end face, and the second sub-side face is arranged to be inclined to the direction away from the second side face relative to the first sub-side face. The stress concentration can be improved.

Description

Technical Field

[0001] This application relates to the field of water turbine technology, specifically to a water turbine top cover and a water turbine. Background Technology

[0002] A hydroelectric turbine is a power machine that converts water energy into rotational mechanical energy and is the core equipment of a hydroelectric power station. The turbine roof, as a key fixed component, withstands water pressure and pressure pulsations under various operating conditions. It also provides the mounting foundation for guide vanes, water guide bearings, and other components; its rigidity directly affects the unit's operational stability. The roof structure endures complex and variable high-amplitude water pressure, with stress levels constantly changing over time and depending on operating conditions. High-amplitude, unstable axial water thrust can cause significant deformation and stress concentration in the roof, leading to cracks, structural damage, and even major accidents resulting in the destruction of the hydroelectric power station and loss of life. Summary of the Invention

[0003] This application addresses the shortcomings of related technologies by proposing a turbine top cover and a turbine to solve the problem of stress concentration caused by ribs in related technologies.

[0004] This application embodiment provides a turbine top cover, including a first top cover, the first top cover having a flow channel, the first top cover comprising: First ring plate; The second ring plate is disposed opposite to the first ring plate; A first rib is located between the first ring plate and the second ring plate. The first rib includes a first end face and a second end face disposed opposite to each other. The first end face is connected to the first ring plate, and the second end face is connected to the second ring plate. The first top cover also includes a first side face and a second side face disposed opposite to each other. The first side face is located on the side of the second side face closer to the flow channel. Along the direction from the first side face to the second side face, the width of the first end face is smaller than the width of the second end face. The first side face includes a first sub-side face, a second sub-side face, and a third sub-side face that are connected in sequence. The first sub-side face is connected to the first end face, and the third sub-side face is connected to the second end face. The second sub-side face is inclined relative to the first sub-side face in a direction away from the second side face.

[0005] In some embodiments, along the direction from the first annular plate to the second annular plate, The height of the second sub-side is greater than the height of the first sub-side; And / or, the height of the second sub-side is greater than the height of the third sub-side.

[0006] In some embodiments, the width of the second sub-side is smaller than the width of the first end face in the direction from the first side face to the second side face.

[0007] In some embodiments, the included angle between the second sub-side face and the second end face is greater than 45°.

[0008] In some embodiments, the first rib further includes a first plate surface and a second plate surface disposed opposite to each other. The first plate surface is connected to the first end face and the second end face, and the second plate surface is connected to the first end face and the second end face. Both the first plate surface and the second plate surface are parallel to the direction from the first ring plate to the second ring plate. The first rib is provided with a hollow hole, and the extension direction of the hollow hole is parallel to at least one of the first plate surface and the second plate surface.

[0009] In some embodiments, the direction in which the perforated hole extends is parallel to the direction from the first end face to the second end face.

[0010] In some embodiments, the cross-sectional profile of the perforated hole in the direction perpendicular to the axis is circular, elliptical, or waist-shaped.

[0011] In some embodiments, the first rib further includes a first plate surface and a second plate surface disposed opposite to each other, the first plate surface being connected to the first end face and the second end face, and the second plate surface being connected to the first end face and the second end face, wherein both the first plate surface and the second plate surface are parallel to the direction pointing from the first ring plate to the second ring plate; wherein. The first ring plate includes a first ring surface facing the second ring plate, and the connection between the first plate surface and / or the second plate surface and the first ring surface is provided with a rounded corner structure, and the first plate surface and / or the second plate surface and the first ring surface are smoothly transitioned through the rounded corner structure; And / or, the second ring plate includes a second ring surface facing the first ring plate, and the connection between the first plate surface and / or the second plate surface and the second ring surface is provided with a rounded corner structure, and the first plate surface and / or the second plate surface and the second ring surface are smoothly transitioned through the rounded corner structure.

[0012] In some embodiments, the turbine top cover further includes a second top cover, which is sleeved on the outside of the first top cover.

[0013] This application also provides a water turbine, including the water turbine top cover as described above.

[0014] The beneficial effects of this application include: When the turbine top cover provided in this application is inclined in a direction away from the second side relative to the first side, the stress at the junction between the second side and the first side can be reduced, stress concentration in the first rib can be avoided, the deformation resistance can be enhanced, and the service life of the first rib can be improved.

[0015] Additional aspects and advantages of this application will be set forth in part in the description which follows, and will become apparent from the description or may be learned by practice of this application. Attached Figure Description

[0016] The accompanying drawings, which are incorporated in and form part of this specification, illustrate embodiments consistent with this application and, together with the description, serve to explain the principles of this application.

[0017] Figure 1 The diagram shown is a structural schematic of a rib plate in the top cover of a water turbine in the related art; Figure 2 The diagram shown is a structural schematic of a turbine top cover provided in an exemplary embodiment of this application; Figure 3 As shown Figure 2 A schematic diagram of the structure of the first rib plate in the top cover of a medium-sized hydro turbine; Figures 4-6 As shown Figure 3 Schematic diagrams of the first rib plate from different perspectives; Figure 7 The diagram shown is a finite element mesh representation of the structure of the first rib provided in an exemplary embodiment of this application. Figure 8 Figures (a) and (b) show the stress distribution of a rib plate in the related art and a first rib plate provided in an exemplary embodiment of this application under the same force, respectively. Figure 9 Figures (a) and (b) show the deformation distribution of the rib plate in the related art and the first rib plate provided in an exemplary embodiment of this application under the same force, respectively. Figure 10 The diagram shown is a structural schematic of a turbine top cover provided in another exemplary embodiment of this application; Figure 11 The diagram shown is a structural schematic of a water turbine provided in an exemplary embodiment of this application.

[0018] In the diagram: 1-Water turbine; 10-Water turbine top cover; 100-First top cover; 110-First ring plate; 120-First ring plate; 130-First rib plate; 130a-Perforated hole; 131-First end face; 132-Second end face; 133-First side face; 1331-First sub-side face; 1332-Second sub-side face; 1333-Third sub-side face; 134-Second side face; 100a-Flow passage; 135-First plate surface; 136-Second plate surface; 140-Rounded corner structure; 200-Second top cover; 210-Third ring plate; 220-Fourth ring plate; 230-Second rib plate; 20-Vortex casing; 30-Runner; 40-Guide vane. Detailed Implementation

[0019] The present application will be described more fully below with reference to the accompanying drawings in which embodiments are illustrated.

[0020] While terms such as "first," "second," etc., can be used to describe various components, such components are not limited by these terms. These terms are only used to distinguish one component from another and should not be construed as indicating or implying relative importance or implicitly specifying the number of technical features indicated. Thus, a feature defined with "first," "second," etc., may explicitly or implicitly include one or more of that feature. In the description of this application, unless otherwise stated, "a plurality of" means two or more. Where there is no conflict, the features in the embodiments described below in this application may complement or combine with each other.

[0021] In the accompanying drawings, the symbols "x", "y", and "z" are used to indicate directions. The x, y, and z directions are not limited to three mutually perpendicular directions in a Cartesian coordinate system and can be interpreted in a broader sense. For example, the x, y, and z directions can be perpendicular to each other, or they can represent different directions that are not perpendicular to each other. Exemplarily, x indicates a first direction, y indicates a second direction perpendicular to the first direction, and z indicates a third direction perpendicular to both the first and second directions. The first direction x, the second direction y, and the third direction z can correspond to the horizontal, vertical, and height directions of the first rib in the turbine top cover, respectively.

[0022] In the accompanying drawings, the dimensions and thicknesses of the elements may be enlarged for better understanding, clarity, and ease of description. However, this application is not limited to the dimensions and thicknesses shown in the drawings. The thicknesses of layers, films, panels, areas, and other elements may be exaggerated in the drawings for clarity. Example embodiments are shown in the drawings, wherein the same reference numerals denote the same elements.

[0023] Figure 1 The diagram shows a structural schematic of a rib plate in the top cover of a water turbine in related technologies. Figure 1As shown, since the rib 130' has a notch 131', stress concentration is likely to occur at the notch 131', which may lead to the risk of cracking and damage to the rib 130'.

[0024] This application provides a turbine top cover 10 and a turbine 1, which are intended to solve or improve the above-mentioned technical problems.

[0025] This application provides a turbine top cover 10, such as Figures 2-6 As shown, the device includes a first top cover 100, which has a flow channel 100a. The first top cover 100 includes a first ring plate 110, a second ring plate 120, and a first rib plate 130, wherein the second ring plate 120 is disposed opposite to the first ring plate 110, and the first rib plate 130 is located between the first ring plate 110 and the second ring plate 120.

[0026] The first rib 130 includes a first end face 131 and a second end face 132 disposed opposite to each other. The first end face 131 is connected to the first ring plate 110, and the second end face 132 is connected to the second ring plate 120. The first top cover 100 also includes a first side face 133 and a second side face 134 disposed opposite to each other. The first side face 133 is located on the side of the second side face 134 near the flow channel 100a. In the direction from the first side face 133 to the second side face 134, the width of the first end face 131 is smaller than the width of the second end face 132. The first side face 133 includes a first sub-side face 1331, a second sub-side face 1332 and a third sub-side face 1333 connected in sequence. The first sub-side face 1331 is connected to the first end face 131, and the third sub-side face 1333 is connected to the second end face 132. The second sub-side face 1332 is inclined relative to the first sub-side face 1331 in a direction away from the second side face 134.

[0027] In this embodiment, experimental verification shows that when the second sub-side surface 1332 is inclined relative to the first sub-side surface 1331 in a direction away from the second sub-side surface 134, the stress at the interface between the second sub-side surface 1332 and the first sub-side surface 1331 can be reduced, avoiding stress concentration in the first rib 130, enhancing its resistance to deformation, and thus improving the service life of the first rib 130. It should be noted that in this embodiment, a model is established using finite element analysis to analyze the stress distribution and deformation under stress at various points on the first rib 130. Comparing the turbine top cover 10 provided in related technologies with the turbine top cover 10 used in this embodiment, the turbine top cover 10 provided in this embodiment shows significantly improved stress concentration and significantly reduced deformation under the same conditions.

[0028] For example, stress distribution can be simulated using the following methods: Step 1: Establish three-dimensional models as described in relevant technologies and as provided in an exemplary embodiment of this application; Step Two: Based on the finite element theory, the two models above are meshed using finite element methods, and the mesh is refined in areas with significant curvature changes, such as... Figure 7 The diagram shows a division of a model of the first rib provided in an exemplary embodiment of this application; Step 3: Define the boundary conditions and solution methods for stress and total deformation analysis; Based on the actual engineering requirements, material parameters are set, including density, elastic modulus, Poisson's ratio, etc. Fixed constraints are set on the sides of the rib plate, and displacement degrees of freedom are set on the upper and lower end faces. A preset force, such as 1×10⁻⁶, is applied to the upper end face. 6 The force of N.

[0029] Configure the computational resources required for the solution, and focus on stress distribution and total displacement.

[0030] Step 4: Based on Step 3, calculate the maximum and minimum stresses and total displacements according to the finite element formula (1), and compare the design scheme of this patent with the original technical scheme.

[0031] (1) The structural mass matrix, Here is the structural damping matrix. Here is the structural stiffness matrix. For displacement.

[0032] The final calculated results of stress and total deformation are shown in Figure 8. Figure 9 As shown, where, Figure 8 Figures (a) and (b) show the stress distribution of a rib plate in the related art and a first rib plate provided in an exemplary embodiment of this application under the same force, respectively. Figure 9 Figures (a) and (b) show the deformation distribution of a rib plate in the related art and a first rib plate provided in an exemplary embodiment of this application under the same force, respectively. It can be seen that the stress concentration of the first rib plate provided in this embodiment is significantly improved, and the degree of deformation is also greatly reduced.

[0033] In some embodiments, such as Figure 3 and Figure 4 As shown, the second sub-side 1332 and the first sub-side 1331 are connected at an angle. Specifically, the second sub-side 1332 and the first sub-side 1331 intersect at an obtuse angle.

[0034] In some embodiments, the second sub-side surface 1332 and the third sub-side surface 1333 are connected at an angle. Specifically, the second sub-side surface 1332 and the third sub-side surface 1333 intersect at an obtuse angle.

[0035] In some embodiments, the first side surface 133 is connected to the first end surface 131 and the second end surface 132, and the second side surface 134 is connected to the first end surface 131 and the second end surface 132.

[0036] In some embodiments, the first rib 130 and the first ring plate 110 are an integral structure. This improves structural stability. In other embodiments, the first rib 130 and the second ring plate 120 are an integral structure.

[0037] In some embodiments, such as Figure 4 As shown, in the direction from the first ring plate 110 to the second ring plate 120, the height h2 of the second sub-side surface 1332 is greater than the height h1 of the first sub-side surface 1331. Therefore, the angle of inclination of the second sub-side surface 1332 relative to the second side surface 134 can be set to be smaller, thereby increasing the supporting force of the rib plate in the direction from the first ring plate 110 to the second ring plate 120.

[0038] In some embodiments, in the direction from the first ring plate 110 to the second ring plate 120, the height h2 of the second sub-side surface 1332 is greater than the height h3 of the third sub-side surface 1333. Similarly to the aforementioned embodiments, this can improve the supporting force.

[0039] In some embodiments, in the direction from the first side surface 133 to the second side surface 134, the width w2 of the second sub-side surface 1332 is smaller than the width w1 of the first end face 131. Therefore, when the overall width of the rib is constant, the width of the portion containing the first end face 131 is larger, meaning the contact area between the first end face 131 and the first ring plate 110 is larger, which can improve the stability of the first end face 131 supporting the first ring plate 110.

[0040] In some embodiments, the included angle θ between the second sub-side surface 1332 and the second end face 132 is greater than 45°. Therefore, the second sub-side surface 1332 has a greater steepness, meaning that the second sub-side surface 1332 provides greater support to the first ring plate 110, thereby improving the overall compressive strength of the turbine 1. For example, the included angle θ between the second sub-side surface 1332 and the second end face 132 can be 50°, 60°, 70°, 80°, etc.

[0041] In some embodiments, such as Figure 3As shown, the first rib 130 also includes a first plate surface 135 and a second plate surface 136 disposed opposite to each other. The first plate surface 135 is connected to the first end surface 131 and the second end surface 132, and the second plate surface 136 is connected to the first end surface 131 and the second end surface 132. The first plate surface 135 and the second plate surface 136 are both parallel to the direction from the first ring plate 110 to the second ring plate 120. The first rib 130 is provided with a hollow hole 130a, and the extension direction of the hollow hole 130a is parallel to at least one of the first plate surface 135 and the second plate surface 136.

[0042] In this embodiment, since the first rib 130 is provided with a hollow hole 130a, and since the hollow hole 130a does not penetrate the first plate surface 135 or the second plate surface 136, the supporting force of the first rib 130 on the first ring plate 110 or the second ring plate 120 can be reduced as much as possible, while the overall weight of the first rib 130 can be reduced, thus achieving structural lightweighting.

[0043] In some embodiments, such as Figure 5 and Figure 6 As shown, the first plate surface 135 and the second plate surface 136 are parallel, and the extension direction of the perforated hole 130a is parallel to both the first plate surface 135 and the second plate surface 136. In some other embodiments, the first plate surface 135 and the second plate surface 136 may also form a certain angle. In this case, the extension direction of the perforated hole 130a may be parallel to the first plate surface 135 or parallel to the second plate surface 136.

[0044] In some embodiments, such as Figure 3 As shown, the extension direction of the perforated hole 130a is parallel to the direction from the first end face 131 to the second end face 132. Thus, the portion of the first rib plate extending in the direction from the first ring plate 110 to the second ring plate 120 is continuous and uninterrupted, so as to reduce weight while minimizing the reduction of the supporting force of the first rib plate 130.

[0045] In some embodiments, the perforation 130a penetrates at least one of the first end face 131 and the second end face 132. This facilitates the fabrication of the perforation 130a on the first rib 130. In some embodiments, both the first end face 131 and the second end face 132 are penetrated by the perforation 130a.

[0046] In some embodiments, the cross-sectional profile of the perforated hole 130a in the direction perpendicular to the axis is circular, elliptical, or oblong. This avoids stress concentration at sharp junctions, as is the case when forming triangular or square holes.

[0047] In some embodiments, such as Figure 2 and Figure 10As shown, the first ring plate 110 includes a first ring surface (not shown) facing the second ring plate 120. A rounded corner structure 140 is provided at the connection between the first plate surface 135 and / or the second plate surface 136 and the first ring surface, and the first plate surface 135 and / or the second plate surface 136 and the first ring surface are smoothly transitioned through the rounded corner structure 140.

[0048] Therefore, while the first rib 130 provides support, the rounded corner structure 140 can guide the fluid, reducing the direct impact of the fluid on the first rib 130. Specifically, when the fluid flows through the turbine top cover 10, it mainly flows circumferentially and radially along the surface of the turbine top cover 10. Compared to when the rounded corner structure 140 is not provided, the fluid experiences impact at the interface between the rib and the first annular surface, resulting in sudden changes in velocity and pressure, leading to separation and backflow, and thus forming a vortex structure. The rounded corner structure 140 provided in this embodiment allows the fluid to flow smoothly along the smooth rounded corner surface when flowing through the rounded corner structure 140, reducing local flow separation and reducing the impact of the fluid on the first rib 130. At the same time, the rounded corner structure 140 can effectively alleviate stress concentration at the edge of the first rib 130, allowing the load to be transferred more evenly to the top cover body along the first rib 130, thereby improving the structural fatigue life and operational reliability.

[0049] In other embodiments, such as Figure 2 and Figure 10 As shown, the second annular plate 120 includes a second annular surface (not shown) facing the first annular plate 110. A rounded corner structure 140 is provided at the connection between the first plate surface 135 and / or the second plate surface 136 and the second annular surface, allowing for a smooth transition between the first plate surface 135 and / or the second plate surface 136 and the second annular surface. Similar to the aforementioned embodiments, further details are omitted here.

[0050] In some embodiments, the first plate surface 135, the rounded corner structure 140, and the first ring plate 110 are an integral structure. This further enhances the structural support capacity. In other embodiments, the second plate surface 136, the rounded corner structure 140, and the first ring plate 110 are an integral structure.

[0051] In some embodiments, such as Figure 2 As shown, the turbine top cover 10 also includes a second top cover 200, which is fitted onto the outside of the first top cover 100.

[0052] In some embodiments, the second top cover 200 includes a third ring plate 210, a fourth ring plate 220, and a second rib 230 located between the third ring plate 210 and the fourth ring plate 220. The second rib 230 provides support for the third ring plate 210.

[0053] Based on the same inventive concept, this application also provides a water turbine 1, such as Figure 11 As shown, the turbine includes the turbine top cover 10 provided in the aforementioned embodiment. The turbine 1 also includes structures such as a volute 20, a runner 30, and guide vanes 40.

[0054] It should be understood that the embodiments described herein should be considered in a descriptive sense only and not for limiting purposes. The description of features or aspects within each embodiment should generally be considered as other similar features or aspects that may be used in other embodiments. Although one or more embodiments have been described with reference to the accompanying drawings, it will be understood by those skilled in the art that various changes in form and detail may be made therein without departing from the spirit and scope defined by the claims and their equivalents.

Claims

1. A turbine top cover, characterized in that, The first top cover includes a flow channel and comprises: First ring plate; The second ring plate is disposed opposite to the first ring plate; A first rib is located between the first ring plate and the second ring plate. The first rib includes a first end face and a second end face disposed opposite to each other. The first end face is connected to the first ring plate, and the second end face is connected to the second ring plate. The first top cover also includes a first side face and a second side face disposed opposite to each other. The first side face is located on the side of the second side face closer to the flow channel. Along the direction from the first side face to the second side face, the width of the first end face is smaller than the width of the second end face. The first side face includes a first sub-side face, a second sub-side face, and a third sub-side face that are connected in sequence. The first sub-side face is connected to the first end face, and the third sub-side face is connected to the second end face. The second sub-side face is inclined relative to the first sub-side face in a direction away from the second side face.

2. The turbine top cover according to claim 1, characterized in that, Along the direction from the first ring plate to the second ring plate, The height of the second sub-side is greater than the height of the first sub-side; And / or, the height of the second sub-side is greater than the height of the third sub-side.

3. The turbine top cover according to claim 1, characterized in that, Along the direction from the first side to the second side, the width of the second sub-side is smaller than the width of the first end face.

4. The turbine top cover according to claim 1, characterized in that, The angle between the second sub-side face and the second end face is greater than 45°.

5. The turbine top cover according to claim 1, characterized in that, The first rib also includes a first plate surface and a second plate surface disposed opposite to each other. The first plate surface is connected to the first end face and the second end face, and the second plate surface is connected to the first end face and the second end face. Both the first plate surface and the second plate surface are parallel to the direction from the first ring plate to the second ring plate. The first rib is provided with a hollow hole, and the extension direction of the hollow hole is parallel to at least one of the first plate surface and the second plate surface.

6. The turbine top cover according to claim 5, characterized in that, The direction in which the perforated hole extends is parallel to the direction from the first end face to the second end face.

7. The turbine top cover according to claim 5, characterized in that, The cross-sectional profile of the perforated hole perpendicular to the axis is circular, elliptical, or waist-shaped.

8. The turbine top cover according to claim 1, characterized in that, The first rib also includes a first plate surface and a second plate surface disposed opposite to each other. The first plate surface is connected to the first end face and the second end face, and the second plate surface is connected to the first end face and the second end face. Both the first plate surface and the second plate surface are parallel to the direction pointing from the first ring plate to the second ring plate. The first ring plate includes a first ring surface facing the second ring plate, and the connection between the first plate surface and / or the second plate surface and the first ring surface is provided with a rounded corner structure, and the first plate surface and / or the second plate surface and the first ring surface are smoothly transitioned through the rounded corner structure; And / or, the second ring plate includes a second ring surface facing the first ring plate, and the connection between the first plate surface and / or the second plate surface and the second ring surface is provided with a rounded corner structure, and the first plate surface and / or the second plate surface and the second ring surface are smoothly transitioned through the rounded corner structure.

9. The turbine top cover according to claim 1, characterized in that, The turbine top cover also includes a second top cover, which is fitted over the outside of the first top cover.

10. A water turbine, characterized in that, Including the turbine top cover as described in any one of claims 1 to 9.

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