Combined offshore wind power foundation anti-scour device

Abstract

The present invention discloses a combined offshore wind power foundation anti-scour device, comprising a pile foundation, a plurality of spoiler ribs and a riprap layer, wherein the plurality of spoiler ribs are arranged at intervals around the pile foundation, one end of the spoiler rib is connected to the outer peripheral surface of the pile foundation, and the other end extends in a direction away from the pile foundation, the extension length of the spoiler rib is 0.1D-0.67D, the plane where the spoiler rib is located is perpendicular to the seabed surface, the vertical height is greater than or equal to 0.2D, and at least a portion of the spoiler rib is located above the seabed surface, wherein D is the outer diameter of the pile foundation, the riprap layer is located on the outside of the spoiler rib and is laid on the seabed around the pile foundation and the spoiler rib. The combined offshore wind power foundation anti-scour device provided by the present invention has an active anti-scour structure and a passive anti-scour structure, thereby combining the active and passive anti-scour effects, effectively protecting the seabed around the pile foundation, and also has the characteristics of simple structure, easy installation, significant effect and low cost.

Description

Technical Field

[0001] The present invention relates to the technical field of offshore wind power, and in particular to a combined offshore wind power foundation anti-scour device. Background Art

[0002] The stability of wind power foundations is crucial to the safe operation of offshore wind turbines. In the marine environment, under the combined effects of waves, tides, and currents, the seabed is naturally eroded and deposited actively. After the construction of offshore wind turbines, scour pits formed by the superposition of natural scour and local scour are very likely to appear around the pile foundation, resulting in a decrease in the bearing capacity of the wind turbine foundation, a decrease in the natural frequency of the wind turbine support structure, and an increase in foundation deformation, threatening the safe operation of the wind turbine support structure.

[0003] Upstream flow is subject to an adverse pressure gradient in front of the pile foundation, causing the boundary layer to be lifted by the return flow, leading to flow separation and the formation of horseshoe vortices. Horseshoe vortices are the primary cause of localized scour on the seabed around the pile foundation. Reducing the impact of horseshoe vortices on the seabed is one of the effective measures to reduce seabed scour.

[0004] Common anti-scour measures in related technologies can be mainly divided into active protection and passive protection. The principle of active protection measures is to reduce the intensity of the incoming flow and reduce the strength of the vortex structure caused by local scour of the pile foundation. Common active protection solutions include guard ring protection, sacrificial pile protection, downstream stone slab protection, etc. The principle of the passive protection solution is to lay a reinforcement layer around the pile foundation to improve the anti-scour performance of the sediment around the pile. However, the above-mentioned offshore wind power foundation scour protection has the problems of limited functions and poor anti-scour effect. Summary of the Invention

[0005] The present invention aims to solve one of the technical problems in the related art to at least a certain extent. To this end, an embodiment of the present invention provides a combined offshore wind power foundation anti-scour device.

[0006] The combined offshore wind power foundation anti-scour device of an embodiment of the present invention includes: a pile foundation, a portion of which is buried downward in the seabed; a plurality of spoiler ribs, which are arranged at intervals around the pile foundation, one end of the spoiler rib is connected to the outer peripheral surface of the pile foundation, and the other end extends away from the pile foundation, the extension length of the spoiler rib is 0.1D-0.67D, the plane where the spoiler rib is located is perpendicular to the seabed surface, the vertical height is greater than or equal to 0.2D, and at least a portion of the spoiler rib is located above the seabed surface, where D is the outer diameter of the pile foundation; and a riprap layer, which is located on the outside of the spoiler ribs and is laid on the seabed around the pile foundation and the spoiler ribs.

[0007] The combined offshore wind power foundation anti-scour device provided by the embodiment of the present invention has an active anti-scour structure and a passive anti-scour structure, thereby combining the active and passive anti-scour effects to effectively protect the seabed within a certain range around the pile foundation. The active anti-scour structure (spoiler ribs) can effectively protect the seabed around the pile foundation and the area covered by the spoiler ribs; the passive anti-scour structure (riprap layer) can quickly and effectively protect the scour area outside the active anti-scour area. In addition, the anti-scour device provided by the embodiment of the present invention has a simple structure, is easy to install, has significant effects, and is low in cost.

[0008] In some embodiments, the spoiler ribs include at least four spoiler ribs arranged at equal intervals around the pile foundation.

[0009] In some embodiments, the spoiler ribs extend in a radial direction of the pile foundation.

[0010] In some embodiments, the anti-scour device further comprises a collar, the collar being sleeved on the pile foundation and connected to the pile foundation, and the spoiler rib being connected to the outer circumference of the collar.

[0011] In some embodiments, the bottom of the spoiler rib is flush with the seabed surface; or, the bottom of the spoiler rib is buried in the seabed; or, the bottom of the spoiler rib is located above the seabed surface and the distance between the bottom and the seabed surface is less than or equal to 0.1D.

[0012] In some embodiments, the maximum outer diameter of the riprap layer is 5D.

[0013] In some embodiments, the top surface of the riprap layer is flush with the seabed or located above the seabed.

[0014] In some embodiments, the riprap layer includes sand and gravel of various particle sizes, and the median diameter of the sand and gravel ranges from 5 cm to 50 cm.

[0015] In some embodiments, the spoiler rib has a thickness of 0.01D-0.02D.

[0016] In some embodiments, a distance between an inner side of the riprap layer and an outer end of the spoiler rib in a radial direction of the pile foundation is less than or equal to 0.1D. BRIEF DESCRIPTION OF THE DRAWINGS

[0017] Figure 1 It is a front view of a combined offshore wind power foundation anti-scour device provided by an embodiment of the present invention.

[0018] Figure 2 It is a top view of the combined offshore wind power foundation anti-scour device provided by an embodiment of the present invention.

[0019] Figure 3 It is a three-dimensional structural diagram of the spoiler rib and the sleeve provided in an embodiment of the present invention.

[0020] Figure 4 This is the effect of the anti-scour device provided by the embodiment of the present invention on the shear stress of the seabed surface.

[0021] Reference numerals:

[0022] Anti-scour device 100 , pile foundation 1 , spoiler ribs 2 , riprap layer 3 , collar 4 , seabed 5 , seabed surface 6 . DETAILED DESCRIPTION

[0023] The embodiments of the present invention are described in detail below, and examples of the embodiments are shown in the accompanying drawings. The embodiments described below with reference to the accompanying drawings are exemplary and intended to be used to explain the present invention, but should not be understood as limiting the present invention.

[0024] The following is based on Figure 1-Figure 4 The present invention provides a combined offshore wind turbine foundation anti-scour device 100. The anti-scour device 100 includes a pile foundation 1, a plurality of flow-disrupting ribs 2, and a riprap layer 3. A portion of the pile foundation 1 is buried downward in the seabed 5. The plurality of flow-disrupting ribs 2 are spaced apart around the pile foundation 1. One end of each flow-disrupting rib 2 is connected to the outer peripheral surface of the pile foundation 1, and the other end extends away from the pile foundation 1. The extension length of the flow-disrupting rib 2 is 0.1D-0.67D. The plane of the flow-disrupting rib 2 is perpendicular to the seabed 6, with a vertical height greater than 0.2D. At least a portion of the flow-disrupting rib 2 is located above the seabed 6, where D is the outer diameter of the pile foundation 1. The riprap layer 3 is located outside the flow-disrupting rib 2 and is laid on the seabed 5 around the pile foundation 1 and the flow-disrupting rib 2.

[0025] Seawater flows toward the pile foundation 1 from different directions. When the water flows into contact with the spoiler ribs 2, the spoiler ribs 2 protruding from the outer peripheral surface of the pile foundation can "break up" the water flow, locally change the flow velocity and direction of the water flow, and play a role in spoiling the flow. The energy of the water flow is dissipated to a certain extent, and it has a certain disturbing and destructive effect on the horseshoe vortex formed upstream of the pile foundation 1, preventing the formation of strong horseshoe vortex, achieving the purpose of active anti-scouring, and effectively reducing the shear stress of the seabed surface (shear stress is a reference indicator for judging the degree of scouring of the seabed surface), protecting the soil near the pile foundation 1, and avoiding the formation of scouring pits around the pile foundation 1.

[0026] In areas not covered by the spoiler ribs 2, riprap is used for protection. In some cases, the riprap layer 3 is constructed together with the spoiler ribs 2. The riprap layer 3 is located above the seabed surface 6. In this case, the riprap layer 3 acts as a barrier to the incoming flow, effectively reducing the intensity of the incoming flow and, in turn, the intensity of the scour in the downstream area. In other cases, the riprap layer 3 can also be formed by riprap in the scour pit area outside the spoiler ribs 2 after the spoiler ribs 2 have been in operation for a period of time. The riprap method can fill the scour pit and enhance the anti-scour capacity of the area, achieving a passive anti-scour effect.

[0027] The combined offshore wind power foundation anti-scour device provided by the embodiment of the present invention has an active anti-scour structure and a passive anti-scour structure, thereby combining the active and passive anti-scour effects to effectively protect the seabed within a certain range around the pile foundation. The active anti-scour structure (spoiler ribs) can effectively protect the seabed around the pile foundation and the area covered by the spoiler ribs; the passive anti-scour structure (riprap layer) can quickly and effectively protect the scour area outside the active anti-scour area. In addition, the anti-scour device provided by the embodiment of the present invention has a simple structure, is easy to install, has significant effects, and is low in cost.

[0028] Preferably, the thickness of the spoiler rib 2 is 0.01D-0.02D.

[0029] To cope with seawater flows from multiple different directions and eliminate horseshoe vortices in all directions, the spoiler ribs 2 preferably include at least four spoiler ribs 2 arranged at equal intervals around the pile foundation 1. Arranging the spoiler ribs 2 in different orientations ensures that horseshoe vortices generated from different flow directions are all disturbed and destroyed, thereby effectively protecting the bed surface around the pile foundation 1.

[0030] Preferably, the spoiler ribs 2 extend in the radial direction of the pile foundation 1 .

[0031] In some optional embodiments, the anti-scour device 100 further includes a collar 4, which is sleeved on the pile foundation 1 and connected to the pile foundation 1, and the spoiler ribs 2 are connected to the outer peripheral surface of the collar 4, that is, the spoiler ribs 2 can be connected to the pile foundation 1 through the collar 4.

[0032] In other optional embodiments, the spoiler ribs 2 may be directly welded to the outer peripheral surface of the pile foundation 1 .

[0033] In the anti-scour device 100 provided in the embodiment of the present invention, the arrangement of the spoiler ribs 2 relative to the pile foundation 1 can have various situations.

[0034] In some optional embodiments, the bottom of the spoiler rib 2 is flush with the seabed surface 6 , that is, the bottom of the spoiler rib 2 is against the seabed surface 6 .

[0035] In other optional embodiments, the bottom of the spoiler ribs 2 is buried in the seabed 5, that is, part of the spoiler ribs 2 is located below the seabed 6, and the other part is located above the seabed 6. After a period of operation, the part of the spoiler ribs 2 located below the seabed 6 gradually emerges, continuing to actively spoil the flow. This configuration avoids the phenomenon in which the relative height of the spoiler ribs 2 gradually increases as the seabed 6 slowly descends, resulting in the inability to effectively weaken the horseshoe vortex.

[0036] Alternatively, the bottom of the spoiler rib 2 can also be located above the seabed surface 6, and preferably the distance between the bottom of the spoiler rib 2 and the seabed surface 6 is less than or equal to 0.1D. This is because horseshoe vortices are generally formed near the seabed surface 6. Therefore, based on the seabed surface 6, the spoiler rib 2 is preferably located at least at a relative height of less than or equal to 0.1D meters.

[0037] The riprap layer 3 is positioned outside the area covered by the spoiler ribs 2 , ie, outside the spoiler ribs 2 . Optionally, the maximum outer diameter of the riprap layer 3 is 5D.

[0038] Optionally, the radial distance between the inner side of the riprap layer 3 and the outer end of the spoiler rib 2 in the pile foundation 1 is less than or equal to 0.01D. The outer end of the spoiler rib 2 refers to its free end away from the pile foundation 1. By making the radial distance between the inner side of the riprap layer 3 and the outer end of the spoiler rib 2 less than or equal to 0.01D in the pile foundation 1, even if the riprap layer 3 is placed as close to the spoiler rib 2 as possible, the seabed surface 6 between the riprap layer 3 and the spoiler rib 2 is not stable and scour pits can be avoided. Preferably, the inner side of the riprap layer 3 is in contact with the spoiler rib 2, so that the riprap layer 3 can more effectively protect the surrounding areas outside the coverage area of ​​the spoiler rib 2.

[0039] There are two possible implementation methods for the riprap layer 3. Alternatively, the riprap layer 3 can be constructed together with the spoiler ribs 2, with the riprap layer 3 positioned above the seabed 6, meaning its top surface is located above the seabed 6. Alternatively, the riprap layer 3 can be constructed after the spoiler ribs 2 have been in operation for a period of time, and then riprap can be added to the scour pit area outside the spoiler ribs 2, with its top surface located above or flush with the seabed 6.

[0040] Optionally, the riprap layer 3 includes sand and gravel of various particle sizes, and the median diameter of the sand and gravel ranges from 5 cm to 50 cm.

[0041] The following is based on Figure 1-Figure 4 The combined offshore wind power foundation anti-scour device 100 according to a specific embodiment of the present invention is described.

[0042] like Figure 1 and Figure 2As shown, the anti-scour device 100 includes a pile foundation 1, eight spoiler ribs 2, a riprap layer 3, and a collar 4. Figure 3 As shown, one end of each of the spoiler ribs 2 is connected to the outer circumference of the collar 4 and extends radially outward from the pile foundation 1. The spoiler ribs 2 are arranged at equal intervals around the circumference of the pile foundation 1, forming a radial pattern. As water flows toward the pile foundation 1 from different directions, it first passes through the spoiler ribs 2. These ribs disrupt and disrupt horseshoe vortices formed upstream, effectively reducing shear stress on the seabed 6. Figure 4 The figure shows the relative shear stress distribution of the seabed surface 6 around the pile foundation 1 with spoiler ribs 2 (local shear stress / local shear stress at upstream 3D). The white area in the figure indicates that the relative shear stress is less than 1, indicating that the setting of the spoiler ribs 2 can effectively reduce the shear stress in the area covered by the spoiler ribs 2, thereby achieving an anti-scouring effect.

[0043] The riprap layer 3 is located outside the spoiler ribs 2, with the top surface of the riprap layer 3 flush with the seabed surface 6. This enhances the scour resistance of the area surrounding the spoiler ribs 2, further optimizing the scour prevention effect. The anti-scour device 100 provided in this embodiment, combined with the spoiler ribs 2 and the riprap layer 3, can effectively protect the seabed within a certain range around the pile foundation 1.

[0044] 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 to 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, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore should not be understood as limiting the present invention.

[0045] Furthermore, the terms "first" and "second" are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of the technical features being referred to. Thus, a feature defined as "first" or "second" may explicitly or implicitly include at least one such feature. In the description of the present invention, "plurality" means at least two, such as two, three, etc., unless otherwise specifically defined.

[0046] In the present invention, unless otherwise specified or limited, the terms "installed," "connected," "connect," "fixed," etc. should be understood in a broad sense. For example, they can refer to fixed connection, detachable connection, or integration; mechanical connection, electrical connection, or communication; direct connection or indirect connection through an intermediate medium; internal communication between two elements or interaction between two elements, unless otherwise specified. Those skilled in the art will understand the specific meanings of the above terms in the present invention based on specific circumstances.

[0047] In the present invention, unless otherwise expressly specified or limited, when a first feature is "above" or "below" a second feature, it may mean that the first and second features are in direct contact, or that the first and second features are in indirect contact through an intermediary. Furthermore, when a first feature is "above," "above," or "above" a second feature, it may mean that the first feature is directly above or diagonally above the second feature, or simply means that the first feature is at a higher level than the second feature. When a first feature is "below," "below," or "below" a second feature, it may mean that the first feature is directly below or diagonally below the second feature, or simply means that the first feature is at a lower level than the second feature.

[0048] In the present invention, the terms "one embodiment", "some embodiments", "examples", "specific examples", or "some examples" mean that the specific features, structures, materials or characteristics described in conjunction with the embodiment or example are included in at least one embodiment or example of the present invention. In this specification, the schematic expressions of the above terms do not necessarily refer to the same embodiment or example. Moreover, the specific features, structures, materials or characteristics described can be combined in any one or more embodiments or examples in a suitable manner. In addition, those skilled in the art can combine and combine different embodiments or examples described in this specification and the features of different embodiments or examples without contradiction.

[0049] Although the embodiments of the present invention have been shown and described above, it will be understood that the above embodiments are illustrative and are not to be construed as limitations on the present invention. A person skilled in the art may change, modify, replace and modify the above embodiments within the scope of the present invention.

Claims

1. A combined offshore wind power foundation anti-scour device, characterized in that: include: a pile foundation, a portion of which is buried downwardly in the seabed; A plurality of spoiler ribs, wherein the plurality of spoiler ribs are spaced apart around the pile foundation, one end of the spoiler rib is connected to the outer peripheral surface of the pile foundation, and the other end extends away from the pile foundation, the extension length of the spoiler rib is 0.1D-0.67D, the plane on which the spoiler rib is located is perpendicular to the seabed surface, the vertical height is greater than or equal to 0.2D, and at least a portion of the spoiler rib is located above the seabed surface, where D is the outer diameter of the pile foundation; The riprap layer is located outside the spoiler ribs and is laid on the seabed around the pile foundation and the spoiler ribs.

2. The combined offshore wind power foundation anti-scour device according to claim 1, characterized in that: The spoiler ribs include at least four spoiler ribs arranged at equal intervals around the pile foundation.

3. The combined offshore wind power foundation anti-scour device according to claim 1 or 2, characterized in that: The spoiler ribs extend in a radial direction of the pile foundation.

4. The combined offshore wind power foundation anti-scour device according to claim 1 or 2, characterized in that: It also includes a collar, which is sleeved on the pile foundation and connected to the pile foundation, and the spoiler ribs are connected to the outer peripheral surface of the collar.

5. The combined offshore wind power foundation anti-scour device according to claim 1 or 2, characterized in that: The bottom of the spoiler rib is flush with the seabed surface; or, the bottom of the spoiler rib is buried in the seabed; or, the bottom of the spoiler rib is located above the seabed surface and the distance between the bottom and the seabed surface is less than or equal to 0.1D.

6. The combined offshore wind power foundation anti-scour device according to claim 1, characterized in that: The maximum outer diameter of the riprap layer is 5D.

7. The combined offshore wind power foundation anti-scour device according to claim 1 or 6, characterized in that: The top surface of the riprap layer is flush with the seabed surface or is located above the seabed surface.

8. The combined offshore wind power foundation anti-scour device according to claim 1 or 6, characterized in that: The riprap layer includes sand and gravel of various particle sizes, and the median diameter of the sand and gravel ranges from 5 cm to 50 cm.

9. The combined offshore wind power foundation anti-scour device according to claim 1, characterized in that: The thickness of the spoiler rib is 0.01D-0.02D.

10. The combined offshore wind power foundation anti-scour device according to claim 1, characterized in that: The distance between the inner side of the riprap layer and the outer end of the spoiler rib in the radial direction of the pile foundation is less than or equal to 0.01D.

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