CN113718827A

CN113718827A - Offshore wind power foundation with energy dissipation structure

Info

Publication number: CN113718827A
Application number: CN202111087576.2A
Authority: CN
Inventors: 邱旭; 闫姝; 张波
Original assignee: Huaneng Clean Energy Research Institute
Current assignee: Huaneng Clean Energy Research Institute
Priority date: 2021-09-16
Filing date: 2021-09-16
Publication date: 2021-11-30

Abstract

The invention discloses an offshore wind power foundation with an energy dissipation structure, which comprises a pile foundation, wherein the pile foundation comprises a first part and a second part which are mutually connected in the axial direction of the pile foundation, the second part is buried in a seabed, the seabed is provided with a seabed surface, the first part is positioned above the seabed surface, the outer peripheral surface of the first part comprises a front surface facing to a tide direction, a back surface opposite to the front surface and two side surfaces, the energy dissipation structure comprises energy dissipation pieces protruding from the outer peripheral surface of the first part and/or energy dissipation holes penetrating through the peripheral wall of the first part, and the energy dissipation structure comprises first energy dissipation structures arranged on the front surface and the back surface. The offshore wind power foundation has the advantages of simple structure, low cost, tidal current dissipation and the like.

Description

Offshore wind power foundation with energy dissipation structure

Technical Field

The application relates to the technical field of new energy, in particular to an offshore wind power foundation with an energy dissipation structure.

Background

Wind energy is increasingly regarded by human beings as a clean and harmless renewable energy source. Compared with land wind energy, offshore wind energy resources not only have higher wind speed, but also are far away from a coastline, are not influenced by a noise limit value, and allow the unit to be manufactured in a larger scale.

In the related technology, the offshore wind power foundation is the key point for supporting the whole offshore wind power machine, the cost accounts for 20-25% of the investment of the whole offshore wind power, and most accidents of offshore wind power generators are caused by unstable pile foundation. Due to the action of waves and tide, silt around the offshore wind power pile foundation can be flushed and form a flushing pit, and the flushing pit can influence the stability of the pile foundation. In addition, the water flow mixed with silt near the surface of the seabed continuously washes the pile foundation, corrodes and destroys the surface of the pile foundation, and can cause the collapse of the offshore wind turbine unit in serious cases. The anti-scouring device of the currently adopted offshore wind power pile foundation is mainly a riprap protection method. However, the integrity of the riprap protection is poor, and the maintenance cost and the workload in the application process are large.

Disclosure of Invention

The present invention is based on the discovery and recognition by the inventors of the following facts and problems:

due to the action of sea waves and tides, a phenomenon of scouring pits occurs around the foundation of the offshore wind power pile. The scouring phenomenon is a complex coupling process involving the interaction of water flow, sediment and structures. The main reason of causing the scouring is horseshoe-shaped vortex generated around the pile foundation, the horseshoe-shaped vortex is generated due to the obstruction of the pile foundation when seawater flows, when the sea water flows towards the pile foundation, the wave current presents a downward rolling and excavating vortex structure, the vortex structure lifts up the sediment on the seabed, and further brings the sediment away from the place around the pile foundation, a scouring pit is formed, the depth of the pile foundation is shallow due to the formation of the scouring pit, the vibration frequency of a cylinder is reduced, the pile foundation is over-fatigue is caused slightly, and the fracture accident is caused seriously.

The present application is directed to solving, at least to some extent, one of the technical problems in the related art. Therefore, the offshore wind power foundation has the advantages that the effect of dissipating tidal current energy is achieved, the purpose of active scour prevention is achieved, soil around the pile foundation is effectively protected, and a scour pit is avoided.

The offshore wind power foundation with an energy dissipation structure according to the present invention comprises: a pile foundation including a first portion and a second portion connected to each other in an axial direction thereof, the second portion being buried in a seabed having a seabed surface above which the first portion is located, an outer circumferential surface of the first portion including a front surface facing in a direction of tidal current, a back surface opposite to the front surface, and two side surfaces, an energy dissipating structure including energy dissipating members protruding from an outer circumferential surface of the first portion and/or energy dissipating holes penetrating a circumferential wall of the first portion, the energy dissipating structure including first energy dissipating structures provided on the front surface and the back surface.

According to the offshore wind power foundation provided by the embodiment of the invention, the first energy dissipation structures are arranged on the front surface and the back surface, so that a rapid flow or a main flow in seawater is converted into a uniform slow flow, the impact of the seawater on the surface of the pile foundation is reduced, the formation of horseshoe-shaped vortex is inhibited, and the offshore wind power foundation has good erosion resistance.

In some embodiments, the energy dissipaters include one or more of energy dissipater pins, energy dissipater strips and energy dissipater nets, wherein the energy dissipater pins include a plurality of pins and are arranged on the outer peripheral surface of the first part at intervals, the ratio of the dimension of the energy dissipater pins in the length direction of the pile foundation to the dimension of the energy dissipater pins in the circumferential direction around the pile foundation is greater than or equal to 1/2 and less than or equal to 2, the extending direction of the energy dissipater strips is parallel to the outer peripheral surface of the first part, the ratio of the length to the width of the energy dissipater strips is greater than or equal to 5, and the energy dissipater nets are net structures covering at least a part of the outer peripheral surface of the first part.

In some embodiments, the energy dissipaters further comprise second energy dissipaters disposed on the two side faces.

In some embodiments, the first energy dissipaters are of a different type to the second energy dissipaters.

In some embodiments, the first energy dissipating structure is the energy dissipating strip and the second energy dissipating structure is the energy dissipating nail.

In some embodiments, the energy dissipater strip extends in the axial direction of the pile foundation, and the energy dissipater strip comprises a plurality of energy dissipater strips arranged at intervals in the circumferential direction around the pile foundation.

In some embodiments, the energy dissipation strips are arc-shaped and extend along the circumferential direction around the pile foundation, and the energy dissipation strips are arranged at intervals in the axial direction of the pile foundation.

In some embodiments, the spacing of the dissipaters decreases towards the surface of the seabed.

In some embodiments, the density of the energy dissipating nails increases towards the surface of the seabed.

In some embodiments, the first energy dissipating structure is an energy dissipating mesh and the second energy dissipating structure is an energy dissipating strip, or the first energy dissipating structure is an energy dissipating mesh and the second energy dissipating structure is an energy dissipating nail.

Drawings

Fig. 1 is a schematic structural diagram of an offshore wind power foundation according to a first embodiment of the invention.

Fig. 2 is a schematic structural diagram of an offshore wind power foundation according to a second embodiment of the invention.

Reference numerals:

an offshore wind power foundation 100;

pile foundations 1; a first portion 11; a second portion 12; an energy dissipation structure 2; a first energy dissipating structure 21; a second energy dissipating structure 22.

Detailed Description

Reference will now be made in detail to embodiments of the present invention, examples of which are illustrated in the accompanying drawings. The embodiments described below with reference to the drawings are illustrative and intended to be illustrative of the invention and are not to be construed as limiting the invention.

An offshore wind farm according to an embodiment of the invention is described below with reference to fig. 1-2.

As shown in fig. 1, an offshore wind power foundation according to an embodiment of the present invention includes a pile foundation 1 and an energy dissipation structure 2.

The pile foundation 1 comprises a first part 11 and a second part 12 connected to each other in its axial direction, the second part 12 being buried in the seabed, the seabed having a seabed surface, the first part 11 being located above the seabed surface, the outer circumferential surface of the first part 11 comprising a front side facing the direction of the tide, a rear side opposite the front side and two side faces.

Specifically, the pile foundation 1 is a hollow cylindrical structure, and the sea bed surface is the interface of seawater and underwater sand. A first part 11 and a second part 12 connected to each other are provided in order in the up-down direction of the pile foundation 1. The first part 11 of the pile foundation 1 is located in the sea water above the surface of the sea bed and the second part 12 of the pile foundation 1 is buried in the sand below the surface of the sea bed. And defines the outer periphery of the first part 11 as a front facing the direction of the flow, as a side facing away from the direction of the flow, and as a side connecting the front and the back (e.g., the flow is east-west flowing, and flows in north-south flow rarely occur. the east of the first part 11 is the front and the west of the first part 11 is the back, or the west of the first part 11 is the front, the east of the first part 11 is the back, and the north-south of the first part 11 are the sides)

The dissipater 2 comprises dissipaters protruding from the outer periphery of the first part 11 and/or dissipater holes extending through the peripheral wall of the first part 11, the dissipater 2 comprising first dissipaters 21 provided on the front and back faces.

Specifically, the energy dissipation structure 2 can be arranged in various ways, including but not limited to, the energy dissipation structure 2 can be an energy dissipation member arranged on the outer peripheral surface of the first part 11 and extending outward in the inward and outward directions, or the energy dissipation structure 2 can be an energy dissipation hole penetrating through the outer peripheral surface of the first part 11, or the energy dissipation structure 2 can be an energy dissipation member or a combination of energy dissipation holes arranged on the outer peripheral surface of the first part 11.

According to the offshore wind power foundation 100 provided by the embodiment of the invention, the first energy dissipation structures 21 are arranged on the front surface and the back surface, so that the first energy dissipation structures 21 actively disturb the tidal current, the flow speed and the direction of the tidal current are locally changed, the energy of the tidal current is dissipated to a certain extent, the first energy dissipation structures 21 play a role in energy dissipation and impact reduction, the formation of horseshoe-shaped vortexes near the pile foundation 1 is inhibited, the soil around the pile foundation 1 is effectively protected, and the formation of scouring pits is avoided. When the tide contacts the first energy dissipation structure 21, the first energy dissipation structure 21 can 'break up' the tide, the flow speed and the direction of the tide are locally changed, the energy of the tide is dissipated to a certain extent, and a large horseshoe-shaped vortex cannot be generated in front of the pile foundation 1, so that the formation of the horseshoe-shaped vortex is restrained at the source.

The energy dissipation member comprises one or more of energy dissipation nails, energy dissipation strips and energy dissipation nets (not shown in the figures), wherein the energy dissipation nails comprise a plurality of energy dissipation nails which are arranged on the outer peripheral surface of the first part 11 at intervals, the ratio of the dimension of the energy dissipation nails in the length direction (up and down direction as shown in figures 1-2) of the pile foundation 1 to the dimension of the energy dissipation nails in the circumferential direction around the pile foundation 1 is greater than or equal to 1/2 and less than or equal to 2, the extension direction of the energy dissipation strips is parallel to the outer peripheral surface of the first part 11, the ratio of the length to the width of the energy dissipation strips is greater than or equal to 5, and the energy dissipation nets are net-shaped structures covering at least one part of the outer peripheral surface of the first part 11.

Specifically, as shown in fig. 1, the energy dissipation pins are arranged on the outer peripheral side of the first portion 11 at intervals in the circumferential direction of the first portion 11, the dimension of the turbulence pins in the vertical direction is the length L1 of the turbulence pins, the dimension of the turbulence pins in the circumferential direction of the pile foundation 1 is the width M1 of the turbulence pins, L1 is 0.5 times to 2 times of M1, for example, L1 may be 0.5 times, 1 time, 1.5 times, 1.8 times, 2 times, etc. of M1. The energy dissipation strips surround the outer periphery of the first part 11, the surrounding length of the energy dissipation strips is L2, the dimension of the energy dissipation strips in the vertical direction is M2, the ratio of L2 to M2 is more than 5, and for example, L2 can be 5 times, 6 times, 6.5 times, 7 times, 7.5 times, etc. of M2. The energy dissipation net is a net structure which is arranged around the periphery of the first part 11. The energy dissipation piece includes but not limited to any kind such as energy dissipation nail, energy dissipation strip and energy dissipation net, or any combination form of energy dissipation nail, energy dissipation strip and energy dissipation net, from this, can choose different energy dissipation pieces for use according to the waters of difference, more effectual carries out the vortex to the trend, realizes the diversification of marine wind power basis 100.

In the related art, the offshore wind power foundation 100 is arranged in a shallow water area where the current mainly approaches the coastline or moves away from the coastline in a direction approximately perpendicular to the coastline at the time of tide rise and tide fall, so that the side of the pile foundation 1 facing the coastline and the side facing away from the coastline are where the current mainly impacts. In the two places of the pile foundation 1, the impact force of the borne tide is larger, and the number of the scouring pits caused by the vortex is larger. The extending direction of the other two side surfaces of the pile foundation 1 is consistent with the tide direction, and the tide mainly has friction and smaller impact force on the other two side surfaces of the pile foundation 1. Thus, in some embodiments, the dissipater 2 also includes a second dissipater 22 provided on both sides. Specifically, the second energy dissipation structures 22 are arranged on two side surfaces of the first part 11, so that friction and impact of tide on the pile foundation 1 can be resisted through the second energy dissipation structures 22, the energy dissipation efficiency of the energy dissipation structures 2 is improved, and the service life of the pile foundation 1 is prolonged.

Because the front surface and the back surface are subjected to larger tide impact, the two side surfaces are subjected to smaller tide impact. Thus, in view of economic efficiency, in some embodiments, the first energy dissipaters 21 are of a different type to the second energy dissipaters 22. Specifically, the first energy dissipation structure 21 is one of an energy dissipation nail, an energy dissipation strip, and an energy dissipation mesh, and the second energy dissipation structure 22 is another one of the energy dissipation nail, the energy dissipation strip, and the energy dissipation mesh. Thereby, the types of the first energy dissipation structure 21 and the second energy dissipation structure 22 are set according to actual conditions, so that the cost of the energy dissipation structure 2 is reduced, and the setting of the energy dissipation structure 2 is more reasonable.

In some embodiments, the first energy dissipating structures 21 are energy dissipating strips and the second energy dissipating structures 22 are energy dissipating nails. Specifically, as shown in fig. 1, the front and back of the first part 11 are provided with energy dissipation strips, and two sides of the first part 11 are provided with energy dissipation nails, so that the cost of the energy dissipation structure 2 is reduced, and the energy dissipation structure 2 is more reasonable to set.

The energy dissipation strips extend along the axial direction (the up-down direction as shown in fig. 1) of the pile foundation 1, and the energy dissipation strips comprise a plurality of energy dissipation strips which are arranged at intervals in the circumferential direction around the pile foundation 1. Specifically, as shown in fig. 1, a plurality of energy dissipation strips are arranged on the front surface and the back surface of the first part 11, the plurality of energy dissipation strips are arranged at intervals around the circumference of the first part 11, a plurality of energy dissipation channels which are arranged along the circumference of the first part 11 and are mutually spaced and parallel to the vertical direction are formed by the plurality of energy dissipation strips, the energy dissipation channels among the plurality of energy dissipation strips are used for scattering the tidal current, the flow speed and the direction of the tidal current are locally changed, the energy of the tidal current is dissipated to a certain extent, a large horseshoe-shaped vortex cannot be generated in front of the first part 11, and the formation of the horseshoe-shaped vortex is restrained at the source.

The energy dissipation strip is the arc and extends along the circumference that encircles pile foundation 1, and the energy dissipation strip is a plurality of, and a plurality of energy dissipation strips are arranged at interval in the axial (as shown in figure 2, upper and lower direction) of pile foundation 1. Specifically, as shown in fig. 2, at the front and back surfaces of the first part 11, the energy dissipation strips surround the first part 11, and a plurality of energy dissipation strips are arranged at intervals in the up-down direction.

It should be noted that the energy dissipation strips can be in the shape of the peripheral profile of the cross section, including one or more of a semicircle, a triangle or a square, and the flexibility of the whole scheme is greatly improved by utilizing the combination of the energy dissipation strips with various different structural shapes.

During the actual use of the offshore wind power foundation 100, the closer the position on the first section 11 to the surface of the sea bed is, the greater the impact of the tidal current, and the greater the possibility of generating horseshoe vortices. Thus, in some embodiments, the spacing of the dissipaters decreases towards the surface of the seabed. Specifically, the arrangement distance of the energy dissipation strips is gradually reduced from top to bottom on the front side and the back side of the first part 11, the number of the energy dissipation strips at the bottom of the first part 11 is increased, the anti-scouring capability of the front side and the back side of the first part 11 is improved, and the anti-scouring capability and the practicability of the offshore wind power foundation 100 are enhanced.

The density of the energy dissipation nails is increased towards the direction close to the surface of the seabed. Specifically, the number of the energy dissipation nails gradually increases from top to bottom on both sides of the first portion 11, so that the erosion resistance of both sides of the first portion 11 is improved, and the erosion resistance and the practicability of the offshore wind power foundation 100 are further enhanced.

In some embodiments, the first energy dissipation structure 21 is an energy dissipation net (not shown) and the second energy dissipation structure 22 is an energy dissipation strip, or the first energy dissipation structure 21 is an energy dissipation net and the second energy dissipation structure 22 is an energy dissipation nail. Specifically, the front and the back of the first part 11 are provided with energy dissipation nets, and two side surfaces of the first part 11 are provided with energy dissipation strips or energy dissipation nails, so that the cost of the energy dissipation structure 2 is reduced, and the energy dissipation structure 2 is more reasonable in arrangement.

In the description of the present invention, it is to be understood that the terms "central," "longitudinal," "lateral," "length," "width," "thickness," "upper," "lower," "front," "rear," "left," "right," "vertical," "horizontal," "top," "bottom," "inner," "outer," "clockwise," "counterclockwise," "axial," "radial," "circumferential," and the like are used in the orientations and positional relationships indicated in the drawings for convenience in describing the invention and to simplify the description, and are not intended to indicate or imply that the referenced devices or elements must have a particular orientation, be constructed and operated in a particular orientation, and are therefore not to be considered limiting of the invention.

Furthermore, the terms "first", "second" and "first" are used for descriptive purposes only and are not to be construed as indicating or implying relative importance or implicitly indicating the number of technical features indicated. 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, "a plurality" means at least two, e.g., two, three, etc., unless specifically limited otherwise.

In the present invention, unless otherwise expressly stated or limited, the terms "mounted," "connected," "secured," and the like are to be construed broadly and can, for example, be fixedly connected, detachably connected, or integrally formed; may be mechanically coupled, may be electrically coupled or may be in communication with each other; they may be directly connected or indirectly connected through intervening media, or they may be connected internally or in any other suitable relationship, unless expressly stated otherwise. The specific meanings of the above terms in the present invention can be understood by those skilled in the art according to specific situations.

In the present invention, unless otherwise expressly stated or limited, the first feature "on" or "under" the second feature may be directly contacting the first and second features or indirectly contacting the first and second features through an intermediate. Also, a first feature "on," "over," and "above" a second feature may be directly or diagonally above the second feature, or may simply indicate that the first feature is at a higher level than the second feature. A first feature being "under," "below," and "beneath" a second feature may be directly under or obliquely under the first feature, or may simply mean that the first feature is at a lesser elevation than the second feature.

In the present disclosure, the terms "one embodiment," "some embodiments," "an example," "a specific example," or "some examples" and the like mean that a specific feature, structure, material, or characteristic described in connection with the embodiment or example is included in at least one embodiment or example of the present disclosure. In this specification, the schematic representations of the terms used above are not necessarily intended to refer to the same embodiment or example. Furthermore, the particular features, structures, materials, or characteristics described may be combined in any suitable manner in any one or more embodiments or examples. Furthermore, various embodiments or examples and features of different embodiments or examples described in this specification can be combined and combined by one skilled in the art without contradiction.

Although embodiments of the present invention have been shown and described above, it is understood that the above embodiments are exemplary and should not be construed as limiting the present invention, and that variations, modifications, substitutions and alterations can be made to the above embodiments by those of ordinary skill in the art within the scope of the present invention.

Claims

1. An offshore wind power foundation with an energy dissipation structure, comprising:

a pile foundation including a first portion and a second portion connected to each other in an axial direction thereof, the second portion being buried in a seabed having a seabed surface over which the first portion is located, an outer circumferential surface of the first portion including a front surface facing a tidal current direction, a back surface opposite the front surface, and two side surfaces,

energy dissipaters comprising energy dissipaters protruding from the outer peripheral surface of the first part and/or energy dissipater holes extending through the peripheral wall of the first part, the energy dissipaters comprising first energy dissipaters provided on the front and back faces.

2. An offshore wind farm with energy dissipation structures according to claim 1, characterized in that the energy dissipaters comprise one or more of energy dissipation nails, energy dissipation strips and energy dissipation meshes,

the energy dissipation nails are arranged on the outer peripheral surface of the first part at intervals, the ratio of the dimension of the energy dissipation nails in the length direction of the pile foundation to the dimension of the energy dissipation nails in the circumferential direction surrounding the pile foundation is greater than or equal to 1/2 and less than or equal to 2, the extension direction of the energy dissipation strips is parallel to the outer peripheral surface of the first part, the ratio of the length to the width of the energy dissipation strips is greater than or equal to 5, and the energy dissipation net is a net-shaped structure covering at least one part of the outer peripheral surface of the first part.

3. An offshore wind energy foundation with energy dissipaters according to claim 2, characterised in that the energy dissipaters further comprise second energy dissipaters provided on the two sides.

4. Offshore wind energy foundation with energy dissipations according to claim 3, characterized in that said first energy dissipations are of a different type than said second energy dissipations.

5. An offshore wind power foundation with energy dissipation structures as claimed in claim 4, wherein the first energy dissipation structure is the energy dissipation strip and the second energy dissipation structure is the energy dissipation nail.

6. An offshore wind power foundation with an energy dissipation structure as claimed in claim 5, wherein the energy dissipation strips extend in the axial direction of the pile foundation and comprise a plurality of strips spaced circumferentially around the pile foundation.

7. The offshore wind power foundation with an energy dissipation structure of claim 5, wherein the energy dissipation strips are arc-shaped and extend in a circumferential direction around the pile foundation, and the energy dissipation strips are arranged in plurality at intervals in an axial direction of the pile foundation.

8. An offshore wind energy foundation with energy dissipation structure according to claim 7, characterized in that the spacing of the energy dissipation strips decreases towards the surface of the sea bed.

9. An offshore wind energy foundation with energy dissipation structures according to any one of claims 5 to 8, wherein the density of the energy dissipation nails increases towards the surface of the seabed.

10. An offshore wind energy foundation with energy dissipations according to claim 3, characterised in that the first energy dissipations are energy dissipater meshes and the second energy dissipations are energy dissipater strips,

or the first energy dissipation structure is an energy dissipation net, and the second energy dissipation structure is an energy dissipation nail.