A broadband energy-harvesting and wave-dissipating wave energy utilization type open breakwater and its design method

Abstract

The present invention discloses a wave energy utilization type open breakwater with wide-band energy capture and wave dissipation and its design method, belonging to the field of breakwater design. The open breakwater includes a wave energy conversion system and a bottom pile foundation support structure; the wave energy conversion system is composed of oscillating water column wave energy conversion units, and each oscillating water column wave energy conversion unit includes a front air chamber, a rear air chamber, a transverse water channel, an air turbine and a control room; based on the transverse water channel structure, the present invention conducts a resonance period complementary design to achieve wide-band wave energy capture, and further achieve wide-band wave protection performance, focusing on breaking through the problem of wave energy dissipation of the open breakwater for longer-period waves. In addition, the present invention dissipates waves in the way of wave energy capture, can generate renewable electricity while dissipating incident waves in a wide frequency band, and adopts a pile-supported open foundation, allowing water exchange inside and outside the port area, with remarkable environmental friendliness, and is a green breakwater with great development prospects.

Description

Technical Field

[0001] The present invention belongs to the field of breakwater design, and particularly relates to a wave energy utilization type open - type breakwater with broadband energy capture and wave dissipation and its design method. Background Art

[0002] Wave energy is a high - quality and important clean and renewable energy source, which has the advantages of high energy grade, large total reserves, high energy flux density, wide distribution range, etc. It is regarded as a strategic resource by major marine countries in the world to solve energy shortage, protect the ecological environment and respond to climate change.

[0003] The technology of wave energy power generation has a history of more than a hundred years, and there are thousands of patents on wave energy power generation technology. The forms of power generation devices are diverse. According to different working principles, they can be mainly divided into three types: oscillating water column type, concentrating wave over - topping type and oscillating body type. The biggest difference between the oscillating water column type device and other wave energy conversion devices is that its main structure is an air chamber. Waves excite the water column oscillation in the air chamber, drive the air in the air chamber to generate reciprocating air flow, and push the air turbine to rotate and then drive the generator to generate electricity. The oscillating water column type device has the advantages of simple structure, few moving components, good durability, high reliability and wide application range. It is currently the wave energy conversion device with the most research and the best progress.

[0004] Currently, the main problems that plague the development of oscillating water column type devices are the problems of high efficiency and economy: First, the wave energy capture efficiency of the oscillating water column device is not ideal enough, and the high - efficiency capture frequency band is relatively narrow. When the wave frequency is far from the resonance frequency band of the oscillating water column, the wave energy capture frequency drops sharply; Second, the volume required for the air chamber structure is generally large, the infrastructure cost is generally high, and the investment return ratio is relatively low.

[0005] Waves are one of the most important marine dynamic factors. Traditional rubble - mound breakwaters, vertical breakwaters or composite breakwaters can defend against wave attacks and provide a stable water area and safe berthing and operation conditions for port areas. However, with the development of the marine economy, the development and utilization of the ocean gradually move towards deep water, and at the same time, humans pay more and more attention to marine environmental protection. Traditional breakwaters can no longer fully meet the development needs. As a new type of "green" breakwater applicable to deeper water depths, the open - type breakwater utilizes the characteristic that the main energy of waves is concentrated in the water surface layer. It has the advantages that the project cost is not sensitive to water depth and the water body exchange performance is good, and it has received more and more attention and emphasis from the domestic and foreign coastal and offshore engineering circles, and has broad application prospects. However, at present, the wave protection performance of the open - type breakwater is still not ideal when facing medium - to - long - period waves, and it is urgent to explore the advantageous open - type breakwater configuration.

[0006] Integrating an oscillating water column device with a breakwater for complementary functions and cost sharing is a highly promising win-win development strategy: the oscillating water column device captures wave energy and reduces waves, with wave energy utilization being compatible with wave protection functions; wave protection sites usually have large waves, i.e., rich wave energy resources, and the working conditions are compatible; sharing marine infrastructure helps reduce investment costs and improve economic efficiency; using marine energy to generate electricity locally helps with the sustainable development of marine resources. Summary of the Invention

[0007] To solve the problems in the prior art, the present invention proposes a wave energy utilization type open - type breakwater with broadband energy capture and wave dissipation and its design method. The present invention focuses on the common problems of open - type oscillating water column devices and open - type breakwaters, namely, the narrow bandwidth of efficient operation and poor effect on low - frequency waves. Based on the lateral water channel structure, a resonance period complementary design is carried out to achieve broadband wave energy capture, and then broadband wave protection performance is realized, with a key breakthrough in the problem of wave energy dissipation of open - type breakwaters for longer - period waves. In addition, the present invention dissipates waves by capturing wave energy, can generate renewable electricity while dissipating incident waves in a broadband, and adopts a pile - foundation open - type foundation, allowing water exchange inside and outside the port area, with significant environmental friendliness, and is a green breakwater with great development prospects.

[0008] The technical solution of the present invention is as follows:

[0009] The present invention provides a wave energy utilization type open - type breakwater with broadband energy capture and wave dissipation, which includes a wave energy conversion system and a bottom pile - foundation support structure; the wave energy conversion system is composed of oscillating water column wave energy conversion units, and the oscillating water column wave energy conversion unit includes a front air chamber, a rear air chamber, a lateral water channel, an air turbine, and a control room;

[0010] The front air chamber is enclosed by an air chamber front wall, a control room front wall, and a device top plate, and is located on the wave - facing side inside the wave energy conversion unit; the rear air chamber is enclosed by an air chamber rear wall, a control room rear wall, and a device top plate, and is located on the wave - sheltered side inside the wave energy conversion unit; the lateral water channel is enclosed by a control room bottom plate and a device bottom plate; the lateral water channel is respectively connected to the front air chamber and the rear air chamber, and a spacing is provided between the bottom of the air chamber front wall and the device bottom plate as a communication opening between the lateral water channel and the external environment; air turbines are provided at the tops of both the front air chamber and the rear air chamber, and the front air chamber and the rear air chamber are connected to the external air through the air turbines, and the control room is enclosed by a control room front wall, a control room rear wall, a control room bottom plate, and a device top plate;

[0011] The bottom pile - foundation support structure includes a pile foundation and a top panel. Among them, the pile foundation on the wave - facing side adopts a combination of vertical piles and single - inclined piles, and the pile foundation on the wave - sheltered side adopts a combination of double - inclined piles. The pile foundation is connected to the top panel through a pile cap; the device bottom plate is installed on the top panel.

[0012] Preferably, both the front air chamber and the rear air chamber are vertically arranged square air chambers. The transverse water channel communicates with the rear air chamber to form an L-shaped oscillating water column device. The size of the front air chamber is designed such that the resonance period of the front oscillating water column device formed therein corresponds to high-frequency waves, and the size of the transverse water channel and the rear air chamber is designed such that the resonance period of the L-shaped oscillating water column device corresponds to low-frequency waves. After the wave energy conversion performances of the front and rear oscillating water column devices are superimposed, the resonance period of the oscillating water column wave energy conversion unit is made equal to the annual average wave period T of the target sea area.

[0013] Preferably, circular nozzles are opened in the device roof plate areas at the tops of both the front air chamber and the rear air chamber. An air turbine is installed in the circular nozzles. The air turbine is used to convert the air kinetic energy into the mechanical energy of its own rotation under the push of the reciprocating air flow excited by the oscillating water column, and then drive a generator to generate electricity.

[0014] Preferably, an air turbine control system is equipped in the control room; the air turbine control system has a built-in correspondence between the optimal rotational speed and wave parameters, and the wave parameters are wave height and wave period. The air turbine control system adjusts the rotational speeds of the air turbines of the front air chamber and the rear air chamber according to the incident wave parameters to achieve efficient wave energy capture.

[0015] Preferably, an energy storage unit is equipped in the control room. The energy storage unit can be a battery device for storing the electric energy obtained by the air turbine.

[0016] Preferably, the bottom plate of the control room is thickened. While protecting the control room, it increases the self-weight of the upper structure of the breakwater and enhances the stability; the rear wall of the air chamber is in a triangular configuration, narrow at the top and wide at the bottom. The front end face of the rear wall of the air chamber is a vertical plane. The triangular configuration effectively resists the overturning moment brought by the wave load and enhances the structural stability.

[0017] The present invention also provides a broadband energy capture and wave dissipation design method for the open breakwater, which includes the following steps:

[0018] S1. Collect the wave conditions and tide levels of the actual deployment sea area, and analyze to obtain the annual average wave period T and the designed low water level in the sea area;

[0019] S2. Set the elevation of the bottom of the front wall of the air chamber to be 1.0 m lower than the designed low water level, and at the same time, the elevation of the bottom of the control room floor is not higher than the elevation of the bottom of the front wall of the air chamber to facilitate the capture of wave energy by the front air chamber;

[0020] S3. Determine the size of the oscillating water column wave energy conversion unit through physical model experiments or numerical simulation calculations. Among them, the size design should make the resonance period ratio of the front oscillating water column device smaller than T to convert the energy of shorter periods; the resonance period ratio of the rear oscillating water column device larger than T to convert the energy of longer periods; and after the conversion performance of the front and rear oscillating water column devices is superimposed, the resonance period of the oscillating water column wave energy conversion unit is equal to T to achieve broadband and efficient conversion of the wave energy in the target sea area, thereby achieving wave energy reduction.

[0021] S4. Under the condition that the size of the oscillating water column wave energy conversion unit is determined, obtain the optimal rotational speeds of the air turbines in the front and rear air chambers under different wave parameters through experiments and store them in the air turbine control system.

[0022] In the above-mentioned S3, the size of the oscillating water column wave energy conversion unit includes the size of the front oscillating water column device and the size of the rear oscillating water column device. Among them, the size of the front oscillating water column device includes: the width of the front air chamber, the draft depth of the front wall of the air chamber, and the draft depth of the front wall of the control chamber; the size of the rear oscillating water column device includes: the width of the rear air chamber, the draft depth of the rear wall of the control chamber, the height of the transverse water channel, and the width of the transverse water channel.

[0023] Compared with the prior art, the beneficial effects of the present invention include:

[0024] Through the novel transverse water channel design, the natural frequencies of the front and rear oscillating water columns respectively correspond to high- and low-frequency waves, enabling the device to have excellent wave energy conversion performance in a relatively wide frequency band; the transverse water channel structure can also serve as a connection channel between the front and rear air chambers. Based on the wave diffraction characteristics, it gives full play to the coherent effect between the air chambers, enhancing the wave energy capture performance of the overall device, and thus enhancing wave reduction.

[0025] The control room of the present invention is equipped with an air turbine control system; the air turbine control system has a built-in correspondence between the optimal rotational speed and wave parameters. The wave parameters are specifically the correspondence between wave height and wave period. The air turbine control system adjusts the rated rotational speeds of the air turbines in the front and rear air chambers according to the incident wave conditions based on the incident wave parameters to achieve efficient wave energy capture.

[0026] The overall device of the present invention has strong economic efficiency: by integrating the oscillating water column system with a permeable breakwater, reducing waves in the form of wave energy capture, and sharing construction space, resources, and infrastructure, it realizes functional complementarity and cost sharing.

[0027] The overall device of the present invention has strong environmental friendliness: the permeable structure can meet the exchange of internal and external water bodies. At the same time, wave energy conversion is green and low-carbon, and systematic and large-scale power generation can contribute to its own and the surrounding industrial energy supply systems.

[0028] In summary, the present invention integrates a highly reliable oscillating water column device with a perforated breakwater, taking into account wave energy capture and wave protection performance, and meeting the exchange requirements of internal and external water bodies. It is a green breakwater with great development prospects. BRIEF DESCRIPTION OF THE DRAWINGS

[0029] Figure 1 is a schematic diagram of the overall structure of the present invention;

[0030] Figure 2 is an axonometric view of the structure after the actual construction of the present invention is completed;

[0031] Figure 3 is the cross-sectional dimension of the experimental model;

[0032] Figure 4 is the curve of the wave-gas conversion efficiency of each model varying with the wave period;

[0033] Figure 5 is the curve of the transmission coefficient varying with the wave period. DETAILED DESCRIPTION OF THE EMBODIMENTS

[0034] The present invention will be further described and explained below in conjunction with the specific embodiments. The embodiments are only examples of the present disclosure and do not delimit the scope of limitation. The technical features of each embodiment of the present invention can be combined accordingly without conflict.

[0035] As Figure 1 shown, it is a specific structural example of a wave energy utilization type perforated breakwater for wideband energy capture and wave dissipation proposed by the present invention, which mainly includes a wave energy conversion system and a bottom pile foundation support structure; the wave energy conversion system is composed of oscillating water column wave energy conversion units, and each wave energy conversion unit is composed of a front air chamber 1, a rear air chamber 2, a transverse water channel 3, an air turbine 4, and a control room 5. The front air chamber is surrounded by a front wall 6 of the air chamber, a front wall 7 of the control room, and a top plate 8 of the device, and is located on the wave-facing side inside the breakwater; the rear air chamber is surrounded by a rear wall 9 of the air chamber, a rear wall 10 of the control room, and a top plate 8 of the device, and is located on the wave-back side inside the breakwater; the transverse water channel is composed of a bottom plate 11 of the control room and a bottom plate 12 of the device; the control room is composed of a front wall 7 of the control room, a rear wall 10 of the control room, a bottom plate 12 of the control room, and a top plate 8 of the device; the bottom pile foundation support structure includes a pile foundation and a top panel 13. The pile foundation 14 on the wave-facing side adopts a combination of vertical piles and single inclined piles, and the pile foundation 15 on the wave-back side adopts a combination of double inclined piles. The pile foundation is connected to the top panel 13 through a pile cap 16. The wave energy conversion unit is fixedly installed on the top panel 13 through the bottom plate 12 of the device.

[0036] First, it is necessary to conduct a detailed investigation and collect data such as the wave conditions and tidal levels in the actual deployment sea area. The wave conditions can be calculated through the measured data of wave buoys or numerical software such as Mike21, and the tidal level data can be obtained from tidal level stations. Analyze to obtain the annual average wave period T in the sea area, as well as the design low water level, etc.

[0037] Secondly, in order to allow more energy to enter the entire double-chamber system, the draft of the front wall 6 of the air chamber should be as small as possible. Set its bottom elevation 1.0 m lower than the design low water level. At the same time, the bottom elevation of the control room floor 11 should not be higher than the bottom elevation of the front wall 6 of the air chamber to facilitate the front air chamber to capture wave energy.

[0038] Furthermore, the size of the oscillating water column wave energy conversion unit needs to be determined through physical model experiments or numerical simulation calculations. The size design should make the resonance period of the front oscillating water column device slightly smaller than T to convert the energy of shorter periods; the resonance period of the rear oscillating water column device should be slightly larger than T to convert the energy of longer periods; after the conversion performances of the two devices are superimposed, make the resonance period of the oscillating water column wave energy conversion unit equal to T to achieve wide-band and high-efficiency conversion of wave energy in the target sea area:

[0039] Specifically, the front air chamber is composed of the front wall 6 of the air chamber, the front wall 7 of the control room, and the device top plate 8. To control the resonance period of the front oscillating water column device, the specific dimensions that need to be designed include: the width of the front air chamber (the horizontal distance between the front wall 6 of the air chamber and the front wall 7 of the control room), the draft of the front wall 6 of the air chamber (the longitudinal distance from the bottom of the front wall 6 of the air chamber to the still water surface), and the draft of the front wall 7 of the control room (the longitudinal distance from the bottom of the front wall 7 of the control room to the still water surface), so that.

[0040] Specifically, the rear air chamber is composed of the rear wall 9 of the air chamber, the rear wall 10 of the control room, and the device top plate 8. The horizontal water channel is composed of the device bottom plate 12 and the control room bottom plate 11. The rear air chamber and the horizontal water channel jointly control the resonance period of the rear L-shaped oscillating water column device. The specific dimensions that need to be designed include: the width of the rear air chamber (the horizontal distance between the rear wall 9 of the air chamber and the rear wall 10 of the control room), the draft of the rear wall 10 of the control room (the longitudinal distance from the bottom of the rear wall of the control room to the still water surface), the height of the horizontal water channel (the longitudinal distance between the upper edge of the device bottom plate 12 and the lower edge of the control room bottom plate 11), and the width of the horizontal water channel (the horizontal dimension of the lower edge of the control room bottom plate 11).

[0041] Specifically, here is an example of the process of studying the structural dimensions of the oscillating water column conversion unit based on physical model experiments:

[0042] a. Through wave condition investigation, confirm that the annual average wave period in the target sea area is 6.0 s, the average period for a 50-year return period is 8.0 s, the design low water level is -1.5 m, and the seabed elevation is -10 m.

[0043] b. The experimental geometric scale is set at 1:25, and the time scale is 1:5. Therefore, the data within the model scale are an annual average wave period of 1.2 s, a design low water level of -0.06 m, and a seabed elevation of -0.4 m.

[0044] c. The experimental period is preliminarily determined to be 0.7 - 1.6 s, the experimental water depth is 0.4 m, and the experimental wave height is 0.04 m. In this experiment, it is planned that the draft of the front wall of the air chamber is 0.1 m, the width of the front air chamber is 0.1 m, the height of the transverse water channel is 0.1 m, and the width is 0.2 m. The resonance period is regulated by adjusting the width of the rear air chamber. For the specific cross-sectional dimensions of the experimental model, see Figure 3 , and circular orifices are opened on the top plate of the model to simulate the axial flow impulse air turbine, and the orifice ratio of each air chamber remains the same. The overall model is made of 10-mm-thick acrylic board.

[0045] d. The experiment is equipped with a 25-m-long two-dimensional wave flume, an active absorption wave maker, a wave height gauge, a pressure sensor, and a data acquisition system. The specific settings will not be elaborated here and can be referred to the relevant literature in this field (such as: Leng Jie. Experimental study on the hydrodynamic and flow field characteristics of oscillating water column breakwaters [D]. Zhejiang University, 2020. DOI: 10.27461 / d.cnki.gzjdx.2019.000147.) for the settings.

[0046] University, 2020. DOI: 10.27461 / d.cnki.gzjdx.2019.000147.) for the settings.

[0047] f. The curves of the wave-air conversion efficiency of each model varying with the wave period are as Figure 4 , and it can be found that the resonance periods of the front air chambers of Models 1 and 2 are both 0.9 s, while the resonance periods of the rear air chambers are 1.4 s and 1.6 s respectively due to the different widths of the rear air chambers. Therefore, after coupling the wave energy conversion effects of the front and rear air chambers, there are differences in the wave energy conversion performances of Models 1 and 2. The resonance period of the wave energy conversion unit corresponding to Model 1 is 1.2 s, which is more matched to the target sea conditions and can efficiently convert the wave energy of the target sea conditions. At the same time, the curve of the transmission coefficient of Model 1 varying with the wave period is shown in Figure 5 , and within the experimental wave period range, its transmittance is basically less than 0.5, meeting the wave protection requirements. Therefore, Model 1 is the preferred model.

[0048] g. Calculate the actual prototype dimensions according to the structural dimensions of Model 2 and the experimental geometric scale.

[0049] The design of thickening the bottom plate 11 of the control room and the triangular configuration of the rear wall 9 of the air chamber can enhance the resistance to the wave-induced overturning moment and ensure the reliability and stability of the device.

[0050] Round pipe orifices are reserved at the tops of the front and rear air chambers for installing air turbines.

[0051] Build a complete air turbine control system in the control room, which is built-in with the optimal rotational speed and wave parameters, specifically the corresponding relationship between wave height and wave period. It can intelligently adjust the rotational speed of the air turbine according to the incoming wave conditions to achieve efficient wave energy capture.

[0052] The wave energy conversion unit as a whole is a precast concrete component, and the construction and installation are carried out by means of overall on-site hoisting. The pile foundation uses prestressed pipe piles as the foundation piles.

[0053] The pile cap 16 is a cast-in-place concrete structure, which can be used to compensate for the deviation of the foundation pile during installation and is firmly connected to the top panel 13.

[0054] The broadband energy-capturing and wave-dissipating wave energy utilization type open breakwater disclosed by the present invention can accurately, broadband and efficiently capture energy and dissipate waves for the waves in the target sea area after being designed according to the wave climate and tide level conditions of the actual layout sea area, effectively ensuring the stable operation conditions of the water area behind the breakwater, and providing power supply for the working area and its surroundings.

[0055] The above embodiments only represent several implementation manners of the present invention, and the description thereof is relatively specific and detailed, but it should not be construed as a limitation to the scope of the patent of the present invention. For those of ordinary skill in the art, without departing from the concept of the present invention, several deformations and improvements can still be made, and these all belong to the protection scope of the present invention.

Claims

1. A wave energy utilization type permeable breakwater with wide - band energy capture and wave dissipation, characterized in that, It includes a wave energy conversion system and a bottom pile foundation support structure; the wave energy conversion system is composed of an oscillating water column wave energy conversion unit, and the oscillating water column wave energy conversion unit includes a front air chamber, a rear air chamber, a transverse water channel, an air turbine and a control room; The front air chamber is enclosed by a front wall of the air chamber, a front wall of the control room and a top plate of the device, and is located on the wave-facing side inside the wave energy conversion system; the rear air chamber is enclosed by a rear wall of the air chamber, a rear wall of the control room and a top plate of the device, and is located on the wave-back side inside the wave energy conversion system; the transverse water channel is enclosed by a bottom plate of the control room and a bottom plate of the device; the transverse water channel is respectively communicated with the front air chamber and the rear air chamber, and a spacing is provided between the bottom of the front wall of the air chamber and the bottom plate of the device as a communication opening between the transverse water channel and the external environment; air turbines are arranged at the tops of the front air chamber and the rear air chamber, and the front air chamber and the rear air chamber are communicated with the external air through the air turbines, and the control room is composed of a front wall of the control room, a rear wall of the control room, a bottom plate of the control room and a top plate of the device; Both the front air chamber and the rear air chamber are vertically arranged square air chambers. The size of the front air chamber is designed so that the resonance period of the formed front oscillating water column device corresponds to the high-frequency waves in the sea area, and the sizes of the transverse water channel and the rear air chamber are designed so that the resonance period of the L-shaped oscillating water column device corresponds to the low-frequency waves in the sea area. After the wave energy conversion performances of the front and rear oscillating water column devices are superimposed, the resonance period of the oscillating water column wave energy conversion unit is equal to the annual average wave period of the target sea area, realizing wide-band and efficient capture of wave energy, and further reducing wave energy; An air turbine control system is equipped in the control room; the air turbine control system has a built-in corresponding relationship between the optimal speed and wave parameters, and the wave parameters are wave height and wave period. The air turbine control system adjusts the speeds of the air turbines in the front air chamber and the rear air chamber according to the incident wave parameters to achieve efficient capture of wave energy; The bottom pile foundation support structure includes a pile foundation and a top panel. Among them, the pile foundation on the wave-facing side adopts a combination of vertical piles and single inclined piles, and the pile foundation on the wave-back side adopts a combination of double inclined piles. The pile foundation is connected to the top panel through a pile cap; the bottom plate of the device is installed on the top panel; The design method of the open-type breakwater includes the following steps: S1. Collect the wave conditions and tide levels in the actual layout sea area, and analyze to obtain the annual average wave period T and the designed low water level in the sea area; S2. Set the bottom elevation of the front wall of the air chamber to be 1.0 m lower than the designed low water level, and at the same time, the bottom elevation of the bottom plate of the control room is not higher than the bottom elevation of the front wall of the air chamber to facilitate the capture of wave energy by the front air chamber; S3. Determine the size of the oscillating water column wave energy conversion unit through physical model experiments or numerical simulation calculations. Among them, the size design needs to make the resonance period of the front oscillating water column device smaller than T to convert the energy of shorter periods; the resonance period of the rear oscillating water column device is larger than T to convert the energy of longer periods; and after the conversion performances of the front and rear oscillating water column devices are superimposed, the resonance period of the oscillating water column wave energy conversion unit is equal to T to achieve wide-band and efficient capture of the wave energy of the target sea area, and further achieve wave energy reduction; S4. When the sizes of the oscillating water column wave energy conversion units are determined, the optimal rotational speeds of the air turbines in the front and rear air chambers under different wave parameters are obtained through tests and stored in the air turbine control system.

2. The wave energy utilization type open breakwater with broadband energy capture and wave dissipation according to claim 1, characterized in that, Circular nozzles are provided in the device top plate areas at the tops of the front air chamber and the rear air chamber. The air turbines are installed in the circular nozzles and are used to convert the air kinetic energy into mechanical energy of their own rotation under the drive of the reciprocating air flow excited by the oscillating water column, and then drive the generator to generate electricity.

3. A wave energy utilization type open - type breakwater with broadband energy capture and wave dissipation according to claim 1, characterized in that, The bottom plate of the control room is thickened in design, which can protect the control room and increase the self-weight of the upper structure of the breakwater at the same time, enhancing the stability; the rear wall of the air chamber is in a triangular configuration, narrower at the top and wider at the bottom, and the triangular configuration can effectively resist the overturning moment brought by the wave load and enhance the structural stability.

4. A perforated breakwater of wave energy utilization type for wide-band energy capture and wave dissipation according to claim 1, characterized in that: In S3, the sizes of the oscillating water column wave energy conversion units include the sizes of the front oscillating water column device and the rear oscillating water column device. Among them, the size of the front oscillating water column device includes: the width of the front air chamber, the draft depth of the front wall of the air chamber, and the draft depth of the front wall of the control room. The size of the rear oscillating water column device includes: the width of the rear air chamber, the draft depth of the rear wall of the control room, the height of the transverse water channel, and the width of the transverse water channel.

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