JPH0554528B2 - - Google Patents

Description

[Detailed description of the invention] [Industrial application field] The present invention can be installed in deep sea and shallow sea,
The present invention relates to a wave energy absorption system that can effectively absorb irregular wave energy and easily create calm sea areas and reduce wave force acting on ships and marine structures.

[Conventional technology]

Generally, devices for absorbing wave energy having various configurations have been proposed as wave power generating devices or wave dissipating devices, and some of them have been put into practical use. However, most of these wave energy absorption devices, whether floating or fixed, match the wave period with the natural period of the vibration of the floating body or water column, bring them into resonance, and apply an appropriate load to them. It is based on the theory that the energy of waves is absorbed by adding
(Refer to Publication No. 26266). In addition, these devices consist of a single floating body or a water column, and in the case of a floating body, the natural period corresponds to the wave period by changing the mass or restoring force coefficient of the floating body.
Furthermore, in the case of a water column, measures have been taken to absorb wave energy without changing the natural period.

[Problem that the invention seeks to solve]

However, it is possible to realize the above theory of absorbing wave energy with a wave energy absorbing device consisting of a single floating body or a water column in an aquarium experiment that generates regular waves.
In irregular waves in actual sea areas, it is impossible to keep the mass and restoring force coefficient of a floating body or water column in an optimal state in response to changes in the wave period. In other words, in order to efficiently absorb the energy of irregular waves, the entire device or a part of it must resonate with the periods of all the waves that make up the irregular waves, but conventional wave energy absorption Since the device attempts to match the natural period to the average period of irregular waves by the volume of the floating body or water column, it is conversely limited by the volume and cannot combine multiple waves with different natural periods. . Therefore, it must be said that it is impossible to completely absorb the energy of irregular waves by mechanical control as in the past. In addition, devices based mainly on fixed structures have the disadvantage that the wave-dissipating effect varies significantly depending on changes in the water level, resulting in poor reliability and convenience.

SUMMARY OF THE INVENTION Therefore, an object of the present invention is to provide a wave energy absorption system that can efficiently absorb the energy of irregular waves without using complicated mechanical devices.

[Means for solving problems]

The wave energy absorption system according to the present invention is provided with a partition chamber that is bent or curved with respect to the water surface to form a water column that is affected by gravity, and absorbs when the water column vibrates under the force of waves. The present invention is characterized in that a pressure control chamber communicating with the partition chamber is provided for controlling the pressure.

In the wave energy absorption system, one or both ends of the partition are located underwater, and the water column formed within the partition is directly subjected to the forcing force of waves and is also affected by gravity, so that each has its own vibration period. Configure.

In this case, the pressure control chamber is configured to close the other end of each partition to form an air chamber, and the air chambers are configured to communicate with each other and with the atmosphere through a required orifice, or The air chamber may be formed as an independent air chamber, and the air chamber and each partition chamber may be communicated with each other through a pipe, and an orifice may be provided in the air chamber to communicate with the atmosphere.

Further, it is preferable to provide a weir to control the movement of the water column approximately in the middle of the partition chamber.

[Effect]

According to the wave energy absorption system according to the present invention, each of the plurality of water columns formed in the partition has a natural period, and these natural periods are independent of the cross-sectional shape and cross-sectional area of the water column, and are independent of the length of the water column. Even if one or both ends of each water column are submerged in the water column, the action of gravity acts on each water column, so regardless of the shape of the water column, the water column in the partition room Similarly, since it has a natural period, it can effectively absorb the energy of irregular waves.

As described above, according to the present invention, by allowing a large number of water columns each having a different natural period to collectively exist in the same ocean area, the water column formed in each partition chamber can be effectively controlled against fluctuations of irregular waves. It becomes resonant with either of the waves, and as a result, the energy of the irregular waves can be efficiently absorbed.

〔Example〕

Next, embodiments of the wave energy absorption system according to the present invention will be described in detail below with reference to the accompanying drawings.

FIG. 1 shows a typical embodiment of the wave energy absorption system of the present invention. That is,
This embodiment shows a case where the system of the present invention is installed on the sea surface in a deep sea area. Reference numeral 10 indicates legs fixed to the seabed, and a plurality of partitions 12 are arranged at predetermined intervals on the upper part of these legs 10 so as to be located below the water surface, and both ends are closed to form a multi-stage passage-like partition. A chamber 14 is configured. These partitions 14 have an upwardly inclined part 14a, a horizontal part 14b, and a vertical part 1.
4c, one end of the upwardly inclined part 14a opens into the water, and the other end of the vertical part 14c extends above the water surface and is sealed, forming an air chamber 18 inside. The air chambers 18 formed in each partition 14 communicate with each other by providing an orifice 20 in a part of the partition plate 12, respectively. Further, an orifice 20a is provided in a part of the air chamber 18 that is in contact with the atmosphere side, so that the air chamber 18 is opened to the atmosphere side. The partition room 14 configured in multiple stages in this way
is set so that water enters the interior and forms water columns, and these water columns are influenced by gravity due to the bending of each part of the partition chamber 14 described above. Also,
The lengths of these partitions 14 are set so that the natural period of vibration of each water column corresponds to the period included in the irregular wave (in the range of about 3 seconds to 20 seconds). Furthermore, a weir 1 is installed approximately in the middle of the partition chamber 14 to disturb the water column and suppress its movement.
6 will be provided. Therefore, this weir 16 can be set so as to work together with the air chamber 18 described above to halve the movement of the water column that fluctuates under the force of waves. In this case, the orifice 20 provided in each air chamber 18 has an opening ratio of 1/50 to 1/15.
It is preferable to set it to 0. Further, in this embodiment, a case is shown in which the air chamber 18 is provided corresponding to each partition chamber 14, but it is also possible to provide a single air chamber and make each partition chamber communicate with this air chamber.

By arranging a large number of block bodies in this embodiment configured in this manner in a predetermined deep sea area, when the energy of irregular waves is transmitted to the water column formed in each partition chamber 14, The water column having this natural period and the period of the irregular wave enter into a resonant state, and the energy can be efficiently absorbed.

FIG. 2 shows another embodiment of the wave energy absorption system of the present invention. That is, this embodiment shows a case where the system of the present invention is installed in a shallow sea area. In this embodiment, a plurality of partition plates 12 are placed on a mound 22 built in advance on the seabed, separated by a predetermined interval so as to be located below the water surface, and both ends are closed to form a multi-stage passage-like partition chamber 14. do. In this case, the partition 14 has a vertical section 14
x, a horizontal portion 14y, and a vertical portion 14z, and the vertical portions 14x and 14z at both ends are symmetrical and each open into the water. However, in this embodiment, a single air chamber 18 is provided at the top of the partition chamber 14 so as to be in contact with the atmosphere side, and this air chamber 18 and each partition chamber 14 are connected through pipes 24, respectively. . In addition, in this embodiment as well, as in the above-mentioned embodiment, water enters the interior of each partition chamber 14 to form a water column, and these water columns form a water column in the partition chamber 1.
4 is set to be affected by gravity by bending each part. Furthermore, the lengths of these partitions 14 are set so that the natural period of vibration of the water column corresponds to the period included in irregular waves (in the range of approximately 3 seconds to 20 seconds). Furthermore, a weir 16 is provided approximately in the middle of the partition chamber 14 to disturb the water column and suppress its movement. Further, the air chamber 18 is provided with an orifice 20a that communicates with the atmosphere side and has an aperture ratio of 1/50 to 1/150.

By arranging a large number of blocks in this embodiment configured in this manner in a predetermined shallow sea area, it is possible to absorb the energy of irregular waves in the same way as in the previous embodiment. However, in the case of this embodiment, since both ends of each partition chamber 14 are opened into the water, the wave energy absorption efficiency is lower than that of the above embodiment, but it does not solve the problem of conventional breakwaters, etc. One of the drawbacks of no seawater exchange can be solved, and thereby not only can environmental deterioration of inland seawater be prevented, but also a sufficient wave-dissipating effect can be obtained. Therefore, according to the system configuration according to this implementation, the above-mentioned functions and effects can be fully expected regardless of whether the block body is fixed to the seabed or moored in the sea or on the sea surface. It is also effective when using a tension leg mooring method in which the cable is constantly kept under tension.

〔Effect of the invention〕

As is clear from the above-mentioned embodiments, according to the present invention, by providing a partition that forms a large number of water columns with different natural periods, each water column can disperse and absorb the energy of irregular waves. Therefore, there is no need for complex control of mass, spring coefficient, etc., as is done with conventional energy absorption devices, and the system is in a state where maximum energy absorption can be achieved when each water column always vibrates at its natural period. can be set, so high energy absorption can be efficiently achieved with a simple configuration.

In addition, the system of the present invention can be appropriately installed in deep sea areas or shallow sea areas, and can also be configured so as not to impede seawater exchange, so it plays an important role in preserving the marine environment as well as having a wave-dissipating effect. be able to. The system of the present invention can also be installed as ancillary equipment integrated with any type of floating or fixed marine structure, and in this case, it can easily and effectively utilize the wave force acting on the marine structure. It can be reduced.

Furthermore, in the system of the present invention, the pressure change in the air chamber is controlled by an orifice, and by attaching an energy conversion device such as a turbine in relation to this orifice, the required energy can be obtained and used for the purpose. It can be used for.

Although the preferred embodiments of the present invention have been described above, the present invention is not limited to the above-described embodiments. The present invention can be easily and economically applied as various wave energy absorption devices, and it goes without saying that various other design changes can be made without departing from the spirit of the present invention.

[Brief explanation of the drawing]

FIG. 1 is a cross-sectional perspective view of a main part of a block installed in a deep sea area showing one embodiment of the wave energy absorption system according to the present invention, and FIG. 2 shows another embodiment of the wave energy absorption system according to the present invention. FIG. 2 is a sectional view of the main parts of a block installed in shallow water. 10... leg body, 12... partition plate, 14... partition room, 16... weir, 18... air chamber, 20... orifice, 22... mound, 24... pipe.

Claims (1)

[Claims] 1. A partition chamber is provided that is bent or curved with respect to the water surface to form a water column that is affected by gravity,
A wave energy absorption system comprising: a pressure control chamber communicating with the partition chamber for absorbing vibrations when the water column vibrates due to forced force by waves. 2. In the wave energy absorption system according to claim 1, one or both ends of the partition are located underwater, and the water column formed within the partition is directly subjected to the force of waves and is also affected by gravity. A wave energy absorption system configured so that each wave has a unique vibration period. 3. In the wave energy absorption system according to claim 1, the pressure control chamber closes the other end of each partition to form an air chamber, and the air chambers are communicated with each other via a required orifice. A wave energy absorption system configured to communicate with the atmosphere at the same time. 4. In the wave energy absorption system according to claim 1, the pressure control chamber is composed of an independent air chamber, and the air chamber and each partition chamber are communicated with each other by a pipe, and an orifice is provided in the air chamber. A wave energy absorption system configured to communicate with the atmosphere. 5. The wave energy absorption system according to claim 1, which comprises a weir for controlling the movement of the water column located approximately in the middle of the partition. 6. A wave energy absorption system for reducing wave force on a ship or marine structure, which comprises partitions arranged around the ship or marine structure in a wave energy absorption system according to claim 1.