JPS605790B2 - Wave energy conversion device using liquid turbine - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a device that converts wave energy using a liquid turbine, which efficiently extracts energy from waves that always exist on the surface of water such as oceans and lakes, and uses this energy for other useful purposes. The purpose is to convert it into energy.

Numerous proposals have been made to focus on wave movements on the surface of oceans and lakes, and to extract and utilize the energy they contain.

Among these methods, the methods that are currently considered to be promising for industrial use include a method in which wave energy is extracted by vertically vibrating a wave buoy according to the vertical movement of the wave, and a method in which the wave energy is extracted by vertically vibrating the wave buoy in response to the vertical movement of the wave. There is an air turbine method in which the air is compressed into an air flow that drives a turbine, and both methods are being tested for practical use. However, with the method of utilizing the vertical vibration of a floating buoy, there is a limit to the amount of energy conversion that can be extracted per device, and it is difficult to increase this amount.Furthermore, it is difficult to fix it at a fixed point, so it may drift due to the current. It has the disadvantage of being stored away. On the other hand,
In the air turbine method, the equipment is moored, so it does not drift, and if the equipment is made larger, the amount of energy that can be extracted can theoretically be increased accordingly.
Since air, which has a high compressibility and low density, is used as the energy carrier medium to drive the turbine, the overall energy conversion efficiency is poor, and as a result, only a small portion of the total energy contained in the waves is extracted. The major drawback is that it cannot be used. In addition, as a means of converting wave energy, for example, converting the vertical movement of a float into rotational movement via a mechanical intermediate mechanism, etc.
Many proposals have been made that use mechanical devices, but since the operation of the mechanical devices itself consumes a considerable amount of energy, the overall energy conversion efficiency is low, and on top of that, the Iso loom has recently broken down. It has drawbacks such as requiring a lot of effort for maintenance. In view of the above points, the present invention was developed as a result of research, and without intervening a mechanical intermediate mechanism as conventionally proposed, the present invention uses a liquid, which has a much higher density than air, as an energy transport medium to transfer the momentum of waves. By using this method to drive a liquid turbine, we have invented a wave energy conversion device that does not have the drawbacks of the above-mentioned systems. The first object of the present invention is to provide a device that efficiently extracts energy from waves on the surface of water such as the ocean, lakes, and marshes, and converts it into other useful energy.

A second object of the present invention is to provide an apparatus capable of efficiently extracting energy by converting the momentum of waves into a dense liquid flow and thereby driving a liquid turbine. .

A third object of the present invention is to provide a device that can efficiently extract a large amount of energy using a device that is easy to maintain and operate, requires no effort, and can be easily enlarged. A fourth object of the present invention is to convert the energy of waves into other useful energy, and at the same time, as a side effect, to attenuate the waves and obtain a still water surface that can be used for other useful purposes. The purpose is to provide a covering layer.

DESCRIPTION OF THE PREFERRED EMBODIMENTS The apparatus according to the present invention will be explained in detail below based on the drawings showing some embodiments thereof.

FIG. 1 is a sectional view including a liquid turbine portion of an embodiment of a device having a plurality of airtight pressurized chambers used in the device of the present invention, and the figure shows an example in which two airtight pressurized chambers are arranged side by side. There is a type in which the liquid storage tank is not fixed and the liquid storage tank floats.

In the figure, 1 is a box made of steel plate etc. whose bottom is open underwater, and has an appropriate length in the direction perpendicular to the plane of the paper.
The inside in the horizontal direction of the drawing is approximately the same as the average wavelength of the waves, and the inside thereof is separated by a partition plate 2 into two airtight pressurized chambers 3 and 4. 6 and 6 are liquid storage tanks for storing liquid whose upper parts are closed in airtight pressurized chambers, which are made shorter than the box body 1 in the direction perpendicular to the paper, and both liquid storage tanks have buoyancy imparting bodies 7 at their bottoms. The tank shall have enough buoyancy to prevent the tank from sinking even when the tank is filled with liquid, and an appropriate number of pulleys 8 will be attached to the side of the tank to ensure smooth vertical floating. ing.

9, IQ, 11 and 12 are conduits, each having a valve mechanism 13, 14, 15, 16 at one end and connected to a liquid turbine 17 at the other end.

The liquid turbine 17 and the way in which the liquid turbine is connected to each conduit are shown schematically in the figures for ease of understanding, but may be modified according to known engineering methods in practice. For example, in the figure, each conduit is connected to the liquid turbine separately, but as shown in FIG. However, the conduits 15 and 16 may be integrally connected to the discharge port side of the liquid turbine. Although the rotating shaft of the liquid turbine is installed in the direction perpendicular to the plane of the paper in the figure, this is not limited to this direction.Furthermore, if the liquid turbine is installed at the top of the box 1, it will be easy to use when repairs are required. convenient. The device used in the present invention constructed and manufactured as described above has an appropriate amount of liquid in the liquid storage tank, the upper half of the box protrudes above the waving water surface, and the horizontal direction of the drawing matches the traveling direction of the waves. A steel element or chain 18 having the required length and strength and floating in a direction such that
It grows and floats on the bottom 19 of the water. Next, the operation of the apparatus used in the present invention, manufactured as described above and floated on a waving water surface, will be explained.

It is assumed that there is a wave shown by a virtual line W on the outside of the device, and it travels in the direction of the arrow. As mentioned above, the inside of the machine in the diagram of the device is designed and manufactured so that it is almost equal to the wavelength of the wave, so if you look at one airtight pressurized chamber, it corresponds to 1/2 the skin length, and therefore the progress of the wave When the wave water surface outside the device rises and falls as a result, the water in both airtight pressurized chambers is subjected to forces in opposite directions, respectively. Now, if a part of an airtight pressurized room has a hole that communicates with the outside air, the water level inside the room would rise and fall freely according to the rise and fall of the undulating water surface on the outside, but in the case of the device of the present invention, it can be made airtight. As a result, the air inside the airtight pressurized chamber is compressed or depressurized at the same time as the liquid storage tank stored inside rises and falls, depending on the rise and fall of the undulating water surface outside. . In the case of the embodiment shown in Fig. 1, since the two airtight pressurized chambers are provided adjacent to each other, the liquid storage tank in one of the airtight pressurized chambers rises, and the air in the chamber receives a force in the compression direction. When receiving liquid, the liquid storage tank in the other airtight pressurized chamber lowers,
Moreover, the air in the room is subjected to a force in the direction of pressure reduction, and the resulting force due to fluctuations in the liquid level and air pressure acts on the liquid level stored in the liquid storage tank.

Therefore, in the illustrated state, the air in the airtight pressurized chamber 3 is compressed and the air in the airtight pressurized chamber 4 is depressurized, and these forces act on the liquid surface in the liquid storage tank. Due to the liquid level difference between the liquid tanks as well as the pressure difference between the two gas-tight pressurized chambers, the liquid in the liquid storage tank 5 creates a liquid flow in the conduit 9 through the valve mechanism 13.
After driving the liquid turbine 17, the conduit 12 and the valve mechanism 16
It then moves into the liquid tank 6. Next, the wave motion on the outside of the device advances in the direction of the arrow, and the liquid storage tank in the airtight pressurized chamber 3 descends, and the air in the chamber 3 moves in the decompression direction, causing the liquid storage tank in the airtight pressurization chamber 4 to fall. When the tank rises and the air in the chamber 4 changes in the pressurizing direction, the liquid level difference and the pressure difference between the two chambers are reversed, so the liquid in the liquid storage tank 6 is moved by the valve mechanism in the opposite way to the above. A liquid flow is created in the conduit 10 through the conduit 14, which drives the liquid turbine, and then returns to the liquid storage tank 3 via the conduit 11 and the valve mechanism 15. In addition, in the embodiment shown in FIG. 1, due to the liquid level difference between the two liquid storage tanks and the pressure difference between the two airtight pressurized chambers, the liquid level between the two liquid storage tanks is eventually This produces a liquid level difference in height that is balanced by the liquid level and pressure difference.

When the waves outside the device move and the rise and fall of the liquid storage tank between the two airtight pressurized chambers and the pressure difference between the two airtight pressurized chambers begin to reverse, this liquid level between the two storage tanks begins to rise. Due to the difference, a liquid flow occurs, and even if the lifting and lowering of the liquid storage tank and the pressure difference between the two airtight pressurized chambers have not yet completely reversed and caused a pneumatic force to act in the opposite direction, this will cause the liquid to flow according to the drawing. For example, a liquid flow is created in the conduit 10 from the liquid storage tank 6 through the valve mechanism 14, and after driving a liquid turbine, the liquid is returned to the liquid storage tank 5 through the conduit 11 and the valve mechanism 15. When the liquid storage tank goes up and down and the air pressure in both airtight pressurized chambers is completely reversed, the conduit 1
During zero, the liquid flow continues, and the liquid level in the liquid storage tank 5 continues to rise, gradually becoming higher than the liquid level in the liquid storage tank 6, and finally reaches a height that is again balanced by the pressure difference between the two chambers. This creates a liquid level difference between the two liquid storage tanks. The generation of liquid flow due to this difference in liquid level occurs during the rest period when a type of vibration phenomenon such as a wave changes its direction of motion from one direction to the opposite direction, without stopping the rotation of the liquid turbine. This plays an important role in maintaining smooth rotation. especially,
In the present invention, since the liquid storage tank itself has buoyancy and floats with the rise and fall of the water surface in the airtight pressurized chamber, in addition to the movement of liquid due to the pressure difference between the two airtight pressurized chambers, The action is based on weight.

Moving away from the drawing, first of all, if the same amount of liquid is stored in both liquid storage tanks, and the liquid level in both tanks is the same when placed on a still water surface, the peak of the wave will approach the outside, When the water level in the airtight pressurized chamber 3 rises and the water level in the airtight pressurized chamber 4 begins to fall, the liquid storage tank 5 rises with the water level, and the liquid storage tank 6 descends with the water level, causing both liquid storage tanks to rise. A difference in liquid level occurs between the liquid levels stored. This liquid level difference generates a liquid flow from the liquid storage tank 5 toward the liquid storage tank 6, and the speed of the liquid flow caused by the above-mentioned pressure difference between the airtight pressurized chambers is further accelerated. Furthermore, both liquid storage tanks float in the water inside the airtight pressurized chamber, and the liquid storage tank 5 on the side from which the liquid flows out has increased buoyancy by the amount of liquid reduced, so that the water surface in the airtight pressurized chamber 3 increases. As the buoyancy of the liquid storage tank on the side into which the liquid flows decreases, it sinks accordingly into the water surface in the airtight pressurized chamber 4, which prevents the continuation of the liquid flow caused by the difference in liquid level and the By contributing to an increase in the pressure difference between airtight pressurized chambers. When the wave motion reaches its maximum on the airtight pressurized chamber 3 side, the position is exactly as shown in Fig. 1, and after that, the liquid storage tank on the airtight pressurized chamber 3 side begins to fall together with the water level in the room, and on the other hand, the airtight pressurized The liquid storage tank on the chamber 4 side begins to rise along with the water level in the room, but even at the moment when this direction is reversed, the liquid flow from the liquid storage tank 5 to the liquid storage tank 6 does not stop, and the liquid turbine continues to flow. The drive never stops. Then, from the point where the liquid level difference between the two storage tanks disappears again, and the air pressure force due to the pressure difference between the two airtight pressurized chambers acts in reverse, as explained earlier, the air pressure force due to the pressure difference acts. Together with the liquid level difference, a liquid flow flows through the conduit from the liquid storage tank 6 side to the liquid storage tank 5 side, driving the liquid turbine. In this way, the present embodiment drives the liquid turbine very effectively, as a liquid flow is always created in either direction in the conduit, regardless of the phase of the wave cycle. In the embodiment shown in FIG. 1, in addition to the liquid flow due to the pressure difference, the effect of the liquid level difference makes a large contribution, so the discharge side conduits 11 and 12, which are closer to the valve mechanism, are connected as shown in the figure. The relative thickness is effective in accelerating the liquid flow in conduits 9 and 10. The above explanation was given for two airtight pressurized chambers placed side by side, but by installing a large number of airtight pressurized chambers each having a liquid storage tank, the liquid level difference and pressure fluctuation caused from above and below the wave surface can be corrected. A liquid flow is created in a conduit with a valve mechanism from the liquid storage tank in the airtight pressurized chamber in the direction toward the liquid storage tank in the airtight pressurized chamber where the liquid level difference and pressure fluctuation are in the negative direction. If this liquid flow drives a liquid turbine, even greater amounts of energy can be extracted.

In addition, the inside of the airtight pressurized chamber with the liquid storage tank is made into a 1' gold skin length of the wave, and a plurality of such airtight pressurized chambers are floated at intervals of 1'2 skin length of the wave. Good results can also be obtained for the same aircraft by connecting a conduit from a liquid storage tank in an airtight pressurized chamber to a liquid turbine. Next, the embodiment shown in FIG. 2 has a single airtight pressurized chamber and is inferior in efficiency compared to the above embodiment), but has a simple configuration and is included within the scope of the device of the present invention. It is something.

In FIG. 2, parts having the same functions as those in FIG. 1 are denoted by the same reference numerals, and in FIG. 2, two springs 21 are elastic bodies. If the example shown in the turtle diagram above is called a closed type liquid system, this example can also be called an open type liquid system, and the change in pressure between the atmospheric pressure and the pressure change in the airtight pressurized chamber is important. Both the pressure difference and the liquid level difference between the liquid level in the reservoir in the airtight pressurized chamber and the external wave surface produce the same effect as described with respect to Figure 1. It is used to create a liquid turbine and drive a liquid turbine.
If the embodiment shown in the official drawing is a Bush-Bull type, the second
The one shown in the figure is a single type, so the bush
Although it cannot extract as much energy as the bull type, it has the advantage of being simple in construction. The difference between the two is that during stormy weather such as a typhoon, the air in the airtight pressurized chamber is removed, the entire device is sunk to the bottom of the water, and once the typhoon has passed, air can be injected to bring it to the surface and resume operation. There isn't. The buffer spring 20 and the elastic body 21 are provided to prevent the liquid storage tank from hitting the ceiling of the box body and causing a malfunction of the device in the event of unexpected stormy weather. As detailed above,
In the device of the present invention, a high-speed flow of liquid is created in the conduit by using the pressure change in the airtight pressurized chamber caused by the vertical movement of the wave water surface and the difference in the liquid level in the liquid storage tank, and this creates a liquid turbine. Since it is driven to extract energy in waves, excellent effects as described below can be obtained.

First of all, in the device of the present invention, the energy transfer medium used to drive the turbine is a liquid that has a much higher density than air, so if the same amount of energy is transferred at a dynamic speed through the conduit, Assuming that the medium flows, the device of the present invention can transport a much larger amount of energy and drive the turbine more efficiently than the known air turbine system. This means that the momentum of a moving body (
Considering that the energy) is expressed by the formula V2 (m is mass, V is velocity) of 1'2 (the mass per unit volume of seawater is about 80" moss or more compared to air), It will be clear that the device according to the invention, which uses a liquid as the energy-carrying medium, can efficiently transport energy to drive a turbine and extract energy in wave motions. It simply utilizes the pressure difference between the air compressed in the pressure chamber and the atmospheric pressure.In that sense, in accordance with the embodiment of the device of the present invention described above, it is a second method that is less efficient. Although it is a single type device similar to the example shown in the figure, in the device of the present invention, even though it is the embodiment shown in FIG. It operates much more efficiently.

Next, in the device of the present invention, the liquid level difference between the liquid storage tanks,
However, the liquid flow in the conduit caused by the difference in liquid level between the liquid level in the liquid storage tank and the external wave surface has a great effect.

This liquid flow due to the liquid level difference cannot be expected in an air turbine system, and is unique to the apparatus of the present invention. The liquid flow due to this liquid level difference not only has the effect of accelerating the speed of the liquid flow flowing in the conduit due to the pressure difference caused by the airtight pressurized chamber, but also has an even heavier effect, like a wave motion. A type of oscillatory phenomenon is that the liquid turbine does not stop rotating, even for a short period of rest when changing its motion from one direction to the other. Therefore, the flywheel attached to the liquid turbine can be small, so the inertia at the start of operation is small, and not only can constant speed rotation be quickly started, but also smooth turbine rotation can be obtained. can. Furthermore, when implementing the apparatus of the present invention in an embodiment having a plurality of pressurized airtight chambers as shown in FIG.
Because the pressure differences between the pressurization and depressurization of the air in multiple airtight pressurized chambers act synergistically, the speed of the liquid flow flowing through the conduit is further accelerated, and the kinetic energy is proportional to the square of the speed, so the liquid turbine is activated. The driving force increases accordingly.

Furthermore, since this embodiment is a closed liquid system, if a liquid with low corrosivity and high specific gravity is stored in the liquid storage tank, the speed of the liquid flow due to the difference in liquid level can be accelerated by that amount. Since the device used in the present invention has no mechanical parts other than the liquid turbine, there is almost no energy loss due to mechanical mechanisms, and once it is installed, it can be operated without any special maintenance. is also easy.

Furthermore, if seawater is used as the liquid in the storage tank, ``In the event of an emergency such as a typhoon, the air in the airtight pressurized chamber is removed, the entire device is submerged underwater, and when the weather improves, air is injected and the system is resurfaced.
This has the effect of allowing you to easily resume normal operation. Furthermore, when the device used in the present invention is installed in a suitable location offshore and the device of the present invention is implemented, the energy contained in the wave motion and causing the wave motion is efficiently absorbed and extracted by the device and the turbine It turns into rotational energy,
Furthermore, as a result of being converted into other useful energy such as electric power, a side effect of implementing the present invention is that the waves that pass through the location where the device is installed lose most of their energy and become attenuated. It is. Therefore, the suction surface from the place where the device used in the present invention is installed to the beach becomes a static suction surface with extremely calm waves, which can be used for installation of structures such as offshore plants, etc.
It can be used for aquaculture operations, yacht harbors, and other uses. Of course, the waves do not completely disappear from the water surface; some waves still remain due to the circular motion of the water particles that are the source of the wave motion that has passed under the device. In order to further prevent this, as seen in the figures of each embodiment, a wire mesh 22 having an appropriate length is attached to the rear lower end of the device along the longitudinal direction of the box 1, and a wheel awl 23 is attached to the lower end of the wire mesh 22. If the device is suspended, the circular motion of water particles passing through the bottom of the device will be interrupted or disturbed.
As a result, the waves remaining on the water surface behind the device become even smaller. This wire mesh 22 is not only useful for wave dissipation, but also
It can also be effectively used as a culture medium for shellfish such as oysters and seaweed. As mentioned above, several embodiments of the present invention have been given and the functions and effects thereof have been described in detail, but the embodiments of the present invention are not limited to the above embodiments, and it goes without saying that various embodiments within the scope of the claims may be implemented. Of course, it can be implemented in the following manner.

[Brief explanation of drawings]

FIG. 1 is an explanatory cross-sectional view showing one embodiment of a wave energy conversion device according to the present invention, and FIG. 2 is an explanatory cross-sectional view showing another embodiment. 1 is a box body, 2 is a partition plate, 3 and 4 are airtight pressurized chambers, 5 and 6
1 is a liquid storage tank, 7 is a buoyancy imparting body, 8 is a pulley, 9 to 12 are conduits, 13 to 16 are valve mechanisms, 17 is a liquid turbine, 18 is steel, 19 is a water bottom, 20 is a buffer spring, 21 is a Elastic body, 2
2 is a wire mesh, and 23 is a vertical cone. Figure 1 Figure 2

Claims (1)

[Claims] 1. A liquid storage tank for storing liquid is vertically movable floating in an airtight pressurized chamber whose bottom part is open in the water and floats on the waving water surface, and the liquid storage tank in the airtight pressurized chamber and this A liquid flow is generated in a conduit communicating with a liquid existing outside the airtight pressurized chamber or a liquid in a liquid storage tank provided in another airtight pressurized chamber, and the liquid turbine is driven by the liquid flow. A wave energy conversion device using a liquid turbine, characterized in that: