JPH0525754B2 - - Google Patents

Description

[Detailed Description of the Invention] [Industrial Application Field] This invention relates to a mooring device for an underwater water tank, and in particular, it stores water on land such as a river in the sea and converts this stored water into seawater as needed. The present invention relates to a mooring device for mooring an underwater water storage tank that uses the difference in specific gravity of fresh water to be supplied to the ground so that it is not washed away by tidal currents.

[Prior Art] Our country is an island nation extending from southwest to northeast, with mountains running through the center like a spine. For this reason, rainwater flows through mountainous areas, collects in rivers, and flows into the sea through short stretches of flatland. Therefore, in our country, the period during which rainwater remains on the ground is extremely short. In other words, most of the supplied water resources are discarded into the ocean without being used. This creates a serious problem of water scarcity, especially in areas with low rainfall or where much of the rainfall is concentrated at one time of the year. Furthermore, in other regions, similar problems of water shortages will occur if rainfall ceases for a long period due to climatic changes. For this reason, water storage dams, reservoirs, etc. have been established in various places, and the problem of water shortage has been solved, although not completely. The reality is that even in our country, which is generally said to have a relatively good water situation, such artificial means are necessary for water storage, and in countries with worse water conditions than ours, even more powerful methods are needed. It is obvious that measures to utilize water resources are required.

Water storage dams and reservoirs temporarily store part of the water resources provided by rainfall above ground for later needs. Large areas of land are required to store significant amounts of water above ground. Therefore, when newly installing such water storage means,
This inevitably accompanies the difficulty of securing land. Furthermore,
Difficult issues may arise, such as compensation for environmental destruction and relocation of people's homes. Also, storing a significant amount of water above ground requires a sturdy structure.
Constructing such a robust structure requires enormous effort and expense. The stored water comes into contact with the atmosphere through a large surface. Therefore, in a dry and hot climate, the amount of water wasted through evaporation cannot be ignored.

Therefore, by changing the concept of conventional water storage means of securing water resources on the ground, the applicant proposed a new form that could solve the various problems mentioned above. He first proposed a means of storing water (see Japanese Patent Application Laid-open No. 146566/1983).
To briefly explain the water storage means proposed by the applicant of the present application, a water storage tank for storing water on land such as a river is provided under the sea. This water storage tank includes a water storage portion including a first portion below the sea surface and a second portion above the sea surface, and a water supply pipe and a drain pipe connected to the water storage portion. The first part forms a water storage chamber isolated from the sea, and the second part communicates with the first part and the atmosphere, and the water level varies depending on the water depth of the first part due to the difference in specific gravity between seawater and fresh water. keep. According to this new form of water storage means, seawater storage tanks, the water resources provided by rainfall are stored in seawater for later use. Because water is stored in the ocean, there are no problems associated with dams or reservoirs, such as the difficulty of securing land or compensation for environmental destruction or relocation of human residences. Water storage tanks receive water pressure from inside and outside, so their structure does not need to be as strong as a dam. Therefore, it is relatively easy to construct and has excellent economic efficiency. Further, according to this underwater water tank, the contact area between the stored water and the atmosphere can be easily and reduced, and the stored water resources are not wasted due to evaporation.

[Problems to be Solved by the Invention] As described above, the seawater storage tank proposed by the applicant has various excellent effects. However, when a large-scale seawater reservoir is installed under the sea, there is a risk that the reservoir will be washed away by the large force exerted by the tidal currents. There is also a possibility that the water tank may be deformed by the tidal currents, causing the water level in the second portion to fluctuate. Furthermore, it could change the direction of tidal currents within the bay, causing environmental changes. As described above, while the seawater storage tank proposed by the present applicant has various excellent effects, there are also problems that need to be solved.

This invention was made in order to solve such problems, and it is possible to prevent underwater water storage tanks from being washed away by tidal currents and to prevent the underwater water storage tanks from causing changes to the environment. The purpose is to provide a mooring device for a water tank.

[Means for Solving the Problems] A mooring device for underwater water storage according to the present invention includes rope means for mooring an underwater water tank, winding means for winding up each rope means, and a mooring device for mooring an underwater water tank, a winding means for winding up each rope means, and a mooring device for mooring an underwater water tank. and a control means for controlling the amount of hoisting of each hoisting means based on the detection result of the tidal current detecting means.

[Operation] The control means in the present invention controls the amount of hoisting of each hoisting means based on the direction and speed of the tidal current around the water tank detected by the tidal current detection means, thereby controlling the amount of hoisting of the underwater water tank. Transform to reduce fluid resistance to tidal currents.

[Example] First, an example of an underwater water tank to which the present invention is applied will be described.

FIG. 2 is an explanatory diagram showing a preferred embodiment of the underwater water tank. As shown in the figure, a river 3 flows from the inland part of the land 1 toward the sea 2. A water supply station 4 is provided at a suitable point above sea level upstream of the river 3 to take in river water. The taken water is conveyed through the water supply pipe 5.

The water supply station 4 may take any form as long as it can introduce water from the river 3 into the water supply pipe 5. For example, the river 3 may simply be branched to the inlet (water supply point) of the water supply pipe 5.
Preferably, however, means for disposing of debris in the water and for regulating the amount of water will be provided for smooth water supply.

The water supply pipe 5 consists of a pipe 6 made of metal, for example, in the land area 1, and a pipe 7 made of flexible cloth or plastic, for example, in the sea area 2. The pipe 6 may be buried underground, placed in contact with the ground, or maintained at a constant height above the ground. The tube 7 is most simply allowed to float naturally above the sea surface. Floats may be attached to tubes 7 at appropriate locations to provide buoyancy. Of course, the tube 7 can also be maintained at a constant depth under the sea or at a constant height above the sea by suitable support means. The tubes 6 and 7 may be made of any suitable material other than metal, cloth or plastic. Generally, the most appropriate factors such as the material, thickness, and installation method of the water supply pipe 5 are selected from among those currently available, taking into consideration the distance, amount, environment, etc. of water supply.

The water carried by the water supply pipe 5 is transferred to the water inlet pipe 8.
The water is supplied to the water storage tank 9 through the water tank 9. Details of the water storage tank 9 are shown in FIG. 3 and will be described later. The water stored in the water storage tank 9 is
If necessary, it is supplied to the drain pipe 11 through the water outlet pipe 10 and transported. The drain pipe 11, like the water supply pipe 5, consists of a pipe 12 in the sea 2 part and a pipe 13 in the land 1 part. Selection of factors such as material, thickness, installation method, etc. is the same as described above regarding the water supply pipe 5.

The water carried by the drain pipe 11 is transferred to the land 1
The water is drained at a drainage field 14 located at a suitable point above sea level. Means may be provided in the drainage field 14 for regulating the amount of drainage. The drained water is used as it is or after being treated depending on the desired use. For example, drainage field 14
can be used as a water source for gray or municipal water supplies. The drainage field 14 in FIG. 2 is shown as a water source for gray water, and industrial water is supplied to each factory from the drainage field 14 provided in an industrial area through branched industrial water pipes 15. The drainage field 14 can also be used as an agricultural irrigation water source. In this case, branched agricultural waterways would extend from the drainage field 14 to each farmland. Of course, the above-mentioned use is just an example, and this underwater water tank can be used for any purpose as a water source. Furthermore, it is not necessary to drain water once in the drainage field 14; for example, the drainage pipe 11
itself may branch to desired locations. FIG. 3 is a schematic perspective view showing a preferred example of the water storage tank 9. In the figure, the sea level is indicated by a dashed line. The water storage tank 9 consists of a first portion 16 below the sea surface and a second portion 17 above the sea surface. A float plate 18 is provided at the boundary between the first portion 16 and the second portion 17 to provide appropriate buoyancy to the water storage tank 9. 1st part 1
6 and the second part 17 are in communication, and the first part 1
A part of the water stored in the second part 6 is pushed up to the second part 17 due to the difference in specific gravity between seawater and fresh water.

The second portion 17 above the sea surface is constituted by a hollow cylinder 19 of an appropriate thickness, both ends of which are open. The float plate 18 has a disc shape with an appropriate thickness, and a circular opening is provided in the center of the float plate 18, into which a cylinder 19 is fitted.

As shown in the figure, the cylinder 19 must be capable of storing water 24 pushed up from the second portion below the sea level to a certain level. However, the environment in which it will be installed is at sea. Taking this into consideration, a material with excellent strength and corrosion resistance is selected as the material for forming the cylinder 19. For example, a metal tube whose surface is coated with a corrosion-resistant paint may be used.

The float plate 18 is for providing appropriate buoyancy to the water storage tank 9. Moreover, it is constantly in contact with seawater. Therefore, the material for forming the float plate 9 is selected to be excellent in corrosion resistance and sufficiently lighter than seawater. For example, plastic can be used and may be laminated with other materials to improve strength. It is also conceivable to make it hollow to increase buoyancy. float plate 1
The lower side of the bag 8 is always in contact with the water stored in the bag 20. Therefore, regardless of waves on the sea surface, the float plate 18 receives a uniform force from the water stored below, and is protected from destruction due to uneven force.

The first portion 16 consists of a flexible cylindrical bag 20 for storing water and a similarly cylindrical net 21 covering the outer periphery of the bag 20. The lower end of the bag 20 is closed, and the upper end is fixed to prevent seawater from entering near the outer periphery of the lower surface of the float plate 18. The upper end of the cylindrical net 21 surrounds the fixed portion of the bag 20 and is fixed near or on the outer circumference of the lower surface of the float plate 18. The lower end of the net 21 may be closed or open. Net21 is
Preferably, a plurality of annular weft threads 22 connected by a plurality of warp threads 23 is used. The purpose of the net 21 is to restrict the lateral expansion of the bag 20, and this purpose is achieved by the action of the annular weft thread 22. That is, the bag 20 has an annular weft thread 22
It is restricted by the diameter and cannot expand laterally beyond its diameter.

The bag 20 must be flexible so that its volume changes depending on the amount of water stored therein. Furthermore, it must be possible to isolate the stored water from seawater. However, bag 20 is
Since it is maintained in an equilibrium state by the pressure of water from the inside and the pressure of seawater from the outside, the material itself does not need to be very strong. Taking these points into consideration, a material that is flexible and has excellent water resistance is selected as the material for the bag 20. For example, waterproof cloth like tent fabric, vinyl, etc. can be used. The net 21 only needs to have a certain degree of strength and water resistance; for example, vinyl can be used.

A water inlet pipe 8 is fixed at a suitable location near the outer periphery of the float plate 18 so as to penetrate perpendicularly to the surface.
The outlet of the water inlet pipe 8 opens toward the first part 16 at the lower side of the float plate 18 . Therefore tube 7
And water from the ground supplied through the water inlet pipe 8 is injected into the bag 20. The bag 20 flexibly changes its volume under the sea surface in response to water injection. Because seawater and freshwater have different specific gravity,
Depending on the water depth of the bag 20, a portion of the water inside the bag 20 is
It is pushed up into the cylinder 19.

Near the bottom of the exposed side surface of the cylinder 19, a water outlet pipe 10 vertically penetrates the side surface and is fixed thereto.
Therefore, the water 24 in the second portion 17 flows through the water outlet pipe 1
0 and to the ground through pipe 12.

FIG. 4 is a schematic sectional view showing the principle of water supply in the water storage tank shown in FIG. 3. In the figure, the sea level is indicated by a dashed line. The water supply station 4 is installed at an altitude of h3 meters above sea level. Water is supplied to the bag 20 through the water supply pipe 5 due to potential energy. The bag 20 flexibly changes its volume depending on the water supply. Now, 20 bags
Suppose that the water depth in the cylinder 19 is h2 meters, and the water level pushed up into the cylinder 19 is h1 meters. For simplicity, if we assume that the specific gravity of water is 1 and the specific gravity of seawater is 1.1, then the following equation holds true due to pressure balance.

1×(h1+h2)=1.1×h2 Therefore, the water level h1 inside the cylinder 19 is expressed by the following equation.

h1=0.1×h2 In this way, the inside of the cylinder 19 is 1/of the water depth of the bag 20.
The water is pushed up to the water level of 10. In principle,
Natural water supply is possible as long as h3 > h1.

FIG. 5 is a schematic cross-sectional view showing the principle of drainage in the water storage tank shown in FIG. 3. As in Fig. 4, the sea surface is indicated by a dashed line. Drainage field 14 exists at an altitude of h4 meters above sea level.
The water level inside cylinder 19 has been pushed up to h1 meter. Now, assuming that h1>h4, the water 24 in the cylinder 19 is supplied to the drainage field 14 through the drain pipe 11 only by potential energy. In principle, natural drainage is possible as long as h1 > h4.

Although h1 becomes smaller due to drainage, the flexible bag 20 contracts accordingly, and h2 also becomes smaller. Finally, at the time of h1=h4, h2=10h4,
Natural drainage due to potential energy becomes impossible. Therefore, it is necessary to use a pump for subsequent drainage.

In addition, in the underwater water storage tank explained above, only natural water supply and natural drainage have been described. However, if necessary, a pump for water supply and drainage may be provided.

It should be understood that the water storage tank 19 shown in FIG. 3 is merely an example for illustrative purposes. For example, the mounting positions of the water inlet pipe 18 and the water outlet pipe 10 may be changed as appropriate. Also, the second part 17
The cross-sectional area of may be made small to reduce water evaporation. Further, the second portion 17 may have the same cross-sectional area as the first portion 16 and may be connected to the first portion 16. In this case, a hard material may be used for the side surfaces of the continuous first and second portions, and the bottom may be a piston that moves up and down freely depending on the amount of water stored. Furthermore, a simple lid may be provided at the upper end of the cylinder 19 to prevent water from evaporating and dust from entering.

The underwater water tank described above is not limited to the above-mentioned uses, and can be used for many purposes. For example, the upper surface of the float plate 18 can be used to create a marine leisure land. The stored fresh water is
For example, it can be used as a freshwater pool. It is also possible to farm freshwater fish, and it may also be possible to farm salmon and other fish by taking advantage of the presence of both freshwater and seawater. If equipped with water purification equipment, it can also be used as a water supply station for ships. If an outlet is provided at the bottom of the bag 20, river sand may be collected. It is thought that such uses will be realized as a secondary to the above-mentioned uses as various water sources.

FIG. 1 is a schematic diagram showing an embodiment of the present invention applied to an underwater water tank as described above. In the figure, a first portion 16 of the water storage tank 9 below the sea level
Around the net 21, a plurality of stages (three stages in the figure) of hoisting machines 30 are arranged at appropriate intervals. FIG. 7 is a schematic cross-sectional view taken along line A-A in FIG. 1, and as shown in FIG.
The hoists 30 at each stage are provided at predetermined angle intervals (at 45° intervals in FIG. 7) along the outer periphery of the net 21. In addition, in Figure 1, for the sake of simplifying the drawing,
Only the hoists 30 provided at 180° opposing positions are shown. Each hoist 30 may be provided with a float to reduce the load its weight places on the net 21. Alternatively, each hoist 30 may be supported by hanging a rope from the float plate 18. Each hoist 30 is connected to one end of a rope means 31 . This rope means 31 is for mooring the water storage tank 9, and various materials can be selected for the rope means 31. For example, a so-called rope may be used, or a wire or chain may be used. The other end of each rope means 31 is connected to an anchor 32 fixed to the seabed 33. As will be described later, each hoist 30 functions to hoist the rope means 31 in response to changes in the tidal current, thereby deforming the first portion 16 of the water storage tank 9 and reducing its fluid resistance. Therefore,
When the hoist 30 performs the hoisting operation, the net 2
1 is loaded. This load is
Since the first portion 16 acts intensively on the portion where the zero is provided, there is a possibility that the first portion 16 may be distorted. Therefore, a band member 34 is provided in the net 21 in parallel with the weft thread 22 so as to connect the winding machines 30 of each stage. This band member 34 acts to disperse the load that the net 21 receives from the hoist 30 in the circumferential direction, and is preferably made of corrosion-resistant metal.

FIG. 6 is a schematic block diagram of an electrical circuit for controlling the hoist 30 shown in FIG. In the figure, a tidal current sensor 35 is for detecting the direction and speed of the tidal current around the water storage tank 9. The output of the tidal current sensor 35 is given to a hoisting controller 36. This hoisting controller 36 is for controlling the operation of each hoisting machine 30, and includes, for example, a microcomputer. A winding amount table 37 is connected to the winding controller 36 . This winding amount table 3
7 is constituted by a nonvolatile memory, and stores the optimum hoisting amount of each hoisting machine 30 for each combination of the direction and speed of the current. The winding amount set in the winding amount table 37 is determined in advance through simulation or the like.

Next, the operation of the embodiment shown in FIGS. 1 and 6 will be explained.

FIG. 8 is a schematic cross-sectional view taken along line A--A in FIG. In order to make the explanation easier to understand, each hoisting machine 30 is given a reference number 30a to 30h, and each rope means 31 is given a reference number 31a to 31h. Assuming that the tide is now flowing in the direction of the arrow 38, the tidal current sensor 35 detects the direction and speed of this tidal current. The hoisting controller 36 reads the detection results of the tidal current sensor 35,
A predetermined area of the winding amount table 37 corresponding to this detection result is searched. The optimum hoisting amount for each hoisting machine 30a to 30h is read from this searched area and taken into the hoisting controller 36. The hoisting controller 36 controls the hoisting amount of each hoisting machine 30a to 30h based on the optimum hoisting amount read from the hoisting amount table 37. In the case of FIG. 8, the hoists 30c and 30h hoist the rope means 31c and 31h by a predetermined amount, and the other hoists let out the corresponding rope means by a predetermined amount. As a result, the net 21 is deformed into a substantially elliptical shape along the direction 38 of the tidal current, as shown in FIG. Therefore, the first
The fluid resistance of the portion 16 is significantly reduced compared to the circular case. As a result, the force that the water storage tank 9 receives from the tidal current is significantly reduced compared to the case where the water storage tank 9 is circular, and it becomes possible to securely moor the water storage tank 9 even against rapid tidal flow. Further, the influence that the water storage tank 9 has on the direction of the tidal current is less than that in the case of a circular shape, and the problem of environmental changes caused by fluctuations in the direction of the tidal current is also solved.

When the direction and speed of the current change, the corresponding optimal hoisting amount for each hoisting machine is read out from the hoisting amount table 37, and the hoisting controller 36 controls the hoisting amount for each hoisting machine based on the read hoisting amount. do. In this way, the hoisting controller 36 controls the direction and degree of deformation of the net 21 depending on the direction and speed of the current. It should be noted that when a wave-ratio alarm is issued, it is preferable to control the amount of winding so that the degree of deformation of the net 21 is maximized. In this case, in order to prevent the water in the bag 20 from overflowing from the second portion 17 of the water storage tank 9, it is recommended not to fill the bag 20 with water to the full, but to always leave some room. preferable.

In addition, according to the embodiment described above, the first portion 16 of the water storage tank 9 is deformed by winding up the mooring rope means 31a to 31h.
As shown in the figure, a hoist 40 is also installed inside the bag 20.
a to 40h may be provided, and rope means 41a to 41b stretched diagonally between these may be controlled to wind up to help deform the water storage tank 9.

Further, in the embodiment described above, the net 21 has a mesh structure formed by the weft threads 22 and the warp threads 23, but as shown in FIG.
It may also be a mesh structure with threads extending upward to the right and threads extending upward to the left. When a net with a mesh structure as shown in Fig. 10 is used, the hoist 3
The load applied to the net by winding the rope means 31 is distributed in the diagonally upper right direction, diagonally lower left direction, diagonally upper left direction, and diagonally lower right direction. Member 34 would be unnecessary.

Further, in the above embodiment, the other end of each rope means 31 is fixed to the seabed, but a support may be erected on the seabed and the other end of the rope means 31 may be fixed to this support.

[Effect of the Invention] As described above, according to the present invention, the underwater portion of the underwater tank is deformed according to the direction and speed of the tidal current, so that the tidal current is strong and its direction changes. Undersea water tanks can be reliably moored in a fixed location even under adverse conditions. Furthermore, since the underwater water tank is deformed along with the flow of the tide, it does not change the direction of the tide and has extremely little negative impact on the environment.

[Brief explanation of the drawing]

FIG. 1 is a diagram showing a schematic configuration of an embodiment of the present invention. FIG. 2 is an explanatory diagram showing a preferred example of an underwater water tank to which the present invention is applied. FIG. 3 is a schematic perspective view showing a preferred example of the water storage tank 9. FIG. 4 is a schematic sectional view showing the principle of water supply to the water storage tank shown in FIG. 3. FIG. 5 is a schematic sectional view showing the principle of drainage of the water storage tank shown in FIG. 3. Figure 6 shows the hoisting machine 3 shown in Figure 1.
1 is a schematic block diagram showing an electric circuit for controlling 0. FIG. 7 is a schematic cross-sectional view taken along line A-A shown in FIG. FIG. 8 is a schematic sectional view for explaining the operation of the embodiment shown in FIGS. 1 and 6. FIG. FIG. 9 is a schematic sectional view showing another embodiment of the invention. FIG. 10 is a diagram showing another embodiment of the net 21. In the figure, 9 is a water storage tank, 21 is a net,
30 is a hoist, 31 is a rope means, 32 is an anchor, 34 is a band member, 35 is a tidal current sensor, 36
is a winding controller, and 37 is a winding amount table.

Claims (1)

[Scope of Claims] 1. A device for mooring an underwater water tank that provides water storage means in the sea, temporarily stores water supplied from the ground in the water storage means, and supplies water to the ground again. The submerged portion of the underwater water tank is made of a flexible material, one end of each of which is connected around the submerged portion of the underwater tank, and the other end of each of which is connected to a fixed portion. a mooring rope means fixed to the underwater tank; a hoisting means provided for each rope means for hoisting each rope means; and a means for detecting the direction and speed of the tidal current of seawater surrounding the underwater water tank. tidal current detection means, and controlling the amount of hoisting of each of the hoisting means based on the detection results of the tidal current detection means, and deforming at least the submerged portion of the underwater water tank so as to reduce fluid resistance against the tidal current. A mooring device for an underwater water tank, comprising a control means for 2. The underwater water tank according to claim 1, wherein the underwater water tank is formed in a cylindrical shape, and each of the rope means is provided at a predetermined angle around the outer circumference of the cylindrical water tank. mooring device. 3. The second aspect of claim 2, wherein a band-like member is formed on the outer periphery of the underwater water tank for distributing the load applied from each of the rope means in the circumferential direction.
A mooring device for an underwater water tank as described in Section 1. 4. The mooring device for a seawater storage tank according to any one of claims 1 to 3, wherein the fixed part to which the other end of each rope means is connected is the seabed. 5. The mooring device for a seawater tank according to any one of claims 1 to 3, wherein the fixed part to which the other end of each rope means is connected is a support erected on the seabed.