JP6816975B2 - Wave-making device and wave-making method - Google Patents

Description

The present invention relates to a wave-making device and a wave-making method. More specifically, the present invention continuously creates a rising waveform (bore) and a long-period wave (long-period wave) at the tip of a tsunami waveform, and actually creates an actual wave. It relates to a wave-making device and a wave-making method capable of reproducing a wave close to a tsunami.

Most of the causes of tsunamis are caused by submarine earthquakes in the sea area, and on a horizontal scale, displacement of the sea surface of several meters occurs in the range of several tens to 100 km and propagates throughout the sea area. Therefore, the period of the tsunami is very long, from several minutes to several tens of minutes, and when the tip of the tsunami reaches the shallow sea area, the wave height increases sharply and a bore is generated at the tip.

Conventionally, when conducting a hydraulic experiment targeting a tsunami, a piston-type or pump-type wave-making device has been used (see, for example, Patent Document 1). However, with the conventional wave-making device, it is difficult to simultaneously reproduce the rising waveform at the tip of the tsunami waveform and the wave with a long period. For example, in the piston type, the wave-making plate is moved in a long period to generate waves, but when reproducing a wave with a large wave height such as a tsunami, it is necessary to move the wave-making plate over a long distance, which is a large scale. Facilities are needed. Therefore, we have only conducted hydraulic experiments targeting only the rising waveform at the tip of the tsunami waveform by creating long-period sine waves and solitary waves.

The pump type can generate long-period waves, but it is difficult to create a waveform that rises sharply due to the characteristics of the pump, and when creating a wave with a large wave height such as a tsunami. Requires a large capacity pump. As described above, with the conventional wave-making method, a large-scale facility is required to reproduce a wave close to a tsunami, so it is difficult to reproduce a wave close to a tsunami and perform a hydraulic experiment. Therefore, a wave-making device and a wave-making method that can reproduce waves close to a tsunami without requiring a large-scale facility have been desired.

Japanese Unexamined Patent Publication No. 2013-181869

An object of the present invention is to continuously generate a rising waveform (bor) at the tip of a tsunami waveform and a long-period wave (long-period wave) to reproduce a wave close to an actual tsunami. To provide equipment and wave-forming methods.

In order to achieve the above object, the wave-making device of the present invention is installed inside the water tank in which the object to be measured is arranged and inside the water tank at intervals in the longitudinal direction of the water tank with respect to the object to be measured. The water storage unit is provided with a partition plate forming a surface of the water storage unit on the measurement object side, and a moving mechanism for moving the partition plate up and down, and the water storage unit opened by moving the partition plate upward. In a wave-making device that generates waves by water in the water storage unit that has flowed out from the measurement target side toward the measurement target, a circulation means that circulates the discharged water to the water storage unit and the above. A control unit that controls the vertical movement of the partition plate, a wave height sensor that detects the wave height between the partition plate and the measurement object, and the water tank having an upper bottom surface and a lower bottom surface. The water storage portion formed in a heavy bottom structure, the measurement object and the water storage portion are arranged on the upper bottom surface, and the water storage portion formed between the upper bottom surface and the lower bottom surface, and the longitudinal direction of the upper bottom surface. The data detected by the wave height sensor is provided with vertically penetrating communication portions formed at both ends, and the water flowing into the water storage portion through the communication portion is circulated to the water storage portion by the circulation means. By controlling the vertical movement of the partition plate based on the predetermined waveform data, the outflowing water generates a wave having a waveform similar to the predetermined waveform data inside the water tank. It is characterized by letting it.
Another wave-making device of the present invention includes a water tank in which the object to be measured is arranged inside, and a water storage unit installed inside the water tank at intervals in the longitudinal direction of the water tank with respect to the object to be measured. A partition plate forming a surface of the water storage unit on the measurement target side and a moving mechanism for moving the partition plate up and down are provided, and the water storage unit is opened on the measurement target side by the upward movement of the partition plate. In a wave-making device that generates waves by the water in the water storage unit that has flowed out from the water to the measurement target, the circulating means that circulates the discharged water to the water storage unit and the vertical movement of the partition plate. A control unit for controlling the water and a wave height sensor for detecting the wave height between the partition plate and the measurement object are provided, and water in the water storage unit overflows to a side facing the partition plate. The water level of the water storage unit is maintained constant, and the vertical movement of the partition plate is controlled based on the detection data by the wave height sensor and the waveform data determined in advance. It is characterized in that water is used to generate a wave having a waveform similar to the predetermined waveform data inside the water tank.
Yet another wave-making device of the present invention includes a water tank in which the object to be measured is arranged inside, and a water storage unit installed inside the water tank at intervals in the longitudinal direction of the water tank with respect to the object to be measured. A partition plate constituting the surface of the water storage unit on the side of the measurement object and a moving mechanism for moving the partition plate up and down are provided, and the measurement object of the water storage unit opened by the upward movement of the partition plate. In a wave-making device that generates waves by the water in the water storage unit that has flowed out from the side toward the measurement object, the circulating means that circulates the discharged water to the water storage unit and the upper and lower parts of the partition plate. A control unit that controls movement, a wave height sensor that detects the wave height between the partition plate and the measurement object, and a wave height sensor that detects the wave height between the partition plate and the measurement object are provided on the downstream side of the measurement object in the outflow direction. The movable weir is provided with a wave height sensor that detects the water level between the measurement object and the movable weir, and the water is stored at a predetermined water level between the measurement object and the movable weir. The water in the water storage unit is flowed toward the measurement object and flows between the object and the movable weir, and the discharged water is passed through the movable weir and circulated to the water storage part. At the same time, the water level between the measurement object and the movable weir can be changed by the movable weir, and the detection data by the wave height sensor between the partition plate and the measurement object and the predetermined value are determined in advance. By controlling the vertical movement of the partition plate based on the waveform data, the outflowed water generates a wave having a waveform similar to the predetermined waveform data inside the water tank, and the said The wave height sensor that detects the water level between the object to be measured and the movable weir detects the water level between the two, and this detection data and the generated wave are used between the object to be measured and the movable weir. Based on predetermined predetermined water level data to be reproduced between the two when water flows into the water, the movable dam controlled by the control unit stores the water between the measurement object and the movable dam. It is characterized in that the water is controlled to the predetermined water level.

In the wave-making method of the present invention, a measurement object and a water storage portion are arranged inside the water tank at intervals in the longitudinal direction of the water tank, and a partition plate constituting the surface of the water storage portion on the measurement target side is provided. A wave-making method in which the measurement target side of the water storage unit is opened by moving upward to allow water in the water storage unit to flow out toward the measurement target, and the discharged water generates a wave. In the above, the water tank has a double bottom surface structure having an upper bottom surface and a lower bottom surface, and the measurement object and the water storage portion are arranged on the upper bottom surface, and between the upper bottom surface and the lower bottom surface. By forming a water reservoir, providing communication portions that penetrate vertically at both ends of the upper bottom surface in the longitudinal direction, and circulating the water that has flowed into the water storage portion through the communication portion to the water storage portion. The outflowed water is circulated to the water storage unit, and the wave height of the wave is detected between the partition plate and the measurement object by the wave height sensor, and the wave height is detected based on the detection data and the predetermined waveform data. By controlling the vertical movement of the partition plate, it is characterized in that the outflowed water generates a wave having a waveform similar to the predetermined waveform data.
In another wave-making method of the present invention, a measurement object and a water storage portion are arranged inside the water tank at intervals in the longitudinal direction of the water tank, and a partition constituting the surface of the water storage portion on the measurement target side is formed. By moving the plate upward, the side of the water storage unit to be measured is opened, the water in the water storage unit is discharged toward the measurement object, and the discharged water generates a wave. In the wave method, the water in the water storage section is overflowed to the side facing the partition plate to keep the water level of the water storage section constant, and the outflowed water is circulated to the water storage section. The outflow is performed by detecting the wave height of the wave between the partition plate and the measurement object by a wave height sensor and controlling the vertical movement of the partition plate based on the detection data and the predetermined waveform data. It is characterized in that a wave having a waveform close to the predetermined waveform data is generated by the water.
In yet another wave-making method of the present invention, a measurement object and a water storage unit are arranged inside the water tank at intervals in the longitudinal direction of the water tank, and a surface of the water storage unit on the measurement target side is formed. By moving the partition plate upward, the measurement object side of the water storage unit is opened to allow the water in the water storage unit to flow out toward the measurement object, and the discharged water generates a wave. In the wave-making method, a movable weir is provided on the downstream side in the outflow direction of the outflowed water from the measurement object, and the water is stored at a predetermined water level between the measurement object and the movable weir. The water in the water storage unit is flowed toward the measurement object and flows between the object and the movable weir, and the discharged water is passed through the movable weir and circulated to the water storage part. At the same time, the wave height of the wave is detected between the partition plate and the object to be measured by the wave height sensor, and the vertical movement of the partition plate is controlled based on the detection data and the predetermined waveform data. A wave height sensor that generates a wave having a waveform close to the predetermined waveform data by the outflowing water and detects the water level of water stored between the measurement object and the movable dam. Detects the water level between the two, and when water flows between the measurement object and the movable weir due to the detected data and the generated wave, a predetermined predetermined value that is desired to be reproduced between the two. By changing the vertical height of the movable weir based on the water level data of the above, the water stored between the measurement object and the movable weir is controlled to the predetermined water level. ..

According to the present invention, since the water flowing out from the water storage unit toward the measurement target is circulated in the water tank, the water can be continuously discharged toward the measurement target. Then, the wave height of the wave between the partition plate and the object to be measured is detected by the wave height sensor, and the vertical movement of the partition plate is controlled based on the detection data and the predetermined waveform data, so that the necessary waveform data can be obtained. If used, it not only generates waves of various wavelengths, periods, and wave heights, but also continuously creates rising waveforms (bore) and long-period waves (long-period waves) at the tip of the tsunami waveform. It is possible to reproduce waves that are close to the actual tsunami.

In the present invention, the water tank is formed in a double bottom structure having an upper bottom surface and a lower bottom surface, the measurement object and the water storage portion are arranged on the upper bottom surface, and between the upper bottom surface and the lower bottom surface. The formed water storage portion and the vertically penetrating communication portions formed at both ends of the upper bottom surface in the longitudinal direction are provided, and the water flowing into the water storage portion through the communication portion is circulated to the water storage portion by the circulation means. You can also. In this case, the water flowing out from the water storage part appropriately flows into the water storage part through the communication part, so that the amount of water existing on the upper bottom surface is optimized without excess or deficiency. Therefore, water can be circulated stably and continuously.

When water in the water storage unit is allowed to flow toward the measurement object in a state where water at a predetermined water level exists between the measurement object and the partition plate inside the water tank, a tsunami at sea is reproduced. be able to. When the water in the water storage unit is allowed to flow toward the measurement object in a state where there is no water between the measurement object and the partition plate inside the water tank, a tsunami flooding on land can be reproduced. Can be done.

It is also possible to maintain a constant water level in the water storage section. With this configuration, the water pressure of the flowing water becomes constant, so that stable waves can be generated.

By overflowing the water in the water storage section to the side facing the partition plate, the upper limit water level of the water storage section can be maintained constant. With this configuration, the water level of the water storage unit can be maintained constant with a very simple configuration.

A water level gauge for measuring the water level of the water storage unit may be provided, and the vertical movement of the partition plate may be controlled based on the detection data of the water level gauge. With this configuration, even when the water level of the water storage unit changes, it is possible to accurately generate a wave having a waveform that is close to the predetermined waveform data.

The partition plate may be configured to be fixed at an arbitrary position in the longitudinal direction of the water tank by a frame by interposing a rail with a bearing that extends in the vertical direction and abuts on the partition plate. With this configuration, the partition plate can be stably fixed to the water tank while the wave-making distance can be set arbitrarily. Moreover, the partition plate can be moved up and down smoothly and accurately.

The water circulated in the water storage unit may be supplied to the partition plate side by passing through a rectifying body provided in the water storage unit. With this configuration, it is possible to avoid giving waves and unnecessary turbulence caused by the flow of water circulated in the water storage unit to the water flowing out from the water storage unit toward the object to be measured. As a result, a wave having a waveform similar to the predetermined waveform data can be reproduced with higher accuracy.

The wave that rushes to the downstream side in the outflow direction of the water that has flowed out from the measurement object can be extinguished by a wave-dissipating body. With this configuration, it is possible to prevent waves that exceed the measurement target from being reflected and returned, so that more accurate measurement results can be obtained without being affected by unnecessary reflected waves.

A movable weir is provided on the downstream side in the outflow direction of the outflowed water from the measurement object, and the water level of the water stored between the measurement object and the movable weir can be changed by this movable weir. You can also do it. With this configuration, it is possible to reproduce the situation inside the breakwater when the tsunami enters the breakwater.

It is explanatory drawing which illustrates the embodiment of the wave-making apparatus of this invention in the longitudinal sectional view of a water tank. It is explanatory drawing which enlarged the vicinity of the reservoir part of FIG. It is explanatory drawing which illustrates the state of the water tank of the wave-making apparatus of FIG. 1 and the inside thereof in a plan view. It is explanatory drawing which schematically exemplifies a bore wave and a long-period wave which are generated by the wave-making apparatus of this invention in a state where water of a predetermined water level does not exist on the upper bottom surface in the longitudinal sectional view of a water tank. It is explanatory drawing which illustrates another embodiment of the wave-making apparatus of this invention in the longitudinal sectional view of a water tank. It is explanatory drawing which illustrates the state of the water tank of the wave-making apparatus of FIG. 5 and the inside thereof in a plan view. It is explanatory drawing which schematically exemplifies a bore wave and a long-period wave generated in the state which the water of a predetermined water level exists on the upper bottom surface by the wave-making apparatus of this invention in the longitudinal sectional view of the water tank. It is explanatory drawing which illustrates still another embodiment of the wave-making apparatus of this invention in the longitudinal sectional view of a water tank. It is explanatory drawing which illustrates still another embodiment of the wave-making apparatus of this invention in the longitudinal sectional view of a water tank. It is explanatory drawing which schematically exemplifies a bore generated by a conventional wave-making apparatus in a cross-sectional view in the longitudinal direction of a water tank.

Hereinafter, the wave-making device and method of the present invention will be described based on the embodiment shown in the figure.

The wave-making device 1 of the present invention illustrated in FIGS. 1 to 3 constitutes a water tank 2 in which the measurement object 8 is arranged, a water storage unit 3 arranged in the water tank 2, and side surfaces of the water storage unit 3. It includes a partition plate 4 and a moving mechanism 5 for moving the partition plate 4 up and down. The wave-making device 1 further stores a control unit 6 that controls the vertical movement of the partition plate 4, a wave height sensor 7 for which detection data is input to the control unit 6, and a water W that has flowed out from the water storage unit 3. It is provided with a circulation means 9 for circulating in 3. In the drawings, the longitudinal direction of the water tank 2 is indicated by an arrow X, and the width direction is indicated by an arrow Y.

Further, in this embodiment, the frame 10 for fixing the partition plate 4 to the water tank 2, the rail 11 with bearings interposed between the frame 10 and the partition plate 4, and the rectifying body 12 installed in the water storage unit 3 A wave-dissipating body 13 arranged in the water tank 2 and a water level gauge 14 installed above the water storage unit 3 are provided. The water storage unit 3 is arranged at one end in the longitudinal direction of the water tank 2, and the measurement object 8 is arranged at the other end in the longitudinal direction of the water tank 2.

The water tank 2 has a rectangular parallelepiped shape with an open upper surface, and has a length of, for example, 10 to 100 m, a width of 0.3 to 2.0 m, and a height of about 0.5 to 2.0 m. The width dimension is constant and the bottom surface is horizontal. The side surface of the water tank 2 is formed of, for example, transparent glass, and is appropriately reinforced with a metal member.

In this embodiment, the water tank 2 has a double bottom structure composed of an upper bottom surface 2a and a lower bottom surface 2b. The upper bottom surface 2a and the lower bottom surface 2b are horizontal to each other, and a water reservoir 2e is formed between them. Communication portions 2c and 2d penetrating vertically are provided at both ends of the upper bottom surface 2a in the longitudinal direction. A recessed portion 2f is provided at the other end of the water reservoir 2e in the longitudinal direction (on the side of the object to be measured 8).

The water storage unit 3 includes a partition plate 4 extending in the entire width direction of the water tank 2 and a side plate 3a facing the partition plate 4 and arranged at intervals in the longitudinal direction of the water tank 2. The side plate 3a extends upward from the upper bottom surface 2a and extends over the entire width direction of the water tank 2. The partition plate 4 is arranged closer to the object to be measured 8 than the side plate 3a, and when it moves downward, its lower end abuts on the upper bottom surface 2a. A part of the water tank 2 in the longitudinal direction is partitioned by the partition plate 4 and the side plate 3a, and water W is stored between them. That is, the structure is such that the water W overflows from the side plate 3a when the water level exceeds a certain level. The water storage capacity of the water storage unit 3 can be arbitrarily set.

The height dimension of the partition plate 4 is set to be equal to or larger than the height dimension of the side plate 3a. The water storage capacity of the water storage unit 3 can be changed by changing the height dimensions of the partition plate 4 and the side plate 3a.

An actuator can be used as the moving mechanism 5, and for example, an electric cylinder, a hydraulic cylinder, or the like is used. A plurality of moving mechanisms 5 may be provided.

The frame 10 includes an outer frame frame 10c having a frame structure forming a rectangular parallelepiped, a fixture 10d for fixing the outer frame frame 10c to the upper end of the water tank 2, and a flat plate-shaped endurance extending downward from the outer frame frame 10c. It is composed of a hydraulic frame 10a and a support frame 10b for fixing the moving mechanism 5 to the outer frame frame 10c. The water pressure resistant frame 10a is arranged to face the partition plate 4, and a rail 11 with a bearing extending in the vertical direction is fixed to the frame 10a. The rail 11 with bearings abuts on the partition plate 4 to guide the vertical movement of the partition plate 4.

The width dimension of the water pressure resistant frame 10a is substantially the same as the width dimension of the partition plate 4. The lower end position of the water pressure resistant frame 10a is set to a position higher than the upper end position of the opening height H1 (H2) described later of the partition plate 4.

The non-movable portion (cylinder) of the moving mechanism 5 is firmly fixed to the outer frame frame 10c by the support frame 10b. As a result, the movable portion (rod) of the moving mechanism 5 stably moves forward and backward in the vertical direction, and the partition plate 4 moves up and down accordingly.

The frame 10 is fixed by the fixture 10d at an arbitrary position with respect to the longitudinal direction of the water tank 2. As a result, the partition plate 4 can be arranged at an arbitrary position in the longitudinal direction of the water tank 2. The partition plate 4 may be fixed to the frame 10 at an arbitrary position in the longitudinal direction of the water tank 2.

The control unit 6 includes an input means and a calculation function, and the moving mechanism 5, the wave height sensor 7, and the water level gauge 14 are connected by wire or wirelessly. Waveform data of the wave to be generated is input to the control unit 6 in time series. Based on the waveform data input in advance, the wave height data sequentially input from the wave height sensor 7, and the water level data sequentially input from the water level gauge 14, the control unit 6 generates a wave of predetermined waveform data. The amount of vertical movement of the partition plate 4 required for this is calculated. Then, a command is issued to the moving mechanism 5 to move the partition plate 4 up and down by the moving amount calculated by the calculation.

As the control unit 6, a personal computer or the like having both an input means and a calculation function can be used. It is also possible to share the input means and the calculation function with different devices.

The wave height sensor 7 detects the wave height of the wave T between the partition plate 4 and the object to be measured 8. As the wave height sensor 7, an ultrasonic wave height meter, a capacitive wave height meter, or the like can be used. The wave height sensor 7 is attached, for example, via a beam hung in the width direction at the upper end of the water tank 2, and detects the wave height at the center of the wave T in the width direction.

The number of wave height sensors 7 installed may be singular or plural, but in order to grasp the state of the wave T more accurately, it is desirable to provide a plurality of wave height sensors 7 at intervals in the longitudinal direction of the water tank 2.

The measurement object 8 is an object for which the influence of the wave T is to be measured and grasped. As the object to be measured 8, a model of a factory tank, a building, or the like can be exemplified when reproducing a tsunami flooding on land. When reproducing a tsunami on the sea, a model of a revetment structure such as a breakwater can be exemplified. By using the measurement object 8 extending in the width direction or close to the width direction of the water tank 2, it is possible to acquire a wide range of data more suitable for the actual situation. By reproducing a situation close to the actual site by embankment on the upper bottom surface 2a, it is possible to obtain data more suitable for the actual situation. Since the data at the end of the water tank 2 in the width direction includes many influences such as reflection and interference, the data at the center in the width direction is used for analysis.

The circulation means 9 of this embodiment includes a water pipe 9b that connects the water storage portion 2e and the water storage portion 3, and a pump 9a that is connected to the water pipe 9b. By this circulation means 9, the water W accumulated in the water storage part 2e is absorbed from the water suction port 9c, and the water W is supplied to the water storage part 3 from the discharge port 9d provided in the upper part of the water storage part 3.

Since it is necessary to always secure the amount of water to be discharged in order to form the wave T in the water storage unit 3, it is desirable to use a pump 9a having a water supply capacity as large as possible. Alternatively, a plurality of pumps 9a may be installed. Further, for example, the pump 9a may be connected to the control device 6 by wire or wirelessly, and the amount of water supplied to the pump 9a per unit time may be changed according to the command of the control device 6. In this embodiment, the water storage unit 3 is always kept full by using the pump 9a having a large water supply capacity, and the water level of the water storage unit 3 is kept constant by overflowing the water W from the upper end of the side plate 3a. It has become.

The rectifying body 12 is a member that regulates the water flow in the water storage unit 3 to be constant. For example, a plate or the like on which a large number of through holes are formed can be used as the rectifying body 12. As the rectifying body 12, a tubular type or Ben type rectifying device can also be used. It is desirable that the rectifying body 12 is arranged at a position closer to the partition plate 4 than the discharge port 9d in order to adjust the turbulence of the water flow in the water storage unit 3 due to the influence of the water W supplied by the pump 9a.

The wave-dissipating body 13 is arranged on the downstream side in the outflow direction of the water W discharged from the water storage unit 3 with respect to the measurement object 8. When the wave T collides with the wave-dissipating body 13, the force of the wave T is dispersed, and it is possible to prevent the wave T from being reflected. The wave-dissipating body 13 may have a configuration capable of preventing the wave T from being reflected in this way. In this embodiment, a strong three-dimensional network structure made of resin is used as the wave-dissipating body 13, and the wave energy is absorbed by the voids and the roughness (roughness) of the arrangement density. The wave-dissipating body 13 may extend to the lower end of the water reservoir 2e (recessed portion 2f).

The water level gauge 14 measures the water level on the downstream side of the rectifying body 12 of the water storage unit 3. In this embodiment, the water level gauge 14 for measuring the distance to the water surface is attached to a beam hung in the width direction at the upper end of the water tank 2, but a water level gauge 14 installed inside the water storage unit 3 may also be used. it can. As the water level gauge 14, the same one as the wave height sensor 7 can be used.

When the amount of water W supplied to the water storage unit 3 is smaller than the amount of water W flowing out from the water storage unit 3, the water level of the water storage unit 3 changes. Further, even when the water W overflows from the side plate 3a, the water level on the downstream side of the rectifying body 12 of the water storage unit 3 may be lower than the upper end of the side plate 3a due to the influence of the rectifying body 12. The water level gauge 14 is not essential, but in these cases, the water level gauge 14 can accurately grasp the actual water level of the water storage unit 3.

The wave-making device 1 of the present invention can reproduce a tsunami flooded on land and a tsunami on the sea. In this embodiment, the steps of the wave-making method for reproducing the tsunami flooded on land are as follows. explain.

When reproducing the tsunami flooded on land, the measurement object 8 is arranged at a predetermined position on the upper bottom surface 2a. If necessary, reproduce the situation at the site by embankment. The waveform data of the wave to be reproduced is input to the control unit 6. The partition plate 4 is fixed at a predetermined position in the water tank 2 by the frame 10. A sufficient amount of water W is stored in the water storage unit 3 in a state where the lower end of the partition plate 4 is in contact with the upper bottom surface 2a so that the water W overflows from the side plate 3a.

After completing the above preparations, a command to start the experiment is input to the control unit 6. When a command to start an experiment is input to the control unit 6, a command to move the partition plate 4 upward to an opening height H1 suitable for generating a predetermined wave is input from the control unit 6 to the moving mechanism 5. .. As a result, the partition plate 4 is moved upward along the hydraulic pressure-resistant frame 10a via the rail 11 with bearings by the moving mechanism 5. The water W in the water storage unit 3 is discharged from the opening formed by the upward movement of the partition plate 4. The water W flowing out from the water storage unit 3 flows on the upper bottom surface 2a toward the measurement object 8 to form a wave T.

The wave height of the wave T is sequentially detected by the wave height sensor 7, and the detected wave height data is sequentially input to the control unit 6. The control unit 6 calculates an appropriate opening height H1 based on the detection data input from the wave height sensor 7, the detection data input from the water level gauge 14, and the waveform data determined in advance, and the calculated opening height is calculated. The amount of water flowing out is controlled by sequentially controlling the vertical movement of the partition plate 4 so as to be H1.

ここでＱは流出させる水の流量、Ｃｃは収縮係数、ａは仕切り板４の開口高さＨ１、Ｂは流出幅（仕切り板４の幅）、ｈ_０は貯水部３の水深、ｇは重力加速度である。 The opening height H1 of the partition plate 4 when the water W in the water storage unit 3 flows out toward the measurement object 8 in the absence of water on the upper bottom surface 2a is, for example, free outflow from the sluice gate. It is determined based on the following flow rate equation (1) modeled.

Here, Q is the flow rate of the water to be discharged, Cc is the contraction coefficient, a is the opening height H1 of the partition plate 4, B is the outflow width (width of the partition plate 4), h ₀ is the water depth of the water storage unit 3, and g is gravity. Acceleration.

By sequentially repeating the wave height detection by the wave height sensor 7, the water level detection by the water level gauge 14, and the vertical movement control of the partition plate 4 by the control unit 6, a wave T having a waveform similar to the waveform data determined in advance is reproduced. It becomes possible to do. Therefore, it is possible to generate waves having various wavelengths, periods, and wave heights. It is also possible to generate long-period waves as described later. The wave T travels on the upper bottom surface 2a and eventually collides with the measurement object 8 arranged on the downstream side on the upper bottom surface 2a. According to the purpose of the experiment, the data of the situation where the wave T and the measurement object 8 collide with each other is recorded and analyzed.

The wave T that collides with the measurement object 8 and exceeds the measurement object 8 is extinguished by the wave-dissipating body 13 and then flows into the water storage portion 2e (recessed portion 2f) through the communication portion 2c. The water W that has flowed into the water storage portion 2e (recessed portion 2f) is absorbed by the pump 9a from the water suction port 9c through the water pipe 9b, and is supplied to the water storage section 3 again from the discharge port 9d. In this way, the water W in the water tank 2 is circulated by repeating the above steps from flowing out from the water storage unit 3 to returning to the water storage unit 3.

A method of simultaneously reproducing the rising waveform (bore) of the tip of the tsunami waveform and the long-period wave (long-period wave) by the wave-making device 1 will be described below.

In the conventional wave-making device, as shown in FIG. 10, by moving the partition plate 4 upward, the water W of the water storage unit 3 is discharged to generate the bore T1. However, since only the amount of water stored in the water storage unit 3 can flow out and the vertical movement control of the partition plate 4 is not performed, a long-term stable long-period wave cannot be reproduced.

On the other hand, in this wave-making device 1, water W is continuously supplied to the water storage unit 3 by the circulation means 9. Therefore, the water W of the water storage unit 3 is not exhausted even after the partition plate 4 is opened to generate the bore T1.

If the wave waveform data to be reproduced is input to the control unit 6, the partition plate 4 is divided into the detection data of the wave height sensor 7, the detection data input from the water level gauge 14, and the predetermined wave waveform data. By moving the partition plate 4 up and down based on the above, the water W can be continuously discharged while changing the opening height H1. As a result, as illustrated in FIG. 4, a long-period wave T2 can be generated. Therefore, the wave-making device 1 of the present invention simultaneously generates a rising waveform (bore T1) at the tip of a tsunami waveform such as a tsunami and a long-period wave (long-period wave T2), and the tsunami replaces the pulling wave. It is possible to reproduce the state of half a cycle up to.

In this embodiment, since the water W in the water storage unit 3 is discharged toward the measurement object 8 in the state where the water W does not exist on the upper bottom surface 2a, it is possible to reproduce the tsunami flooding on land. ..

Since the water tank 2 is formed in a double bottom structure and the communication portions 2c and 2d and the water storage portion 2e are provided, the water W flowing out from the water storage unit 3 appropriately reaches the water storage portion 2e through the communication portions 2c and 2d. Inflow. Therefore, the water W does not overflow on the upper bottom surface 2a. Since the water W accumulated in the water reservoir 2e and the water W on the upper bottom surface 2a are separated and not continuous by adopting the double bottom surface structure, they do not interfere with each other. Further, the water W overflowing from the side plate 3a flows into the water storage portion 2e through the communication portion 2d. In this way, the water reservoir 2e functions as a buffer, and the amount of water W existing on the upper bottom surface 2a is optimized without excess or deficiency. Therefore, the water W can be circulated stably and continuously.

Since the water storage unit 3 is provided with a side plate 3a having a structure in which water overflows when the water level exceeds a certain level, the water level of the water storage unit 3 can be maintained constant with a simple structure. When the water level of the water storage unit 3 is maintained constant, the water pressure of the flowing water W becomes constant, so that a stable wave T can be generated.

Since the partition plate 4 is configured to be fixed at an arbitrary position in the longitudinal direction of the water tank 2 by the frame 10, the wave-making distance can be freely set. Further, since the partition plate 4 has a structure in which the water pressure resistant frame 10a receives the water pressure received from the water W in the water storage unit 3 and the rail 11 with a bearing is interposed, the partition plate 4 can move up and down smoothly. Can be done accurately. The rail 11 with bearings is very useful because it requires a minute and rapid vertical movement of the partition plate 4 in order to generate a long-period wave.

Further, since the water W circulated in the water storage unit 3 is supplied to the partition plate 4 side through the rectifying body 12, waves and unnecessary turbulence caused by the flow of the water W circulated in the water storage unit 3 It is advantageous to avoid giving the water W in the water storage unit 3 flowing out from the water storage unit 3 toward the measurement object 8. This is advantageous for more accurately reproducing the wave T having a waveform that approximates the predetermined waveform data.

Since the wave T that rushes to the downstream side of the measurement object 8 is extinguished by using the wave-dissipating body 13, it is necessary to prevent the wave T that exceeds the measurement object 8 from being reflected and returning. It has become an advantage. Therefore, more accurate measurement results can be obtained without being affected by unnecessary reflected waves. In this embodiment, since the wave T that is rushing to the downstream side is further dropped toward the lower bottom surface 2b to extinguish the wave, it is more advantageous to eliminate the influence of the unnecessary reflected wave.

Further, since the detection data by the water level gauge 14 is also taken into consideration when controlling the vertical movement of the partition plate 4, even when the water level of the water storage unit 3 changes, the waveform approximates the predetermined waveform data. The wave T having the above can be generated with high accuracy.

The wave-making device 1 illustrated in FIGS. 5 to 6 is provided with a weir 15 on the upper bottom surface 2a of the wave-making device 1 illustrated in FIGS. Other configurations are substantially the same as those of the wave-making device 1 shown in FIGS.

The weir 15 is arranged at a predetermined position between the partition plate 4 and the communication portion 2c, extends upward from the upper bottom surface 2a, and extends over the entire width direction of the water tank 2. The sea is reproduced by filling the area partitioned by the partition plate 14 and the weir 15 with water W. In this embodiment, a plate-shaped weir 15 is installed at the end on the communication portion 2c side of the upper bottom surface 2a.

The process of the wave-making method when reproducing a tsunami on the sea using this wave-making device 1 will be described below. The preparatory stage until the command to start the experiment is input to the control unit 6 and the flow rate formula for determining the opening height H2 of the partition plate 4 are different from the case of reproducing the tsunami flooding on land, but the same is true in other cases. is there.

In the preparatory stage, first, the measurement object 8 is arranged at a predetermined position on the upper bottom surface 2a. If necessary, reproduce the condition of the seabed at the site with sand. The waveform data of the wave to be reproduced is input to the control unit 6. The partition plate 4 is fixed at a predetermined position in the water tank 2 by the frame 10. A sufficient amount of water W is stored in the water storage unit 3 in a state where the lower end of the partition plate 4 is in contact with the upper bottom surface 2a.

With the lower end of the partition plate 4 in contact with the upper bottom surface 2a, water W is applied to the water depth D corresponding to the water depth on the sea to be reproduced in the range partitioned by the weir 15 and the partition plate 4. Then, after the water surface becomes stable, a command to start the experiment is input to the control unit 6 to start the experiment. After that, it is the same as the embodiment shown in FIGS. 1 to 3.

ここでＱは流出させる水の流量、Ｃｃは収縮係数、ａは仕切り板４の開口高さＨ２、Ｂは流出幅（仕切り板４の幅）、ｈ_０は貯水部３の水深（上流側水深）、ｈ_１は水深Ｄ（下流水深）、ｇは重力加速度である。 The opening height H2 of the partition plate 4 when the water W in the water storage unit 3 is discharged toward the measurement object 8 in the state where the water W is present on the upper bottom surface 2a is, for example, the outflow from the sluice gate. Is determined based on the following flow rate equation (2) modeled on.

Here, Q is the flow rate of the water to be discharged, Cc is the contraction coefficient, a is the opening height H2 of the partition plate 4, B is the outflow width (width of the partition plate 4), and h ₀ is the water depth of the water storage unit 3 (upstream water depth). ), H ₁ is the water depth D (downstream water depth), and g is the gravitational acceleration.

In this embodiment, the water W in the water storage unit 3 flows out toward the measurement object 8 in a state where the water W at a predetermined water level exists on the upper bottom surface 2a, so that it looks like a tsunami as shown in FIG. It is possible to simultaneously generate a rising waveform (bore T1) at the tip of a tsunami waveform and a long-period wave (long-period wave T2), and reproduce the half-period state until the marine tsunami replaces the pulling wave. ..

In this embodiment, the water W is stretched in the range partitioned by the weir 15 and the partition plate 4, but the measurement object 8 extending over the entire width direction of the water tank 2 is used to partition the measurement object 8. It is also possible to fill the area partitioned by the plate 14 with water W. In this case, the sea can be reproduced without providing the weir 15.

The water tank 2 does not have a double bottom structure, but may have a normal bottom surface as shown in FIG. In this embodiment, a tank 16 for temporarily storing the water W flowing out from the water storage unit 3 is provided at the other end of the bottom surface of the water tank 2 in the longitudinal direction (measurement target 8 side), and the tank 16 and the water storage unit 3 are provided. Is configured to circulate water W by connecting with a water pipe 9b. In this case, it is advisable to set the allowable amounts of the water storage unit 3 and the tank 16 to be large.

As shown in FIG. 8, if the bottom surface of the water tank 2 is provided with a gentle gradient and a wave T is generated on the bottom surface, the soliton split wave can be reproduced. The soliton split wave is a phenomenon in which a tsunami splits into a plurality of short-period waves and the wave height is amplified depending on conditions such as waveform and water depth.

The wave-making device 1 illustrated in FIG. 9 is provided with a movable weir 17 on the upper bottom surface 2a of the wave-making device 1 illustrated in FIGS. The object to be measured 8 is arranged between the partition plate 4 and the movable weir 17.
Further, wave height sensors 7a and 7a for measuring the water level between the object to be measured 8 and the movable weir 17 are provided. Other configurations are the same as those of the wave-making device 1 shown in FIGS.

The movable weir 17 is arranged at a predetermined position between the partition plate 4 and the communication portion 2c, and extends over the entire length of the water tank 2 in the width direction. In this embodiment, a plate-shaped movable weir 17 is installed at the end on the communication portion 2c side of the upper bottom surface 2a. The lower end of the movable weir 17 and the upper bottom surface 2 are connected by a hinge portion 17b, and the upper end portion 17a of the movable weir 17 is lifted from above the water tank 2 by a lifting portion 17c via a rod, a wire, or the like. The lifting portion 17c has a mechanism capable of changing the lifting height of the upper end portion 17a, and the lifting portion 17c moves a rod, a wire, or the like up and down to change the vertical height of the upper end portion 17a. In this embodiment, the lifting unit 17c is connected to the control unit 6 by wire, and the control unit 6 controls the movement of the lifting unit 17c to control the vertical height of the tip portion 17a of the movable weir 17. It has become.

For example, the movable weir 17 can be configured to change the vertical height of the upper end portion 17a of the movable weir 17 by rotationally driving the hinge portion 17b with a hydraulic cylinder, an air cylinder, a hydraulic motor, an electric motor, or the like. The wave height sensors 7a and 7a are connected to the control unit 6 by wire.

In this wave-making device 1, water W is stored in a range partitioned by a measurement object 8 and a movable weir 17, which are regarded as a breakwater, so that the situation inside the breakwater when a tsunami enters the breakwater is reproduced. The process of the wave-making method will be described below. The preparatory stage until the command for starting the experiment is input to the control unit 6 and the flow rate formula for determining the opening height H2 of the partition plate 4 are the same as those in the above-described embodiment.

In the preparatory stage, first, the measurement object 8 extending over the entire width direction of the water tank 2 is arranged at a position upstream of the movable weir 17 on the upper bottom surface 2a. If necessary, reproduce the situation on the seabed and near the breakwater at the site with sand.

The waveform data of the wave to be reproduced and the water level data inside the bank (between the measurement object 8 and the movable weir 17) to be reproduced are input to the control unit 6. The partition plate 4 is fixed at a predetermined position in the water tank 2 by the frame 10. A sufficient amount of water W is stored in the water storage unit 3 in a state where the lower end of the partition plate 4 is in contact with the upper bottom surface 2a.

With the lower end of the partition plate 4 in contact with the upper bottom surface 2a, water W is applied to the water depth D corresponding to the water depth on the sea to be reproduced in the range partitioned by the measurement object 8 and the partition plate 4. The vertical height of the tip portion 17a of the movable weir 17 is set to the water level D1 in the breakwater to be reproduced, and water W is filled in the range partitioned by the measurement object 8 and the movable weir 17. Then, after the water surface becomes stable at the water level D1, a command for starting the experiment is input to the control unit 6 to start the experiment.

The subsequent step of forming the wave T is the same as that of the above-described embodiment, but in this embodiment, the wave T moves beyond the measurement target 8 to the measurement target 8 in the control unit 6. Predetermined water level data to be reproduced when flowing into the weir 17 is input in advance. Then, the movable weir 17 is sequentially controlled based on the detection data input from the wave height sensor 7a and the predetermined water level data input in advance. As a result, the water level between the object to be measured 8 and the movable weir 17 is maintained at a predetermined water level that has been input in advance.

In this embodiment, the water level D1 of the water W existing between the measurement object 8 and the movable weir 17 is controlled by the movable weir 17 to reproduce the situation inside the breakwater when the tsunami enters the breakwater. be able to. Since it is possible to reproduce the situation of overflow when the breakwater is damaged and the state of scouring of the mound inside the breakwater, it is useful for verifying the cause of damage to the breakwater and examining the design of the breakwater.

1 Wave generator 2 Water tank 2a Upper bottom surface 2b Lower bottom surface 2c, 2d Communication part 2e Reservoir part 2f Depression part 3 Water storage part 3a Side plate 4 Partition plate 5 Movement mechanism 6 Control part 7, 7a Wave height sensor 8 Measurement target 9 Circulation Means 9a Pump 9b Water inlet 9c Water intake 9d Discharge port 10 Frame 10a Water pressure resistant frame 10b Support frame 10c Outer frame frame 10d Fixture 11 Bearing rail 12 Rectifier 13 Wave absorber 14 Water level gauge 15 Weir 16 Tank 17 Movable weir 17a Upper end 17b Weir 17c Lifting part W Water T wave T1 bore T2 Long periodic wave

Claims (18)

A water tank in which the measurement object is arranged, a water storage unit installed inside the water tank at intervals in the longitudinal direction of the water tank with respect to the measurement object, and a water storage unit on the measurement object side of the water storage unit. A partition plate constituting the surface and a moving mechanism for moving the partition plate up and down are provided, and the water storage portion opened by the upward movement of the partition plate is allowed to flow out from the measurement target side toward the measurement target. In a wave-making device that generates waves by the water in the water storage section of the octopus
A circulation means for circulating the discharged water to the water storage unit, a control unit for controlling the vertical movement of the partition plate, and a wave height sensor for detecting the wave height between the partition plate and the measurement object. The water tank is formed into a double bottom surface structure having an upper bottom surface and a lower bottom surface, and the measurement object and the water storage portion are arranged on the upper bottom surface, and the upper bottom surface and the lower bottom surface are arranged. A water reservoir formed between the two, and a vertically penetrating communication portion formed at both ends of the upper bottom surface in the longitudinal direction are provided, and the water flowing into the water storage portion through the communication portion is circulated by the circulation means. By controlling the vertical movement of the partition plate based on the detection data by the wave height sensor and the waveform data determined in advance, the water that has flowed out can be used to enter the inside of the water tank. , A wave-making device, characterized in that a wave having a waveform similar to the predetermined waveform data is generated. A water tank in which the measurement object is arranged, a water storage unit installed inside the water tank at intervals in the longitudinal direction of the water tank with respect to the measurement object, and a water storage unit on the measurement object side of the water storage unit. A partition plate constituting the surface and a moving mechanism for moving the partition plate up and down are provided, and the water storage portion opened by the upward movement of the partition plate is allowed to flow out from the measurement target side toward the measurement target. In a wave-making device that generates waves by the water in the water storage section of the octopus
A circulation means for circulating the discharged water to the water storage unit, a control unit for controlling the vertical movement of the partition plate, and a wave height sensor for detecting the wave height between the partition plate and the measurement object. By overflowing the water in the water storage unit to the side facing the partition plate, the water level of the water storage unit is maintained constant, and the detection data by the wave height sensor and the predetermined value are determined in advance. By controlling the vertical movement of the partition plate based on the waveform data, a wave having a waveform similar to the predetermined waveform data is generated inside the water tank by the outflowing water. Wave-making device. A water tank in which the measurement object is arranged, a water storage unit installed inside the water tank at intervals in the longitudinal direction of the water tank with respect to the measurement object, and a water storage unit on the measurement object side of the water storage unit. A partition plate constituting the surface and a moving mechanism for moving the partition plate up and down are provided, and the water storage portion opened by the upward movement of the partition plate is allowed to flow out from the measurement target side toward the measurement target. In a wave-making device that generates waves by the water in the water storage section of the octopus
A circulation means for circulating the discharged water to the water storage unit, a control unit for controlling the vertical movement of the partition plate, and a wave height sensor for detecting the wave height between the partition plate and the measurement object. A movable weir provided on the downstream side of the outflow direction of the outflowed water from the measurement object, and a wave height sensor for detecting the water level between the measurement object and the movable weir are provided for the measurement. With water stored at a predetermined water level between the object and the movable weir, the water in the water storage unit flows out toward the measurement object and flows in between the object and the movable weir. The spilled water is passed through the movable weir and circulated to the water storage unit, and the water level between the measurement object and the movable weir can be changed by the movable weir. By controlling the vertical movement of the partition plate based on the detection data by the wave height sensor and the predetermined waveform data between the water and the measurement target, the outflowed water causes the inside of the water tank. A wave having a waveform similar to the predetermined waveform data is generated, and the water level between the measurement target and the movable weir is detected by the wave height sensor, which detects the water level between the two. Based on this detection data and predetermined predetermined water level data that is desired to be reproduced between the measurement target and the movable weir when water flows between the two due to the generated wave, the control unit A wave-making device characterized in that the water stored between the object to be measured and the movable weir is controlled to the predetermined water level by the movable weir controlled by. A movable weir is provided on the downstream side in the outflow direction of the outflowed water from the measurement object, water is stored between the measurement object and the movable weir, and the water level of this water is changed by the movable weir. The wave-making device according to claim 1 or 2, which is configured to be capable. The wave-making device according to claim 1 or 3 , which is configured to maintain a constant water level in the water storage unit. The wave-making device according to claim 1 or 3 , further comprising a water level gauge for measuring the water level of the water storage unit, and controlling the vertical movement of the partition plate based on the detection data of the water level gauge. The wave-making device according to claim 1 or 2 , further comprising a wave-dissipating body installed on the downstream side in the outflow direction of the outflowed water from the measurement object. The wave-making device according to claim 3 or 4 , further comprising a wave-dissipating body installed on the downstream side in the outflow direction of the outflowing water from the movable weir. The wave-making device according to any one of claims 1 to 8 , further comprising a rectifying body installed in a position closer to the partition plate than a position where the circulating water flows into the water storage unit. The water storage unit is arranged inside the water tank at intervals in the longitudinal direction of the water tank, and the partition plate constituting the surface of the water storage unit on the measurement object side is moved upward. In a wave-making method in which the measurement object side of the portion is opened to allow water in the water storage portion to flow out toward the measurement object, and waves are generated by the discharged water.
The water tank has a double bottom surface structure having an upper bottom surface and a lower bottom surface, and the measurement object and the water storage portion are arranged on the upper bottom surface, and water is stored between the upper bottom surface and the lower bottom surface. A portion is formed, and communication portions that penetrate vertically are provided at both ends of the upper bottom surface in the longitudinal direction, and the water that has flowed into the water storage portion through the communication portion is circulated to the water storage portion to cause the outflow. The water is circulated to the water storage unit, the wave height of the wave is detected between the partition plate and the measurement object by the wave height sensor, and the partition plate is based on the detection data and the predetermined waveform data. A wave-making method, characterized in that a wave having a waveform similar to the predetermined waveform data is generated by the outflowing water by controlling the vertical movement of the water. The water storage unit is arranged inside the water tank at intervals in the longitudinal direction of the water tank, and the partition plate constituting the surface of the water storage unit on the measurement object side is moved upward. In a wave-making method in which the measurement object side of the portion is opened to allow water in the water storage portion to flow out toward the measurement object, and waves are generated by the discharged water.
While keeping the water level of the water storage section constant by overflowing the water in the water storage section to the side facing the partition plate, the outflowed water is circulated to the water storage section, and the partition plate and the partition plate are used. By detecting the wave height of the wave with the measurement target by the wave height sensor and controlling the vertical movement of the partition plate based on the detection data and the predetermined waveform data, the outflowed water causes the water to flow out. A wave-making method characterized in that a wave having a waveform close to the predetermined waveform data is generated. The water storage unit is arranged inside the water tank at intervals in the longitudinal direction of the water tank, and the partition plate constituting the surface of the water storage unit on the measurement object side is moved upward. In a wave-making method in which the measurement object side of the portion is opened to allow water in the water storage portion to flow out toward the measurement object, and waves are generated by the discharged water.
A movable weir is provided on the downstream side in the outflow direction of the outflowed water from the measurement object, and water is stored at a predetermined water level between the measurement object and the movable weir in the water storage unit. Water flows out toward the measurement object and flows between the object and the movable weir, and the outflowed water passes through the movable weir and circulates in the water storage portion, and also the partition plate. The water that has flowed out is detected by a wave height sensor between the water and the object to be measured, and the vertical movement of the partition plate is controlled based on the detection data and the predetermined waveform data. A wave height sensor that generates a wave having a waveform similar to the predetermined waveform data and detects the water level of water stored between the measurement object and the movable dam is used between the two. The water level is detected, and this detection data is converted into predetermined predetermined water level data that is desired to be reproduced between the measurement target and the movable weir when water flows between them due to the generated wave. Based on this, a wave-making method characterized in that the water stored between the measurement object and the movable weir is controlled to the predetermined water level by changing the vertical height of the movable weir. A movable weir is provided on the downstream side in the outflow direction of the outflowed water from the measurement object, and water is stored at a predetermined water level between the measurement object and the movable weir in the water storage unit. Water flows out toward the measurement object and flows between the object and the movable weir, and the outflowed water is passed through the movable weir and circulated to the water storage unit, and the measurement is performed. The wave height sensor that detects the water level of the water stored between the object and the movable weir detects the water level between the two, and the detection data and the generated wave are used to detect the measurement object and the movable weir. The object to be measured and the movable weir by changing the vertical height of the movable weir based on predetermined predetermined water level data to be reproduced between the two when water flows in between the two. The wave-making method according to claim 10 or 11 , wherein the water stored between the two is controlled to the predetermined water level. The wave-making method according to claim 10 or 12 , wherein the water in the water storage unit is allowed to flow out toward the measurement object while maintaining the water level of the water storage unit constant. The wave-making method according to claim 10 or 12 , wherein the water level of the water storage unit is detected by a water level gauge, and the vertical movement of the partition plate is controlled based on the detection data. The wave-making method according to any one of claims 10 to 15 , wherein the water circulated in the water storage unit is supplied to the partition plate side by passing through a rectifying body provided in the water storage unit. The wave-making method according to claim 10 or 11 , wherein the wave that pushes toward the downstream side of the outflow direction of the outflowing water from the measurement object is extinguished by a wave-dissipating body. The wave-making method according to claim 12 or 13 , wherein the wave that is pushed downstream of the movable weir in the outflow direction of the outflowed water is extinguished by a wave-dissipating body.

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