JP2019119215A5 - - Google Patents

Description

Anti-vibration device using swirling flow and anti-vibration method using swirling flow

The present invention relates to an anti-sway device and an anti-sway method for reducing the vibration of a structure such as a ship or a floating body.

A fluid type anti-rolling device represented by an anti-rolling tank (ART) is used as a device for reducing the shaking of a structure such as a ship or a floating body. The anti-rolling tank can reduce the shaking of the structure by moving the liquid in the tank mounted on the structure.

Further, Patent Document 1 discloses a rotary sway damping device that includes a gyro that rotates at high speed, a gimbal that supports the gyro, and the like, and suppresses rotary sway of a ship / ship, a ski gondola, a ropeway, or the like. Has been done.
Further, Patent Document 2 includes a housing in which a flow path through which a fluid circulates is formed, an electrode portion to which a voltage is applied to generate a flow in the fluid, and the like, and a fluid rate gyro for measuring angular velocities of three axes. Is disclosed.
Further, in Patent Document 3, in a fluid gyro, a fluid whose apparent viscosity changes according to a change in an applied electric field is circulated in a hollow annular portion, and an external force exceeding an allowable amount is applied. When detected, a method of changing the restoring force by applying an electric field to the fluid is disclosed.
Further, Patent Document 4 includes a rotor exhibiting characteristics as a gyroscope at high speed rotation, two shafts connected to the rotor via gears, a braking means for braking the shafts, a ballast tank, and the like. , A gyro-type stabilizer that stabilizes the posture of the vehicle is disclosed.

Japanese Unexamined Patent Publication No. 5-272585 Japanese Unexamined Patent Publication No. 2011-149765 Japanese Unexamined Patent Publication No. 2001-33254 Special Publication No. 48-40233

However, since the fluid type anti-rolling device represented by the conventional anti-rolling tank passively acts on the shaking of the structure, it is shaken when the shaking characteristics such as the natural frequency of the structure change. There is a problem that the effect is significantly reduced. In addition, the conventional fluid type rocking device only supports one-way rolling (Roll) or pitch (Pitch), and L / B (L: length, B: width) becomes small. It is insufficient as an anti-vibration measure for such work boats and floating offshore plants.

Further, a mechanical vibration damping device using a gyro, such as the rotary vibration damping device described in Patent Document 1 and the gyro type stabilizer described in Patent Document 4, has a complicated configuration and control, and is durable. There are problems in terms of sex and cost. Moreover, due to its structure, it is difficult to apply it to large structures such as ships and floating bodies.
Further, the fluid rate gyro described in Patent Document 2 measures the angular velocities of three axes, and does not relate to an anti-vibration device.
Further, the fluid gyro described in Patent Document 3 is attached with a plurality of electrode plates and a container for enclosing a special fluid, and the restoring force is changed by applying a voltage, which complicates the configuration. ..

Therefore, the present invention makes it possible to actively control the vibration damping effect that reduces the vibration of structures such as ships and floating bodies, and also enables vibration in a wide frequency range regardless of the natural frequency of the structure. An object of the present invention is to provide a vibration damping device using a swirling flow and a vibration damping method using a swirling flow.

In the anti-vibration device using a swirling flow according to claim 1, the plan-viewed shape is annular in that the liquid is mounted on the structure and is stored with a space having a height above the liquid. A liquid storage means, a swirling flow generating means for generating a swirling flow in the liquid, and a swirling flow controlling means for controlling the swirling flow generating means are provided, and the swing of the structure can be reduced by controlling the swirling flow. It is a feature.
According to the first aspect of the present invention, the damping effect can be actively controlled by utilizing the fluid force generated from the centrifugal force of the swirling flow or the like. Further, by controlling the swirling flow, it is possible to oscillate in a wide frequency range without depending on the natural frequency of the structure.

The present invention according to claim 2 is characterized in that the swirling flow control means controls the speed of the swirling flow.
According to the second aspect of the present invention, the damping effect can be adjusted by controlling the speed of the swirling flow.

The present invention according to claim 3 is provided with a liquid supply / recovery means for supplying and recovering a liquid, and the height of the space is increased by increasing or decreasing the amount of the liquid stored in the liquid storage means by the liquid supply / recovery means. It is characterized by adjusting.
According to the third aspect of the present invention, the anti-sway effect can be easily adjusted by increasing or decreasing the amount of the liquid.

The present invention according to claim 4 is characterized in that the swirling flow generating means also serves as a liquid supply / recovery means.
According to the fourth aspect of the present invention, since the liquid supply / recovery means can be configured with fewer devices, the installation location, cost, and the like can be reduced.

The present invention according to claim 5 is characterized in that the liquid storage means includes a top plate and an elevating means for raising and lowering the top plate, and the height of the space is adjusted by raising and lowering the top plate by the elevating means.
According to the fifth aspect of the present invention, when the liquid level or the flow velocity of the swirling flow is changed, it becomes easy to correct the height of the space to the optimum height. In addition, the anti-vibration effect can be adjusted by changing the size of the liquid in contact with the top plate.

According to the sixth aspect of the present invention, when the height of the space is hc and the height from the bottom surface of the liquid storage means to the liquid surface of the liquid is ww, (hc + hw) / hp exceeds 1. It is characterized in that it is set to 6 or less.
According to the sixth aspect of the present invention, the swirling flow can be easily brought into contact with the upper surface or the top plate of the liquid storage means, and a higher damping effect can be obtained.

The present invention according to claim 7 is characterized in that the swing detecting means for detecting the swing of the structure is provided, and the swirling flow is controlled according to the magnitude of the swing of the structure detected by the swing detecting means. To do.
According to the seventh aspect of the present invention, the damping effect can be adjusted more appropriately according to the magnitude of the swing of the structure.

The present invention according to claim 8 is characterized in that the swirl flow control means controls the swirl flow so that the size of the swirl flow in contact with the upper surface of the liquid storage means or the top plate is within a predetermined range.
According to the eighth aspect of the present invention, a higher damping effect can be obtained.

The present invention according to claim 9 is characterized in that the outer portion of the bottom portion of the liquid storage means forms a curved surface.
According to the ninth aspect of the present invention, it is possible to increase the liquid level or the amount of uplift of the liquid when a swirling flow is generated.

The present invention according to claim 10 is characterized in that the structure is a ship or a floating body floating on water.
According to the tenth aspect of the present invention, it is possible to reduce the swing of a ship or a floating body by utilizing the fluid force generated from the centrifugal force of the swirling flow or the like. In addition, it is possible to oscillate in a wide frequency range in response to waves and the like without depending on the natural frequency of the ship or floating body.

In the vibration damping method using a swirling flow according to claim 11, a space having a height above the liquid is provided in the liquid storage means having an annular shape mounted on the structure in a plan view. It is characterized in that the swing of the structure is reduced by storing the liquid while leaving it, generating a swirling flow in the liquid, and controlling the swirling flow.
According to the eleventh aspect of the present invention, the damping effect can be actively controlled by utilizing the fluid force generated from the centrifugal force of the swirling flow or the like. Further, by controlling the swirling flow, it is possible to oscillate in a wide frequency range without depending on the natural frequency of the structure.

The invention according to claim 12 is characterized in that the velocity of the swirling flow is controlled.
According to the twelfth aspect of the present invention, the damping effect can be adjusted by controlling the speed of the swirling flow.

The present invention according to claim 13 is characterized in that the height of the space is adjusted by increasing or decreasing the amount of the liquid stored in the liquid storage means.
According to the thirteenth aspect of the present invention, the anti-sway effect can be easily adjusted by increasing or decreasing the amount of the liquid.

The present invention according to claim 14 is characterized in that the height of the space is adjusted by raising and lowering the top plate provided in the liquid storage means.
According to the thirteenth aspect of the present invention, when the liquid level or the flow velocity of the swirling flow is changed, it becomes easy to correct the height of the space to the optimum height. In addition, the anti-vibration effect can be adjusted by changing the size of the liquid in contact with the top plate.

According to the fifteenth aspect of the present invention, when the height of the space is hc and the height from the bottom surface of the liquid storage means to the liquid surface of the liquid is ww, (hc + hw) / hp exceeds 1. It is characterized in that it is set to 6 or less.
According to the fifteenth aspect of the present invention, the swirling flow can be easily brought into contact with the upper surface or the top plate of the liquid storage means, and a higher damping effect can be obtained.

The present invention according to claim 16 is characterized in that the swirling flow is controlled so that the dimension in which the swirling flow comes into contact with the upper surface or the top plate of the liquid storage means is within a predetermined range.
According to the 16th aspect of the present invention, a higher damping effect can be obtained.

According to the anti-vibration device using the swirling flow of the present invention, the anti-vibration effect can be actively controlled by utilizing the fluid force generated from the centrifugal force of the swirling flow. Further, by controlling the swirling flow, it is possible to oscillate in a wide frequency range without depending on the natural frequency of the structure.

Further, when the swirling flow control means controls the speed of the swirling flow, the damping effect can be adjusted by controlling the speed of the swirling flow.

In addition, when a liquid supply / recovery means for supplying and recovering liquid is provided and the height of the space is adjusted by increasing or decreasing the amount of liquid stored in the liquid storage means by the liquid supply / recovery means, The anti-sway effect can be easily adjusted by increasing or decreasing the amount of liquid.

Further, when the swirling flow generating means also serves as the liquid supply / recovery means, the liquid supply / recovery means can be configured with a smaller number of devices, so that the installation location and cost can be reduced.

Further, when the liquid storage means is provided with a top plate and an elevating means for raising and lowering the top plate, and the height of the space is adjusted by raising and lowering the top plate by the elevating means, the liquid level or the flow velocity of the swirling flow is changed. In addition, it becomes easier to correct the height of the space to the optimum height. In addition, the anti-vibration effect can be adjusted by changing the size of the liquid in contact with the top plate.

Further, when the height of the space is hc and the height from the bottom surface of the liquid storage means to the liquid surface of the liquid is hw, (hc + hw) / hp is set to more than 1 and 1.6 or less. Makes it easier for the swirling flow to come into contact with the upper surface or the top plate of the liquid storage means, and a higher damping effect can be obtained.

Further, when a swing detecting means for detecting the swing of the structure is provided and the swirling flow is controlled according to the magnitude of the swing of the structure detected by the swing detecting means, the magnitude of the swing of the structure is controlled. The damping effect can be adjusted more appropriately according to the above.

Further, when the swirling flow control means controls the swirling flow so that the size of the swirling flow comes into contact with the upper surface of the liquid storage means or the top plate within a predetermined range, a higher damping effect can be obtained. it can.

Further, when the outer portion of the bottom portion of the liquid storage means has a curved surface, the liquid level or the amount of uplift of the liquid when a swirling flow is generated can be increased.

Further, when the structure is a ship or a floating body floating on water, the swing of the ship or the floating body can be reduced by utilizing the fluid force generated from the centrifugal force of the swirling flow or the like. In addition, it is possible to oscillate in a wide frequency range in response to waves and the like without depending on the natural frequency of the ship or floating body.

According to the anti-vibration method using the swirling flow of the present invention, the anti-vibration effect can be actively controlled by utilizing the fluid force generated from the centrifugal force of the swirling flow. Further, by controlling the swirling flow, it is possible to oscillate in a wide frequency range without depending on the natural frequency of the structure.

Further, when controlling the speed of the swirling flow, the damping effect can be adjusted by controlling the speed of the swirling flow.

Further, when the height of the space is adjusted by increasing or decreasing the amount of the liquid stored in the liquid storage means, the anti-sway effect can be easily adjusted by increasing or decreasing the amount of the liquid.

In addition, when adjusting the height of the space by raising and lowering the top plate provided for the liquid storage means, it is easy to correct the height of the space to the optimum height when the liquid level or the flow velocity of the swirling flow is changed. Become. In addition, the anti-vibration effect can be adjusted by changing the size of the liquid in contact with the top plate.

Further, when the height of the space is hc and the height from the bottom surface of the liquid storage means to the liquid surface of the liquid is hw, (hc + hw) / hp is set to more than 1 and 1.6 or less. Makes it easier for the swirling flow to come into contact with the upper surface or the top plate of the liquid storage means, and a higher damping effect can be obtained.

Further, when the swirling flow is controlled so that the dimension in which the swirling flow comes into contact with the upper surface of the liquid storage means or the top plate is within a predetermined range, a higher damping effect can be obtained.

The figure which shows the state which mounted the anti-vibration device by one Embodiment of this invention on a structure. The figure which shows the structure of the abduction device Explanatory drawing of the damping effect by the same damping device The figure which shows the structure of the oscillating device by another embodiment of this invention Central sectional view of the liquid storage means in the anti-rolling device according to still another embodiment of the present invention. Diagram showing an example of mounting on a structure Diagram showing an example of mounting on a structure External view of the model used for verification Central sectional view of the liquid storage means used for verification Relationship between flow velocity and damping ratio Relationship between flow velocity and damping ratio Central sectional view of the liquid storage means used for verification

Hereinafter, a vibration damping device using a swirling flow and a rocking method using a swirling flow according to the embodiment of the present invention will be described.

FIG. 1 is a view showing a state in which the anti-vibration device according to the present embodiment is mounted on a structure, in which the upper part is a top view and the lower part is a side view.
In FIG. 1, the structure 2 is a ship. One anti-sway device 1 is mounted on the forecastle deck and one on the stern deck of the ship (structure 2).
The anti-sway device 1 includes a tank (liquid storage means 10) having an elliptical annular shape in a plan view. The liquid storage means 10 is installed with the long axis direction as the ship width direction in order to suppress rolling of the structure 2 due to wave wind or the like. A liquid 20 such as water is stored in the liquid storage means 10. The liquid storage means 10 can also be configured by using a hose or a tube instead of the tank.

2A and 2B are views showing the configuration of the anti-vibration device according to the present embodiment, FIG. 2A is a front view, FIG. 2B is a top view, FIG. 2C is a side view, and FIG. 2D. ) Is a sectional view taken along the line AA of FIG. 2B when the circulation pump is stopped, and FIG. 2E is a sectional view taken along the line AA of FIG. 2B when the circulation pump is operated.
In addition to the liquid storage means 10, the anti-sway device 1 supplies and recovers the swirling flow generating means 30 that generates a swirling flow in the liquid 20, the swirling flow controlling means 40 that controls the swirling flow generating means 30, and the liquid 20. The liquid supply / recovery means 50 to be performed and the swing detection means 60 for detecting the swing of the structure 2 are provided.

As shown in FIG. 2B, the liquid storage means 10 is formed in an elliptical annular shape including a curved pipe portion 10A and a straight pipe portion 10B. Further, as shown in FIG. 2A, the outer portion of the bottom portion of the liquid storage means 10 has a curved surface.
As shown in FIG. 2D, the liquid level of the liquid 20 stored in the liquid storage means 10 is a state in which the liquid storage means 10 is in a horizontal state and no swirling flow is generated in the liquid 20. Is adjusted so that the space X remains above the liquid level.
The space X is a space generated above the liquid level, and there is no space that substantially hinders the rise of the liquid level. Therefore, in the liquid storage means 10 shown in FIG. 2, the space X is from the liquid surface to the upper surface 11 inside the liquid storage means 10.

The swirling flow generating means 30 includes a circulation pump 31, a suction pipe 32, and an injection pipe 33.
The circulation pump 31 is arranged in an elliptical hole 10C surrounded by the liquid storage means 10. The rear end of the suction pipe 32 is connected to the suction port of the circulation pump 31, and the rear end of the injection pipe 33 is connected to the discharge port of the circulation pump 31.
The suction pipe 32 includes a first suction pipe 32A and a second suction pipe 32B. The tip of the first suction pipe 32A is connected to the outer peripheral side of one straight pipe portion 10B. The tip of the second suction pipe 32B is connected to the outer peripheral side of the other straight pipe portion 10B.
The injection pipe 33 includes a first injection pipe 33A and a second injection pipe 33B. The tip of the first injection pipe 33A is connected to the inner peripheral side of one straight pipe portion 10B. The tip of the second injection pipe 33B is connected to the inner peripheral side of the other straight pipe portion 10B. Further, the tips of the first injection pipe 33A and the second injection pipe 33B are configured to eject the liquid 20 delivered from the circulation pump 31 along the flow direction of the swirling flow generated in the liquid storage means 10. ing.
The swirling flow generating means 30 configured in this way can generate a swirling flow in the liquid storing means 10 by circulating the liquid 20 in the liquid storing means 10 by the circulation pump 31.
When a liquid that flows by applying a voltage is stored in the liquid storage means, the electrode to which the voltage is applied is also a component of the swirling flow generating means.

The swirl flow control means 40 controls the swirl flow by controlling the swirl flow generation means 30. For example, the swirling flow can be generated by starting the operation of the circulation pump 31, and the swirling flow can be eliminated by stopping the operation of the circulation pump 31.
FIG. 2B shows a state in which the circulation pump 31 is in operation. When the operation of the circulation pump 31 is started, the liquid 20 stored in the liquid storage means 10 is sucked into the circulation pump 31 via the suction pipe 32 and discharged to the liquid storage means 10 via the injection pipe 33. To.
As described above, since the liquid 20 discharged from the injection pipe 33 is ejected along the flow direction of the swirling flow, the liquid 20 contained in the liquid storage means 10 flows, and eventually becomes a swirling flow. In FIG. 2B, the solid line arrow indicates the flow direction of the circulating liquid 20, and the dotted line arrow indicates the flow direction of the swirling flow of the liquid 20 in the liquid storage means 10.

When a swirling flow is generated, a centrifugal force is generated when the flow direction of the swirling flow of the liquid 20 in the liquid storage means 10 changes, and as shown in FIG. 2 (e), the liquid 20 stored in the liquid storage means 10 The liquid level on the outer peripheral side rises and the liquid level on the inner peripheral side falls, resulting in a height difference. The fluid force generated from this centrifugal force (inertial force) or the like can be actively controlled so as to reduce the swing of the structure 2. Further, by controlling the swirling flow, it is possible to oscillate in a wide frequency range without depending on the natural frequency of the structure 2.
Further, in the present embodiment, since the outer portion of the bottom portion of the liquid storage means 10 has a curved surface, it is possible to increase the liquid level or the amount of uplift of the liquid 20 when a swirling flow is generated.
If the tip of the suction pipe 32 is connected to the inner peripheral side of the liquid storage means 10, when a swirling flow is generated, the liquid level on the inner peripheral side of the liquid 20 drops, so that the suction pipe 32 The tip may be exposed and the circulation pump 31 may cause suction failure. Therefore, it is preferable that the tip of the suction pipe 32 is connected to the outer peripheral side where the liquid level of the liquid 20 rises when a swirling flow is generated.
Further, as shown in FIG. 2B, when the tip of the suction pipe 32 is connected to the upstream side of the straight pipe portion 10B and the tip of the injection pipe 33 is connected to the upstream side of the curved pipe portion 10A, It becomes easier to generate a swirling flow.

Further, the swirl flow control means 40 can control the speed of the swirl flow by adjusting the opening ratio of the suction port of the circulation pump 31 to increase or decrease the amount of the liquid 20 injected into the liquid storage means 10. By controlling the speed of the swirling flow, the damping effect of the damping device 1 can be adjusted.
Further, the swirling flow control means 40 controls the swirling flow according to the magnitude of the swing of the structure 2 detected by the swing detecting means 60 such as a sensor. As a result, the damping effect of the rocking device 1 can be adjusted more appropriately according to the magnitude of the swing of the structure 2. The rocking detecting means 60 may be provided directly on the structure 2 or on the rocking device 1, and may be installed anywhere as long as the rocking of the structure 2 can be detected.

The liquid supply / recovery means 50 includes a reversible pump (not shown) that transfers the liquid 20. Further, a storage tank (not shown) for storing the liquid 20 may be further provided.
The liquid supply / recovery means 50 can increase the amount (liquid level) of the liquid 20 stored in the liquid storage means 10 by supplying the liquid 20 to the liquid storage means 10. Further, the amount of the liquid 20 stored in the liquid storage means 10 can be reduced by collecting the liquid 20 stored in the liquid storage means 10. By increasing or decreasing the amount of the liquid 20 stored in the liquid storage means 10 in this way, the height hc of the space X can be adjusted. As a result, the damping effect of the damping device 1 can be easily adjusted.
In the liquid storage means 10 shown in FIG. 2, the height from the liquid surface of the liquid 20 to the upper surface 11 is the height hc of the space X. When the liquid level of the liquid 20 (height from the bottom surface 12 of the liquid storage means 10 to the liquid level) is hw, by setting (hc + hw) / hp to more than 1 and 1.6 or less, the swirling flow is raised to the upper surface. It becomes easy to come into contact with 11, and a higher damping effect can be obtained.
Further, when the liquid storage means 10 is in a horizontal state, a higher vibration damping effect can be obtained by controlling the swirling flow so that the dimension in which the swirling flow contacts the upper surface 11 is within a predetermined range.
Further, the liquid supply / recovery means 50 may also serve as the swirling flow generating means 30. For example, if the liquid 20 is supplied or recovered via the circulation pump 31, the reversible pump or the like can be omitted, so that the installation location and cost can be reduced.

FIG. 3 is an explanatory diagram of the damping effect.
In FIG. 3, the liquid storage means 10 of the anti-sway device 1 is fixed to the structure 2 via the support base 3.
FIG. 3A shows a state in which the structure 2 is horizontal. When the structure 2 is horizontal, the liquid storage means 10 is also horizontal. When a high-speed swirling flow is generated in the liquid storage means 10, the liquid 20 is pushed out in the radial direction by the centrifugal force of the swirling flow, so that the liquid level of the liquid 20 on the outer peripheral side rises and the liquid 20 on the inner peripheral side rises. The liquid level drops. The dotted arrow in FIG. 3 indicates the rotation direction of the swirling flow.
FIG. 3B shows a state in which the structure 2 is tilted due to a swing caused by a wave wind or the like. When the structure 2 is tilted, the liquid storage means 10 is also tilted, the liquid 20 in the liquid storage means 10 is biased toward the lower side, and the amount of the lower liquid 20 is increased. Then, when the liquid 20 is pushed out in the radial direction by the centrifugal force of the swirling flow, the fluid force acting to push back the upper surface 11 and the bottom surface 12 of the inclined liquid storage means 10 is generated more on the lower side, which reduces the amount. A shaking effect can be obtained. In FIG. 3B, the direction and magnitude of the force acting as the damping effect are indicated by solid arrows.
As shown in FIG. 2 or 3, the anti-vibration device 1 in which the height of the flow path in the liquid storage means 10 is fixed can be easily applied to a relatively large structure 2. When applied to the structure 2, the appearance shape and flow path shape of the liquid storage means 10, the liquid level of the liquid 20, the output of the circulation pump 31, and the like are designed in advance.

For the adjustment of the vibration damping effect by the rocking device 1, for example, when the swing of the structure 2 is small, the liquid 20 is put into the liquid storage means 10 until it is almost full (hc≈0) to generate a swirling flow. Or, control so as to generate a low-speed swirling flow, and when the fluctuation of the structure 2 is large, adjust the liquid level hw so that (hc + hw) / hw exceeds 1 and becomes 1.6 or less. It is performed by controlling so as to generate a high-speed swirling flow.

The liquid storage means has an annular shape with a plan view of an elliptical shape as shown in FIG. 2 or FIG. 3, an annular shape with a plan view of a perfect circle, and a shape with a rounded corner in a plan view. You can select an annular shape such as an annular shape in which the direction of the liquid passage changes gently.
FIG. 4 is a diagram showing a configuration of an anti-vibration device according to another embodiment of the present invention, and includes an annular liquid storage means having a perfectly circular shape in a plan view. The same functional members as those in the above-described embodiment are designated by the corresponding reference numerals, and the description thereof will be omitted.
The tips of the three injection tubes 133 are connected to the inner peripheral side of the liquid storage means 110 formed in a perfect circular ring shape at equal intervals, and the tips of the two suction tubes 132 are connected to the outer peripheral side at equal intervals. The tips of the are connected 180 degrees apart. In FIG. 4, the solid line arrow indicates the flow direction of the circulating liquid 200, and the dotted line arrow indicates the flow direction of the swirling flow of the liquid 120 in the liquid storage means 110.

Further, the liquid storage means may have a structure in which the height of the flow path is variable, instead of the structure in which the height of the flow path is fixed as shown in FIG. 2 or FIG.
FIG. 5 is a central sectional view of a liquid storage means in the anti-rolling device according to still another embodiment of the present invention. The same functional members as those in the above-described embodiment are designated by the corresponding reference numerals, and the description thereof will be omitted. Further, in FIG. 5, the dotted line arrow indicates the flow direction of the swirling flow generated in the liquid 220 stored in the liquid storage means 210.
Inside the liquid storage means 210, a top plate 270 is provided above the liquid level of the stored liquid 220. Since the top plate 270 is configured to be movable and fixed in the liquid storage means 210 up and down by the elevating means 280, the height of the space X can be increased even when the liquid level of the liquid 20 and the flow velocity of the swirling flow are changed. It becomes easy to adjust to the optimum height. Further, the dimension (width) at which the liquid 20 comes into contact with the top plate 270 can be adjusted. As described above, the anti-vibration device 201 in which the height of the flow path in the liquid storage means 210 is variable is relatively small because it is easier to adjust the anti-vibration effect than the anti-sway device in which the height of the flow path is fixed. It is easy to apply to the structure of.
The elevating means 280 is configured by any means such as a rack & pinion type, a winding type, and a hydraulic type.
The liquid level of the liquid 220 stored in the liquid storage means 210 is a space X above the liquid level when the liquid storage means 210 is in a horizontal state and no swirling flow is generated in the liquid 220. Is adjusted so that remains. As described above, the space X is a space generated above the liquid level and in which there is no space that substantially hinders the rise of the liquid level. Therefore, in the liquid storage means 210 shown in FIG. 5, the space X is not from the liquid surface to the upper surface 211 of the liquid storage means 210, but from the liquid surface to the top plate 270.

A predetermined gap C is provided between the outer surface 271 of the top plate 270 and the outer peripheral inner surface 213 of the liquid storage means 210. Further, a predetermined gap D is provided between the inner side surface 272 of the top plate 270 and the inner peripheral inner surface 214 of the liquid storage means 210.
If there is no gap between the side surface of the top plate 270 and the inner surface of the liquid storage means 210, if the distance from the liquid surface to the top plate 270 is small, the liquid 220 on the outer peripheral side will rise when a swirling flow is generated. Is blocked by the top plate 270, so that a sufficient height difference does not occur between the outer peripheral side and the inner peripheral side.
However, if C and D are provided in the gap between the side surface of the top plate 270 and the inner surface of the liquid storage means 210 as in the present embodiment, even if the distance from the liquid surface to the top plate 270 is small, Since the liquid 2 can ride on the upper surface of the top plate 270 through the gap C, a sufficient height difference can be provided between the outer peripheral side and the inner peripheral side of the liquid 220. Since the liquid 220 that has run on the upper surface of the top plate 270 flows down from the top plate 270 through the gap D, it can be returned to the swirling flow.
Here, since the contact area between the lower surface of the top plate 270 and the liquid 20 can be increased by making the gap C as narrow as possible, if the width of the flow path of the liquid storage means 210 is B, the width of the gap C is It is preferably 0.1B or less, and more preferably 0.03B or less.
On the other hand, since the gap D plays a role of returning the liquid 220 that has run on the upper surface of the top plate 270 below the top plate 270, the gap D is made wider than the gap C. The width of the gap D is preferably 0.4B or less, and more preferably 0.2B or less.
When a hose or tube is used instead of the tank as the liquid storage means 10, the hose or tube is pressed by an external force to deform the shape of the space, and the dimension of contact with the height of the space or the upper surface. It is also possible to change. In this case, the amount of the liquid 20 may be changed as needed.

The anti-sway device described with reference to FIGS. 1 to 5 can be mounted not only on a ship but also on a structure such as a floating body floating on water. 6 and 7 show examples of mounting on other structures. In each of FIGS. 6 (a) to 6 (c) and 7 (a) and 7 (b), the upper row is a top view and the lower row is a side view.
In FIG. 6A, the structure is a work vessel 302, and an anti-vibration device 301 including a liquid storage means 310 having a circular ring shape in a plan view inside the hull of the work vessel 302 is mounted. It is a figure which shows the example. By arranging the liquid storage means 310 in the direction of the captain and the direction of the width of the ship, it is possible to obtain the anti-sway effect at the same time against the two directions of rolling and pitching. Further, the liquid storage means 310 also serves as a ballast tank, and seawater can be used as the liquid 320 to be stored. If there is a mounting space on the deck of the work boat 302, an elliptical or oval annular anti-sway device may be mounted.
FIG. 6B shows a ship 402 whose structure is called a barge or barge, and includes a liquid storage means 410 having a circular shape with a rounded quadrangle in a plan view inside the hull of the ship 402. It is a figure which shows the example which mounted the apparatus 401. By arranging the liquid storage means 410 in the direction of the captain and the direction of the width of the ship, it is possible to obtain the anti-sway effect at the same time with respect to the two directions of rolling and pitching. Further, the liquid storage means 410 also serves as a ballast tank, and seawater can be used as the liquid 420 to be stored. If there is a mounting space on the deck of the ship 402, an elliptical or oval ring-shaped anti-vibration device may be mounted.
FIG. 6 (c) shows a ship 502 whose structure is called a barge or barge, and a liquid storage means 510 having an elliptical annular shape on the forecastle and poop decks of the ship 502. It is a figure which shows the example which mounted the anti-vibration device 501 provided. By installing the liquid storage means 510 in the long axis direction as the ship width direction, it is possible to obtain an anti-rolling effect against rolling.
FIG. 7A shows a liquid storage means 610 in which the structure is a floating body 602 called a semi-submersible (semi-sub), and the shape of the floating body 602 is formed into a perfect circular ring in a plan view inside and under the deck. It is a figure which shows the example which mounted the anti-vibration device 601 provided. By arranging the liquid storage means 610 along the length direction and the width direction of the floating body, it is possible to obtain the anti-sway effect at the same time with respect to the two-direction shaking of rolling and pitching.
FIG. 7B shows an offshore power generation device 702 in which the structure is equipped with a wind turbine, and the shape seen in a plan view is a perfect circle on the upper part of a floating body provided below the support supporting the blade of the offshore power generation device 702. It is a figure which shows the example which mounted the anti-vibration device 701 including the liquid storage means 710 formed in an annular shape. The left figure of FIG. 7B is a semi-sub type, and the right figure is a spar type.
Although not shown, the anti-sway device according to the present invention can also be applied when the structure is a gondola, a lift, or the like used in a ski resort or the like.

Next, the verification result of the anti-sway effect by the anti-sway device will be described.
FIG. 8 is an external view of the model used for verification.
FIG. 8A is a perspective view of an anti-sway device 801 including a liquid storage means 810 that imitates an annular tank. However, the upper part of the liquid storage means 810 is open. The suction pipe 832 and the injection pipe 833 are each one. The tip of the suction pipe 832 is connected to the bottom surface of the liquid storage means 810, and the injection pipe 833 is raised from the bottom surface of the liquid storage means 810 at a position 180 degrees away from the bottom surface. An elbow pipe joint is attached to the tip of the injection pipe 833, and the injection port is directed in the same direction as the swirling flow. A circulation pump 831 is provided in the central portion of the liquid storage means 810.
As shown in FIG. 8B, the anti-vibration device 801 is mounted on the vibration generating means 802 corresponding to the structure.
FIG. 8C is a perspective view showing a state in which the liquid 820 is stored in the liquid storage means 810. Above the liquid 820, a top plate 870 formed in a disk shape according to the shape of the flow path is arranged.

FIG. 9 is a central sectional view of the liquid storage means used for verification.
The cross section of the liquid storage means 810 is rectangular, and the top plate 870 arranged above the liquid level of the liquid 820 and below the upper surface 811 of the liquid storage means 810 is provided by an elevating means (not shown). It can be raised and lowered. The height hc of the space X can be adjusted by raising or lowering the top plate 870. The height hc of the space X is the height from the liquid surface of the liquid 820 to the top plate 870.
In the verification, the liquid level and the flow velocity of the liquid 820 stored in the liquid storage means 810, and the change in the damping ratio due to the difference in the cross-sectional shape of the flow path were measured. The liquid 820 was tap water.

In the verification, the opening ratio of the suction port of the circulation pump 831 was set to 100% (# 0), 45% (# 1), and 30% (# 2) to change the flow velocity of the swirling flow generated in the liquid 820. , The attenuation ratio at each set liquid level (hw = 50 mm, 75 mm, 100 mm, 125 mm) was measured. The larger the opening ratio of the suction port of the circulation pump 831, the faster the flow velocity of the swirling flow.
At the time of measurement, the upper surface 811 and the top plate 870 of the liquid storage means 810 were not installed, and the upper part above the liquid 820 was opened. FIG. 10 is a diagram showing the relationship between the flow velocity and the damping ratio based on the measurement results. In FIG. 10, “Δ” indicates the result of liquid level hw = 50 mm, “◯” in FIG. 10 indicates the result of liquid level hw = 75 mm, and “□” in FIG. 10 indicates the result of liquid level hw = 100 mm. , “X” in FIG. 10 indicates the result of the liquid level hw = 125 mm. The vertical axis is the damping ratio ζ, and the horizontal axis is the flow velocity (cm / s).
It can be seen that the damping ratio ζ tends to increase as the flow velocity of the swirling flow increases at any liquid level hw.
Therefore, the anti-vibration device of the present invention can obtain a larger anti-vibration effect by increasing the flow velocity of the swirling flow generated in the liquid storage means.

Next, the ratio hl / hp of the height hl from the bottom surface 812 to the top plate 870 to the liquid level hh is sequentially changed between 1.0 and more and 1.5 or less for the liquid level hw = 75 mm and 100 mm. The damping ratio when the flow velocity of the swirling flow was adjusted by changing the opening ratio of the suction port of the circulation pump 831 to 100% (# 0), 45% (# 1), and 30% (# 2) was measured.
FIG. 11 is a relationship diagram between the flow velocity and the damping ratio based on the measurement results. In FIG. 11, the vertical axis is the damping ratio ζ, and the horizontal axis is the ratio hl / hp of the height hl and the liquid level hl.
Further, FIG. 12 is a central sectional view of the liquid storage means used for verification, FIG. 12A shows a state in which a swirling flow is not generated, and FIG. 12B shows a state in which a swirling flow is generated. There is.

FIG. 11A shows the result when the liquid level hw = 75 mm, “●” shows the result when the opening ratio is 100% (# 0), and “○ with light ink” shows the result when the opening ratio is 45% (○). The result in the case of # 1) is shown, the "○ with a diagonal line" shows the result when the opening ratio is 30% (# 2), and the "○" shows the result when there is no flow in the liquid 820. Shown.
FIG. 11B shows the result when the liquid level hw = 100 mm, “■” shows the result when the aperture ratio is 100% (# 0), and “□ with light ink” shows the aperture ratio of 45% (the aperture ratio is 45% (# 0). The result in case of # 1) is shown, "□ with diagonal line" shows the result when the aperture ratio is 30% (# 2), and "□" shows the result when there is no flow in the liquid 820. Shown.
From FIG. 11, it can be seen that even when the top plate 870 is provided above the liquid 820, the damping ratio ζ tends to increase as the flow velocity of the swirling flow increases. The damping ratio ζ is high when the ratio hl / hp of the height hl from the bottom surface 812 to the top plate 870 and the liquid level hl is more than 1.0 and 1.1 or less, and hl / hp is 1.2 or more. There was a tendency to decrease when it became. From this, it can be seen that when the distance between the top plate 870 and the liquid surface is large, it is difficult for the liquid 820 and the top plate 870 to come into contact with each other even if a swirling flow is generated, and the damping effect is diminished. Therefore, (hc + hw) / hw is preferably set to more than 1.0 and 1.6 or less, and more preferably more than 1.0 and less than 1.2, where the damping effect can be obtained, and 1.0. It is most preferable to set it to more than 1.1 or less.
In this way, when the flow velocity of the swirling flow is high, a good damping effect can be obtained by setting the height hc = hl-hw of the space X small, but the value of the height hc of the space X is The anti-vibration effect can be further enhanced by setting the dimension (width b) at which the liquid level raised by the swirling flow comes into contact with the top plate 870 of the liquid storage means 810 in a horizontal state within a predetermined range. The predetermined range of the width b is preferably 1/8 B or more and 1 / 2B or less with respect to the width B of the flow path of the liquid storage means 810.

If the amount of liquid 820 contained in the liquid storage means 810 is small and the swirling flow is fast, the flow may be disturbed and a clean swirling flow may not be obtained. When the flow is disturbed, self-excited vibration occurs, and the damped vibration does not converge or is amplified. In such a case, the distance between the top plate 870 and the liquid level (height hc of the space X) is set small, and the swirling flow always comes into contact with the top plate 870 even when the liquid storage means 810 is in a horizontal state. In this state, the rectifying effect works and self-excited vibration can be suppressed.

INDUSTRIAL APPLICABILITY The present invention can effectively reduce the swing generated in a structure such as a gondola or a lift, including a ship, a floating body, or an offshore wind power generator, and can contribute to safe navigation or improvement of an operating rate of the structure.

1 Anti-vibration device 2 Structure 10 Liquid storage means 11 Top surface 12 Bottom surface 20 Liquid 30 Swirling flow generating means 40 Swirling flow control means 50 Liquid supply / recovery means 60 Swing detection means 270 Top plate 280 Lifting means X Space

Claims (16)

A liquid storage means having an annular shape in a plan view for storing a liquid mounted on a structure leaving a space having a height above the liquid, and a swirling flow generating means for generating a swirling flow in the liquid. An anti-sway device using a swirl flow, which comprises a swirl flow control means for controlling the swirl flow generating means and reduces the swing of the structure by controlling the swirl flow. The anti-sway device using the swirl flow according to claim 1, wherein the swirl flow control means controls the speed of the swirl flow. Comprising a liquid supply and recovery means for performing recovery and supply of the liquid, adjusting the height of the space by increasing or decreasing the amount of the liquid accommodated in said liquid containing means in said liquid supply and recovery means The anti-vibration device using the swirling flow according to claim 1 or 2, characterized in that. The anti-sway device using the swirl flow according to claim 3, wherein the swirl flow generating means also serves as the liquid supply / recovery means. The top plate to said liquid containing means comprises a lifting means for lifting the top plate, claim from claim 1, characterized in that adjusting the height of the space by the lifting of the top plate by the lifting means A vibration damping device using the swirling flow according to any one of 4. Hc the height of the space, the height from the bottom to the liquid surface of the liquid when the hw of said liquid containing means is set below 1.6 exceed 1 (hc + hw) / hw The anti-sway device using the swirling flow according to any one of claims 1 to 5, characterized in that. The first aspect of the present invention, wherein the swing detecting means for detecting the swing of the structure is provided, and the swirling flow is controlled according to the magnitude of the swing of the structure detected by the swing detecting means. An anti-sway device using the swirling flow according to any one of claims 6. The first aspect of the present invention, wherein the swirling flow controlling means controls the swirling flow so that the swirling flow has a dimension in contact with the upper surface of the liquid storage means or the top plate within a predetermined range. Item 7. An anti-sway device using the swirling flow according to any one of items 7. The anti-sway device using a swirling flow according to any one of claims 1 to 8, wherein the outer portion of the bottom of the liquid storage means has a curved surface. The rocking device using a swirling flow according to any one of claims 1 to 9, wherein the structure is a ship or a floating body floating on water. The liquid is stored in the liquid storage means having an annular shape mounted on the structure in a plan view, leaving a space having a height above the liquid, and a swirling flow is generated in the liquid to generate the swirling flow. A vibration damping method using a swirling flow, which is characterized by reducing the swing of the structure by controlling the above. The anti-sway method using a swirling flow according to claim 11, wherein the speed of the swirling flow is controlled. The anti-sway method using a swirling flow according to claim 11 or 12, wherein the height of the space is adjusted by increasing or decreasing the amount of the liquid stored in the liquid storage means. .. The anti-vibration method using the swirling flow according to any one of claims 11 to 13, wherein the height of the space is adjusted by raising and lowering the top plate provided in the liquid storage means. Hc the height of the space, the height from the bottom to the liquid surface of the liquid when the hw of said liquid containing means is set below 1.6 exceed 1 (hc + hw) / hw The anti-vibration method using the swirling flow according to any one of claims 11 to 14, characterized in that. Any one of claims 11 to 15, wherein the swirling flow is controlled so that the dimension in which the swirling flow comes into contact with the upper surface of the liquid storage means or the top plate is within a predetermined range. Anti-vibration method using the swirling flow described in.