JP2012224291A - Rocking control device of floating body - Google Patents

Abstract

PROBLEM TO BE SOLVED: To control rocking in the yaw direction of a spar type floating body.SOLUTION: A tunnel-shaped flow passage 11 penetrating in the horizontal direction is provided on an outer peripheral part of a buoyant body 2 of a spar type floating body 1, and its one-end side opening forms a first water jetting port 6 for jetting a water flow in a direction for imparting a turning force clockwise in a plan view with respect to the buoyant body 2, and the other end opening forms a second water jetting port 7 for jetting a water flow in a direction for imparting a turning force counterclockwise in a plan view with respect to the buoyant body 2. A thruster 8 is provided in the tunnel-shaped flow passage 11. There are provided a yaw motion detecting sensor 9 for detecting the yaw motion of the buoyant body 2, and a controller 10 for giving a command to the thruster 8 based on a signal. When the yaw motion of the spar type floating body 1 is detected by the yaw motion detecting sensor 9, the thruster 8 is started by the controller 10, the water flow is jetted in the direction for imparting the turning force in a direction for canceling the yaw motion by the water jetting port 6 or 7, and the yaw motion generated in the spar type floating body 1 is controlled thereby.

Description

  The present invention relates to a swing control device for a floating body used for suppressing the swing in the yaw direction that occurs in a spar type floating body.

  One type of floating body used to install an offshore structure in a state of floating on the sea surface is a spar type (cylinder buoy type) floating body.

  The spar type buoyant body includes a buoyant body having a cylindrical shape, and includes a ballast at one end in the axial direction of the buoyant body, for example, a ballast of a type in which ballast water is injected into a ballast tank. The center of the buoyancy and the position of the center of gravity are shifted in the axial direction, and the position of the center of gravity falls below the center of the buoyancy, so that the buoyancy body is upright in the axial direction, that is, in the vertical direction It is designed to float on the sea surface in an extended posture. The buoyancy body in the spar-type floating body may be any shape as long as the outer shape is substantially cylindrical, and the cylindrical buoyancy body includes a portion having a partially different diameter in the axial direction. Or a type having a structure in which a buoyant body divided body manufactured in a state of being divided into a plurality of parts in the axial direction is connected via a connecting means, or a lower end side of the buoyant body. A type with a structure in which a ballast or ballast tank manufactured separately is attached to one end side in the axial direction via an attachment means, or a protruding part that protrudes outward on the cylindrical outer peripheral surface of the buoyancy body Including the form with

  Furthermore, the spar-type floating body has a circumferential position at a height position that is the point of application of the fluid force in the buoyant body so that a tilting moment does not act on the buoyant body due to an imbalance between mooring force and fluid force during tidal currents. One end of an individual mooring line (anchor rope) extending along the radial direction of the spar type floating body in a plan view at three or four, or more than five, at approximately equal intervals in the direction. Each of the mooring lines is connected to each other, and the other end of each mooring line is connected to a anchor (anchor) installed on the seabed, and the spar type floating body is catenary moored by each mooring line and the anchor. In many cases (for example, refer to Patent Document 1). Thus, in the state where the spar type floating body is catenary moored, the position of the spar type floating body is held by the balance of the catenary generated by its own weight on each mooring line connected to a plurality of locations in the circumferential direction of the buoyant body. When an external force due to tidal currents, waves, or wind acts on the spar type floating body, the catenary of each mooring line changes according to the magnitude of the external force and the direction in which the spar type floats. The external force acting on the floating body can be received.

  It has been proposed in the past that an offshore platform equipped with a plurality of thrusters can maintain the orientation of the offshore platform in a certain target orientation by controlling each of the above thrusters in accordance with fluctuations in environmental disturbances. (For example, see Patent Document 2).

JP 2009-248792 A JP 2002-173086 A

  However, since the spar type floating body described above has a cylindrical buoyancy body, the influence of waves and wind on the buoyancy body itself may cause a force to act on the buoyancy body at a position shifted from the axial center position. Although not so much, depending on the shape and structure of the offshore structure provided on the upper side of the spar type floating body, a wave or wind hits the offshore structure. A force may be applied to a position deviated from the axial center position. When such a force deviated from the axial center position is applied, the buoyancy body may be operated in the yaw direction.

  Further, when the spar type floating body is moved in the yaw direction as described above, it is based on the catenary balance between the mooring lines rather than the mooring lines used for the catenary mooring of the spar type floating body. Because the force to return will act, the restoring force to restore the original movement in the yaw direction generated in the spar type floating body will act, but depending on how the restoring force works In this case, the spar type floating body may swing in the yaw direction, and the swing in the yaw direction may be amplified.

  By the way, the offshore structure provided on the upper side of the spar-type floating body is a type of offshore structure that is required to keep the offshore structure constant in a state in which the orientation of the offshore structure is oriented in a certain direction because of its function and structure. In the case of an object, it is required to suppress the swing in the yaw direction of the spar type floating body as described above. However, in reality, no means has been proposed for preventing the spar-type floating body from swinging in the yaw direction.

  In addition, although patent document 1 has description about a spar type floating body, about the spar type floating body, there is no description about the means for making it possible to suppress the rocking | fluctuation of a yaw direction, and it is not suggested. .

  On the other hand, Patent Document 2 discloses the idea of maintaining the orientation of the offshore platform in a certain target direction, but this measures disturbances such as wind, waves, and tidal currents that act on the unsealed offshore platform. The thrust of a plurality of thrusters provided on the offshore platform is obtained after evaluating the influence, and the swing of the spar-type floating body moored in the catenary is suppressed in the yaw direction. It cannot be applied as it is.

  Therefore, the present invention is capable of suppressing the yaw-direction oscillation generated in the spar-type floating body, and is advantageous for keeping the orientation of the offshore structure provided above the spar-type floating body constant. An object of the present invention is to provide a floating body swing control device that can perform the above-described operation.

  In order to solve the above-mentioned problem, the present invention corresponds to claim 1, wherein the buoyant body has an outer peripheral portion of a submerged portion of the buoyant body in a spar type floating body provided with a buoyant body extending in the vertical direction. On the other hand, a first water injection port for injecting a water flow in a direction in which a turning force in a clockwise direction in a plan view is applied, and a direction in which a turning force in a counterclockwise direction in a plan view is applied to the buoyancy body A water flow supply means provided with a second water injection port for injecting a water flow to the first water injection port and capable of selectively supplying the water flow to either the first water injection port or the second water injection port; And providing a command to the water flow supply means based on a yaw motion detection sensor for detecting motion in the yaw direction generated in the spar type floating body and a signal input from the yaw motion detection sensor. The configuration includes a controller.

  Further, in the above configuration, the water flow supply means is provided with a thruster in a tunnel-like channel provided so as to connect the first water injection port and the second water injection port to the outer peripheral portion of the buoyancy body. And

  Similarly, in the above configuration, the water flow supply means is connected to the pump provided in the water pipe connected to the water intake provided in the submerged portion of the buoyancy body, and the downstream side of the water pipe is connected to the first water injection port. And a flow path switching valve provided at a branch portion for branching to the branch pipe connected to the second water injection port.

  The floating body swing control device of the present invention exhibits the following excellent effects.

  In a spar type floating body having a buoyancy body extending in the vertical direction, a water flow is jetted in a direction in which a clockwise turning force is applied to the buoyancy body in a plan view in a clockwise direction. And a second water injection port for injecting a water flow in a direction to apply a counterclockwise turning force to the buoyant body in a plan view. A water flow supply means capable of selectively supplying a water flow to either one of the water injection port and the second water injection port, and further for detecting an operation in the yaw direction generated in the spar type floating body. Based on a yaw motion detection sensor and a controller for giving a command to the water flow supply means based on a signal input from the yaw motion detection sensor, the yaw motion fluctuation generated in the spar type floating body is provided. Movement can be suppressed. Therefore, it can be advantageous to keep the orientation of the offshore structure provided above the spar type floating body constant.

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 shows an embodiment of a swing control device for a floating body of the present invention, in which (A) is a schematic side view, and (B) is a view taken in the direction of arrows A-A in (A). FIG. 3 shows another example of the arrangement of the tunnel-shaped flow path provided with the thruster in the apparatus of FIG. 1, (A) is a schematic side view, and (B) is a view taken in the direction of arrows BB in (A). It is a figure corresponding to FIG. 1 (B) which shows another example of arrangement | positioning of the tunnel-shaped flow path provided with the thruster in the apparatus of FIG. It is a figure which shows the flow of the control procedure of the controller in the apparatus of FIG. The other form of implementation of this invention is shown, (A) is a partially cut | disconnected schematic side view, (B) (C) is CC arrow view of (A), (B) is 1st The figure which shows the state which injects a water flow from a water injection port, (c) is a figure which shows the state which injects a water flow from a 2nd water injection port. It is a figure which shows the outline | summary of the control system in the apparatus of FIG. It is a figure which shows the flow of the control procedure of the controller in the apparatus of FIG.

  Hereinafter, embodiments for carrying out the present invention will be described with reference to the drawings.

  1 (a) (b) to FIG. 4 show a case where the present invention is applied to a spar type floating body as shown in FIGS. The configuration is as follows.

  Here, first, an outline of the configuration of the spar type floating body 1 shown in FIGS. The spar type floating body 1 includes, for example, a ballast 3 of a type in which ballast water is injected into a ballast tank (not shown) as a ballast 3 at a lower end portion of a columnar buoyancy body 2 extending in the vertical direction. 2 can be floated offshore (sea surface) with its axial direction upright.

  Further, on the outer peripheral portion of the buoyancy body 2 at a predetermined height position corresponding to the point of application of the fluid force in the buoyancy body 2, in the radial direction about the buoyancy body 2 in plan view at intervals of 90 degrees in the circumferential direction. Attaching one end (inner end) of each of the four mooring lines 4 arranged to extend, and the other end (outer end) of each mooring line 4 is an individual anchor (anchor) installed on the seabed The spar type floating body 1 is catenary moored via the four mooring lines 4.

  The swing control device for a floating body of the present invention applied to a spar type floating body 1 having such a configuration is arranged in a clockwise direction in a plan view with respect to the buoyant body 2 on the outer periphery of the submerged portion of the buoyant body 2. A water injection port (hereinafter referred to as a first water injection port) 6 for injecting a water flow in a direction in which a turning force is applied and a turning force in a counterclockwise direction in a plan view are applied to the buoyant body 2. An injection port (hereinafter referred to as a second water injection port) 7 is provided for injecting a water flow in the direction in which the water flows.

  A water flow supply means 8 that can selectively supply a water flow to one of the first water injection port 6 and the second water injection port 7 is connected.

  Further, a yaw motion detection sensor 9 for detecting the motion of the spar floating body 1 in the yaw direction is provided at any part of the spar floating body 1, for example, the buoyancy body 2, and the yaw motion detecting sensor 9 is provided. Based on the detection signal of the yaw motion of the spar type floating body 1 input from the motion detection sensor 9, a controller 10 is provided that gives a command to the water flow supply means 8.

  More specifically, a tunnel-like flow path 11 that penetrates in the horizontal direction perpendicular to the radial direction of the buoyancy body 2 is provided at the outer periphery of the submerged portion of the buoyancy body 2 as shown in FIG. The opening on one end side of the tunnel-shaped flow path 11 serves as the first water injection port 6, and the opening on the other end side of the tunnel-shaped flow path 11 serves as the second water injection port 7. .

  Furthermore, a thruster 8 capable of switching the direction of the water flow generated in the tunnel-shaped flow path 11 in both directions is provided as the water flow supply means in the longitudinal intermediate portion of the tunnel-shaped flow path 11 ( For convenience of explanation, the thrusters are given the same reference numerals as the water flow supply means described above).

  The tunnel-shaped flow path 11 equipped with the thruster 8 operates when the thruster 8 is operated to eject a water flow from the first water injection port 6 or the second water injection port 7 of the tunnel-shaped flow path 11. Further, from the viewpoint of preventing the spar-type floating body 1 itself from causing an operation of tilting the axial center of the buoyant body 2 such as pitching or rolling, each of the water injection ports 6 and 7 has the above buoyant body. It is desirable that it is disposed in the vicinity of a predetermined height position corresponding to the point of application of the fluid force in 2.

  Further, when the thruster 8 is operated and a water flow is jetted from the first water jet port 6 or the second water jet port 7 of the tunnel-shaped channel 11, a lateral flow (sway) is caused to the spar type floating body 1 itself. From the viewpoint of preventing the occurrence of the above, it is desirable to provide a plurality of tunnel-shaped flow paths 11 equipped with the thrusters 8 at the outer peripheral portion of the buoyancy body 2 at equal intervals in the circumferential direction.

  Specifically, for example, as shown in FIGS. 1 (a) and 1 (b), a tunnel-like flow path 11 equipped with the thruster 8 at two locations facing each other 180 degrees in the circumferential direction on the outer peripheral portion of the buoyancy body 2. May be provided respectively.

  Further, as shown in FIGS. 2 (a) and 2 (b), tunnel-like flow passages 11 equipped with the thrusters 8 are provided at four locations at intervals of 90 degrees in the circumferential direction on the outer peripheral portion of the buoyancy body 2, respectively. Also good. In this case, when the arrangement of the four tunnel-like flow paths 11 provided at intervals of 90 degrees in the circumferential direction of the buoyancy body 2 overlaps in plan view, the tunnel-like flow paths 11 are prevented from crossing each other. In order to prevent the strength of the buoyant body 2 from decreasing due to the provision of the respective tunnel-shaped flow paths 11, a pair of tunnel-shaped flow paths 11 arranged at intervals of 180 degrees in the circumferential direction of the buoyancy body 2. The height position may be shifted in the vertical direction of the buoyancy body 2.

  Further, although not shown in the figure, tunnel-like flow paths 11 equipped with the thrusters 8 may be provided at three locations at 120 ° intervals in the circumferential direction on the outer periphery of the buoyancy body 2. On the other hand, as described above, the spar type floating body 1 is catenary moored by the four mooring lines 4, so that each mooring line 4 can sufficiently flow the lateral flow of the spar type floating body 1. It is desirable that the spar-type floating body 1 suppresses the fluctuation in the yaw direction when it can be suppressed, but for an offshore structure having a form and function that can tolerate the lateral flow. In the case of a floating body, as shown in FIG. 3, a tunnel-like flow path 11 equipped with a thruster 8 similar to the above may be provided at one location on the outer periphery of the buoyancy body 2.

  The yaw motion detection sensor 9 uses a gyro sensor, for example, to detect the acceleration in the yaw direction of the buoyant body 2 of the spar type floating body 1 and sends the detection signal to the controller 10. Thus, with respect to the yaw motion generated in the spar type floating body 1 integral with the buoyancy body 2, the speed and the amount of movement (swing angle) can be detected.

  The yaw motion detection sensor 9 detects the amount of change caused by the motion in the yaw direction generated in the spar type floating body 1 and sends the detection signal to the controller 10, so that the spar type floating body 1 Any type of sensor other than the gyro sensor may be used as long as the generated movement in the yaw direction can be detected.

  When the controller 10 receives a signal from the yaw motion detection sensor 9 (step 1: S1) as shown in the flowchart of the processing procedure in FIG. 4, based on the input signal, The direction and amount of yaw motion generated in the spar type floating body 1 are detected (step 2: S2).

  Next, the controller 10 determines whether or not the amount of yaw movement of the spar type floating body 1 detected in step 2 (S2) has exceeded a preset threshold value (step 3). : S3). It should be noted that whether or not the threshold value set in advance in step 3 (S3) has been exceeded is suppressed as long as the amount of yaw movement of the spar-type floating body 1 is small. If the control of the thruster 8 as the water flow supply means by the controller 10 as will be described later is attempted even when the amount of yaw operation of the spar type floating body 1 is small, This is because the frequency of control becomes great. It is assumed that the threshold value is appropriately set in consideration of the amount of fluctuation in the yaw direction required for the offshore structure to which the spar type floating body 1 is applied.

  If it is determined in step 3 (S3) that the amount of movement of the spar-type floating body 1 in the yaw direction does not exceed the threshold value, the controller 10 returns to step 1 (S1), and The processing from step 1 (S1) to step 3 (S3) is repeated.

  On the other hand, if it is determined in step 3 (S3) that the amount of movement of the spar-type floating body 1 in the yaw direction exceeds the threshold value, the controller 10 goes to the thruster 8 as the water flow supply means. The thruster 8 is activated by giving a command, and the water flow generated by the thruster 8 is generated in the spar-type floating body 1 in the first water injection port 6 or the second water injection port 7. It is made to inject from the water injection port 6 or 7 of the side which can provide turning force in the direction which cancels a yaw operation (step 4: S4).

  Specifically, the spur type floating body 1 has a yaw motion in a counterclockwise direction in a plan view with a motion amount exceeding the threshold value set in step 3 (S3). If it is detected, the controller 10 gives a command to the thruster 8 and is generated by the operation of the thruster 8 as shown by the alternate long and short dash line in FIG. 1 (B), FIG. 2 (B), and FIG. The water flow to be made is jetted from the first water jet port 6. Accordingly, a turning force in the clockwise direction in a plan view is applied to the spar type floating body 1 as a reaction force for ejecting a water flow from the first water injection port 6. Due to the turning force in the clockwise direction, the yaw operation in the counterclockwise direction in the plan view generated in the spar type floating body 1 is eliminated.

  Further, when it is detected that the yaw motion in the clockwise direction in the plan view is generated in the spar type floating body 1 with the operation amount exceeding the threshold value set in the step 3 (S3). The controller 10 gives a command to the thruster 8 to generate a water flow generated by the operation of the thruster 8 as shown by a two-dot chain line in FIG. 1 (B), FIG. 2 (B), and FIG. It is made to inject from the said 2nd water injection opening 7. FIG. Accordingly, a turning force in a counterclockwise direction in a plan view is applied to the spar type floating body 1 as a reaction force for injecting a water flow from the second water injection port 7. Due to the turning force in the counterclockwise direction, the yaw motion in the clockwise direction in the plan view generated in the spar type floating body 1 is eliminated.

  Note that the thruster 8 is driven by the controller 10 according to the detection result of the yaw motion in the plan counterclockwise direction or the plan view clockwise direction generated in the spar type floating body 1 by the controller 10 as described above. As a control law when the water flow generated in 8 is jetted from the first water jet port 6 or the second water jet port 7, the yaw motion detected for the spar type floating body 1 is used. A commonly used feedback control may be applied based on the amount detection result.

  The reaction when the yaw motion generated in the spar type floating body 1 in step 4 (S4) causes the water flow generated by the thruster 8 to be jetted from the first water jet 6 or the second water jet 7. When the turning force applied to the spar-type floating body 1 as a force is eliminated, the controller 10 returns to the step 1 (S1) and repeats the above-mentioned processing sequentially.

  When the floating body swing control device of the present invention having the above-described configuration is used, the controller 10 and the yaw motion detection sensor 9 are kept in an activated state.

  In this state, when the spar-type floating body 1 swings in the yaw direction due to the influence of waves or wind, the yaw motion in the spar-type floating body 1 is detected by the yaw motion detection provided in the buoyancy body 2. It is detected by the sensor 9 for use. Further, when the yaw motion generated in the spar type floating body 1 exceeds a preset threshold value, the thruster in the tunnel-like channel 11 provided on the outer peripheral portion of the buoyant body 2 by the controller 10. A command is given to 8 to start the thruster 8, and the water flow generated by the thruster 8 is jetted from the first water jet port 6 or the second water jet port 7 of the tunnel-shaped channel 11. Thus, regardless of whether the yaw motion occurring in the spar type floating body 1 is in the counterclockwise direction in plan view or the clockwise direction in plan view, the spar type float body 1 has its yaw motion. A turning force in a direction to eliminate the problem is applied. Therefore, the yaw motion generated in the spar type floating body 1 can be reduced.

  Thus, according to the floating body swing control device of the present invention, it is possible to suppress the swing in the yaw direction that occurs in the spar-type floating body 1.

  Therefore, it can be advantageous to keep the orientation of the offshore structure provided above the spar type floating body 1 constant.

  Further, the water flow is selectively supplied from one of the first water injection port 6 and the second water injection port 7 for applying a turning force in a direction to cancel the yaw motion generated in the spar type floating body 1. Since the water flow supply means for jetting is configured to include the thruster 8 in the tunnel-like flow path 11 connecting the first water injection port 6 and the second water injection port 7, the water flow supply means The apparatus configuration can be easily realized.

  In addition, since the tunnel-like flow path 11 is provided inside the buoyancy body 2 and the thruster 8 is provided in the tunnel-like flow path, the structure generally has a lot of voids to obtain buoyancy. Thus, the internal space of the buoyant body 2 can be effectively used. Further, it is possible to eliminate the need to provide a protruding portion on the cylindrical outer shape of the buoyancy body 2 that causes the resistance of the buoyancy body 2 to change the wave or current. Further, it is possible to avoid the possibility that the thruster 8 directly hits the thruster 8 floating in the sea.

  Note that the thruster 8 has the effect of effectively utilizing the internal space of the buoyancy body 2 as described above, the effect of eliminating the need to provide a protrusion on the cylindrical outer shape of the buoyancy body 2, In order to obtain an effect that it is possible to avoid the possibility that a thing floating in the sea directly hits the thruster 8, it is desirable to equip the tunnel-like flow path 11 provided in the outer peripheral portion of the buoyancy body 2; In order to obtain only the effect of suppressing the fluctuation in the yaw direction in the spar type floating body 1 without the above effect, the outer surface of the submerged portion of the buoyant body 2 is What is necessary is just to employ | adopt the structure formed by attaching the thruster arrange | positioned in the attitude | position which can generate | occur | produce the horizontal water flow along the tangential direction of the outer peripheral surface of the buoyancy body 2.

  Next, FIGS. 5 (a), (b), (c) to FIG. 7 show other embodiments of the present invention. As shown in FIGS. 1 (a), (b) to FIG. In the configuration in which the first water injection port 6 and the second water injection port 7 are provided in the outer peripheral portion of the submerged portion of the buoyancy body 2 in the floating body 1, the first water injection port 6, A water flow supply means for selectively supplying a water flow to either one of the water injection ports 7 is provided in the tunnel-shaped flow path 11 that connects the first water injection port 6 and the second water injection port 7. Instead of the configuration provided with the thruster 8, the water flow supply means 12 is connected to a portion of the buoyant body 2, for example, a water inlet 13 provided at the bottom of the water pipe 14 provided with the pump 15. A plurality of one end portions are connected and the other end side of the water pipe 14 is in accordance with the number of both the first water injection port 6 and the second water injection port 7. Branch pipes 16 and 17 are provided, and the branch pipes 16 and 17 are connected to the first water injection port 6 and the second water injection port 7, respectively, and connected to the first water injection port 6. A flow path switching valve 18 is provided at a branch portion between the branched pipe 16 and the branch pipe 17 connected to the second water injection port 7, and the discharge of the pump 15 is performed by the switching operation of the flow path switching valve 18. The side is configured to be able to selectively communicate with either the first water injection port 6 or the second water injection port 7.

  Further, as shown in FIG. 6, based on the yaw motion detection signal of the spar type floating body 1 input from the yaw motion detection sensor 9 similar to that shown in FIG. The controller 10A having a function of giving a command to the pump 15 and the flow path switching valve 18 of the water flow supply means 12 is provided.

  More specifically, the buoyancy body 2 has the same arrangement as the buoyancy body 2 shown in FIG. 1B on the outer peripheral portion at a certain height position of the submerged portion, and the first water injection port 6. And two second water injection ports 7 are provided.

  For example, the water pipe 14 branches the upper end portion, which is the downstream end portion thereof, into two branches, and further branches the downstream end portions of the two branch pipes 19a and 19b formed by this branching into two. By doing so, two branch pipes 16 for connecting to the two first water injection ports 6 and two branch pipes 17 for connecting to the two second water injection ports 7 are formed. It is.

  The flow path switching valve 18 is provided at a branch portion between the branch pipe 16 and the branch pipe 17 at the downstream end of the two branch pipes 19a and 19b, and as shown in FIG. It is possible to switch between the state where only the branch pipe 16 is communicated with the branch pipes 19a and 19b and the state where only the branch pipe 17 is communicated with the branch pipes 19a and 19b as shown in FIG. It is like that.

  In addition, from the said 1st water injection port 6, a water flow can be injected to the direction which provides the turning force of the clockwise direction with respect to the buoyancy body 2 by planar view, and the said 2nd water injection port 7 From the downstream end of the branch pipe 16 and the downstream end of the branch pipe 17 so that the water flow can be jetted in a direction in which a counterclockwise turning force is applied to the buoyancy body 2 in plan view. As long as the orientation of the part is set, the upstream end of the branch pipe 16 and the upstream end of the branch pipe 17 may be in any arrangement other than the arrangement in a straight line.

  If the water pipe 14 can be selectively communicated with either the first water injection port 6 or the second water injection port 7, the downstream end of the water pipe 14 is provided. One flow path switching valve 18 is provided at a portion where the portion is branched into two branch pipes, a plurality of the first water injection ports 6 are connected to the downstream side of one branch pipe, and the downstream of the other branch pipe. A plurality of the second water injection ports 7 may be connected to the side.

  Further, as the arrangement of the first water injection port 6 and the second water injection port 7 in the present embodiment, the same arrangement as shown in FIG. 2 (b) and the same arrangement as shown in FIG. May be adopted. In the case of adopting these configurations, the number of the first water injection ports 6 and the second water injection ports 7 changes, but the first connected to the downstream side of the water pipe 14 according to the number. It is only necessary to change the number of branch pipes 16 for communicating with one water jet port 6 and the branch pipes 17 for communicating with the second water jet port 7. Further, the flow path switching valve 18 is connected to the water pipe 14. As long as it can be selectively communicated with either the first water injection port 6 or the second water injection port 7.

  As shown in the flowchart of the processing procedure in FIG. 7, the controller 10A receives a signal from the yaw motion detection sensor 9 in the same manner as in Step 1 (S1) to Step 3 (S3) in FIG. Then (step 1: S1), based on the input signal, the direction and amount of yaw motion generated in the spar type floating body 1 are detected (step 2: S2), and the detected spar type It is determined whether or not the amount of yaw movement of the floating body 1 exceeds a preset threshold value (step 3: S3), and the amount of movement of the spar-type floating body 1 in the yaw direction is the threshold value. When it is determined that the value does not exceed, the controller 10A returns to step 1 (S1) and repeats the processing from step 1 (S1) to step 3 (S3).

  On the other hand, if it is determined in step 3 (S3) that the amount of movement of the spar type floating body 1 in the yaw direction exceeds the threshold value, the controller 10A causes the pump 15 of the water flow supply means 12 to A command is given to start the pump 15, and a command is given to the flow path switching valve 18 to switch the pump 15 to the first water injection port 6 or the first water injection port 6. Among the two water injection ports 7, the water injection port 6 or 7 on the side where the turning force can be applied in the direction to cancel the yaw motion generated in the spar type floating body 1 is communicated (step 4A: S4A). .

  Specifically, the spur type floating body 1 has a yaw motion in a counterclockwise direction in a plan view with a motion amount exceeding the threshold value set in step 3 (S3). If detected, the controller 10A gives a command to the pump 15 to start it, and as shown in FIG. 5B, the water flow generated by the operation of the pump 15 causes the first water injection. The flow path switching valve 18 is switched so as to be guided to the port 6. Thereby, since a water flow comes to be injected from the said 1st water injection port 6, it is a plane as reaction force of injecting a water flow from the said 1st water injection port 6 with respect to the said spar-type floating body 1. FIG. A turning force in the clockwise direction is applied, and the turning force in the clockwise direction in the plan view cancels the yaw motion in the counterclockwise direction in the plan view generated in the spar type floating body 1.

  Further, when it is detected that the yaw motion in the clockwise direction in the plan view is generated in the spar type floating body 1 with the operation amount exceeding the threshold value set in the step 3 (S3). The controller 10A gives a command to the pump 15 to start it, and the water flow generated by the operation of the pump 15 is guided to the second water injection port 7 as shown in FIG. The flow path switching valve 18 is switched in such a manner. Thereby, since a water flow comes to be injected from the said 2nd water injection port 7, it is a plane as reaction force of injecting a water flow from the said 2nd water injection port 7 with respect to the said spar-type floating body 1. FIG. A turning force in the counterclockwise direction in view is applied, and the turning force in the counterclockwise direction in plan view eliminates the yaw motion in the clockwise direction in the plan view generated in the spar type floating body 1.

  In addition, the controller 15A drives the pump 15 according to the detection result of the counterclockwise direction in the plan view or the clockwise direction in the plan view generated in the spar type floating body 1 by the controller 10A. As a control law for switching the switching valve 18 so that the water flow generated by the pump 15 is injected from the first water injection port 6 or the second water injection port 7, the spur type is used. A commonly used feedback control may be applied on the basis of the detection result of the amount of yaw motion detected for the floating body 1.

  The spur type floating body as a reaction force when the yaw motion generated in the spar type floating body 1 in the step 4A (S4A) causes the water flow to be jetted from the first water jet port 6 or the second water jet port 7. When the turning force is applied to the controller 1, the controller 10A returns to step 1 (S1) and sequentially repeats the above-described processing.

  Other configurations are the same as those shown in FIGS. 1A and 1B, and the same components are denoted by the same reference numerals.

  When the floating body swing control device of the present embodiment having the above-described configuration is used, the controller 10A and the yaw motion detection sensor 9 are kept in an activated state.

  In this state, when the spar-type floating body 1 swings in the yaw direction due to the influence of waves or wind, the yaw motion in the spar-type floating body 1 is detected by the yaw motion detection provided in the buoyancy body 2. It is detected by the sensor 9 for use. Further, when the yaw motion generated in the spar type floating body 1 exceeds a preset threshold value, the controller 10A gives a command to the pump 15 to start the pump and A command is given to the path switching valve 18 so that the flow path switching valve 18 can inject the water flow so that the pump 15 applies a turning force in a direction to cancel the yaw motion generated in the spar type floating body 1. Since the water flow generated by the pump 15 is jetted from the first water jet port 6 or the second water jet port 7, the water flow is switched to communicate with the water jet port 6 or 7 on the side. Whether the yaw motion occurring in the spar type floating body 1 is in either the counterclockwise direction in plan view or the clockwise direction in plan view, the spar type float body 1 has a direction to cancel the yaw motion. The turning force of Uninari, therefore, becomes a yaw behavior occurring in the floating body 1 of the spar is reduced.

  As described above, the floating body swing control device according to the present embodiment can also suppress the swing in the yaw direction generated in the spar type floating body 1, and the marine structure provided above the spar type floating body 1. It can be advantageous to keep the direction of the object constant.

  In addition, this invention is not limited only to the said embodiment, The 1st water-injection port 6 and the 2nd water-injection port 7 are multistage in the up-down direction in the buoyancy body 2 in the spar type | mold floating body 1. FIG. You may make it provide in.

  Although the first water injection port 6 and the second water injection port 7 are shown as round shapes, the water flow is applied so as to apply a turning force in a clockwise direction and a counterclockwise direction in a plan view to the spar type floating body, respectively. Any shape other than a circle such as a rectangle or a slit may be used.

  5 (a) (b) (c) to FIG. 7, the water intake 13 connecting the water pipe 14 provided with the pump 15 in the water flow supply means 12 has the internal structure of the buoyancy body 2 and the You may arrange | position in the arbitrary locations of the submerged part of the buoyancy body 2 according to arrangement | positioning of the apparatus provided inside a buoyancy body.

  5 (a) (b) (c) through FIG. 7, when the spar type floating body 1 is provided with a ballast of the type in which ballast water is injected into the ballast tank as the ballast 3, It is good also as a structure which used the pump 15 with which it equips 14 with the pump normally equipped for the adjustment of the injection quantity of the ballast water with respect to the said ballast tank. In this case, a flow path switching mechanism for switching between a state in which the pump 15 and the ballast tank are in communication with each other and a state in which the pump 15 is in communication with the first water injection port 6 and the second water injection port 7. Should be provided. Furthermore, in order to eliminate the yaw motion generated in the spar type floating body 1 by using a part of the ballast water stored in the ballast tank, the first water injection port 6 and the second water injection are performed. A water flow may be jetted from the mouth 7.

  Of course, various modifications can be made without departing from the scope of the present invention.

DESCRIPTION OF SYMBOLS 1 Spar type floating body 2 Buoyancy body 6 1st water injection port 7 2nd water injection port 8 Thruster (water flow supply means)
9 Sensor for detecting yaw motion 10, 10A Controller 11 Tunnel-shaped flow path 12 Water flow supply means 13 Water inlet 14 Water pipe 15 Pump 16 Branch pipe 17 Branch pipe 18 Flow path switching valve

Claims (3)

  In a spar type floating body having a buoyancy body extending in the vertical direction, a water flow is jetted in a direction in which a clockwise turning force is applied to the buoyancy body in a plan view in a clockwise direction. And a second water injection port for injecting a water flow in a direction to apply a counterclockwise turning force to the buoyant body in a plan view. A water flow supply means capable of selectively supplying a water flow to either one of the water injection port and the second water injection port, and further for detecting an operation in the yaw direction generated in the spar type floating body. A floating body swing control device comprising: a yaw motion detection sensor; and a controller for giving a command to the water flow supply means based on a signal input from the yaw motion detection sensor.   The water flow supply means is configured to be provided with a thruster in a tunnel-like flow path provided so as to connect the first water injection port and the second water injection port to the outer peripheral portion of the buoyancy body. Floating body swing control device.   The water flow supply means includes a pump provided in a water pipe connected to a water intake provided in a submerged portion of the buoyancy body, a branch pipe connected to the first water injection port on the downstream side of the water pipe, and a second pipe The floating body swing control device according to claim 1, further comprising a flow path switching valve provided at a branch portion for branching to a branch pipe connected to the water injection port.

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