JP2018154197A - Friction reduction device for vessel - Google Patents

Abstract

PROBLEM TO BE SOLVED: To improve freedom in design by reducing composing members arranged inboard as well as suppressing strength degradation at a bottom in a friction reduction device for a vessel.SOLUTION: A friction reduction device is provided with: an air supply device 32 provided inside a hull 10; a passage member (air passage) 41 as an air blowing out unit 35 provided along a vessel width direction outside a bottom 13; a plurality of air blowing out openings 44 provided with prescribed intervals in the longitudinal direction of the passage member 41; and an air supply pipe 34 for connecting the air supply device 32 and the passage member 41 inboard.SELECTED DRAWING: Figure 3

Description

  The present invention relates to a ship friction reducing device that reduces frictional resistance acting on a ship hull.

  As a technique for reducing the frictional resistance acting on the hull of a ship, a technique is known in which air (bubbles) is blown into water to cover the surface of the hull with bubbles. This hull frictional resistance reduction device is provided with a gas chamber (air chamber) on the inner side of the ship bottom, and a gas supply pipe is connected to the gas chamber, and a plurality of air jets are provided on the outer plate of the ship bottom in the gas chamber. Configured. Therefore, the air supplied from the gas supply pipe to the gas chamber is diffused in the gas chamber and ejected into the water from each air ejection port. As such a hull frictional resistance reduction device, for example, there is one described in Patent Document 1 below.

JP 2010-120607 A

  In the conventional hull frictional resistance reducing device described above, a gas chamber for storing air is provided on the inner side of the ship bottom, so that a space for installing the gas chamber in the ship is required. Therefore, there is a problem that the installation space of other constituent members is limited by the installation of the gas chamber, and the degree of freedom in design is limited. In addition, there is a problem that the strength of the bottom of the ship is lowered because it is necessary to provide a plurality of air outlets at predetermined intervals in the ship width direction on the outer plate part of the bottom of the ship in the gas chamber.

  SUMMARY OF THE INVENTION The present invention solves the above-described problems, and an object thereof is to provide a ship friction reduction device that improves the degree of freedom of design by reducing the number of components arranged in the ship and suppresses the decrease in strength of the ship bottom. To do.

  In order to achieve the above object, a ship friction reducing device according to the present invention includes an air supply device provided inside a hull, an air passage provided outside the ship bottom along the ship width direction, and a longitudinal length of the air passage. And a plurality of air outlets provided at predetermined intervals in the direction, and an air supply pipe for connecting the air supply device and the air passage in a ship.

  Accordingly, air from the air supply device is supplied to an air passage provided outside the ship bottom through an air supply pipe arranged in the ship, and is blown into the water from a plurality of air outlets, thereby causing bubbles on the surface of the ship bottom. Thus, the frictional resistance can be reduced by covering. At this time, since the air passage is provided outside the ship bottom, it is not necessary to provide a gas chamber or the like in the ship, and the number of structural members arranged in the ship can be reduced and the degree of design freedom can be improved. It is not necessary to provide a large number of air outlets, and a decrease in strength of the ship bottom can be suppressed.

  In the ship friction reducing device according to the present invention, the air supply pipe is disposed in the ship, one end is connected to the air supply device, and the other end is at least in the longitudinal end or intermediate portion of the air passage. It is characterized by being connected.

  Therefore, by connecting the air supply device in the ship and the air passage outside the ship bottom by the air supply pipe in the ship, the number of components arranged in the ship can be reduced with the arrangement length of the air supply pipe being minimized. Can do.

  In the ship friction reducing device of the present invention, the air supply pipe is characterized in that the other end portion is branched into a plurality and connected to at least both longitudinal ends of the air passage.

  Therefore, the air branches from the air supply pipe and is supplied to both ends of the air passage, reducing the supply pressure difference in the longitudinal direction of the air passage, and reducing the amount of air blown into the water from a plurality of air outlets. It can be made uniform.

  In the ship friction reducing device of the present invention, a plurality of the air passages are provided outside the bottom of the ship at predetermined intervals in the width direction of the ship, and the air supply pipe has a plurality of the other ends branched into a plurality of the air passages. It is characterized by being connected to an air passage.

  Accordingly, the air is branched from the air supply pipe and supplied to the plurality of air passages, and the amount of air blown into the water from the plurality of air outlets can be made uniform in the ship width direction of the ship bottom. .

  In the ship friction reducing device of the present invention, a flow rate adjusting valve is provided in a branch pipe in which the other end of the air supply pipe branches into a plurality.

  Therefore, by adjusting the amount of air supplied to the plurality of air passages by the flow rate adjustment valve, it is possible to set the optimum air blowing amount according to the hull shape and the navigational state of the ship.

  In the ship friction reducing device according to the present invention, the air passage is provided in a flat outer surface portion of the ship bottom.

  Therefore, air is blown out into the water from the plurality of air outlets toward the flat outer surface portion of the ship bottom, and the air can be appropriately diffused into the flat outer surface portion of the ship bottom, and the frictional resistance can be efficiently reduced.

  In the ship friction reducing device of the present invention, the air supply pipe is characterized in that the other end of the air supply pipe passes through the ship bottom outer plate and is connected to the air passage.

  Therefore, the other end portion of the air supply pipe penetrates the ship bottom outer plate and is connected to the air passage, whereby the air supply pipe and the air passage can be connected in a watertight manner.

  In the ship friction reducing device of the present invention, the air supply pipe is characterized in that an outer diameter dimension is set to be smaller than a width dimension in the ship length direction in the air passage.

  Therefore, when the air is supplied from the air supply pipe to the air passage, the flow passage area is enlarged, so that the air can be easily diffused in the air passage and blown out into the water from a plurality of air outlets. The amount of air can be made uniform.

  In the ship friction reducing device of the present invention, the air passage is characterized in that a cross-sectional shape along the ship length direction is a semicircular shape.

  Therefore, by making the cross-sectional shape of the air passage into a semicircular shape, it is possible to process and use an existing pipe or the like as the air passage, and to suppress an increase in manufacturing cost.

  In the friction reducing device for a ship according to the present invention, the air passage has a semi-oval shape or a semi-elliptical shape in which a cross-sectional shape along the ship length direction is long in the ship length direction.

  Therefore, by making the cross-sectional shape of the air passage into a semi-oval or semi-elliptical shape that is long in the ship length direction, it is possible to reduce the amount of protrusion from the ship bottom and suppress an increase in navigation resistance.

  In the friction reducing apparatus for a ship according to the present invention, the plurality of air outlets are provided on the stern side in the air passage.

  Therefore, the air is blown out from the air outlet into the water on the stern side, and the bubbles can be appropriately diffused along the outer surface portion of the bottom of the ship.

  In the ship friction reducing device according to the present invention, the plurality of air outlets have an opening area that increases as the air outlets are separated from the connection portion of the air supply pipe in the air passage.

  Therefore, the air supplied from the air supply pipe to the air passage has a high pressure in the vicinity of the connection portion, but is difficult to go out into the water near the connection portion and easily out into the water at a position away from the connection portion. The amount of air blown out into the water from the air outlet can be made uniform.

  According to the ship friction reducing device of the present invention, it is possible to improve the degree of design freedom by reducing the number of components arranged in the ship, and to suppress a decrease in strength of the ship bottom.

FIG. 1 is a schematic side view of a ship equipped with the ship friction reducing device of the first embodiment. FIG. 2 is a schematic bottom view of a ship equipped with a ship friction reduction device. FIG. 3 is a schematic longitudinal sectional view of a ship equipped with a ship friction reduction device. 4 is a cross-sectional view taken along the line IV-IV in FIG. FIG. 5 is a schematic longitudinal sectional view of a ship showing a modification of the air supply pipe in the ship friction reducing device of the first embodiment. FIG. 6 is a cross-sectional view illustrating a modification of the air blowing portion in the ship friction reducing device of the first embodiment. FIG. 7 is a longitudinal sectional view of a ship equipped with the ship friction reducing device of the second embodiment. FIG. 8 is a longitudinal sectional view of a ship showing a modification of the air supply pipe in the ship friction reducing device of the second embodiment. FIG. 9 is a longitudinal sectional view of a ship equipped with the ship friction reducing device of the third embodiment. FIG. 10 is a system diagram showing an air supply path.

  Exemplary embodiments of a ship friction reducing device according to the present invention will be explained below in detail with reference to the accompanying drawings. In addition, this invention is not limited by this embodiment, and when there are two or more embodiments, what comprises combining each embodiment is also included.

[First Embodiment]
FIG. 1 is a schematic side view of a ship equipped with the ship friction reducing device of the first embodiment, and FIG. 2 is a schematic bottom view of the ship equipped with the ship friction reducing device.

  As shown in FIGS. 1 and 2, the ship equipped with the ship friction reducing device of the first embodiment is, for example, a passenger ship (car ferry), and the hull 10 includes a bow 11, a stern 12, and a ship bottom. 13, port (ship side) 14 and starboard (ship side) 15. In this embodiment, the ship length direction (front-rear direction) of the hull 10 is represented as the X direction, the ship width direction (width direction) as the Y direction, and the ship height direction (up and down direction) as the Z direction. CL represents the center line of the hull 10, and WL represents the full load water line of the hull 10.

  In the hull 10, an engine room 17 is partitioned by a partition wall 16 on the stern 12 side, and a main engine (for example, a diesel engine) 18 is disposed in the engine room 17. The main engine 18 is drivingly connected to a propeller 19 that transmits propulsive force. Further, the hull 10 is provided with a rudder 20 for controlling the direction of the hull 10 at the stern 12.

  Further, the hull 10 includes an air supply equipment room 21, a hold 22, a vehicle deck 23, a lamp 24, a deck exposure part 25, a partition wall 26, a ship bottom skin 27, and ship side skins 28 and 29. Have. The air supply device room 21 is arranged on the bow 11 side from the hold 22. The air supply equipment room 21 and the hold 22 are partitioned by a partition wall 26. The vehicle deck 23 forms the floor surfaces of the air supply equipment room 21 and the hold 22. The ramp 24 is used for an automobile (not shown) to get on and off the hold 22. The deck exposure unit 25 is, for example, the upper deck of the bow 11 and is disposed above the air supply device room 21.

  The friction reducing device 31 includes an air supply device 32, an air suction port 33, an air supply pipe 34, and an air blowing portion 35. The air supply device 32 is a compressor or a blower and is installed in the air supply device chamber 21. The air suction port 33 is disposed in the deck exposure unit 25. The air blowing portion 35 is disposed on the ship bottom 13 (the ship bottom outer plate 27) on the bow 11 side. The air supply pipe 34 connects the air supply device 32 and the air blowing part 35.

  The air blowing portion 35 is disposed, for example, on the center line CL of the hull 10 and is disposed on a flat portion of the ship bottom outer plate 27 on the ship bottom 13. In addition, although the air blowing part 35 was arrange | positioned in the flat part of the ship bottom 13 (boat bottom outer plate 27) by the side of the bow 11, the air blowing part 35, 36 may be arranged. In this case, it is desirable to provide a plurality (two in this embodiment) of air blowing portions 36 with a predetermined interval in the ship width direction Y, but one air blowing portion 36 may be provided. Moreover, you may arrange | position an air blowing part in each ship side skin | plate 28,29 of the port 14 and starboard 15 in the bow 11 side.

  The air supply device 32 pressurizes the air sucked from the air suction port 33 and supplies the pressurized compressed air to the air blowing section 35 (36). The air blowing part 35 (36) blows out the compressed air supplied from the air supply device 32 through the air supply pipe 34 into the water. That is, air is blown out into the water from the air blowing portion 35 (36) of the hull 10, bubbles formed by the blown air are sent out to the flat portion of the ship bottom 13, and the hull 10 is covered by the bubbles. The frictional resistance of the hull 10 is reduced.

  Here, the air supply pipe 34 and the air blowing part 35 will be described in detail. FIG. 3 is a schematic longitudinal sectional view of a ship equipped with a ship friction reducing device, and FIG. 4 is a sectional view taken along line IV-IV in FIG.

  The air blowing part 35 is provided in the flat outer surface part of the ship bottom 13 along the ship width direction Y as an air passage of the present invention. The air blowing portion 35 is a passage member 41 having a semicircular cross-sectional shape along the ship length direction X, and is formed, for example, by dividing a circular pipe into two in the radial direction. The end of the passage member 41 is in contact with the outer surface of the ship bottom skin 27 and is fixed by welding. Further, each end of the passage member 41 in the longitudinal direction is closed by a closing plate (not shown). At this time, the passage member 41 is provided with a seal member (not shown) between the outer surface portion of the ship bottom outer plate 27, so that a sealed passage 42 is secured.

  The air supply pipe 34 is disposed inside the hull 10, one end 34 a is connected to the air supply device 32, the other end is branched into two branch pipes 34 b, and the longitudinal direction in the passage member 41 (the ship width direction) Y) is connected to each end. A through hole 43 is formed in the ship bottom outer plate 27 at a position corresponding to each end of the passage member 41 in the longitudinal direction. Each branch pipe 34b has an end fitted into the through hole 43 and is fixed by welding. Therefore, the air supply device 32 communicates with the passage 42 of the passage member 41 through the air supply pipe 34 and each branch pipe 34b. In this case, the air supply pipe 34 (branch pipe 34 b) has an outer diameter dimension that is smaller than the width dimension in the ship length direction X of the passage member 41.

  The passage member 41 is provided with a plurality of air outlets 44 at predetermined intervals in the longitudinal direction. The plurality of air outlets 44 are provided on the stern 12 side of the passage member 41 so as to open toward the outer surface portion of the bottom bottom plate 27 on the stern 12 side from the passage member 41. The plurality of air outlets 44 are set so that the opening area increases as the distance from the connecting portion of the branch pipe 34 b in the passage member 41 increases. That is, the passage member 41 has a small opening area of the air outlet 44 close to each end to which the branch pipe 34b is connected, and the opening of the intermediate air outlet 44 away from each end to which the branch pipe 34b is connected. The area is getting bigger. In this case, the displacement of the opening area of the air outlet 44 may be gradually displaced or may be displaced stepwise.

  Therefore, when the air supply device 32 is activated, the air supply device 32 pressurizes the air sucked from the air suction port 33 and supplies the compressed air from the air supply pipe 34 to each end of the passage member 41 through each branch pipe 34b. To do. The compressed air supplied to the passage member 41 is blown out into the water from the plurality of air outlets 44 while flowing through the passage 42 from the respective end portions to the intermediate portion side. At this time, the plurality of air blowing ports 44 have a large opening area from the end portion to the middle portion of the passage member 41, so that the amount of compressed air blown into the water from each air blowing port 44 is made uniform. The compressed air blown into the water from each air outlet 44 becomes bubbles, flows backward in the flat part of the ship bottom 13 and diffuses in the width direction, and flows backward in the hull 10 along the flat part of the ship bottom 13. .

  Note that the air supply pipe 34 is not limited to the above-described configuration. FIG. 5 is a schematic longitudinal sectional view of a ship showing a modification of the air supply pipe in the ship friction reducing device of the first embodiment.

  As shown in FIG. 5, the air supply pipe 51 is arranged inside the hull 10, one end 51a is connected to the air supply device 32, and the other end is branched into four branch pipes 51b and 51c. One branch pipe 51b is connected to each end portion in the longitudinal direction (ship width direction Y) of the passage member 41, and two branch pipes 51c are connected to an intermediate portion of the passage member 41 in the longitudinal direction (ship width direction Y). Has been. In this case, it is desirable that the connection positions of the branch pipes 51b and 51c and the passage member 41 are equally spaced. Therefore, the amount of compressed air blown out into the water from each air outlet 44 in the passage member 41 can be made uniform.

  Further, the passage member 41 is not limited to the configuration described above. FIG. 6 is a cross-sectional view illustrating a modification of the air blowing portion in the ship friction reducing device of the first embodiment.

  As shown in FIG. 6, the air blowing part 35 is provided along the ship width direction Y on the flat outer surface part of the ship bottom 13 as an air passage of the present invention. The air blowing portion 35 is a passage member 61 having a semi-oval shape (or semi-elliptical shape) whose cross-sectional shape along the ship length direction X is long in the ship length direction X. The passage member 61 has a flat shape, the amount of downward projection from the outer surface portion of the ship bottom outer plate 27 is suppressed, the end in the ship length direction X contacts the outer surface portion of the ship bottom outer plate 27, and is welded. By being fixed by the above, a sealed passage 62 is secured. The air supply pipe 34 is fixed by welding with the end of the branch pipe 34 b fitted into the through hole 43. The passage member 61 is provided with a plurality of air outlets 63 at predetermined intervals in the longitudinal direction. The plurality of air outlets 63 are provided on the stern 12 side of the passage member 61 along the outer surface portion of the bottom shell outer plate 27, and thus face the outer surface portion side of the bottom shell plate 27 on the stern 12 side from the passage member 61. Open.

  As described above, in the ship friction reducing device of the first embodiment, the air supply device 32 provided inside the hull 10 and the air blowing portion 35 provided along the ship width direction outside the ship bottom 13. A passage member (air passage) 41, a plurality of air outlets 44 provided at predetermined intervals in the longitudinal direction of the passage member 41, an air supply pipe 34 connecting the air supply device 32 and the passage member 41 in the ship, and Is provided.

  Therefore, the air from the air supply device 32 is supplied to the passage 42 of the passage member 41 provided outside the ship bottom 13 through the air supply pipe 34 disposed in the ship, and blown out into the water from the plurality of air outlets 44. Thus, the surface of the ship bottom 13 can be covered with bubbles to reduce the frictional resistance. At this time, since the passage member 41 is provided outside the ship bottom 13, there is no need to provide a gas chamber or the like in the ship, and the number of structural members arranged in the ship can be reduced and the degree of design freedom can be improved. There is no need to provide a large number of air outlets on the bottom 13, and the strength of the bottom 13 can be prevented from lowering.

  In the ship friction reducing device of the first embodiment, the other end of the air supply pipe 34 branches into a plurality of branch pipes 34 b and is connected to both longitudinal ends of the passage member 41. Therefore, the air branches from the air supply pipe 34 and is supplied to both ends of the passage member 41, reducing the supply pressure difference in the longitudinal direction of the passage member 41, and blown out into the water from the plurality of air outlets 44. The air amount can be made uniform.

  In the ship friction reducing device of the first embodiment, the passage member 41 is provided on the flat outer surface portion of the ship bottom 13. Therefore, air is blown out into the water from the plurality of air outlets 44 toward the flat outer surface portion of the ship bottom 13, and the air is appropriately diffused into the flat outer surface portion of the ship bottom 13 to efficiently reduce the frictional resistance. Can do.

  In the ship friction reducing device of the first embodiment, the other end of the air supply pipe 34 passes through the through hole 43 of the ship bottom outer plate 27 and is connected to the passage 42 of the passage member 41. Therefore, the connection configuration between the air supply pipe 34 and the passage member 41 can be simplified, the sealing performance at the connection portion can be easily ensured, and the water tightness can be improved.

  In the ship friction reducing device according to the first embodiment, the air supply pipe 34 has an outer diameter dimension set to be smaller than a width dimension in the ship length direction of the passage member 41. Accordingly, when air is supplied from the air supply pipe 34 to the passage 42 of the passage member 41, the flow passage area is increased, so that the air can be easily diffused in the passage member 41, and a plurality of air outlets are provided. The amount of air blown out into the water from 44 can be made uniform.

  In the ship friction reducing device of the first embodiment, the cross-sectional shape of the passage member 41 along the ship length direction X is a semicircular shape. Therefore, existing piping or the like can be processed and used as the passage member 41, and an increase in manufacturing cost can be suppressed.

  In the ship friction reducing device of the first embodiment, the cross-sectional shape of the passage member 61 along the ship length direction X is a semi-oval or semi-elliptical shape that is long in the ship length direction X. Therefore, the amount of protrusion from the ship bottom 13 can be reduced to suppress an increase in navigation resistance.

  In the ship friction reducing device of the first embodiment, a plurality of air outlets 44 are provided on the stern 12 side of the passage member 41. Accordingly, air is blown out from the air outlet 44 into the water on the stern 12 side, and the bubbles can be appropriately diffused along the outer surface portion of the bottom 13.

  In the ship friction reducing device of the first embodiment, the plurality of air outlets 44 are configured such that the opening area increases as the distance from the connection portion of the air supply pipe 34 in the passage member 41 increases. Therefore, the air supplied from the air supply pipe 34 to the passage member 41 has a high pressure in the vicinity of the connecting portion, but is difficult to go out into the water in the vicinity of the connecting portion, and easily out into the water at a position away from the connecting portion. The amount of air blown out into the water from the plurality of air outlets 44 can be made uniform.

[Second Embodiment]
FIG. 7 is a longitudinal sectional view of a ship equipped with the ship friction reducing device of the second embodiment. In addition, the same code | symbol is attached | subjected to the member which has the same function as embodiment mentioned above, and detailed description is abbreviate | omitted.

  In the second embodiment, as shown in FIG. 7, the air supply pipe 52 is disposed inside the hull 10, one end is connected to the air supply device 32, and the other end is the longitudinal direction of the passage member 41 (the ship It is connected to the middle part in the width direction Y). Therefore, the air supply pipe 52 is simplified.

  Note that the air supply pipe 52 is not limited to the above-described configuration. FIG. 8 is a longitudinal sectional view of a ship showing a modification of the ship friction reducing device of the second embodiment.

  In the modification of the second embodiment, as shown in FIG. 8, the air supply pipe 53 is disposed inside the hull 10, one end is connected to the air supply device 32, and the other end is the longitudinal length of the passage member 41. It is connected to one end of the direction (ship width direction Y). Therefore, the air supply pipe 53 is simplified.

  As described above, in the ship friction reducing device of the second embodiment, the air supply pipes 52 and 53 are arranged in the ship, one end is connected to the air supply device 32, and the other end is the longitudinal length of the passage member 41. Connected to the end or middle of the direction. Therefore, by connecting the air supply device 32 in the ship and the passage member 41 outside the ship bottom 13 by the air supply pipes 52 and 53 in the ship, the arrangement length of the air supply pipes 52 and 53 is minimized. The structural member arrange | positioned to can be reduced.

[Third Embodiment]
FIG. 9 is a longitudinal sectional view of a ship equipped with the ship friction reducing device of the third embodiment, and FIG. 10 is a system diagram showing an air supply path. In addition, the same code | symbol is attached | subjected to the member which has the same function as embodiment mentioned above, and detailed description is abbreviate | omitted.

  In the third embodiment, as shown in FIG. 9, the air supply pipe 54 is disposed inside the hull 10, one end 54 a is connected to the air supply device 32, and the other end is six branch pipes 54 b, Branches to 54c and 54d. The air blowing part 35 is provided in the flat outer surface part of the ship bottom 13 along the ship width direction Y as an air passage of the present invention. The air blowing portions 35 are passage members 55a, 55b, and 55c that are provided in a plurality (three in this embodiment) with a predetermined interval in the ship width direction Y. Each passage member 55a, 55b, 55c is provided with a plurality of air outlets 56a, 56b, 56c at predetermined intervals in the longitudinal direction. In the air supply pipe 54, two branch pipes 54b are connected to respective end portions in the longitudinal direction (ship width direction Y) of the passage member 55a, and two branch pipes 54c are each end portion in the longitudinal direction of the passage member 55b. And two branch pipes 54d are connected to the ends of the passage member 55c in the longitudinal direction.

  Further, as shown in FIG. 10, in the air supply pipe 54, flow control valves 57a, 57b, and 57c are provided in the branch pipes 54b, 54c, and 54d, respectively. Therefore, by adjusting the opening degree of the flow rate adjusting valves 57a, 57b, and 57c, the amount of air blown from the air blowing ports 56a, 56b, and 56c in the passage members 55a, 55b, and 55c can be adjusted.

  As described above, in the ship friction reducing device according to the third embodiment, a plurality of passage members 55a, 55b, and 55c are provided outside the ship bottom 13 at predetermined intervals in the ship width direction Y. Each branch pipe 54b, 54c, 54d is connected to each passage member 55a, 55b, 55c. Accordingly, air is supplied from the air supply pipe 54 to the passage members 55a, 55b, 55c through the branch pipes 54b, 54c, 54d, and a plurality of air outlets in the ship width direction Y of the ship bottom 13 are provided. The amount of air blown out from the water 56a, 56b, 56c can be made uniform.

  In the ship friction reducing device of the third embodiment, the flow rate adjusting valves 57a, 57b, and 57c are provided in the branch pipes 54b, 54c, and 54d of the air supply pipe 54, respectively. Therefore, by adjusting the amount of air supplied to the passage members 55a, 55b, and 55c by the flow rate adjusting valves 57a, 57b, and 57c, the optimum air blowing amount is set according to the hull shape and the navigational state of the ship. Can do.

10 Hull 11 Bow 12 Stern 13 Bottom 14 Port side (ship side)
15 Starboard (ship side)
21 Air supply equipment room 27 Ship bottom skin 28, 29 Ship side skin 31 Friction reduction device 32 Air supply device 33 Air suction port 34, 51, 52, 53, 54 Air supply piping 35, 36 Air blowing portion 41, 61 Passage member (Air passage)
42, 62 Passage 44, 63, 56a, 56b, 56c Air outlet 57a, 57b, 57c Flow control valve X Ship length direction Y Ship width direction Z Ship height direction

Claims (12)

An air supply device provided inside the hull;
An air passage provided along the ship width direction on the outside of the ship bottom;
A plurality of air outlets provided at predetermined intervals in the longitudinal direction of the air passage;
An air supply pipe connecting the air supply device and the air passage in a ship;
A ship friction reducing device characterized by comprising:   The said air supply piping is arrange | positioned in a ship, One end part is connected to the said air supply apparatus, The other end part is connected to the edge part or intermediate part of the longitudinal direction in the said air path at least. The ship friction reducing device according to claim 1.   3. The ship friction reducing device according to claim 1, wherein the air supply pipe has a second end branched into a plurality of ends and is connected to at least both ends in the longitudinal direction of the air passage.   A plurality of the air passages are provided outside the ship bottom at a predetermined interval in the width direction of the ship, and the other end of the air supply pipe branches into a plurality and is connected to the plurality of air passages. The ship friction reducing device according to any one of claims 1 to 3.   5. The ship friction reducing device according to claim 4, wherein a flow rate adjusting valve is provided in a branch pipe in which the other end portion of the air supply pipe branches in a plurality.   The ship's friction reducing device according to any one of claims 1 to 5, wherein the air passage is provided in a flat outer surface portion of a ship bottom.   7. The ship friction reducing device according to claim 1, wherein the other end of the air supply pipe passes through a ship bottom outer plate and is connected to the air passage. 8.   The friction reduction of the ship according to any one of claims 1 to 7, wherein the air supply pipe is set to have an outer diameter dimension smaller than a width dimension in a ship length direction of the air passage. apparatus.   The ship air friction reducing device according to any one of claims 1 to 8, wherein the air passage has a semicircular cross-sectional shape along a ship length direction.   9. The ship's friction reduction according to claim 1, wherein the air passage has a semi-oval shape or a semi-elliptical shape whose cross-sectional shape along the ship length direction is long in the ship length direction. apparatus.   11. The ship friction reducing device according to claim 1, wherein the plurality of air outlets are provided on a stern side of the air passage.   The ship according to any one of claims 1 to 11, wherein an opening area of the plurality of air outlets increases as the distance from the connection portion of the air supply pipe in the air passage increases. Friction reduction device.

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