WO2018142825A1

WO2018142825A1 - Friction reducing device for ship

Info

Publication number: WO2018142825A1
Application number: PCT/JP2017/047059
Authority: WO
Inventors: 真一 ▲高▼野
Original assignee: 三菱重工業株式会社
Priority date: 2017-01-31
Filing date: 2017-12-27
Publication date: 2018-08-09
Also published as: JP6655563B2; KR20190009347A; JP2018122717A; KR102258219B1

Abstract

This friction reducing device for ships is provided with: a gas chamber (41) provided inside a hull (10); a ship bottom shell plate (27) that partitions the inside of the gas chamber (41) and the outside of the hull (10); a plurality of air blowout ports (42) provided in the ship bottom shell plate (27); a compressor (43); a sub air supply piping (46) in which the area of a passage which connects the compressor (43) and the gas chamber (41) and communicates with the gas chamber (41) is set smaller than the opening area of the air blowout ports (42); a container (64) that covers and partitions the air blowout ports (42) inside the gas chamber (41); and a plurality of through holes (67) provided in a predetermined position of the container (64), wherein the predetermined position does not face a connection path (46a) to the gas chamber (41) of a sub air supply piping (46).

Description

Ship friction reduction device

The present invention relates to a ship friction reducing device that reduces frictional resistance acting on the 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 out into the water and the surface of the hull is covered with bubbles. In this hull frictional resistance reduction device, a gas supply pipe is connected to a gas chamber (air chamber), and a plurality of air jets are provided on the outer plate of the ship bottom in the gas chamber. A baffle plate is disposed between the air outlet and each air outlet. Therefore, the air supplied from the gas supply pipe to the gas chamber collides with the baffle plate and is diffused, and is ejected from each air ejection port into the water in a substantially uniform state. As such a hull frictional resistance reduction device, for example, there is one described in Patent Documents 1-3 below.

JP 2008-143345 A JP 2010-120609 A Japanese Patent Laying-Open No. 2015-081043

In the conventional frictional resistance reduction type ship described above, the blower provided in the ship is driven, the air sucked from the outside is supplied to the gas chamber from the gas supply pipe, and the air diffused by colliding with the baffle plate is supplied to each air. It is ejected from the spout into the water in an almost uniform state. In this case, a plurality of gas chambers are provided at predetermined positions on the ship bottom, and it is necessary to dispose a plurality of gas supply pipes from the blower to each gas chamber. However, since there are many structures and partitions in the ship, the space for disposing the gas supply pipe is limited. In view of this, it is conceivable to use a compressor instead of the blower and reduce the diameter of the gas supply pipe, thereby reducing the size of the gas supply pipe and reducing the installation space. However, if the pipe diameter of the gas supply pipe is reduced using a compressor, the flow velocity of the air supplied from the gas supply pipe to the gas chamber increases, and the air colliding with the baffle plate may be uniformly diffused into the gas chamber. It becomes difficult. Then, the pressure distribution of the air in the gas chamber becomes non-uniform, and the amount of air ejected from each air ejection port into the water varies, making it difficult to sufficiently reduce the frictional resistance of the hull.

This invention solves the subject mentioned above, and aims at providing the friction reduction apparatus of the ship which aims at the simplification of a structure and the improvement of a frictional resistance reduction effect.

A ship friction reducing device of the present invention for achieving the above object is provided in a gas chamber provided inside a hull, a partition wall partitioning the gas chamber from the outside of the hull, and the partition wall. A plurality of air outlets, a compressor, an air supply passage in which a passage area connecting the compressor and the gas chamber and communicating with the gas chamber is set to an area smaller than an opening area of the air outlet; A container that covers and divides the air outlet in the gas chamber, and a plurality of through holes provided at predetermined positions of the container that do not oppose the connection portion of the air supply passage to the gas chamber. It is characterized by.

Therefore, the compressed air generated by the compressor is supplied to the gas chamber through the air supply passage, and at this time, the compressed air supplied to the gas chamber is uniformly dispersed in the gas chamber by colliding with the container. It enters the container through the through hole, and blows out into the water outside the hull through each air outlet. At this time, the flow area of the compressed air supplied from the air supply passage to the gas chamber and the flow rate per unit time are set so that the passage area to the gas chamber in the air supply passage is smaller than the opening area of the air outlet. Therefore, the frictional resistance reduction effect can be improved by uniformizing the amount of air blown from each air outlet and covering the surface of the hull with air bubbles. Further, by reducing the diameter of the air supply passage, the structure can be simplified and the arrangement space can be reduced.

In the ship friction reducing device of the present invention, the plurality of air outlets are provided along the width direction of the hull, and a plurality of the through holes are provided corresponding to one air outlet, The passage area of the air supply passage is set to an area smaller than the opening area of one air outlet.

Therefore, the flow area of the compressed air supplied from the air supply passage to the gas chamber and the flow rate per unit time are specified by setting the passage area of the air supply passage to be smaller than the opening area of one air outlet. As a result, the amount of air ejected from each air outlet can be made uniform.

In the ship friction reducing device of the present invention, one of the through holes has a passage area set to an area smaller than an opening area of one of the air outlets.

Accordingly, the air that is supplied from the air supply passage to the gas chamber and collides with the cover plate, and the diffused air is blown into the water from each air outlet that is larger than the passage area of the air supply passage. The amount of air ejected from the air can be made uniform.

In the ship friction reducing device according to the present invention, the container includes a collision plate disposed at a position facing the connection portion of the air supply passage to the gas chamber, and a partition connecting the collision plate and the partition wall. And the through hole is formed in the partition plate.

Therefore, the container is constituted by the collision plate and the partition plate, and the through hole is formed in the partition plate, so that the compressed air supplied from the air supply passage to the gas chamber collides with the collision plate, so that the air is Can then be uniformly dispersed, and then enter the container uniformly through each through hole, and the amount of air blown out into the water outside the hull through each air outlet can be made uniform. it can.

In the ship friction reducing device according to the present invention, the gas chamber includes a ceiling portion that faces the partition wall, and a sidewall portion that connects the partition wall and the ceiling portion, and the sidewall portion and the partition plate. A predetermined gap is provided between the two.

Therefore, the air that is supplied to the gas chamber and collides with the collision plate enters the container through the through hole through the predetermined gap, and the air is uniformly dispersed in the container, and from each air outlet to the outside of the hull. Can be ejected uniformly into the water.

The ship friction reducing device of the present invention is characterized in that the through hole is provided close to the partition wall side.

Therefore, by providing the through hole close to the partition wall side, the water accumulated between the gas chamber and the container is guided from the through hole into the container during the maintenance of the hull, and easily drained to the outside from the air outlet. can do.

In the ship friction reducing device of the present invention, the plurality of air outlets are provided along a width direction of the hull, and the container covers the plurality of air outlets.

Therefore, since the container covers the plurality of air outlets, the structure of the container can be simplified.

In the ship friction reducing device of the present invention, the container is composed of one collision plate and two partition plates, each end in the longitudinal direction is connected to a side wall of the gas chamber, and the partition plate is A predetermined gap is provided between the side wall portion that is not connected and the two partition plates.

Therefore, the container is composed of a collision plate and a partition plate, and by connecting each end in the longitudinal direction to the side wall of the gas chamber, a sealed space can be easily secured in the container with a simple configuration, The structure can be simplified and the cost can be reduced.

In the friction reducing device for a ship according to the present invention, the container is provided with a partition plate that divides the container for each air outlet.

Therefore, by partitioning the inside of the container for each air outlet by the partition plate, the amount of air blown out from each air outlet can be made uniform.

In the ship friction reducing device of the present invention, the plurality of air outlets are provided along the width direction of the hull, and the plurality of containers are provided so as to cover the plurality of air outlets, A plurality of through holes are provided in the plurality of containers.

Therefore, since the container covers each air outlet, the amount of air blown out from each air outlet can be made uniform.

In the ship friction reducing device of the present invention, a plurality of the through holes are provided in the container, and a detachable plug is attached to at least one of the through holes.

Therefore, by attaching a plug to one of the plurality of through holes provided in the container, when the through hole in use is blocked by marine organisms, the plug can be removed and another through hole can be used. By doing so, the apparatus can be used for a long time.

In the ship friction reducing device of the present invention, the air supply passage is branched from a midway portion to be provided with a main passage and a sub-passage, and the main passage and the sub-passage are respectively connected to the gas chamber, An on-off valve is provided.

Therefore, when the main passage and the sub-passage are provided as the air supply passage, the main passage is opened by the on-off valve and the sub-passage is closed, and the main passage in use is blocked by marine organisms, the on-off valve By opening the sub passage and making it usable, the apparatus can be used for a long period of time.

In the ship friction reducing device of the present invention, the compressor is capable of supplying compressed air of 500 kPa or more to the gas chamber.

Therefore, by reducing the diameter of the air supply passage, the structure can be simplified and the installation space can be reduced.

According to the ship friction reducing device of the present invention, the structure can be simplified and the frictional resistance reducing effect can be improved.

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 diagram showing an air supply system. FIG. 4 is a perspective view schematically showing the gas chamber. FIG. 5 is a longitudinal sectional view showing the gas chamber. 6 is a cross-sectional view taken along the line VI-VI in FIG. 7 is a sectional view taken along line VII-VII in FIG. FIG. 8 is an exploded view showing the gas chamber. FIG. 9 is a longitudinal sectional view showing a gas chamber in the ship friction reducing device of the second embodiment. FIG. 10 is a perspective view schematically showing a gas chamber in the ship friction reducing device of the third embodiment. FIG. 11 is a longitudinal sectional view showing the gas chamber. FIG. 12 is a longitudinal sectional view showing a gas chamber in the ship friction reducing device of the fourth embodiment. FIG. 13 is a longitudinal sectional view showing the operation of the gas chamber. FIG. 14 is a longitudinal sectional view showing a gas chamber in the ship friction reducing device of the fifth embodiment. FIG. 15 is a perspective view schematically showing a gas chamber in the ship friction reducing apparatus of the sixth embodiment. FIG. 16 is a longitudinal sectional view showing a gas chamber. 17 is a cross-sectional view taken along the line XVII-XVII in FIG. FIG. 18 is an exploded view showing a gas chamber. FIG. 19 is a longitudinal sectional view showing a gas chamber in the ship friction reducing device of the seventh embodiment. FIG. 20 is a cross-sectional view of a ship equipped with the ship friction reducing device of the eighth embodiment. FIG. 21 is a longitudinal sectional view showing a gas chamber.

Hereinafter, a preferred embodiment of a ship friction reducing device according to the present invention will be described 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, FIG. 2 is a schematic bottom view of the ship equipped with the ship friction reducing device, and FIG. 3 represents an air supply system. FIG.

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.

The hull 10 has an engine room 17 defined 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 reduction device 31 includes an air supply device 32, an air cooler 33, a ventilation cylinder 34, an air suction port 35, an air blowing portion 36, an air blowing portion 37, a seawater intake portion 38, and a pump 39. is doing. The air blowing portions 36 are disposed on the port 14 (ship side skin 28) and the starboard 15 (ship side skin 29). The air blowing part 37 and the seawater intake part 38 are arranged on the ship bottom 13 (the ship bottom outer plate 27) on the bow 11 side. The air supply device 32 and the air cooler 33 are installed in the air supply device chamber 21. The ventilation tube 34 and the air suction port 35 are disposed in the deck exposure unit 25. The ventilation tube 34 communicates with the air supply device chamber 21 and is used to ventilate the air supply device chamber 21. The air suction port 35 is connected to the air supply device 32. The air supply device 32 is connected to the

air blowing portions

36 and 37 via the air cooler 33. The seawater intake unit 38 is connected to the air cooler 33 via the pump 39.

The seawater intake part 38 and the air blowing part 37 are, for example, arranged on the center line CL of the hull 10 and are arranged on the flat part of the ship bottom skin 27 on the ship bottom 13. The seawater intake unit 38 is disposed closer to the bow 11 than the air blowing unit 37. The air blowing portions 36 are disposed on the ship side skins 28 and 29 of the port 14 and starboard 15 on the bow 11 side. Each air blowing portion 36 is arranged symmetrically with respect to the center line CL, and is arranged obliquely so that the bow 11 side approaches. The seawater intake part 38 is disposed between the air blowing parts 36 provided in both the

cages

14 and 15.

The air supply device 32 pressurizes the air sucked from the air suction port 35 and supplies the pressurized compressed air from the air cooler 33 to the

air blowing portions

36 and 37. The pump 39 supplies seawater taken from the seawater intake unit 38 to the air cooler 33. The air cooler 33 cools the compressed air using seawater. The air cooler 33 is a heat exchanger that exchanges heat between compressed air and seawater, for example. The air cooler 33 may be configured to cool the compressed air by spraying seawater into the compressed air, or may be configured to cool the compressed air by blowing the compressed air into the seawater. The

air blowing portions

36 and 37 blow out the compressed air supplied from the air supply device 32 into the water. That is, air is blown out into the water from the

air blowing portions

36 and 37 of the hull 10, and bubbles formed by the blown air are sent out to the flat portion of the bottom 13, and the hull 10 is covered by the bubbles, thereby the hull. Ten frictional resistances are reduced.

Further, as shown in FIG. 3, the air blowing portion 37 disposed on the ship bottom 13 on the bow 11 side includes a plurality of gas chambers 41 provided inside the hull 10, and the inside of each gas chamber 41 and the outside of the hull 10. And a plurality of air outlets 42 provided on the ship bottom outer plate 27. The gas chamber 41 is a sealed space, and an air supply device 32 is connected via an air cooler 33. The plurality of air outlets 42 are passages that penetrate from the gas chamber 41 through the ship bottom outer plate 27 to the outside of the hull 10, that is, in water. The plurality of air outlets 42 are arranged along the ship length direction (X direction) of the ship bottom 13 and at predetermined intervals in the ship width direction (Y direction). Therefore, the compressed air blown out into the water from the plurality of air outlets 42 becomes bubbles, and flows rearward through the flat portion of the ship bottom 13 and diffuses in the width direction.

The air supply device 32 includes a gas chamber 41, an air outlet 42, a compressor 43, a main air supply pipe 44, a main chamber 45, and a plurality of sub air supply pipes (air supply passages) 46. ing. The compressor 43 is connected to an air suction port 35 via an air intake pipe 47. The compressor 43 is connected to a main chamber 45 via a main air supply pipe 44. For example, the compressor 43 can pressurize the taken-in air to 500 kPa or more (desirably, 700 kPa to 1300 kPa). The main air supply pipe 44 is provided with an on-off valve 48, a flow meter 49, and a pressure gauge 50.

The main chamber 45 can store a predetermined amount of compressed air supplied under pressure by the compressor 43 at a predetermined pressure. The main chamber 45 is connected to the downstream end of the main air supply pipe 44 and to the other upstream end of each of the plurality of sub air supply pipes 46. Each sub air supply pipe 46 has a downstream end connected to the gas chamber 41. The auxiliary air supply pipe 46 is provided with a flow rate adjustment valve 51 and a shutoff valve 52.

Therefore, when the on-off valve 48 is opened and the compressor 43 is driven, the compressor 43 pressurizes the taken-in air to a predetermined pressure and sends it to the main chamber 45 through the main air supply pipe 44. The main chamber 45 is compressed air. Is stored at a predetermined pressure. Here, when the flow regulating valve 51 and the shutoff valve 52 are opened, the compressed air in the main chamber 45 is supplied to each gas chamber 41 via each sub air supply pipe 46, and the compressed air supplied to each gas chamber 41. Are blown out into the water from a plurality of air outlets 42 and flow into the rear of the hull 10 along the flat portion of the bottom 13 as bubbles.

Here, the gas chamber 41 of the first embodiment will be described in detail. 4 is a perspective view schematically showing the gas chamber, FIG. 5 is a longitudinal sectional view showing the gas chamber, FIG. 6 is a sectional view taken along the line VI-VI in FIG. 5, and FIG. 7 is a sectional view taken along the line VII-VII in FIG. Sectional drawing and FIG. 8 are exploded views showing a gas chamber.

As shown in FIGS. 4 to 7, the gas chamber 41 includes a ceiling portion 61, a pair of first side wall portions 62, and a pair of second side wall portions 63, and together with the ship bottom skin 27 (the ship bottom 13). An air supply space S1 having a box-shaped sealed shape is formed. The ceiling portion 61 is arranged in parallel to the ship bottom outer plate 27 (the ship bottom 13), and is a rectangular plate shape that is long along the series direction of a plurality (five in the present embodiment) of the air outlets 42. I am doing. The pair of first side wall parts 62 are arranged so as to be parallel to each other and orthogonal to the ship bottom outer plate 27, and have a long rectangular flat plate shape along the series direction of the air outlets 42. The pair of second side wall parts 63 are arranged so as to be parallel to each other and perpendicular to the ship bottom outer plate 27 and have a long rectangular flat plate shape along the direction perpendicular to the series direction of the air outlets 42. ing. And a pair of 1st side wall part 62 and a pair of 2nd side wall part 63 comprise the frame which makes | forms a rectangular shape, and each

side wall part

62 and 63 has connected the ship bottom outer plate 27 and the ceiling part 61. FIG.

The gas chamber 41 is connected to the ceiling 61 at the tip of the auxiliary air supply pipe 46 of the air supply device 32. The sub air supply pipe 46 is set in the ceiling portion 61 at a position where the connecting portion 46 a faces the air outlet 42 at the center of the five air outlets 42.

The gas chamber 41 is provided with a container 64 that covers each air outlet 42 and divides the air chamber 41 from the air supply space S1. The container 64 includes a collision plate 65 and a pair of partition plates 66, and has an air circulation space S 2 that forms a box-shaped hermetic shape together with the ship's bottom outer plate 27 (the ship's bottom 13) and each second side wall 63 of the gas chamber 41. Forming. The collision plate 65 is disposed between the ship bottom outer plate 27 (the ship bottom 13) and the ceiling portion 61 and in parallel with and opposed to both, and is a rectangular flat plate that is long along the series direction of the air outlets 42. It has a shape. The pair of partition plates 66 are arranged so as to be parallel to each other, orthogonal to the ship bottom outer plate 27 and parallel to the first side wall 62, and are long along the series direction of the air outlets 42. It has a rectangular flat plate shape. The collision plate 65 and each partition plate 66 constitute a C-shaped cover, and the longitudinal ends of the collision plate 65 and each partition plate 66 are connected to the respective second side wall portions 63, and the lower ends of the partition plates 66. The portion is connected to the ship bottom skin 27.

In the container 64, the collision plate 65 is arranged with a predetermined interval from the ceiling portion 61 of the gas chamber 41, and each partition plate 66 is arranged with a predetermined interval from the first side wall portion 62 of the gas chamber 41. In the container 64, the connection portion 46 a of the auxiliary air supply pipe 46 is disposed so as to face the collision plate 65.

Further, the container 64 is provided with a through hole 67 at a predetermined position where the connecting portion 46a of the sub air supply pipe 46 does not face. A plurality of the through holes 67 are formed in the pair of partition plates 66. Each through hole 67 is provided in each partition plate 66 in the same number as each air outlet 42, and is provided on both sides of each air outlet 42. Therefore, the auxiliary air supply pipe 46 is arranged along the ship height direction Z, each through hole 67 is formed along the ship length direction X, and each air outlet 42 is arranged along the ship height direction Z. The Rukoto.

And in this embodiment, the passage area of the connection part 46a where the sub air supply piping 46 communicates with the gas chamber 41 (air supply space S1) is set to an area smaller than the opening area of each air outlet 42. . Specifically, a plurality of air outlets 42 are provided along the ship width direction Y, and a plurality of through holes 67 correspond to one air outlet 42 (two in this embodiment). The passage area of the connecting portion 46 a in the auxiliary air supply pipe 46 is set to an area smaller than the opening area of one air outlet 42. Further, one through hole 67 has a passage area set to an area smaller than the opening area of one air outlet 42.

In addition, each air blowing port 42 is a perfect circle shape, is all the same shape, and is set to the same opening area. However, the shape of the air outlet 42 is not limited to a perfect circle shape, and may be an elliptical shape, an oval shape, an oval shape, a rounded square shape, a square shape, a rhombus shape, a triangular shape, or the like. Each through-hole 67 is also a perfect circle, and all have the same shape and the same opening area. However, the shape of the through hole 67 is not limited to a perfect circle, and may be other shapes.

The air outlets 42 and the through holes 67 have the same shape, the same opening area, and the same passage area. However, for example, the shape is changed, and the air blowing positions far from the connecting portion 46a of the sub air supply pipe 46 are used. The opening area of the opening 42 and the passage area of each through hole 67 may be increased. In this case, the passage area of the connection portion 46 a in the sub air supply pipe 46 is set to an area smaller than the opening area of the largest air outlet 42. Further, the passage area of the largest through hole 67 is set to be smaller than the opening area of the largest air outlet 42.

In addition, although two through holes 67 are provided for one air outlet 42, the number and formation position thereof are not limited to those described above.

The auxiliary air supply pipe 46 has a connection portion 46 a connected to the ceiling portion 61 of the gas chamber 41, and the passage area of the connection portion 46 a is set to an area smaller than the opening area of the air outlet 42. In this case, the auxiliary air supply pipe 46 has substantially the same diameter at any position in the longitudinal direction, and the connection portion 46a is directly connected to the ceiling portion 61, but is not limited to this configuration. For example, a configuration in which a large-diameter portion is provided between the connection portion 46a of the auxiliary air supply pipe 46 and the gas chamber 41 may be used. Even in this configuration, the passage area of the connection portion 46a connected to the large-diameter portion is small. An area smaller than the opening area of the air outlet 42 is set.

By the way, as shown in FIG. 8, the gas chamber 41 and the container 64 are configured to be disassembled in consideration of maintainability. In the gas chamber 41, the ceiling portion 61 has a plurality of attachment holes 71 formed in the outer peripheral portion, and a plurality of attachment holes 73 formed in the flange portions 72 of the

side wall portions

62 and 63. Then, in a state where the ceiling portion 61 is placed on the flange portion 72 of each

side wall portion

62, 63, the bolt 74 passes through each mounting

hole

71, 73 and is screwed into the nut 75, so that the ceiling portion 61 is Fastened to the

side wall portions

62 and 63. Similarly, in the container 64, the collision plate 65 has a plurality of attachment holes 76 formed in the outer peripheral portion, and a plurality of attachment holes 78 formed in the flange portion 77 of each partition plate 66. Then, in a state where the collision plate 65 is placed on the flange portion 77 of each partition plate 66, the bolt 79 passes through each mounting

hole

76, 78 and is screwed into the nut 80, so that the collision plate 65 is engaged with each partition plate 66. It is concluded to. A seal member may be interposed between the ceiling portion 61 and the

side wall portions

62 and 63 and between the collision plate 65 and each partition plate 66.

Therefore, in the gas chamber 41, as shown in FIGS. 3 to 7, the compressed air pressurized by the compressor 43 (see FIG. 3) is supplied to the air supply space S1 of the gas chamber 41 through the auxiliary air supply pipe 46. The Here, the compressed air supplied to the air supply space S 1 flows in a direction that changes in the horizontal radial direction in the gas chamber 41 by colliding with the collision plate 65 of the container 64. Are dispersed almost uniformly. The compressed air dispersed almost uniformly in the gas chamber 41 flows into the gap between the first side wall 62 and the partition plate 66 and enters the air circulation space S 2 in the container 64 through each through hole 67. Then, the compressed air that has entered the air circulation space S 2 is blown out into the water outside the ship bottom outer plate 27 through each air outlet 42.

As described above, in the ship friction reducing device according to the first embodiment, the gas chamber 41 provided inside the hull 10, the ship bottom skin plate 27 that partitions the inside of the gas chamber 41 and the outside of the hull 10, and the ship bottom A plurality of air outlets 42 provided in the outer plate 27, a compressor 43, a passage area connecting the compressor 43 and the gas chamber 41 and communicating with the gas chamber 41 is smaller than the opening area of the air outlet 42 Of the sub-air supply pipe 46 set to the above, a container 64 that covers and partitions the air outlet 42 in the gas chamber 41, and a container 64 that does not face the connection portion 46 a of the sub-air supply pipe 46 to the gas chamber 41. A plurality of through holes 67 provided at predetermined positions are provided.

Therefore, the passage area to the gas chamber 41 in the sub air supply pipe 46 is set to an area smaller than the opening area of one air outlet 42, so that the compression supplied from the sub air supply pipe 46 to the gas chamber 41 is performed. The air flow rate and the flow rate per unit time will be defined, and the amount of air jetted from each air outlet 42 will be made uniform, and the surface of the hull will be properly covered with bubbles to improve the frictional resistance reduction effect. Can do.

That is, by using the compressor 43 as an air supply source, the compressed air obtained by pressurizing the air is supplied to the gas chamber 41, so that the auxiliary air supply pipe 46 can be reduced in diameter. If the diameter of the auxiliary air supply pipe 46 can be reduced, the workability of the auxiliary air supply pipe 46 can be improved and the routing property in the hull 10 can be improved. As a result, the manufacturability is improved, the structure can be simplified, and the arrangement space in the hull 10 can be reduced.

In the ship friction reducing device of the first embodiment, the passage area of one through hole 67 is set to be smaller than the opening area of one air outlet 42. Accordingly, the amount of air that enters the container 64 from the gas chamber 41 through the through hole 67 is limited, and variation in the pressure of the air in the gas chamber 41 is reduced, so that the air outlet 42 can be moved from the container 64. The amount of air passing through can be made uniform.

In the ship friction reducing device of the first embodiment, as the container 64, a collision plate 65 disposed at a position facing the connection portion 46a to the gas chamber 41 of the auxiliary air supply pipe 46, the collision plate 65, and the ship bottom outer plate. 27, and a through hole 67 is formed in the partition plate 66. Therefore, the compressed air supplied from the auxiliary air supply pipe 46 to the gas chamber 41 collides with the collision plate 65, so that the air can be uniformly dispersed in the gas chamber 41. 64, the amount of air blown out into the water through each air outlet 42 can be made uniform.

In the ship friction reducing device according to the first embodiment, as the gas chamber, a ceiling portion 61 that opposes the ship bottom outer plate 27 and a plurality of

side wall portions

62 and 63 that connect the ship bottom outer plate 27 and the ceiling portion 61 are provided. A predetermined gap is provided between the first side wall portion 62 and the partition plate 66. Therefore, the air that has been supplied to the gas chamber 41 and collided with the collision plate 65 goes around the predetermined gap and enters the container 64 from each through hole 67, and the air is uniformly dispersed in the container 64. The air can be uniformly ejected from the air outlet 42 into the water.

In the ship friction reducing device of the first embodiment, a plurality of air outlets 42 are provided along the ship width direction Y, and the container 64 covers the plurality of air outlets 42. Therefore, the structure of the container 64 can be simplified.

In the ship friction reducing device according to the first embodiment, the container 64 includes one collision plate 65 and two partition plates 66, and each end in the longitudinal direction is connected to the second side wall 63 of the gas chamber 41. In addition, a predetermined gap is provided between the first side wall portion 62 to which the partition plate 66 is not connected and the two partition plates 66. Therefore, the air circulation space S2 sealed in the container 64 can be easily secured with a simple configuration, and the structure can be simplified and the cost can be reduced.

In the ship friction reducing device of the first embodiment, the compressor 43 can supply compressed air of 500 kPa or more to the gas chamber 41. Therefore, the structure of the sub air supply pipe 46 can be simplified and the arrangement space can be reduced.

[Second Embodiment]
FIG. 9 is a longitudinal sectional view showing a gas chamber in 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 ship friction reducing device of the second embodiment, as shown in FIG. 9, the gas chamber 41 includes a ceiling part 61, a pair of first side wall parts 62, and a pair of second side wall parts 63, An air supply space S1 having a box-shaped sealed shape is formed together with the ship bottom outer plate 27 (the ship bottom 13). The gas chamber 41 is connected to the ceiling 61 at the tip of the sub air supply pipe 46 of the air supply device 32.

The gas chamber 41 is provided with a container 64 that covers each air outlet 42 and divides the air chamber 41 from the air supply space S1. The container 64 includes a collision plate 65 and a pair of partition plates 66, and has an air circulation space S 2 that forms a box-shaped hermetic shape together with the ship's bottom outer plate 27 (the ship's bottom 13) and each second side wall 63 of the gas chamber 41. Forming. The container 64 is provided with a through hole 67 at a predetermined position where the connecting portion 46a of the auxiliary air supply pipe 46 does not face. A plurality of the through holes 67 are formed in the pair of partition plates 66 in the vicinity of the ship bottom outer plate 27 side. That is, the through hole 67 is provided below the intermediate position of the partition plate 66 in the height direction of the hull 10. In this case, the through hole 67 may be provided as a notch at the lowest end position of the partition plate 66 in the height direction of the hull 10.

Therefore, the compressed air pressurized by the compressor 43 (see FIG. 3) is supplied to the air supply space S 1 of the gas chamber 41 through the sub air supply pipe 46. Here, the compressed air supplied to the air supply space S 1 flows in a direction that changes in the horizontal radial direction in the gas chamber 41 by colliding with the collision plate 65 of the container 64. Are dispersed almost uniformly. The compressed air dispersed almost uniformly in the gas chamber 41 flows into the gap between the first side wall 62 and the partition plate 66 and enters the air circulation space S 2 in the container 64 through each through hole 67. Then, the compressed air that has entered the air circulation space S 2 is blown out into the water outside the ship bottom outer plate 27 through each air outlet 42.

By the way, since the gas chamber 41 is located below the full load water line WL, when air is not blown into the water from the air outlet 42, seawater enters the container 64 from the air outlet 42, and the through hole 67 enters the gas chamber 41 and the gas chamber 41 and the container 64 are filled with seawater. In this state, when compressed air is supplied to the gas chamber 41 through the sub air supply pipe 46, enters the container 64 through each through hole 67, and is blown into the water through each air outlet 42, Seawater in the chamber 41 and the container 64 is pushed out into the water from the air outlet 42 by air. At this time, since the through hole 67 is formed close to the ship bottom outer plate 27 side, seawater is prevented from remaining in the gap between the first side wall portion 62 and the partition plate 66.

As described above, in the ship friction reducing device of the second embodiment, the through hole 67 is provided close to the ship bottom outer plate 27 side of the partition plate 66. That is, the through hole 67 is provided below the intermediate position of the partition plate 66 in the height direction of the hull 10.

Accordingly, when air is not blown into the water from the air outlet 42, seawater enters the gas chamber 41 and the container 64 from the air outlet 42, but the through-hole 67 is formed close to the ship bottom outer plate 27 side. Therefore, when the hull is lifted to the land during the maintenance of the hull 10, the seawater in the gas chamber 41 and the container 64 is drained to the outside from the air outlet 42 and remains in the gap between the first side wall 62 and the partition plate 66. There is little to do. As a result, the maintainability of the gas chamber 41 and the container 64 can be improved.

[Third Embodiment]
FIG. 10 is a perspective view schematically showing a gas chamber in the ship friction reducing device of the third embodiment, and FIG. 11 is a longitudinal sectional view showing the gas chamber. 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 ship friction reducing device of the third embodiment, as shown in FIGS. 10 and 11, the gas chamber 41 includes a ceiling portion 61, a pair of first side wall portions 62, and a pair of second side wall portions 63. The air supply space S1 which is configured and forms a box-shaped hermetic shape together with the ship bottom outer plate 27 (the ship bottom 13) is formed. The gas chamber 41 is connected to the ceiling 61 at the tip of the sub air supply pipe 46 of the air supply device 32.

The gas chamber 41 is provided with a container 64A that covers each air outlet 42 inside. The container 64 A includes a collision plate 65 and a pair of partition plates 66, and forms a box-shaped sealed space together with the ship bottom outer plate 27 (the ship bottom 13) and the second side wall portions 63 of the gas chamber 41. Yes. The container 64 A is provided with a plurality of partition plates 81 that divide the internal space for each air outlet 42. Therefore, the container 64A forms a plurality of air circulation spaces S21, S22, S23, S24, and S25 having a box-shaped sealed shape by the partition plates 81. The container 64A is provided with a plurality of through holes 67 at predetermined positions where the connecting portions 46a of the auxiliary air supply pipe 46 do not face each other. That is, each through hole 67 is formed corresponding to each air circulation space S21, S22, S23, S24, S25 in each partition plate 66.

For this reason, the compressed air supplied to the air supply space S1 of the gas chamber 41 through the sub air supply pipe 46 collides with the collision plate 65 of the container 64A, so that the direction of the compressed air is changed along the horizontal radiation direction in the gas chamber 41. The flow is changed and is dispersed almost uniformly in the gas chamber 41. The compressed air dispersed almost uniformly in the gas chamber 41 enters the air circulation spaces S21, S22, S23, S24, and S25 in the container 64A through the through holes 67. The compressed air that has entered the air circulation spaces S21, S22, S23, S24, and S25 is blown out into the water outside the ship bottom outer plate 27 through the air blowing ports 42.

As described above, in the ship friction reducing device of the third embodiment, the container 64A is provided with the partition plate 81 that is partitioned for each air outlet 42 inside.

Therefore, the container 64A is blown into the water from each air outlet 42 by partitioning into a plurality of air circulation spaces S21, S22, S23, S24, and S25 corresponding to each air outlet 42 by each partition plate 81. The amount of air ejection can be made uniform.

[Fourth Embodiment]
FIG. 12 is a longitudinal sectional view showing a gas chamber in the ship friction reducing device of the fourth embodiment, and FIG. 13 is a longitudinal sectional view showing the action of the gas chamber. 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 ship friction reducing device of the fourth embodiment, as shown in FIG. 12, the gas chamber 41 is provided with a container 64 that covers each air outlet 42 and divides it from the air supply space S1. The container 64 includes a collision plate 65 and a pair of partition plates 66, and has an air circulation space S 2 that forms a box-shaped hermetic shape together with the ship's bottom outer plate 27 (the ship's bottom 13) and each second side wall 63 of the gas chamber 41. Forming. The container 64 is provided with a plurality of through holes 67 in a predetermined position where the connecting portion 46 a of the auxiliary air supply pipe 46 does not face, that is, in each partition plate 66. The plurality of through-holes 67 are each provided with a detachable plug 91 in a through-hole 67 less than half of the through-hole 67. The plug 91 is mounted from the outside of the partition plate 66, that is, from the gas chamber 41 side (air supply space S1 side).

Therefore, a plurality of through holes 67 that are not equipped with the plug 91 can be used. In the plurality of through holes 67, not only air flows but also seawater flows when the friction reducing device is not used. Then, marine organisms may adhere and block the through hole 67. Moreover, since seawater adheres to the partition plate 66, rust may occur. If foreign matter such as marine organisms or rust adheres to the partition plate 66, the foreign matter may block the through hole 67. When maintenance of the hull 10 finds that the through hole 67 is blocked by a foreign object, as shown in FIG. 13, the closed through hole 67 is closed by a plug 92, and plugs 91 (see FIG. 12) are plugged from the plurality of through holes 67. It can be removed and used. The plug 92 is mounted from the inside of the partition plate 66, that is, from the inside of the container 64 (air circulation space S23 side). In this case, the plug 91 may be removed from the plurality of through holes 67 and the closed through hole 67 may not be closed by the plug 92.

Thus, in the ship friction reducing device of the fourth embodiment, a detachable plug 91 is attached to at least one through hole 67 among the plurality of through holes 67 provided in the container 64. Therefore, when the through-hole 67 in use is blocked by foreign matter such as marine organisms, the plug 91 can be removed from the other through-hole 67 and used, so that the device can be used for a long period of time.

[Fifth Embodiment]
FIG. 14 is a longitudinal sectional view showing a gas chamber in the ship friction reducing device of the fifth 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 ship friction reducing device of the fifth embodiment, as shown in FIG. 14, the gas chamber 41 includes a ceiling portion 61, a pair of first side wall portions 62, and a pair of second side wall portions 63. An air supply space S1 having a box-shaped sealed shape is formed together with the ship bottom outer plate 27 (the ship bottom 13). The gas chamber 41 is connected to the ceiling 61 at the tip of the sub air supply pipe 46 of the air supply device 32. The gas chamber 41 is provided with a container 64 that covers each air outlet 42 and divides the air chamber 41 from the air supply space S1. The container 64 includes a collision plate 65 and a pair of partition plates 66, and has an air circulation space S 2 that forms a box-shaped hermetic shape together with the ship's bottom outer plate 27 (the ship's bottom 13) and each second side wall 63 of the gas chamber 41. Forming. The container 64 is provided with a through hole 67 at a predetermined position where the connecting portion 46a of the auxiliary air supply pipe 46 does not face.

The sub air supply pipe 46 is branched from the middle portion, and is provided with a sub air supply pipe 46 as a main passage and a sub passage 53. The auxiliary air supply pipe 46 and the auxiliary passage 53 are connected to the gas chamber 41 and provided with on-off

valves

54 and 55, respectively.

Therefore, the secondary air supply pipe 46 can be used with the open / close valve 54 opened, and the secondary passage 53 cannot be used because the open / close valve 55 is closed. The auxiliary air supply pipe 46 not only allows air to flow, but also allows seawater to flow in when the friction reducing device is not used. Then, marine organisms may adhere and block the auxiliary air supply pipe 46. Further, since seawater adheres to the auxiliary air supply pipe 46, rust may be generated. If foreign matter such as marine organisms or rust adheres to the auxiliary air supply pipe 46, the foreign matter may block the passage. If the auxiliary air supply pipe 46 is blocked by foreign matter during maintenance of the hull 10, the on / off valve 54 of the auxiliary air supply pipe 46 is closed to disable the use, and the on / off valve 55 of the auxiliary passage 53 is opened to be used. To do.

As described above, in the ship friction reducing device according to the fifth embodiment, the auxiliary air supply pipe 46 and the auxiliary passage 53 are provided as a main passage branched from the middle portion of the auxiliary air supply pipe 46, and the auxiliary air supply pipe is provided. 46 and the sub-passage 53 are connected to the gas chamber 41, and on-off

valves

54 and 55 are provided, respectively. Therefore, when the sub air supply pipe 46 in use is blocked by foreign matter such as marine organisms, the on / off valve 54 of the sub air supply pipe 46 is closed to disable use, and the on / off valve 55 of the sub passage 53 is opened for use. By making it possible, the device can be used over a long period of time.

[Sixth Embodiment]
15 is a perspective view schematically showing a gas chamber in the ship friction reducing device of the sixth embodiment, FIG. 16 is a longitudinal sectional view showing the gas chamber, and FIG. 17 is a sectional view taken along XVII-XVII in FIG. FIG. 18 is an exploded view showing a gas chamber. 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 ship friction reducing device of the sixth embodiment, as shown in FIGS. 15 to 17, the gas chamber 41 includes a ceiling portion 61, a pair of first side wall portions 62, and a pair of second side wall portions 63. The air supply space S1 which is configured and forms a box-shaped sealed shape together with the ship bottom skin 27 (the ship bottom 13) is formed. The gas chamber 41 is connected to the ceiling 61 at the tip of the sub air supply pipe 46 of the air supply device 32. The sub air supply pipe 46 is set in the ceiling portion 61 at a position where the connecting portion 46 a faces the air outlet 42 at the center of the five air outlets 42.

The gas chamber 41 is provided with a plurality of containers 101 that cover the air outlets 42 and partition from the air supply space S1. A plurality (five in this embodiment) of air outlets 42 are provided along the ship width direction Y, and a plurality of containers 101 are provided so as to cover each air outlet 42.

Each container 101 includes a collision plate 102 and a partition cylinder 103, and forms an air circulation space S2 having a box-shaped sealed shape together with a ship bottom outer plate 27 (ship bottom 13). The collision plate 102 is disposed between the ship bottom outer plate 27 (the ship bottom 13) and the ceiling portion 61 and in parallel with and opposed to both, and has a disk shape facing one air outlet 42. ing. The partition cylinder 103 has a cylindrical shape and is orthogonal to the ship bottom skin 27 and is disposed around each air outlet 42. The collision plate 102 and each partition tube 103 constitute a hollow cylinder having one side open, and the end of the open side partition tube 103 is connected to the ship bottom outer plate 27.

Each container 101 covers a plurality of air outlets 42 so that the containers 101 are arranged at a predetermined interval. In each container 101, the collision plate 102 is arranged with a predetermined distance from the ceiling 61 of the gas chamber 41, and each partition tube 103 is spaced from the

side walls

62 and 63 of the gas chamber 41 with a predetermined distance. Has been placed. And each container 101 is arrange | positioned at linear form, and the connection part 46a of the subair supply piping 46 is arrange | positioned facing the collision plate 102 of the container 101 of the intermediate part.

Further, each container 101 is provided with a through hole 104 at a predetermined position where the connecting portion 46a of the sub air supply pipe 46 does not face. A plurality of (four in this embodiment) through holes 104 are formed in each partition tube 103 at equal intervals in the circumferential direction. Therefore, the auxiliary air supply pipe 46 is disposed along the ship height direction Z, and each through hole 104 is formed along a direction (the ship length direction X and the ship width direction Y) orthogonal to the ship height direction Z. The air outlets 42 are arranged along the ship height direction Z.

And in this embodiment, the passage area of the connection part 46a where the sub air supply piping 46 communicates with the gas chamber 41 (air supply space S1) is set to an area smaller than the opening area of each air outlet 42. . Specifically, a plurality of air outlets 42 are provided along the ship width direction Y, each container 101 is provided for one air outlet 42, and four for each container 101. The through holes 104 are provided, and the passage area of the connecting portion 46 a in the sub air supply pipe 46 is set to be smaller than the opening area of one air outlet 42.

Further, one through hole 104 has a passage area set to an area smaller than the opening area of one air outlet 42.

In addition, each through-hole 104 is a perfect circle shape, is all the same shape, and is set to the same passage area. However, the shape of the through hole 104 is not limited to a perfect circle shape, and may be an elliptical shape or a polygonal shape. In addition, one container 101 is provided for one air outlet 42, and four through holes 104 are provided in one container 101. However, the number and formation positions are limited to those described above. It is not something.

By the way, as shown in FIG. 18, the gas chamber 41 and the container 101 are configured to be disassembled in consideration of maintainability. In the container 101, the collision plate 102 has a plurality of attachment holes 111 formed in the outer peripheral portion, and a plurality of attachment holes 113 formed in the flange portion 112 of each partition tube 103. Then, in a state where the collision plate 102 is placed on the flange portion 112 of each partition tube 103, the bolt 114 passes through each

attachment hole

111, 113 and is screwed into the nut 115, so that the collision plate 102 is Fastened to the tube 103.

Therefore, in the gas chamber 41, the compressed air pressurized by the compressor 43 (see FIG. 3) is supplied to the air supply space S1 of the gas chamber 41 through the sub air supply pipe 46. Here, the compressed air supplied to the air supply space S 1 flows in a direction that changes in the horizontal radial direction in the gas chamber 41 by colliding with the collision plate 102 of the container 101. Are dispersed almost uniformly. The compressed air dispersed almost uniformly in the gas chamber 41 flows into the gaps between the

side wall portions

62 and 63 and the partition cylinders 103 and enters the air circulation space S2 in the containers 101 through the through holes 104. To do. Then, the compressed air that has entered the air circulation space S 2 is blown out into the water outside the ship bottom outer plate 27 through each air outlet 42.

As described above, in the ship friction reducing device of the sixth embodiment, the gas chamber 41 provided inside the hull 10, the ship bottom outer plate 27 that partitions the inside of the gas chamber 41 and the outside of the hull 10, and the ship bottom A plurality of air outlets 42 provided in the outer plate 27, a compressor 43, a passage area connecting the compressor 43 and the gas chamber 41 and communicating with the gas chamber 41 is smaller than the opening area of the air outlet 42 Of the sub-air supply pipe 46 set to 1), the container 101 that covers and partitions the air outlet 42 in the gas chamber 41, and the container 101 that does not face the connection portion 46a of the sub-air supply pipe 46 to the gas chamber 41. A plurality of through holes 104 provided at predetermined positions are provided.

In the ship friction reducing device of the sixth embodiment, a plurality of air outlets 42 are provided along the ship width direction Y, a plurality of containers 101 are provided so as to cover each air outlet 42, and a plurality of each container 101 is provided. Through-holes 104 are provided. Accordingly, the amount of air blown out from each air outlet 42 into the water can be made uniform.

[Seventh Embodiment]
FIG. 19 is a longitudinal sectional view showing a gas chamber in the ship friction reducing device of the seventh 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 ship friction reducing device of the seventh embodiment, as shown in FIG. 19, the gas chamber 41 includes a ceiling part 61, a pair of first side wall parts 62, and a pair of second side wall parts 63, An air supply space S1 having a box-shaped sealed shape is formed together with the ship bottom outer plate 27 (the ship bottom 13). The gas chamber 41 is connected to the ceiling 61 at the tip of the sub air supply pipe 46 of the air supply device 32. The sub air supply pipe 46 is set in the ceiling portion 61 at a position where the connecting portion 46 a faces the air outlet 42 at the center of the five air outlets 42.

The gas chamber 41 is provided with a plurality of containers 101 that cover the air outlets 42 and partition from the air supply space S1. A plurality (five in this embodiment) of air outlets 42 are provided along the ship width direction Y, and a plurality of containers 101 are provided so as to cover each air outlet 42. Each container 101 is constituted by a collision plate 102 and a partition cylinder 103, and forms an air circulation space S2 having a box-shaped hermetic shape together with a ship bottom outer plate 27 (ship bottom 13). Each container 101 covers a plurality of air outlets 42 so that the containers 101 are arranged at a predetermined interval. In addition, the container 101 is provided with a through hole 104 at a predetermined position where the connecting portion 46a of the auxiliary air supply pipe 46 does not face. A plurality of (four in this embodiment) through holes 104 are formed in each partition tube 103 at equal intervals in the circumferential direction. A plurality of through-holes 104 are formed in the partition cylinder 103 in the vicinity of the ship bottom outer plate 27 side. That is, the through hole 104 is provided below the intermediate position of the partition tube 103 in the height direction of the hull 10. In this case, the through hole 104 may be provided as a notch at the lowest position in the height direction of the hull 10 in the partition tube 103.

Note that the operation of this embodiment is substantially the same as that of the sixth embodiment and the second embodiment, and thus the description thereof is omitted.

Thus, in the ship friction reducing device of the seventh embodiment, the through hole 104 is provided close to the ship bottom skin 27 side of the partition tube 103. That is, the through hole 104 is provided below the intermediate position of the partition tube 103 in the height direction of the hull 10.

Accordingly, when air is not blown into the water from the air outlet 42, seawater enters the gas chamber 41 and the container 101 from the air outlet 42, but the through hole 104 is formed close to the ship bottom outer plate 27 side. Therefore, when the hull 10 is pulled up to the ground during the maintenance of the hull 10, the seawater in the gas chamber 41 and the container 101 is drained to the outside from the air outlet 42, and in the gap between the first side wall 62 and the partition cylinder 103. There is almost no residue. As a result, the maintainability of the gas chamber 41 and the container 101 can be improved.

[Eighth Embodiment]
FIG. 20 is a cross-sectional view of a ship equipped with the ship friction reducing device of the eighth embodiment, and FIG. 21 is a vertical cross-sectional view showing a gas chamber. 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 eighth embodiment, as shown in FIG. 20, the hull 10 is provided with a friction reducing device 31, and the friction reducing device 31 includes an air supply device 32, an air suction port 35, and an air blowing portion 36. And have. The air blowing portion 36 is disposed on the inclined ship bottom 13 (the ship bottom outer plate 27) on the bow 11 side.

The air supply device 32 includes a gas chamber 41, an air outlet 42, a compressor 43 (see FIG. 3), and a plurality of sub air supply pipes 46. The compressor 43 is connected to the air suction port 35 and to the gas chamber 41 via a plurality of sub air supply pipes 46. The gas chamber 41 is a flooded portion of the hull 10 and is provided in a portion where the width of the hull 10 changes when the position of the hull 10 in the height direction changes due to a change in the width of the hull 10. Therefore, this gas chamber 41 is provided in the inclined part of the ship bottom 13 (ship bottom outer plate 27) of the hull 10.

In the ship friction reducing device of the eighth embodiment, as shown in FIG. 21, the gas chamber 41 includes a ceiling part 61, a pair of first side wall parts 62, and a pair of second side wall parts 63, An air supply space S1 having a box-shaped sealed shape is formed together with the inclined ship bottom outer plate 27 (the ship bottom 13). The gas chamber 41 is connected to the ceiling 61 at the tip of the sub air supply pipe 46 of the air supply device 32.

The gas chamber 41 is provided with a container 64 that covers each air outlet 42 inside. The container 64 includes a collision plate 65 and a pair of partition plates 66, and forms a box-shaped sealed space together with the inclined ship bottom outer plate 27 (ship bottom 13) and each second side wall portion 63 of the gas chamber 41. is doing. In addition, the container 64 is provided with a plurality of partition plates 81 that divide the internal space for each air outlet 42 inside. Therefore, the container 64 forms a plurality of air circulation spaces S21, S22, S23, S24, and S25 having a box-shaped sealed shape by the partition plates 81. The container 64 is provided with a plurality of through

holes

67a, 67b, 67c, 67d, 67e at predetermined positions where the connecting portion 46a of the auxiliary air supply pipe 46 does not face. That is, the through

holes

67a, 67b, 67c, 67d, 67e are formed corresponding to the air circulation spaces S21, S22, S23, S24, S25 in the partition plates 66, respectively.

The passage areas of the through

holes

67a, 67b, 67c, 67d, and 67e of the containers 64 are different. Specifically, the passage area of the through hole 67e of the container 64 corresponding to the air outlet 42 at the high position of the hull 10 is the same as that of the through hole 67a of the container 64 corresponding to the air outlet 42 at the low position of the hull 10. It is set to be smaller than the passage area. Therefore, the flow rate of air flowing into the air circulation spaces S21, S22, S23, S24, and S25 from the air supply space S1 through the through

holes

67a, 67b, 67c, 67d, and 67e is a container corresponding to the through hole 67e at a high position. 64 is smaller than the container 64 corresponding to the through hole 67a in the lower position. That is, the plurality of containers 64 reduce the flow rate of air guided to the corresponding air outlets 42 as the through

holes

67a, 67b, 67c, 67d, and 67e corresponding to the containers 64 are located at higher positions. Then, the through

holes

67 a, 67 b, 67 c, 67 d, 67 e of the plurality of containers 64 have a function of adjusting the flow rate of the air guided to the air outlet 42 corresponding to the container 64.

Therefore, the compressed air pressurized by the compressor 43 (see FIG. 3) is supplied to the air supply space S 1 of the gas chamber 41 through the sub air supply pipe 46. Here, the compressed air supplied to the air supply space S 1 flows in a direction that changes in the horizontal radial direction in the gas chamber 41 by colliding with the collision plate 65 of the container 64. Are dispersed almost uniformly. The compressed air dispersed almost uniformly in the gas chamber 41 flows into the gap between the first side wall portion 62 and the partition plate 66, and the air in the container 64 passes through the through

holes

67a, 67b, 67c, 67d, 67e. It enters into the distribution spaces S21, S22, S23, S24, S25. Then, the compressed air that has entered the air circulation spaces S21, S22, S23, S24, and S25 is blown out into the water outside the ship bottom outer plate 27 (the ship bottom 13) through each air outlet 42.

At this time, the higher the air outlet 42 is, the smaller the flow rate of air guided to the air outlet 42 becomes. On the other hand, the lower the air outlet 42 is, the higher the water pressure is applied to the air outlet 42 from the outside of the hull 10, and the resistance of water to the air blown out from the air outlet 42 into the water increases. As a result, the flow rate of the air blown out from the plurality of air outlets 42 having different heights is equalized.

As described above, in the friction reduction device according to the eighth embodiment, the gas chamber 41 provided inside the hull 10, the ship bottom skin 27 that partitions the gas chamber 41 from the outside of the hull 10, and the ship bottom skin 27, a plurality of air outlets 42, a compressor 43, a secondary air supply pipe 46 connecting the compressor 43 and the gas chamber 41, and the air outlet 42 are covered and partitioned in the gas chamber 41. The container 64, a plurality of partition plates 81 that divide the interior of the container 64 for each air outlet 42, and a plurality of containers 64 provided at predetermined positions of the container 64 that do not face the connection portion 46 a to the gas chamber 41 of the sub air supply pipe 46. Through

holes

67 a, 67 b, 67 c, 67 d, 67 e, and the passage area of the through hole 67 e of the container 64 corresponding to the air outlet 42 at the high position of the hull 10 is set to the air outlet at the low position of the hull 10. It is set to be smaller than the passage area of the through hole 67a of the container 64 corresponding to the mouth 42.

Accordingly, the flow rate of the air blown from the plurality of air blowing ports 42 is equalized, and the diffusibility of the air blown from the plurality of air blowing ports 42 is also equalized, so that the air along the outer wall of the ship Can be made uniform.

In each embodiment described above, the gas chamber 41 having a square box shape and the container 64 having a square box shape or the container 101 having a cylindrical shape have been described. It is not limited to the shape of 101, and may be set as appropriate according to the arrangement location in the hull 10 and the like.

10 Hull 11 Bow 12 Stern 13 Bottom 14 Port side (ship side)
15 Starboard (ship side)
DESCRIPTION OF SYMBOLS 21 Air supply equipment room 27

Ship bottom skin

28, 29 Ship side skin 31 Friction reduction device 32 Air supply device 33 Air cooler 34 Ventilation pipe 35

Air suction port

36, 37 Air blowing part 38 Seawater intake part 39 Pump 41 Gas chamber 42 Air blowing Port 43 Compressor 44 Main air supply pipe 45 Main chamber 46 Sub air supply pipe (air supply passage)
61 Ceiling part 62 First side wall part 63 Second

side wall part

64, 101

Container

65, 102 Collision plate 66

Partition plate

67, 67a, 67b, 67c, 67d, 67e, 104 Through hole 103 Partition cylinder (partition plate)
S1 Air supply space S2, S21, S22, S23, S24, S25 Air circulation space X Captain direction Y Ship width direction Z Ship height direction

Claims

A gas chamber provided inside the hull;
A partition wall that partitions the gas chamber and the outside of the hull;
A plurality of air outlets provided in the partition wall;
A compressor,
An air supply passage in which a passage area connecting the compressor and the gas chamber and communicating with the gas chamber is set to an area smaller than an opening area of the air outlet;
A container that covers and partitions the air outlet in the gas chamber;
A plurality of through holes provided at predetermined positions of the container that do not oppose the connection portion of the air supply passage to the gas chamber;
A ship friction reducing device characterized by comprising:
The plurality of air outlets are provided along the width direction of the hull, a plurality of the through holes are provided corresponding to one air outlet, and the area of the air supply passage is 1 2. The ship friction reducing device according to claim 1, wherein the area is set to an area smaller than an opening area of each of the air outlets.
3. The ship friction reducing device according to claim 2, wherein the one through hole has a passage area smaller than an opening area of the one air outlet.
The container includes a collision plate disposed at a position facing a connection portion of the air supply passage to the gas chamber, and a partition plate that connects the collision plate and the partition wall, The ship friction reducing device according to any one of claims 1 to 3, wherein the friction reducing device is formed on the partition plate.
The gas chamber has a ceiling portion facing the partition wall and a side wall portion connecting the partition wall and the ceiling portion, and a predetermined gap is provided between the side wall portion and the partition plate. The ship friction reducing device according to claim 4, wherein:
6. The ship friction reducing device according to any one of claims 1 to 5, wherein the through hole is provided close to the partition wall side.
The plurality of air outlets are provided along a width direction of the hull, and the container covers the plurality of air outlets. The ship friction reducing apparatus as described.
The container is composed of one collision plate and two partition plates, each end portion in the longitudinal direction is connected to a side wall portion of the gas chamber, the side wall portion to which the partition plate is not connected, and the two The ship friction reducing device according to claim 7, wherein a predetermined gap is provided between the partition plates.
9. The ship friction reducing device according to claim 8, wherein the container is provided with a partition plate inside the container for each air outlet.
The plurality of air outlets are provided along the width direction of the hull, the plurality of containers are provided so as to cover each of the plurality of air outlets, and the plurality of through holes are provided in the plurality of containers. The ship friction reducing device according to any one of claims 1 to 7, wherein the ship friction reducing device is provided.
11. The ship friction according to claim 1, wherein a plurality of the through holes are provided in the container, and a detachable plug is attached to at least one of the through holes. Reduction device.
The air supply passage is branched from an intermediate portion to be provided with a main passage and a sub-passage, and the main passage and the sub-passage are respectively connected to the gas chamber and provided with an on-off valve. The ship friction reducing device according to any one of claims 1 to 11.
The ship's friction reduction device according to any one of claims 1 to 12, wherein the compressor is capable of supplying compressed air of 500 kPa or more to the gas chamber.