Vessel

Abstract

To provide a vessel for effectively reducing friction between a hull and water.SOLUTION: A vessel 10 includes a hull 20 and a gas supply device 40 for supplying gas to a bottom 25 of the hull. A plurality of cavities 30 to which the gas is supplied is provided on the bottom. The cavities are separated from each other in the width direction. Each of the cavities extends in a longitudinal direction.SELECTED DRAWING: Figure 1

Description

Technical Field

[0001] The present invention relates to a ship.

Background Art

[0002] Patent Document 1 proposes a friction reduction device that reduces the friction between the hull of a ship and water. The friction reduction device of Patent Document 1 ejects gas from a group of air ejection holes provided on the bottom of the ship. By forming a film of bubbles on the bottom of the ship with the ejected gas, the friction between the hull and water can be reduced. By reducing the friction, the fuel efficiency can be improved and the environmental load can be reduced.

Prior Art Documents

Patent Documents

[0003]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0004] In the ship disclosed in Patent Document 1, the formation position of the group of air ejection holes is devised for the purpose of ejecting gas in a wide area of the bottom of the ship. On the other hand, no improvement is made to the bottom of the ship. Therefore, the ejected gas immediately rises from the bottom of the ship to the water surface, and the friction cannot be effectively reduced.

[0005] The present invention has been made in consideration of the above points, and an object thereof is to provide a ship capable of effectively reducing the friction between the hull and water.

Means for Solving the Problems

[0006] The ship according to the present embodiment includes: a hull, a gas supply device that supplies gas to the bottom of the hull, and is provided with a plurality of depressions to which the gas is supplied on the bottom of the hull. The plurality of depressions are spaced apart from each other in the width direction, and each of the plurality of depressions extends in the front-rear direction.

Advantages of the Invention

[0007] According to the present invention, the friction between the hull and water can be effectively reduced.

Brief Description of the Drawings

[0008]

Figure 1

Figure 2

Figure 3

Figure 4

Figure 5

Figure 6

Figure 7

Figure 8

Figure 9

Figure 10

Embodiments for Carrying Out the Invention

[0009] One embodiment of the present disclosure relates to the following <1> to <12>.

[0010] <1> A hull, A gas supply device that supplies gas to the bottom of the hull, A plurality of depressions for supplying the gas are provided on the bottom of the hull, The plurality of depressions are spaced apart from each other in the width direction, Each of the plurality of depressions extends in the longitudinal direction, a ship.

[0011] <2> Some of the plurality of depressions are provided on one side in the width direction of the bottom of the hull, The remainder of the plurality of depressions are provided on the other side in the width direction of the bottom of the hull, the ship according to <1>.

[0012] <3> The gas supply device includes a gas supply source that supplies the gas, and a gas supply cylinder portion that supplies the gas supplied from the gas supply source toward the depression, The gas supply cylinder portion extends out of the hull to the outside of the ship, the ship according to <1> or <2>.

[0013] <4> The gas supply cylinder portion includes a discharge end portion that opens toward the rear side in the longitudinal direction, the ship according to <3>.

[0014] <5> The gas supply device includes a gas supply source that supplies the gas, and a gas supply cylinder portion that supplies the gas supplied from the gas supply source toward the depression, The gas supply cylinder portion includes a discharge end portion that opens toward the rear side in the longitudinal direction, the ship according to any one of <1> to <4>.

[0015] <6> The gas supply device includes a gas supply source that supplies the gas, and a gas supply cylinder portion that supplies the gas supplied from the gas supply source toward the depression, The gas supply cylinder part includes a plurality of branch cylinder parts, Each of the plurality of branch cylinder parts supplies the gas to another depression included in the plurality of depressions. The ship according to any one of <1> to <5>.

[0016] <7> The plurality of depressions are symmetrically arranged around a plane extending in the vertical direction through the center in the width direction. The ship according to any one of <1> to <6>.

[0017] <8> The hull includes a screw, The screw is not located on the extension line of each of the plurality of depressions. The ship according to claim 1 of any one of <1> to <7>.

[0018] <9> One or more depressions included in the plurality of depressions bend outward in the width direction on the rear side in the front-rear direction. The ship according to any one of <1> to <8>.

[0019] <10> One or more depressions included in the plurality of depressions bend upward in the vertical direction on the rear side in the front-rear direction. The ship according to any one of <1> to <9>.

[0020] <11> The bottom of the ship includes a low-inclination part in a cross section orthogonal to the front-rear direction, where the angle formed with the width direction is 30° or less, One or more depressions included in the plurality of depressions are provided on the low-inclination part of the bottom of the ship. The ship according to any one of <1> to <10>.

[0021] <12> One or more depressions included in the plurality of depressions do not include an acute-angled or right-angled corner in a cross section orthogonal to the front-rear direction. The ship according to any one of <1> to <11>.

[0022] Hereinafter, an embodiment of the present disclosure will be described with reference to the drawings. In the drawings attached to this specification, for the convenience of easy understanding, the scale, the aspect ratio of the vertical and horizontal dimensions, etc. are appropriately changed and exaggerated from those of the actual object. In some of the drawings, the configurations etc. shown in some of the drawings may be omitted in other drawings. The scale and the aspect ratio of the vertical and horizontal dimensions etc. may be different between the drawings.

[0023] In this specification, terms for specifying shapes, geometric conditions, and their degrees, such as the term "orthogonal" and the values of lengths and angles, etc., are not limited to a strict meaning, and are interpreted to include a range that can be expected to have a similar function.

[0024] To clarify the relationship of directions between the drawings, in some of the drawings, the common front-rear direction D1, width direction D2, and vertical direction D3 are shown by arrows with common reference signs. The tip side of the arrow is the first side of each direction. The side opposite to the tip of the arrow is the second side of each direction. An arrow pointing forward from the paper surface along the direction perpendicular to the paper surface of the drawing is shown by a symbol with a dot in a circle, as shown in FIG. 2 for example. An arrow pointing backward from the paper surface along the direction perpendicular to the paper surface of the drawing is shown by a symbol with an "x" in a circle, as shown in FIG. 4 for example.

[0025] FIGS. 1 to 10 are diagrams for explaining an embodiment. FIG. 1 is a perspective view schematically showing a specific example of the ship 10. FIG. 2 is a view showing the ship 10 shown in FIG. 1 from the front side in the front-rear direction D1. FIG. 3 is a view showing the ship 10 shown in FIG. 1 from the outside in the width direction D2. FIG. 4 is a view showing the ship 10 shown in FIG. 1 from the lower side in the vertical direction D3.

[0026] In this specification, unless otherwise specified, the terms "front", "rear", "upper", "lower", "longitudinal direction", "width direction", and "vertical direction" with respect to the ship 10 and its components refer to "front", "rear", "upper", "lower", "longitudinal direction", "width direction", and "vertical direction" based on the floating posture in water. The "longitudinal direction" is the traveling direction when the ship is moving straight forward. The "front" is the "front" when the ship is moving straight forward. The "vertical direction" is the vertical direction of the ship 10 floating in water. The "width direction" is the direction orthogonal to both the "longitudinal direction" and the "vertical direction".

[0027] As shown in FIGS. 1 to 4, the ship 10 includes a hull 20 and a gas supply device 40. The hull 20 is formed of wood or metal. The hull 20 can generate buoyancy and float in water. The water in which the ship 10 floats may be seawater or freshwater. In FIG. 3, the water surface WL is shown together with the ship 10.

[0028] The hull 20 may be configured in the same manner as a known ship. As shown in FIGS. 3 and 4, the hull 20 may include a main body 21, a rudder 22 and a screw 23 held by the main body 21. The hull 20 is not particularly limited. The hull 20 may be a small ship, a medium-sized ship, or a large ship. The hull 20 may be a fishing boat, a merchant ship such as a passenger ship or a cargo ship, a work ship, or a warship such as an aircraft carrier or an Aegis ship.

[0029] As shown in FIGS. 1 to 4, the hull 20 includes a bottom 25. The bottom 25 is the part located in water when the ship 10 is floating in water. As shown in FIGS. 1 to 5, a plurality of depressions 30 are provided on the bottom 25. The depression 30 is a recessed part on the outer surface of the bottom 25. That is, the depression 30 is a recess provided on the outer surface of the bottom 25. FIG. 5 shows an enlarged view of one depression 30 of the hull 20 shown in FIG. 1 from the rear side in the longitudinal direction D1.

[0030] The gas supply device 40 supplies gas to the bottom 25 of the hull 20. The gas supply device 40 supplies gas into the depression 30. The gas supply device 40 may supply gas to the front side region located in the front - rear direction D1 of the depression 30. The gas may be air. The gas may be one or more of nitrogen, oxygen, and carbon dioxide.

[0031] As shown in FIG. 3, the gas supply device 40 may include a gas supply source 45 and a gas supply cylinder portion 50. In the illustrated example, the gas supply source 45 supplies gas. The gas supply cylinder portion 50 forms a gas flow path. As shown in FIG. 3, the gas supply source 45 is connected to the gas supply cylinder portion 50. The gas supply source 45 supplies gas to the gas supply cylinder portion 50. The gas supply cylinder portion 50 discharges the gas supplied from the gas supply source 45 toward the depression 30.

[0032] The gas supply source 45 may be a known device capable of supplying gas. The gas supply source 45 may be a blower that blows out gas. The gas supply source 45 may include an electric motor and a blower. The gas supply source 45 may include an electric motor and a compressor. The blower and the compressor are driven by an electric motor to suck gas and discharge the sucked gas.

[0033] As shown in FIG. 2, the gas supply source 45 may be disposed on the front side in the front - rear direction D1 within the main body 21 of the hull 20. By shortening the distance from the gas supply source 45 to the front side region in the front - rear direction D1 of the depression 30, the pressure loss within the gas supply cylinder portion 50 can be reduced.

[0034] The gas supply cylinder portion 50 may be constituted by a pipe 52 made of metal or resin. The gas supply cylinder portion 50 guides the gas from the gas supply source 45 to the depression 30. The gas supply cylinder portion 50 may discharge gas to the front side region located in the front - rear direction D1 of the depression 30. According to this example, the moving distance of the gas within the depression 30 becomes longer, and the gas can be located within the depression 30 for a long period of time. That is, the gas within the depression 30 can be efficiently utilized.

[0035] As shown in FIGS. 3 to 5, the gas supply cylinder part 50 includes a discharge end part 51. The discharge end part 51 is the most downstream part in the gas flow path in the gas supply cylinder part 50. The gas supplied from the gas supply source 45 to the gas supply cylinder part 50 is discharged from the discharge end part 51 toward the depression 30.

[0036] As shown in FIGS. 3 and 4, the discharge end part 51 may be located within the depression 30. Thereby, gas can be stably supplied from the gas supply device 40 into the depression 30, and the gas can be used more efficiently.

[0037] As shown in FIGS. 3 to 5, the discharge end part 51 of the gas supply cylinder part 50 may open toward the rear side in the front-rear direction D1. The discharge end part 51 may open in a direction along the outer surface of the bottom of the ship 25 in the region where the discharge end part 51 is installed. That is, the discharge end part 51 may discharge gas in a direction along the outer surface of the bottom of the ship 25 in the region where the discharge end part 51 is installed. The discharge end part 51 may open in the direction in which the depression 30 extends in the region where the gas of the depression 30 is to be supplied, as observed from the width direction D2. The discharge end part 51 may discharge gas in the direction in which the depression 30 extends in the region where the gas of the depression 30 is to be supplied, as observed from the width direction D2. According to these configurations, it is possible to suppress the gas supplied from the gas supply device 40 to the depression 30 of the bottom of the ship 25 from immediately rising to the water surface. That is, the gas in the depression 30 can be used more efficiently.

[0038] As shown in FIG. 3, the gas supply cylinder part 50 may extend from inside the ship of the hull 20 to the outside of the ship. In the example shown in FIG. 3, the depression 30 opens toward the front side in the front-rear direction D1. The discharge end part 51 of the depression 30 is inserted into the depression 30 from the front-side opening in the front-rear direction D1.

[0039] The gas supply device 40 may supply gas into the water as fine bubbles. The gas supplied as fine bubbles is likely to form a bubble film on the bottom of the ship 25. The bubble film can more effectively reduce the friction between the bottom of the ship 25 and the water.

[0040] In the example shown in FIG. 5, the gas supply cylinder portion 50 includes a pipe 52 and an adjustment plate 53. A number of holes 53a are formed in the adjustment plate 53. The holes 53a function as openings at the discharge end portion 51. When the gas is discharged from the holes 53a, the gas is likely to form fine bubbles in the depression 30.

[0041] The adjustment plate 53 is provided at the end of the pipe 52 that serves as the discharge end portion 51. The adjustment plate 53 may be attached to the pipe 52 as a separate member from the pipe 52. The adjustment plate 53 may be integrally formed with the pipe 52.

[0042] The gas supply cylinder portion 50 may include a plurality of branch cylinder portions 55. The branch cylinder portions 55 may be constituted by the pipe 52. Each of the plurality of branch cylinder portions 55 may include a discharge end portion 51 that opens toward the rear side in the front-rear direction D1. That is, each branch cylinder portion 55 may include a discharge end portion 51 that opens toward the rear side in the front-rear direction D1.

[0043] Two or more of the branch cylinder portions 55 included in the plurality of branch cylinder portions 55 may be separately provided in the entire section along the gas flow path. That is, two or more of the branch cylinder portions 55 included in the plurality of branch cylinder portions 55 may not merge in the entire section along the gas flow path.

[0044] Two or more of the branch cylinder portions 55 included in the plurality of branch cylinder portions 55 may merge in a section along the gas flow path. Two or more of the branch cylinder portions 55 included in the plurality of branch cylinder portions 55 may merge on the upstream side along the gas flow path. In the examples shown in FIGS. 1 to 4, the gas supply cylinder portion 50 includes two branch cylinder portions 55. The two branch cylinder portions 55 may merge and be connected to the gas supply source 45.

[0045] The gas supply device 40 is not limited to the examples shown in FIGS. 1 to 4. For example, as shown in FIG. 6, the gas supply cylinder part 50 may not extend outside the ship. As shown in FIG. 6, the gas supply cylinder part 50 may be exposed in the water at the discharge end part 51. The discharge end part 51 of the gas supply cylinder part 50 may open toward the rear side in the front-rear direction D1.

[0046] In the example shown in FIG. 6, the gas supply cylinder part 50 may include a chamber at the discharge end part 51. That is, the gas supply cylinder part 50 may include a chamber box part that forms a chamber at the discharge end part 51. An adjustment plate 53 including a large number of holes 53a may be attached to the chamber box part. A large number of holes 53a may be directly formed in the chamber box part. By providing the chamber box part, the discharge of gas from the gas supply device 40 toward the depression 30 can be stabilized.

[0047] The gas supply cylinder part 50 may include a check valve. The check valve may be installed in the pipe 52 of the gas supply cylinder part 50. In the examples shown in FIGS. 2 and 3, the check valve may be installed in the part of the pipe 52 that extends outside the ship of the hull 20. In this example, gas can be enclosed over a long section of the pipe 52 (the section from the gas supply source 45 to the check valve), and this gas can contribute to the buoyancy increase of the ship 10. In the examples shown in FIGS. 2 and 3, the check valve may be installed in the part of the pipe 52 that is located inside the ship of the hull 20.

[0048] The gas supply cylinder part 50 may include a pressure adjustment chamber. The gas supply cylinder part 50 may include a chamber box part that forms a pressure adjustment chamber. By providing the chamber box part, the pressure of the gas is stabilized in the region downstream of the chamber box part along the gas flow path, and the discharge of gas from the gas supply device 40 toward the depression 30 can be stabilized.

[0049] Next, the plurality of depressions 30 provided in the ship bottom 25 will be described in more detail.

[0050] As shown well in FIG. 4, the plurality of depressions 30 are spaced apart from each other in the width direction D2. Each of the plurality of depressions 30, that is, each depression 30, extends in the front-rear direction D1. Extending in the front-rear direction D1 means not only extending parallel to the front-rear direction D1 but also having a length in the front-rear direction D1. The depression 30 may form an angle of less than 45° with respect to the front-rear direction D1. The angle between the longitudinal direction of the depression 30 and the front-rear direction D1 may be less than 45°, may be 30° or less, may be 20° or less, may be 10° or less. The lower limit of the angle between the longitudinal direction of the depression 30 and the front-rear direction D1 is not particularly set. The angle between the longitudinal direction of the depression 30 and the front-rear direction D1 may be 0° or more, may be greater than 0°.

[0051] As shown in FIG. 3, in the observation from the width direction D2, one or more or all of the depressions 30 may be bent. One or more or all of the depressions 30 may be curved or bent in the observation from the width direction D2. As shown in FIG. 3, one or more or all of the depressions 30 may change their positions in the vertical direction D3 along the front-rear direction D1.

[0052] Furthermore, one or more or all of the depressions 30 may be bent upward in the vertical direction D3 at the rear in the front-rear direction D1. That is, one or more or all of the depressions 30 may be located above in the vertical direction D3 at the rear in the front-rear direction D1. In this example, one or more or all of the depressions 30 may be located above in the vertical direction D3 in the rear portion in the front-rear direction D1 more than other portions. Alternatively, one or more or all of the depressions 30 may be located above in the vertical direction D3 as it goes to the rear side in the front-rear direction D1. One or more or all of the depressions 30 may be bent over the entire length so as to be located above in the vertical direction D3 as it goes to the rear side in the front-rear direction D1.

[0053] As shown in FIG. 4, when observed from below in the vertical direction D3, one or more or all of the depressions 30 may be curved. One or more or all of the depressions 30 may be curved or bent when observed from below in the vertical direction D3. As shown in FIG. 4, one or more or all of the depressions 30 may change their positions in the width direction D2 along the front-rear direction D1.

[0054] Furthermore, one or more or all of the depressions 30 may bend outward in the width direction D2 at the rear in the front-rear direction D1. That is, one or more or all of the depressions 30 may be located outside in the width direction D2 at the rear in the front-rear direction D1. In this example, one or more or all of the depressions 30 may be located outside in the width direction D2 in the rear portion in the front-rear direction D1 more than in other portions. Alternatively, one or more or all of the depressions 30 may be located outside in the width direction D2 as they go to the rear side in the front-rear direction D1. Furthermore, one or more or all of the depressions 30 may be curved over the entire length so as to be located outside in the width direction D2 as they go to the rear side in the front-rear direction D1.

[0055] The outside in the width direction D2 is the side away from the center D2C in the width direction D2. The inside in the width direction D2 is the side close to the center D2C in the width direction D2.

[0056] As shown in FIG. 4, some of the plurality of depressions 30 may be provided on one side in the width direction D2 of the bottom 25. The rest of the plurality of depressions 30 may be provided on the other side in the width direction D2 of the bottom 25.

[0057] As shown in FIG. 4, the plurality of depressions 30 may be symmetrically arranged about a central upper and lower surface CP extending in the vertical direction D3 through the center D2C of the width direction D2. The arrangement positions of the depressions 30 provided on one side in the width direction D2 of the bottom 25 and the arrangement positions of the depressions 30 provided on the other side in the width direction D2 of the bottom 25 may have a plane-symmetrical relationship about the central upper and lower surface CP.

[0058] As shown in FIG. 4, the plurality of recesses 30 may have a symmetrical configuration about a central upper and lower surface CP that extends in the vertical direction D3 through the center D2C in the width direction D2. The recess 30 provided on one side in the width direction D2 of the bottom 25 and the recess 30 provided on the other side in the width direction D2 of the bottom 25 may have a plane-symmetrical relationship about the central upper and lower surface CP.

[0059] As shown in FIG. 4, the screw 23 may not be located on the extension line of each of the plurality of recesses 30. That is, the screw 23 may not be located on the extension line of each recess 30. In other words, the screw 23 may be offset in the width direction D2 from the extension line of each recess 30.

[0060] In the examples shown in FIGS. 1 to 4, the bottom 25 includes two recesses 30. The number of recesses 30 is not limited to two. For example, as shown in FIG. 7, the number of recesses 30 may be four, six, or eight. The number of recesses 30 may be odd, such as three, five, seven, or nine. When the number of recesses 30 is odd, one recess 30 may be provided on the center D2C in the width direction D2.

[0061] The cross-sectional shape of the recess 30 is not particularly limited. As shown in FIGS. 1 and 5, one or more or all of the recesses 30 may have a curved contour in a cross-section orthogonal to the front-rear direction D1. One or more or all of the recesses 30 may have a contour along a part of a circle in a cross-section orthogonal to the front-rear direction D1. One or more or all of the recesses 30 may have a semi-circular contour in a cross-section orthogonal to the front-rear direction D1. One or more or all of the recesses 30 may have a contour along a part of an ellipse in a cross-section orthogonal to the front-rear direction D1. One or more or all of the recesses 30 may have a semi-elliptical contour in a cross-section orthogonal to the front-rear direction D1.

[0062] As shown in FIG. 8, one or more or all of the depressions 30 may have a contour including a straight line in a cross section orthogonal to the front-rear direction D1. As shown in FIG. 8, one or more or all of the depressions 30 may have a polygonal line-shaped contour in a cross section orthogonal to the front-rear direction D1.

[0063] As shown in FIGS. 9 and 10, one or more or all of the depressions 30 may be configured not to include acute-angled or right-angled corners in a cross section orthogonal to the front-rear direction D1. The depression 30 shown in FIG. 9 includes a chamfered corner 32A. The depression 30 shown in FIG. 9 includes a chamfered right-angled corner 32A. The depression 30 shown in FIG. 10 includes an obtuse-angled corner 32B.

[0064] The bottom 25 of the hull 20 may be flat. The bottom 25 of the hull 20 may be inclined as shown in FIG. 2. One or more or all of the depressions 30 may be provided in the gently inclined bottom 25. The bottom 25 includes a low-inclination portion 26, and one or more or all of the depressions 30 may be provided in the low-inclination portion 26. The low-inclination portion 26 is a portion of the bottom 25 where the bottom inclination angle θ25 is 30° or less. The bottom inclination angle θ25 is the angle (°) between the bottom 25 and the width direction D2 in a cross section orthogonal to the front-rear direction D1.

[0065] Note that the depression 30 may end with a shallower depth. The downstream end (rear end) of the depression 30 may be located in a region where the bottom inclination angle θ25 increases, for example, a region where the bottom inclination angle θ25 is 45° or more. According to this example, the gas that has reached the downstream end (rear end) of the depression 30 rises to the water surface WL without unnecessarily disturbing the water flow.

[0066] Next, the operation of the ship 10 having the above configuration will be described.

[0067] The ship 10 can move on the water by the function of the hull 20 including the rudder 22 and the screw 23. During the movement of the ship 10, the gas supply device 40 supplies gas to the bottom 25 of the hull 20. Specifically, the gas supply source 45 supplies air to the gas supply cylinder portion 50, and the gas is discharged from the gas supply cylinder portion 50 toward the bottom 25.

[0068] The gas discharged to the bottom 25 of the ship can reduce the friction between the bottom 25 of the ship and the water by being located between the bottom 25 of the ship and the water. By reducing the friction between the bottom 25 of the ship and the water, the fuel consumption can be improved. By reducing the friction between the bottom 25 of the ship and the water, the speed of the ship 10 can be increased. Furthermore, the gas at the bottom of the ship can increase the buoyancy of the ship, and from this point of view as well, the speed of the ship can be increased. As a result, the environmental load can be reduced.

[0069] By the way, in the prior art (JP2010-120607A), gas was ejected from the bottom of the ship downward in the vertical direction. In such prior art, the gas ejected from the bottom of the ship immediately moves in the width direction from the bottom of the ship and easily floats on the water surface. Therefore, unless a large amount of gas is continuously ejected, effective effects such as friction reduction and buoyancy increase by the gas cannot be expected.

[0070] On the other hand, in the present embodiment, a plurality of depressions 30 to which gas is supplied are provided in the bottom 25 of the ship. The plurality of depressions 30 are spaced apart from each other in the width direction D2. Each of the plurality of depressions 30 extends in the front-rear direction D1.

[0071] Therefore, the gas supplied to the depression 30 can flow in the front-rear direction D1 within the depression 30. That is, it is possible to suppress the gas supplied from the gas supply device 40 to the bottom 25 of the ship from immediately moving in the width direction D2 from the bottom 25 of the ship and floating on the water surface. The gas supplied to the depression 30 can contribute to friction reduction and buoyancy increase over a relatively long period of flowing in the front-rear direction D1 within the depression 30.

[0072] In addition, a plurality of depressions 30 are provided in the bottom 25 of the ship. The plurality of depressions 30 are spaced apart in the width direction D2. That is, in a plurality of portions in the width direction D2, the friction between the bottom 25 and the water is reduced and buoyancy is applied. By adjusting the positions of the plurality of depressions 30 in the width direction D2, it is possible to suppress the straight-ahead performance of the ship 10 from being impaired due to friction reduction caused by the gas in the plurality of depressions 30. In addition, it is possible to suppress the posture of the ship 10 from being disrupted by the buoyancy caused by the gas in the plurality of depressions 30.

[0073] Accordingly, according to the ship 10 according to the present embodiment, the gas supplied from the gas supply device 40 into the depression 30 can be effectively utilized to more efficiently reduce the friction between the bottom 25 and the water, and the buoyancy of the ship 10 can be increased.

[0074] In one of the above-described specific examples, a part of the plurality of depressions 30 is provided on one side in the width direction D2 of the bottom 25 of the ship. The rest of the plurality of depressions 30 are provided on the other side in the width direction D2 of the bottom 25 of the ship. According to this specific example, the depressions 30 are formed on both sides of the center D2C in the width direction D2 of the bottom 25. Therefore, the friction between the hull 20 and the water can be reduced on both sides of the center D2C in the width direction D2. The buoyancy of the ship 10 can be increased on both sides of the center D2C in the width direction D2. As a result, it is possible to suppress the straight-ahead performance of the ship 10 from being impaired due to friction reduction caused by the gas in the plurality of depressions 30. In addition, it is possible to suppress the posture of the ship 10 from being disrupted by the buoyancy caused by the gas in the plurality of depressions 30.

[0075] In one of the above-described specific examples, the plurality of depressions 30 are symmetrically arranged about a plane (center upper and lower surface) CP that extends in the vertical direction D3 through the center D2C in the width direction D2. According to this specific example, it is possible to more effectively suppress the straight-ahead performance of the ship 10 from being impaired due to friction reduction caused by the gas in the plurality of depressions 30. In addition, it is possible to more effectively suppress the posture of the ship 10 from being disrupted by the buoyancy caused by the gas in the depression 30.

[0076] In one of the above-described specific examples, the gas supply device 40 includes a gas supply source 45 that supplies gas, and a gas supply cylinder portion 50 that supplies the gas supplied from the gas supply source 45 toward the recess 30. The gas supply cylinder portion 50 extends outward from the hull 20. According to this specific example, the gas supply cylinder portion 50 extending from inside the ship to the outside of the ship can guide gas into the recess 30. The supply direction (discharge direction) of the gas from the gas supply cylinder portion 50 toward the recess 30 can be adjusted with a high degree of freedom. Therefore, gas can be stably supplied from the gas supply device 40 into the recess 30. It is possible to suppress the gas supplied to the recess 30 from immediately leaking out in the width direction from the recess 30. The flow of gas and water in the front-rear direction D1 within the recess 30 (for example, from the front side toward the rear side) can be stabilized. By these means, the gas supplied from the gas supply device 40 into the recess 30 can be effectively utilized to more effectively achieve friction reduction and buoyancy increase by the gas.

[0077] In one of the above-described specific examples, the gas supply device 40 includes a gas supply source 45 that supplies gas, and a gas supply cylinder portion 50 that supplies the gas supplied from the gas supply source 45 toward the recess 30. The gas supply cylinder portion 50 includes a discharge end portion 51 that opens toward the rear side in the front-rear direction D1. According to this specific example, gas can be stably supplied from the gas supply device 40 into the recess 30. It is possible to suppress the gas supplied to the recess 30 from immediately leaking out in the width direction from the recess 30. Also, the flow of gas and water in the front-rear direction D1 within the recess 30 (for example, from the front side toward the rear side) can be stabilized. By these means, the gas supplied from the gas supply device 40 into the recess 30 can be effectively utilized to more effectively achieve friction reduction and buoyancy increase by the gas.

[0078] In one of the above-described specific examples, the gas supply cylinder portion 50 includes a plurality of branch cylinder portions 55. Each of the plurality of branch cylinder portions 55 supplies gas to another recess 30 included in the plurality of recesses 30. That is, by using the plurality of branch cylinder portions 55, gas can be stably supplied to each recess 30. Thereby, by effectively using the gas supplied from the gas supply device 40 into the recess 30, it is possible to more effectively achieve friction reduction and buoyancy increase by the gas.

[0079] In one of the above-described specific examples, the hull 20 includes a screw 23. The screw 23 is not located on the extension line of each of the plurality of recesses 30. According to this specific example, it is possible to suppress a decrease in the propulsion force due to the rotation of the screw 23 by preventing the screw 23 from entraining the gas discharged from the recess 30.

[0080] In one of the above-described specific examples, one or more or all of the recesses 30 included in the plurality of recesses 30 are bent outward in the width direction D2 on the rear side in the front-rear direction D1. According to this specific example, it is possible to suppress the gas discharged from the recess 30 to the rear side in the front-rear direction D1 from being entrained by the screw 23. Thereby, it is possible to suppress a decrease in the propulsion force due to the rotation of the screw 23.

[0081] In one of the above-described specific examples, one or more or all of the recesses 30 included in the plurality of recesses 30 are bent upward in the vertical direction D3 on the rear side in the front-rear direction D1. According to this specific example, by utilizing the buoyancy of the gas in the water, it is possible to make the gas flow from the front side to the rear side in the front-rear direction D1 in the recess 30 more stable. Therefore, it is possible to stabilize the flow of gas and water in the front-rear direction D1 in the recess 30 (for example, from the front side to the rear side). That is, it is possible to suppress the flow of gas and water in the recess from being disturbed and the gas from leaking out from the middle portion in the front-rear direction of the recess 30. Thereby, by effectively using the gas supplied from the gas supply device 40 into the recess 30, it is possible to more effectively achieve friction reduction and buoyancy increase by the gas.

[0082] In one of the above-described specific examples, the bottom 25 of the ship includes a low-slope portion 26 having an angle of 30° or less with respect to the width direction D2 in a cross-section orthogonal to the front-rear direction D1. One or more or all of the plurality of depressions 30 included in the plurality of depressions 30 are provided in the low-slope portion 26 of the bottom 25 of the ship. According to this specific example, according to the depression 30 provided in the low-slope portion 26, even a shallow depression can stably accommodate a relatively large amount of gas. Thereby, by effectively using the gas supplied into the depression 30 from the gas supply device 40, it is possible to more effectively realize friction reduction and buoyancy increase by the gas. In addition, since the depression 30 can be made shallow, the rigidity of the bottom 25 can be improved.

[0083] In one of the above-described specific examples, one or more or all of the plurality of depressions 30 included in the plurality of depressions 30 do not include acute-angled or right-angled corners in a cross-section orthogonal to the front-rear direction D1. According to this specific example, it is possible to suppress the formation of stagnation in the depression 30 and stabilize the flow of gas and water in the front-rear direction D1 (for example, from the front side to the rear side) in the depression 30. That is, it is possible to suppress the flow of gas and water in the depression from being disturbed and the gas from leaking out from the middle portion in the front-rear direction of the depression 30. Thereby, by effectively using the gas supplied into the depression 30 from the gas supply device 40, it is possible to more effectively realize friction reduction and buoyancy increase by the gas. In addition, since the depression 30 can be made shallow, the rigidity of the bottom 25 can be improved.

[0084] In one embodiment described above, the ship 10 includes a hull 20 and a gas supply device 40 that supplies gas to the bottom 25 of the hull 20. A plurality of depressions 30 to which gas is supplied are provided in the bottom 25. The plurality of depressions 30 are spaced apart from each other in the width direction D2. Each of the plurality of depressions 30 extends in the front-rear direction D1.

[0085] According to this embodiment, the depression 30 linearly extends in the front-rear direction D1. The gas flows in the front-rear direction D1 within the depression 30. That is, it is possible to suppress the gas supplied from the gas supply device 40 to the bottom of the ship 25 from immediately moving in the width direction from the bottom of the ship 25 and rising to the water surface. Friction reduction and buoyancy increase by the gas can be realized over a relatively long period during which the gas is flowing in the front-rear direction within the depression 30. That is, by effectively using the gas supplied from the gas supply device 40 into the depression 30, friction reduction and buoyancy increase by the gas can be realized.

[0086] Although one embodiment has been described with reference to specific examples, the above-described specific examples do not limit one embodiment. The above-described one embodiment can be implemented with various other specific examples, and various omissions, replacements, changes, additions, etc. can be made without departing from the gist thereof.

Explanation of Reference Numerals

[0087] D1: Front-rear direction D1, D2: Width direction D2, D3: Up-down direction D3, D2C: Center, CP: Plane (center upper and lower surfaces), θ25: Bottom of ship inclination angle, 10: Ship, 20: Hull, 21: Main body, 22: Rudder, 23: Screw, 25: Bottom of ship, 26: Low inclination part, 30: Depression, 32A: Corner part, 32B: Corner part, 40: Gas supply device, 45: Gas supply source, 50: Gas supply cylinder part, 51: Discharge end part, 52: Pipe, 53: Adjusting plate, 53a: Hole, 55: Branch cylinder part

Claims

1. A hull, and a gas supply device for supplying gas to the bottom of the hull, comprising: a plurality of depressions for supplying the gas are provided on the bottom of the hull, the plurality of depressions are spaced apart from each other in the width direction, each of the plurality of depressions extends in the front-rear direction, a ship.

2. A part of the plurality of depressions is provided on one side in the width direction of the bottom of the hull, the remaining of the plurality of depressions are provided on the other side in the width direction of the bottom of the hull, the ship according to claim 1.

3. The gas supply device includes a gas supply source for supplying the gas and a gas supply cylinder portion for supplying the gas supplied from the gas supply source toward the depression, the gas supply cylinder portion extends out of the hull to the outside of the ship, the ship according to claim 1.

4. The gas supply cylinder portion includes a discharge end portion that opens toward the rear side in the front-rear direction, the ship according to claim 3.

5. The gas supply device includes a gas supply source for supplying the gas and a gas supply cylinder portion for supplying the gas supplied from the gas supply source toward the depression, the gas supply cylinder portion includes a discharge end portion that opens toward the rear side in the front-rear direction, the ship according to claim 1.

6. The gas supply device includes a gas supply source for supplying the gas and a gas supply cylinder portion for supplying the gas supplied from the gas supply source toward the depression, the gas supply cylinder portion includes a plurality of branch cylinder portions, each of the plurality of branch cylinder portions supplies the gas to another depression included in the plurality of depressions, the ship according to claim 1.

7. The plurality of depressions are symmetrically arranged about a plane extending in the vertical direction through the center in the width direction, the ship according to claim 1.

8. The hull includes a screw, the screw is not located on the extension line of each of the plurality of depressions, the ship according to claim 1.

9. One or more depressions included in the plurality of depressions bend outward in the width direction at the rear side in the front-rear direction, the ship according to claim 1.

10. One or more depressions included in the plurality of depressions bend upward in the vertical direction at the rear side in the front-rear direction, the ship according to claim 1.

11. The bottom of the hull includes a low inclination portion having an angle of 30° or less with respect to the width direction in a cross section orthogonal to the front-rear direction, The ship according to claim 1, wherein one or more of the plurality of depressions are provided in the low-slope portion of the bottom of the ship.

12. The ship according to claim 1, wherein one or more of the plurality of depressions do not include an acute or right-angled corner in a cross-section orthogonal to the longitudinal direction.

Images