JP2023130867A - Vessel - Google Patents

Abstract

To reduce an in-wave resistance increase without increasing smooth underwater resistance in a vessel.SOLUTION: A vessel includes a pitch suppressing member provided in a vessel longitudinal direction more above in a height direction than a water surface rising position in smooth underwater navigation on a bow side in a port side and a starboard side of a hull and the pitch suppressing member has a portion arranged separated from the surface of the hull.SELECTED DRAWING: Figure 2

Description

The present disclosure relates to ships.

In the ocean, waves are a mixture of wind waves and swells. When a ship sails on the ocean, the bow side of the ship moves up and down (pitching) due to waves, increasing navigational resistance. Conventionally, there are techniques described in the following patent documents, for example, as techniques for reducing the increase in navigational resistance of a ship when waves are occurring.

Patent No. 4889238 Patent No. 5103687 Japanese Patent Application Publication No. 2001-247075

As described above, as a technique for reducing the increase in navigational resistance of a ship in flat water, there is a technique in which horizontal plate members are provided on both sides of the bow of the ship along the ship's length. However, there is a desire to further reduce the increase in navigational resistance of ships during waves.

The present disclosure solves the above-mentioned problems, and aims to provide a ship that can reduce the increase in resistance during waves without increasing the resistance in normal water.

In order to achieve the above object, the ship of the present disclosure includes a pitching suppressing member provided on the bow side of the port and starboard sides of the ship body along the ship's length above the water level rise position during smooth water navigation. The pitching suppressing member is partially spaced apart from the surface of the hull.

According to the ship of the present disclosure, increase in resistance during waves can be reduced without increasing resistance in normal water.

FIG. 1 is a schematic side view showing a ship of this embodiment. FIG. 2 is a schematic plan view showing the bow of the ship. FIG. 3 is a cross-sectional view taken along line III--III in FIG. FIG. 4 is a sectional view taken along the line IV-IV in FIG. FIG. 5 is a sectional view showing a modification of the pitching suppressing member. FIG. 6 is a side view showing the bow of the ship for explaining the action of the pitching suppressing member.

Preferred embodiments of the present disclosure will be described in detail below with reference to the drawings. Note that the present disclosure is not limited to this embodiment, and if there are multiple embodiments, the present disclosure also includes a configuration in which each embodiment is combined. In addition, the components in the embodiments include those that can be easily imagined by those skilled in the art, those that are substantially the same, and those that are in the so-called equivalent range.

<Ship>
It is a schematic side view showing a ship of this embodiment.

The ship of this embodiment is preferably a high-speed ship that travels at high speed, but may be other types of ships. Examples of ships include patrol boats, passenger ships (including car ferries), car carriers, container ships, bulk carriers, large oil tankers (VLCC, ULCC), LNG ships, LPG ships, and the like.

As shown in FIG. 1, a ship 10 has a hull 11. As shown in FIG. The hull 11 has a bow 12, a stern 13, a bottom 14, a port side 15, and a starboard side 16. In the following description, the longitudinal direction of the hull 11 will be referred to as the ship length direction X, the left-right direction of the hull 11 will be referred to as the widthwise direction Y, and the vertical direction of the hull 11 will be referred to as the ship height direction Z direction. In addition, the center position of the hull 11 in the transverse direction Y will be referred to as a center line CL, and the waterline indicating the loading limit of cargo in the hull 11 will be referred to as a full load waterline WL.

The hull 11 is partitioned into an engine room 22 by a bulkhead 21 on the stern 13 side, and a main engine (for example, a diesel engine) 23 is disposed in the engine room 22. In the main engine 23, a propeller 25 is connected to an output shaft 24 extending rearward in the longitudinal direction X. The propeller 25 is driven and rotated by the main engine 23 and can obtain propulsion force for the hull 11 . Note that in this embodiment, the propulsion device is the main engine 23, the output shaft 24, the propeller 25, etc., but the configuration is not limited to this, and for example, a water jet or the like may be used.

The hull 11 is provided with a rudder drive device 26 at the stern 13. In the rudder drive device 26, a rudder 28 is connected to a rudder shaft 27 that extends downward in the ship height direction Z. The rudder 28 is rotated by the rudder drive device 26 and can control the traveling direction of the hull 11.

The hull 11 is provided with a bulb 29 at the bottom of the bow 12. The valve 29 can reduce the wave-making resistance of the hull 11. The valve 29 is provided below the load water line WL. However, the valve 29 may not be provided in the hull 11.

Further, the hull 11 is provided with a pitching suppressing member 30 on the bow 12 side. The pitching suppressing member 30 has a V-shape in plan view and is provided so as to extend from the bow 12 toward the port side 15 and the starboard side 16. The bow 12 and the pitching suppressing member 30 of the hull 11 are symmetrical with respect to the centerline CL.

<Configuration of pitching suppression member>
2 is a schematic plan view showing the bow of the ship, FIG. 3 is a sectional view taken along III-III in FIG. 2, FIG. 4 is a sectional view taken along IV-IV in FIG. 2, and FIG. 5 is a modification of the pitching suppression member. FIG.

As shown in FIGS. 1 to 4, the pitching suppressing member 30 is provided on the bow 12 side of the port side 15 and starboard side 16 of the hull 11, above the load waterline WL in the ship height direction Z and along the ship length direction X. Specifically, the pitching suppressing member 30 is set at a height higher than the swell position of the water surface that occurs when navigating in flat water without waves at the nautical speed set at the time of design as a typical speed of the ship 10. placed in position.

The pitching suppressing member 30 has a V-shape when viewed from above (see FIG. 2). The pitching suppression member 30 has one end in the longitudinal direction X fixed to the bow 12, the other end in the longitudinal direction Separate.

That is, the pitching suppressing member 30 includes a port side member 31 disposed on the port side 15 side and a starboard side member 32 disposed on the starboard side 16 side, and one end 31a of the port side member 31 and the starboard side member One end portion 32a of 32 is connected by a connecting portion 33 so as to form a V-shape. In the pitching suppressing member 30, a connecting portion 33, which is one end portion in the ship length direction X, is fixed to the bow 12 by a first support member 34.

Further, in the pitching suppressing member 30, the other end 31b of the port side member 31 in the longitudinal direction It is fixed to the surface 11a of the hull 11 on the port side 15 side by the second support member 35. In the pitching suppressing member 30, the other end 32b of the starboard side member 32 in the longitudinal direction The member 36 is fixed to the surface 11a of the hull 11 on the starboard 16 side. In this case, the other end 31b of the port side member 31 and the other end 32b of the starboard side member 32 are smoothly continuous with the surface 11a of the hull 11 without any difference in level.

Therefore, a gap S is formed between the surface 11a of the hull 11 and the inner surface 30a of the pitching suppressing member 30. The gap S is a gap S1. S2, and gaps S3 and S4 provided between the surface 11a of the hull 11 on the starboard 16 side. The gap S1 is located between the first support member 34 and the second support member 35, and the gap S2 is located between the second support member 35 and the other end 31b. The gap S3 is located between the first support member 34 and the second support member 36, and the gap S4 is located between the second support member 36 and the other end 32b.

It is preferable that the pitching suppressing member 30 has a rectangular cross-sectional shape, and the length in the ship width direction Y is longer than the length in the ship height direction Z. However, the pitching suppressing member 30 is not limited to a rectangular cross-sectional shape, but may have a polygonal cross-sectional shape, a circular cross-sectional shape, an elliptical cross-sectional shape, or the like. The pitching suppressing member 30 preferably has an overhang length Wa that projects outward in the ship width direction Y from the surface 11a of the hull 11 in a range of 0.2% to 1.0% of the ship length L. It is preferable that the gap length Wb in the gap S in the ship width direction Y between the surface 11a of 11 and the pitching suppressing member 30 is in the range of 20% to 50% of the overhang length Wa. Further, the gap length Wb is preferably in the range of 0.04% to 0.5% of the ship length L. However, the overhang length Wa and the gap length Wb are not limited to the above-mentioned ranges, and may be set as appropriate depending on the type of ship 10, the shape of the hull 11, etc.

Further, the overhang length Wa and the gap length Wb in the pitching suppressing member 30 are preferably constant in the ship's ship direction X, but may be made to gradually increase toward the rear side in the ship's ship direction X. . In addition, since the other ends 31b and 32b of the pitching suppressing member 30 are smoothly continuous with the surface 11a of the hull 11 without a step, the overhang length Wa and the gap length Wb are equal to the other ends 31b and 32b. becomes smaller.

The length La of the pitching suppressing member 30 in the longitudinal direction X is in the range of 3% to 7% of the longitudinal length L. In this case, the pitching suppressing member 30 has the port side member 31 and the starboard side member 32 connected by the connecting part 33, but the port side member 31 and the starboard side member 32 may be configured as separate members. . Furthermore, the port side member 31 and the starboard side member 32 may be composed of a plurality of members. That is, the pitching suppressing member 30 may be provided integrally and continuously along the ship length direction X, or may be provided intermittently. Further, the positions of the first support member 34 and the second support members 35, 36 are not limited to the above-mentioned positions.

Further, the pitching suppressing member 30 is arranged along a first line L1 in which a direction protruding from the surface 11a of the hull 11 in the ship width direction Y is parallel to the load waterline WL. However, the direction in which the pitching suppressing member 30 projects from the surface 11a of the hull 11 is not limited to the direction along the first line L1. For example, as shown in FIG. 5, the pitching suppressing member 30 may be arranged along a second line L2 projecting outward and perpendicular to the surface 11a of the hull 11.

In other words, the pitching suppressing member 30 has a direction in which the direction protruding from the surface 11a of the hull 11 in the transverse direction Y is aligned with the first line L1 protruding from the surface 11a of the hull 11 in the transverse direction Y, and the surface 11a of the hull 11. It is preferable that the angle θ is within the range of the second line L2 that is perpendicular to the second line L2 that projects outward. However, the angle of the pitching suppressing member 30 does not necessarily need to be set within this range of angle θ, and may be set as appropriate depending on the type of ship 10, the shape of the hull 11, etc.

Moreover, the pitching suppressing member 30 is arranged so that the direction along the ship's length direction X is parallel to the load waterline WL. However, if necessary, the pitching suppressing member 30 may be inclined so that the rear end is located above the front end in the ship height direction Z. In this case, the pitching suppressing member 30 may have a linear shape in the longitudinal direction X, or may have a bent or curved shape that projects downward. Further, the pitching suppressing member 30 may include a tapered portion or a curved portion such that the width of the gap S widens downward at the lower end portion of the inner surface 33a.

<Effect of pitching suppression member>
FIG. 6 is a side view showing the bow of the ship for explaining the action of the pitching suppressing member.

As shown in FIG. 6, when the ship 10 is sailing in flat water without waves, the bulge W1 on the water surface does not reach the lower surface of the pitching suppressing member 30, and the pitching suppressing member 30 becomes a resistance to navigation. There isn't. On the other hand, when the ship 10 is navigating in waves, seawater affected by the waves collides with the lower surface of the pitching suppressing member 30, and pitching in the hull 11 is reduced.

That is, seawater affected by waves travels along the surface 11a of the hull 11 and reaches the lower surface of the pitching suppressing member 30, and some seawater W2 collides with the lower surface of the pitching suppressing member 30 and descends. However, some seawater W3 rises through the gap S of the pitching suppressing member 30. At this time, the flow velocity of the seawater W3 increases as it passes through the gap S of the pitching suppressing member 30, and the resistance between the seawater W3 and the surface 11a of the hull 11 and the inner surface 30a of the pitching suppressing member 30 increases. Then, pitching (pitching) in which the bow 12 side of the hull 11 moves up and down is attenuated by the damping effect. As a result, even when the ship 10 is navigating in waves, pitching (pitching) on the bow 12 side of the ship 10 is suppressed, and stable navigation can be achieved.

[Actions and effects of this embodiment]
The ship according to the first aspect is provided with a vessel located on the bow 12 side of the port side 15 and starboard side 16 of the hull 11 along the ship's length direction A part of the pitching suppressing member 30 is spaced apart from the surface 11a of the hull 11.

According to the ship according to the first aspect, waves during navigation in waves travel along the surface 11a of the hull 11 and reach the pitching suppressing member 30, and a part of the waves pass through the gap S of the pitching suppressing member 30. Rise. At this time, as the seawater passes through the gap S of the pitching suppressing member 30, the flow velocity increases and the resistance increases, so that the pitching (pitching) of the bow 12 in the hull 11 is attenuated by the damping effect. As a result, the increase in resistance during waves can be reduced without increasing the resistance of the vessel 10 in flat water.

In the ship according to the second aspect, one end of the pitching suppressing member 30 in the longitudinal direction X is fixed to the bow 12, the other end in the longitudinal direction portion is separated from the surface 11a of the hull 11. Thereby, a gap S can be formed at an appropriate position between the hull 11 and the pitching suppressing member 30.

In the ship according to the third aspect, the pitching suppressing member 30 has a V-shape in plan view, one end in the longitudinal direction X is fixed to the bow 12 by the first support member 34, and each other end in the longitudinal direction are fixed to the surface 11a of the hull 11 on the port 15 side and the starboard 16 side by second support members 35 and 36. Thereby, a gap S of an appropriate width can be formed between the hull 11 and the pitching suppressing member 30, and the pitching suppressing member 30 can be fixed to the hull 11 with appropriate strength.

In the ship according to the fourth aspect, the projecting length Wa of the pitching suppressing member 30 projecting from the surface 11a of the hull 11 in the ship width direction Y is in the range of 0.2% to 1.0% of the ship length L. The gap length Wb in the ship width direction Y between the surface 11a of the hull 11 and the pitching suppressing member 30 is in the range of 20% to 50% of the overhang length Wa. Thereby, the pitching suppressing member 30 has an appropriate width, and the pitching of the bow 12 of the hull 11 can be effectively damped.

In the ship according to the fifth aspect, the pitching suppressing member 30 has a first line L1 projecting from the surface 11a of the hull 11 in the ship width direction Y, and a second line L1 projecting outward perpendicular to the surface 11a of the hull 11. It is provided at an angle θ within a range with the line L2. Thereby, the pitching suppressing member 30 is at an appropriate angle, and the pitching of the bow 12 of the hull 11 can be effectively damped.

In the ship according to the sixth aspect, the length of the pitching suppressing member 30 in the ship length direction X is in the range of 3% to 7% of the ship length L. Thereby, the pitching suppressing member 30 has an appropriate length, and the pitching of the bow 12 of the hull 11 can be effectively damped.

10 Ship 11 Hull 11a Surface 12 Bow 13 Stern 14 Bottom 15 Port side 16 Starboard side 30 Pitching suppressing member 31 Port side member 31a One end portion 31b Other end portion 32 Starboard side member 32a One end portion 32b Other end portion 33 Connection portion 34 First support Member 35, 36 Second support member S, S1, S2, S3, S4 Gap

Claims (6)

A pitching suppressing member is provided on the bow side of the port and starboard sides of the hull, and is provided along the ship's length above the water level rise position during smooth water navigation,
The pitching suppressing member is arranged such that a part thereof is spaced apart from the surface of the hull.
ship. The pitching suppressing member has one end in the longitudinal direction fixed to the bow, the other end in the longitudinal direction fixed to the surface of the hull, and an intermediate part in the longitudinal direction spaced apart from the surface of the hull.
A ship according to claim 1. The pitching suppressing member has a V-shape in plan view, one end in the longitudinal direction is fixed to the bow by a first support member, and each other end in the longitudinal direction is fixed to the port side and the port side by a second support member. fixed to the surface of the hull on the starboard side;
A ship according to claim 2. The pitching suppressing member has a projecting length protruding from the surface of the hull in the width direction of the ship in a range of 0.2% to 1.0% of the ship's ship length, and the pitching suppressing member The gap length in the ship width direction is in the range of 20% to 50% of the overhang length,
A ship according to any one of claims 1 to 3. The pitching suppressing member is provided at an angle within a range of a first line protruding from the surface of the hull in the transverse direction and a second line protruding outward perpendicular to the surface of the hull,
A ship according to any one of claims 1 to 4. The length of the pitching suppressing member in the ship's ship direction is in the range of 3% to 7% of the ship's ship's ship.
A ship according to any one of claims 1 to 5.

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