JP2023128975A - Three shell type passenger vessel - Google Patents

Abstract

To provide a passenger vessel loaded with a main engine with a large propeller and great output.SOLUTION: A three shell type passenger vessel 1 includes a main hull 10 of transom-stern and a pair of transom-stern side unit floats 20, 30 arranged in parallel on both broadsides of the main hull 10. Bottom of the main hull 10 has bow side up to before the propeller shaft 9 is projected outside the vessel be in a straight V shape. Bottom RS on stern side includes a rising bottom unit 12 gradually becoming shallower going toward a stern direction continued from the bottom 11 in a straight V shape and a stern bottom unit 14 shallower than the bottom 11 extending horizontally in straight V shape. The depth of the stern bottom unit 14 is shallower than the side unit floats 20, 30 on both broadsides and a propeller 4 is rotated in a position which is the shallowest between the rising bottom unit 12 and the stern bottom unit 14.SELECTED DRAWING: Figure 1

Description

The present invention relates to a trimaran passenger ship, and more particularly to a relatively small trimaran passenger ship that accommodates a large diameter propeller.

Patent Document 1 discloses a shape of a stern portion that allows accommodation of a propeller with a large diameter in order to increase the propulsion efficiency of a ship. According to the same document, the shape of the stern part is such that the stern end is located extensively below the water surface, and the bottom of the ship gradually rises toward the bow until it touches the maximum diameter of the propeller. The bottom of the ship gradually descends, resembling a hollowed out bottom of the ship. Patent Document 2 discloses a technique for reducing wave-making resistance by providing a wedge portion on the bottom surface of the stern as a method for reducing wave-making resistance of a high-speed boat. According to this document, the wave-making resistance is reduced by accelerating the water flow in the wedge portion and causing the accelerated water flow to flow horizontally or downward. Furthermore, Patent Document 3 discloses a stern structure for a high-speed boat that reduces wave-making resistance by accelerating the flow at the stern and rectifying the water flow behind the propulsion propeller. According to this document, a pair of fins are provided on the stern side so as to sandwich an extension line passing through the propeller shaft from both sides.

Utility Model Publication No. 56-4997 Japanese Patent Application Publication No. 9-52591 Japanese Patent Application Publication No. 2006-51895

In the technique of Patent Document 1, the wedge effect as shown in Patent Document 2 can be obtained by a shape that is gradually lowered from the position of the propeller to the stern. On the other hand, in the technology of Patent Document 1, the bottom of the ship is gradually raised from the stern to the bow, and is raised highest around the propeller, so fins are provided from both sides toward the water so as to sandwich the propeller. It is necessary to prevent air from entering from the ship's side. In addition, when using a large propeller, it is necessary to install a main engine with a large output, and if the bottom of the ship is hollowed out, the buoyancy and stability will be reduced, so the size of the main engine that can be installed must be determined. There was a limit.

The present invention has been made in response to such conventional circumstances, and an object of the present invention is to provide a passenger ship equipped with a large propeller and a main engine with a large output.

In order to achieve the above object, the trimaran passenger ship of the present invention has a main hull with a transom stern,
a pair of side floats of a transom stern, which are shorter and smaller in volume than the main hull, aligned with the stern of the main hull, and arranged in parallel on both sides of the main hull;
Equipped with a main hull and a deck that covers the left and right side floats,
The bottom of the main hull has a straight V-shape on the bow side up to the point where the propeller shaft protrudes out of the boat.
and the stern side is provided with an ascending ship bottom that gradually becomes shallower toward the stern following the straight V-shaped ship bottom, and a stern ship bottom that extends horizontally and is shallower than the straight V ship bottom,
A shallowest bottom between the rising bottom and the stern bottom is provided, a propeller is disposed at this position, the depth of the stern bottom is shallower than the side floats on both sides, and the bottom of the stern is shallower than the bottom of the rising ship. The propeller is characterized by rotating at the shallowest position between the bottom of the ship and the bottom of the descending ship.

In the trimaran passenger ship of the present invention, even the shallowest stern bottom is shallower than the side floats. Therefore, as the ship's speed increases, the water flow displaced by the bow enters between the main hull and the side floats and is sucked into the propeller, thereby suppressing air from entering the ship's side.

The trimaran passenger ship of this embodiment is shown, with FIG. 1A being a front view, FIG. 1B being a side view, and FIG. 1C being a bottom view. 2A, 2B, and 2C are views showing a Y1-Y1 cross section, a Y2-Y2 cross section, and a Y3-Y3 cross section, respectively. FIG. 3A, 3B, and 3C are X1-X1 cross-sections, X2-X2 cross-sections, and X3-X3 cross-sections, respectively, and FIG. 3D is a view showing the rear side. FIG. FIG. 4A is a cross-sectional view of the trimaran passenger ship 1 cut along the waterline WL, and FIG. 4B is a side view of the water flow at the bottom of the ship. be. 5A is a bottom view, and FIGS. 5B, 5C, 5D, and 5E are X4-X4 section, X5-X5 section, X6-X6 section, Y4- This is a Y4 cross section, and FIG. 5F is a diagram showing the back surface.

[Example 1]
FIG. 1 shows a trimaran passenger ship 1 of this embodiment, with FIG. 1A being a front view, FIG. 1B being a side view, and FIG. 1C being a bottom view. Trihull type passenger ship 1 is a small vessel designed with a depth of the limit size in order to comply with the domestic regulations for ships of 19 tons (less than 20 tons (total volume: 139.8 ^m2 ) and less than 24 m in length). The trimaran passenger ship 1 has a main hull 10 and side floats 20 and 30 arranged in parallel on both sides of the main hull 10.The side floats 20 and 30 are longer than the length L1 of the main hull 10. It also has a short L2 and a small volume.Since speed is proportional to the length of the ship, the length L1 of the main hull 10 is increased to ensure the length of the submerged hull part, and the speed is increased. The side floats 20 and 30 are equipped with intake valves (not shown) so that they can be used as fresh water tanks to transport emergency supplies in the event of a disaster. The position 30 is near the stern of the main hull 10. The stern positions of the side floats 20 and 30 are aligned with the stern position of the main hull 10, and constitute the stern S of the trimaran passenger ship 1. On both sides of the stern S side, electrically operated folding ramps 18 are installed on both sides from the deck 2 (only one side is shown in the figure), and a thruster 16 is provided at the bow.

The main hull 10 and the side floats 20, 30 are connected to the deck 2 and below the deck 2 by connecting parts 40, 50. The deck 2 covers the main hull 10 and side floats 20, 30. It is also possible to make the connecting parts 40 and 50 hollow and use them as fresh water tanks under the deck 2. Both the main hull 10 and side floats 20 and 30 have a transom stern, and the deck 2 (stern deck) on the stern S side is wide. The bottoms of the side floats 20, 30 are straight from the tip to the rear end. A keel KL may be attached to the bottom of the side floats 20, 30 over the entire length of the bottom in order to obtain stable straightness.

In FIG. 1C, the cross section of the main hull 10 is a straight V-shape in which the bottom 11 on the bow B side is V-shaped up to the point where the propeller shafts 9 arranged in parallel protrude outside the ship, and the stern S The side bottom RS has a shape that breaks the straight V shape. The center C of the bottom 11 of the main hull 10 is the same or deeper than the side floats 20 and 30 in most of the range EX1 from the bow B to just before the propeller shaft 9 at the position where they overlap in the width direction from side to side. There is. However, this relationship is reversed at the bottom RS in the ranges EX2, EX3, and EX4 on the stern S side, and the side floats 20 and 30 are deeper. The depths of the ranges EX2, EX3, and EX4 on the stern S side of the main hull 10, side floats 20, and 30 at the bottom RS will be described further later using FIG. 2.

FIG. 2 is a diagram showing a cross section of the trimaran passenger ship 1, and FIGS. 2A, 2B, and 2C are a Y1-Y1 cross section, a Y2-Y2 cross section, and a Y3-Y3 cross section (see FIG. 1A), respectively.

The main hull 10 and side floats 20, 30 are in a transom stern. The main hull 10 has a transom stern because (1) the steering gear room 19 is provided on the stern S side and the steering gear 8 is stored therein, and (2) the submerged area of the hull is increased to increase buoyancy. This is to make it bigger. In addition, the reason why the side floats 20 and 30 are made into a transom stern is that the trimaran passenger ship 1 is used as a passenger ship, and the deck 2 on the stern S side is flat so that an unspecified number of people can go around. This is to make it possible.

The main hull 10 is provided with a passenger cabin 6, which has a seating capacity (3 people x 9 rows x both sides = 54 people). Furthermore, the engine room 15 is equipped with two main engines 5 with a maximum horsepower of 774 PS (569 KW) in order to achieve a speed of 25 knots or more. Since the main engine 5 has a large output and is large enough to come out from the deck 2, the deck 2, which serves as a ceiling only for the engine room 15, is raised high. Because the two main engines 5 are placed across the width of the main hull 10, the main hull 10 becomes heavy and unstable, so by providing side floats 20 and 30 to form a trimaran, it becomes stable and buoyant. It has gained. The wheelhouse 17 is located in the middle to reduce the tonnage, leaving only space for people to stand.

In FIG. 2B, the bottom of the main hull 10 has a straight V-shape on the bow B side, but the bottom RS on the stern S side is deformed and hollowed out into an arched shape. The bottom RS includes a rising bottom 12 that gradually becomes shallower toward the stern S following the bottom 11, a descending bottom 13 that gradually becomes deeper from the bottom BV toward the stern S following the rising bottom 12, and a descending bottom 13 that gradually becomes shallower toward the stern S. Following the bottom part 13, a horizontally extending stern bottom part 14 to which a rudder 7 is attached is provided. The bottom part BV is the shallowest part of the ship, and the propeller 4 is arranged corresponding to this position.

FIG. 3A is a cross section at the boundary between the bottom 11 and the bottom 12 of the rising ship. FIG. 3B is a cross section of the rising boat bottom 12 and the descending boat bottom 13 at the boat bottom BV. The bottom BV of the ship is the shallowest, and the propeller 4 rotates at this position. Moreover, FIG. 3C is a cross section at the stern bottom part 14. The depth of the stern bottom 14 is shallower than the straight V-shaped bottom 11 on the bow B side. The bottom RS around the propeller 4 is hollowed out in the shape of a raised bow by the rising bottom 12, the descending bottom 13, and the stern bottom 14. Therefore, in order to comply with the regulations for ships with a length of less than 24 m, two large propellers 4 can be installed within the depth limit. In addition, the propeller 4 and the bottom of the ship must be separated by at least 20 cm in consideration of vibrations, ship speed, etc., but the shape of the bottom allows for a distance of 30 cm from the propeller 4.

The main hull 10 has a bottom where the propeller 4 is located, including the vicinity of the ship's side, which is generally shallower than other parts. This is because two main engines 5 are mounted, large propellers 4 are arranged in parallel, and the rotational diameter of the propellers 4 approaches the ship's side.

Deep wedge portions 21 are provided on both sides of the stern bottom portion 14. The wedge portion 21 is provided as a continuation of the straight V shape from the bow B. Since the wedge portion 21 is deeper than the stern bottom portion 14, the water flow WP is sandwiched between the wedge portions 21 as shown in FIG. 3D, and flows downward in a unified state. . In this way, the downward flow of the water flow WP improves the propulsion (progressive pushing force). In addition, the undertow behind the stern S is less likely to rise to the sea surface, and waves generated at fishing ports and aquaculture rafts can be suppressed.

The rudder 7 extends to a deeper position than the propeller 4, and has greater resistance to water flow than usual. As a result, the force applied to the rudder 7 is increased due to the pressure of the water flow, and the rudder 7 is swung from side to side at a deeper position, resulting in better steering. Furthermore, at the position of the bottom RS, even the shallowest stern bottom 14 is shallower than the side floats 20 and 30, except for a part of the rising bottom 12 (connection with the bottom 11).

Note that when the keel KL is attached to the bottom of the side floats 20 and 30 (in FIG. 1A, the keel KL is attached to the bottom of the side floats 20 and 30), the deep part of the keel KL shall be regarded as the bottom of the side floats 20, 30.

FIG. 4 is a diagram showing the operation of the trimaran passenger ship 1 of this embodiment. FIG. 4A is a cross section of the trimaran passenger ship 1 cut along the waterline WL, and FIG. 4B is a diagram showing the flow of water on the bottom of the ship from the side. This is a view. FIG. 4A shows how the water flow WS displaced by the bow B enters between the main hull 10 and the side floats 20 and 30 as the ship speed increases. Since the water current WS sandwiched between the main hull 10 and the side floats 20 and 30 is sucked into the propeller 4 of the shallow bottom part BV, the intrusion of air from the side is suppressed. The deeper the bottom of the side floats 20, 30 is than the depth of the bottom BV, the more effective it is.

In FIG. 4B, since the rising boat bottom part 12 and the descending boat bottom part 13 are provided, a downward force as indicated by the arrow is generated in the water flow WP from the propeller 4, and the water flow WP flows downward (in a deeper direction) than horizontally. Therefore, wave-making resistance can be reduced by causing the accelerated water flow to flow horizontally or downward.

[Example 2]
In the previous embodiment, the bottom RS on the stern S side was shaped like a hollowed-out bow, but in this embodiment, considering ease of manufacture, the bottom RS on the side It adopts a flat bottom shape with a flat plate across the entire width, and only the propeller 4 is recessed into an egg shape. In this embodiment, the same reference numerals are given to the components corresponding to the previous embodiments.

A bottom view is shown in FIG. 5A. In the figure, the bottom RS of the main hull 10 includes a bottom 11, a flat-bottomed rising bottom 12 that gradually becomes shallower toward the stern S, and a horizontal bottom RS to which the rudder 7 is attached following the rising bottom 12. It has an extending flat-bottomed stern bottom section 14. Instead of the descending boat bottom 13 of the previous embodiment, an egg-shaped depression 22 is provided spanning the rising boat bottom 12 and the stern boat bottom 14, where the boat bottom BV near the propeller 4 is shallowest. The depressions 22 are provided corresponding to the propellers 4, respectively. FIG. 5B is a cross section at the boundary between the ship bottom 11 and the rising ship bottom 12. FIG. 5C is a cross section of the rising boat bottom 12 and the descending boat bottom 13 at the boat bottom BV. The bottom BV of the ship is the shallowest, and the propeller 4 rotates at this position. Moreover, FIG. 5D is a cross section at the stern bottom part 14. FIG. 5E is a Y4-Y4 cross section in FIG. 5A, and the shallow position of the egg-shaped recess 22 corresponds to the ship bottom BV.

The depth of the stern bottom 14 is shallower than the straight V-shaped bottom 11 on the bow B side. The position of the bottom RS is shallower than the side floats 20 and 30, except for a part of the rising bottom 12 (connection with the bottom 11). Therefore, the water flow WP is sandwiched between the side floats 20 and 30 as shown in FIG. 5F, and flows downward in a unified state. Although the effect is inferior to that of the wedge portion 21 in the previous embodiment, the downward flow of the water stream WP improves propulsion. In addition, the undertow behind the stern S is less likely to rise to the sea surface, and waves generated at fishing ports and aquaculture rafts can be suppressed.

In addition, although the bottom part BV has a shallower side than the previous embodiment, as the ship speed increases, the water flow WS displaced by the bow B spreads between the main hull 10 and the side floats 20 and 30. The effect shown in FIG. 4A, in which the water current WS sandwiched between the two is sucked into the shallow propeller 4 of the bottom BV, and the entry of air from the ship's side is suppressed, can be obtained in the same way.

1 Trihull passenger ship 2 Deck 4 Propeller 5 Main engine 6 Passenger cabin 7 Rudder 8 Steering gear 9 Propeller shaft 10 Main hull 11 Bottom 12 Rising bottom 13 Descending bottom 14 Stern bottom 15 Engine room 16 Thruster 17 Wheelhouse 18 Folding Type gangway 19 Steering gear room 21 Wedge section 20, 30 Side float 40, 50 Connection section

Claims (4)

The main hull of the transom stern,
a pair of side floats of a transom stern, which are shorter and smaller in volume than the main hull, aligned with the stern of the main hull, and arranged in parallel on both sides of the main hull;
Equipped with a main hull and a deck that covers the left and right side floats,
The bottom of the main hull has a straight V-shape on the bow side up to the point where the propeller shaft protrudes out of the boat.
and the stern side includes a rising ship bottom that gradually becomes shallower toward the stern following the straight V-shaped ship bottom, and a stern ship bottom that extends horizontally and is shallower than the straight V-shaped ship bottom,
A shallowest bottom between the rising bottom and the stern bottom is provided, a propeller is disposed at this position, the depth of the stern bottom is shallower than the side floats on both sides, and the bottom of the stern is shallower than the bottom of the rising ship. A trimaran passenger ship characterized by a propeller rotating at the shallowest position between the bottom of the ship and the bottom of the descending ship.
2. The trimaran passenger ship according to claim 1, wherein the ascending vessel bottom, the disembarking vessel bottom, and the stern vessel bottom have a flat bottom shape with a flat plate shape spanning the entire width of the ship's side. Passenger ship.
The trimaran passenger ship according to claim 1, characterized in that an egg-shaped recess is provided across the rising ship bottom and the stern ship bottom, and the egg-shaped recess is the shallowest ship bottom. Trihulled passenger ship.
2. The trimaran passenger ship according to claim 1, wherein a descending boat bottom section that gradually deepens toward the stern is provided between the rising boat bottom section and the stern boat bottom section, and the descending boat bottom section is provided between the rising boat bottom section and the descending boat bottom section. A trimarin passenger ship characterized by a shallow bottom.