Trimaran passenger ship

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

[Technical field]

[0001] The present invention relates to trimaran passenger ships, and more particularly to relatively small trimaran passenger ships housing large diameter propellers. [Background technology]

[0002] Patent Document 1 discloses a stern shape that allows a large diameter propeller to be accommodated in order to improve the propulsion efficiency of a ship. According to this document, the shape of the stern is such that the stern end is located below the water surface over a wide area, and the bottom of the ship gradually rises from this point to the part that contacts the maximum diameter of the propeller toward the bow, and the bottom of the ship gradually descends from the propeller vicinity forward, creating a shape like a hollowed-out bottom. Patent Document 2 discloses a technology for reducing wave-making resistance of a high-speed ship by providing a wedge section on the bottom surface of the stern. According to this document, the wave-making resistance is reduced by accelerating the water flow in the wedge section and flowing the accelerated water flow horizontally or downward. Furthermore, Patent Document 3 discloses a stern structure of a high-speed ship that reduces wave-making resistance by accelerating the flow in the stern and rectifying the water flow behind the propeller for propulsion. 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. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] Japanese Utility Model Application Publication No. 56-4997 [Patent Document 2] Japanese Patent Application Publication No. 9-52591 [Patent Document 3] JP 2006-51895 A Summary of the Invention [Problem to be solved by the invention]

[0004] In the technology of Patent Document 1, the shape of the ship gradually descends from the propeller position to the stern, which makes it possible to obtain the wedge effect shown in Patent Document 2. On the other hand, in the technology of Patent Document 1, the ship's bottom is gradually raised from the stern toward the bow, and is most elevated around the propeller, so fins must be provided on both sides of the ship facing toward the water to sandwich the propeller and prevent air from entering from the sides. In addition, when using a large propeller, a main engine with a large output must be installed, and a shape that hollows out the ship's bottom reduces buoyancy and stability, so there is a limit to the size of the main engine that can be installed.

[0005] The present invention has been made in response to the above-mentioned conventional circumstances, and has an object to provide a passenger ship equipped with a large propeller and a main engine with large output. [Means for solving the problem]

[0006] In order to achieve the above object, the trimaran passenger ship of the present invention has a transom stern main hull and A transom stern that is shorter and smaller in volume than the main hull and is aligned with the stern of the main hull and is arranged side by side on both sides of the main hull and a pair of hulls with a straight bottom from the front to the rear and a side float of a connecting portion that connects the main hull and the pair of side floats at a distance; , The vessel has a main hull and a deck covering the left and right side floats. The bottom of the main hull is The depth from the bow to the front of the propeller shaft is the same as or deeper than the bottom of the pair of side floats, and The bow side up to the point where the propeller shaft protrudes outside the ship is a straight V shape. The stern side is provided with a rising bottom section which is gradually shallower in the stern direction following the straight V-shaped bottom section, and a stern bottom section which extends horizontally and is shallower than the straight V-shaped bottom section. The bottom of the lift vessel; The above Between the stern and the bottom of the ship To The shallowest part of the ship's bottom is provided, and the propeller is placed at this position. The depth of the stern bottom is The bottom of the ship Shallower than Last Updated The above also becomes shallower. Position of the bottom of the ship in The above The propeller began to rotate. The water flow sandwiched between the main hull and the pair of side floats is sucked into the propeller at the position of the bottom of the vessel where the water flow is shallowest. It is characterized by: Effect of the Invention

[0007] In the trimaran passenger ship of the present invention, even the shallowest stern bottom is shallower than the side floats. Therefore, as the ship speed increases, the water current pushed aside by the bow enters between the main hull and the side floats and is sucked into the propeller, thereby suppressing the inflow of air from the side. [Brief description of the drawings]

[0008] [Figure 1] 1A shows a trimaran passenger ship of this embodiment, with FIG. 1A being a front view, FIG. 1B being a side view, and FIG. 1C being a bottom view. [Diagram 2] 2A, 2B, and 2C are cross-sectional views of a trimaran passenger ship, and are respectively views of the Y1-Y1 cross-section, the Y2-Y2 cross-section, and the Y3-Y3 cross-section. [Diagram 3] 3A, 3B and 3C are cross-sectional views of a trimaran passenger ship, respectively taken along the lines X1-X1, X2-X2 and X3-X3, and FIG. 3D is a view showing the rear surface. [Figure 4] 4A and 4B are diagrams showing the operation of the trimaran passenger ship 1 of this embodiment, where FIG. 4A is a cross section of the trimaran passenger ship 1 taken along the waterline WL, and FIG. 4B is a side view of the water flow at the bottom of the ship. [Diagram 5] FIG. 5A shows a trimaran passenger ship of another embodiment, with FIG. 5A being a bottom view, FIG. 5B, FIG. 5C, FIG. 5D, and FIG. 5E being X4-X4 cross sections, X5-X5 cross sections, X6-X6 cross sections, and Y4-Y4 cross sections, respectively, and FIG. 5F being a view showing the rear view. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0009] [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. The trimaran passenger ship 1 is a domestic 19-ton (less than 20-ton (total volume 139.8 m) 2It is a small vessel designed with a depth of the limit size to comply with the regulations for vessels with a length of less than 24 m (less than 24 m). The trimaran passenger ship 1 has a main hull 10 and side floats 20, 30 arranged side by side on both sides of the main hull 10. The side floats 20, 30 have a length L2 shorter than the length L1 of the main hull 10 and a small volume. Since the speed is proportional to the length of the ship, the length L1 of the main hull 10 is made longer to ensure the length of the submerged hull portion and to achieve speed. The side floats 20, 30 are equipped with water intakes (not shown) so that they can be used as fresh water tanks to transport emergency supplies in the event of a disaster. The side floats 20, 30 are located toward the stern of the main hull 10. The stern positions of the side floats 20, 30 are aligned with the stern position of the main hull 10 to form the stern S of the trimaran passenger ship 1. On both sides of the stern S side, electrically operated folding ladders 18 are installed from the deck 2 to both sides (only one is shown in the figure), and the bow is equipped with a thruster 16.

[0010] 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 the side floats 20, 30. The connecting parts 40, 50 can be hollowed out and used as fresh water tanks below the deck 2. Both the main hull 10 and the side floats 20, 30 are 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 front to the rear. A keel KL may be attached to the bottoms of the side floats 20, 30 over the entire length of the bottom to ensure stable straightness.

[0011] In Fig. 1C, the cross section of the main hull 10 has a straight V-shape on the bow B side up to the point where the parallel-arranged propeller shafts 9 protrude outboard, and the bottom RS on the stern S side 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, 30 in most of the range EX1 from the bow B to just before the propeller shaft 9, where they overlap in the width direction from side to side. However, this relationship is reversed in the bottom RS in the ranges EX2, EX3, and EX4 on the stern S side, where the side floats 20, 30 are deeper. The depth of the bottom RS of the main hull 10 and the side floats 20, 30 in the ranges EX2, EX3, and EX4 on the stern S side will be described further below using Fig. 2.

[0012] FIG. 2 is a cross-sectional view of the trimaran passenger ship 1, and FIGS. 2A, 2B, and 2C are Y1-Y1 cross-sections, Y2-Y2 cross-sections, and Y3-Y3 cross-sections, respectively (see FIG. 1A).

[0013] The main hull 10 and the side floats 20, 30 are configured as transom sterns. The main hull 10 is configured as a transom stern because (1) a steering room 19 is provided on the stern S side to store the steering gear 8 therein, and (2) to increase the submerged area of ​​the hull and therefore the buoyancy. In addition, the side floats 20, 30 are also configured as transom sterns because the trimaran passenger ship 1 is used as a passenger ship, and the deck 2 on the stern S side is flat to allow an unspecified number of people to travel around.

[0014] The main hull 10 is provided with a passenger cabin 6, and has a seating capacity of 54 people (3 people x 9 rows x both sides). The engine room 15 is equipped with two main engines 5 with a maximum horsepower of 774 PS (569 KW) to achieve a speed of 25 knots or more. The main engines 5 have a large output and are large enough to extend beyond the deck 2, so the deck 2, which serves as the ceiling only for the engine room 15, is raised high. Since the two main engines 5 are placed across the entire width of the main hull 10, the main hull 10 becomes heavy and unstable, so side floats 20, 30 are provided to make the main hull a trimaran type to stabilize and obtain buoyancy. The wheelhouse 17 is located in the middle to reduce tonnage, and only has space for a person to stand.

[0015] In Fig. 2B, the bottom of the main hull 10 has a straight V shape on the bow B side, but is deformed to have a bottom RS carved out in an upturned bow shape on the stern S side. The bottom RS comprises an ascending bottom 12 that gradually becomes shallower from the bottom 11 toward the stern S, a descending bottom 13 that gradually becomes deeper from the bottom BV toward the stern S following the ascending bottom 12, and a horizontally extending stern bottom 14 to which the rudder 7 is attached following the descending bottom 13. The bottom BV is the shallowest bottom, and the propeller 4 is arranged corresponding to this position.

[0016] FIG. 3A is a cross section at the boundary between the bottom 11 and the ascending bottom 12. FIG. 3B is a cross section at the bottom BV of the ascending bottom 12 and the descending bottom 13. The bottom BV is the shallowest, and the propeller 4 rotates at this position. FIG. 3C is a cross section at the stern bottom 14. The depth of the stern bottom 14 is shallower than the straight V-shaped bottom 11 at the bow B side. The ascending bottom 12, the descending bottom 13, and the stern bottom 14 form a bottom RS around the propeller 4 that is hollowed out in an upturned bow shape. This allows two large propellers 4 to be installed within the depth limit to comply with the regulations for ships less than 24 m long. In addition, the propeller 4 must be at least 20 cm away from the bottom of the ship in consideration of vibration, ship speed, etc., but the shape of the bottom of the ship makes it possible to place it 30 cm away from the propeller 4.

[0017] The bottom of the main hull 10 where the propellers 4 are located is generally shallower than other parts, including near the side of the ship. This is because the ship is equipped with two main engines 5 and has large propellers 4 arranged in parallel, with the rotational diameter of the propellers 4 being closer to the side of the ship.

[0018] Deep wedge sections 21 are provided on both sides of the stern bottom 14. The wedge sections 21 are provided as a continuation of the straight V-shape from the bow B. Because the wedge sections 21 are deeper than the stern bottom 14, the water current WP is sandwiched between the wedge sections 21 as shown in FIG. 3D, and flows downward in a collected state. In this way, the water current WP flows downward, improving propulsion (forward pushing force). In addition, the wake behind the stern S is less likely to rise to the sea surface, which helps to suppress waves generated at fishing ports and aquaculture rafts.

[0019] The rudder 7 extends to a position deeper than the propeller 4, and has a larger water current resistance than usual. As a result, the force acting on the rudder 7 due to the pressure of the water current increases, and the rudder swings left and right at a deeper position, improving steering. In addition, at the position of the bottom RS, even the shallowest stern bottom 14 is shallower than the side floats 20, 30, except for a part of the rising bottom 12 (the connection with the bottom 11).

[0020] In addition, when a keel KL is attached to the bottom of the side floats 20, 30 (in Figure 1A, the keel KL is attached to the bottom of the side floats 20, 30), the deep part of the keel KL shall be regarded as the bottom of the side floats 20, 30.

[0021] Fig. 4 shows 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 side view of the water flow at the bottom of the ship. Fig. 4A shows how the water flow WS pushed aside by the bow B enters between the main hull 10 and the side floats 20, 30 as the ship speed increases. The water flow WS sandwiched between the main hull 10 and the side floats 20, 30 is sucked into the propeller 4 of the shallower ship bottom BV, so the intrusion of air from the side is suppressed. The deeper the ship bottom of the side floats 20, 30 is, the more effective it is.

[0022] In Fig. 4B, since the ascending ship bottom 12 and the descending ship bottom 13 are provided, a downward force as shown by the arrow is generated in the water flow WP from the propeller 4, and the water flow WP flows downward (deeper direction) from the horizontal. Therefore, the wave-making resistance can be reduced by making the accelerated water flow horizontally or downward.

[0023] [Example 2] In the previous embodiment, the ship bottom RS on the stern S side was deformed into a shape hollowed out like an up-bow, but in this embodiment, taking into consideration ease of manufacture, the ship bottom RS is made flat across the entire width of the ship, with only the propeller 4 area recessed into an egg shape. In this embodiment, the same reference symbols are used for components corresponding to those in the previous embodiment.

[0024] A bottom view is shown in FIG. 5A. In the figure, the bottom RS of the main hull 10 has a flat-bottomed ascending bottom 12 that gradually becomes shallower as it goes to the stern S direction following the bottom 11, and a flat-bottomed stern bottom 14 that extends horizontally and to which the rudder 7 is attached following the ascending bottom 12. Instead of the descending bottom 13 of the previous embodiment, an egg-shaped depression 22 is provided across the ascending bottom 12 and the stern bottom 14, where the bottom BV near the propeller 4 is the shallowest. The depressions 22 are provided in correspondence with the propeller 4. FIG. 5B is a cross section at the boundary between the bottom 11 and the ascending bottom 12. FIG. 5C is a cross section at the bottom BV of the ascending bottom 12 and the descending bottom 13. The bottom BV is the shallowest, and the propeller 4 rotates at this position. Moreover, Fig. 5D is a cross section at the stern ship bottom 14. Fig. 5E is a cross section taken along line Y4-Y4 in Fig. 5A, and the shallow position of the egg-shaped depression 22 corresponds to the ship bottom BV.

[0025] The depth of the stern bottom 14 is shallower than the straight V-shaped bottom 11 at the bow B side. At the position of the bottom RS, except for a part of the rising bottom 12 (the connection with the bottom 11), it is shallower than the side floats 20, 30. Therefore, the water flow WP is sandwiched between the side floats 20, 30 as shown in FIG. 5F, and flows downward in a collected state. Although the effect is inferior to that of the wedge portion 21 in the previous embodiment, the propulsive performance is improved by the water flow WP flowing downward. In addition, the wake 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.

[0026] In addition, at the bottom of the ship BV, the ship's side is shallower than in the previous embodiment, but as the ship speed increases, the water flow WS pushed aside by the bow B is sucked into the propeller 4 of the shallower bottom of the ship BV, and the water flow WS sandwiched between the main hull 10 and the side floats 20, 30 is sucked in by the propeller 4, and the ingress of air from the ship's side is suppressed, thereby obtaining the effect shown in Figure 4A. [Explanation of symbols]

[0027] 1. Trimaran passenger ship 2 deck 4 Propellers 5 Main engine 6 Travel room 7. Rudder 8 Steering Gear 9 Propeller shaft 10 Main Hull 11. Bottom of the Ship 12 Bottom of the Ascending Ship 13 Bottom of descending ship 14 Stern bottom 15. Engine Room 16 Thruster 17 Wheelhouse 18 Folding ladder 19 Steering Room 21 Wedge section 20, 30 Side float 40, 50 connection part

Claims

1. The main hull at the transom stern, A pair of left and right side floats, each of which is a transom stern that is shorter and smaller in volume than the main hull, aligned with the stern of the main hull and arranged side by side on both sides of the main hull, and has a straight bottom from the front end to the rear end; A connection portion that connects the main hull and the pair of side floats at a distance; A deck covering the main hull and the pair of side floats, The bottom of the main hull is as deep as or deeper than the bottom of the pair of side floats from the bow to just before the propeller shaft, and the bow side is straight V-shaped until just before the propeller shaft protrudes outboard, The stern side is provided with a rising bottom section which is gradually shallower in the stern direction following the straight V-shaped bottom section, and a stern bottom section which extends horizontally and is shallower than the straight V-shaped bottom section. A shallowest vessel bottom is provided between the rising vessel bottom and the stern vessel bottom, and a propeller is disposed at this position; A trimaran passenger ship characterized in that the depth of the stern bottom is shallower than the bottoms of the side floats on both sides, the propeller rotates at the position of the bottom where the depth is shallowest, and the water flow sandwiched between the main hull and the pair of side floats is sucked into the propeller at the position of the bottom where the depth is shallowest.

2. 2. The trimaran passenger ship according to claim 1, wherein said rising ship bottom and said stern ship bottom are flat-bottom shaped across the entire width of the ship.

3. 2. The trimaran passenger ship of claim 1, wherein an egg-shaped depression is provided across the rising ship bottom and the stern ship bottom, and the egg-shaped depression is the shallowest ship bottom portion.

4. 2. The trimaran passenger ship of claim 1, wherein a descending ship bottom is provided between the ascending ship bottom and the stern ship bottom, the descending ship bottom being gradually deeper toward the stern, and the portion between the ascending ship bottom and the descending ship bottom is the shallowest ship bottom.

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