Ships

Abstract

To provide a vessel capable of improving propulsion performance of each method when a hull is propelled by a wind power propulsion unit and when the hull is propelled by a propeller.SOLUTION: A vessel 1 comprises: a propeller 12 that generates thrust for a hull 11; and a wind power propulsion unit 10 that propels the hull 11 by means of wind power. Thus, the vessel 1 can propel the hull 11 by the wind power propulsion unit 10 when wind is strong, and propel the hull 11 by the propeller 12 when wind is weak. The hull 11 is propelled toward a bow during machine traveling where the hull 11 is propelled by the propeller 12, and the hull 11 is propelled toward a stern during sailing where the hull 11 is propelled by the wind power propulsion unit 10. In this case, the vessel 1 can be structured so as to suit the machine traveling for propulsion of the vessel 1 toward the bow. The vessel 1 can be structured so as to suit the sailing for propulsion of the vessel 1 toward the stern.SELECTED DRAWING: Figure 3

Description

Technical Field

[0001] The present invention relates to a ship.

Background Art

[0002] In recent years, ships that generate thrust using renewable energy such as wind power are known for reducing GHG gases such as CO2. For example, the ship described in Patent Document 1 includes a wind propulsion unit that propels the hull by wind power on the hull in addition to a propeller-based propulsion device.

Prior Art Documents

Patent Documents

[0003]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0004] Here, when the hull is propelled by the wind propulsion unit and when the hull is propelled by the propulsion device, it has been required to improve the performance during propulsion by each method.

[0005] The present invention has been made to solve such problems, and an object thereof is to provide a ship capable of improving the performance during propulsion by each method when the hull is propelled by the wind propulsion unit and when the hull is propelled by the propulsion device.

Means for Solving the Problems

[0006] The ship according to the present invention includes a hull, a propulsion device that generates thrust of the hull, and a wind propulsion unit that propels the hull by wind power. When the hull is propelled by the propulsion device, the hull propels in the bow direction, and when the hull is propelled by the wind propulsion unit, the hull propels in the stern direction.

[0007] A ship is equipped with a propeller that generates thrust for the hull and a wind-powered propulsion unit that propels the hull using wind power. Therefore, when the wind is strong, the ship can sail, propelling itself using the wind-powered propulsion unit, and when the wind is weak, it can run on engine power, propelling itself using the propeller. When the ship is running on engine power, propelled by the propeller, it moves in the bow direction, and when the ship is sailing, propelled by the wind-powered propulsion unit, it moves in the stern direction. In this case, the ship can be designed to be suitable for engine propulsion when propelling it in the bow direction, and for sailing when propelling it in the stern direction. Thus, the performance of each propulsion method can be improved, whether the ship is propelled by the wind-powered propulsion unit or by the propeller.

[0008] A ship is equipped with a regenerative unit that performs regeneration (recovery of electricity) when the hull is propelled by a wind power propulsion unit, and the regenerative unit may be located at the stern. In this case, when the hull is propelled sternward by sailing, the regenerative unit can efficiently perform regeneration at a high flow velocity in an upstream position in the water flow.

[0009] An azimuth thruster may be provided as a propulsion system. Since the azimuth thruster can be rotated 180° in place, the direction of the thruster can be easily switched between motor-driven and sail-driven operation by rotating it 180°.

[0010] When the hull is propelled by the wind power unit, regeneration may be performed using the azimuth thrusters. In this case, the azimuth thrusters are used for engine propulsion, and in the case of sailing, the direction of the azimuth thrusters can be rotated 180° to perform regeneration in place.

[0011] The hull may have living quarters, and these quarters may have a flow-straightening structure that straightens the airflow towards the wind propulsion section. In this case, turbulence in the airflow within the living quarters can be suppressed, allowing the air to flow smoothly to the wind propulsion section.

[0012] The hull may have a flow straightening section located aft of the living quarters to straighten the airflow from the stern towards the bow. In this case, it is possible to suppress the turbulence of the wind at the stern and the resulting resistance during sailing. [Effects of the Invention]

[0013] According to the present invention, it is possible to provide a vessel that can improve the performance of each propulsion method, whether the vessel is propelled by a wind power propulsion unit or by a propeller. [Brief explanation of the drawing]

[0014] [Figure 1] This is a schematic cross-sectional view showing an example of a ship according to an embodiment of the present invention. [Figure 2] (a) is a diagram illustrating the principle of a rotor sail, and (b) is a plan view of a ship. [Figure 3] This is a schematic side view of the stern structure of a ship. [Figure 4] This diagram conceptually illustrates the effect of the rectifier. [Figure 5] This diagram conceptually illustrates the effect of the airflow rectification structure in the residential area. [Figure 6] This is an enlarged side view showing the propulsion system of a modified vessel. [Figure 7] This is a diagram showing a modified vessel. [Figure 8] This diagram shows the wind propulsion system of a modified vessel. [Modes for carrying out the invention]

[0015] Preferred embodiments of the present invention will be described below with reference to the drawings. In the following description, the terms "front" and "rear" correspond to the direction of travel of the hull, the term "side" corresponds to the left-right (width) direction of the hull, and the terms "up" and "down" correspond to the up-down direction of the hull.

[0016] FIG. 1 is a schematic cross-sectional view showing an example of a ship according to an embodiment of the present invention. The ship 1 is a ship that transports petroleum-based liquid cargo such as crude oil and liquefied gas, for example, an oil tanker. Note that the ship is not limited to an oil tanker, and may be, for example, a bulk carrier, a car carrier, or various other types of ships.

[0017] As shown in FIG. 1, the ship 1 includes a hull 11, a propeller 12, and a plurality of wind propulsion units 10. The hull 11 has a bow 2, a stern 3, an engine room 4, and a cargo hold 6. An upper deck 19 is provided on the upper part (or inside) of the hull 11. The bow 2 is located on the front side of the hull 11. The stern 3 is located on the rear side of the hull 11.

[0018] The bow 2 has a shape designed to reduce wave-making resistance in, for example, a fully loaded draft condition. The propeller 12 mechanically generates thrust for the hull 11, and for example, a screw propeller is used. This screw propeller may have a variable pitch mechanism. The propeller 12 is installed below the waterline of the seawater W at the stern 3 during propulsion. Further, below the waterline at the stern 3, an azimuth thruster 15 that also functions as a rudder for adjusting the propulsion direction is installed. The azimuth thruster 15 can rotate 180°. For example, it is possible to switch between a state where the propeller 12 is arranged on the bow side as shown in FIG. 1 and a state where the propeller 12 is arranged on the stern side as shown in FIG. 3. Thus, the azimuth thruster 15 is provided at a position near the end on the stern side of the hull 11.

[0019] The engine room 4 is provided at a position adjacent to the bow side of the stern part 3. The engine room 4 is a compartment for arranging the main engine. On the upper deck 19, a living area 22 and a chimney 23 for exhaust are provided above the engine room 4. The cargo hold 6 is provided between the bow part 2 and the engine room 4. The cargo hold 6 is a compartment for accommodating petroleum-based cargo. The cargo hold 6 is partitioned into a cargo oil tank 26 and a plurality of ballast tanks 27 by adopting a double hull structure of the outer plate 20 and the inner bottom plate 21. The cargo oil tank 26 loads the petroleum-based cargo transported by the ship 1. The ballast tank 27 accommodates a quantity of ballast water according to the size of the ship and the like.

[0020] The wind propulsion unit 10 is a mechanism for propelling the hull 11 by wind power. In the present embodiment, a rotor-type wind propulsion mechanism is adopted as the wind propulsion unit 10. A plurality (here, four) of wind propulsion units 10 are provided on the upper deck 19 of the hull 11 so as to be arranged in the front-rear direction. As shown in Fig. 2(a), the wind propulsion unit 10 includes a columnar rotor sail 31 extending in the vertical direction and an electric motor 32 for rotating the rotor sail 31. When the wind WD blows in from the side of the rotor sail 31, the rotational direction of the rotor sail 31 and the direction of the wind WD are opposite to each other on the bow side, and the rotational direction of the rotor sail 31 and the direction of the wind WD are the same on the stern side. As a result, a pressure difference occurs before and after the rotor sail 31, thereby generating a thrust PF toward the stern side (Magnus effect). As shown in Fig. 2(b), when the wind WD blows from the side of the hull 11, the hull 11 advances toward the stern side by the thrust PF of each wind propulsion unit 10. As shown in Fig. 1, the rotor sail 31, which is the wind propulsion unit 10, may be provided on the wall of the cargo hold 6. Thereby, even when supporting a structure with a large weight such as the rotor sail 31, it can serve as a reinforcing member for supporting the rotor sail by being provided on the wall of the cargo hold 6.

[0021] Here, when the hull 11 is propelled by the thruster 12 (motorized mode), the hull 11 is propelled in the direction FD (direction forward) towards the bow. At this time, the direction of the propeller of the azimuth thruster 15 is as shown in Figure 1. Motorized mode is executed when the wind speed is below a predetermined level and sufficient thrust cannot be obtained from the wind propulsion unit 10. In motorized mode, the bow section 2 is the upstream part in the direction FD. Therefore, the bow section 2 is designed to be suitable for motorized mode. The bow section 2 has a shape that reduces fluid resistance caused by wave generation at the bow and has a structure that straightens the airflow so as little air resistance as possible against wind coming from the front.

[0022] On the other hand, when the hull 11 is propelled by the wind power unit 10 (sailing mode), the hull 11 is propelled in the direction of travel BD towards the stern. At this time, the direction of the propeller of the azimuth thruster 15 is as shown in Figure 3. Sailing mode is performed when the wind speed is above a predetermined level and sufficient thrust can be obtained from the wind power unit 10. In sailing mode, the stern section 3 is the upstream part in the direction of travel BD. Therefore, the stern section 3 is designed to be suitable for sailing mode. The stern section 3 has a structure that straightens the airflow so as to minimize air resistance against wind coming from the rear.

[0023] Specifically, the hull 11 has a flow straightening section 30 located aft of the living quarters 22, which straightens the airflow from the aft to the bow. The flow straightening section 30 is located higher than the upper deck 19 and further aft than the living quarters 22. The flow straightening section 30 has an inclined surface that gradually rises in height from the aft to the bow. At the aft end, the inclined surface of the flow straightening section 30 is at the height of the upper deck 19, and at the bow end, it is at the height near the top of the living quarters 22.

[0024] For example, as shown in Figure 4(a), if a flow straightening section 30 is not provided on the stern side of the living quarters 22, when the vessel is propelled in the stern direction BD, the wind WD1 directly collides with the hull 11 and living quarters 22, resulting in increased resistance. In contrast, as shown in Figure 4(b), if a flow straightening section 30 is provided on the hull 11, when the vessel is propelled in the stern direction BD, the wind WD1 flows along the shape of the inclined surface of the flow straightening section 30, thereby reducing resistance. Note that the flow straightening section 30 may be omitted, and a structure like that shown in Figure 4(a) can also be adopted.

[0025] The living quarters 22 may have a flow straightening structure 40 that straightens the wind flowing toward the wind propulsion unit 10. The flow straightening structure 40 is formed by chamfering or rounding the corners of the living quarters 22 when viewed from above. For example, as shown in Figure 5(a), if the living quarters 22 does not have a flow straightening structure 40, when wind WD2 flows diagonally forward toward the hull 11 and wind WD3 flows diagonally backward toward the hull 11, vortices will be created as the wind collides with the corners of the living quarters 22. In this case, it becomes difficult for the wind to enter the wind propulsion unit 10. In contrast, as shown in Figure 5(b), if the living quarters 22 has a flow straightening structure 40, when wind WD2 flows diagonally forward toward the hull 11 and wind WD3 flows diagonally backward toward the hull 11, the flow straightening structure 40 at the corners of the living quarters 22 straightens the wind, suppressing the generation of vortices. Therefore, the wind can enter the wind propulsion unit 10 smoothly. Figure 5 shows, with dashed lines, a configuration in which the wind power propulsion unit 10 is located further forward than the living quarters 22, as will be explained in the modified configuration described later. The rectified winds WD2 and WD3 smoothly enter the wind power propulsion units 10 on the forward and aft sides of the living quarters 22.

[0026] As shown in Figure 3, when the hull is propelled sternward in the direction of travel BD by the wind propulsion unit 10, the vessel 1 regenerates energy using the azimuth thruster 15. In this state, the thruster 12 of the azimuth thruster 15 is positioned at the stern end of the hull 11, i.e., at the very front in the direction of travel BD, with the thruster 12 facing sternward. Therefore, the water flow WF flowing relative to the hull 11 in the direction of travel BD flows efficiently to the thruster 12 of the azimuth thruster 15. With this structure, the azimuth thruster 15 functions as a regenerative unit 50 that regenerates energy when the hull 11 is propelled by the wind propulsion unit 10. In this case, the regenerative unit 50 is located at the stern. The regenerated energy may be used to rotate the rotor sail 31 of the wind propulsion unit 10, or it may be stored. If the wind power is insufficient for propulsion by sailing alone, the azimuth thruster 15 generates thrust by rotating.

[0027] Next, the operation and effects of the vessel 1 according to this embodiment will be described.

[0028] The vessel 1 is equipped with a propeller 12 that generates thrust for the hull 11 and a wind-powered propulsion unit 10 that propels the hull 11 using wind power. Therefore, when the wind is strong, the vessel 1 can propel the hull 11 using the wind-powered propulsion unit 10, and when the wind is weak, it can propel the hull 11 using the propeller 12.

[0029] Here, when sailing, the hull 11 tilts or turns due to the influence of the point of force application and direction of the wind force acting on the sails, so the suitable hull shape may differ from that when running under engine power. If a single vessel 1 can have different hull and deck structure shapes to suit both sailing and engine running, it will be possible to achieve good performance in either mode of operation.

[0030] Therefore, in this embodiment, when the hull 11 is propelled by the propeller 12, the hull 11 is propelled in the bow direction, and when the hull 11 is propelled by the wind propulsion unit 10, the hull 11 is propelled in the stern direction. In this case, for propulsion in the bow direction of the vessel 1, the vessel 1 can be made into a structure suitable for propulsion by engines. For example, the bow side of the hull 11 can be made into a hull structure suitable for propulsion by engines. Also, the propeller 12 can be placed on the stern side. Furthermore, for propulsion in the stern direction of the vessel 1, the vessel 1 can be made into a structure suitable for sailing. For example, the stern side of the hull 11 can be made into a hull structure suitable for sailing. Also, the propeller 12, which functions as a regenerative unit 50, can be placed at the very front of the water flow. As described above, the performance of each propulsion method can be improved, whether the hull 11 is propelled by the wind propulsion unit 10 or by the propeller 12. If the thruster 12 (screw propeller) is of a variable pitch type, the regenerative efficiency could potentially be further improved by appropriately adjusting the pitch angle.

[0031] The vessel 1 is equipped with a regenerative unit 50 that performs regeneration when the hull 11 is propelled by the wind propulsion unit 10, and the regenerative unit 50 may be located at the stern. In this case, when the hull 11 is propelled sternward by sailing, the regenerative unit 50 can efficiently perform regeneration at a high flow velocity at an upstream position in the water flow.

[0032] The propulsion system 12 may be equipped with an azimuth propulsion system 15. Since the azimuth propulsion system 15 can be rotated 180° in place, the direction of the propulsion system 12 can be easily switched between motor-driven and sail-driven operation by rotating it 180°.

[0033] When the hull 11 is propelled by the wind power propulsion unit 10, regeneration may be performed with the azimuth thruster 15. In this case, the azimuth thruster 15 is used for motor propulsion, and in the case of sailing, the direction of the azimuth thruster 15 can be rotated 180° to perform regeneration in place. Even when the azimuth thruster 15 is rotated 180° and used for regeneration in sailing mode, if the wind power is temporarily insufficient, the propulsion force can be supplemented by driving the propeller.

[0034] The hull 11 has a living quarters 22, and the living quarters 22 may have a flow straightening structure 40 that straightens the airflow toward the wind propulsion unit 10. In this case, turbulence of the airflow in the living quarters 22 is suppressed, and the airflow toward the wind propulsion unit 10 can be directed smoothly.

[0035] The hull 11 may have a flow straightening section 30 located aft of the living quarters 22, which straightens the airflow from the aft to the bow. In this case, it is possible to suppress the generation of wind turbulence and resistance at the aft during sailing.

[0036] As in this embodiment, in power generation using rotor blades (propeller 12), installing the rotor blades in a location with the highest possible flow velocity increases the amount of power generated and improves operational efficiency. In the flow velocity along the side of the hull 11, the frontmost point relative to the direction of travel has the highest flow velocity, and the flow velocity decreases towards the rear due to friction between the hull 11 and the water (due to wake). Therefore, installing the rotor blades for power generation at the frontmost point relative to the direction of travel is the most efficient for power generation. However, when the rotor blades are not generating power, they create significant resistance in a fast flow, impairing the propulsion performance of the ship 1, so it is desirable for them to be in a slow flow. Generally, when the motor-propelled propeller is installed in a slow flow (wake) at the stern, the propulsion efficiency (fuel efficiency) improves. When the motor-propelled propeller is of the rotor blade type, it can also function as a power-generating rotor blade. According to this embodiment, when motor-driven, the power-generating rotor blade (which may also function as a motor-propelled propeller) can be placed at the stern where the flow velocity is slow, and when sailing, the power-generating rotor blade can be placed at the frontmost point on the forward side where the flow velocity is high. By using the azimuth thruster 15 as the propulsion system, not only can the power-generating rotor blades be placed at the very front of the forward-moving side, but they also serve as rudder blades, thus enabling the above performance to be secured even more efficiently.

[0037] The present invention is not limited to the embodiments described above.

[0038] For example, as shown in Figure 6(a), a contra-rotating propeller can be adopted by positioning a conventional thruster 13 driven by the main engine opposite the thruster 12 of the azimuth thruster 15. When sailing, as shown in Figure 6(b), the azimuth thruster 15 can be rotated 180° and the rotation of the front thruster 13 can be stopped. Alternatively, a twin-headed azimuth thruster can be used. In this case, it is not necessary to rotate the direction of the thruster 180° according to the direction of travel, as is the case with the azimuth thruster 15.

[0039] Furthermore, there are no particular limitations on the number or arrangement of the wind propulsion units, or how they are installed on the hull. For example, as shown in Figure 7(a), a wind propulsion unit 10 may also be installed on the stern side of the living quarters 22. Here, as shown in Figure 7(b), in a wind propulsion unit 10 with a rotor sail, the blind spot DV when looking in the direction of travel FD,BD from the navigation bridge 22a on the top floor of the living quarters is narrower compared to other sails. Therefore, when a wind propulsion unit 10 is installed on the stern side, as in the configuration shown in Figure 7, it is preferable to use one with a rotor sail.

[0040] The wind propulsion unit 10 is not limited to a rotor sail, but is not particularly limited to any other type of sail that can propel the hull by wind power, such as a regular sail or a kite. For example, the wind propulsion unit 10 may be a cloth sail as shown in Figures 8(a) and 8(b), a steel sail as shown in Figure 8(c), or a kite as shown in Figure 8(d).

[0041] The structure of the hull 11 is not limited to that shown in Figure 1, and may be modified as appropriate depending on the intended use.

[0042] [Form 1] The hull and, A propulsion system that generates thrust for the hull, It comprises a wind power propulsion unit that propels the hull using wind power, When the hull is propelled by the propeller, the hull is propelled in the bow direction. A vessel in which, when the hull is propelled by the aforementioned wind power propulsion unit, the hull is propelled in the stern direction. [Form 2] The vessel is equipped with a regenerative unit that performs regeneration when the hull is propelled by the wind power propulsion unit, The regenerative unit is located on the stern side of the vessel according to the configuration 1. [Form 3] The vessel according to form 1 or 2, wherein the propulsion system is an azimuth propulsion system. [Form 4] The vessel according to Embodiment 3, wherein when the hull is propelled by the wind power propulsion unit, regeneration is performed by the azimuth propulsion unit. [Form 5] The hull has a living quarters, The vessel according to any one of the forms 1 to 4, wherein the living quarters have a flow straightening structure that straightens the airflow toward the wind propulsion unit. [Form 6] The vessel according to any one of the embodiments 1 to 5, wherein the hull has a flow straightening section provided on the stern side relative to the living quarters and which straightens the airflow from the stern side toward the bow side. [Explanation of symbols]

[0043] 1...ship, 11...hull, 10...wind propulsion unit, 12...propeller, 15...azimuth propulsion unit, 22...accommodation area, 30...rectification unit, 40...rectification structure, 50...regeneration unit.

Claims

1. The hull and, A propulsion system that generates thrust for the hull, It comprises a wind power propulsion unit that propels the hull using wind power, When the hull is propelled by the propeller, the hull is propelled in the bow direction. When the hull is propelled by the wind power propulsion unit, the hull is propelled in the stern direction, and the propeller performs regeneration. A ship in which, when the hull is propelled in the bow direction by the propulsion system, the propeller of the propulsion system faces in the bow direction, and when the hull is propelled in the stern direction by the wind power propulsion system, the propeller of the propulsion system faces in the stern direction.

2. The hull has a living quarters located at the stern, Multiple wind power propulsion units are provided, The vessel according to claim 1, wherein at least one of the wind propulsion units is located sternward from the living quarters.

3. The vessel according to claim 2, wherein the wind propulsion unit located sternward from the living quarters is a rotor sail.

4. The vessel according to any one of claims 1 to 3, wherein the propulsion system is an azimuth propulsion system.

5. The vessel according to claim 4, wherein when the hull is propelled by the wind power propulsion unit, regeneration is performed by the azimuth propulsion unit.

Images