Air-lubricated ship

Abstract

An air-lubricated ship, comprising a hull (10), an air lubrication device (40) and an air venting device (30). The air lubrication device (40) is configured to form an air lubrication layer on the bottom surface of the hull (10), and an air outlet (19) is formed in the end of the bottom surface of the hull (10) close to a stern (15). The air venting device (30) comprises an air venting cavity (39) and an exhaust channel (32), wherein the air venting cavity (39) is arranged in the hull (10), the air venting cavity (39) is communicated with the air outlet (19), the exhaust channel (32) is arranged in the hull (10), and the exhaust channel (32) has one end communicated with the air venting cavity (39) and the other end passing through a deck (16) of the hull (10). The ship can prevent bubbles from being drawn into a propeller area, thereby avoiding thrust reduction.

Description

Air layer drag reduction ship

[0001] The present application claims priority to the Chinese patent application No. 2024107989668 filed on June 20, 2024 with the China Patent Office, the content of which is incorporated herein by reference in its entirety. TECHNICAL FIELD

[0002] The present application relates to the technical field of air layer drag reduction for ships, for example to an air layer drag reduction ship. BACKGROUND

[0003] Air layer drag reduction technology for ships refers to a technology that forms and maintains an air layer on the bottom of a ship by specially designed devices to ventilate the bottom of the ship, so as to isolate the ship bottom surface from water and reduce the wet surface area, thereby significantly reducing the ship drag and fuel consumption. The mechanism and position of this technology are different from those of other mature energy-saving devices, so it can be used in combination with other energy-saving devices and is a new type of ship energy-saving and emission-reducing technology with great potential.

[0004] During the forward movement of the ship, the air layer on the ship bottom moves towards the stern. Due to the suction effect of the propeller, the air may be sucked into the propeller area, reducing the propeller thrust.

[0005] SUMMARY

[0006] The present application provides an air layer drag reduction ship, which can avoid the air flow on the ship bottom being sucked into the propeller area and reducing the propeller thrust without increasing the ship movement resistance.

[0007] The present application provides an air layer drag reduction ship, which includes a ship body and an air layer drag reduction device, the air layer drag reduction device is arranged on the ship body and is configured to form a drag reduction air layer on the bottom surface of the ship body, and the bottom surface of the ship body is provided with a gas discharge port at one end close to the stern.

[0008] The air layer drag reduction ship further includes a gas discharge device, and the gas discharge device includes:

[0009] A gas discharge cavity is arranged in the ship body, and the gas discharge cavity is in communication with the gas discharge port.

[0010] An exhaust passage is arranged in the ship body, one end of the exhaust passage is in communication with the gas discharge cavity, and the other end penetrates through the deck of the ship body.

[0011] As an optional solution of the above air layer drag reduction ship, the ship body includes:

[0012] A ship bottom plate;

[0013] A skirt plate is arranged on the outer wall of the ship bottom plate and connected end to end to enclose an air chamber.

[0014] A wedge-shaped flow guide is arranged on the outer wall of the bottom plate and located at one end of the air cavity close to the stern, the wedge-shaped flow guide extends along the width direction of the ship body, and the wedge-shaped surface of the wedge-shaped flow guide is arranged towards the bow.

[0015] As an optional solution of the air layer drag reduction ship, at least one end of the wedge-shaped flow guide along the width direction of the ship body is arranged to form a gas gap with the apron, the gas gap is located outside the air cavity, and the gas gap is arranged close to the gas gap.

[0016] As an optional solution of the air layer drag reduction ship, the ship body includes a bottom plate and an inner bottom plate located above the bottom plate, the gas cavity is formed between the bottom plate and the inner bottom plate, and the gas outlet is arranged on the bottom plate.

[0017] As an optional solution of the air layer drag reduction ship, the gas purging device further includes a gas purging tank, the gas purging tank is arranged between the bottom plate and the inner bottom plate, and the gas purging tank and the bottom plate form the gas cavity.

[0018] As an optional solution of the air layer drag reduction ship, the exhaust passage is in communication with the top of the gas cavity.

[0019] As an optional solution of the air layer drag reduction ship, the gas outlet is provided with a gas permeable grille.

[0020] As an optional solution of the air layer drag reduction ship, the gas purging device further includes a gas blowing pipe, one end of the gas blowing pipe is arranged in communication with a gas source, and the other end is located in the gas cavity and faces the gas permeable grille.

[0021] As an optional solution of the air layer drag reduction ship, an anti-seawater biological electrode is arranged on the inner wall of the gas cavity.

[0022] And / or, a sacrificial anode protection device is arranged on the inner wall of the gas cavity.

[0023] As an optional solution of the air layer drag reduction ship, a sand leakage hole in communication with the gas cavity is arranged on the bottom surface of the ship body. BRIEF DESCRIPTION OF DRAWINGS

[0024] Fig. 1 is a sectional view of the air layer drag reduction ship provided by the present application;

[0025] Fig. 2 is a bottom view of the air layer drag reduction ship provided by the present application;

[0026] Fig. 3 is a partial structure schematic view of the air layer drag reduction ship provided by the present application;

[0027] Fig. 4 is a structural schematic diagram of a gas purging device provided by the present application.

[0028] In the drawings:

[0029] 10, hull; 11, bottom plate; 111, sand leakage hole; 12, inner bottom plate; 13, skirt plate; 14, wedge-shaped flow guide; 15, stern; 16, deck; 17, bow; 18, air pocket; 19, gas purging port; 20, propeller; 30, gas purging device; 31, gas purging tank; 32, exhaust passage; 33, on-off valve; 34, air permeable grille; 35, anti-marine-bio electrode; 36, sacrificial anode protection device; 37, air blowing pipe; 38, pipe joint; 39, gas purging cavity; 40, air layer drag reduction device; 41, pressure stabilizing cavity; 43, gas purging gap. DETAILED DESCRIPTION

[0030] The present application will be described in detail below with reference to the drawings and embodiments. The embodiments described herein are merely intended to explain the present application, but not to limit the present application. For the purpose of description, only parts related to the present application are shown in the drawings, but not all structures.

[0031] In the description of the present application, unless otherwise specified and limited, the terms "connected", "connected", "fixed" should be understood broadly, for example, can be fixedly connected, or can be detachably connected, or can be integrated; can be mechanically connected, or can be electrically connected; can be directly connected, or can be indirectly connected through an intermediate medium, or can be the internal communication of two elements or the interaction relationship between two elements. The meaning of the above terms in the present application can be understood according to the actual situation.

[0032] In the present application, unless otherwise specified and limited, the "upper" or "lower" of the first feature to the second feature can include that the first feature and the second feature are in direct contact, or can include that the first feature and the second feature are not in direct contact but are in contact through another feature between them. Moreover, the "upper", "above" and "on" of the first feature to the second feature includes that the first feature is directly above and obliquely above the second feature, or only indicates that the horizontal height of the first feature is higher than that of the second feature. The "below", "under" and "under" of the first feature to the second feature includes that the first feature is directly below and obliquely below the second feature, or only indicates that the horizontal height of the first feature is less than that of the second feature.

[0033] In the description of the present embodiment, the terms "upper", "lower", "right", and other orientation or position relationship are based on the orientation or position relationship shown in the drawings, which is only for the purpose of description and simplification of operation, and does not indicate or imply that the device or element referred to must have a particular orientation, be constructed and operated in a particular orientation, and therefore cannot be understood as a limitation on the present application. In addition, the terms "first" and "second" are only used to distinguish in the description, and have no special meaning.

[0034] As shown in FIG. 1 and 2, the embodiment provides a gas layer drag reduction ship, which includes a ship body 10, a propeller 20 and a gas layer drag reduction device 40. The gas layer drag reduction device 40 is arranged on the ship body 10 and is configured to form a drag reduction gas layer on the bottom surface of the ship body 10. The gas layer drag reduction device 40 can form a gas layer on the bottom surface of the ship body 10, isolate the bottom surface of the ship body 10 from water through the gas layer, reduce the wet surface area, and significantly reduce the ship drag and fuel consumption. The propeller 20 is arranged at the stern of the ship body 10 and can rotate under the drive of a power device to provide power for the movement of the ship.

[0035] As shown in FIG. 2, the gas layer drag reduction device 40 includes a pressure stabilizing cavity 41 arranged at the bottom of the ship body 10. The pressure stabilizing cavity 41 is communicated with a gas injection hole. The pressure stabilizing cavity 41 is configured to be connected to a gas source. After the gas flow provided by the gas source enters the pressure stabilizing cavity 41, the gas flow is stably flowed to the bottom of the ship body 10 through the gas injection hole to form and maintain a drag reduction gas layer on the bottom surface of the ship body 10.

[0036] Optionally, a plurality of pressure stabilizing cavities 41 can be arranged. The plurality of pressure stabilizing cavities 41 are arranged at intervals along the length direction (X direction in FIG. 2) of the ship body 10. Each pressure stabilizing cavity 41 is a long strip structure extending along the width direction (Y direction in FIG. 2) of the ship body 10. This arrangement can increase the gas injection position of the gas layer drag reduction device 40, and make the gas flow on the bottom of the ship body 10 uniformly distributed, which is conducive to maintaining a stable drag reduction gas layer.

[0037] To avoid the diffusion of the gas flow on the ship bottom causing the instability of the gas layer, the ship body 10 includes a ship bottom plate 11 and a skirt plate 13 arranged on the outer wall of the ship bottom plate 11. The skirt plate 13 is connected at the head and tail to form an air pocket. The pressure stabilizing cavity 41 is located in the area surrounded by the air pocket. The air pocket formed by the skirt plate 13 is conducive to the gas flow injected from the gas injection hole to gather in the air pocket, slow down the diffusion of the gas layer, and is conducive to maintaining the stability of the drag reduction gas layer.

[0038] During the forward movement of the ship, the gas layer on the bottom of the ship body 10 moves towards the stern of the ship body 10. Since the propeller 20 is arranged at the stern of the ship body 10, the gas may be sucked into the propeller area under the action of the propeller 20, which reduces the thrust of the propeller 20.

[0039] To avoid such a situation, the ship in the embodiment further includes a gas dredging device 30. The gas dredging device 30 can guide the gas flow on the bottom of the ship body 10 close to the stern to a designated position, thereby reducing the gas flow sucked by the propeller 20, improving the thrust of the propeller 20, and increasing the efficiency of the gas layer drag reduction device 40.

[0040] In one or more embodiments, a vent 19 is provided on the bottom surface of the hull 10 near the stern 15. The gas drainage device 30 includes a venting chamber 39 and an exhaust channel 32. The venting chamber 39 is located inside the hull 10 and communicates with the vent 19. The exhaust channel 32 is located inside the hull 10, with one end communicating with the venting chamber 39 and the other end passing through the deck 16 of the hull 10. By providing the gas drainage device 30, the overflow gas in the drag-reducing gas layer at the stern end of the hull 10 is diverted, allowing this portion of the overflow gas to pass through the vent 19, the venting chamber 39, and the exhaust channel 32, and then be discharged onto the deck 16. This prevents the overflow gas from entering the propeller area and affecting the performance of the propeller 20, thereby increasing the overall energy-saving and drag-reducing effect of the gas layer drag-reducing device 40.

[0041] In this embodiment, both the venting cavity 39 and the exhaust channel 32 are located inside the hull 10, without adding any accessories to the outer wall of the hull 10, and without increasing the resistance experienced by the hull 10 during navigation, thereby avoiding affecting the energy-saving and drag-reducing effect of the drag-reducing air layer.

[0042] To prevent airflow towards the propeller 20, a wedge-shaped guide 14 is provided on the outer wall of the bottom plate 11. The wedge-shaped guide 14 is located within the air cavity 18 near the stern 15, extending along the width of the hull 10, with its wedge-shaped surface facing the bow 17. By providing the wedge-shaped guide 14, the airflow towards the stern 15 can be blocked to a certain extent, thereby preventing the airflow from being drawn into the area of ​​the propeller 20.

[0043] At least one end of the wedge-shaped guide 14 along the width direction of the hull 10 is spaced apart from the skirt 13 to form an air venting gap 43.

[0044] In order to improve the drainage effect of the overflow airflow and avoid affecting the stability of the air layer, the wedge-shaped guide 14 is provided at both ends of the hull 10 and the skirt 13 at intervals to form a venting gap 43. The venting port 19 is located outside the air cavity 18 and is located close to the venting gap 43.

[0045] When the drag-reducing gas layer device 40 continuously injects gas below the bottom plate 11, the gas flows towards the stern, passing over the wedge-shaped guide 14. At this time, the overflowing airflow will concentrate and flow out from the vent gaps 43 at both ends of the wedge-shaped guide 14, resulting in a relatively concentrated overflow area. By placing the vent 19 outside the air cavity 18 and close to the vent gap 43, the overflowing airflow can easily enter the vent chamber 39 through the vent 19, and then be discharged to the top of the deck 16 through the exhaust channel 32. This avoids the overflowing airflow affecting the propeller 20 and also avoids affecting the stability of the drag-reducing gas layer by setting up the vent 19.

[0046] As shown in Figure 2, the vent 19 can be located on the side of the wedge-shaped guide 14 near the stern 15, so that the overflow airflow flowing toward the stern 15 can pass through the vent 19.

[0047] As shown in Figure 2, the width of the air cavity 18 gradually decreases near the stern 15. The wedge-shaped guide 14 is located at the end of the air cavity 18 near the stern 15, which helps to concentrate the overflow area of ​​the airflow, thereby improving the guiding effect of the gas venting device 30 on the overflow airflow.

[0048] By using experimental or numerical calculation methods, the coverage area and direction of the gas overflow from both ends of the wedge-shaped guide 14 can be determined. The position and size of the vent 19 can be designed according to the coverage area and direction, which can improve the dredging effect of the overflowing airflow.

[0049] As shown in Figure 3, the venting chambers 39 located at both ends of the wedge-shaped guide 14 can be positioned near the port side and near the starboard side of the hull 10, respectively. The exhaust channel 32 can extend upward from the venting chambers 39 along the space on both sides of the hull 10 to the deck 16 to avoid interfering with other structures within the hull 10.

[0050] The bottom plate 11 at the vent 19 has an upward curvature, which can guide the overflowing airflow to the left and right sides of the hull 10, and prevent the overflowing airflow that does not enter the vent 19 from being sucked up by the propeller 20.

[0051] Optionally, a switch valve 33 may be provided at one end of the exhaust passage 32 that extends outside the deck 16. The switch valve 33 is configured to control the connection and disconnection between the exhaust passage 32 and the outside, so as to close the exhaust passage 32 when exhaust is not required, thereby preventing the exhaust passage 32 from becoming blocked.

[0052] In this embodiment, the hull 10 also includes an inner bottom plate 12 located above the bottom plate 11. A venting cavity 39 is formed in the space between the bottom plate 11 and the inner bottom plate 12, and a vent 19 is disposed on the bottom plate 11. By placing the venting cavity 39 between the inner bottom plate 12 and the bottom plate 11, the internal space of the hull 10 can be utilized in a reasonable manner.

[0053] As shown in Figure 4, the gas venting device 30 also includes a venting box 31, which is disposed between the bottom plate 11 and the inner bottom plate 12. The venting box 31 covers the inner wall of the bottom plate 11, so that the venting box 31 and the bottom plate 11 form a venting cavity 39. Optionally, a sealing element can be provided between the venting box 31 and the bottom plate 11 to seal the assembly gap between the venting box 31 and the bottom plate 11, preventing gas or seawater entering the venting cavity 39 through the venting port 19 from entering the cavity between the inner bottom plate 12 and the bottom plate 11.

[0054] Since the vent 19 is located on the bottom plate 11, seawater inevitably enters the vent chamber 39 through the vent 19. To prevent seawater from entering the exhaust channel 32, the exhaust channel 32 is connected to the top of the vent chamber 39. As shown in Figure 4, the top of the vent box 31 is provided with a pipe connector 38, which is configured to connect to the exhaust channel 32.

[0055] To prevent impurities such as silt or organisms in the seawater from entering the ventilation chamber 39 through the ventilation port 19, a ventilation grille 34 is installed inside the ventilation port 19. The ventilation grille 34 includes multiple horizontally and vertically intersecting bars to form a mesh structure, which can filter and block impurities or organisms from entering the ventilation chamber 39.

[0056] To prevent impurities such as mud and sand from clogging the ventilation grille 34, the gas venting device 30 also includes an air blowing pipe 37. One end of the air blowing pipe 37 is connected to an air source, and the other end is located inside the venting chamber 39 and faces the ventilation grille 34. By setting the air blowing pipe 37, air can be blown onto the ventilation grille 34, thereby blowing off the impurities such as mud and sand attached to the ventilation grille 34, effectively cleaning the ventilation grille 34, preventing clogging, and ensuring the effective venting of overflowing airflow.

[0057] Optionally, the air blowing pipe 37 includes two pipe sections arranged at an angle. For ease of explanation, along the airflow direction inside the air blowing pipe 37, the two pipe sections are respectively the first pipe section and the second pipe section. The air blowing pipe 37 can rotate around the axis of the first pipe section to adjust the relative position of the pipe opening of the second pipe section and the ventilation grille 34, so as to improve the cleaning effect on the ventilation grille 34.

[0058] In some embodiments, the opening of the air blowing pipe 37 facing the ventilation grille 34 can be a flat opening, which on the one hand helps to increase the pressure of the ejected gas and improve the cleaning effect; on the other hand, it can increase the spray range. With the air blowing pipe 37 rotating around the first pipe section, the cleaning area of ​​the ventilation grille 34 can be expanded.

[0059] An anti-marine bio-electrode 35 is provided on the inner wall of the venting cavity 39; and / or, a sacrificial anode protection device 36 is provided on the inner wall of the venting cavity 39.

[0060] When marine larvae enter the ventilated cavity 39 through the ventilation grille 34, they easily attach and grow on the inner wall of the cavity 39, affecting the bulkhead. To solve this problem, an anti-marine organism electrode 35 is installed on the inner wall of the ventilated cavity 39. The anti-marine organism electrode 35 can use a platinum-plated titanium electrode or a specially designed electrode to electrolyze seawater. Seawater contains a large amount of salts, primarily sodium chloride, with sodium chloride content being the highest at approximately 2.7%, accounting for 10.9% of the total salinity. Chloride ions are the most abundant component in seawater, with a chlorine concentration of approximately 19%, accounting for 55% of the total ion content. Seawater electrolysis produces sodium hypochlorite, hypochlorous acid, and chlorine gas. This available chlorine is a strong oxidizing agent that can kill marine larvae and spores, achieving the purpose of pollution prevention.

[0061] To prevent corrosion of the venting box 31 and the bottom plate 11 under the influence of seawater, a sacrificial anode protection device 36 is installed on the inner wall of the venting cavity 39. This device utilizes a metal with strong reducing properties as the protective electrode, forming a galvanic cell with the inner wall of the venting cavity 39. The metal with strong reducing properties acts as the negative electrode and undergoes an oxidation reaction, thereby protecting the inner wall of the venting cavity 39 from corrosion. The sacrificial anode protection device 36 is a conventional structure in the field of metal corrosion protection technology and will not be described further in this embodiment.

[0062] To allow impurities such as silt to be discharged from the venting chamber 39, a sand-draining hole 111 communicating with the venting chamber 39 is provided on the bottom plate 11. The silt in the venting chamber 39 can be discharged through the sand-draining hole 111 under the influence of gravity. The sand-draining hole 111 is located at the lowest point of the venting chamber 39 to facilitate the passage of silt under gravity. Optionally, the diameter of the sand-draining hole 111 can be 15–30 mm, for example, 15 mm, 16 mm, 17 mm, 18 mm, 19 mm, 20 mm, 21 mm, 22 mm, 23 mm, 24 mm, 25 mm, 26 mm, 27 mm, 28 mm, 29 mm, or 30 mm.

[0063] The drag-reducing vessel provided in this application includes a hull, a drag-reducing device, and a gas drainage device. The drag-reducing device forms a drag-reducing air layer on the bottom surface of the hull, with a vent located at the stern end of the hull. The gas drainage device includes a venting chamber and an exhaust channel. The venting chamber is located within the hull and communicates with the vent. The exhaust channel is located within the hull, with one end communicating with the venting chamber and the other end passing through the deck. The gas drainage device diverts the overflow gas from the drag-reducing air layer at the stern end of the hull, guiding it through the vent, venting chamber, and exhaust channel to the deck for discharge. This prevents the overflow gas from entering the propeller area and affecting propeller performance, thereby increasing the overall energy-saving and drag-reducing effect of the drag-reducing device.

[0064] The venting chamber and exhaust channel are both located inside the hull, without adding any accessories to the outer wall of the hull, and without increasing the resistance encountered by the hull during navigation, thus avoiding affecting the energy-saving and drag-reducing effect of the drag-reducing air layer.

Claims

1. A drag-reducing vessel, comprising a hull (10) and a drag-reducing device (40), wherein the drag-reducing device (40) is disposed on the hull (10) and configured to form a drag-reducing air layer on the bottom surface of the hull (10), wherein, A vent (19) is provided on the bottom surface of the hull (10) near the stern (15); The drag-reducing vessel also includes a gas venting device (30), which comprises: A venting cavity (39) is disposed inside the hull (10), and the venting cavity (39) is connected to the venting port (19); An exhaust channel (32) is provided inside the hull (10). One end of the exhaust channel (32) is connected to the venting chamber (39), and the other end of the exhaust channel (32) passes through the deck (16) of the hull (10).

2. The air-layer drag-reducing vessel according to claim 1, wherein, The hull (10) includes: Bottom plate(11); Skirt (13), the skirt (13) is set on the outer wall of the bottom plate (11) and connected end to end to form an air cavity (18); A wedge-shaped guide (14) is disposed on the outer wall of the bottom plate (11) and located in the air cavity (18) near the stern (15). The wedge-shaped guide (14) extends along the width direction of the hull (10), and the wedge-shaped surface of the wedge-shaped guide (14) is disposed facing the bow (17).

3. The air-layer drag-reducing vessel according to claim 2, wherein, The wedge-shaped guide (14) is spaced apart from the skirt (13) at at least one end along the width direction of the hull (10) to form an air venting gap (43). The air vent (19) is located outside the air cavity (18) and is located close to the air venting gap (43).

4. The air-layer drag-reducing vessel according to any one of claims 1 to 3, wherein, The hull (10) includes a bottom plate (11) and an inner bottom plate (12) located above the bottom plate (11). The venting cavity (39) is formed between the bottom plate (11) and the inner bottom plate (12), and the vent (19) is disposed on the bottom plate (11).

5. The air-layer drag-reducing vessel according to claim 4, wherein, The gas venting device (30) further includes a venting box (31), which is disposed between the bottom plate (11) and the inner bottom plate (12), and the venting box (31) and the bottom plate (11) form the venting cavity (39).

6. The air-layer drag-reducing vessel according to any one of claims 1 to 3, wherein, The exhaust passage (32) is connected to the top of the venting cavity (39).

7. The air-layer drag-reducing vessel according to any one of claims 1 to 3, wherein, The vent (19) is provided with a breathable grille (34).

8. The air-layer drag-reducing vessel according to claim 7, wherein, The gas venting device (30) further includes an air blowing pipe (37), one end of which is configured to be connected to an air source, and the other end of which is located in the venting cavity (39) and faces the venting grille (34).

9. The air-layer drag-reducing vessel according to any one of claims 1 to 3, wherein, The inner wall of the venting cavity (39) is provided with at least one of the following: a marine bio-electrode (35), or a sacrificial anode protection device (36).

10. The air-layer drag-reducing vessel according to any one of claims 1 to 3, wherein, The bottom surface of the hull (10) is provided with a sand-leaking hole (111) that communicates with the venting cavity (39).

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