Lift amplification device for rotor sail using rotor skins

Abstract

The present invention relates to a device using lift generated by the flow of a fluid, and more specifically to a lift amplification device in which a plurality of rotor skin means are arranged on the outer circumferential surface of a cylindrical rotor sail and rotated so as to increase the difference in flow velocity of a fluid and thus enable amplifying lift. The lift amplification device, according to the present invention, comprises a plurality of rotor skin means and a driving means. The rotor skin means are arranged in a row so as to form a cylindrical shape, and are each provided with: a rotor skin formed as a closed curve belt; and a plurality of rollers supporting the rotor skin from inside the rotor skin so as to enable the rotor skin to be tautly maintained. The driving means rotates the rotor skins so as to increase the flow velocity of a fluid flowing on one side portion of the cylindrical shape and decrease the flow velocity of the fluid flowing on the other side portion of the cylindrical shape, thereby enabling the generation of lift on the cylindrical shape. The lift amplification device, according to the present invention, is configured to have a plurality of rotor skin means arranged along the outer circumferential surface of a structure having a cylindrical shape and have rotor skins rotated, thereby increasing the flow velocity of a fluid flowing on one side portion of the cylindrical shape and decreasing the flow velocity of the fluid flowing on the other side portion of the cylindrical shape, and thus enabling a greater difference in flow velocity of the fluid generated around the cylindrical shape. Accordingly, the effect of enabling the effective increasing of lift generated by a pressure difference of a fluid may be achieved.

Description

Lift amplification device for rotor sails using Lotus Skin

[0001] The present invention relates to a device utilizing lift generated by the flow of a fluid, and more specifically, to a lift amplification device capable of amplifying lift by arranging a plurality of rotor skin means on the outer surface of a cylindrical rotor sail and rotating them to increase the difference in fluid velocity.

[0002] Technologies for generating thrust or power by utilizing forces produced by fluid flow have been studied in various fields. One such technology is a device utilizing the Magnus effect, in which lift is generated by the difference in fluid velocity around a rotating cylinder. A representative device utilizing this principle is the rotor sail.

[0003] A rotor sail is a device that rotates a cylindrical structure. When the cylinder rotates while fluid flow is present, the velocity distribution of the fluid flowing along the outer surface of the cylinder changes. That is, depending on the direction of rotation of the cylinder, the fluid velocity increases on one side of the cylinder and decreases on the other side, and a pressure difference is formed on both sides of the cylinder due to this difference in velocity. Due to this pressure difference, a lift force is generated on the cylinder in a direction perpendicular to the direction of fluid flow.

[0004] Such rotor sails can be utilized as devices to assist in ship propulsion or applied to various devices that use wind and fluid energy. In particular, since rotor sails can generate additional thrust by utilizing wind or fluid flow, they are continuously being researched as a technology to improve energy efficiency.

[0005] This rotor sail technology utilizes the principle of generating lift by changing the fluid flow through the rotation of a cylinder; various structural modifications and application technologies have been proposed, and it is widely known as a form of propulsion and energy utilization device that leverages hydrodynamic properties.

[0006] Registered Patent No. 10-2736569 (Registration Date: November 27, 2024)

[0007] Published Patent No. 10-2025-0093817 (Date of publication: June 25, 2025)

[0008] Published Patent No. 10-2023-0121287 (Date of publication: September 12, 2023)

[0009] Published Patent No. 10-2025-0104167 (Date of publication: July 8, 2025)

[0010] FIG. 7 is a conceptual diagram of a conventional rotor sail. A conventional rotor sail (5) is a device that generates lift by utilizing the pressure difference caused by the flow of fluid by rotating a cylindrical structure. When the rotor sail (5) rotates at a rotational speed R while fluid is flowing, the velocity distribution of the fluid flowing along the outer surface of the rotor sail (5) changes. That is, as shown in FIG. 7, the fluid velocity increases to A1 at the top of the rotor sail (5) and decreases to A2 at the bottom. Due to this difference in velocity, a pressure difference occurs between the top and bottom of the rotor sail (5), and a lift F is generated as a result.

[0011] However, the magnitude of the lift F generated by the conventional rotor sail (5) is proportional to the difference between the flow velocity A1 and the flow velocity A2, and this difference in flow velocity depends significantly on the rotational speed R of the rotor sail (5). Therefore, in order to increase the magnitude of the lift F, the rotational speed R of the rotor sail (5) must be increased. However, since the rotor sail (5) is generally a structure with a large diameter and heavy weight, there are structural and mechanical limitations to significantly increasing the rotational speed R. As a result, it is difficult to form a sufficient difference in flow velocity, and there is a problem in that it is difficult to increase the magnitude of the possible lift F to a desired level.

[0012] In addition, the direction of action of the lift F generated by the conventional rotor sail (5) always has the characteristic of acting perpendicular to the direction of fluid flow, so it is difficult to actively control the direction of action of the lift. As a result, in cases where propulsion force must be utilized in a specific direction, such as in actual ship propulsion, it is difficult to effectively utilize the lift, and consequently, there was a problem that there were limitations in applying the rotor sail to actual ships.

[0013] The present invention was devised to solve the problems of the prior art as described above, and aims to provide a lift amplification device capable of creating a greater difference in fluid velocity by arranging a plurality of rotor skin means on the outer surface of a rotor sail and rotating the rotor skins to increase the fluid velocity flowing toward one side of the cylindrical shape and decrease the fluid velocity flowing toward the other side.

[0014] In addition, another objective of the present invention is to provide a lift amplification device capable of not only increasing the magnitude of the generated lift by configuring the rotational speed and rotational direction of a plurality of lotus skins to be individually controlled, but also actively adjusting the direction of the lift force.

[0015] In addition, another objective of the present invention is to provide a lift amplification device capable of further improving lift generation efficiency by reducing flow loss caused by fluid flowing into the spaces between adjacent lotus skins and facilitating fluid flow through the filler that fills the empty spaces between adjacent lotus skins.

[0016] The lift amplification device according to the present invention comprises a plurality of lotus skin means and a driving means. The lotus skin means comprises a lotus skin made of a closed-curve belt and a plurality of rollers that support the lotus skin to keep it taut inside the lotus skin, and are arranged in a line to form a cylindrical shape. The driving means rotates the lotus skin to increase the flow velocity of the fluid flowing toward one side of the cylindrical shape and decrease the flow velocity of the fluid flowing toward the other side of the cylindrical shape so as to generate lift in the cylindrical shape.

[0017] In addition, it is preferable that the above-described lift amplification device further includes a plurality of fillers arranged to fill the empty spaces between the lotus skins so as to reduce the flow of fluid entering between the adjacent lotus skins.

[0018] In addition, in the above-described lift amplification device, the filler may be a rotatable cylinder.

[0019] In addition, in the above-described lift amplification device, it is preferable that the driving means rotates at least one of the plurality of rollers of the lotus skin means.

[0020] In addition, in the above-described lift amplification device, the driving means may comprise an interlocking unit and a driving unit. The interlocking unit interlocks the rollers of adjacent lotus skin means. The driving unit rotates the roller of any one of the lotus skin means.

[0021] In addition, in the above-described lift amplification device, it is preferable that a plurality of dimples are formed on the lotus skin.

[0022] In addition, the above-described lift amplification device preferably further includes at least one support member mounted along the longitudinal direction of the roller to surround the roller and support it so that the roller can rotate, in order to prevent the roller from bending in the longitudinal direction.

[0023] The lift amplification device according to the present invention is configured to arrange a plurality of lotus skin means along the outer surface of a cylindrical structure and to rotate the lotus skins, thereby increasing the fluid velocity flowing toward one side of the cylindrical shape and decreasing the fluid velocity flowing toward the other side, so that the difference in fluid velocity occurring around the cylindrical shape can be made larger. Accordingly, the lift generated by the pressure difference of the fluid can be effectively increased.

[0024] Furthermore, since the present invention is configured to influence fluid flow using a plurality of lotus skins, the fluid velocity distribution can be effectively changed without rotating the entire large cylindrical structure at high speed as in conventional methods. Accordingly, the efficiency of lift generation can be improved without increasing structural burden.

[0025] Furthermore, since the present invention can be configured to individually control the rotational speed and direction of rotation of the lotus skin, the fluid flow velocity and pressure distribution formed along the outer surface of the cylinder can be actively controlled. Accordingly, not only the magnitude of the generated lift but also the direction of its application can be controlled, allowing the lift to be utilized in a desired direction even in environments where the wind direction or fluid flow direction changes.

[0026] In addition, the present invention can reduce flow loss by suppressing fluid inflow into the empty space between adjacent lotus skins by placing a filler between them, thereby maintaining a smoother fluid flow and further improving lift generation efficiency.

[0027] Accordingly, according to the present invention, a larger lift force can be efficiently generated by utilizing fluid flow, and the controllability of the generated lift force can be improved, making it useful for various fluid-utilizing devices such as ship propulsion aids.

[0028] FIG. 1 is a conceptual diagram of one embodiment of a lift amplification device according to the present invention,

[0029] FIG. 2 is a conceptual diagram of the operation of the embodiment of FIG. 1,

[0030] FIG. 3 is a conceptual diagram of the embodiment of FIG. 1 with a filler applied,

[0031] FIG. 4 is a conceptual diagram of an embodiment of FIG. 1 in which a filler in the form of a rotating cylinder is applied.

[0032] FIG. 5 is a conceptual diagram of the interconnected Lotus Skin in the embodiment of FIG. 1,

[0033] FIG. 6 is a conceptual diagram of the embodiment of FIG. 1 with a support applied.

[0034] Figure 7 is a conceptual diagram of a conventional rotor sail.

[0035] 1 : Rotor Sail

[0036] 10 : Lotus Skin Means 11 : Lotus Skin

[0037] 15 : Roller 20 : Driving means

[0038] 21 : Interlocking part 30 : Filler

[0039] 31: Filler in the form of a rotating cylinder 40: Support

[0040] An embodiment of a lift amplification device according to the present invention will be described with reference to FIGS. 1 to 6. However, the following embodiments are merely examples to specifically explain the technical concept of the present invention, and the scope of the present invention is not limited thereto.

[0041] The lift amplification device according to the present invention basically comprises a plurality of lotus skin means (10) and a driving means (20). Additionally, a plurality of fillers (30) may be further included as needed.

[0042] First, each lotus skin means (10) is equipped with a lotus skin (11) in the form of a closed-loop belt and a plurality of rollers (15) that support the lotus skin (11) to keep it taut inside the lotus skin (11). Here, the lotus skin (11) is a component that rotates while in direct contact with an external fluid and may have a closed-loop structure in the form of an endless track or an endless belt overall. The rollers (15) are positioned inside the lotus skin (11) to maintain the tension of the lotus skin (11) and to support the lotus skin (11) so that it can rotate in a stable circular motion. In this embodiment, an example is illustrated in which two rollers (15) are applied to each lotus skin means (10), but it may be configured with two or more rollers depending on the length, shape, required tension, installation conditions, etc. of the lotus skin (11). That is, the multiple rollers (15) perform the role of maintaining the overall shape of the lotus skin (11) inside the lotus skin (11), preventing sagging or twisting, reducing vibration during rotation, and ensuring that the contact surface with the fluid is smoothly formed.

[0043] A plurality of lotus skin means (10) are arranged in a line to form a cylindrical shape as shown in FIGS. 1 and 2. More specifically, the plurality of lotus skin means (10) are arranged along the outer surface of the lotus sail (1) in a manner that wraps around the lotus sail (1), thereby forming a single cylindrical outer surface overall. Here, “arranged in a line to form a cylindrical shape” means that the plurality of lotus skin means (10) are arranged continuously along the circumferential direction to form a substantially cylindrical surface when viewed from the outside. Thus, each lotus skin means (10) has an independent belt structure, yet is arranged along the outer surface of the lotus sail (1) overall to form an integrated cylindrical structure that interacts with the fluid. With this configuration, instead of rotating the entire large single cylinder, the plurality of lotus skin means (10) arranged along the outer surface can be made to influence the fluid flow.

[0044] The driving means (20) is configured to rotate the rotor skin (11) to increase the flow velocity of the fluid flowing toward one side of the cylindrical shape and decrease the flow velocity of the fluid flowing toward the other side of the cylindrical shape so as to generate lift in the cylindrical shape. That is, the driving means (20) rotates the rotor skin (11) of each rotor skin means (10) in a certain direction to change the relative velocity of the fluid flowing around the cylindrical shape, and accordingly, creates a difference in flow velocity and pressure on both sides of the cylinder to generate lift. Referring to FIG. 2, when the fluid flows past the outside of the rotor sail (1), the flow velocity A1 of the fluid flowing along one side of the cylindrical shape increases due to the rotation of the rotor skin (11), and the flow velocity A2 of the fluid flowing along the other side decreases. Accordingly, the pressure distribution on both sides changes, and as a result, lift F is generated. The present invention is configured to amplify lift by utilizing this very principle.

[0045] The driving method of the driving means (20) can be implemented in various ways. At this time, the driving means can rotate each lotus skin means (10) individually, or all lotus skin means (10) can be linked together to rotate simultaneously.

[0046] When the driving means (20) is implemented in a manner that rotates each lotus skin (11) individually, the driving means (20) rotates at least one of the multiple rollers (15) of each lotus skin means (10). In this case, the driving means (20) directly transmits power to the roller (15) provided in each lotus skin means (10) to rotate the roller (15), and the lotus skin (11) rotates while moving in a circular motion due to the rotation. At this time, the rotational speed can be set differently for each lotus skin means (10), and the rotational direction can also be controlled differently as needed. For example, multiple lotus skins (11) can be driven at different rotational speeds such as X1, X2, X3, etc. In this individual control structure, since the relative motion conditions with the fluid can be set differently at each part located along the outer surface of the cylindrical shape, the flow velocity and pressure of the fluid flowing on the outer surface of each lotus skin (11) can be individually controlled. As a result, it is possible to not only increase the magnitude of the lift force but also control the direction of action of the generated lift force F. That is, even when the direction of wind or fluid flow is not constant or the required direction of propulsion changes depending on the direction of travel of the ship, the lift force F can be controlled to have a large component in the desired direction, such as the direction of travel of the ship, by appropriately adjusting the rotational speed and rotational direction of each rotor skin (11). In this respect, the present invention has superior controllability compared to conventional simple rotating rotor sails.

[0047] When the driving means (20) links all the lotus skin means (10) together to rotate them simultaneously, the driving means (20) may be provided with a linking part (21) that links the rollers (15) of adjacent lotus skin means (10) together as shown in FIG. 5, and a driving part that rotates the roller (15) of any one of the lotus skin means (10). The linking part (21) is provided between the rollers (15) of adjacent lotus skin means (10) so that the rotational force applied to one roller (15) is sequentially transmitted to the adjacent rollers (15). The linking part (21) may be formed, for example, by a connecting belt, chain, gear, or other mechanical transmission means. By using the linking part (21) in this way, even if the driving part rotates only one roller (15) of all the lotus skin means (10), the rollers (15) of the remaining lotus skin means (10) also rotate together through the linking part (21). As a result, all Lotus Skins (11) can rotate in the same direction and at the same or a speed according to the linkage ratio. This configuration has the advantage of reducing the number of driving sources and simplifying the device configuration.

[0048] The present invention may further include a plurality of fillers (30) arranged to fill the empty space between adjacent lotus skins (11). When a plurality of lotus skin means (10) are arranged in a line to form a cylindrical shape, a structural gap or empty space may be formed between each lotus skin (11). If such empty space is left open, external fluid may flow in through it, disrupting the flow that should be formed along the outer surface of the cylinder, and this may result in flow loss and a decrease in lift generation efficiency. To prevent this, the fillers (30) are arranged to fill the empty space between adjacent lotus skins (11). That is, the fillers (30) ensure that the outer surface forms a more continuous and smooth shape when the plurality of lotus skins (11) form a cylindrical shape overall, and suppress the excessive inflow of air into the empty space between the lotus skins (11). Accordingly, the fluid flow along the outer surface of the cylinder is maintained more stably, reducing flow loss and improving lift generation efficiency.

[0049] The filler (30) may be formed as a fixed filling member, but may also be implemented as a filler (31) in the form of a rotatable cylinder as shown in FIG. 4. The filler (31) in the form of a rotatable cylinder is positioned between adjacent lotus skins (11) and is supported so that it can rotate. In this case, if the filler (31) in the form of a rotatable cylinder rotates at the same speed or a similar surface speed as the adjacent lotus skin (11), the fluid flowing along the outer surface of the cylinder can flow more smoothly without causing abrupt frictional resistance or separation at the filler portion. In other words, compared to when the filler (30) is a simple fixed member, when the filler (31) in the form of a rotatable cylinder is applied, the contact surface of the fluid moves actively, so the flow is connected more smoothly and the continuous rotational effect of the entire outer surface of the cylinder can be increased. Therefore, when the filler is a rotatable cylinder, the flow loss between adjacent lotus skins (11) can be further reduced and the lift amplification effect can be increased.

[0050] Additionally, multiple dimples may be formed on the lotus skin (11). The dimples are fine irregularities or depressions formed on the outer surface of the lotus skin (11), and can change boundary layer characteristics, control flow separation points, and reduce energy loss of the flow near the surface when a fluid flows along the surface of the lotus skin (11). This dimple structure can be understood as utilizing hydrodynamic principles similar to the surface of a golf ball, and helps to improve the flow of air along the surface of the lotus skin (11) to form a larger flow velocity difference and a stable pressure distribution. Therefore, forming multiple dimples on the lotus skin (11) can further enhance the lift amplification effect.

[0051] Meanwhile, in the case of the present embodiment, if the roller (15) is formed to be long in the longitudinal direction, the central part of the roller (15) may vibrate in the longitudinal direction when the roller (15) rotates. To prevent this, the lift amplification device of the present embodiment may further include a support member (40). The support member (40) supports the outer surface of the roller (15) with a bearing so that the roller (15) can rotate. In this case, if the length of the roller (15) is long, multiple support members (40) may be mounted along the longitudinal direction of the roller (15). The support member (40) may be fixed to the object on which the lift amplification device of the present embodiment is mounted, and when the support member (40) is provided, the lotus skin (11) is separated into multiple parts along the longitudinal direction of the roller (15) and mounted spaced apart by the width of the support member (40) so that the support member (40) can be mounted.

[0052] The operation of the lift amplification device according to the present invention is described below. When the driving means (20) rotates the lotus skin (11) of the lotus skin means (10) while fluid flow is present, the direction of fluid flow and the direction of surface movement of the lotus skin (11) become the same or similar in a part of the outer surface forming a cylindrical shape, thereby increasing the relative flow velocity, and in the opposite side, the direction of fluid flow and the direction of surface movement of the lotus skin (11) become opposite, thereby decreasing the relative flow velocity. As a result, a fast flow velocity A1 is formed on one side of the cylindrical shape, and a slow flow velocity A2 is formed on the other side. According to the Bernoulli principle, the pressure on the side with the fast flow velocity is relatively lower, and the pressure on the side with the slow flow velocity is relatively higher, so lift F is generated by the pressure difference between the two sides. In the present invention, instead of rotating the entire large cylinder at high speed, a plurality of lotus skins (11) arranged along the outer surface rotate to substantially increase the surface velocity of the outer surface of the cylinder, so the difference between A1 and A2 can be increased more efficiently than in the past. As a result, a greater lift F can be obtained.

[0053] In particular, when the rotational speed or rotational direction of each lotus skin (11) is controlled independently, the degree of acceleration or deceleration of the fluid can be varied at specific parts of the outer surface of the cylinder, so that the composite direction of the lift force can be controlled rather than simply forming a fixed lift force in the up-down or left-right direction. For example, when applied to a ship, even if the direction of the wind changes, the generated lift force F can be made to have a directional component favorable to the ship's forward direction by adjusting the rotational conditions of each lotus skin (11). Therefore, the present invention can be particularly useful as a ship propulsion aid.

[0054] In addition, the lift amplification device of the present invention can be mounted on the outer surface of a rotatable rotor sail (1) and used, or it can be installed on the outer surface of a fixed cylinder and implemented to perform the role of a rotor sail itself. When mounted on the outer surface of a rotatable rotor sail (1), the rotational force of the rotor skin means (10) is added to the rotational force of the rotor sail (1), so a much higher lift can be achieved compared to a conventional rotor sail (1).

[0055] In addition, when installed on the outer surface of a fixed cylinder, even if the central cylindrical structure itself does not rotate, if only the plurality of rotor skin means (10) arranged along the outer surface rotate, a change in the relative surface velocity with respect to the fluid occurs, thereby enabling the realization of a lift generation effect substantially similar to a rotor sail. That is, the lift amplification device of the present invention has a structure in which a plurality of rotor skin means (10), each comprising a rotor skin (11) made of a closed-curve belt and a plurality of rollers (15), are arranged in a cylindrical shape, and the rotor skin (11) is rotated by a driving means (20) to increase the flow velocity of the fluid flowing toward one side of the cylindrical shape and decrease the flow velocity of the fluid flowing toward the other side, thereby generating and amplifying lift. Furthermore, a plurality of fillers (30) may be arranged between adjacent rotor skins (11), and the fillers (30) may be fillers (31) made of rotatable cylinders. Furthermore, the driving means (20) may be implemented by directly rotating at least one of the rollers (15), or by including a linkage unit (21) that links adjacent rollers (15) together and a driving unit that rotates one of the rollers (15). Additionally, a plurality of dimples may be formed on the surface of the lotus skin (11).

Claims

1. A lotus skin made of a closed-curve belt, and a plurality of rollers supporting the lotus skin to keep the lotus skin taut inside the lotus skin, and a plurality of lotus skin means arranged in a row to form a cylindrical shape, and A lift amplification device characterized by including a driving means for rotating the lotus skin to increase the flow velocity of the fluid flowing to one side of the cylindrical shape and decrease the flow velocity of the fluid flowing to the other side of the cylindrical shape so as to generate lift in the cylindrical shape.

2. In Paragraph 1, A lift amplification device characterized by further including a plurality of fillers arranged to fill the empty space between the adjacent lotus skins so as to reduce the flow of fluid entering between the lotus skins.

3. In Paragraph 2, A lift amplification device characterized in that the above-mentioned filler is a rotatable cylinder.

4. In paragraph 2, the driving means is A lift amplification device characterized by rotating at least one of the plurality of rollers of the above-mentioned lotus skin means.

5. In paragraph 2, the driving means is A linkage unit that links the rollers of the adjacent Lotus Skin means together, and A lift amplification device characterized by having a driving unit that rotates the roller of any one of the above-mentioned lotus skin means.

6. In any one of paragraphs 1 through 5, A lift amplification device characterized by having a plurality of dimples formed on the above-mentioned lotus skin.

7. In any one of paragraphs 1 through 5, A lift amplification device characterized by further including at least one support member mounted along the longitudinal direction of the roller to surround the roller and support the roller so that the roller can rotate, in order to prevent the roller from bending in the longitudinal direction.

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