Marine rotor sail with array airfoils

Abstract

The invention discloses a marine rotor sail with array airfoils, and belongs to the technical field of sail boosting ships. Aiming at the problem of low aerodynamic efficiency caused by surface airflow separation and end vortex of a traditional rotor sail, a plurality of array airfoils are uniformly arranged on the periphery of a rotor main body, an end plate with a flow guide groove is arranged at the top, and a Magnus effect is enhanced and airflow separation is delayed by utilizing a circular rector superposition effect generated by the airfoils; and meanwhile, an end flow field is reconstructed through the flow guide grooves, vortex energy loss is restrained, and the aerodynamic performance and the lift force characteristic of the rotor are remarkably improved. According to the structure, the adaptability of the sail under various wind direction conditions is effectively improved, a better boosting effect can be provided under the same energy consumption, and the sail is suitable for an efficient propulsion system of a modern green ship and has a good engineering application prospect.

Description

Technical Field

[0001] This invention relates to the field of sail-propelled ship technology, and in particular to a marine rotor sail with an array of airfoils. Background Technology

[0002] In recent years, with the increasing urgency of energy conservation and emission reduction in the global shipping industry, and the gradual increase in the International Maritime Organization's (IMO) requirements for the Energy Efficiency Design Index (EEDI) of ships, energy conservation and emission reduction have become an urgent issue for the shipping industry. As a green energy propulsion technology, sail-assisted propulsion has regained widespread attention in recent years. There are many types of sails, including rotor sails, airfoil sails, extracted turbine sails, kite sails, and so on. Rotary sails have become a research hotspot due to their simple structure and zero carbon emissions. However, traditional rotor sails suffer from low efficiency due to limitations in aerodynamic efficiency caused by surface airflow separation and end vortex kinetic energy loss. To address these issues with traditional rotor sails, the solution lies in optimizing the rotor surface structure, leading to the innovative development of marine rotor sails with arrayed airfoils. Summary of the Invention

[0003] In view of the shortcomings of the low aerodynamic efficiency of existing traditional rotor sails, the present invention aims to provide a marine rotor sail with an array airfoil that effectively improves the defects of low aerodynamic efficiency caused by airflow separation on the surface of traditional rotor sails and the loss of kinetic energy by end vortices.

[0004] This invention proposes a marine rotor sail with an arrayed airfoil, the core of which includes the following technical solutions:

[0005] A marine rotor sail with an array airfoil includes a rotor body, an array airfoil, and a top endplate.

[0006] One end of the rotor body is connected to the lower surface of the top end plate, and the array airfoil surrounds the rotor body, with one end also connected to the lower surface of the top end plate.

[0007] The array airfoil generates synergistic flow through circulation superposition, thereby enhancing the Magnus effect and suppressing airflow separation.

[0008] Furthermore, the array airfoil is composed of multiple airfoils.

[0009] Furthermore, each airfoil is an asymmetric cross-section airfoil, and the maximum thickness of each airfoil is located in the middle region of the airfoil chord to improve aerodynamic lift and drag characteristics.

[0010] Furthermore, the span of each airfoil is set according to the height of the rotor body to ensure the stability of the overall structure while achieving aerodynamic coupling.

[0011] Furthermore, each airfoil has a radial clearance with the circumferential outer surface of the rotor body to improve the overall flow field distribution and avoid interference from the array of airfoils during the operation of the rotor body.

[0012] Furthermore, the chord length of each airfoil is set according to the diameter of the upper and lower surfaces of the rotor body to ensure structural strength.

[0013] Furthermore, the lower surface of the top end plate is provided with a flow guiding groove, and the bottom surface of the flow guiding groove is provided with the same number of mounting slots as the airfoils. Each airfoil is installed in the flow guiding groove on the lower surface of the top end plate through the mounting slot, so as to realize comprehensive control of the end flow field of the rotor body.

[0014] Furthermore, the center orientation of the flow-guiding groove corresponds to the line connecting the leading edge to the trailing edge of the array airfoil, which is used to ensure that the mainstream airflow from above can be guided and flow orderly along each airfoil surface.

[0015] Furthermore, the cross-sectional shape and depth of the flow-guiding groove are set according to the actual airflow conditions to reconstruct the turbulent airflow at the end.

[0016] Furthermore, when natural wind blows over the rotating rotor body, the array airfoils themselves generate aerodynamic lift. At the same time, through the superposition of circulation between multiple airfoils, the stability of the boundary layer gas flow on the surface of the rotor body is ensured, and airflow separation is suppressed.

[0017] The top end plate and the flow-guiding grooves on its lower surface constitute the end flow field control structure. The top end plate blocks the upper and lower airflows, and the flow-guiding grooves guide the airflow reaching the end, so that the airflow conforms to the curve of each airfoil, reconstructs the structure of the end flow field, and suppresses the formation of end vortices in each airfoil.

[0018] The beneficial effects of this invention are as follows:

[0019] Compared with existing technologies, this invention features a simple structure, convenient processing, easy installation, and easy integration with existing ship systems. This design breaks through the limitations of traditional rotor sails that focus solely on single structural optimization, achieving synergistic optimization of aerodynamic efficiency and energy loss suppression, providing an innovative solution for high-efficiency ship propulsion systems. Specifically, by employing circumferentially uniformly distributed asymmetric array airfoils, the equivalent aerodynamic area of ​​the rotor is increased. Based on the Magnus effect, an airfoil lift mechanism is introduced to synergistically enhance thrust output. Through rational design of the radial spacing between the airfoil and the rotor, boundary layer modulation using gap flow is achieved while avoiding structural interference, improving airflow adhesion. The integrated design of the top end plate and guide groove effectively suppresses end-flow losses and improves airflow utilization efficiency, with significant performance improvements, especially under large-angle oncoming wind conditions. Attached Figure Description

[0020] Figure 1 This is a three-dimensional reference diagram of the present invention.

[0021] Figure 2 This is a front view of the basic structure of the present invention.

[0022] Figure 3 This is a cross-sectional view of the present invention.

[0023] Figure 4 This is a schematic diagram of the external airflow of the present invention. Detailed Implementation

[0024] The present invention will now be further described with reference to the accompanying drawings.

[0025] A marine rotor sail with an array airfoil includes a rotor body 1, an array airfoil 2, and a top end plate 3.

[0026] refer to Figure 1 The rotor body 1 is connected at one end to the lower surface of the top end plate 3, and the array airfoil 2 surrounds the rotor body 1, with one end also connected to the lower surface of the top end plate 3.

[0027] The array airfoil 2 generates synergistic flow through circulation superposition, thereby enhancing the Magnus effect and suppressing airflow separation.

[0028] refer to Figure 3 Furthermore, the array airfoil 2 is composed of multiple airfoils.

[0029] Furthermore, each airfoil is an asymmetric cross-section airfoil, and the maximum thickness of each airfoil is located in the middle region of the airfoil chord to improve aerodynamic lift and drag characteristics.

[0030] Furthermore, the span of each airfoil is set according to the height of the rotor body 1, in order to ensure the stability of the overall structure while achieving aerodynamic coupling.

[0031] Furthermore, each airfoil is provided with a radial gap with the circumferential outer surface of the rotor body 1 to improve the overall flow field distribution and avoid interference from the array airfoil 2 during the operation of the rotor body 1.

[0032] Furthermore, the chord length of each airfoil is set according to the diameter of the upper and lower surfaces of the rotor body 1 to ensure structural strength.

[0033] refer to Figure 1 Furthermore, the lower surface of the top end plate 3 is provided with a flow guiding groove 4, and the bottom surface of the flow guiding groove 4 is provided with an installation groove 5 of the same number as the airfoil. Each airfoil is installed in the flow guiding groove 4 on the lower surface of the top end plate 3 through the installation groove 5, so as to realize the comprehensive control of the end flow field of the rotor body 1.

[0034] Furthermore, the center direction of the flow-guiding groove 4 corresponds to the line connecting the leading edge to the trailing edge of the array airfoil 2, which is used to ensure that the mainstream airflow from above can be guided and flow orderly along the surface of each airfoil.

[0035] Furthermore, the cross-sectional shape and depth of the flow guide groove 4 are set according to the actual airflow conditions to reconstruct the turbulent airflow at the end.

[0036] Furthermore, when natural wind blows over the rotating rotor body 1, the array airfoil 2 generates aerodynamic lift. At the same time, through the superposition of circulation between multiple airfoils, the stability of the boundary layer gas flow on the surface of the rotor body 1 is ensured, and airflow separation is suppressed.

[0037] The top end plate 3 and the flow-guiding groove 4 provided on its lower surface constitute the end flow field control structure; the top end plate 3 blocks the upper and lower airflows, and the flow-guiding groove 4 guides the airflow reaching the end, so that the airflow conforms to the curve of each airfoil, reconstructs the structure of the end flow field, and suppresses the formation of end vortices of each airfoil.

[0038] Example

[0039] like Figures 1 to 4 As shown, the present invention provides a high-performance marine rotor sail aerodynamic performance optimization structure with array airfoil, which mainly includes rotor body 1, array airfoil 2, top end plate 3 and flow guide groove 4 provided on the lower surface of end plate.

[0040] The rotor body 1 is a cylindrical structure with a vertically arranged axis, allowing it to rotate around its central axis. The outer surface of the rotor body is kept smooth to reduce wind resistance and friction loss. The rotor body is typically made of lightweight, high-strength composite materials and can integrate a drive device and control system internally to achieve speed adjustment and control.

[0041] The array of airfoils 2 comprises multiple airfoils, the number of which can be configured according to the rotor diameter and aerodynamic requirements. Each airfoil is fixed to the outer periphery of the rotor body 1 via a root mounting slot 5, maintaining a uniform circumferential spacing. The chord length of the airfoil is parallel to the rotor axis, and its cross-section preferably adopts an asymmetric airfoil, with the maximum thickness located in the middle region of the chord length to optimize lift and drag characteristics. A certain radial clearance is maintained between the array of airfoils and the outer surface of the rotor body. This clearance is aerodynamically optimized to avoid interference between the rotor and the airfoils during rotation and to help improve the flow field coupling effect between them.

[0042] The top end plate 3 is a disc-shaped structure that covers the top of the rotor body 1 and the array airfoil 2. The outer diameter of the end plate is larger than the maximum circumscribed circle diameter of the array airfoil profile to effectively suppress the generation of end vortices. The end plate is fixedly connected to the upper end of each array airfoil, thereby enhancing the overall structural rigidity.

[0043] The flow-guiding groove 4 is located on the lower surface of the top end plate 3 and is a continuous annular channel structure along the circumference. The center direction of the groove corresponds to the line connecting the leading edge and trailing edge of the airfoil, ensuring that the mainstream airflow from above can be effectively guided and flow orderly along the airfoil surface. The cross-sectional shape and depth of the flow-guiding groove can be optimized according to the actual airflow conditions. Its core function is to reconstruct the turbulent airflow at the end, reduce vortex intensity, and reduce energy loss.

[0044] The usage and working principle of this invention are as follows:

[0045] This rotor sail structure is installed on the ship's deck and can adjust the rotation direction and speed of the rotor body according to the wind direction sensor signal. When natural wind blows, the rotor rotates under power, and its surface generates lift perpendicular to the direction of the incoming flow based on the Magnus effect, providing propulsion assistance to the ship.

[0046] In this invention, the circumferentially arranged array airfoils 2 play a key role: they not only generate aerodynamic lift themselves, but more importantly, through the superposition of circulation between multiple airfoils, they significantly enhance and stabilize the boundary layer flow on the rotor surface, effectively delaying or even suppressing airflow separation, thereby greatly improving the overall aerodynamic efficiency of the rotor.

[0047] Meanwhile, the top endplate 3 and the flow-guiding groove 4 on its lower surface together constitute the end flow field control system. The top endplate 3 physically blocks the mixing of the upper and lower airflows, while the flow-guiding groove 4 actively guides the airflow arriving at the end, making it more closely conform to the airfoil curvature and develop backward, reconstructing the end flow field structure, greatly suppressing the generation and development of wingtip vortices, reducing induced drag, and further improving the lift performance and energy utilization of the sail.

[0048] This structure achieves a systematic improvement in the aerodynamic performance of the rotor sail through the synergistic effect of the rotor body 1, the array airfoil 2, and the guide groove 4. Its rational structure facilitates processing and installation, and it can be widely used in various commercial vessels such as cargo ships, tankers, and bulk carriers. As an important energy-saving propulsion device, it significantly reduces main engine fuel consumption and greenhouse gas emissions.

[0049] The above description is merely a preferred embodiment of the present invention and is not intended to limit the invention. Various modifications and variations can be made to the present invention by those skilled in the art. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present invention should be included within the scope of protection of the present invention.

Claims

1. A marine rotor sail with an array of airfoils, characterized in that: It includes a rotor body (1), an array airfoil (2), and a top end plate (3); One end of the rotor body (1) is connected to the lower surface of the top end plate (3), and the array airfoil (2) surrounds the rotor body (1) and one end is connected to the lower surface of the top end plate (3). The array airfoil (2) generates synergistic flow through circulation superposition, thereby enhancing the Magnus effect and suppressing airflow separation.

2. A marine rotor sail with an arrayed airfoil as described in claim 1, characterized in that: The array airfoil (2) is composed of multiple airfoils.

3. A marine rotor sail with an arrayed airfoil as described in claim 2, characterized in that: Each airfoil is an asymmetric cross-section airfoil, with the maximum thickness of each airfoil located in the middle region of the airfoil chord to improve aerodynamic lift and drag characteristics.

4. A marine rotor sail with an arrayed airfoil as described in claim 3, characterized in that: The span of each airfoil is set according to the height of the rotor body (1) to ensure the stability of the overall structure while achieving aerodynamic coupling.

5. A marine rotor sail with an arrayed airfoil as described in claim 4, characterized in that: Each airfoil has a radial gap with the circumferential outer surface of the rotor body (1) to improve the overall flow field distribution and avoid interference from the array airfoil (2) during the operation of the rotor body (1).

6. A marine rotor sail with an arrayed airfoil as described in claim 5, characterized in that: The chord length of each airfoil is set according to the diameter of the upper and lower surfaces of the rotor body (1) to ensure structural strength.

7. A marine rotor sail with an arrayed airfoil as described in claim 6, characterized in that: The lower surface of the top end plate (3) is provided with a flow guide groove (4), and the bottom surface of the flow guide groove (4) is provided with the same number of mounting slots (5) as the airfoils. Each airfoil is installed in the flow guide groove (4) on the lower surface of the top end plate (3) through the mounting slot (5) to achieve comprehensive control of the end flow field of the rotor body (1).

8. A marine rotor sail with an arrayed airfoil according to claim 7, characterized in that: The center direction of the flow guide groove (4) corresponds to the line connecting the leading edge to the trailing edge of the array airfoil (2), which is used to ensure that the mainstream airflow from above can be guided and flow orderly along the surface of each airfoil.

9. A marine rotor sail with an arrayed airfoil as described in claim 8, characterized in that: The cross-sectional shape and depth of the flow guide groove (4) are set according to the actual airflow conditions, and are used to reconstruct the turbulent airflow at the end.

10. A marine rotor sail with an arrayed airfoil according to claim 9, characterized in that: When natural wind blows over the rotating rotor body (1), the array airfoil (2) generates aerodynamic lift. At the same time, through the superposition of circulation between multiple airfoils, the stability of the boundary layer gas flow on the surface of the rotor body (1) is ensured, and airflow separation is suppressed. The top end plate (3) and the flow guide groove (4) provided on its lower surface constitute the end flow field control structure; the top end plate (3) blocks the upper airflow and the lower airflow, and the flow guide groove (4) guides the airflow that arrives at the end, so that the airflow fits the curve of each airfoil, reconstructs the structure of the end flow field, and suppresses the formation of end vortices of each airfoil.

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