Blades, propellers, power propulsion devices and vessels

Abstract

The application provides a paddle, a propeller, a power propulsion device and a ship, and relates to the technical field of propeller noise control, wherein the paddle comprises a blade root, a blade body and a blade tip which are sequentially connected; the blade body has a first pressure surface and a first suction surface which are oppositely arranged, in the process of rotation of the paddle, fluid can flow from the position of the first pressure surface to the position of the first suction surface; at least a part of the blade tip is curved towards the first pressure surface. In the technical scheme of the application, at least a part of the blade tip is curved towards the first pressure surface of the blade body, and this design is beneficial to the structural optimization of the blade tip, can greatly inhibit vortex-induced resonance and reduce noise pollution.

Description

Technical Field

[0001] This invention relates to the field of propulsion noise control technology, and more specifically, to a blade, a propeller, a power propulsion device, and a ship. Background Technology

[0002] According to the International Maritime Organization (IMO) regulations on the control of marine noise and guidelines for reducing underwater noise from commercial vessels, ships should not cause excessive noise pollution to their surroundings while navigating. As the most mainstream and widely used propulsion device in the shipbuilding industry, the noise problem of propellers has always been a key focus for researchers.

[0003] Propellers typically operate in non-uniform turbulent flow, where vortex shedding occurs at the blade tips, accompanied by cavitation. Experimental studies have found that vortex shedding at the blade tips leads to increased propeller vibration and may cause vortex-induced resonance. This phenomenon significantly increases propeller vibration noise and greatly amplifies noise pollution to the surrounding environment during ship navigation.

[0004] Therefore, optimizing the blade tip structure to reduce vibration and noise caused by vortex-induced resonance is an urgent problem to be solved. Summary of the Invention

[0005] In order to solve or improve at least one of the above-mentioned technical problems, one object of the present invention is to provide a blade.

[0006] Another object of the present invention is to provide a propeller.

[0007] Another object of the present invention is to provide a power propulsion device.

[0008] Another object of the present invention is to provide a ship.

[0009] To achieve the above objectives, a first aspect of the present invention provides a blade comprising a blade root, a blade body, and a blade tip connected in sequence. The blade body has a first pressure surface and a first suction surface disposed opposite to each other. During blade rotation, fluid can flow from the position of the first pressure surface to the position of the first suction surface. At least a portion of the blade tip bends toward the first pressure surface.

[0010] The present invention aims to provide a blade in which at least a portion of the blade tip is bent toward the first pressure surface of the blade body. This design facilitates structural optimization of the blade tip, can suppress vortex-induced resonance to a large extent, and reduce noise pollution.

[0011] In addition, the technical solution provided by the present invention may also have the following additional technical features:

[0012] In some technical solutions, the leaf tip optionally includes a leaf tip body and an open annular structure. The leaf tip body is connected to the leaf blade. The open annular structure is located at the end of the leaf tip body away from the leaf blade, and at least a portion of the open annular structure is bent towards the first pressure surface.

[0013] In this technical solution, without changing the propeller blade profile, an open annular structure is provided, and at least a portion of the open annular structure is bent toward the first pressure surface. This design helps to suppress eddies and reduce propeller vibration noise, thereby improving the propeller's acoustic performance and reducing underwater noise pollution from ships.

[0014] In some technical solutions, optionally, the open annular structure has a second pressure surface and a second suction surface disposed opposite to each other. The second pressure surface is connected to the first pressure surface and located on the same side of the blade; the second suction surface is connected to the first suction surface and located on the same side of the blade. At least a portion of the second suction surface is disposed on the side of the first pressure surface opposite to the first suction surface.

[0015] In this technical solution, the second suction surface and the second pressure surface of the open annular structure are twisted so that at least a portion of them are located on the side of the first pressure surface away from the first suction surface. This design helps to weaken the tip vortex intensity, thereby suppressing propeller vortex-induced vibration, effectively improving the propeller's acoustic performance and reducing underwater noise pollution from ships.

[0016] In some technical solutions, the open annular structure and the main body of the blade tip can optionally be an integrated structure.

[0017] In this technical solution, this design method does not require changing the blade shape of the propeller body. It only requires bending or twisting the blade tip towards the first pressure surface to form an open annular structure.

[0018] In some technical solutions, the open annular structure and the main body of the leaf tip can be separate structures, and the open annular structure is connected to the main body of the leaf tip.

[0019] In this technical solution, this design method makes it easy for staff to disassemble and assemble the open ring structure, which is beneficial for maintenance or replacement.

[0020] In other words, a portion of the leaf tip is cut off, while the main body of the leaf tip is retained; an open ring structure with the same linear shape as the cut surface is spliced ​​to the cut surface of the leaf tip.

[0021] In some technical solutions, optionally, the inner contour of the cross-section of the open annular structure is an arc, and the central angle corresponding to the arc is 175 degrees to 185 degrees.

[0022] In this technical solution, this design ensures that at least a portion of the second suction surface is located on the side of the first pressure surface away from the first suction surface, which helps to weaken the tip vortex intensity and achieve the purpose of suppressing propeller vortex-induced vibration.

[0023] In some technical solutions, optionally, the radial dimension of the blade is a first dimension, and the radial dimension of the open annular structure along the blade is a second dimension, wherein the second dimension is 4% to 6% of the first dimension.

[0024] In this technical solution, this design ensures that an open annular structure is provided without changing the propeller blade profile, and at least a portion of the open annular structure bends toward the first pressure surface, which helps to suppress eddies and reduce propeller vibration noise.

[0025] A second aspect of the present invention provides a propeller, comprising a central shaft and blades as described in any of the above-described technical solutions. The blade roots are connected to the central shaft.

[0026] Since the propeller includes any of the blades mentioned in the first aspect above, it has the beneficial effects of any of the above technical solutions, which will not be elaborated here.

[0027] A third aspect of the present invention provides a power propulsion device, including a drive component and a propeller as described above. The propeller is connected to the drive component.

[0028] Since the power propulsion device includes the propeller mentioned in the second aspect above, it has the beneficial effects of the above-mentioned technical solution, which will not be elaborated here.

[0029] A fourth aspect of the present invention provides a ship, including a hull and a propulsion device as described above. The propulsion device is connected to a drive component.

[0030] Since the ship includes the power propulsion device mentioned in the third aspect above, it has the beneficial effects of the above technical solution, which will not be elaborated here.

[0031] Additional aspects and advantages of the technical solutions of the present invention will become apparent in the following description or may be learned by practice of the invention. Attached Figure Description

[0032] Figure 1 A schematic diagram of the blade structure according to an embodiment of the present invention is shown;

[0033] Figure 2 A schematic diagram of a propeller according to an embodiment of the present invention is shown;

[0034] Figure 3 A schematic diagram of a propeller according to another embodiment of the present invention is shown;

[0035] Figure 4 A schematic diagram of a propeller according to another embodiment of the present invention is shown;

[0036] Figure 5 A structural block diagram of a power propulsion device according to an embodiment of the present invention is shown;

[0037] Figure 6 A structural block diagram of a ship according to an embodiment of the present invention is shown;

[0038] Figure 7 A schematic diagram of propeller tip vortices in related technologies is shown;

[0039] Figure 8 A schematic diagram of the flow field at the tip of a blade according to an embodiment of the present invention is shown.

[0040] in, Figures 1 to 6 The correspondence between the reference numerals and component names in the attached drawings is as follows:

[0041] 100: Blade; 110: Blade root; 120: Blade body; 121: First pressure surface; 122: First suction surface; 130: Blade tip; 131: Blade tip body; 132: Open annular structure; 133: Second pressure surface; 134: Second suction surface; 200: Propeller; 210: Central shaft; 300: Power propulsion device; 310: Drive component; 400: Ship; 410: Hull. Detailed Implementation

[0042] To better understand the above-described objectives, features, and advantages of the embodiments of the present invention, the embodiments of the present invention will be further described in detail below with reference to the accompanying drawings and specific embodiments. It should be noted that, unless otherwise specified, the embodiments and features described in these embodiments can be combined with each other.

[0043] Many specific details are set forth in the following description in order to provide a full understanding of this application. However, embodiments of the invention may also be implemented in other ways different from those described herein. Therefore, the scope of protection of this application is not limited to the specific embodiments disclosed below.

[0044] The following reference Figures 1 to 8 The invention describes a blade 100, a propeller 200, a power propulsion device 300, and a ship 400 provided according to some embodiments of the invention.

[0045] In one embodiment of the invention, such as Figure 1As shown, the propeller blade 100 includes a blade root 110, a blade body 120, and a blade tip 130 connected in sequence. The portion of the propeller blade 100 closest to the central shaft 210 is called the blade root 110. The blade root 110 is used to connect to the central shaft 210 of the propeller 200. Optionally, the blade root 110 and the central shaft 210 are detachably connected, facilitating disassembly and assembly of the propeller blade 100 by personnel, and aiding in maintenance or replacement.

[0046] The blade 120 is the main body of the blade 100, extending from the root 110 to the tip 130. The blade 120 has a certain degree of twist and curvature. The twisted shape allows the blade 100 to have a reasonable angle of attack at different radii, ensuring that all parts of the blade 100 can effectively do work on the fluid and generate thrust during rotation. The surface of the blade 120 is generally smooth to reduce fluid resistance.

[0047] The blade 120 has a first pressure surface 121 and a first suction surface 122 that are arranged opposite to each other. During the rotation of the blade 100, fluid can flow from the position of the first pressure surface 121 to the position of the first suction surface 122.

[0048] During the rotation of the blade 100, the pressure of the fluid on the first suction surface 122 side of the blade 120 is lower than the pressure of the fluid on the first pressure surface 121 side of the blade 120. Therefore, the fluid can flow from the position of the first pressure surface 121 to the position of the first suction surface 122.

[0049] It should be noted that the blade 100 has a pressure surface and a suction surface arranged opposite to each other. The pressure surface of the blade 100 can be understood as the thrust surface of the blade 100, used to propel the fluid. During the rotation of the blade 100, the pressure of the fluid on the suction surface side of the blade 100 is lower than the pressure of the fluid on the pressure surface side of the blade 100. The first suction surface 122 is a part of the suction surface of the blade 100; the first pressure surface 121 is a part of the pressure surface of the blade 100.

[0050] The tip 130 is the outermost part of the blade 100. For example... Figure 2 As shown, at least a portion of the blade tip 130 bends toward the first pressure surface 121.

[0051] During the operation of propeller 200, the blade tip 130 has the fastest speed, and the hydrodynamic phenomena around it are relatively complex. For example, in non-uniform turbulence, vortex shedding is prone to occur locally at the blade tip 130, which may be accompanied by cavitation. These phenomena will lead to increased vibration and noise of propeller 200.

[0052] The present invention aims to provide a blade 100 in which at least a portion of the blade tip 130 is bent toward the first pressure surface 121 of the blade body 120. This design is beneficial for structural optimization of the blade tip 130, which can suppress vortex-induced resonance to a large extent and reduce noise pollution.

[0053] In one specific embodiment, the blade root 110 and the central shaft 210 are detachably connected by a key connection or an interference fit. Furthermore, when the blade root 110 and the central shaft 210 are connected, the blade root 110 and the central shaft 210 are relatively fixed in the circumferential direction so that the central shaft 210 transmits torque to the blade 100.

[0054] Turbulence is a flow state of a fluid (liquid or gas). In turbulence, fluid particles move irregularly, and the values ​​of various physical quantities (such as velocity and pressure) in the flow field vary randomly with time and spatial location. Non-uniform turbulence refers to flow where the distribution of these physical quantities is not only random but also spatially non-uniform throughout the flow field. For example, in a river, due to variations in riverbed shape, water depth, and the presence of obstacles (such as reefs and bridge piers), the velocity and direction of the water flow can differ significantly at different locations; this type of flow is non-uniform turbulence.

[0055] The causes of non-uniform turbulence can be broadly categorized into three types: changes in boundary conditions, differences in fluid properties, and external disturbances.

[0056] Regarding "changes in boundary conditions": When a fluid flows through different boundaries, the frictional force and resistance exerted by the boundary on the fluid are different, causing physical quantities such as fluid velocity to change near the boundary.

[0057] Regarding "differences in fluid properties": If a fluid is a mixture of different components, or if the fluid's physical properties, such as temperature and density, vary spatially, it can also lead to non-uniform turbulence. For example, in the ocean, the flow between layers of seawater with different salinity and temperature will generate complex non-uniform turbulence due to density differences.

[0058] Regarding "external disturbances": External factors such as vibration and impacts from other fluids can also cause non-uniform turbulence.

[0059] When the propeller 200 operates in non-uniform turbulence, vortex shedding occurs locally at the blade tip 130. This is because non-uniform turbulence causes uneven distribution of fluid pressure and velocity around the blade tip 130, leading to the formation and shedding of vortices. These shedding vortices cause vibration of the propeller 200 and may be accompanied by cavitation. When the pressure in the vortex drops below the liquid's saturated vapor pressure, the liquid vaporizes to form bubbles, which is the phenomenon of cavitation. These bubbles rapidly collapse in the high-pressure region, generating impact pressure, further increasing the vibration and noise of the propeller 200.

[0060] Applying the blade 100 provided by the present invention to the propeller 200 and optimizing the structure of the blade tip 130 helps to suppress vortex-induced resonance, thereby reducing the vibration and noise of the propeller 200 and improving the acoustic performance of the propeller 200.

[0061] In some embodiments, optionally, such as Figure 2 As shown, the leaf tip 130 includes a leaf tip body 131 and an open annular structure 132. The leaf tip body 131 is connected to the leaf body 120. The open annular structure 132 is located at the end of the leaf tip body 131 away from the leaf body 120, and at least a portion of the open annular structure 132 is bent toward the first pressure surface 121.

[0062] Without changing the main blade shape of the propeller 200, an open annular structure 132 is provided, and at least a portion of the open annular structure 132 is bent toward the first pressure surface 121. This design helps to suppress eddies and reduce the vibration noise of the propeller 200, thereby improving the acoustic performance of the propeller 200 and reducing underwater noise pollution of the ship 400.

[0063] In some embodiments, the open annular structure 132 and the blade tip body 131 are optionally integrated. This design does not require changing the blade shape of the propeller 200 body; it only requires bending or twisting the blade tip 130 of the blade 100 toward the first pressure surface 121 to form the open annular structure 132.

[0064] It is important to emphasize that the open annular structure 132 and the blade tip body 131 are an integral structure. Compared with a split structure, this has better mechanical properties and higher connection strength, which helps to reduce the number of parts and improve assembly efficiency. In addition, this design does not affect the overall profile of the blade 100, ensuring the structural performance of the blade 100.

[0065] In one specific embodiment, the tip 130 of the blade 100 is twisted 180 degrees toward the first pressure surface 121 to form an open annular structure 132.

[0066] In some embodiments, the open annular structure 132 and the leaf tip body 131 are optionally separate structures, and the open annular structure 132 is connected to the leaf tip body 131. This design facilitates the disassembly and assembly of the open annular structure 132 by workers, which is beneficial for maintenance or replacement.

[0067] In other words, a portion of the leaf tip 130 is cut off, while the main body of the leaf tip 131 is retained; and an open annular structure 132 with the same linear shape as the cut surface is spliced ​​to the cut surface of the leaf tip.

[0068] The specific shape and thickness of the open ring structure 132 are adjusted appropriately according to the structural strength requirements.

[0069] In one specific embodiment, a portion of the leaf tip 130 is truncated, and then an annular semi-tubular structure with the same linear shape as the truncated surface is spliced ​​to the truncated surface of the leaf tip. The annular semi-tubular structure is the open annular structure 132, with a bending angle of 180 degrees.

[0070] In some embodiments, the blade tip body 131 and the blade body 120 are optionally integrated, which offers better mechanical properties and higher connection strength compared to a separate structure, thus reducing the number of parts and improving assembly efficiency. Furthermore, this design does not affect the overall profile of the blade 100, ensuring its structural performance.

[0071] In some embodiments, the open annular structure 132 may optionally have a second pressure surface 133 and a second suction surface 134 disposed opposite to each other.

[0072] The second pressure surface 133 is connected to the first pressure surface 121 and is located on the same side of the blade 100; the second suction surface 134 is connected to the first suction surface 122 and is located on the same side of the blade 100.

[0073] It should be noted that the second pressure surface 133 is part of the pressure surface of the blade 100; the second suction surface 134 is part of the suction surface of the blade 100.

[0074] At least a portion of the second suction surface 134 is disposed on the side of the first pressure surface 121 opposite to the first suction surface 122.

[0075] By twisting the second suction surface 134 and the second pressure surface 133 of the open annular structure 132, at least a portion of them are located on the side of the first pressure surface 121 opposite to the first suction surface 122. This design helps to weaken the tip vortex intensity, thereby suppressing the vortex-induced vibration of the propeller 200, effectively improving the acoustic performance of the propeller 200, and reducing underwater noise pollution from the ship 400.

[0076] like Figure 7 and Figure 8As shown, comparing the flow field characteristics of propeller tip vortices in related technologies with the flow field characteristics of the blade tip 130 in this invention, we can see the vortex with a narrow guide edge on the original blade tip suction surface (second suction surface 134) and the reflected flow from the blade tip suction surface. In this invention, when the fluid passes through the blade tip annular structure (open annular structure 132), the flow smoothly diffuses towards the top of the blade ring (top of the open annular structure 132). The blade shape, bent towards the pressure surface, causes the vortex to diffuse around the periphery, greatly suppressing the vortex shedding from the blade tip guide edge, and the vortex intensity also decreases on the annular surface. When the vortex reaches the tail of the open annular structure 132, the second suction surface 134 has already smoothly transitioned to the side of the first pressure surface 121 away from the first suction surface 122, and the vortex intensity is also greatly reduced. The flow field flows smoothly out along the blade tip of the open annular structure 132, and the previous vortex shedding is basically suppressed.

[0077] In some embodiments, optionally, the inner contour of the cross-section of the open annular structure 132 is an arc, and the central angle corresponding to the arc is 175 degrees to 185 degrees.

[0078] In other words, the open annular structure 132 bends toward the first pressure surface 121 at an angle of 175 to 185 degrees. This design ensures that at least a portion of the second suction surface 134 is located on the side of the first pressure surface 121 away from the first suction surface 122, which helps to weaken the tip vortex intensity and suppress the vortex-induced vibration of the propeller 200.

[0079] In one specific embodiment, the central angle corresponding to the arc is 180 degrees, that is, the bending angle is 180 degrees.

[0080] In some embodiments, the radial dimension of the blade 100 is optionally a first dimension, and the radial dimension of the open annular structure 132 along the blade 100 is a second dimension, which is 4% to 6% of the first dimension.

[0081] This design ensures that the open annular structure 132 is provided without changing the main blade shape of the propeller 200, and at least a portion of the open annular structure 132 is bent toward the first pressure surface 121, which helps to suppress eddies and reduce the vibration noise of the propeller 200.

[0082] In one specific embodiment, the second dimension is 5% of the first dimension.

[0083] In one specific embodiment, the blade tip 130 of the blade 100 is horizontally cut off at a first length (0.025m, 5% of the radial dimension of the blade 100); an annular semi-tubular structure (open annular structure 132) with the same line shape as the cut surface is spliced ​​with the cut surface, so that the annular semi-tubular structure surrounds the thrust surface of the blade 100 by 180° (bending angle of 180 degrees); the blade edge is appropriately smoothed; the surrounding diameter of the annular semi-tubular structure is 0.025m.

[0084] In one embodiment of the invention, such as Figure 3 and Figure 4 As shown, the propeller 200 includes a central shaft 210 and blades 100 in any of the above embodiments, with the blade root 110 of the blade 100 connected to the central shaft 210.

[0085] Since the propeller 200 includes any of the blades 100 in the first aspect described above, it has the beneficial effects of any of the above embodiments, which will not be repeated here.

[0086] Optionally, the blade root 110 and the central shaft 210 are detachably connected, which facilitates the disassembly and assembly of the blade 100 by the staff and is beneficial for maintenance or replacement.

[0087] In one specific embodiment, the blade root 110 and the central shaft 210 are detachably connected by a key connection or an interference fit. Furthermore, when the blade root 110 and the central shaft 210 are connected, the blade root 110 and the central shaft 210 are relatively fixed in the circumferential direction so that the central shaft 210 transmits torque to the blade 100.

[0088] It should be noted that the number of blades 100 can be two or more, and the number of blades 100 can be flexibly set according to actual needs.

[0089] In a specific embodiment, such as Figure 3 and Figure 4 As shown, there are 4 blades 100. The radial dimension of the propeller 200 is 1m.

[0090] In one embodiment of the invention, such as Figure 5 As shown, the propulsion device 300 includes a drive unit 310 and a propeller 200 as described above. The propeller 200 is connected to the drive unit 310.

[0091] Since the power propulsion device 300 includes the propeller 200 mentioned in the second aspect above, it has the beneficial effects of the above-mentioned technical solution, which will not be elaborated here.

[0092] In one specific embodiment, the driving element 310 is a drive motor or a drive motor.

[0093] Optionally, the power propulsion device 300 also includes a reduction gear, which is located between the propeller 200 and the drive unit 310 and serves to transmit torque and match the rotational speed.

[0094] In one embodiment of the invention, such as Figure 6 As shown, the vessel 400 includes a hull 410 and a propulsion device 300 as described in the above technical solution. The propulsion device 300 is connected to the drive unit 310.

[0095] Since the ship 400 includes the power propulsion device 300 mentioned in the third aspect above, it has the beneficial effects of the above technical solution, which will not be elaborated here.

[0096] In this invention, the terms "first," "second," and "third" are used for descriptive purposes only and should not be construed as indicating or implying relative importance; the term "multiple" refers to two or more unless otherwise explicitly defined. The terms "install," "connect," "link," and "fix" should be interpreted broadly. For example, "connect" can be a fixed connection, a detachable connection, or an integral connection; "link" can be a direct connection or an indirect connection through an intermediate medium. Those skilled in the art can understand the specific meaning of the above terms in this invention according to the specific circumstances.

[0097] In the description of this invention, it should be understood that the terms "upper," "lower," "left," "right," "front," "rear," etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. They are only for the convenience of describing this invention and simplifying the description, and do not indicate or imply that the device or unit referred to must have a specific orientation or be constructed and operated in a specific orientation. Therefore, they should not be construed as limitations on this invention.

[0098] In the description of this specification, the terms "one embodiment," "some embodiments," "specific embodiment," etc., refer to a specific feature, structure, material, or characteristic described in connection with that embodiment or example, which is included in at least one embodiment or example of the present invention. In this specification, the illustrative expressions of the above terms do not necessarily refer to the same embodiment or example. Furthermore, the specific features, structures, materials, or characteristics described may be combined in any suitable manner in one or more embodiments or examples.

[0099] The above are merely preferred embodiments of the present invention and are not intended to limit the present 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 blade, characterized in that, The blade comprises a root (110), a blade body (120), and a tip (130) connected in sequence. The blade (120) has a first pressure surface (121) and a first suction surface (122) arranged opposite to each other. During the rotation of the blade, the fluid can flow from the position of the first pressure surface (121) to the position of the first suction surface (122). At least a portion of the leaf tip (130) bends toward the first pressure surface (121); The leaf tip (130) includes: The leaf tip body (131) is connected to the leaf body (120); An open annular structure (132) is provided at one end of the leaf tip body (131) away from the leaf body (120), and at least a portion of the open annular structure (132) is bent toward the first pressure surface (121); The open annular structure (132) has a second pressure surface (133) and a second suction surface (134) arranged opposite to each other. The second pressure surface (133) is connected to the first pressure surface (121) and located on the same side of the blade. The second suction surface (134) is connected to the first suction surface (122) and located on the same side of the blade. At least a portion of the second suction surface (134) is disposed on the side of the first pressure surface (121) opposite to the first suction surface (122); The inner contour of the cross-section of the open annular structure (132) is an arc, and the central angle corresponding to the arc is 175 degrees to 185 degrees. The open ring structure (132) and the leaf tip body (131) are either an integral structure or a separate structure, and the open ring structure (132) is connected to the leaf tip body (131). The radial dimension of the blade is a first dimension, and the radial dimension of the open annular structure (132) along the blade is a second dimension, which is 4% to 6% of the first dimension.

2. A propeller, characterized in that, include: Central axis (210); The blade as claimed in claim 1, wherein the blade root (110) is connected to the central shaft (210).

3. A power propulsion device, characterized in that, include: Drive unit (310); The propeller as described in claim 2 is connected to the drive unit (310).

4. A ship, characterized in that, include: Hull (410); The power propulsion device as described in claim 3 is disposed on the hull (410).

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