Annular fin blade propeller cap turbine and hull

Abstract

The invention relates to the technical field of energy-saving devices in the field of ship engineering, and discloses an annular fin blade propeller cap turbine and a ship hull. The annular fins are uniformly distributed on the periphery of the light cap; the wing-shaped rotating direction of the annular fin blades is consistent with that of the propeller; the annular fin blades and the light caps form an annular closed area, and tip leakage is prevented. The annular fin tip prevents tip discharge, flow fields of the front fin blade and the rear fin blade are separated in advance near the annular fin tip, and cannot be fused to form vortex after being transversely scattered by the fin tip, so that the energy-saving effect is enhanced.

Description

Technical Field

[0001] The present invention relates to the technical field of energy-saving devices in the field of ship engineering, and particularly relates to an annular fin blade hubcap turbine and a hull. Background Art

[0002] A propeller is installed at the tail of a hull and is connected to a main engine through a propeller shaft. The main engine consumes fuel and provides power for the propeller to rotate. The propeller can convert the rotational force into a linear propulsion force, thereby driving the ship to overcome resistance and move forward.

[0003] The propeller rotates behind the ship and pushes the ship forward. Due to the superposition of its velocity vectors, the absolute velocity is relatively large, and a large amount of eddy currents will leak out at the blade root. The eddy currents develop towards the rear of the ship and form a hub vortex through the hubcap. If not suppressed, it is easy to form hub vortex cavitation, consume the power of the main engine, and cause noise hazards, affecting the economy and comfort of the ship.

[0004] There are various ways to eliminate the propeller hub vortex. Installing a hubcap turbine (also known as a hub cap fin, vortex elimination fin) is a common one. By arranging fin blades equivalent to the number of propeller blades on the propeller hubcap, and through hydrodynamic calculations, setting a certain pitch angle for the fin blades and adjusting the fin blade positions to keep a fixed relative angle with the propeller blades all the time, it is possible to effectively break up the eddy currents generated by the propeller and accelerate their dissipation, reduce the consumption of the main engine power, and thus achieve the purpose of energy saving.

[0005] Although the hubcap turbine can reduce energy loss by breaking up eddy currents, due to the relatively large chord length in the spanwise direction of the fin blades and a certain pitch angle, it will also generate a certain torque during rotation, resulting in energy consumption; moreover, for conventional hubcap turbine fin blades, there is leakage at the tip, and the flow fields on the pressure surface and suction surface of the fin blades exchange at the tip, which will also generate eddy currents of a certain intensity, also resulting in energy loss; in addition, the number of fin blades of a conventional hubcap turbine is generally the same as the number of propeller blades. During installation, special attention needs to be paid to the relative positions of the fin blades and the propeller blades to meet the requirements of the design angle, and there is a risk of misalignment and misinstallation.

[0006] In summary, conventional hubcap turbines have various inherent problems and there is a large room for optimization. There is an urgent need for a hubcap turbine that reduces energy loss and cuts down on energy consumption. Summary of the Invention

[0007] In order to solve the above technical problems, the purpose of the present invention is to provide an annular fin blade hubcap turbine and a hull.

[0008] As the first aspect of the present invention, the present invention provides an annular fin blade hubcap turbine, including a smooth cap, one end of which is fixedly connected to the propeller of the hull;

[0009] There are multiple annular fin blades, which are evenly distributed on the outer periphery of the light cap; the helical direction of the airfoil of the annular fin blades is the same as that of the propeller; the annular fin blades and the light cap form an annular closed area to prevent tip leakage.

[0010] According to the present invention, further, each of the annular fin blades includes a front fin, a rear fin, and an annular fin tip with both ends respectively connected to the corresponding front fin or rear fin; the other ends of the front fin and the rear fin are both fixedly connected to the outer peripheral surface of the light cap; the groove of the annular fin tip faces the direction of the outer peripheral surface of the light cap.

[0011] According to the present invention, further, the average pitch angle of the front fin and the rear fin is the same as the pitch angle at 0.7R of the propeller blade, and the front fin and the rear fin are arranged in the same pitch plane.

[0012] According to the present invention, further, the annular fin blades and the propeller blades always maintain a fixed relative angle.

[0013] According to the present invention, further, the diameter of the annular fin blade propeller cap turbine is 28% of the diameter of the corresponding propeller, and the maximum chord length of the front fin, the rear fin, and the annular fin tip of the annular fin blade does not exceed the root of the propeller.

[0014] According to the present invention, further, the number of the annular fin blades is set to 3 - 8.

[0015] According to the present invention, further, one end of the light cap is integrally formed with an annular connecting portion, and fixing holes are formed on the end face of the annular connecting portion. A fixing member passes through the fixing holes and is fixedly connected to the propeller.

[0016] According to the present invention, further, the diameter of the annular connecting portion corresponds to the diameter of the light cap, and relief holes are formed on the outer peripheral surface of the annular connecting portion.

[0017] According to the present invention, further, a lifting hole is formed on the end face of the side of the light cap away from the propeller.

[0018] As the second aspect of the present invention, a hull includes a propeller arranged at the tail of the hull. The annular fin blade propeller cap turbine is fixedly installed on the end face of the propeller and rotates together with the propeller to break up the eddy current generated by the propeller.

[0019] Compared with the prior art, the beneficial effects of the present invention are as follows:

[0020] 1. The annular fin tips of the present invention prevent tip leakage. The flow fields of the front fin blades and the rear fin blades are separated in advance near the annular fin tips. After being transversely broken up by the fin tips, they will not fuse again to form eddy currents, enhancing the energy-saving effect; 2. The spanwise chord lengths of the front fin blades and the rear fin blades of the present invention are both small, and the torque caused by the fin blades is very small and will not affect the energy-saving effect. At the same time, the front fin blades and the rear fin blades will break up the eddy current generated by the propeller twice, and the eddy current elimination and energy-saving effect is more obvious.

[0021] 3. The number of fin blades of the present invention is no longer limited to being equal to the number of propeller blades. Since the torque increase caused by a single fin blade of the propeller blade is not significant, the number of fin blades can exceed the number of propeller blades without causing a large torque increase and energy consumption. The circumferential position of the fin blades is no longer restricted, which can avoid the risk of installation errors and save installation costs. BRIEF DESCRIPTION OF THE DRAWINGS

[0022] Figure 1 is an assembly schematic diagram of the propeller cap turbine and the propeller of the present invention;

[0023] Figure 2 is an isometric schematic diagram of the annular fin blade propeller cap turbine of the present invention from the first perspective;

[0024] Figure 3 is a schematic diagram of a single annular fin blade (including the light cap) of the present invention;

[0025] Figure 4 is a schematic diagram of the annular fin blade propeller cap turbine of the present invention from the first perspective;

[0026] Figure 5 is a schematic diagram of the annular fin blade propeller cap turbine of the present invention from the second perspective;

[0027] Figure 6 is an isometric schematic diagram of the annular fin blade propeller cap turbine of the present invention from the second perspective.

[0028] Among them, the reference numerals are as follows: 10 - propeller, 20 - light cap, 21 - bolt hole, 22 - lifting hole, 23 - relief hole, 30 - annular fin blade, 31 - front fin, 32 - rear fin, 33 - annular fin tip, 40 - annular connection part. DETAILED DESCRIPTION OF THE EMBODIMENTS

[0029] The following further details the technical solutions proposed by the present invention in conjunction with the accompanying drawings and specific embodiments. According to the following description, the advantages and features of the present invention will be clearer. It should be noted that the accompanying drawings are all in a very simplified form and use non-precise scales, only for the purpose of facilitating and clearly assisting in explaining the objectives of the embodiments of the present invention.

[0030] This embodiment provides an annular fin blade propeller cap turbine, as shown in Figure 1 and Figure 2As shown in the figure, it is fixedly installed at the end of the propeller 10 on the hull through bolts, and the two rotate together to eliminate the propeller hub vortex. It includes a fairing 20, which is cylindrical. One end of the fairing 20 is formed with a bolt hole 21. The bolt passes through the bolt hole 21 and is fixedly connected to the propeller 10. Its outer peripheral surface is a smooth surface, and a plurality of annular fin blades 30 are evenly distributed along its circumferential direction. The airfoil rotation direction of the annular fin blades 30 is the same as that of the propeller 10. During the rotation of the propeller 10, the annular fin blades 30 and the blades of the propeller 30 always maintain a fixed relative angle, which is convenient for dispersing the vortex generated by the propeller and reducing the generation of hub vortex cavitation. Among them, the diameter of the fairing 20 is the same as the small end diameter of the propeller 10. The entire fairing 20 has an internal cavity, and the length of the fairing 20 is based on the arrangement of the annular fin blades. To ensure the overall strength of the propeller cap turbine, the entire propeller cap turbine should be integrally cast, and the external dimensions are ensured by cutting.

[0031] Specifically, as Figure 3 and Figure 4 shown, each annular fin blade 30 includes a front fin 31, a rear fin 32, and an annular fin tip 33 with both ends respectively connected to the corresponding front fin 31 or rear fin 32. The other ends of the front fin 31 and the rear fin 32 are both fixedly connected to the outer peripheral surface of the fairing 20. The groove of the annular fin tip 33 faces the direction of the outer peripheral surface of the fairing 20, which prevents the tip leakage, reduces the energy loss, and avoids the exchange of the flow fields on the pressure surface and the suction surface of the existing fin blades at the tip, generating vortices.

[0032] Furthermore, a relief hole 23 is also formed on one side of the fairing 20 where the bolt hole 21 is formed. Through the relief hole 23 and the bolt hole 21, the propeller cap turbine can be fixed to the small end of the propeller hub of the propeller 10 with bolts. A lifting hole 22 is formed on the surface of the other end of the fairing 20, which is convenient for the lifting device to be fixed to it, realizing the lifting and installation of the propeller cap turbine.

[0033] In the embodiment of the present application, as Figure 1 、 Figure 4 and Figure 5 shown, the diameter of the propeller cap turbine is 28% of the diameter of the corresponding propeller 10. The airfoil of each annular fin blade 30 is NACA0016. The maximum chord length of the front fin 31, the rear fin 32, and the annular fin tip 33 of the annular fin blade does not exceed the root of the propeller 10. The average pitch angle of the front fin 31 and the rear fin 32 is the same as the pitch angle at 0.7R of the blade of the propeller 10. The front fin 31 and the rear fin 32 are arranged in the same pitch plane. The number of the annular fin blades 30 is set to 3 to 8 blades, and the number of blades is based on the best energy-saving effect calculated numerically.

[0034] The number of bolt holes 21 is twelve, which are evenly distributed along the circumferential direction of the end face of the fairing 20 and are stably connected to the propeller 10.

[0035] In the embodiment of the present application, as Figure 6As shown in the figure, an annular connecting portion 40 is integrally formed at the connecting end of the light cap 20 and the propeller 10. The diameter of the annular connecting portion 40 corresponds to the diameter of the light cap 20. A bolt hole 21 is formed on the end face of the annular connecting portion 40 facing the propeller 10, and a relief hole 23 is formed on the outer peripheral surface of the annular connecting portion 40.

[0036] The working principle of the present invention is as follows: The propeller cap turbine and the propeller 10 rotate simultaneously. The front fin 31 and the rear fin 32 can break up the hub vortex formed by the rotation of the propeller 10 twice, increasing the vortex elimination efficiency; the spanwise chord lengths of the front fin 31 and the rear fin 32 are not large, and the torque increase is small, without causing secondary power consumption; the annular fin tip 33 is an annular tip, blocking the flow field exchange, so that the propeller cap turbine does not generate additional tip vortices, increasing the energy-saving effect.

[0037] The above description is only a description of the preferred embodiments of the present invention, and does not limit the scope of the present invention in any way. Any changes and modifications made by those of ordinary skill in the field of the present invention based on the above disclosure are within the scope of protection of the claims.

Claims

1. A ring-shaped fin blade cap turbine, characterized in that: include, A light cap, one end of which is fixedly connected to the propeller of the hull; There are multiple annular fin blades evenly distributed on the periphery of the smooth cap; the rotation direction of the annular fin blade airfoil is consistent with the rotation direction of the propeller; the annular fin blade and the smooth cap form an annular closed area to prevent tip leakage.

2. The annular fin blade turbine according to claim 1, characterized in that: Each of the annular fin blades includes a front fin, a rear fin, and an annular fin tip with both ends connected to the corresponding front fin or rear fin; the other ends of the front fin and the rear fin are fixedly connected to the outer peripheral surface of the light cap; the groove of the annular fin tip faces the outer peripheral surface of the light cap.

3. The annular fin blade turbine according to claim 2, characterized in that: The average pitch angle of the front fin and the rear fin is consistent with the pitch angle of the propeller blade at 0.7R, and the front fin and the rear fin are arranged in the same pitch plane.

4. The annular fin blade turbine according to claim 1, characterized in that: The annular fin blade and the propeller blade always maintain a fixed relative angle.

5. The annular fin blade turbine according to claim 2, characterized in that: The diameter of the annular fin blade propeller cap turbine is 28% of the corresponding propeller diameter, and the maximum chord length of the front fin, the rear fin, and the annular fin tip of the annular fin blade does not exceed the root of the propeller.

6. The annular fin blade turbine according to any one of claims 1 to 5, characterized in that: The number of the annular fins is set to 3-8.

7. The annular fin blade turbine according to claim 1, characterized in that: An annular connecting portion is integrally formed at one end of the light cap, a fixing hole is formed on the end surface of the annular connecting portion, and a fixing piece passes through the fixing hole and is fixedly connected to the propeller.

8. The annular fin blade turbine according to claim 7, characterized in that: The diameter of the annular connecting portion corresponds to the diameter of the light cap, and a lightening hole is formed on the outer peripheral surface of the annular connecting portion.

9. The annular fin blade turbine according to claim 1, characterized in that: A hoisting hole is formed on an end surface of the light cap which is away from the propeller.

10. A hull, comprising a propeller arranged at the stern of the hull, characterized in that: The annular fin blade cap turbine as described in any one of claims 1-9 is fixedly mounted on the end face of the propeller, rotates together with the propeller, and breaks up the vortex generated by the propeller.

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