CN115583326A

CN115583326A - Fair-fin energy-saving hub cap

Info

Publication number: CN115583326A
Application number: CN202211293108.5A
Authority: CN
Inventors: 刘洋浩; 黄少锋; 孙海素
Original assignee: Shanghai Sidarui Ship Sea Engineering Service Co ltd
Current assignee: Shanghai Sidarui Ship Sea Engineering Service Co ltd
Priority date: 2022-10-21
Filing date: 2022-10-21
Publication date: 2023-01-10

Abstract

The invention discloses a sley fin energy-saving hub cap which is arranged behind a propeller of a ship; the heat exchanger comprises side walls which are distributed annularly and a bottom plate which is used for sealing an opening at the rear end of each side wall, wherein a plurality of fins are arranged on the outer surfaces of the side walls; the least common multiple of the number of the fins and the number of the blades of the propeller is not less than 20; the side wall, the bottom plate and the fins are integrally formed. The invention can obtain good energy-saving benefit, and has simple structure and convenient manufacture.

Description

Energy-saving hub cap with comb fins

Technical Field

The invention relates to the technical field of ships, in particular to a slenderness fin energy-saving hub cap.

Background

In all the civil operation ships, the propeller is the most widely applied propulsion form. On the premise of taking the propeller as a propeller, the energy-saving principle of the ship energy-saving device is divided into three categories from the hydrodynamic characteristics. Firstly, the forward flow of the propeller is changed, so that the efficiency of the whole propulsion system is improved, such as a propeller front guide vane, a propeller front guide pipe and the like; secondly, the design forms of the propeller, such as trim optimization, a new blade section design form and the like, are changed; thirdly, the rotary energy loss in the propeller wake vortex is recovered.

The existing energy-saving device for recovering the energy loss of the wake vortex mainly comprises a hub cap fin, a twisted rudder, a rudder attached fin and the like. The structure of the trailing vortex recovery energy-saving device such as the twisted rudder, the rudder fin and the like is complex, the process requirement is high, the maintenance is difficult, and meanwhile, the existing energy-saving device is added with a new structure on the basis of the original structure, so that the corresponding cost is also increased; the hub cap fins and the like are complex in design, sensitive to phase angle difference between the hub cap fins and the propeller, and limited in application conditions.

In the prior art, a device for recovering the rotation energy of the propeller wake vortex is mainly divided into two attached forms.

The first kind of attached body is hub cap fin, and the energy-saving attached body is fixed at the tail end of a propeller shaft, rotates along with the propeller, and disturbs water flow through blades equal to the propeller on the energy-saving attached body to achieve the purpose of saving energy. The energy-saving target is mainly realized by the upper blade, the relative position between the blade and the propeller blade needs to be fully considered in the blade design process, when the relative position is ideal, a relatively considerable energy-saving effect can be generated, if the relative position is not reasonable enough, the energy-saving effect can be greatly reduced, meanwhile, errors exist among forecasting, testing and real ship operation, and the errors can also be influenced by the relative position, so the design difficulty is high. Usually, the diameter of the blade can reach 0.25 to 0.35 times of the diameter of the propeller, and a certain thickness is needed for the longer blade to ensure the reliable strength, which undoubtedly increases the design difficulty and the material cost. According to test measurement results, the energy-saving effect of the energy-saving appendage is usually about 1%.

The second is an appendage structure attached to the rudder, such as a rudder ball, twisted rudder, etc. The structure is a fixed structure and does not need to rotate, so that power driving is not needed, the main principle of energy saving is that the additional thrust borne by the appendage when the appendage rotates in the wake of the propeller is larger than the resistance caused by the appendage, or the resistance received by the rudder is reduced due to the appendage, but the appendage is added or the shape is changed to adapt to the rotating wake of the propeller. However, the energy-saving device is rigidly fixed on the rudder blade, and the energy-saving effect can be captured by adopting direct navigation during test and measurement, however, in the real ship navigation process, in order to balance the deflection effect of the propeller and the navigation requirements such as steering, the rudder needs to be steered by a certain rudder angle to operate, and under the working conditions, the energy-saving device fails, and the additional body resistance is increased on the basis of failure in a less-added state. Therefore, the energy-saving effect of the energy-saving device is discounted on the basis of test measurement by comprehensively considering the energy-saving device. In addition, because the structure of the rudder is the characteristic of the external skin of the internal skeleton and the rigid connection form of the rudder, the structural design form which is compatible with the strength also becomes one of the limiting factors. The energy-saving effect of the energy-saving device in the model test stage is about 0.5-1%.

In addition, due to the design characteristics of the two types of complicated wake vortex recovery energy-saving devices, the design period is long, and a large amount of calculation verification is needed, so that a relatively ideal scheme is obtained. This is also one of the drawbacks of the prior art.

Disclosure of Invention

The present invention is directed to overcoming the above-mentioned deficiencies of the prior art and providing a slenderer energy saving hub cap.

The invention solves the technical problems through the following technical scheme:

a sley-ratio fin energy-saving hub cap is arranged behind a propeller of a ship; the heat exchanger comprises side walls and a bottom plate, wherein the side walls are distributed annularly, the bottom plate is used for sealing an opening at the rear end of each side wall, and a plurality of fins are arranged on the outer surfaces of the side walls; the least common multiple of the number of the fins and the number of the blades of the propeller is not less than 20; the side wall, the bottom plate and the fins are integrally formed.

The maximum distance from the end part of the fin to the rotating shaft of the propeller is 0.1-0.25 times of the maximum distance from the end part of the blade of the propeller to the rotating shaft of the propeller.

The number of fins is not less than the number of blades of the propeller.

The side wall and the bottom plate form a circular truncated cone, and the area of the bottom plate is smaller than that of the circular area at the front end of the side wall.

The intersecting line of the fins and the side wall is not parallel to the central axis of the circular truncated cone formed by the side wall and the bottom plate.

The fins are evenly distributed along the circumference of the side wall.

The distance between adjacent fins is equal.

The side wall and the bottom plate are enclosed to form an accommodating cavity for accommodating the hydraulic nut.

The front end of the side wall is provided with a bolt groove; the bolt grooves are distributed along the outer surface of the side wall in the circumferential direction.

And bolt holes are formed in the wall of the bolt groove.

The invention has the beneficial effects that: the sley ratio fin energy-saving hub cap is fixed behind a propeller through bolts, is rigidly connected with the propeller and synchronously rotates, and can effectively protect a hydraulic nut in the hub cap; the fins are arranged on the hub cap, and the wake flow at the hub part of the propeller is trimmed, so that about 1.5% of energy-saving benefit can be obtained, and the aim of saving energy is fulfilled.

Drawings

Fig. 1 is a perspective view of a preferred embodiment of the present invention.

Fig. 2 is a rear view of the preferred embodiment of the present invention.

Fig. 3 is a front view of the preferred embodiment of the present invention.

Detailed Description

The present invention will be more clearly and completely described in the following description of preferred embodiments, taken in conjunction with the accompanying drawings.

As shown in fig. 1, 2 and 3, a comby fin-type energy saving hub cap is provided behind a propeller (not shown) of a ship; it comprises circumferentially distributed side walls 10 and a bottom plate 20 for closing the rear end opening of the side walls.

The side wall 10 and the bottom plate 20 are enclosed into a circular truncated cone shape, and the area of the bottom plate 20 is smaller than the circular area of the front end of the side wall.

The side walls 10 and the bottom plate 20 enclose a receiving chamber for receiving a hydraulic nut.

The front end of the side wall 10 is provided with a bolt groove 11; the bolt grooves 11 are circumferentially distributed along the outer surface of the side wall. The wall of the bolt slot 11 is provided with a bolt hole 12.

The outer surface of the sidewall 10 is provided with a plurality of fins 30. The side walls 10, the bottom plate 20 and the fins 30 are integrally formed.

The fins 30 are evenly distributed along the circumference of the side wall. The distance between adjacent fins is equal.

The intersecting line of the fin 30 and the side wall 10 is not parallel to the central axis of the circular truncated cone formed by the side wall 10 and the bottom plate 20. That is, the fins extend obliquely at the outer surface of the side wall.

The least common multiple of the number of fins 30 and the number of blades of the propeller is not less than 20. The number of fins 30 is not less than the number of blades of the propeller.

The maximum distance from the end of the fin 30 to the rotating shaft of the propeller is 0.1 to 0.25 times the maximum distance from the end of the blade of the propeller to the rotating shaft of the propeller.

The invention relates to a farrow fin energy-saving hub cap which is a marine propeller rear energy-saving device. The slenderness fin energy-saving hub cap is rigidly fixed with the propeller and synchronously operates with the propeller. The rotary hub vortex generated by the propeller during working can be recovered by the comb-ratio fin energy-saving hub cap, so that the energy-saving effect is obtained.

The slenderness fin energy-saving hub cap is an integrally formed structure by adopting a casting process. The holding chamber that lateral wall and bottom plate enclose is used for holding hydraulic nut, protects whole shafting end.

The least common multiple of the number of the fins and the number of the blades of the propeller is not less than 20. For example, for a 3-blade propeller, the number of fins is not less than 7; for 4-blade propellers, the number of fins is not less than 7; for a 5-blade propeller, the number of fins is not less than 6, and so on. In one embodiment, a 4-blade propeller is matched with 10 blades, and the least common multiple of the blades is 20.

The front end part of the comb-fin energy-saving hub cap is provided with a bolt groove and a bolt hole, and when the comb-fin energy-saving hub cap is connected with the propeller, the bolt is fixed on the small end face of the hub of the propeller through the bolt hole.

From the perspective of propeller hub vortex recovery, the present invention can achieve energy savings by reducing hub vortex rotational energy losses. When the propeller runs, the propeller rotates and advances to cause a spiral wake vortex of the propeller hub, the spiral wake vortex flows downstream to the vicinity of the propeller hub, and the fins of the fin-saving hub cap are acted by the wake vortex or generate a force pointing to the advancing direction or generate a torque same as the rotating direction of the propeller, and the force or the torque can generate an energy-saving effect.

Through numerical analysis and experimental research, the comb of the invention can obtain about 1.5% of energy-saving benefit compared with a fin energy-saving hub cap, and is more effective than the same type wake vortex recovery type energy-saving appendage.

The combined type fin energy-saving hub cap is simple in structure compared with a fin energy-saving hub cap, and meanwhile, due to the relative position principle, the problem of relative position adaptation of the combined type fin energy-saving hub cap and propeller blades does not exist, and therefore the mounting angle does not need to be considered during design.

The invention relates to a comb energy-saving hub cap with fins, wherein the fins rotate along with a propeller during operation, and the maximum distance from the end parts of the fins to a rotating shaft of the propeller is 0.1-0.25 times of the maximum distance from the end parts of blades of the propeller to the rotating shaft of the propeller. That is, the rotating diameter of the comb of the present invention is only in the range of 0.1 to 0.25 times the rotating diameter of the propeller than the fin energy saving hub cap, and has a better strength level than the conventional hub cap fin longer blade form. The defect that the structural form and the design flow are complex in the prior art is overcome.

The sley ratio fin energy-saving hub cap is fixed behind the propeller through bolts, and the connection form of fixing the sley ratio fin energy-saving hub cap on the rudder blade, such as a ball hiding form, a twisted rudder and the like, is avoided, so that the sley ratio fin energy-saving hub cap can continuously and stably work right behind the propeller to recover energy.

Compared with a fin energy-saving hub cap, the fin energy-saving hub cap has the characteristics of relatively easy design, simple structure, unique shape and no need of phase angle adaptation with a propeller, can also obtain an energy-saving effect similar to that of other energy-saving devices of the same type, simultaneously solves the four defects of limited relative installation position, long design period, complex structure, incapability of working in an energy-saving state for a long time and the like, and is a more reasonable novel energy-saving device.

While specific embodiments of the invention have been described above, it will be understood by those skilled in the art that this is by way of example only, and that the scope of the invention is defined by the appended claims. Various changes and modifications to these embodiments may be made by those skilled in the art without departing from the spirit and scope of the invention, and these changes and modifications are within the scope of the invention.

Claims

1. A sley-ratio fin energy-saving hub cap is arranged behind a propeller of a ship; the novel LED lamp is characterized by comprising side walls which are distributed annularly and a bottom plate which is used for sealing an opening at the rear end of each side wall, wherein a plurality of fins are arranged on the outer surfaces of the side walls; the least common multiple of the number of the fins and the number of the blades of the propeller is not less than 20; the side wall, the bottom plate and the fins are integrally formed.

2. The comb ratio fin energy saving hub cap of claim 1, wherein the maximum distance from the fin end to the rotation axis of the propeller is 0.1 to 0.25 times the maximum distance from the blade end of the propeller to the rotation axis of the propeller.

3. The comb-ratio fin energy saving hub cap of claim 1, wherein the number of fins is not less than the number of blades of the propeller.

4. The comb-ratio fin energy saving hub cap of claim 1, wherein the side walls and the bottom plate define a frustoconical shape, the bottom plate having an area less than the circular area of the front ends of the side walls.

5. The comb-ratio fin energy-saving hub cap of claim 4, wherein the intersection of the fins with the side walls is not parallel to a central axis of the truncated cone defined by the side walls and the base plate.

6. The comb-ratio fin energy saving hub cap of claim 1, wherein the fins are evenly distributed along the circumference of the sidewall.

7. The comb ratio fin energy saving hub cap of claim 6, wherein the distance between adjacent fins is equal.

8. The comb-ratio fin energy saving hub cap of claim 1, wherein the side walls and the bottom plate enclose a receiving cavity for receiving a hydraulic nut.

9. The comb-ratio fin energy saving hub cap of claim 1, wherein the front end of the side wall is provided with a bolt slot; the bolt grooves are distributed along the outer surface of the side wall in the circumferential direction.

10. The comb-ratio fin energy saving hub cap of claim 9, wherein the bolt slot has a bolt hole formed in a wall of the bolt slot.