CN114802676A

CN114802676A - High-performance combined rudder and design method

Info

Publication number: CN114802676A
Application number: CN202210299322.5A
Authority: CN
Inventors: 姚智衡; 姚奉
Original assignee: Yichang Yifan Ship Design Co ltd
Current assignee: Yichang Yifan Ship Design Co ltd
Priority date: 2022-03-25
Filing date: 2022-03-25
Publication date: 2022-07-29
Anticipated expiration: 2042-03-25
Also published as: CN114802676B

Abstract

The invention provides a high-performance combined rudder and a design method thereof.A rudder device assembly comprises a first rudder device and a second rudder device; the first rudder device comprises a first rudder blade, the first rudder blade is arranged at the bottom end of a first rudder stock assembly, the first rudder stock assembly is rotatably arranged in a ship body rudder device platform, and the first rudder stock assembly is connected with a steering engine for providing steering power through a first rudder handle; the second rudder device comprises a second rudder blade, the second rudder blade is installed at the bottom end of the second rudder stock assembly, the second rudder stock assembly is installed inside the ship rudder device platform and is arranged in parallel with the central line of the first rudder stock assembly, and the top end of the second rudder stock assembly is fixedly installed on the rudder stock fixing structure in a limiting mode through a second rudder stock. The combined rudder can stabilize the high-efficiency technology of the energy-saving attached body and the flap rudder, and is generated on a sailing ship for a long time, the combination of the static rudder and the dynamic rudder forms a combined rudder with a large flap, the rudder of the large flap reduces the steering frequency to a great extent, and the energy-saving effect is generated at the same time.

Description

High-performance combined rudder and design method

Technical Field

The invention relates to the technical field of ship energy conservation, in particular to a high-performance combined rudder and a design method.

Background

The development and application of ship energy-saving technology and high-performance rudders are very extensive and mature, the space for further diving is very limited, and continuous efforts are needed in the industry.

The efficiency of the ship rudder and the efficiency of the ship are mutually restricted and complement each other, the overweight rudder efficiency or propulsion efficiency can bring the loss of the other side, the efficiency of the rudder and the propulsion efficiency of the ship are optimally designed, the maneuverability and the rapidity of the ship are fully considered, the contradiction between the high rudder efficiency and the rapidity is further balanced, and a brand-new high-performance combined rudder needs to be developed.

At present, the energy-saving technology in rudder design in the field of ships is widely adopted mainly as follows: 1. the energy-saving rudder ball mainly has the energy-saving mechanism that the rudder ball fills the space of a low-pressure area behind a propeller hub cap, has good rectification effect on water flow behind a propeller, and eliminates the vortex of the propeller hub; the hub vortex forms a low-pressure area behind the hub cap, the thrust of the propeller is reduced to a certain extent, and after the rudder ball is arranged, water flow behind the hub of the propeller is forced to flow along the surface of the rudder ball, so that the water flow near the rudder ball cannot rotate strongly, the effects of rectifying and enhancing the thrust are achieved, and the purpose of saving energy is achieved. 2. The rudder is attached with a thrust fin: the thrust fin is usually used in combination with a rudder ball energy-saving technology, is arranged on two sides of a corresponding central line of a rudder blade shaft system, and is also mainly used for absorbing the rotation energy of the propeller wake flow to achieve the purpose of enhancing the thrust of the propeller, or recovering the rotation energy of the propeller wake flow, and the rudder attached thrust fin has a large wingspan and is easy to hook sundries, so that the probability of extra maintenance cost is high. This is one of the factors that limit its widespread use.

The two rudder-attached energy-saving technologies are simple in structure and convenient to install, are widely adopted by the ship industry, can achieve a good energy-saving effect when a ship sails forward at a few steering angles, and are good in ship sailing effect in inland rivers and lakes with wide sea and water area environments. However, when the inland river ship is in a beaches with multiple flow urgency, the ship density is high, the ship is frequently steered, when the steering is performed from more than 0-35 degrees, the rudder blade is additionally provided with the rudder ball, the thrust fin forms an included angle behind the propeller, particularly when the ship is steered at a large angle, the rudder ball and the rudder additional thrust fin are positioned behind the transom of the propeller, and at the moment, the mechanisms of eliminating the tail vortex of the propeller, recovering energy loss and increasing thrust basically disappear; on the contrary, the vortex behind the propeller is more disordered, so that the resistance is greatly increased, under the condition, the ship needing beaching in the inland river cannot be compensated, and an energy-saving rudder ball and a rudder-attached thrust fin are formed on the inland river, mainly on the ship with a plurality of torrential beaches, which can not be widely popularized.

The flap rudder is a common rudder with the highest efficiency at present, the flap rudder is a rudder with a rotatable tail wing, and a rudder blade is divided into a main body and the tail wing and connected by a hinge shaft. When the rudder blade is at a zero rudder angle, the main body of the rudder blade and the empennage are in the same plane, the whole rudder blade is in a symmetrical wing shape, when the rudder blade rotates from 0 position, the empennage rotates along with the main body and simultaneously rotates around the hinge shaft, so that the included angle between the empennage and the main rudder is increased, and the whole rudder becomes similar to a variable camber wing. The rudder angle of the flap rudder changes with the rudder angle to form a curved surface with variable camber, when the rudder is in a full rudder position, the turning angle of the main rudder blade is 35 degrees, the turning angle of the tail wing can reach 70 degrees, at the moment, the wake flow of the propeller passes through the main rudder blade and the tail wing and is folded twice, so that the large thrust of the propeller is converted into the transverse ship turning capability, and the rudder effect of the flap rudder is improved.

Therefore, when the flap rudder is at the 0 position, the flap rudder is equivalent to a common symmetrical plane wing-shaped rudder, good course stability can be kept, when the rudder leaves the 0 position, the flap rudder becomes a curved surface with variable camber, and the turning performance of the ship is changed to a great extent, so that a large number of real ship uses and researches indicate that the flap rudder is the rudder with the highest efficiency at the present stage.

However, the flap rudder has a complex structure, high manufacturing cost and high maintenance cost, particularly has larger indirect loss in the case of sea damage, and forms a pain point which is difficult to select for shipping enterprises due to unacceptable inspection of high cost and maintenance cost although the flap rudder has high rudder efficiency.

The high-performance combined rudder provided by the invention has the advantages of high efficiency of a flap rudder, and a structure equivalent to that of a common rudder, so that the high-performance combined rudder has great significance in low manufacturing cost, convenience in maintenance and use and low maintenance cost.

When the wing rudder is at a rudder angle of 0, a relatively complete airfoil profile can be maintained, however, the lift force of the wing rudder is very large, the airfoil profile must be designed to have a large thickness ratio to ensure the bending strength of the rudder design, and the larger the thickness ratio of the rudder is, the larger the resistance is, which is unfavorable for the propulsion efficiency.

Therefore, the invention of the combined rudder with the flap rudder efficiency and the conventional watershed linear rudder section is also a subject of important research in the ship industry.

Research and experiments of the prior art of matching the paddle rudder with an energy-saving technology show that the gap between the front end of the rudder ball and the hub cap of the propeller is as small as possible without influencing the arrangement of the rudder, but the rudder ball is close to the rear of the propeller and can hinder the disassembly of the propeller, which is also a negative factor of the technology. Therefore, a solution for balancing the contradiction between the small gap between the rudder ball mounting position and the propeller hub cap and the convenient propeller disassembly is an alternative way for the excavation with fine energy-saving technology.

At the present stage, due to the arrangement requirement of a conventional ship rudder device, the distance between a rudder blade and an outer plate of a ship body and the consideration that the rudder does not generate friction with the outer plate of the ship body, a section of clearance between the rudder blade and the ship body forms a rudder stock which is exposed, when the ship sails forwards or backwards, the exposed blunt shape meets incoming flow to form resistance, and the rapidity is not favorable.

Between the diversion drag reduction fin and the rudder blade, because the drag reduction fin is fixed on the ship body, the rudder blade has a corner which is more than 0 to +/-35 degrees when the rudder blade rotates, a gap must be reserved between the diversion drag reduction fin and the rudder blade, when the gap is too large, a vortex can be generated when incoming flow passes through the gap, adverse effect is generated on the rapidity, the gap between the diversion drag reduction fin and the rudder blade is reduced to the minimum, and the opportunity of generating the vortex disappears.

Disclosure of Invention

The invention aims to overcome the defects of the prior art and provide a high-performance combined rudder which integrates an energy-saving rudder ball, a rudder attached with a thrust fin, a reduced integral rudder resistance and a simplified structure of a wing rudder, can stabilize the high-efficiency technology of the energy-saving attached body and the wing rudder, and is generated on a sailing ship for a long time, the combination of a static rudder and a dynamic rudder forms a combined rudder with a large flap, and the rudder of the large flap reduces the steering frequency to a great extent, thereby reducing the sailing resistance of the ship, improving the steering efficiency and generating the energy-saving effect at the same time.

In order to achieve the technical features, the invention is realized as follows: a high performance combination rudder comprising a rudder unit assembly, said rudder unit assembly comprising a first rudder unit and a second rudder unit;

the first rudder device comprises a first rudder blade, the first rudder blade is arranged at the bottom end of a first rudder stock assembly, the first rudder stock assembly is rotatably arranged in a ship body rudder device platform, and the first rudder stock assembly is connected with a steering engine for providing steering power through a first rudder handle;

the second rudder device comprises a second rudder blade, the second rudder blade is installed at the bottom end of a second rudder stock assembly, the second rudder stock assembly is installed inside the ship body rudder device platform and is arranged in parallel with the central line of the first rudder stock assembly, the top end of the second rudder stock assembly is fixedly installed on a rudder stock fixing structure in a limiting mode through a second rudder stock, and the rudder stock fixing structure is fixed on a ship body structure;

the second rudder blade does not rotate, the first rudder blade can rotate around the first rudder stock assembly, and the front edge of the first rudder blade and the rear edge of the second rudder blade are of convex-concave semi-arc rotation fit structures.

Energy-saving rudder balls are arranged on the second rudder blade and at positions coinciding with the axial lead of the propeller, and rudder attached thrust fins are symmetrically fixed on two outer sides of each energy-saving rudder ball;

the flow guiding and drag reducing fins are arranged right above the first rudder blade and the second rudder blade at a certain interval.

The first rudder stock assembly comprises a first rudder stock, and the first rudder stock is rotatably supported on the ship rudder device platform through a first lower rudder carrier body, a first lower anti-wear bushing, a first rudder sleeve and a first upper rudder carrier body;

a first bushing is arranged between the first upper rudder carrier body and the first rudder stock, a first self-aligning roller bearing is arranged in the first bushing, and the top end of the first self-aligning roller bearing supports the first rudder stock through a first rudder stock clamping ring and a first check ring; the top end of the first upper rudder bearing body is provided with a paper pad and a first end cover in a pressing mode through a first bolt, a spring washer and a nut; a first felt oil seal is arranged between the first end cover and the first rudder stock;

the first tiller is fixed at the top end of the first tiller through a first flat key, a first brake block, a first tiller nut and a first lifting ring;

a first J-shaped frameless rubber oil seal, a first oil seal pressing plate, a first water seal and a first water seal pressing plate are arranged between the bottom end of the first lower rudder carrier body and the first rudder stock and are fixed through a second bolt, a spring washer and a nut in a press fit mode;

the first rudder sleeve and the first upper rudder bearing body are respectively communicated and provided with a pressure oil injection cup; an air pipe is communicated and installed on the first upper rudder carrier body.

The second rudder stock assembly comprises a second rudder stock, and the second rudder stock is rotatably supported on the ship rudder device platform through a second lower rudder bearing body, a second lower wear-resistant bushing, a second rudder sleeve and a second upper rudder bearing body;

a second self-aligning roller bearing is arranged between the second upper rudder carrier body and the second rudder stock, and the top end of the second self-aligning roller bearing supports the second rudder stock through a second rudder stock clamping ring and a second retaining ring; the top end of the second upper rudder bearing body is provided with a paper pad and a second end cover in a pressing mode through a third bolt, a spring washer and a nut; a second felt oil seal is arranged between the second end cover and the second rudder stock;

the second tiller is fixed at the top end of the second tiller through a second flat key, a second brake block, a second tiller nut and a second lifting ring; the other end of the second tiller is fixedly connected with the tiller fixing structure;

a second J-shaped frameless rubber oil seal, a second oil seal pressing plate, a second water seal and a second water seal pressing plate are arranged between the bottom end of the second lower rudder carrier body and the second rudder stock and are fixed through a fourth bolt, a spring washer and a nut in a press fit mode;

the second rudder sleeve and the second upper rudder bearing body are respectively communicated and provided with a pressure oil injection cup; an air pipe is communicated and installed on the second upper rudder bearing body.

A first rudder stock hole matched with the first rudder stock is formed in the first rudder stock, a first rotating arm is arranged on the side wall of the first rudder stock in parallel, and a first rotating arm hole is formed in the other end of the first rotating arm.

And a second rudder stock hole matched with the second rudder stock is processed on the second rudder stock, a second rotating arm is arranged on the side wall of the second rudder stock, and a second rotating arm hole is processed at the other end of the second rotating arm.

The rudder stock fixing structure comprises a first vertical plate fixed on the top of the ship body rudder device platform in parallel, reinforcing rib plates arranged in parallel are arranged between the outer wall of the first vertical plate and the ship body rudder device platform, a top plate is fixed on the top of the first vertical plate and the top of the reinforcing rib plates, a through hole is processed in the center of the top plate, and the through hole penetrates through a bolt and is matched and connected with a second rotating arm hole of the second rudder stock.

The first rudder blade comprises a horizontal rib plate and a vertical truss which are arranged inside the rudder blade, a first streamline outer plate is arranged outside the horizontal rib plate and the vertical truss, the top of the first rudder blade is sealed by an upper flow control plate, and the bottom of the first rudder blade is sealed by a lower flow control plate; and the upper flow control plate and the lower flow control plate are provided with water discharging cocks, and one end of the first rudder blade, which is matched with the second rudder blade, is sealed by a first semicircular pipe.

The second rudder blade comprises a rudder blade truss arranged in the second rudder blade, a first streamline-type outer plate is arranged outside the rudder blade truss, the top of the second rudder blade is sealed by an upper sealing plate, and the bottom of the second rudder blade is sealed by a lower sealing plate; the upper sealing plate and the lower sealing plate are provided with water discharging cocks, the front edge of the second rudder blade is provided with a seamless steel pipe, and one end of the second rudder blade, which is matched with the first rudder blade, is sealed by a second semicircular pipe; and a mounting gap is formed between the second semicircular pipe and the first semicircular pipe of the first rudder blade.

According to the characteristic of no rotation of a second rudder device, an energy-saving rudder ball and rudder attached thrust fins are arranged on the central line of propeller shaft systems on two sides of the rudder, the front edge of a first rudder blade and the rear edge of a second rudder blade are in convex-concave semi-arc shapes, and the shape of the first rudder blade is designed as follows:

determining the height of a rudder according to the shape and the size of the tail part of a ship body of a designed ship, determining the maximum outer diameter of a first lower rudder bearing body as the section thickness of the rudder, determining the radius of the front edge of a first rudder blade by taking the center line of a first rudder stock as the center of a circle and the radius of 1/2 of the maximum thickness as half, determining the distance between the front edge of the first rudder blade and the center of the first rudder stock, selecting the minimum distance between the center of the first rudder stock and the rear of a propeller to determine the width of a second rudder blade, determining the total width of the first rudder blade and the second rudder blade as the total width of the combined rudder, combining the first rudder blade and the second rudder blade into a whole according to the section value of the streamline shape of the rudder blade, leaving a proper gap to obtain the width of the second rudder blade after the shape and the size of the front edge of the first rudder blade are known, designing the tail edge of the second rudder blade into a concave arc shape, and taking the front section according to the total width of the first rudder blade and the second rudder blade to obtain a section, after the shapes of the two rudders are obtained, the rudder blade is designed according to a streamline rudder blade structure;

after the first rudder blade and the second rudder blade are designed according to the integral section, when the first rudder blade is at the 0 position, the second rudder blade is stably positioned in the axial forward and backward direction of the propeller for a long time, when the first rudder blade is rotated, the state that the flap is rotated along with the main rudder like a flap rudder is realized, the camber is increased along with the rotating angle of the first rudder blade, the propeller wake flow is recovered by an energy-saving rudder ball and a rudder auxiliary thrust fin on the second rudder blade and then flows through the first rudder blade, at the moment, the propeller wake flow forms a turning direction due to the rotating angle of the first rudder blade, and most of the propeller wake flow is converted into a ship-rotating moment.

The invention has the following beneficial effects:

1. the invention provides a high-performance combined rudder which integrates an energy-saving rudder ball, a rudder thrust, an integral rudder resistance reduction function and a simplified wing rudder structure, the combined rudder can stably and long-term generate the high-efficiency technology of the energy-saving attached body and the wing rudder on a sailing ship, the combination of a static rudder and a dynamic rudder of a second rudder blade and a first rudder blade forms a combined rudder of a large flap, and the rudder of the large flap greatly reduces the steering frequency, thereby reducing the sailing resistance of the ship, improving the steering effect and generating the energy-saving effect.

2. The combined rudder disclosed by the invention specifically relates to a process that firstly a common rudder design method is adopted to determine the height of the rudder, then the overall width of a second rudder blade and a first rudder blade is determined, the two rudders are combined into one according to the blade section type value of the common streamline rudder to carry out section design, after the shapes of the two rudders are obtained, the combined rudder is designed according to the structure of the conventional streamline rudder blade, and the combined rudder has no particularly complex structure, is simple to manufacture and is convenient to install.

3. Compared with the prior flapped rudder which adopts a hinged shaft to connect the flap with the main rudder, the invention has the difference that the first rudder blade is equivalent to the conventional rudder, the structure is simple, the construction is convenient, when the steering engine starts to rotate the first rudder blade, because the second rudder blade exists in front of the first rudder blade for a long time, the first rudder blade and the second rudder blade form the special relation of the main rudder and the flap by a simple combination method, and the design of the first rudder blade is enough according to about 70 percent of the area coefficient of the conventional flapped rudder, actually, the area of the first rudder blade is enough, and the flap effect of the conventional flapped rudder is larger.

4. The second rudder blade is stably positioned in the forward and backward direction of the propeller for a long time, and is fixed on the ship body structure by the rudder handle and the pin shaft, and the rudder area is equivalent to the balance area of the common rudder, and the rudder area of the second rudder blade is only about 1/3 of the common rudder, so that the rudder is light in weight and more convenient to disassemble and assemble; according to the scheme, when the vortex generated by the propeller flows through the second rudder blade, the second rudder blade and the energy-saving rudder ball and the rudder are used for adding thrust, so that the energy of the vortex of the propeller hub can be recovered more efficiently, and a considerable energy-saving effect is achieved.

5. According to the invention, the convex front edge of the first rudder blade is matched with the concave rear edge of the second rudder blade, and the convex front edge of the first rudder blade and the concave rear edge of the second rudder blade are only in clearance fit, so that the whole linear fairing is realized, the propeller wake flow can smoothly flow through the surfaces of the combined rudders of the first rudder blade and the second rudder blade, and the improvement of the propulsion efficiency is facilitated.

6. Several innovative features of the second rudder blade in the present invention are: firstly, because the second rudder blade is in a long-term static state and is kept on the same axis with the propeller wake, the energy-saving rudder bulb and the rudder attached thrust fin are also stably positioned behind the propeller for a long time, the efficiency of clearing the propeller wake vortex and recovering the propeller wake hub vortex energy can not be reduced all the time when the ship sails, the efficiency can reach 100%, and compared with the situation that the energy-saving efficiency is reduced or negative effects are generated when the rudder attached thrust fin rotates the rudder no matter in various types at present, the actual energy-saving effect is improved revolutionarily.

Drawings

The invention is further illustrated by the following figures and examples.

Fig. 1 is a general view of a rudder apparatus according to the present invention.

FIG. 2 is a cross-sectional view A-A of FIG. 1 according to the present invention.

FIG. 3 is a cross-sectional view B-B of FIG. 1 according to the present invention.

FIG. 4 is a cross-sectional view of C-1, C-2, C-3, C-4 and C-5 of FIG. 1 according to the present invention.

FIG. 5 is a graph of the half width of the drag fin of C-5 of FIG. 4 according to the present invention.

FIG. 6 is a D-D view of the second tiller of FIG. 3 in accordance with the present invention.

FIG. 7 is a view from E of FIG. 6 according to the present invention.

Fig. 8 is a cross-sectional view of a first tiller of the present invention.

FIG. 9 is a top view of the first tiller according to the present invention.

FIG. 10 is a sectional view showing a tiller fixing structure according to the present invention.

Fig. 11 is a view from direction F of fig. 10 in accordance with the present invention.

Fig. 12 is a view from direction G of fig. 10 in accordance with the present invention.

Fig. 13 is a schematic rudder view of the present invention.

Fig. 14 is a view showing a structure of a first rudder blade according to the present invention.

FIG. 15 is a cross-sectional view of H-1, H-2, H-3 and H-4 of FIG. 14 in accordance with the present invention.

FIG. 16 is a cross-sectional view of K-1, K-2, K-3, K-4, K-5 and K-6 of FIG. 14 according to the present invention.

Fig. 17 is a structure diagram of the energy-saving rudder ball and the second rudder blade.

FIG. 18 is a view M-M of FIG. 17 according to the present invention.

FIG. 19 is a view from N-N of FIG. 17 according to the present invention.

Fig. 20 is a structure diagram of the energy-saving rudder ball of the invention.

In the figure: the rudder blade comprises a first rudder blade 1, a first rudder stock 2, a first lower rudder carrier body 3, a first lower anti-abrasion bushing 4, a first oil seal pressing plate 5, a first water seal pressing plate 6, a first water seal 7, a first J-shaped frameless rubber oil seal 8, a paper pad 9, a spring washer 10, a second bolt 11, a nut 12, a first rudder sleeve 13, a pressure filling oil cup 14, an air pipe 15, a first upper rudder carrier body 16, a first bushing 17, a first self-aligning roller bearing 18, a first rudder stock snap ring 19, a first check ring 20, a first bolt 21, a first felt oil seal 22, a first end cover 23, a first upper rudder carrier body 24, a first flat key 25, a first brake block 26, a first rudder stock nut 27, a first lifting ring 28, a second rudder stock 29, a second rudder blade 30, a fourth bolt 31, a second pressing plate 32, a second water seal 33, a second pressing plate 34, a second J-shaped frameless rubber anti-abrasion bushing 35, and a second lower anti-abrasion bushing 36, The second lower rudder carrier body 37, the second rudder sleeve 38, the second upper rudder carrier body 39, the second self-aligning roller bearing 40, the second rudder stock snap ring 41, the second retainer ring 42, the second end cover 43, the second felt oil seal 44, the second rudder stock 45, the second flat key 46, the second brake block 47, the second rudder stock nut 48, the second suspension ring 49, the rudder stock fixing structure 50, the flow-guiding drag-reducing fin 51, the energy-saving rudder ball 52, the rudder-attached thrust fin 53 and the ship body rudder device platform 54;

a first streamline outer plate 101, a water discharging cock 102, an upper flow control plate 103, a lower flow control plate 104, a horizontal rib plate 105, a vertical truss 106 and a first semi-circular pipe 107;

an upper sealing plate 3001, a seamless steel pipe 3002, a lower sealing plate 3003, a rudder blade truss 3004, a first streamline outer plate 3005, a second semicircular pipe 3006 and an installation gap 3007;

a first swivel arm hole 2401, a first swivel arm 2402, a first rudder stock hole 2403, a second rudder stock hole 4501, a second swivel arm 4502, and a second swivel arm hole 4503;

stiffened plate 5001, first riser 5002, roof 5003, through-hole 5004.

Detailed Description

Embodiments of the present invention will be further described with reference to the accompanying drawings.

Example 1:

referring to fig. 1-20, a high performance combination rudder includes a rudder unit assembly including a first rudder unit and a second rudder unit; the first rudder device comprises a first rudder blade 1, the first rudder blade 1 is installed at the bottom end of a first rudder stock assembly, the first rudder stock assembly is rotatably installed inside a ship body rudder device platform 54, and the first rudder stock assembly is connected with a steering engine for providing rudder turning power through a first rudder handle 24; the second rudder device comprises a second rudder blade 30, the second rudder blade 30 is installed at the bottom end of a second rudder stock assembly, the second rudder stock assembly is installed inside a ship body rudder device platform 54 and is arranged in parallel with the central line of the first rudder stock assembly, the top end of the second rudder stock assembly is fixedly installed on a rudder stock fixing structure 50 in a limiting mode through a second rudder stock 45, and the rudder stock fixing structure 50 is fixed on a ship body structure; the second rudder blade 30 does not rotate, the first rudder blade 1 can rotate around the first rudder stock assembly, and the front edge of the first rudder blade 1 and the rear edge of the second rudder blade 30 adopt a convex-concave semi-arc type rotation matching structure. The invention provides a high-performance combined rudder which integrates an energy-saving rudder ball, a rudder thrust, an integral rudder resistance reduction function and a simplified wing-shaped rudder structure, the combined rudder can stably and long-term generate the high-efficiency technology of the energy-saving attached body and the wing-shaped rudder on a sailing ship, the combination of a static rudder and a dynamic rudder formed by combining a second rudder blade 30 and a first rudder blade 1 forms a combined rudder of a large flap, and the rudder of the large flap greatly reduces the steering frequency, thereby reducing the sailing resistance of the ship, improving the steering efficiency and simultaneously generating the energy-saving effect.

Further, an energy-saving rudder ball 52 is arranged on the second rudder blade 30 and at a position coinciding with the propeller axis, and rudder auxiliary thrust fins 53 are symmetrically fixed on two outer sides of the energy-saving rudder ball 52; the flow guiding and resistance reducing fins 51 are arranged right above the first rudder blade 1 and the second rudder blade 30 at a certain interval. The energy-saving effect is further achieved by adding the energy-saving rudder ball 52 and the rudder additional thrust fin 53.

Further, the first rudder stock assembly comprises a first rudder stock 2, and the first rudder stock 2 is rotatably supported on the ship rudder device platform 54 through a first lower rudder carrier body 3, a first lower anti-wear bushing 4, a first rudder sleeve 13 and a first upper rudder carrier body 16; a first bushing 17 is arranged between the first upper rudder carrier body 16 and the first rudder stock 2, a first self-aligning roller bearing 18 is installed in the first bushing 17, and the top end of the first self-aligning roller bearing 18 supports the first rudder stock 2 through a first rudder stock snap ring 19 and a first check ring 20; the top end of the first upper rudder carrier body 16 is provided with a paper pad 9 and a first end cover 23 through a first bolt 21, a spring washer 10 and a nut 12 in a pressing way; a first felt oil seal 22 is arranged between the first end cover 23 and the first rudder stock 2; the first tiller 24 is fixed at the top end of the first tiller 2 through a first flat key 25, a first brake block 26, a first tiller nut 27 and a first lifting ring 28; a first J-shaped frameless rubber oil seal 8, a first oil seal pressing plate 5, a first water seal 7 and a first water seal pressing plate 6 are arranged between the bottom end of the first lower rudder carrier body 3 and the first rudder stock 2 and are fixed through a second bolt 11, a spring washer 10 and a nut 12 in a press-fitting manner; the first rudder sleeve 13 and the first upper rudder bearing body 16 are respectively communicated and provided with a pressure oil injection cup 14; an air pipe 15 is installed on the first upper rudder carrier body 16 in a communicating manner. Can guarantee through foretell rudder stock assembly that first rudder blade can rotate under the steering wheel effect.

Further, the second rudder stock assembly comprises a second rudder stock 29, and the second rudder stock 29 is rotatably supported on the ship rudder device platform 54 through a second lower rudder carrier body 37, a second lower wear-resistant bushing 36, a second rudder sleeve 38 and a second upper rudder carrier body 39; a second self-aligning roller bearing 40 is arranged between the second upper rudder carrier body 39 and the second rudder stock 29, and the top end of the second self-aligning roller bearing 40 supports the second rudder stock 29 through a second rudder stock snap ring 41 and a second check ring 42; the top end of the second upper rudder carrier body 39 is pressed with a paper pad 9 and a second end cap 43 through a third bolt, a spring washer and a nut; a second felt oil seal 44 is arranged between the second end cover 43 and the second rudder stock 29; the second tiller 45 is fixed at the top end of the second tiller 29 through a second flat key 46, a second brake block 47, a second tiller nut 48 and a second lifting ring 49; the other end of the second tiller 45 is fixedly connected with the tiller fixing structure 50; a second J-shaped frameless rubber oil seal 35, a second oil seal pressing plate 34, a second water seal 33 and a second water seal pressing plate 32 are arranged between the bottom end of the second lower rudder carrier body 37 and the second rudder stock 29 and are fixed through a fourth bolt 31, a spring washer 10 and a nut 12 in a press-fitting manner; the second rudder sleeve 38 and the second upper rudder bearing body 39 are respectively communicated and provided with a pressure oil injection cup 14; the second upper rudder carrier body 39 is provided with an air pipe 15 in a communicating manner. Through foretell second rudderstock assembly, can be used for carrying out fixed mounting to the second rudder blade to make things convenient for it to hang and dismantle.

Further, a first rudder stock hole 2403 used for being matched with the first rudder stock 2 is processed on the first rudder stock 24, a first rotating arm 2402 is arranged on the side wall of the first rudder stock 24 in parallel, and a first rotating arm hole 2401 is processed at the other end of the first rotating arm 2402. Through foretell first tiller 24, guaranteed that the steering wheel can drive its first rudderstock and rotate, and then realized the rotation of first rudder blade.

Further, a second rudder stock hole 4501 for engaging with the second rudder stock 29 is formed in the second rudder stock 45, a second rotating arm 4502 is disposed on a side wall of the second rudder stock 45, and a second rotating arm hole 4503 is formed at the other end of the second rotating arm 4502. The second tiller 45 can be used to fix the first tiller and prevent it from rotating.

Further, the tiller fixing structure 50 includes a first vertical plate 5002 fixed in parallel on the top of the hull rudder device platform 54, a reinforcing rib plate 5001 arranged in parallel is arranged between the outer wall of the first vertical plate 5002 and the hull rudder device platform 54, a top plate 5003 is fixed on the tops of the first vertical plate 5002 and the reinforcing rib plate 5001, a through hole 5004 is processed in the center of the top plate 5003, and the through hole 5004 passes through a bolt and is connected with a second rotating arm hole 4503 of the second tiller 45 in a matching manner. The tiller fixing structure 50 described above can be used to fix the second tiller 45.

Further, the first rudder blade 1 comprises a horizontal rib plate 105 and a vertical truss 106 which are arranged inside the rudder blade, a first streamline-shaped outer plate 101 is arranged outside the horizontal rib plate 105 and the vertical truss 106, the top of the first rudder blade 1 is sealed by an upper flow control plate 103, and the bottom of the first rudder blade 1 is sealed by a lower flow control plate 104; the upper flow control plate 103 and the lower flow control plate 104 are provided with a water discharging cock 102, and one end of the first rudder blade 1, which is matched with the second rudder blade 30, is closed by a first semicircular pipe 107. The first rudder blade 1 can be rotated by the first rudder stock.

Further, the second rudder blade 30 includes a rudder blade truss 3004 arranged inside the second rudder blade 30, a first streamlined outer plate 3005 is arranged outside the rudder blade truss 3004, the top of the second rudder blade 30 is closed by an upper closing plate 3001, and the bottom of the second rudder blade 30 is closed by a lower closing plate 3003; a water discharging cock is arranged on the upper sealing plate 3001 and the lower sealing plate 3003, a seamless steel pipe 3002 is arranged at the front edge of the second rudder blade 30, and one end of the second rudder blade 30, which is matched with the first rudder blade 1, is sealed by a second semicircular pipe 3006; an installation gap 3007 is provided between the second semicircular tube 3006 and the first semicircular tube 107 of the first rudder blade 1. Is held stationary by the second rudder blade 30 as described above.

Example 2:

according to the characteristic of non-rotation of a second rudder device, an energy-saving rudder ball 52 and rudder attached thrust fins 53 are arranged on the central line of a propeller shaft system on two sides of the energy-saving rudder ball 52, the front edge of a first rudder blade 1 and the rear edge of a second rudder blade 30 are in convex-concave semi-arc shapes, and the shape of the first rudder blade 1 is designed as follows:

determining the height of a rudder according to the tail molded line of a ship body of a designed ship, determining the thickness of a rudder section by taking the maximum outer diameter of a first lower rudder bearing body 3, determining the radius of the front edge of a first rudder blade 1 by taking the center line of a first rudder stock 2 as the center of a circle and 1/2 as half of the maximum thickness, determining the distance between the front edge of the first rudder blade 1 and the center of the first rudder stock 2, selecting the minimum distance between the center of the first rudder stock 2 and a propeller to determine the width of a second rudder blade 30, determining the total width of the first rudder blade 1 and the second rudder blade 30 as the total width of the combined rudder, combining the first rudder blade 1 and the second rudder blade 30 into a whole according to the blade section molded value of a streamline rudder, obtaining the width of the second rudder blade 30 by leaving a proper gap after the shape and the scale of the front edge of the first rudder blade 1 are known, designing the tail edge of the second rudder blade 30 into a concave arc shape, and taking the section of the second rudder blade 30 according to the total width of the first rudder blade 1 and the second rudder blade 30, after the shapes of the two rudders are obtained, the two rudders are designed according to a streamline rudder blade structure; there is no particularly complicated structure. Simple manufacture and convenient installation.

After the first rudder blade 1 and the second rudder blade 30 are designed according to the integral section, when the first rudder blade 1 is at 0 position, due to the existence of the second rudder blade 30, the first rudder blade 1 is stably positioned in the axial forward and backward direction of the propeller for a long time, when the first rudder blade 1 is rotated, the state that the flap is rotated along with the main rudder like a flap wing rudder is realized, the camber is increased along with the rotating angle of the first rudder blade 1, the propeller wake flow is recovered by the energy-saving rudder ball 52 on the second rudder blade 30 and the rudder attached thrust fin 53 through the second rudder blade 30 and then flows through the first rudder blade 1, at the moment, the propeller wake flow forms a turning direction due to the rotating angle of the first rudder blade 1, and the great part of the propeller wake flow is converted into a ship-rotating moment.

The principle of the invention is as follows:

through the structure of the invention, the contradiction that the energy-saving rudder ball and rudder attached thrust fin can reduce the energy-saving effect when the rudder needs to be turned is balanced, gap assembly is adopted, and compared with the existing flap rudder which adopts a hinged shaft to connect a flap with a main rudder, the invention has the difference that the first rudder blade 1 is equivalent to the conventional rudder, the structure is simple, the construction is convenient, when the steering engine starts to rotate the first rudder blade 1, because the second rudder blade 30 is fixed in front of the first rudder blade 1 for a long time, the first rudder blade 1 and the second rudder blade 30 form a special relationship between the main rudder and the flap by using a simple combination method, and the design of the first rudder blade 1 is enough according to about 70 percent of the area coefficient obtained by the conventional flap rudder, actually, the area of the first rudder blade 1 is enough, and the flap effect is larger than that of the conventional flap.

The second rudder blade 30 is stable in the forward-rearward direction of the propeller for a long period of time. The rudder handle and the pin shaft are fixed on the ship body structure, the rudder area is equivalent to the balance area of the common rudder, and the rudder area of the second rudder blade 30 is only about 1/3 of the common rudder, so that the weight is light, and the rudder is more convenient to disassemble and assemble; according to the scheme, when the vortex generated by the propeller flows through the second rudder blade 30, the energy of the vortex of the propeller hub can be efficiently recovered together with the energy-saving rudder ball and the rudder attached thrust fin, and a considerable energy-saving effect is achieved.

Because the convex front edge of the first rudder blade 1 is matched with the concave rear edge of the second rudder blade 30, the first rudder blade 1 and the second rudder blade 30 are only in clearance fit, the whole linear is smooth, and the propeller wake flow can smoothly flow through the surfaces of the combined rudders of the first rudder blade 1 and the second rudder blade 30, so that the propeller propulsion efficiency is improved.

The second rudder blade 30 of the invention is carried out by adopting the structure and the manufacturing method of the conventional rudder blade and device, the structure is simple, the manufacture and the installation are convenient, simultaneously, the energy-saving rudder ball and the rudder are manufactured together with the thrust storage, and the second rudder blade 30 is very simply hoisted to the ship according to the installation method of the common rudder, the invention is characterized in that the part 'the rudder stock' in the rudder device adopts a fixed pin shaft to integrally connect and fix the second rudder blade 30 on the ship structure, the fixation is realized by welding a positioning pin base, the second rudder blade 30 is fixed on the rudder stock and integrally connected and fixed on the ship structure by the fixed pin shaft, and the second rudder blade 30 is fixed on the ship body and is in the state on the same axis with the propeller for a long time, thus, the invention embodies several innovative characteristics of the fixed state of the second rudder blade 30: firstly, because the second rudder blade 30 is in a long-term static state and is kept on the same axis with the propeller wake, the rudder bulb and the rudder attached thrust fin are also stably positioned behind the propeller for a long time, when the ship sails, the efficiency of clearing the propeller wake vortex and recovering the propeller wake hub vortex energy can not be reduced all the time, the efficiency can reach 100%, and compared with the situation that the energy-saving efficiency is reduced or the negative effect is played when the rudder attached thrust fin rotates the rudder no matter in various types of rudder bulbs, the actual energy-saving effect is revolutionarily improved.

Due to the existence of the second rudder blade 30, the second rudder blade is in a forward direction stably for a long time, when the first rudder blade 1 steers, the first rudder blade 1 realizes the state of a flap where a flap rudder rotates along with a main rudder, the camber is increased along with the rotation angle of the first rudder blade 1, the propeller wake flows through the first rudder blade 1 after being recovered by an energy-saving rudder bulb and a rudder attached thrust fin of the second rudder blade 30 and the second rudder blade 30, the propeller wake flows form a folding direction due to the rotation angle of the first rudder blade 1, and the large coming flow of the propeller is converted into a steering torque. The balance must be changed the rudder by the big angle and the energy-saving efficiency of rudder ball, rudder attached thrust fin is subdued contradiction. From the foregoing, the energy saving effects of the rudder ball and the rudder thrust fin during large-angle rudder turning can be reduced and even have negative effects.

In order to achieve the fine excavating energy-saving technology, the high-performance combined rudder is provided with the following scheme that the diversion drag reduction fin is matched with the combined rudder to realize the following functions: the outer circle diameter of the lower rudder bearing body is the thickness. The total width 1/2 of the combined rudder is taken as the length, the section of the flow-guiding drag-reducing fin is designed according to the section value of a common rudder blade, and the height is determined by taking the intersection line of the front edge of the flow-guiding drag-reducing fin and a ship body as the reference. After the shape is determined, determining an internal vertical toggle plate framework by taking the space between the solid rib plates at the bottom of the ship as a space, wherein the drag reduction fin is manufactured by adopting a field lofting method; firstly, the first rudder blade 1 and the second rudder blade 30 of the rudder device are integrally shipped, then the drag reduction fin framework is installed, the side plates and the bottom sealing plates are installed in sequence according to the construction sequence, the tightness test is carried out after the welding is finished, and the paint is finally finished with the ship body. When the ship sails, the wake flow behind the propeller can smoothly flow through the flow guide drag reduction fin, and a little contribution can be made to the fine digging and submerging of the energy-saving technology.

The direction between the diversion drag reduction fin and the rudder blade is required to be provided with a directional gap with the diversion drag reduction fin due to the rudder turning of the rudder blade, a gap is usually reserved for convenient disassembly and assembly according to the conventional method, the gap can also form a vortex on a tail system of a propeller to reduce the propulsion efficiency, and the method disclosed by the invention can reduce the gap to the minimum and achieve the better energy-saving effect and adopts the following method: and a bearing snap ring in the rudder device part is arranged above the upper end surface of the upper rudder bearing body. The rudder blade and the rudder stock can be realized by a small gap with the flow-guiding drag-reducing fin when being hoisted; the bearing snap ring is positioned above the upper end surface of the upper rudder bearing body, so that the fixing ring positioned at the excircle of the bearing snap ring can be conveniently assembled; thus, the outer circles and the upper end faces of the weighing ring and the fixing ring are provided with parts, namely end covers, and the parts are connected with the upper rudder bearing body through at least more than 6 studs, so that a small gap between the rudder and the flow guide drag reduction fin is realized.

In summary, the second rudder blade 30 of the rudder device is stably fixed on the hull for a long time, so that a gap is not required to be formed between the second rudder blade 30 of the rudder device and the flow guiding drag reduction fin basically, and the second rudder blade 30 of the rudder device is manufactured by the method in the design process. Therefore, gapless matching between the two can be achieved, an integral streamline flow guide body is formed by the flow guide drag reduction fin and the second rudder blade 30 of the rudder blade, a high-performance energy-saving device for reducing the wake vortex of the propeller is formed, the vortex-reducing energy-saving characteristic and the energy-saving rudder ball are excellent, the energy-saving rudder has the effect of long-term stability of the thrust fin by 100%, and the static and dynamic matching of the first rudder blade 1 of the rudder device and the second rudder blade 30 of the rudder device has the characteristic of better rudder effect than a high-efficiency flap rudder.

Claims

1. A high performance combination rudder, characterized in that: the rudder device assembly comprises a first rudder device and a second rudder device;

the first rudder device comprises a first rudder blade (1), the first rudder blade (1) is installed at the bottom end of a first rudder stock assembly, the first rudder stock assembly is rotatably installed inside a ship body rudder device platform (54), and the first rudder stock assembly is connected with a steering engine for providing steering power through a first rudder handle (24);

the second rudder device comprises a second rudder blade (30), the second rudder blade (30) is installed at the bottom end of a second rudder stock assembly, the second rudder stock assembly is installed inside a ship body rudder device platform (54) and is arranged in parallel with the central line of the first rudder stock assembly, the top end of the second rudder stock assembly is fixedly installed on a rudder stock fixing structure (50) in a limiting manner through a second rudder stock (45), and the rudder stock fixing structure (50) is fixed on a ship body structure;

the second rudder blade (30) does not rotate, the first rudder blade (1) can rotate around the first rudder stock assembly, and the front edge of the first rudder blade (1) and the rear edge of the second rudder blade (30) adopt a convex-concave semi-arc rotation matching structure.

2. A high performance combination rudder as claimed in claim 1, wherein: energy-saving rudder balls (52) are arranged on the second rudder blade (30) and are overlapped with the axial lead of the propeller, and rudder auxiliary thrust fins (53) are symmetrically fixed on two outer sides of each energy-saving rudder ball (52);

the flow guiding and resistance reducing fins (51) are arranged right above the first rudder blade (1) and the second rudder blade (30) at a certain interval.

3. A high performance combination rudder as claimed in claim 1, wherein: the first rudder stock assembly comprises a first rudder stock (2), and the first rudder stock (2) is rotatably supported on a ship rudder device platform (54) through a first lower rudder carrier body (3), a first lower anti-wear bushing (4), a first rudder sleeve (13) and a first upper rudder carrier body (16);

a first bushing (17) is arranged between the first upper rudder carrier body (16) and the first rudder stock (2), a first self-aligning roller bearing (18) is installed inside the first bushing (17), and the top end of the first self-aligning roller bearing (18) supports the first rudder stock (2) through a first rudder stock snap ring (19) and a first check ring (20); the top end of the first upper rudder bearing body (16) is provided with a paper pad (9) and a first end cover (23) in a pressing mode through a first bolt (21), a spring washer (10) and a nut (12); a first felt oil seal (22) is arranged between the first end cover (23) and the first rudder stock (2);

the first tiller (24) is fixed to the top end of the first tiller (2) through a first flat key (25), a first brake block (26), a first tiller nut (27) and a first lifting ring (28);

a first J-shaped frameless rubber oil seal (8), a first oil seal pressing plate (5), a first water seal (7) and a first water seal pressing plate (6) are arranged between the bottom end of the first lower rudder carrier body (3) and the first rudder stock (2), and are fixed through a second bolt (11), a spring washer (10) and a nut (12) in a press-fitting manner;

the first rudder sleeve (13) and the first upper rudder bearing body (16) are respectively communicated and provided with a pressure oil injection cup (14); an air pipe (15) is communicated and installed on the first upper rudder carrier body (16).

4. A high performance combination rudder as claimed in claim 1, wherein: the second rudder stock assembly comprises a second rudder stock (29), and the second rudder stock (29) is rotatably supported on the ship rudder device platform (54) through a second lower rudder bearing body (37), a second lower anti-wear bushing (36), a second rudder sleeve (38) and a second upper rudder bearing body (39);

a second self-aligning roller bearing (40) is arranged between the second upper rudder carrier body (39) and the second rudder stock (29), and the top end of the second self-aligning roller bearing (40) supports the second rudder stock (29) through a second rudder stock clamping ring (41) and a second retaining ring (42); the top end of the second upper rudder bearing body (39) is provided with a paper pad (9) and a second end cover (43) in a pressing mode through a third bolt, a spring washer and a nut; a second felt oil seal (44) is arranged between the second end cover (43) and the second rudder stock (29);

the second tiller (45) is fixed at the top end of the second tiller (29) through a second flat key (46), a second brake block (47), a second tiller nut (48) and a second lifting ring (49); the other end of the second tiller (45) is fixedly connected with the tiller fixing structure (50);

a second J-shaped frameless rubber oil seal (35), a second oil seal pressing plate (34), a second water seal (33) and a second water seal pressing plate (32) are arranged between the bottom end of the second lower rudder carrier body (37) and the second rudder stock (29), and are fixed through a fourth bolt (31), a spring washer (10) and a nut (12) in a press-fitting manner;

the second rudder sleeve (38) and the second upper rudder bearing body (39) are respectively communicated and provided with a pressure oil injection cup (14); an air pipe (15) is communicated and installed on the second upper rudder carrier body (39).

5. A high performance combination rudder as claimed in claim 1 or 3, wherein: a first rudder stock hole (2403) used for being matched with the first rudder stock (2) is formed in the first rudder stock (24), a first rotating arm (2402) is arranged on the side wall of the first rudder stock (24) in parallel, and a first rotating arm hole (2401) is formed in the other end of the first rotating arm (2402).

6. A high performance combination rudder as claimed in claim 1 or 4, characterised in that: a second rudder stock hole (4501) used for being matched with a second rudder stock (29) is formed in the second rudder stock (45), a second rotating arm (4502) is arranged on the side wall of the second rudder stock (45), and a second rotating arm hole (4503) is formed in the other end of the second rotating arm (4502).

7. A high performance combination rudder as claimed in claim 1, wherein: the tiller fixing structure (50) comprises a first vertical plate (5002) fixed to the top of a ship body rudder device platform (54) in parallel, reinforcing rib plates (5001) arranged in parallel are arranged between the outer wall of the first vertical plate (5002) and the ship body rudder device platform (54), a top plate (5003) is fixed to the tops of the first vertical plate (5002) and the reinforcing rib plates (5001), a through hole (5004) is processed in the center of the top plate (5003), a bolt penetrates through the position of the through hole (5004), and the tiller fixing structure is connected with a second rotating arm hole (4503) of a second tiller (45) in a matched mode.

8. A high performance combination rudder as claimed in claim 1, wherein: the first rudder blade (1) comprises a horizontal rib plate (105) and a vertical truss (106) which are arranged inside the rudder blade, a first streamline-shaped outer plate (101) is arranged outside the horizontal rib plate (105) and the vertical truss (106), the top of the first rudder blade (1) is sealed by an upper flow control plate (103), and the bottom end of the first rudder blade is sealed by a lower flow control plate (104); a water discharging cock (102) is arranged on the upper flow control plate (103) and the lower flow control plate (104), and one end of the first rudder blade (1) matched with one end of the second rudder blade (30) is sealed by a first semicircular pipe (107).

9. A high performance combination rudder as claimed in claim 1, wherein: the second rudder blade (30) comprises a rudder blade truss (3004) arranged inside the second rudder blade, a first streamline-type outer plate (3005) is arranged outside the rudder blade truss (3004), the top of the second rudder blade (30) is sealed through an upper sealing plate (3001), and the bottom of the second rudder blade is sealed through a lower sealing plate (3003); a water discharging cock is arranged on the upper sealing plate (3001) and the lower sealing plate (3003), a seamless steel pipe (3002) is arranged at the front edge of the second rudder blade (30), and one end of the second rudder blade (30) matched with the first rudder blade (1) is sealed by a second semicircular pipe (3006); and an installation gap (3007) is arranged between the second semicircular pipe (3006) and the first semicircular pipe (107) of the first rudder blade (1).

10. A method for designing a high-performance combination rudder as claimed in any one of claims 1 to 9, wherein: according to the characteristic of non-rotation of the second rudder device, an energy-saving rudder ball (52) and a rudder attached thrust fin (53) are arranged on the central line of propeller shaft systems on two sides of the rudder attached thrust fin, the front edge of a first rudder blade (1) and the rear edge of a second rudder blade (30) are in convex-concave semi-arc shapes, and the shape of the first rudder blade (1) is designed as follows:

determining the height of a rudder according to the shape of the tail part of a ship body of a designed ship, determining the section thickness of the rudder by taking the maximum outer diameter of a first lower rudder bearing body (3) as the section thickness of the rudder, taking the center line of a first rudder stock (2) as the center of a circle, determining the radius of the front edge of a first rudder blade (1) by taking the maximum outer diameter of 1/2 as half, determining the distance between the front edge of the first rudder blade (1) and the center of the first rudder stock (2), selecting the minimum distance between the center of the first rudder stock (2) and a propeller to determine the width of a second rudder blade (30), determining the total width of the combined rudder by taking the total width of the first rudder blade (1) and the second rudder blade (30) as the total width of the combined rudder, combining the first rudder blade (1) and the second rudder blade (30) into a section design according to the section shape and the size of a streamline rudder, leaving a proper gap to obtain the width of the second rudder blade (30), and designing the tail edge of the second rudder blade (30) into a concave arc shape, taking the front section of the first rudder blade (1) and the second rudder blade (30) according to the total width integral value of the first rudder blade and the second rudder blade to form a section of the second rudder blade (30), and after the shapes of the two rudders are obtained, designing according to a streamline rudder blade structure;

after the first rudder blade (1) and the second rudder blade (30) are designed according to the integral section, when the first rudder blade (1) is at 0 position, due to the existence of the second rudder blade (30), the rudder blade is stably positioned at the axial forward and backward direction of the propeller for a long time, when the first rudder blade (1) is rotated, the state that a flap is positioned by the flap rudder along with the rotation of a main rudder is realized, the camber is increased along with the rotation angle of the first rudder blade (1), the propeller wake flow is recovered by an energy-saving rudder ball (52) and a rudder attached thrust fin (53) on the second rudder blade (30) through the second rudder blade (30) and then flows through the first rudder blade (1), at the moment, the propeller wake flow forms a turning direction due to the rotation angle of the first rudder blade (1), and the great part of the propeller wake flow is converted into a ship turning moment.