Stator type ship propulsion efficiency improving device and preparation method thereof

Abstract

The invention discloses a stator type ship propulsion efficiency improving device and a manufacturing method thereof. The manufacturing method comprises the steps that the length direction and the width direction which are perpendicular to each other are defined; at least three sections are sequentially arranged along the length direction, the front parts of the at least three sections are connected by a spline curve to form a guide edge, the rear parts of the at least three sections are connected by a straight line to form a following edge, and the at least three sections form a geometric surface along the guide edge and the following edge through a lofting curved surface; respectively rotating the at least three sections in required directions and required angles to form a stator; a plurality of stators are arranged in front of the propeller at intervals in the circumferential direction, and the circumferential direction is defined based on the rotation direction of the propeller. The stator can adapt to the incoming flow direction at different positions so as to deflect the incoming flow, so that the incoming flow entering the propeller is in the direction and angle which are more favorable for the blades, the incoming flow is more favorable for the blades of the propeller to generate lift force, and the stator can be better suitable for stern flow under the common influence of propeller rotation and hull geometry.

Description

Technical Field

[0001] The present invention relates to the technical field of ship propulsion, and particularly relates to a stator-type ship propulsion efficiency improvement device and a preparation method thereof. Background Art

[0002] By using the stator to deflect the oncoming flow direction and change the water flow velocity vector in front of the propeller, the efficiency of the propeller can be improved. Currently, existing hydrodynamic energy-saving devices in front of the propeller and ship propulsion efficiency improvement devices include various different forms. For existing propellers, the pitch and chord length are different from the blade root to the blade tip. Under the combined action of the propeller and the hull, the oncoming flow in front of the propeller is not parallel to the longitudinal direction of the hull, and the oncoming flow directions at different propeller radius positions are different. The relationship between the oncoming flow angle and the propeller radius is also non-linear. Therefore, the stator of the existing hydrodynamic energy-saving device in front of the propeller cannot be fully matched with the flow generated by the suction of the propeller, and this stator also cannot fully match the oncoming flow generated by the suction of the propeller because the relationship between the pitch and chord length distribution of the propeller and the propeller radius is not linear, resulting in the energy-saving effect of the existing stator not reaching the maximum.

[0003] Therefore, how to provide a stator-type ship propulsion efficiency improvement device and a preparation method thereof that can better improve the propulsion efficiency has become an urgent technical problem for those skilled in the art. Summary of the Invention

[0004] To achieve the above object, the present invention provides a stator-type ship propulsion efficiency improvement device and a preparation method thereof. The specific technical solutions are as follows:

[0005] A preparation method of a stator-type ship propulsion efficiency improvement device includes the following:

[0006] Define a length direction and a width direction that are perpendicular to each other. The opposite ends along the width direction are the front part and the rear part respectively;

[0007] Arrange at least three profiles in sequence along the length direction. The dimensions of the width direction of the at least three profiles are the same. Connect the front parts of the at least three profiles with a spline curve to form a leading edge, and connect the rear parts of the at least three profiles with a straight line to form a trailing edge. The at least three profiles are all perpendicular to the trailing edge. A geometric surface is formed by lofting the at least three profiles along the leading edge and the trailing edge;

[0008] Rotate the at least three profiles respectively in the required direction and at the required angle to form a stator. The required direction and the required angle are determined as follows: Obtain several oncoming flow directions corresponding to different profiles, and rotate the corresponding profiles in the required direction and at the required angle so that they all present a fixed preset angle with the several oncoming flows;

[0009] Arrange several of the above-mentioned stators in front of the propeller, where the front is the bow direction of the ship. The two ends of the stator along its length direction are respectively a fixed end and a distal end. Fix the fixed end to the hull in front of the propeller and keep the distal end away from the hull. Arrange the several stators at intervals in the circumferential direction, which is defined based on the rotation direction of the propeller.

[0010] Preferably, the ship is a bulk carrier, an oil tanker or a container ship, and the propellers of these ships are installed behind the stern shaft outlet of the hull.

[0011] Arrange four cross-sections in sequence along the length direction, namely cross-section one, cross-section two, cross-section three and cross-section four. Cross-section one is the fixed end and cross-section four is the distal end.

[0012] Cross-section one rotates 6 to 10 degrees counterclockwise around the trailing edge as the axis. Cross-section two rotates 1 to 2 degrees counterclockwise around the same axis. Cross-section three and cross-section four do not rotate or rotate 1 to 2 degrees clockwise around the same axis. Define clockwise and counterclockwise as follows: Make a fist with the right hand and extend the thumb. The thumb points from cross-section one to cross-section four along the trailing edge. At this time, the direction of rotation along the four fingers of the right hand around the thumb is the clockwise rotation, and the rotation direction opposite to the clockwise rotation is the counterclockwise rotation.

[0013] Preferably, define the length of the stator: The length of the stator is not greater than the radius of the circle swept by the tip of the propeller blade and not less than 0.9 times the radius of the circle swept by the tip of the propeller blade.

[0014] Define the distances between cross-section one to cross-section four as follows: Cross-section one and cross-section four are located at the two ends of the stator along its length direction. Cross-section two is located at the midpoint of the line connecting cross-section one and cross-section four in the length direction. Cross-section three is located at the midpoint of the line connecting cross-section two and cross-section four in the length direction.

[0015] Preferably, for a right-handed propeller, the several stators are arranged on the upper left side of the hull in front of the propeller. The directions are: with the left side of the hull as the left, the gravity direction as the bottom, and the direction opposite to the gravity direction as the top; or

[0016] For a left-handed propeller, the several stators are arranged on the upper right side of the hull in front of the propeller. The directions are: with the right side of the hull as the right, the gravity direction as the bottom, and the direction opposite to the gravity direction as the top.

[0017] Preferably, a duct is arranged at the distal end of each of the several stators, and the distal ends are fixedly connected to the inner surface of the duct.

[0018] Preferably, the number of the stators is 3 or 4.

[0019] Preferably, obtain the directions of the several oncoming flows through pool PIV tests or CFD.

[0020] Preferably, the geometric surface is smoothed by adjusting the curvature.

[0021] A stator-type ship propulsion efficiency improvement device is prepared by using the preparation method described in any one of the above.

[0022] The provided stator-type ship propulsion efficiency improvement device and its preparation method have the following technical effects:

[0023] In this preparation method, different torsion angles can be set at different positions of the stator, which can adapt to the oncoming flow direction at different positions, and then deflect the oncoming flow, so that the oncoming flow entering the propeller is in a more favorable direction and angle for the propeller blades, making the oncoming flow more conducive to the generation of lift by the propeller blades, and being better applicable to the stern flow under the combined influence of the propeller rotation and the hull geometry.

[0024] The oncoming flow velocity directions in front of the propeller at the sterns of bulk carriers, oil tankers and container ships have the following characteristics: The oncoming flow directions at the left side of the hull of a right-handed propeller ship at a distance of 1 times the propeller radius and at a distance of 0.5 times the propeller radius are relatively close. Usually, their projections on the mid-longitudinal plane of the ship differ by 2 to 4 degrees. The angle difference between the oncoming flow at a distance of 0.5 times the propeller radius and the oncoming flow close to the hull is relatively large. The projection of the oncoming flow direction close to the hull on the mid-longitudinal plane of the ship may differ from the projection of the oncoming flow direction at a distance of 0.5 times the propeller radius by 10 degrees.

[0025] Selecting four profiles for preparation can better adapt to the oncoming flow. In order to adapt to the oncoming flow direction, when the four profiles are rotated by different angles respectively, the fronts of the four profiles are connected by a spline curve to form a leading edge curve. At this time, the leading edge curve has 4 points for designers to adjust the curve curvature. Having too many points passed by the leading edge curve is not conducive to ensuring the smoothness of the leading edge curve; while when there are only three profiles, the number of points passed by the leading edge curve is too small, and it is difficult to control the curvature of the leading edge curve between two points. Therefore, the present invention selects four profiles to form the stator.

[0026] Section 1 is used as the fixed end, and Section 4 is the distal end. By defining the distance relationship between Section 1 and Section 4 in the length direction, it can adapt to the oncoming flow velocity direction in front of the stern propeller of the above-mentioned bulk carriers, oil tankers, and container ships. When the stator length is approximately equal to 1 times the propeller radius, Section 4, Section 3, Section 2, and Section 1 respectively correspond to approximately 1 times the radius, approximately 0.75 times the radius, approximately 0.5 times the radius, and the hull. Since the angle difference between the oncoming flow direction at 1 times the radius of the left hull of a right-handed propeller ship and the oncoming flow direction at 0.5 times the radius of the propeller is usually less than the angle difference between the oncoming flow direction at 0.5 times the radius of the propeller and the oncoming flow direction at the hull, in order to adapt to the characteristics of the above oncoming flow direction: Sections 4, 3, and 2 are arranged close to the distal end in the length direction, and the distance between them in the length direction is one-fourth of the stator length direction length. Sections 4, 3, and 2 are relatively close and the rotation angles are all 1 to 2 degrees or not rotated. Sections 4, 3, and 2 control the included angle between the distal half of the stator and the oncoming flow. The stator between Sections 4, 3, and 2 corresponds to the oncoming flow between 1 times the radius of the propeller and 0.5 times the radius of the propeller. Section 3 is used to control the part between Section 2 and Section 4 to ensure that the rotation angle of the stator between Section 2 and Section 4 is the required angle by the designer. The distance between Section 1 and Section 2 is relatively large, and the distance between them in the length direction is one-half of the stator length direction length. The rotation angle difference between Section 1 and Section 2 can reach 9 degrees (when Section 1 rotates 10 degrees, Section 2 rotates 1 degree). Sections 1 and 2 control the included angle between the hull-proximal half of the stator and the oncoming flow. The stator between Sections 1 and 2 corresponds to the oncoming flow between 0.5 times the radius of the propeller and the hull. The curvature change of the leading edge curve between Section 1 and Section 2 is greater than the curvature change of the leading edge curve between Section 2 and Section 4. In order to reduce the workload of smoothing the leading edge curve; the present invention does not add a fifth section between Section 1 and Section 2. If a fifth section is added between Section 1 and Section 2, additional time-consuming and laborious adjustments are required to ensure the curve smoothness of the aforementioned leading edge curve.

[0027] And for bulk carriers, oil tankers or container ships, the rotation direction and angle of these four sections can achieve a relatively good improvement in propulsion efficiency. Under this limitation, each section is rotated by the designer by the required angle according to the oncoming flow direction at the corresponding position so that the included angle with the oncoming flow reaches the design value. When the included angle reaches this design value, the stator can deflect the oncoming flow about to flow through the propeller, enabling the propeller blades to work in a more favorable environment, thereby improving the propeller propulsion efficiency. At the same time, this design value of the included angle should avoid a significant increase in the resistance of the stator. Therefore, when the increase ratio of the resistance is less than the increase ratio of the propeller efficiency, the purpose of improving the ship's propulsion efficiency and saving energy and reducing emissions is achieved. The specific design method for determining the design value of the included angle is the rapid ship model test in a water tank or CFD. Description of the Drawings

[0028] Figure 1Schematic diagram of the structure of the stator in a specific embodiment;

[0029] Figure 2 is Figure 1 front view of the stator of;

[0030] Figure 3 is Figure 1 top view of the stator of;

[0031] Figure 4 is Figure 1 left view of the stator of;

[0032] Figure 5 Schematic diagram of the structure of a specific embodiment of the stator type ship propulsion efficiency improvement device prepared;

[0033] Figure 6 Schematic diagram of the structure of another specific embodiment of the stator type ship propulsion efficiency improvement device prepared.

[0034] Figures 1-6 The reference numerals in are as follows:

[0035] 1 leading edge, 2 trailing edge, 3 stator, 4 propeller, 5 fixed end, 6 distal end, 7 section one, 8 section two, 9 section three, 10 section four, 11 duct. Specific embodiment

[0036] In order to make the objectives, technical solutions and advantages of the present invention clearer and more understandable, the following further details a stator type ship propulsion efficiency improvement device and a preparation method thereof 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 in a very simplified form and all use non-precise scales, only for the purpose of facilitating and clearly assisting in explaining the embodiments of the present invention. In order to make the objectives, features and advantages of the present invention more obvious and understandable, please refer to the accompanying drawings. It should be noted that the structures, scales, sizes, etc. shown in the drawings of this specification are only used to cooperate with the content disclosed in the specification for those familiar with this technology to understand and read, and are not used to limit the limiting conditions of the implementation of the present invention. Therefore, they do not have a technical essence. Any modification of the structure, change of the proportional relationship or adjustment of the size, without affecting the effects that the present invention can produce and the objectives that can be achieved, should still fall within the scope covered by the technical content disclosed by the present invention.

[0037] Combined with the attached Figures 1-6 , the present invention provides a preparation method of a stator type ship propulsion efficiency improvement device, including the following:

[0038] Define a length direction and a width direction that are perpendicular to each other, and the relative two ends along the width direction are the front part and the rear part respectively;

[0039] At least three profiles are arranged in sequence along the length direction. The dimensions in the width direction of the at least three profiles are the same. A leading edge 1 is formed by connecting the fronts of the at least three profiles with a spline curve, and a trailing edge 2 is formed by connecting the rears of the at least three profiles with a straight line. The at least three profiles are all perpendicular to the trailing edge 2. A geometric surface is formed by lofting a surface along the leading edge 1 and the trailing edge 2 from the at least three profiles;

[0040] The at least three profiles are respectively rotated in a required direction and by a required angle to form a stator 3. The required direction and the required angle are determined as follows: Obtain a plurality of oncoming flow directions corresponding to different profiles, and rotate the corresponding profiles in the required direction and by the required angle so that a fixed preset included angle is presented with respect to the plurality of oncoming flows;

[0041] The above-mentioned plurality of stators 3 are arranged in front of a propeller 4. The front is the bow direction of the ship. The two ends of the stator 3 along its length direction are respectively a fixed end 5 and a distal end 6. The fixed end 5 is fixedly connected to the hull in front of the propeller 4, the distal end 6 is far from the hull, and the plurality of stators 3 are arranged at intervals in the circumferential direction. The circumferential direction is defined based on the rotation direction of the propeller 4.

[0042] In a specific embodiment, the ship is a bulk carrier or an oil tanker or a container ship, and the propellers 4 of these ships are usually installed behind the stern shaft outlet of the hull;

[0043] Four profiles are arranged in sequence along the length direction, namely profile one 7, profile two 8, profile three 9 and profile four 10. The profile one 7 is the fixed end 5, and the profile four 10 is the distal end 6;

[0044] The profile one 7 is rotated 6 to 10 degrees counterclockwise with the trailing edge 2 as the axis, the profile two 8 is rotated 1 to 2 degrees counterclockwise with the same axis, and the profile three 9 and the profile four 10 are not rotated or rotated 1 to 2 degrees clockwise with the same axis. The definitions of clockwise and counterclockwise are as follows: Make a fist with the right hand and extend the thumb. The thumb points from the profile one 7 to the profile four 10 along the trailing edge. At this time, the direction of rotation along the four fingers of the right hand around the thumb is the clockwise rotation, and the rotation direction opposite to the clockwise rotation is the counterclockwise rotation.

[0045] In this specific embodiment, the length of the stator 3 is defined as follows: The length of the stator 3 is not greater than the radius of the circle swept by the tip of the propeller 4 during rotation and not less than 0.9 times the radius of the circle swept by the tip of the propeller 4 during rotation;

[0046] The distances from Section 1-7 to Section 4-10 are defined as follows: Section 1-7 and Section 4-10 are located at the two ends of the stator 3 along its length direction. Section 2-8 is located at the midpoint of the line connecting Section 1-7 and Section 4-10 in the length direction. Section 3-9 is located at the midpoint of the line connecting Section 2-8 and Section 4-10 in the length direction.

[0047] In this manufacturing method, different torsional angles can be set at different positions of the stator 3, enabling adaptation to the oncoming flow direction at different positions, thereby deflecting the oncoming flow so that the oncoming flow entering the propeller is in a more favorable direction and angle for the propeller blades, making the oncoming flow more conducive to the generation of lift by the propeller blades and being better applicable to the stern flow under the combined influence of the propeller rotation and the hull geometry.

[0048] The oncoming flow velocity directions in front of the stern propellers of bulk carriers, tankers, and container ships exhibit the following characteristics: For a right-handed propeller ship, the oncoming flow directions at a distance of 1 propeller radius from the left side of the hull and at a distance of 0.5 propeller radii from the propeller are relatively close. Usually, their projections on the ship's mid-longitudinal section differ by 2 to 4 degrees. The angle difference between the oncoming flow at 0.5 propeller radii from the propeller and the oncoming flow near the hull is relatively large. The projection of the oncoming flow direction near the hull on the ship's mid-longitudinal section may differ by 10 degrees from the projection of the oncoming flow direction at 0.5 propeller radii from the propeller.

[0049] Selecting four sections for manufacturing can better adapt to the oncoming flow. To adapt to the oncoming flow direction, when the four sections are rotated by different angles, the fronts of the four sections are connected by a spline curve to form a leading edge curve. At this time, the leading edge curve has 4 points for designers to adjust the curve curvature. Having too many points passed by the leading edge curve is not conducive to ensuring the smoothness of the leading edge curve; while when there are only three sections, the number of points passed by the leading edge curve is too small, making it difficult to control the curvature of the leading edge curve between two points. Therefore, the present invention selects four sections to form the stator.

[0050] Profile 1-7 serves as the fixed end 5, and Profile 4-10 is the distal end 6. By defining the distance relationship between Profile 1-7 and Profile 4-10 in the length direction, it can adapt to the oncoming flow velocity direction of the stern propeller of the above-mentioned bulk carriers, oil tankers, and container ships. When the stator length is approximately equal to 1 times the propeller radius, Profile 4-10, Profile 3-9, Profile 2-8, and Profile 1-7 respectively correspond to approximately 1 times the radius, approximately 0.75 times the radius, approximately 0.5 times the radius, and the hull. Since the angle difference between the oncoming flow direction at 1 times the radius of the left hull of a right-handed propeller ship and the oncoming flow direction at 0.5 times the radius of the propeller is usually less than the angle difference between the oncoming flow direction at 0.5 times the radius of the propeller and the oncoming flow direction at the hull, in order to adapt to the characteristics of the above oncoming flow direction: Profiles 4, 3, and 2 are arranged close to the distal end in the length direction, and the distance between them in the length direction is one-fourth of the stator length direction length. Profiles 4, 3, and 2 are relatively close and the rotation angles are all 1 to 2 degrees or not rotated. Profiles 4, 3, and 2 control the included angle between the proximal half of the stator and the oncoming flow. The stator between Profiles 4, 3, and 2 corresponds to the oncoming flow between 1 times the radius of the propeller and 0.5 times the radius of the propeller. Profile 3-9 is used to control the part between Profile 2-8 and Profile 4-10 to ensure that the rotation angle of the stator between Profile 2-8 and Profile 4-10 is as required by the designer. The distance between Profile 1-7 and Profile 2-8 is relatively large, and the distance between them in the length direction is one-half of the stator length direction length. The rotation angle difference between Profile 1-7 and Profile 2-8 can reach 9 degrees (when Profile 1 rotates 10 degrees, Profile 2 rotates 1 degree). Profile 1-7 and Profile 2-8 control the included angle between the proximal half of the stator close to the hull and the oncoming flow. The stator between Profiles 1 and 2 corresponds to the oncoming flow between 0.5 times the radius of the propeller and the hull. The change in the curvature of the leading edge curve between Profile 1-7 and Profile 2-8 is greater than the change in the curvature of the leading edge curve between Profile 2-8 and Profile 4-10. In order to reduce the workload of smoothing the leading edge curve; the present invention does not add a fifth profile between Profile 1-7 and Profile 2-8. If a fifth profile is added between Profile 1-7 and Profile 2-8, the aforementioned leading edge curve requires additional adjustment to ensure curve smoothness, which is time-consuming and laborious.

[0051] And for bulk carriers, oil tankers or container ships, the rotation direction and angle of the four profiles can achieve a relatively optimal propulsion efficiency improvement. Under this limitation, each profile is rotated by the designer by the required angle according to the oncoming flow direction at the corresponding position so that the included angle with the oncoming flow reaches the design value. When the included angle reaches this design value, the stator can deflect the oncoming flow about to flow through the propeller, enabling the propeller blades to work in a more favorable environment, thereby improving the propulsion efficiency of the propeller 4. At the same time, this design value of the included angle should avoid a significant increase in the resistance of the stator. Therefore, when the increase ratio of the resistance is less than the increase ratio of the propeller efficiency, the purpose of improving the ship's propulsion efficiency and saving energy and reducing emissions is achieved. The specific design method for determining the design value of the included angle is the rapid ship model test in a water tank or CFD.

[0052] In a specific embodiment, for a right-handed propeller, the plurality of stators 3 are arranged on the left upper side of the hull in front of the propeller 4, and the directions are as follows: with the port side of the hull as the left, the gravity direction as the lower, and the direction opposite to the gravity direction as the upper; or

[0053] For a left-handed propeller, the plurality of stators 3 are arranged on the right upper side of the hull in front of the propeller 4, and the directions are as follows: with the starboard side of the hull as the right, the gravity direction as the lower, and the direction opposite to the gravity direction as the upper.

[0054] Combined with Figure 6 , in a specific embodiment, a duct 11 is arranged at the distal end of each of the plurality of stators 3, and the distal ends 6 are fixedly connected to the inner surface of the duct 11.

[0055] In a specific embodiment, the number of the stators 3 is 3 or 4.

[0056] Among them, the plurality of oncoming flow directions are obtained through a water tank PIV test or CFD.

[0057] In a specific embodiment, the geometric surface is smoothed by adjusting the curvature.

[0058] The present invention also provides a stator type ship propulsion efficiency improvement device prepared by using any one of the above preparation methods.

[0059] The technical features of the above embodiments can be combined arbitrarily. For the sake of concise description, not all possible combinations of the technical features in the above embodiments are described. However, as long as there is no contradiction in the combination of these technical features, it should be considered as the scope described in this specification.

[0060] The above embodiments only represent several implementation manners of the present invention, and their descriptions are relatively specific and detailed, but they should not be construed as limiting the scope of the invention patent. It should be noted that for those of ordinary skill in the art, without departing from the concept of the present invention, several deformations and improvements can still be made, and these all belong to the protection scope of the present invention. Therefore, the protection scope of the invention patent should be subject to the appended claims.

Claims

1. A preparation method of a stator-type ship propulsion efficiency improvement device, characterized in that It includes the following: Define a length direction and a width direction that are perpendicular to each other. The relative two ends along the width direction are the front part and the rear part respectively; Arrange at least three profiles in sequence along the length direction. The dimensions of these at least three profiles in the width direction are the same. Connect the front parts of these at least three profiles with a spline curve to form a leading edge, and connect the rear parts of these at least three profiles with a straight line to form a trailing edge. These at least three profiles are all perpendicular to the trailing edge. A geometric surface is formed by lofting the surface along the leading edge and the trailing edge with these at least three profiles; Rotate the at least three profiles respectively in the required direction and at the required angle to form stators. The required direction and the required angle are determined as follows: Obtain several oncoming flow directions corresponding to different profiles, and rotate the corresponding profiles in the required direction and at the required angle so that a fixed preset included angle is presented with respect to several oncoming flows; Arrange the above-mentioned several stators in front of the propeller. The front is the bow direction of the ship. The two ends of the stator along its length direction are the fixed end and the distal end respectively. Fix the fixed end to the hull in front of the propeller, and the distal end is far from the hull. And arrange these several stators at intervals in the circumferential direction, and the circumferential direction is defined based on the rotation direction of the propeller.

2. The preparation method of the stator type ship propulsion efficiency improvement device according to claim 1, wherein: The ship is a bulk carrier or an oil tanker or a container ship, and the propellers of these ships are installed behind the stern shaft outlet of the hull; Arrange four profiles in sequence along the length direction, namely profile one, profile two, profile three and profile four. Profile one is the fixed end, and profile four is the distal end; Profile one rotates 6 to 10 degrees counterclockwise with the trailing edge as the axis, profile two rotates 1 to 2 degrees counterclockwise with the same axis, and profile three and profile four do not rotate or rotate 1 to 2 degrees clockwise with the same axis. Define clockwise and counterclockwise as follows: Make a fist with the right hand and stretch out the thumb. The thumb points from profile one to profile four along the trailing edge. At this time, the direction of rotation along the four fingers of the right hand around the thumb is the clockwise rotation, and the rotation direction opposite to the clockwise rotation is the counterclockwise rotation.

3. The preparation method of the stator-type ship propulsion efficiency improvement device according to claim 2, characterized in that, Define the length of the stator: The length of the stator is not greater than the radius of the circle swept by the tip of the propeller blade during rotation and not less than 0.9 times the radius of the circle swept by the tip of the propeller blade during rotation; The distances between profile one and profile four are defined as follows: Profile one and profile four are located at the two ends of the stator along its length direction. Profile two is located at the midpoint of the line connecting profile one and profile four in the length direction, and profile three is located at the midpoint of the line connecting profile two and profile four in the length direction.

4. The preparation method of the stator type ship propulsion efficiency improvement device according to claim 3, wherein: For a right-handed propeller, the several stators are arranged on the upper left of the hull in front of the propeller. The directions are: with the left side of the hull as the left, the gravity direction as the lower, and the direction opposite to the gravity direction as the upper; Or For a left-handed propeller, the several stators are arranged on the upper right of the hull in front of the propeller. The directions are: with the right side of the hull as the right, the gravity direction as the lower, and the direction opposite to the gravity direction as the upper.

5. The preparation method of the stator type ship propulsion efficiency improvement device according to claim 4, characterized in that, A conduit is arranged at the distal end of each of the plurality of stators, and the distal ends are fixedly connected to the inner surface of the conduit.

6. The preparation method of the stator-type ship propulsion efficiency improvement device according to claim 4, characterized in that, The number of the stators is three or four.

7. The preparation method of the stator type ship propulsion efficiency improvement device according to claim 1, characterized in that, The plurality of oncoming flow directions are obtained through a water tank PIV test or CFD.

8. The preparation method of the stator type ship propulsion efficiency improvement device according to claim 1, characterized in that, The geometric surface is smoothed by adjusting the curvature.

9. A stator-type device for improving the propulsion efficiency of a ship, characterized in that, It is prepared by using the preparation method according to any one of claims 1-8.

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