Energy-saving twisted rudder

Abstract

The utility model belongs to the technical field of ship manufacturing, and discloses an energy-saving twisted rudder which is characterized in that the front side of a rudder blade is an inclined edge shrunk inwards from top to bottom, the rear side of the rudder blade is a vertical edge, the rudder blade is of an NACA airfoil profile, the maximum thickness of the rudder blade is gradually reduced from top to bottom, and the rudder blade is of a three-section structure which is detachably and fixedly connected and comprises an upper blade part, a twisted blade part and a lower blade part from top to bottom; the rudder ball part is detachably, horizontally and fixedly connected to the position, located on the axis of the propeller shaft, of the torsion blade part, the upper portion and the lower portion of the front end of the torsion blade part are twisted towards the portboard side and the starboard side respectively along the central axis of the rudder ball part, and through the three-section detachable design of the rudder blade, assembly and later maintenance and replacement of all assemblies of the rudder blade and the rudder ball are facilitated; meanwhile, the torsion degree of the rudder body can be adjusted by replacing the torsion blade part; and through the twisting arrangement of the rudder body and the rudder ball, the wake flow is rectified, and the energy-saving effect is further improved.

Description

Technical Field

[0001] The present application relates to the technical field of shipbuilding, and more specifically, to an energy-saving twisted rudder. Background Art

[0002] The twisted rudder is a highly efficient reaction rudder that makes full use of the propeller wake and improves the coordination between the propeller and the rudder. About 15%-30% of the total energy of the hull propeller remains in the wake field in the form of kinetic energy. The induced speed generated by the propeller at different rudder heights is different in magnitude and direction. The design of the twisted rudder deflects the blade section of the rudder at different heights by a certain angle according to the direction of the incoming flow, so that each rudder blade section can obtain a more favorable incoming flow attack angle, thereby obtaining additional lift and additional resistance, and the combined force is the additional thrust. The twisted rudder can reduce or even eliminate cavitation erosion similar to ordinary balanced rudders, and has a good energy-saving effect. Summary of the invention

[0003] In order to solve the above problems, the present application provides an energy-saving twisted rudder.

[0004] The energy-saving twisted rudder provided in this application adopts the following technical solution:

[0005] An energy-saving twisted rudder comprises a vertically arranged rudder blade and a rudder bar whose upper end is used for rotationally cooperating with the tail of a hull, the front side of the rudder blade is an inclined edge that shrinks inward from top to bottom, and the rear side is a vertical edge, the rudder blade is a NACA airfoil, and its maximum thickness gradually decreases from top to bottom, the rudder blade is a three-section structure that can be detachably fixedly connected, and from top to bottom, they are an upper blade part, a twisted blade part and a lower blade part, the twisted blade part is detachably and horizontally fixedly connected with a rudder ball part at a position located on the axis of a propeller shaft, the upper and lower parts of the front end of the twisted blade part are twisted toward the port side and the starboard side respectively along the central axis of the rudder ball part, so that the orthographic projections of the leading edge vertices of the twisted blade part are distributed in a tangent function curve, and the upper blade part and the lower blade part are smoothly transitioned and extended along the upper and lower ends of the twisted blade part respectively.

[0006] Furthermore, the angle α1 between the chord of the horizontal section of the upper blade and the chord of the horizontal section of the twisted blade along the axis of the rudder bulb is 2° to 4°.

[0007] Furthermore, the angle α2 between the chord of the horizontal section of the lower blade and the chord of the horizontal section of the twisted blade along the axis of the rudder bulb is 2° to 4°.

[0008] Furthermore, the length ratio of the side projection of the twisted blade portion along the axis of the rudder bulb portion is 1.4 to 1.6.

[0009] Furthermore, the ratio of the maximum diameter of the rudder bulb to the blade diameter is 0.18 to 0.2.

[0010] In summary, the present application includes at least one of the following beneficial technical effects:

[0011] The three-section detachable design of the rudder blade facilitates the assembly and subsequent maintenance and replacement of the rudder blade and rudder ball components. At the same time, the torsion of the rudder body can be adjusted by replacing the torsion blade. Through the torsion setting of the rudder body, the twisted guide edge adapts to the incoming flow direction, rectifies the wake, suppresses the rotation of the wake, increases the axial induced speed of the propeller, and generates additional thrust, which is equivalent to recovering the rotational kinetic energy of the wake, thereby improving the propulsion efficiency. At the same time, the propeller hub vortex is eliminated by the rudder ball, further improving the energy-saving effect. According to actual ship application tests, ships with Fourier numbers above 0.185 can save more than 3% energy by using this twisted reaction rudder compared to traditional rudder bodies. BRIEF DESCRIPTION OF THE DRAWINGS

[0012] Figure 1 This is a schematic diagram of the structure of this application;

[0013] Figure 2 is a schematic diagram of the three-dimensional structure of the rudder blade;

[0014] Figure 3 This is the front side view of the rudder blade;

[0015] Figure 4 This is a bottom view of the rudder blade.

[0016] Description of the numbers in the figure:

[0017] 1. Rudder blade; 11. Upper blade; 12. Twisting blade; 13. Lower blade; 2. Rudder stock assembly; 3. Rudder ball; 4. Hull; 5. Propeller shaft; 6. Propeller blade. DETAILED DESCRIPTION

[0018] The technical solutions in the embodiments of the present application will be clearly and completely described below in conjunction with the drawings in the embodiments of the present application; obviously, the described embodiments are only part of the embodiments of the present application, rather than all the embodiments, and all other embodiments obtained by ordinary technicians in this field based on the embodiments in the present application without making creative work are within the scope of protection of the present application.

[0019] In the description of the present application, it should be noted that the terms "upper", "lower", "inner", "outer", "top / bottom" and the like indicate positions or positional relationships based on the positions or positional relationships shown in the drawings, and are only for the convenience of describing the present application and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific position, be constructed and operated in a specific position, and therefore cannot be understood as limiting the present application. In addition, the terms "first" and "second" are used for descriptive purposes only, and cannot be understood as indicating or implying relative importance.

[0020] In the description of this application, it should be noted that, unless otherwise clearly specified and limited, the terms "installed", "provided with", "set / connected", "connected", etc. should be understood in a broad sense. For example, "connected" can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be a direct connection, or it can be indirectly connected through an intermediate medium, or it can be the internal communication of two components. For ordinary technicians in this field, the specific meanings of the above terms in this application can be understood according to specific circumstances.

[0021] Embodiment 1:

[0022] The following is combined with Figure 1-4 This application is described in further detail.

[0023] The embodiment of the present application discloses an energy-saving twisted rudder, comprising a vertically arranged rudder blade 1 and a rudder stock at the upper end of which is used to rotate with the tail of a hull 4, the front side of the rudder blade 1 is an inclined edge that shrinks inward from top to bottom, and the rear side is a vertical edge, the rudder blade 1 is a NACA airfoil, and its maximum thickness gradually decreases from top to bottom, the rudder blade 1 is a three-section structure that can be detachably fixed and connected, connected by welding or bolts, and from top to bottom are an upper blade portion 11, a twisted blade portion 12 and a lower blade portion 13, the twisted blade portion 12 is detachably and horizontally fixedly connected with a rudder ball portion 3 at a position located on the axis of a propeller shaft 5, the upper and lower parts of the front end of the twisted blade portion 12 are twisted toward the port and starboard sides respectively along the central axis of the rudder ball portion 3, so that the orthographic projections of the leading edge vertices of the twisted blade portion 12 are distributed in a tangent function curve, and the upper blade portion 11 and the lower blade portion 13 are smoothly transitioned and extended along the upper and lower ends of the twisted blade portion 12 respectively.

[0024] See also Figure 4 The angle α1 between the chord of the horizontal section of the upper blade 11 and the chord of the horizontal section of the torsion blade 12 along the axis of the rudder ball part 3 is 3°, and the angle α2 between the chord of the horizontal section of the lower blade 13 and the chord of the horizontal section of the torsion blade 12 along the axis of the rudder ball part 3 is 3°.

[0025] See also Figure 1-3 The length ratio of the side projection of the torsion blade along the axis line of the rudder bulb part 3 is 1.6.

[0026] See also Figure 1 The ratio of the maximum diameter of the rudder bulb 3 to the diameter of the blade 6 is 0.19.

[0027] The implementation principle of an energy-saving twisted rudder in the embodiment of the present application is:

[0028] The three-section detachable design of the rudder blade 1 facilitates the assembly and subsequent maintenance and replacement of the rudder blade 1 and the rudder ball. At the same time, the torsion degree of the rudder body can be adjusted by replacing the torsion blade 12. Through the torsion setting of the rudder body, the twisted guide edge adapts to the incoming flow direction, the wake is rectified, the rotation of the wake is suppressed, the axial induced speed of the propeller is increased, and additional thrust is generated, which is equivalent to recovering the rotational kinetic energy of the wake, thereby improving the propulsion efficiency. At the same time, the propeller hub vortex is eliminated by the rudder ball, further improving the energy-saving effect. According to actual ship application tests, after the twisted reaction rudder is applied to ships with Fourier numbers above 0.185, more than 3% of energy can be saved compared with traditional rudder bodies.

[0029] The above are all preferred embodiments of the present application, and the protection scope of the present application is not limited thereto. Therefore, any equivalent changes made according to the structure, shape, and principle of the present application should be included in the protection scope of the present application.

Claims

1. An energy-saving twisted rudder, comprising a vertically arranged rudder blade (1) and a rudder stock assembly (2) whose upper end is used to rotate with the stern of a ship, characterized in that: The front side of the rudder blade (1) is an inclined edge that contracts inward from top to bottom, and the rear side is a vertical edge. The rudder blade (1) is a NACA airfoil, and its maximum thickness gradually decreases from top to bottom. The rudder blade (1) is a three-section structure that can be detachably fixedly connected, and from top to bottom, it is an upper blade part (11), a twisted blade part (12) and a lower blade part (13). The twisted blade part (12) is detachably and horizontally fixedly connected to a rudder ball part (3) at a position located on the axis of the propeller shaft. The upper and lower parts of the front end of the twisted blade part (12) are twisted toward the port side and the starboard side respectively along the central axis of the rudder ball part (3), so that the orthographic projections of the leading edge vertices of the twisted blade part (12) are distributed in a tangent function curve. The upper blade part (11) and the lower blade part (13) are smoothly transitioned and extended along the upper and lower ends of the twisted blade part (12).

2. The energy-saving twisted rudder according to claim 1, characterized in that: The angle α1 between the chord of the horizontal section of the upper blade (11) and the chord of the horizontal section of the twisted blade (12) along the axis of the rudder bulb (3) is 2° to 4°.

3. The energy-saving twisted rudder according to claim 1, characterized in that: The angle α2 between the chord of the horizontal section of the lower blade (13) and the chord of the horizontal section of the twisted blade (12) along the axis of the rudder bulb (3) is 2° to 4°.

4. The energy-saving twisted rudder according to claim 1, characterized in that: The length ratio of the side projection of the twisted blade portion (12) along the axis of the rudder bulb portion (3) is 1.4 to 1.

6.

5. The energy-saving twisted rudder according to claim 1, characterized in that: The ratio of the maximum diameter of the rudder ball part (3) to the diameter of the blade is 0.18-0.2.

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