KR20050118883A - The propeller trailing edge to minimize the noise and vibration of the blade - Google Patents

Abstract

The present invention is to reduce the vibration and noise caused by the peeling phenomenon occurring at the end of the propeller (propeller, screw, fan) used in a variety of machines such as propulsion equipment or fluid pump used in ships or aircraft In the processing of the end of the to provide a way to solve the problem through the attachment of the dissimilar material rather than the processing through grinding.

In order to achieve the above object, the present invention is composed of a method of attaching a different material to the material of the wing by the curing method by welding rather than polishing to the end of the wing according to each object and the technical Make a point.

Description

Propeller Trailing Edge to minimize the noise and vibration of the blade}

The present invention relates to a method of manufacturing a technology related to the suppression of vibration and noise generated from a propeller, a screw, a fan, etc. More specifically, the existing method is a propeller to suppress the noise and vibration It has been suppressed by vibration and noise by the deformation of the blade tip. However, the present invention relates to a technique for reducing or eliminating side effects as they occur. Typically, if there is a fixed object while the fluid (materials that can flow fluidly, such as gas or liquid), or the object covers the fluid, the fluid may be in the inflow 101 as shown in FIG. Separation (103) is performed due to the viscosity of the fluid (Viscosity) in the object 102, the separation phenomenon proceeds in a spiral vortex 104 (Vortex).

When this phenomenon is applied to the wing portion of the propeller, the inflow 201 flows along the surface of the wing 202 as shown in FIG. 2 and the flow of oil 203 reaches the trailing edge of the wing. Peeled vortex 204 is created. The propeller's wing receives the physical force by the fluid force generated by the above phenomena, and the physical force caused by this fluid force vibrates the entire wing starting at the tip of the wing of the propeller in the fluid. If the vibration period of the vibrating wing due to (Exciting Force) coincides with the vibration period of the vortex due to peeling and peeling, resonance occurs between the wing and the fluid, which causes amplified vibration. . The vibration generated in this way generates noise, and this noise is called Singing in ship terminology, and is mainly generated in propellers used as propulsion devices for ships or airplanes. The noise and vibration generated accelerate the internal fatigue failure due to the constant vibration in the propeller, which degrades durability. In addition, additional damages are caused by the noise generated, and the users of the ship are not guaranteed a pleasant working environment due to noise, which reduces efficiency, exposes them to various diseases caused by noise, and requires confidentiality or low noise depending on the purpose of the vessel. For example, military ships (submarines, infiltration ships, combat ships ...) or fishing vessels for catching noise-sensitive fish make noise difficult to serve their own purposes.

Vortex morphology, vibration, and noise caused by this delamination do not have regular rules, and even if they are perfectly symmetrical, they show different results, and current phenomena cannot predict this phenomenon. However, if the surface shape of the tip of the wing is polished to a certain shape and deformed, the peeling phenomenon and the vortices, which cause noise and vibration, will be reduced. However, if it does not disappear, change the shape by grinding until it disappears and continue processing. Such machining is commonly referred to as anti-singing edge and is processed as shown in Figure 4, but the anti-inging edge form shown in Figure 4 is a few examples of high noise rejection. In fact, the ends must be machined in various forms until noisy. Direct machining at these ends increases the number of parts lost during machining due to the nature of the grinding process, and excessive machining affects the propeller shape of the original design, affecting performance, affecting durability or even remanufacturing. There may be Even if the noise is removed after this operation, noise and vibration may occur again due to the deposition, abrasion, or distortion of foreign matter during use, and if this happens, the end part should be processed again. In addition, the end of the propeller, which is already weakened due to machining, is deformed again and the vicious cycle of processing is repeated to shorten the life of the propeller.

As a method for making such anti-singing edges, the existing method of grinding the propeller not only affects the performance or the durability of the propeller itself, but also has to do so until the result is satisfactory. There is a problem that needs to be discarded and newly manufactured. Therefore, the present invention is to solve the problem that occurs when using the method as described above in the processing to remove or reduce the noise and vibration by changing the natural frequency of the blade through the attachment of a dissimilar material rather than polishing. To provide.

In order to achieve the above object, in the method of processing the propeller end, attaching different materials (metal or material of sufficient strength to the propeller and other materials) to the end of the wing of the propeller (welding curing method or other joining method) Method and characterized by such a configuration.

First, the configuration of the present invention will be described in detail with reference to FIGS. 5 to 7, 8 to 10, and 11 to 14 to FIG. 5 to 7. As shown in FIGS. 8 through 10, the attachment is performed in various forms in the same process as in FIG. 11 through FIG. 14, and according to the purpose of use, first, at the position 503 illustrated in FIG. 5. Attached and having a cross-sectional shape as shown in FIG. 8 and manufactured in the same process as in FIG. 11 are heterogeneous materials attached to the blades 111 that are not resolved despite the anti-singing edge. ) And polish it along the face of the wing (113) and process the end portion in the form of anti-singing edge (114) as an example. At this time, the shape of the anti-singing edge to be processed changes the shape until the problem is solved in various shapes in consideration of the characteristics of the sound phenomenon and the mechanical properties of the fluid.

Secondly, the process attached to the position illustrated in FIG. 6 and manufactured by the cross-sectional shape as shown in FIG. 9 and the process as shown in FIG. 12 is suitable for the vibration and the loudness of the resulting loudness. ), Attaching different materials (603, 122) between 0.1% to 30% of the total length of the blade and processing the thickness and shape of the attachment surface (123,124). In addition, in consideration of the sound and hydrodynamic characteristics, the distance from the tip of the wing, the width and thickness of the attachment surface, and the shape of the cross section are varied until the noise is removed or optimally reduced. The reason why the sound phenomenon is reduced or eliminated by this treatment is not technically determined yet, but it is very effective in the above processing.

Third, the process attached to the position illustrated in FIG. 7 and having the same cross-sectional shape as FIG. 10 and manufactured by the process as shown in FIG. 13 is performed by cutting a part of the blade tip to a certain width (704, 132) when a noise phenomenon occurs. After attaching the material of the wing and other heterogeneous materials to the cut portion (133) and the polishing along the surface of the wing (134) and then the end portion is processed in the form of anti-singing edge (134, 135). In the case of such processing, if the end part is injured internally and externally due to frequent grinding process, or if the end part of the wing is deformed according to the original purpose, cutting and processing this part greatly affect the wing body and structure. Modifications can be made continuously without giving a warning.

Fourth, it is attached to the position illustrated in FIG. 7 and has the same cross-sectional shape as in FIG. 10, but is manufactured in the same process as in FIG. 14. The above processing is based on the premise of attaching dissimilar materials from the design of the wing. Designed to have a shape without end (141) and attaches the material of the wing and other heterogeneous materials to the produced wing (142), and then polished along the surface of the wing (143) and then ends in the form of anti-singing edges. The parts are machined (144, 155). Such a method can simplify the process that can be complicated due to the existing design in forming the anti-singing edge, and the end portion can be continuously modified without affecting the wing body and structure.

As described above, the present invention accelerates the aging phenomenon due to noise and vibration occurring in devices using propellers, fans, screws, and the like, direct and indirect damage due to noise, and vibrations applied to the main body as the vibrations of the ends are amplified. To solve the problems of the wing tip by changing the natural frequency of the wing by attaching dissimilar materials instead of polishing, it solves the problems such as the difference from the existing design purpose and the durability reduction due to the polishing caused by the conventional polishing. Can be. In particular, the basic shape of the existing wings can be maintained intact, and the heterogeneous material can be deformed at any time by processing the welding curing method, thus making it more versatile and easier to solve the problems caused above.

1 is a view explaining peeling and vortex phenomena occurring around a simple object

2 is a view illustrating peeling and vortex phenomena occurring at the tip of the blade;

Figure 3 explaining the shape and terminology of the propeller

Fig. 4 Various examples of conventional anti-singing edges processed by grinding

5 is a view showing a position and an example of attachment of the dissimilar material in the form shown in Figure 8 to the wing of the propeller

6 is a view showing a position and an example of attachment of the dissimilar materials in the form shown in Figure 9 on the wing of the propeller

7 is a view showing a position and an example of attachment of the dissimilar material in the form shown in Figure 10 to the wing of the propeller

8 is a view illustrating a method of attaching a heterogeneous material in various forms to a wing end of an existing anti-singing edge through a cross section of the wing;

9 is a diagram illustrating a method of attaching heterogeneous materials in various forms to the wing tip when the amplitude of the sound and vibration of the wing tip is large through the cross section of the wing;

10 is a view illustrating a method of attaching a dissimilar material in various forms to the end of the wing made in consideration of the application of the invention when cutting a portion or design of the wing through a cross section of the wing

11 is a view illustrating a process of attaching and processing a dissimilar material on the wing tip that has been previously processed anti-singing edge

12 is a view illustrating a process of attaching and processing a dissimilar material on the blade tip when the amplitude of the sound and vibration of the blade tip is large.

13 is a view illustrating a process of attaching and processing a dissimilar material on the wing tip after cutting a portion of the wing tip

14 is a view illustrating a process of attaching and processing a dissimilar material on the wing tip made in consideration of the application of the invention in the design

Figure 15 underwater radiation noise characteristics before the invention is applied

Fig. 16 Underwater radiation noise characteristics improved by the application of the invention

<Description of reference numerals for main parts of the drawings>

101) Inflows 102) Objects

103) Separation 104) Vortex

201) Inflow 202) Wings

203) Flow of oil 204) Peeled vortex

301) Propeller wing 302) Cross section of wing

303) Leading Edge 304) Trailing Edge

Propeller Wings

Leading Edge

503,603,703) Additional Materials

504,604,704) Trailing Edge

801) Additional Materials

802) Trailing Edge

1101) wing 11602) attached heterogeneous material

113) Polished and missing parts

111) ~ 145) Process of Wings

Claims (3)

Attaching a metal of a propeller blade and a different material to the outside of the propeller blade (112, 122, 134, 142), and polishing the portion of the dissimilar material to which the metal is attached to match the propeller blade (113, 123, 135, 143), and a step (114, 124, 136, 144) of grinding the end of the propeller containing the processed dissimilar material portion to a predetermined shape, polishing with an anti-singing edge, characterized in that it comprises a End treatment method for propeller vane vibration and noise suppression The method of claim 1, wherein the dissimilar material is attached between 0.1% and 30% of the entire length of the blade from the blade tip. The propeller is formed so that a part of the wing tips 131 and 141 of the propeller is cut (132, 133, 141 and 704), and a different material different from the wing material is attached to the wing tip (134, 142, 703) Ends for propeller blade vibration and noise suppression, characterized in that the heterogeneous material attached to the purpose of the wing (135, 143) and then processed by anti-singing edge (136, 137, 144, 145) Processing method