Lightweight noise reduction blade and blade lightweight noise reduction design method

Abstract

The quantitative noise reduction design method comprises the following steps that a circle of blades distributed in the circumferential direction are classified according to the bearing capacity, and multiple types of blades are obtained according to the difference of the bearing capacity; the hollow noise reduction blade design is adopted for the type of blades with the minimum bearing capacity, and the noise reduction design is not conducted on the type of blades with the maximum bearing capacity. The invention further provides a lightweight noise reduction blade, the blade comprises a blade body, a pair of cover plates, a silencing plate and a pair of honeycomb structures, and the blade body comprises a frame and a hollow cavity located in the frame; the pair of cover plates are arranged on the two sides of the blade respectively to seal the hollow cavity; the silencing plate is positioned in the hollow cavity and is arranged between the pair of cover plates; the pair of honeycomb structures is arranged between the cover plate and the silencing plate. According to the method, on the basis of classifying the blades, lightweight noise reduction design of the blades is carried out, safety is guaranteed, and the design target of lightweight noise reduction can be achieved.

Description

Technical Field

[0001] The present invention relates to the field of aeroengines, and in particular to the field of blade structure design. Background Art

[0002] With the development of aircraft engines, the design of integrating fan OGV and support plate has emerged. The integrated OGV support plate and blades not only play the role of transferring load bearing, but also serve as the outlet guide function. In addition, the fan outer OGV design also needs to have qualified noise reduction performance, such as noise reduction through fillers such as honeycomb structure.

[0003] However, noise reduction design and lightweight design are generally contradictory. The use of lighter materials and structural features often means that there will be safety issues such as insufficient structural rigidity and insufficient strength margin; while the use of noise reduction blade design means the introduction of noise absorbing materials or features in structural design and material application, which will increase the weight of the blade to a certain extent, and will also pose a higher challenge to overall safety. Summary of the invention

[0004] An object of the present invention is to provide a blade lightweight and noise reduction design method.

[0005] Another object of the present invention is to provide a lightweight, noise-reducing blade.

[0006] To achieve the above-mentioned purpose, the blade lightweight noise reduction design method includes the following steps: S1. Classifying a circle of blades distributed circumferentially according to the load-bearing weight, and obtaining multiple types of blades according to the different load-bearing weights; S2. Using hollow noise reduction blade design for the blade type with the least load-bearing weight, and not performing noise reduction design for the blade type with the largest load-bearing weight.

[0007] In order to achieve the above-mentioned purpose, a lightweight noise reduction blade adopts the above-mentioned method to obtain a type of blade with the least load-bearing capacity, which includes a blade body, a pair of cover plates, a silencer and a pair of honeycomb structures. The blade body includes a frame and a hollow cavity located in the frame; a pair of cover plates are respectively arranged on both sides of the blade to close the hollow cavity; the silencer is arranged between the pair of cover plates and is located in the hollow cavity; a pair of honeycomb structures are respectively arranged between the cover plates and the silencer plates.

[0008] In one or more embodiments, the cover plate is provided with a silencer hole corresponding to the honeycomb structure.

[0009] In one or more embodiments, the muffler hole provided on the cover plate on the back side of the blade is a conical hole with a cone angle of 45°.

[0010] In one or more embodiments, the honeycomb structure includes a plurality of honeycomb units, and each of the honeycomb units includes a central honeycomb located in the middle and an annular honeycomb surrounding the central honeycomb.

[0011] In one or more embodiments, each of the honeycomb units includes a sound-absorbing hole arranged on the cover plate, and a sound-transmitting hole arranged on the wall surface of the central honeycomb, and the sound-transmitting hole is used to connect the central honeycomb and each of the annular honeycombs.

[0012] In one or more embodiments, the cover plate is configured to be bonded to the honeycomb structure and the blade body by an adhesive film, and the honeycomb structure is configured to be bonded to the silencer plate by an adhesive film.

[0013] In one or more embodiments, the sound-absorbing plate is made of a resin composite material.

[0014] In one or more embodiments, the sound-absorbing plate is made of elastic material.

[0015] In one or more embodiments, the honeycomb structure is made of aluminum alloy honeycomb.

[0016] The above blade lightweight noise reduction design method is based on the subdivided blade load layout, and carries out noise reduction lightweight design for different blades according to the load capacity of different blades. The blades with the largest load capacity are not lightweighted to ensure the load-bearing function and safety of the blades. The blades with the smallest load capacity are hollowed out to achieve lightweighting through the hollow structure, and noise reduction is achieved through the silencer holes, honeycomb structure, and silencer plates on the cover. In this way, the lightweight and noise-reducing blade design is carried out efficiently under the premise of meeting safety requirements, solving the contradictions in traditional design. BRIEF DESCRIPTION OF THE DRAWINGS

[0017] The above and other features, properties and advantages of the present invention will become more apparent through the following description in conjunction with the accompanying drawings and embodiments, in which:

[0018] Figure 1 It is a schematic diagram of leaf classification;

[0019] Figure 2 is a component exploded view of an embodiment of a lightweight noise reduction blade;

[0020] Figure 3 is a transverse cross-sectional view of an embodiment of a lightweight noise reduction blade;

[0021] Figures 4A-4B It is a schematic diagram of a lightweight noise reduction blade;

[0022] Figure 5A-5B is a schematic diagram of a honeycomb structure;

[0023] Figure 6 This is the design structure diagram of the silencer hole of the cover;

[0024] Figure 7 yes Figure 6 Cross-section at the middle NN position;

[0025] Figure 8 It is a flow chart of the blade lightweight and noise reduction design method.

[0026] Symbols and Markings

[0027] 10 Blade body

[0028] 11. Border

[0029] 12 Hollow cavity

[0030] 20 Cover

[0031] 21 Leaf back cover

[0032] 22 Leaf basin cover

[0033] 30 Silencer

[0034] 40 Honeycomb structure

[0035] 41. Honeycomb on the back of the leaf

[0036] 42 Leaf basin side honeycomb

[0037] 44 Silencer hole

[0038] 45 Sound hole

[0039] 400 cells

[0040] 401 Cellular

[0041] 410 Center Cell

[0042] 420 Ring Cell DETAILED DESCRIPTION

[0043] The present invention is further described below in conjunction with specific embodiments and drawings. More details are elaborated in the following description to facilitate a full understanding of the present invention. However, the present invention can obviously be implemented in a variety of other ways different from the description herein. Those skilled in the art can make similar generalizations and deductions based on actual application situations without violating the connotation of the present invention. Therefore, the protection scope of the present invention should not be limited by the content of this specific embodiment.

[0044] It should be noted that these and other subsequent drawings are only examples and are not drawn to scale, and should not be used to limit the actual scope of protection required by the present invention.

[0045] The blade lightweight and noise reduction design method disclosed in the present invention can efficiently carry out lightweight and noise reduction blade design while meeting the safety requirements.

[0046] Firstly, a circle of blades distributed circumferentially are classified according to their load-bearing capacity, and multiple types of blades are obtained according to the different load-bearing capacity; then, a hollow noise reduction blade design is used for the blade with the least load-bearing capacity, and no noise reduction design is performed for the blade with the largest load-bearing capacity.

[0047] Specifically, Figure 1 Taking the outlet guide vane (OGV) of the fan shown as an example, there are 48 blades in one circle of the fan OGV, and the 48 fan OGV blades are divided into four levels according to the load-bearing load.

[0048] The first-level load A is the two blades at 12 o'clock and 6 o'clock or the closest to 12 o'clock and 6 o'clock positions, which serve as the main fan OGV and provide the main rigidity and load, and the preferred material is TC4 titanium alloy. The second-level load B is the two blades located at 12 o'clock or the closest to 12 o'clock of the first-level load, which are adjacent to the circumferential blades, and provide auxiliary rigidity and load for the first-level load, and the preferred material is TC4 titanium alloy.

[0049] The blades of the fourth-stage load C and the third-stage load D are arranged alternately in the circumferential direction, and the blades close to the second-stage load are the blades of the fourth-stage load, and the blades close to the 6 o'clock position of the first-stage load or the closest to the 6 o'clock position are the blades of the third-stage load. In this way, the third-stage load includes 24 fans OGV arranged at intervals, preferably made of aluminum alloy; the fourth-stage load includes 22 fans OGV arranged at intervals, preferably made of aluminum alloy.

[0050] In this way, the blades are graded according to their load-bearing capacity. Under the premise of clarifying the load-bearing capacity of each level of blades, appropriate materials and structures are selected according to the rigidity and load-bearing capacity of different levels of blades, so that the blade noise reduction design can be carried out under the premise of meeting safety requirements. The first-level load-bearing blades with the largest load-bearing capacity will not be designed for noise reduction because they bear the main load-bearing function. The fourth-level load-bearing blades with the least load-bearing capacity can be appropriately reduced in weight and a hollow noise reduction blade design can be adopted.

[0051] It will be appreciated by those skilled in the art that blade classification includes but is not limited to using Figure 1 The grading method shown is specifically determined according to the actual load-bearing of the blade, and the number of grades is not limited to the four categories mentioned in the above embodiment.

[0052] The blades with the least load-bearing capacity can be Figures 2 to 4BThe lightweight noise reduction blade structure shown includes a blade body 10 , a pair of cover plates 20 , a silencer plate 30 and a pair of honeycomb structures 40 .

[0053] The blade body 10 includes a frame 11 and a hollow cavity 12 located in the frame 11. A pair of cover plates 20 are respectively arranged on both sides of the blade to close the hollow cavity 12 and form a blade pot 13 and a blade back 14 of the blade. The cover plate located on the blade back 14 side is called a blade back cover plate 21, and the cover plate located on the blade pot 13 side is called a blade pot cover plate 22. Figure 3 The hollow cavity 12 occupies the main space of the blade, including the blade root side and the blade tip side, which will greatly achieve the effect of weight reduction.

[0054] The muffler plate 30 is disposed between the blade back cover plate 21 and the blade basin cover plate 22, and is located in the hollow cavity 12. The muffler plate 30 can be made of a resin-based composite material, including but not limited to aramid, polyimide, S2 glass fiber, and the like.

[0055] The sound-absorbing plate 30 may also be made of an elastic material with a certain elasticity, and can be inserted into the middle hollow cavity 12 by being squeezed.

[0056] The honeycomb structure 40 is respectively arranged between the cover plate 10 and the muffler plate 30 to form a blade back honeycomb 41 and a blade basin honeycomb 42. The inner sides of the blade back honeycomb 41 and the blade basin honeycomb 42 are bonded to the middle muffler plate 30 by adhesive film, and the outer sides are bonded to the cover plate 10 by adhesive film.

[0057] The honeycomb structure preferably adopts high bending strength aluminum alloy honeycomb to ensure the overall rigidity, and may also adopt resin-based composite material honeycomb.

[0058] In this way, the blade basin side cover plate, honeycomb, and silencer plate together form the blade basin side silencer chamber, and the blade back side cover plate, honeycomb, and silencer plate together form the blade back side silencer chamber, so that the blades carried by this stage form a double silencer chamber structure on both sides of the blade basin and the blade back, thereby minimizing the fan rear-transmitted noise.

[0059] The honeycomb structure 40 includes a plurality of honeycomb units 400, each of which includes a plurality of honeycombs 401. The honeycomb unit 400 includes a central honeycomb 410 located in the middle and a plurality of annular honeycombs 420 surrounding the outer periphery of the central honeycomb 410.

[0060] It is understood by those skilled in the art that the central cell 410 and the annular cell 420 include but are not limited to: Figure 5A The hexagonal honeycomb structure shown.

[0061] Each honeycomb unit 400 includes a sound-absorbing hole 44 arranged on the cover plate 20, and the sound-absorbing hole 44 on the cover plate corresponds to the middle honeycomb lattice directly above it; and also includes a sound transmission hole 45 arranged on the wall surface of the central honeycomb 410. That is, a "one-way six-way" sound-absorbing design is adopted, and the central honeycomb 410 connected to the outside is connected to the multiple annular honeycombs 420 next to it through multiple door-shaped sound transmission holes 45, such as Figure 5A and 5B As shown. The honeycomb lattice and the sound-absorbing panel can dissipate the incoming sound wave energy as much as possible and as quickly as possible, thereby improving the noise reduction effect.

[0062] The surfaces of the blade basin cover plate 22 and the blade back cover plate 21 are provided with muffler holes 44, which are preferably tapered holes with a cone angle of 45° to absorb sound waves and reduce fan back-transmitted noise. The middle honeycomb of each honeycomb unit 400 "one-through six-reach" honeycomb lattice corresponds to a tapered muffler hole 44.

[0063] The blade basin cover plate 22 and the blade back cover plate 21 are bonded to the honeycomb structure 40 and the frame 11 of the blade body 10 by means of adhesive films.

[0064] The above-mentioned lightweight noise reduction blades use lightweight honeycomb and composite muffler panels instead of aluminum alloy, combined with hollow cavities, to achieve a weight reduction effect. In this way, for the fourth-level load-bearing fan OGV blades with the least load-bearing capacity, the blades are expected to reduce weight by 45% and reduce noise by more than 2db; while no weight reduction design is performed for blades of other load-bearing levels.

[0065] In this way, the lightweight design of the blades is carried out according to the rigidity and load-bearing classification of different blades, which not only ensures the overall safety of the blades, but also realizes the lightweight and noise reduction design. On the premise of meeting the safety requirements, the lightweight and noise reduction blade design is carried out efficiently, solving the contradictions in the traditional design.

[0066] The present application uses specific words to describe the embodiments of the present application. For example, "one embodiment", "an embodiment", and / or "some embodiments" refer to a certain feature, structure or characteristic related to at least one embodiment of the present application. Therefore, it should be emphasized and noted that "one embodiment" or "an embodiment" or "an alternative embodiment" mentioned twice or multiple times in different positions in this specification does not necessarily refer to the same embodiment. In addition, some features, structures or characteristics in one or more embodiments of the present application can be appropriately combined.

[0067] Although the present invention is disclosed as above with preferred embodiments, it is not intended to limit the present invention. Any person skilled in the art may make possible changes and modifications without departing from the spirit and scope of the present invention. Therefore, any modification, equivalent change and modification made to the above embodiments according to the technical essence of the present invention without departing from the content of the technical solution of the present invention shall fall within the protection scope defined by the claims of the present invention.

Claims

1. A blade lightweight noise reduction design method, characterized in that: The steps include: S1. Classifying a circle of blades distributed in the circumferential direction according to the load-bearing weight, and obtaining multiple types of blades according to the different load-bearing weights; S2. Use hollow noise reduction blade design for the blade with the least weight bearing, and do not use noise reduction design for the blade with the most weight bearing.

2. A lightweight noise reduction blade, characterized in that: The method according to claim 1 is used to obtain a type of blade with the least load-bearing capacity, and the blade includes: A blade body, comprising a frame and a hollow cavity located in the frame; A pair of cover plates, respectively disposed on both sides of the blade to close the hollow cavity; a sound-absorbing plate disposed between the pair of cover plates and located in the hollow cavity; and A pair of honeycomb structures are respectively arranged between the cover plate and the muffler plate.

3. The lightweight noise reduction blade according to claim 2, characterized in that: The cover plate is provided with a sound-absorbing hole corresponding to the honeycomb structure.

4. The lightweight noise reduction blade according to claim 3, characterized in that: The muffler hole arranged on the cover plate on the back side of the blade is a conical hole with a cone angle of 45 degrees.

5. The lightweight noise reduction blade according to claim 3, characterized in that: The honeycomb structure includes a plurality of honeycomb units, and each of the honeycomb units includes a central honeycomb located in the middle and an annular honeycomb surrounding the central honeycomb.

6. The lightweight noise reduction blade according to claim 5, characterized in that: Each of the honeycomb units includes a sound-absorbing hole arranged on the cover plate, and a sound-transmitting hole arranged on the wall surface of the central honeycomb, and the sound-transmitting hole is used to connect the central honeycomb and each of the annular honeycombs.

7. The lightweight noise reduction blade according to claim 2, characterized in that: The cover plate is configured to be bonded to the honeycomb structure and the blade body by means of an adhesive film, and the honeycomb structure is configured to be bonded to the muffler plate by means of an adhesive film.

8. The lightweight noise reduction blade according to claim 2, characterized in that: The sound-absorbing plate is made of a resin composite material.

9. The lightweight noise reduction blade according to claim 2, characterized in that: The sound-absorbing plate is made of elastic material.

10. The lightweight noise reduction blade according to claim 2, characterized in that: The honeycomb structure is made of aluminum alloy honeycomb.

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