Silencer

Abstract

To reduce radiated sound due to vibration of a sound absorption splitter.SOLUTION: A silencer includes a plurality of sound absorption splitters which are arranged along a first direction in which a sound wave from a sound source is propagated and are aligned in a second direction crossing the first direction. At least one sound absorption splitter includes a sound source side portion and a tip side portion, which are aligned in the first direction. The dimension of the sound source side portion in the second direction is the same or almost the same as the dimension of the tip side portion in the second direction. The sound source side portion and the tip side portion are arranged with an interval in the first direction. Sound absorption materials are provided in the inside of the sound source side portion and the inside of the tip side portion. In the sound source side portion and the tip side portion, pores are formed on top faces being ends in a third direction orthogonal to the first direction and the second direction.SELECTED DRAWING: Figure 5

Description

[Technical field]

[0001] The present disclosure relates to a silencer. [Background technology]

[0002] In the ducts of gas turbines, etc., silencers are arranged to reduce sound waves propagating from the gas turbine, which is a sound source. As a silencer, for example, a configuration in which multiple sound-absorbing splitters are arranged is known (for example, see Patent Documents 1 and 2, etc.). [Prior art documents] [Patent documents]

[0003] [Patent Document 1] Special Publication No. 2017-531143 [Patent Document 2] JP 2017-062465 A Summary of the Invention [Problem to be solved by the invention]

[0004] In the above-mentioned silencer, it is required to reduce the radiated sound caused by the vibration of the sound-absorbing splitter.

[0005] The present disclosure has been made in consideration of the above, and has an object to provide a silencer capable of reducing radiated sound caused by vibration of a sound-absorbing splitter. [Means for solving the problem]

[0006] The silencer of the present disclosure has a plurality of sound-absorbing splitters arranged along a first direction in which sound waves from a sound source propagate and aligned in a second direction intersecting the first direction, at least one of the sound-absorbing splitters has a sound-source-side portion and a tip-side portion aligned in the first direction, the dimension of the sound-source-side portion in the second direction is the same or approximately the same as the dimension of the tip-side portion in the second direction, and the sound-source-side portion and the tip-side portion are arranged with a gap in the first direction so that vibrations propagating from the sound-source-side portion to the tip-side portion are suppressed when the sound-source-side portion is vibrated by sound waves from the sound source. Effect of the Invention

[0007] According to the present disclosure, it is possible to reduce radiated sound caused by vibration of the sound-absorbing splitter. [Brief description of the drawings]

[0008] [Figure 1] FIG. 1 is a perspective view showing an example of a silencer according to the present embodiment. [Diagram 2] FIG. 2 is a perspective view that illustrates a configuration of a silencer according to a modified example. [Diagram 3] FIG. 3 is a perspective view that illustrates a configuration of a silencer according to a modified example. [Figure 4] FIG. 4 is a perspective view that illustrates a configuration of a silencer according to a modified example. [Diagram 5] FIG. 5 is a perspective view that illustrates a configuration of a silencer according to a modified example. [Figure 6] FIG. 6 is a view taken along the line AA′ in FIG. [Figure 7] FIG. 7 is a perspective view that illustrates a configuration of a silencer according to a modified example. [Figure 8] FIG. 8 is a perspective view that illustrates a configuration of a silencer according to a modified example. [Figure 9] FIG. 9 is a perspective view that illustrates a configuration of a silencer according to a modified example. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0009] Hereinafter, an embodiment of a silencer according to the present disclosure will be described with reference to the drawings. Note that the present invention is not limited to this embodiment. In addition, the components in the following embodiments include those that are replaceable and easy for a person skilled in the art, or those that are substantially the same.

[0010] Fig. 1 is a perspective view showing an example of a silencer 100 according to the present embodiment. The silencer 100 shown in Fig. 1 is used to reduce sound waves from a sound source. In the present embodiment, a case in which the silencer 100 is disposed at an intake port 50a of a duct 50 of a gas turbine will be described as an example.

[0011] As shown in FIG. 1, the silencer 100 has a plurality of sound-absorbing splitters 10. The plurality of sound-absorbing splitters 10 are arranged along a first direction D1 in which sound waves propagate, and are arranged in a state of being spaced apart in a second direction D2 perpendicular to the first direction D1. Hereinafter, when describing the direction of the sound-absorbing splitter 10, the rear side in which sound waves travel in the first direction D1 is referred to as the sound source side, and the front side in which sound waves travel is referred to as the tip side. In this embodiment, air sucked from the intake port 50a flows toward the gas turbine side. That is, the propagation direction of sound waves from the sound source and the flow direction of air are opposite to each other. In this configuration, the gas turbine, which is the sound source, is arranged downstream of the silencer 100 in the air flow direction.

[0012] Each sound-absorbing splitter 10 has a sound source side portion 11 and a tip side portion 12. The sound source side portion 11 is disposed on the sound source side in the first direction D1. The sound source side portion 11 is formed of a metal such as aluminum, and is hollow inside. The sound source side portion 11 may be provided with a sound absorbing material on the surface or inside.

[0013] The tip side portion 12 is disposed on the tip side in the first direction D1. The tip side portion 12 is formed of a metal such as aluminum, and is hollow inside. The tip side portion 12 may be provided with a sound absorbing material on the surface or inside. The tip side portion 12 is provided with a straightening plate 12r (see FIG. 7) that is curved so as to be convex toward the tip side in the first direction D1. The straightening plate 12r is disposed on the upstream side in the direction in which the air flows.

[0014] When the silencer 100 is disposed at the intake port 50a of the duct 50, the tip side portion 12 is disposed on the intake port 50a side of the duct 50, and the sound source side portion 11 is disposed on the inner side of the duct 50 (gas turbine side).

[0015] In each sound-absorbing splitter 10, the dimension of the sound source side portion 11 in the second direction D2 is the same or approximately the same as the dimension of the tip side portion 12 in the second direction D2. The sound source side portion 11 and the tip side portion 12 are arranged separated by a gap 13 in the first direction D1 so that vibrations propagating from the sound source side portion 11 to the tip side portion 12 are suppressed when the sound source side portion 11 is vibrated by sound waves from the sound source.

[0016] 1 absorbs sound waves propagating from a gas turbine, which is a sound source, through a duct 50, thereby reducing the sound pressure level. The silencer 100 of this embodiment absorbs sound waves at the intake port 50a of the duct 50 so as to reduce the sound pressure level by, for example, 30 dB or more, and in some cases, 40 dB or more.

[0017] The sound waves passing through the silencer 100 include two types of sound waves: direct sound waves that propagate through the air from the sound source and are partially absorbed by the silencer 100, and radiated sound (secondary solid sound) sound waves that are generated when the duct 50 and each sound-absorbing splitter 10 are excited and vibrated by the sound waves from the sound source, and the vibrations are radiated from the intake port 50a side of the duct 50.

[0018] The silencer 100, which exhibits a large sound absorbing performance such as reducing the sound pressure level by 30 dB or more as in this embodiment, is used when the sound pressure level of the sound wave from the sound source itself is large, and the length in the first direction D1 tends to be long. In such a case, the sound radiated from the sound absorbing splitter 10 becomes too large to be ignored.

[0019] The silencer 100 of this embodiment has a configuration in which the sound-absorbing splitter 10 has a sound source side portion 11 and a tip side portion 12, and the sound source side portion 11 and the tip side portion 12 are separated in the first direction D1 by a gap 13. When the silencer 100 of this embodiment is used, the sound source side portion 11 is excited and vibrated by sound waves from the sound source, but the vibration of the sound source side portion 11 is attenuated by the gap 13, so that the propagation of the vibration to the tip side portion 12 is suppressed. Therefore, the radiated sound contained in the sound waves that have passed through the silencer 100 is reduced. In addition, since the dimension of the sound source side portion 11 in the second direction is the same or almost the same as the dimension of the tip side portion 12 in the second direction, the desired sound absorption characteristics are ensured when absorbing direct sound.

[0020] In each sound-absorbing splitter 10, the position in the first direction D1 where the gap 13 is provided can be set as appropriate. In the example shown in FIG. 1, the gap 13 is provided on the tip side of the sound-absorbing splitter 10 from the center in the first direction D1. With this configuration, vibrations from the sound source side portion 11 can be appropriately attenuated. Furthermore, the dimension of the gap 13 in the first direction D1 can also be set as appropriate. By reducing the dimension of the gap 13 in the first direction D1, the overall dimension of the silencer 100 in the first direction can be reduced.

[0021] As described above, the silencer 100 of this embodiment has a plurality of sound-absorbing splitters 10 arranged along a first direction D1 in which sound waves from a sound source propagate, and aligned in a second direction D2 that intersects the first direction D1, and at least one sound-absorbing splitter 10 has a sound source side portion 11 and a tip side portion 12 aligned in the first direction D1, the dimension of the sound source side portion 11 in the second direction is identical or approximately identical to the dimension of the tip side portion 12 in the second direction D2, and the sound source side portion 11 and the tip side portion 12 are arranged with a gap 13 in the first direction so that when the sound source side portion 11 is vibrated by sound waves from the sound source, vibrations propagating from the sound source side portion 11 to the tip side portion 12 are suppressed.

[0022] Therefore, when the sound source side portion 11 is excited to vibrate by sound waves from the sound source, the vibration of the sound source side portion 11 is attenuated by the gap 13, so that the propagation of the vibration to the tip side portion 12 can be suppressed. This makes it possible to reduce radiated sound contained in sound waves that have passed through the silencer 100. In addition, since the dimension in the second direction of the sound source side portion 11 is the same or nearly the same as the dimension in the second direction of the tip side portion 12, it is possible to ensure the desired sound absorption characteristics when absorbing direct sound.

[0023] In the silencer 100 according to this embodiment, the multiple sound-absorbing splitters 10 are disposed at the intake port 50a of the duct 50 connected to the gas turbine. This configuration can reduce the sound waves of the direct sound from the gas turbine and the sound waves of the secondary solid sound caused by the acoustic excitation of the duct 50 and the sound-absorbing splitters 10 due to the direct sound.

[0024] In the present embodiment, a configuration in which each of the multiple sound-absorbing splitters 10 has a sound source side portion 11 and a tip side portion 12 separated by a gap 13 in the first direction D1 has been described as an example, but the present invention is not limited to this. It is sufficient that at least one of the multiple sound-absorbing splitters 10 has a sound source side portion 11 and a tip side portion 12 separated by a gap 13 in the first direction D1.

[0025] Fig. 2 is a perspective view showing a schematic configuration of a silencer 100A according to a modified example. In the silencer 100A shown in Fig. 2, the sound-absorbing splitter 10A has a sound source side portion 11 and a tip side portion 12 connected via an elastic body 14. In this configuration, the propagation of vibration from the sound source side portion 11 to the tip side portion 12 can be more efficiently suppressed.

[0026] Fig. 3 is a perspective view showing a schematic configuration of a silencer 100B according to a modified example. In the silencer 100B shown in Fig. 3, the sound-absorbing splitter 10B has a sound source side portion 11 and a tip side portion 12 connected via an elastic body 14. The tip side portion 12 is elastically supported on an external structure via an elastic body 15. An example of the external structure is the inner wall of a duct 50. With this configuration, the propagation of vibration from the sound source side portion 11 to the tip side portion 12 can be more efficiently suppressed, and the vibration of the tip side portion 12 can be suppressed.

[0027] Fig. 4 is a perspective view showing a schematic configuration of a silencer 100C according to a modified example. In the silencer 100C shown in Fig. 4, the sound-absorbing splitter 10C has a sound source side portion 11 and a tip side portion 12 connected via an expansion joint 16 or a leaf spring 17. In this configuration, the propagation of vibration from the sound source side portion 11 to the tip side portion 12 can be more efficiently suppressed. Note that the silencer 100C may have a configuration in which the sound source side portion 11 and the tip side portion 12 are connected via an expansion joint 16 or a leaf spring 17 in at least one of the multiple sound-absorbing splitters 10C.

[0028] Fig. 5 is a perspective view showing a schematic configuration of a silencer 100D according to a modified example. In the silencer 100D shown in Fig. 5, the sound-absorbing splitter 10D has a sound source side portion 11D and a tip side portion 12D, and the sound-absorbing processed portions 18 are provided on the upper surfaces 11u and 12u, which are ends of the sound source side portion 11D and the tip side portion 12D in the third direction D3 perpendicular to the first direction D1 and the second direction D2, respectively. The sound-absorbing processed portions 18 are, for example, holes formed on the upper surfaces 11u and 12u. The sound-absorbing processed portions 18 may be sound-absorbing materials or the like.

[0029] Fig. 6 is a view taken along the line AA' in Fig. 5. As shown in Fig. 6, the sound absorbing portion 18 is provided on the upper surface 11u of the sound source portion 11D and the upper surface 12u of the tip portion 12D, so that sound waves passing between the upper surfaces 11u, 12u and the ceiling portion 50b of the duct 50 can be efficiently absorbed. In this configuration, a sound absorbing material or the like may be provided on the ceiling portion 50b. Also, a configuration similar to the sound absorbing portion 18 may be provided on the opposing surfaces 11p, 12p of the sound source portion 11D and the tip portion 12D.

[0030] Fig. 7 is a perspective view showing a silencer 100E according to a modified example. In the silencer 100E shown in Fig. 7, the sound-absorbing splitter 10E has a tip portion 12E filled with a filler 19 such as a sound-absorbing material such as urethane or a vibration-damping material such as mortar or an iron plate.

[0031] In the example shown in FIG. 7, the filler 19 is disposed inside the straightening plate 12r, but this is not limited thereto, and the filler 19 may be disposed in the main body portion 12h of the tip side portion 12E.

[0032] When the filler 19 is a sound absorbing material, acoustic resonance in the tip portion 12E can be suppressed, and the generation of radiated sound can be suppressed. When the filler 19 is a vibration damping material, vibration in the tip portion 12E can be more reliably suppressed.

[0033] Fig. 8 is a perspective view showing a silencer 100F according to a modified example. In the silencer 100F shown in Fig. 8, the inside of the straightening plate 12r of the tip side portion 12F of the sound absorbing splitter 10F is hollow and has a lower pressure than the outside. In this configuration, the inside of the straightening plate 12r is made low pressure, so that vibrations in the straightening plate 12r can be suppressed.

[0034] FIG. 9 is a perspective view showing a configuration of a silencer 100G according to a modified example. In the silencer 100G shown in FIG. 9, the sound-absorbing splitter 10G has acoustic resonance devices 20 and 21 that open in the second direction D2 arranged between the sound source side portion 11 and the tip side portion 12. The acoustic resonance device 20 has a rectangular cylindrical shape, and openings 20a and 20b are formed on both sides in the second direction D2. The acoustic resonance device 21 has a configuration similar to that of a resonator, for example, and has a hollow portion 21a that resonates sound and an absorbing portion 21b that absorbs sound, and an opening 21c is provided at the end of the absorbing portion 21b. The acoustic resonance devices 20 and 21 are supported in a vibration-proof manner by, for example, an elastic member or the like. The acoustic resonance devices 20 and 21 may be arranged inside at least one of the sound source side portion 11 and the tip side portion 12. With this configuration, the propagation of vibration from the sound source side portion 11 to the tip side portion 12 can be more reliably suppressed.

[0035] The technical scope of the present invention is not limited to the above-described embodiment, and appropriate modifications can be made without departing from the spirit of the present invention. For example, in the above-described embodiment, a gas turbine is used as an example of a mechanical device that is a sound source, but the present invention is not limited to this. The mechanical device that is a sound source may be another device, such as an exhaust fan.

[0036] In the above embodiment, the silencer (100, 100A, 100B, 100C, 100D, 100E, 100F, 100G) is disposed at the intake port 50a of the duct 50 connected to the machine (gas turbine), but the present invention is not limited thereto. The silencer may be disposed at the exhaust port of the duct connected to the machine. That is, the silencer can be disposed at either the intake port or the exhaust port, as long as the opening of the duct connected to the machine. When the silencer is disposed at the exhaust port of the duct, the direction of air flow is from the machine side to the exhaust port side. Therefore, the machine, which is the sound source, is disposed upstream of the silencer in the direction of air flow. In this configuration, the straightening plate may be disposed at the rear end (rear end of the sound source side portion) of the sound-absorbing splitter in the first direction D1 in which the sound waves propagate. [Explanation of symbols]

[0037] 10,10A,10B,10C,10D,10E,10F,10G Sound absorbing splitter 11,11D Sound source side part 11p,12p Opposite side 11u,12u top surface 12,12D,12E,12F Tip side part 12r rectifier plate 13 intervals 14,15 Elastic bodies 16 Expansion joint 17 Leaf spring 18 Sound absorbing section (sound absorbing hole) 19 Filling 20,21 Acoustic Resonance Devices 20a,20b,21a opening 50 Duct 50a Intake 50b Ceiling section 100, 100A, 100B, 100C, 100D, 100E, 100F, 100G silencer D1 1st direction D2 2nd direction D3 Third direction

Claims

1. The sound absorbing splitter is disposed along a first direction in which sound waves from a sound source propagate, and is aligned in a second direction intersecting the first direction; At least one of the sound absorbing splitters has a sound source side portion and a tip side portion aligned in the first direction, a dimension of the sound source side portion in the second direction is the same as or substantially the same as a dimension of the tip side portion in the second direction, and the sound source side portion and the tip side portion are arranged with a gap therebetween in the first direction, A sound absorbing material is provided inside the sound source side portion and inside the tip side portion, The sound source side portion and the tip side portion have holes formed on their upper surfaces, which are ends in a third direction perpendicular to the first direction and the second direction. Silencer.

2. A plurality of the sound absorbing splitters are disposed inside a duct connected to a mechanical device that is the sound source, The hole is disposed so as to face the ceiling of the duct.

2. The silencer of claim 1.

3. The holes are arranged in a plurality of positions in the first direction and in a plurality of positions in the second direction.

2. The silencer of claim 1.

4. The holes are arranged in a row at an equal pitch in the first direction, and a plurality of rows are provided in the second direction. Between the rows adjacent to each other in the second direction, the positions of the holes are shifted by half a pitch in the first direction. The silencer according to claim 3.

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