CN115050347A

CN115050347A - Noise silencer

Info

Publication number: CN115050347A
Application number: CN202210822751.6A
Authority: CN
Inventors: 陈千一; 章珈彬; 江俊; 赵圣宇; 陈鑫; 曹继来
Original assignee: Hefei Hualing Co Ltd; Midea Group Co Ltd; Hefei Midea Refrigerator Co Ltd
Current assignee: Hefei Hualing Co Ltd; Midea Group Co Ltd; Hefei Midea Refrigerator Co Ltd
Priority date: 2022-07-12
Filing date: 2022-07-12
Publication date: 2022-09-13
Also published as: WO2024011964A1

Abstract

The invention discloses a silencer, which comprises: the waveguide tube is provided with a sound wave inlet; the sound absorption tube and the reflection tube are arranged along the tube length direction of the waveguide tube and communicated with the waveguide tube, the sound absorption tube is arranged close to a sound wave inlet of the waveguide tube relative to the reflection tube, the reflection tube and the sound absorption tube are both 1/4 waveguide tubes, and the cross section area of the reflection tube is larger than that of the sound absorption tube. According to the invention, the sound absorption pipe and the reflection pipe which are different in cross section area and are both 1/4 wave pipes are arranged on the wave guide pipe, so that good ventilation and heat dissipation are ensured, good noise reduction effect can be brought, acoustic boundary in the wave guide pipe is unchanged, prejudgment precision of the noise reduction effect is high, and forward design of noise reduction is facilitated. And two 1/4 wave-length tubes are designed through the same frequency point, so that the transmission loss of the target frequency higher than 10dB can be realized, the sound absorption plays a main role, and the sound absorption coefficient is more than 0.9.

Description

Noise silencer

Technical Field

The invention relates to the technical field of silencing equipment, in particular to a silencer.

Background

In the existing noise reduction technology, porous materials such as sound absorption cotton are attached to the wall surface of a ventilation pipeline in the traditional method, and if the ventilation and heat dissipation performance is required to be guaranteed, the thickness of the sound absorption cotton is limited, so that the noise reduction capability is limited. In addition, 1-3dB noise reduction effect can be realized by designing the acoustic metamaterial near the air inlet and the air outlet of the ventilation system. However, for different application scenarios, if the acoustic boundary is complex, forward design cannot be performed through simulation, and the target noise reduction frequency band is not easy to grasp; the magnitude of the noise reduction may also fluctuate due to variations in the size of the vents. In the existing noise reduction technology, the design of resonant cavity on the side wall of the waveguide has been widely used, and the noise reduction effect is generally measured by transmission loss, and the transmission loss is composed of two parts: reflection and sound absorption.

In the existing noise reduction equipment, a single 1/4 wavelength tube is mostly used for noise reduction, a single 1/4 wavelength tube is adopted for noise reduction of a certain frequency point, the cross-sectional area of the 1/4 wavelength tube can be increased to improve transmission loss, but the transmission loss is mainly contributed by reflection, and the reflected sound waves are likely to radiate outwards from other positions, so that the noise reduction is not facilitated.

Disclosure of Invention

The present invention is directed to solving at least one of the problems of the prior art. Therefore, an object of the present invention is to provide a silencer, which can greatly improve the noise reduction effect by matching a waveguide tube with two sound absorbing tubes and two reflecting tubes with different cross-sectional areas.

A muffler according to an embodiment of the present invention includes: the waveguide tube is provided with a sound wave inlet; the sound absorption pipe and the reflection pipe, the sound absorption pipe with the reflection pipe is followed the tube length direction of waveguide pipe arranges, and communicates the waveguide pipe, the sound absorption pipe is relative the reflection pipe is close to the waveguide pipe the sound wave entry is arranged, the reflection pipe with the sound absorption pipe is 1/4 wave length pipes, the cross sectional area of reflection pipe is greater than the cross sectional area of sound absorption pipe.

According to the silencer provided by the embodiment of the invention, the sound absorption pipe and the reflection pipe which are different in cross section area and are 1/4 wave pipes are arranged on the wave guide pipe, so that good ventilation and heat dissipation are ensured, and meanwhile, a better noise reduction effect can be brought. And two 1/4 wave-length tubes are designed through the same frequency point, so that the transmission loss of the target frequency higher than 10dB can be realized, the sound absorption plays a main role, and the sound absorption coefficient is more than 0.9.

In some embodiments of the invention, the sound absorbing tube and the reflection tube are both folded tubes.

In some embodiments of the invention, the folding pipe is bent to form a plurality of pipe parts, the plurality of pipe parts are sequentially connected, an included angle is formed between any two adjacent pipe parts, and the included angle ranges from 0 degree to 90 degrees.

In some embodiments of the invention, any two adjacent tube portions are disposed parallel to and in close proximity to each other.

In some embodiments of the present invention, the number of the pipe portions formed by bending the sound absorption pipe and the reflection pipe is different; or the number of the pipe parts formed by bending the sound absorption pipes and the reflection pipes is the same.

In some embodiments of the present invention, a plurality of the tube portions are arranged side by side and formed with an arrangement plane, which is arranged in a horizontal direction or in a vertical direction.

In some embodiments of the invention, a plurality of the tube portions are arranged side by side and formed with an arrangement plane which is inclined with respect to the horizontal plane.

In some embodiments of the invention, the distance between the sound absorption pipe and the reflection pipe is 50mm to 300 mm.

In some embodiments of the present invention, the cross-sectional area of the sound-absorbing pipe and the reflection pipe is 1.5% to 30% of the cross-sectional area of the waveguide pipe.

In some embodiments of the present invention, a cross-sectional profile of the waveguide, the sound absorption pipe, and the reflection pipe is at least any one of circular, square, and rectangular.

In some embodiments of the present invention, the wall thicknesses of the waveguide tube, the sound absorption tube and the reflection tube are 1-4 mm.

In some embodiments of the present invention, the sound absorbing pipes and the reflection pipes are arranged in plural sets in a pipe length direction of the waveguide pipe, each set including one of the sound absorbing pipes and one of the reflection pipes.

Additional aspects and advantages of the invention will be set forth in part in the description which follows and, in part, will be obvious from the description, or may be learned by practice of the invention.

Drawings

The above and/or additional aspects and advantages of the present invention will become apparent and readily appreciated from the following description of the embodiments, taken in conjunction with the accompanying drawings of which:

FIG. 1 is a schematic view of a muffler in an embodiment of the present invention;

FIG. 2 is a bottom view of a muffler in an embodiment of the present invention;

fig. 3 is a schematic perspective view of a silencer according to an embodiment of the present invention.

Reference numerals:

100. a muffler;

10. a waveguide; 20. a sound absorbing pipe; 30. a reflection tube; 201. a tube portion.

Detailed Description

Reference will now be made in detail to embodiments of the present invention, examples of which are illustrated in the accompanying drawings, wherein like or similar reference numerals refer to the same or similar elements or elements having the same or similar function throughout. The embodiments described below with reference to the accompanying drawings are illustrative only for the purpose of explaining the present invention, and are not to be construed as limiting the present invention.

Referring now to fig. 1-3, a muffler 100 according to an embodiment of the present invention is described. The silencer 100 may be applied to various devices that need to be silenced, for example, the silencer 100 may be applied to a duct machine, and the silencer 100 is connected to an air outlet of the duct machine to realize silencing and noise reduction of the duct machine. For another example, the muffler 100 may also be applied to a compressor compartment of a refrigerator for removing noise generated from a compressor. Of course, this is merely an example, and the silencer 100 may also be applied to other devices requiring noise elimination and noise reduction, which is not described herein again.

As shown in fig. 1 to 3, a muffler 100 according to an embodiment of the present invention includes: waveguide 10, sound absorption tube 20, reflection tube 30.

The waveguide 10 is provided with a sound wave inlet (not shown); the sound absorption tube 20 and the reflection tube 30 are arranged along the tube length direction of the waveguide tube 10 and are communicated with the outer tube wall of the waveguide tube 10, so that the normal heat dissipation effect is not influenced; the sound absorption tube 20 is arranged close to the sound wave inlet of the waveguide tube 10 relative to the reflection tube 30, the reflection tube 30 and the sound absorption tube 20 are both 1/4 waveguide tubes, and the cross-sectional area of the reflection tube 30 is larger than that of the sound absorption tube 20.

It will be appreciated that the waveguide 10 can provide ventilation, heat dissipation, and acoustic path control, and can provide noise reduction in cooperation with the first resonant cavity 20 and the second resonant cavity 30. The cross section area of the sound absorption pipe 20 is relatively small, the reflection coefficient is relatively low, the sound absorption coefficient is relatively high, the sound absorption effect is good, and the sound absorption effect is mainly achieved. The cross section area of the reflection pipe 30 is large, the reflection coefficient is high, the sound absorption coefficient is low, the reflection effect is mainly achieved, and the sound wave reflection effect is good. When the muffler 100 works, sound waves enter from a sound wave inlet of the waveguide tube 10, firstly pass through the sound absorption tube 20, then pass through the reflection tube 30 to be radiated outwards, and through the mutual combination action of the sound absorption tube 20 and the reflection tube 30, the peak value of the sound absorption coefficient can be improved to 0.9636, namely the noise reduction is 14.4dB, the transmissivity is as low as 0.0255, the transmission loss is 15.9dB, the transmission loss is mainly contributed by sound absorption, and more than 96% of sound energy is converted into heat energy in the 1/4 waveguide tube through friction. The reflection tube 30 and the sound absorption tube 20 are both 1/4 wave tubes, and the high-order resonance frequency of the 1/4 wave tube can play a more obvious noise reduction effect within 6400 Hz.

According to the silencer 100 of the embodiment of the invention, the sound absorption pipe 20 and the reflection pipe 30 which are different in cross section area and are 1/4 wave pipes are arranged on the wave guide pipe 10, so that good ventilation and heat dissipation can be ensured, and meanwhile, a good noise reduction effect can be brought. And two 1/4 wave-length tubes are designed through the same frequency point, so that the transmission loss of the target frequency higher than 10dB can be realized, the sound absorption plays a main role, and the sound absorption coefficient is more than 0.9.

As shown in fig. 2 and 3, in some embodiments of the present invention, the sound absorbing pipe 20 and the reflection pipe 30 are both folded pipes. When the target frequency is lower, the lengths required by the sound absorption pipe 20 and the reflection pipe 30 are longer, the whole structure of the silencer 100 is more compact by adopting the design mode of folding pipes for the sound absorption pipe 20 and the reflection pipe 30, the silencer has smaller volume and larger space utilization rate, can adapt to different space structures, and is more flexible to apply and wider in application range.

As shown in fig. 2, in some embodiments of the present invention, the folded tube is bent to form a plurality of tube portions 201, and an included angle is formed between any two tube portions 201, and the included angle ranges from 0 to 90 degrees. The lower the target frequency is, the longer the lengths of the sound absorbing pipe 20 and the reflection pipe 30 are, so that the number of pipe parts 201 formed by bending the folded pipe can be increased, the better sound absorbing and emitting effects are ensured, the overall length of the 1/4-wavelength pipe can be greatly shortened, and the larger space is saved. In the description of the present invention, "a plurality" means two or more unless otherwise specified.

The included angle formed between any two pipe portions 201 may be any one of 0 degree, 10 degrees, 30 degrees, 45 degrees, 60 degrees, 80 degrees, and 90 degrees, but the included angle is not limited to the above example, and may be other values in the range of 0 to 90 degrees, and may be specifically set according to circumstances.

As shown in FIG. 2, in some embodiments of the invention, any two adjacent tubular portions 201 are disposed parallel to and in close proximity to each other. That is to say, two adjacent pipe portions 201 are arranged in parallel and are mutually attached, so that the structure between the plurality of pipe portions 201 can be ensured to be more compact, and the space can be further saved.

As shown in fig. 2, in some embodiments of the present invention, the number of pipe portions 201 formed by bending the sound absorbing pipe 20 and the reflection pipe 30 is different; alternatively, the number of pipe sections 201 formed by bending the sound absorbing pipe 20 and the reflection pipe 30 is the same.

For example, the number of the pipe portions 201 formed by bending the sound absorbing pipe 20 is three, and the number of the pipe portions 201 formed by bending the reflection pipe 30 is two. Alternatively, three pipe sections 201 are formed by bending the sound absorbing pipe 20, and three pipe sections 201 are formed by bending the reflection pipe 30. Here, the number of the pipe portions 201 formed by the sound absorbing pipe 20 and the number of the pipe portions 201 formed by the reflection pipe 30 are only by way of example, and are not limited thereto, and may be other numbers, and are not described again.

Specifically, the total lengths of each group of sound absorbing pipes 20 and reflecting pipes 30 are the same, and the noise reduction target sound frequency sections of the sound absorbing pipes 20 and the reflecting pipes 30 with the same length are the same, so that higher space utilization rate can be realized and the volume of the silencer 100 can be reduced because the pipe diameters of the sound absorbing pipes 20 and the reflecting pipes 30 are different, the length and the number of each bent pipe portion 201 can be the same or different, and the length and the number of the pipe portions 201 do not affect the noise reduction capability.

In some embodiments of the present invention, the plurality of duct parts 201 are arranged side by side and formed with an arrangement plane, which is arranged in a horizontal direction or in a vertical direction.

Specifically, as shown in fig. 2, a plurality of tube portions 201 are arranged side by side on a horizontal plane parallel to the tube length direction of the waveguide 10. Alternatively, the plurality of tube portions 201 are arranged side by side on a vertical plane parallel to the tube length direction of the waveguide 10.

That is, the bending directions of the sound absorbing pipe 20 and the reflection pipe 30 can be specifically set according to the situation, the pipe portions 201 can be located in the vertical plane and the horizontal plane, and the ability of bending the sound absorbing pipe 20 and the reflection pipe 30 in any direction in space provides more possibilities for the design of the silencer 100, and is not limited to that the pipe portions 201 of the sound absorbing pipe 20 and the reflection pipe 30 are arranged in parallel with the pipe wall of the waveguide 10, and more appearance design combinations can be provided according to the different sections of the waveguide 10; meanwhile, the side-by-side design of the pipe portions 201 enables the structure of the whole noise reduction device 100 to be more compact, so that the noise reduction device 100 has a smaller volume and provides a larger space utilization rate, and the noise reduction device 100 can be suitable for more device structures.

In some embodiments of the invention, the plurality of tube sections 201 are arranged side by side and form an arrangement plane that is inclined with respect to the horizontal plane. In other cases, the arrangement plane formed by the plurality of pipe portions 201 may be inclined in consideration of the avoidance requirement, and the effect of making the structure more compact and occupying less space is also achieved.

In some embodiments of the present invention, the distance between the sound-absorbing duct 20 and the reflection duct 30 is 50mm to 300 mm. That is, the distance between the sound absorbing tube 20 and the reflection tube 30 is any one of 50mm, 80mm, 100mm, 150mm, 180mm, 200mm, 250mm, 280mm, and 300mm, or may be any other value within a range of 50mm to 300mm, and is not described herein again.

Specifically, the distance between the sound absorption tube 20 and the reflection tube 30 is 50 mm-300 mm, which does not affect the sound frequency band of the targeted noise reduction; when the distance between the sound absorption tube 20 and the reflection tube 30 exceeds the range, sound is transmitted out of the wave tube 10, so that the noise reduction effect of the silencer 100 is reduced; another important function of the distance range between the sound absorbing pipe 20 and the reflection pipe 30 is to provide a bending space for the pipe portions 201 of the sound absorbing pipe 20 and the reflection pipe 30 having a bending design, increase the space utilization rate, and ensure that each pipe portion 201 has a proper bending position.

As shown in fig. 2, in some embodiments of the present invention, the cross-sectional areas of the sound-absorbing pipe 20 and the reflection pipe 30 are 1.5% to 30% of the cross-sectional area of the waveguide 10.

It can be understood that, for a certain area of the wavelength tube 10, as the cross-sectional area of the 1/4 wavelength tube increases, the sound absorption coefficient increases first and then decreases, the maximum value is 0.5, the reflection coefficient increases continuously, and the transmission loss increases continuously; therefore, the pipe diameter of the sound absorption pipe 20 should be the pipe diameter size when the sound absorption coefficient is 0.5, the pipe diameter of the reflection pipe 30 should be the pipe diameter size when the transmittance of the 1/4 wavelength tube is lowest and the reflectivity is higher, and each group of silencers formed at this time has the best noise reduction capability; the optimal pipe diameter ranges of the sound absorption pipe 20 and the reflection pipe 30 are that the cross section areas of the sound absorption pipe 20 and the reflection pipe 30 are 1.5% -30% of the cross section area of the waveguide 10, the cross section areas of the sound absorption pipe 20 and the reflection pipe 30 can be any one of 1.5%, 2%, 3%, 5%, 10%, 15%, 20%, 30% of the cross section area of the waveguide 10, and can be other values within the ranges, which are not described in detail here, and the final value is based on the design requirement of the waveguide pipe diameter.

In some embodiments of the present invention, the cross-sectional profiles of the waveguide 10, the sound-absorbing duct 20, and the reflection duct 30 are at least any one of circular, square, and rectangular. Specifically, the sectional shape of the silencer 100 does not affect the noise reduction capability of the silencer 100, and thus, the differently shaped sectional designs provide more design possibilities for the silencer 100, and thus, the cross-sectional profiles of the waveguide 10, the sound-absorbing pipe 20, and the reflection pipe 30 may be circular, may be configured as a square, or may be configured as a rectangle. Accordingly, the aperture shapes of the waveguide tube 10, the sound absorption tube 20, and the reflection tube 30 are the same as the shape of the pipe cross-sectional profile.

Of course, the cross-sectional profiles of the waveguide 10, the sound absorption tube 20 and the reflection tube 3 may be configured in other shapes, for example, regular hexagon, triangle, etc., which will not be described herein.

In some embodiments of the present invention, the wall thicknesses of the waveguide 10, the sound absorbing pipe 20 and the reflection pipe 30 are 1 to 4 mm. That is, the wall thickness of the waveguide 10, the sound absorption tube 20, and the reflection tube 30 may be any one of 1mm, 1.2mm, 1.5mm, 1.8mm, 2mm, 2.5mm, 3.0mm, 3.5mm, and 4.0mm, or may be other values, which is not described in detail here.

In some embodiments of the present invention, the sound absorbing pipes 20 and the reflection pipes 30 are arranged in a plurality of groups in the pipe length direction of the waveguide 10, each group including one sound absorbing pipe 20 and one reflection pipe 30.

That is to say, the sound absorbing tube 20 and the reflection tube 30 are made of 1/4 wavelength probes made of acoustic metamaterial, the acoustic metamaterial has a very high sound absorption coefficient and a very low transmittance, and can achieve a targeted sound absorption and noise reduction effect on one sound frequency band, the combination of the sound absorbing tube 20 and the reflection tube 30 can achieve a targeted noise reduction on a plurality of sound frequency bands within a range, and in addition, the 1/4 wavelength tube has a plurality of high-order resonance frequency points within 6400Hz, and can achieve a good noise reduction effect within 6400 Hz.

One embodiment of the muffler 100 of the present invention will be described with reference to the accompanying drawings.

As shown in fig. 1 and 2, the muffler 100 includes: waveguide tube 10, sound absorption tube 20, reflection tube 30.

The waveguide 10 is provided with an acoustic wave inlet.

The sound absorption tube 20 and the reflection tube 30 are arranged along the tube length direction of the waveguide tube 10 and are communicated with the outer tube wall of the waveguide tube 10, the sound absorption tube 20 is arranged close to the air inlet of the waveguide tube 10 relative to the reflection tube 30, the reflection tube 30 and the sound absorption tube 20 are both 1/4 wave tubes, and the cross-sectional area of the reflection tube 30 is larger than that of the sound absorption tube 20.

The sound absorbing pipe 20 and the reflecting pipe 30 are both folded pipes.

The sound absorbing pipe 20 is bent to form three pipe portions 201, the reflection pipe 30 is bent to form two pipe portions 201, and any two pipe portions 201 are parallel to each other and are arranged in close proximity to each other.

The three pipe portions 201 of the sound absorbing pipe 20 and the two pipe portions 201 of the reflection pipe 30 are arranged side by side on a horizontal plane parallel to the pipe length direction of the waveguide 10.

The distance between the sound-absorbing duct 20 and the reflection duct 30 is 50 mm.

The cross-sectional area of the sound-absorbing pipe 20 was 1.5% of the cross-sectional area of the waveguide 10, and the cross-sectional area of the sound-absorbing pipe 20 was 3.5% of the cross-sectional area of the waveguide 10.

The cross-sectional profiles of the waveguide tube 10, the sound-absorbing tube 20, and the reflection tube 30 are circular.

The wall thicknesses of the waveguide tube 10, the sound absorbing tube 20, and the reflection tube 30 are 2 mm.

Other constructions and operations of the muffler 100 according to embodiments of the present invention are known to those of ordinary skill in the art and will not be described in detail herein.

In describing the present invention, it is to be understood that the terms "central," "longitudinal," "transverse," "length," "width," "thickness," "upper," "lower," "front," "rear," "left," "right," "vertical," "horizontal," "top," "bottom," "inner," "outer," "clockwise," "counterclockwise," "axial," "radial," "circumferential," and the like are used in an orientation or positional relationship indicated in the drawings for convenience and simplicity of description only, and are not intended to indicate or imply that the referenced device or element must have a particular orientation, be constructed and operated in a particular orientation, and are therefore not to be considered limiting.

In the description of the specification, reference to the description of "some embodiments," "optionally," "further" or "some examples" or the like is intended to mean that a particular feature, structure, material, or characteristic described in connection with the embodiment or example is included in at least one embodiment or example of the invention. In this specification, the schematic representations of the terms used above do not necessarily refer to the same embodiment or example. Furthermore, the particular features, structures, materials, or characteristics described may be combined in any suitable manner in any one or more embodiments or examples.

While embodiments of the invention have been shown and described, it will be understood by those of ordinary skill in the art that: various changes, modifications, substitutions and alterations can be made to the embodiments without departing from the principles and spirit of the invention, the scope of which is defined by the claims and their equivalents.

Claims

1. A muffler, comprising:

the waveguide tube is provided with a sound wave inlet;

the sound absorption pipe and the reflection pipe, the sound absorption pipe with the reflection pipe is followed the tube length direction of waveguide pipe arranges, and communicates the waveguide pipe, the sound absorption pipe is relative the reflection pipe is close to the waveguide pipe the sound wave entry is arranged, the reflection pipe with the sound absorption pipe is 1/4 wave length pipes, the cross sectional area of reflection pipe is greater than the cross sectional area of sound absorption pipe.

2. The muffler of claim 1, wherein the sound absorbing pipe and the reflection pipe are each folded pipes.

3. The silencer of claim 2, wherein the folded pipe is bent to form a plurality of pipe portions, the plurality of pipe portions are sequentially connected, an included angle is formed between any two adjacent pipe portions, and the included angle ranges from 0 degree to 90 degrees.

4. The muffler of claim 3, wherein any two adjacent pipe portions are disposed in parallel and in close proximity to each other.

5. The muffler according to claim 3, wherein the number of the pipe portions formed by bending the sound absorbing pipe and the reflection pipe is different; or the number of the pipe parts formed by bending the sound absorption pipes and the reflection pipes is the same.

6. The silencer according to claim 3, wherein a plurality of the pipe portions are arranged side by side and formed with an arrangement plane that is arranged in a horizontal direction or in a vertical direction.

7. The silencer of claim 3, wherein a plurality of said pipe portions are arranged side by side and formed with an arrangement plane that is inclined with respect to a horizontal plane.

8. The muffler of claim 1, wherein a distance between the sound absorbing pipe and the reflection pipe is 50mm to 300 mm.

9. The silencer of claim 1, wherein the cross-sectional areas of the sound absorbing duct and the reflection duct are 1.5% to 30% of the cross-sectional area of the waveguide.

10. The silencer of claim 1, wherein a cross-sectional profile of the waveguide, the sound absorbing pipe, and the reflection pipe is at least any one of circular, square, and rectangular.

11. The silencer of claim 1, wherein the waveguide, the sound absorbing pipe, and the reflection pipe have a pipe wall thickness of 1-4 mm.

12. The silencer of claim 1, wherein the sound absorbing pipes and the reflection pipes are arranged in plural sets in a pipe length direction of the waveguide, each set including one of the sound absorbing pipes and one of the reflection pipes.