CN117711363A - Dissipation enhanced ventilated muffler for transformer noise reduction - Google Patents

Abstract

The utility model discloses a dissipation reinforcing's ventilation formula silencer, but ventilation pipe is hollow circular channel, and the baffle is located in the ventilation pipe, the baffle includes the ring and a plurality of cuboid that outwards radiate from the ring outer wall and extend of circular channel co-axial, and the cuboid is along ventilation pipe's radius connection ring outside and ventilation pipe inboard, and at least one sound absorption unit encircles the ventilation pipe outside, sound absorption unit includes the neck and connects the cavity of neck, the opening intercommunication of neck ventilation pipe just is located between two adjacent cuboids, but ventilation formula silencer transmission loss peak frequency is showing and is reducing silencer size.

Description

Dissipation enhanced ventilated muffler for transformer noise reduction

Technical Field

The invention relates to the technical field of voltage noise control, in particular to a ventilated muffler with enhanced dissipation.

Background

Noise problems are important issues of social concern, and the installation of sound absorbing devices in the propagation path is an important means of controlling noise. In some situations where ventilation is required, ventilation ducts must be left, through which noise can propagate. In order to control noise while ensuring ventilation, a muffler is often added to the ventilation duct. At present, a silencing structure based on a local resonance principle is commonly used, such as a Helmholtz resonance unit and a Fabry-Perot resonance unit, and the structure can control low-frequency noise in a relatively small size and realize efficient noise control on a reasonable structural size. However, as the frequency of the target noise decreases, the required cell size gradually increases. In addition, noise in most scenarios is multi-frequency or wideband, requiring different units in series or parallel to achieve multi-frequency noise control. This causes the overall size of the muffler to be excessively large, thereby causing problems such as inconvenience in installation, reduction in ventilation efficiency, and the like. Therefore, it is a difficulty to realize noise control of a low frequency broadband in a small space.

In the prior art, the space utilization rate is increased by folding, coiling and the like; for Helmholtz resonating structures, the neck may also be embedded into the cavity; such an approach, while capable of somewhat reducing the overall size of the muffler, does not reduce, or even slightly increases, the space required for critical components. In addition, these methods also complicate the structure and make it difficult to process.

The information disclosed in the background section is only for enhancement of understanding of the background of the invention and therefore may contain information that does not form the prior art that is already known to a person of ordinary skill in the art.

Disclosure of Invention

In order to overcome the defects or shortcomings of the prior art, the ventilated muffler with enhanced dissipation is provided, the dissipation of the resonance unit is enhanced by introducing the partition plate at the opening of the neck, and better low-frequency sound absorption effect is realized under the condition of hardly increasing the volume. The dissipation enhanced muffler provided by the invention has a simple structure and is easy to process.

The aim of the invention is achieved by the following technical scheme.

A dissipation enhanced ventilated muffler includes,

a ventilation duct, which is a hollow circular channel,

the baffle plate is arranged in the ventilating duct and comprises a circular ring which is concentric with the circular channel and a plurality of cuboids which radiate outwards from the outer wall of the circular ring, the cuboids are connected with the outer side of the circular ring and the inner side of the ventilating duct along the radius of the ventilating duct,

the sound absorption unit surrounds the outer side of the ventilating duct, the sound absorption unit comprises a neck and a cavity connected with the neck, and an opening of the neck is communicated with the ventilating duct and located between two adjacent cuboids.

In the dissipation enhanced ventilated muffler, the neck and the cavity form a Helmholtz resonant cavity.

In the dissipation enhanced ventilated muffler, the neck is embedded in the cavity and is positioned in the middle of the cavity.

In the dissipation enhanced ventilated muffler, the neck is a cylindrical structure recessed in the cavity.

In the dissipation enhanced ventilated muffler, the cylinder structure is communicated with the ventilating duct and the cavity.

In the dissipation enhanced ventilated muffler, the expansion angle T of the cavity is 30-163.7 degrees, the radius Ra of the neck is 22-29mm, and the height La of the neck is 25-69.5mm.

In the dissipation enhanced ventilated muffler, the radius Rc1 of the inner ring of the cavity is 124.5mm, the radius Rc2 of the outer ring of the cavity is 200mm, the total thickness Dc of the cavity is 66.5mm-128.5mm, the wall thickness of the inner side and the outer side of the cavity is 0.5mm, and the wall thickness of the neck is 1mm.

In the ventilated muffler with enhanced dissipation, the sound absorption peak frequency of the ventilated muffler is consistent with the frequency of the noise of the transformer.

In the dissipation enhanced ventilated muffler, the sound absorption frequency of the sound absorption unit is 100Hz and the frequency multiplication thereof.

In the dissipation enhanced ventilated muffler, a plurality of sound absorption units are formed into an annular structure around the outer side of the ventilating duct.

Compared with the prior art, the invention has the beneficial effects that:

according to the invention, the baffle plate is introduced into the ventilating duct, so that the sound absorption effect of the sound absorption unit is enhanced on the premise of hardly reducing the ventilating effect. The neck part of the Helmholtz resonance structure is embedded into the cavity, so that the whole structure is regular and the space utilization rate is increased; the invention has reasonable scheme, simple structure and easy realization.

The description is merely an overview of the technical solutions of the present invention, in order to make the technical means of the present invention more clearly apparent to those skilled in the art, and in order to make the description of the present invention and other objects, features and advantages of the present invention more obvious, the following description of the specific embodiments of the present invention will be exemplified.

Drawings

Various other advantages and benefits of the present invention will become apparent to those of ordinary skill in the art upon reading the following detailed description of the preferred embodiments. The drawings are only for purposes of illustrating the preferred embodiments and are not to be construed as limiting the invention. It is evident that the figures described below are only some embodiments of the invention, from which other figures can be obtained without inventive effort for a person skilled in the art. Also, like reference numerals are used to designate like parts throughout the figures.

In the drawings:

FIG. 1 is an isometric view of a dissipation enhanced ventilated muffler provided in accordance with one embodiment of the present invention;

FIG. 2 is a schematic diagram showing a front cross-sectional structure of a dissipation enhanced ventilated muffler according to an embodiment of the present invention;

FIG. 3 is a front cross-sectional view and a left side schematic view of a sound absorbing unit of a dissipation enhanced ventilated muffler according to one embodiment of the present invention;

FIG. 4 is a schematic diagram of the transmission loss of a dissipation enhanced ventilated muffler provided by one embodiment of the present invention;

fig. 5 is a transmission loss schematic of a muffler without a baffle.

The invention is further explained below with reference to the drawings and examples.

Detailed Description

Specific embodiments of the present invention will be described in more detail below with reference to the accompanying drawings. While specific embodiments of the invention are shown in the drawings, it should be understood that the invention may be embodied in various forms and should not be limited to the embodiments set forth herein. Rather, these embodiments are provided so that this disclosure will be thorough and complete, and will fully convey the scope of the invention to those skilled in the art.

It should be noted that certain terms are used throughout the description and claims to refer to particular components. Those of skill in the art will understand that a person may refer to the same component by different names. The description and claims do not identify differences in terms of components, but rather differences in terms of the functionality of the components. As used throughout the specification and claims, the terms "include" and "comprise" are used in an open-ended fashion, and thus should be interpreted to mean "include, but not limited to. The description hereinafter sets forth a preferred embodiment for practicing the invention, but is not intended to limit the scope of the invention, as the description proceeds with reference to the general principles of the description. The scope of the invention is defined by the appended claims.

For the purpose of facilitating an understanding of the embodiments of the invention, reference will now be made to the drawings of several embodiments illustrated in the drawings, and the accompanying drawings are not to be taken as limiting the embodiments of the invention.

For better understanding, as shown in fig. 1-5, a dissipation enhanced ventilated muffler includes,

a ventilation duct 1, which is a hollow circular passage,

a partition plate 2 provided in the ventilation duct 1, the partition plate 2 including a circular ring 4 concentric with the circular passage and a plurality of rectangular solids 5 extending radially outward from an outer wall of the circular ring 4, the rectangular solids 5 connecting an outer side of the circular ring 4 and an inner side of the ventilation duct 1 along a radius of the ventilation duct 1,

at least one sound absorbing unit 3, it surrounds the air pipe 1 outside, the sound absorbing unit 3 includes neck 6 and connects the cavity 7 of neck 6, the opening of neck 6 communicates air pipe 1 and is located between two adjacent cuboid 5.

In the preferred embodiment of the dissipation enhanced vented muffler described, the neck 6 and the cavity 7 form a Helmholtz resonator.

In the preferred embodiment of the dissipation enhanced vented muffler, the neck 6 is embedded in the cavity 7 and the neck 6 is located in the middle of the cavity 7.

In a preferred embodiment of the dissipation enhanced vented muffler, the neck is a cylindrical structure recessed in the cavity.

In the preferred embodiment of the dissipation enhanced ventilated muffler, the cylindrical structure is communicated with the ventilating duct and the cavity, the radius of the inner wall of the cylindrical structure is Ra, and the height of the cylindrical structure is La.

In the preferred embodiment of the dissipation-enhanced vented muffler, the deployment angle T of the cavity 7 is 30-163.7 °, the radius Ra of the neck 6 is 22-29mm, and the height La of the neck 6 is 25-69.5mm.

In the preferred embodiment of the dissipation enhanced ventilated muffler, the inner circle radius Rc1 of the cavity 7 is 124.5mm, the outer circle radius Rc2 is 200mm, the total thickness Dc of the cavity 7 is 66.5mm-128.5mm, wherein the wall thickness of the inner side and the outer side of the cavity 7 is 0.5mm, and the wall thickness of the neck 6 is 1mm. The advantage of these parameters is that the muffler has an optimal sound damping effect at 100Hz and its frequency multiplication, and on this basis the thickness of the muffler is reduced as much as possible.

In the preferred embodiment of the dissipation enhanced ventilated muffler, the peak sound absorption frequency of the ventilated muffler is consistent with the frequency of the transformer noise.

In the preferred embodiment of the dissipation enhanced ventilated muffler described, the sound absorption frequency of the sound absorption unit 3 is 100Hz and its multiple.

In the preferred embodiment of the dissipation enhanced ventilated muffler, a plurality of sound absorbing units 3 are formed in a ring-shaped structure around the outside of the ventilation duct 1.

In one embodiment, the dissipation enhanced ventilated muffler comprises a ventilation duct 1, a baffle 2 and several sound absorbing units 3; the ventilation pipeline 1 is a circular pipeline with two open ends and is made of rigid materials and is connected with the neck 6 of the sound absorption unit 3; the sound absorption unit 3 adopts a Helmholtz resonance structure and consists of a thinner neck 6 and a cavity 7 with a larger volume, the neck 6 is embedded in the cavity 7, and the neck 6 is positioned in the middle of the cavity 7; the partition plate 2 comprises a ring 4 and a number of cuboids 5, wherein the ring 4 is concentric with the ventilation duct 1, and the cuboids 5 connect the outside of the ring 4 and the inside of the duct along the radius of the ventilation duct 1 and open next to the neck 6 of the sound absorbing unit 3.

In one embodiment, the dissipation enhanced ventilated muffler is adapted for transformer room noise reduction. Because the main frequency of the noise of the transformer is 100Hz and the frequency multiplication thereof, the target silencing frequencies of the silencer provided by the example are 100Hz, 200Hz, 300Hz, 400Hz and 500Hz. When an acoustic wave is incident, the acoustic wave of a target frequency resonates in the muffler, energy is dissipated, and the remaining acoustic wave propagates through the ventilation duct 1. The proposed enhanced dissipation ventilated muffler for a transformer room is shown in fig. 1. The muffler consists of a ventilation duct 1, a partition plate 2 and a sound absorption unit 3. Wherein the ventilation duct 1 is a circular channel and is made of rigid materials; the baffle plate 2 comprises a circular ring 4 and a plurality of cuboids 5, wherein the circular ring 4 is concentric with the ventilation pipeline 1, the cuboids 5 are connected with the outer side of the circular ring 4 and the inner side of the pipeline along the radius of the ventilation pipeline 1 and are close to the opening of the neck 6 of the sound absorption unit 3, and the sound absorption unit 3 consists of a thinner neck 6 and a bigger cavity 7, as shown in figure 2; the opening of the neck 6 is connected with the ventilation pipeline 1 and is adjacent to the baffle plate 2; the plurality of sound absorbing units 3 are closely connected in a ring 4 shape, and when the sound absorbing units cannot be connected in the ring 4, the vacant parts need to be complemented by rigid materials.

The structure of the muffler is entirely determined by the sound absorbing unit 3, and the structure of the sound absorbing unit 3 can be determined by 6 parameters, namely: radius Ra of neck 6, height La, inner radius Rc1 of cavity 7, outer radius Rc2 of cavity 7, angle T of cavity 7, and thickness Dc of cavity 7 are shown in fig. 3. Wherein Rc1 and Rc2 are fixed to 124.5mm and 200mm, respectively; the parameters except the parameter T all comprise wall thickness; the wall thickness of the inner side and the outer side of the cavity 7 of the sound absorption unit 3 is 0.5mm; the wall thickness of the front side and the rear side of the cavity 7 of the sound absorption unit 3 is 0.5mm; the angle of rotation of the wall between the two sound absorbing units 3 is 1 °; the wall thickness of the neck 6 of the sound absorption unit 3 is 1mm; the remaining critical dimensions are shown in table 1.

TABLE 1

	Ra/mm	La/mm	T/deg	Dc/mm
					Sound absorbing unit 31	22	46	163.7	128.5
Sound absorbing unit 32	28	32	34	128.5
					Sound absorbing unit 33	30.7	30	89	128.5
Sound absorbing unit 34	28	25	37.8	72.5
					Sound absorbing unit 35	29	69.5	30	66.5

A model was constructed based on the above parameters and its transmission loss was calculated by simulation, and the results are shown in fig. 4. The proposed structure has obvious loss to noise of 100Hz, 200Hz, 300Hz, 400Hz and 500Hz, and the minimum transmission loss is 16dB. In addition, the transmission loss of the muffler without the partition plate 2 in the case of the same parameters was also calculated, and the result is shown in fig. 5. In contrast, the separator 2 significantly reduces the peak frequency of the transmission loss of the structure, and can achieve the purpose of reducing the muffler size.

The basic principles of the present application have been described above in connection with specific embodiments, however, it should be noted that the advantages, benefits, effects, etc. mentioned in the present application are merely examples and not limiting, and these advantages, benefits, effects, etc. are not to be considered as necessarily possessed by the various embodiments of the present application. Furthermore, the specific details disclosed herein are for purposes of illustration and understanding only, and are not intended to be limiting, as the application is not intended to be limited to the details disclosed herein as such.

The foregoing description has been presented for purposes of illustration and description. Furthermore, this description is not intended to limit the embodiments of the application to the form disclosed herein. Although a number of example aspects and embodiments have been discussed above, a person of ordinary skill in the art will recognize certain variations, modifications, alterations, additions, and subcombinations thereof.

Claims (10)

1. A dissipation-enhanced ventilated muffler, characterized in that it comprises,

the air passage is provided with a plurality of air passages,

a baffle plate arranged in the ventilation pipeline, the baffle plate comprises a circular ring which is concentric with the circular channel and a plurality of cuboids which radiate outwards from the outer wall of the circular ring,

the sound absorption unit surrounds the outer side of the ventilating duct, the sound absorption unit comprises a neck and a cavity connected with the neck, and an opening of the neck is communicated with the ventilating duct and located between two adjacent cuboids.

2. The dissipation enhanced vented muffler of claim 1, wherein the neck and the cavity preferably form a helmholtz resonator.

3. The dissipation enhanced vented muffler of claim 1, wherein the neck is embedded within the cavity and the neck is intermediate the cavity.

4. The dissipation enhanced vented muffler of claim 1, wherein the neck is a cylindrical structure recessed in the cavity.

5. The dissipation enhanced ventilated muffler of claim 4, wherein the cylindrical structure communicates with the vent conduit and the cavity.

6. The dissipation enhanced ventable muffler of claim 5 wherein the expansion angle T of the chamber is 30-163.7 °.

7. The dissipation enhanced ventilated muffler of claim 1, wherein the cavity has an inner circle radius Rc1 of 124.5mm and an outer circle radius Rc2 of 200mm.

8. The dissipation enhanced ventilated muffler of claim 1, wherein a peak sound absorption frequency of the ventilated muffler coincides with a frequency of transformer noise.

9. The dissipation enhanced ventilated muffler of claim 1, wherein the sound absorption frequency of the sound absorption unit is 100Hz and multiples thereof.

10. The dissipation enhanced ventilated muffler of claim 1, wherein a plurality of sound absorbing units are formed in a ring-shaped structure around the outside of the ventilation duct.