阅读说明：本技术 一种片式消声器结构 (Sheet type silencer structure ) 是由 宋继萍 何鹭凤 林嘉祥 于 2020-12-29 设计创作，主要内容包括：本发明公开一种片式消声器结构,包括消声器壳体、消声插片、气流通道。消声插片包括圆弧形微穿孔进风导流段,三角形穿孔护面板出风导流段,两侧设置穿孔护面板,内填充双面铝箔玻璃棉,玻璃棉密度为24kg/m3～48kg/m3,覆面铝箔厚度为0.05～0.03mm；消声插片厚度为50mm,消声器壳体内壁不设置吸声材料,消声插片之间的气流通道宽度为80mm～100mm。通过在玻璃棉外覆面铝箔,在不增加玻璃棉厚度的条件下,提高对低频声波的吸收,减少片式消声器的体积和造价。有效通风面积比例高,体积小,降低气流流速,减低风压损失。同时具有隔热、防水、防潮及防止粉尘粘连的作用,适应恶劣的工况条件。(The invention discloses a chip silencer structure which comprises a silencer shell, a silencing insertion piece and an airflow channel. The silencing insertion piece comprises a circular arc micro-perforated air inlet guide section, a triangular perforated protective panel air outlet guide section, perforated protective panels are arranged on two sides of the circular arc micro-perforated air inlet guide section, double-sided aluminum foil glass wool is filled in the circular arc micro-perforated air outlet guide section, the density of the glass wool is 24kg/m to 48kg/m for carrying out full-length cultivation, and the thickness of a clad aluminum foil is 0.05 to 0.03 mm; the thickness of the silencing insertion pieces is 50mm, sound absorption materials are not arranged on the inner wall of the silencer shell, and the width of an air flow channel between the silencing insertion pieces is 80 mm-100 mm. By covering the aluminum foil outside the glass wool, the absorption of low-frequency sound waves is improved and the volume and the manufacturing cost of the sheet type silencer are reduced under the condition that the thickness of the glass wool is not increased. The effective ventilation area ratio is high, and is small, reduces the air current velocity of flow, reduces the wind pressure loss. Meanwhile, the heat-insulating waterproof paint has the functions of heat insulation, water resistance, moisture resistance and dust adhesion prevention, and is suitable for severe working conditions.)

1. The utility model provides a piece formula silencer structure, includes silencer casing, noise elimination inserted sheet, airflow channel, characterized by: the silencing insertion piece comprises a circular arc micro-perforated air inlet guide section, a triangular perforated protective panel air outlet guide section, perforated protective panels are arranged on two sides of the circular arc micro-perforated air inlet guide section, double-sided aluminum foil glass wool is filled in the circular arc micro-perforated air outlet guide section, the density of the glass wool is 24kg/m to 48kg/m for carrying out full-length cultivation, and the thickness of a clad aluminum foil is 0.05 to 0.03 mm; the thickness of the silencing insertion pieces is 50mm, sound absorption materials are not arranged on the inner wall of the silencer shell, and the width of an air flow channel between the silencing insertion pieces is 80 mm-100 mm.

2. The chip muffler structure as defined in claim 1, wherein: a plurality of silencing insertion pieces are arranged in each silencer shell, airflow channels among the silencing insertion pieces are consistent, and the airflow channel between one side of each silencer shell and each silencing insertion piece is one half of the airflow channel among the silencing insertion pieces.

3. The chip muffler structure as defined in claim 1, wherein: and adjusting the volume weight of the glass wool and the thickness of the clad aluminum foil according to the frequency spectrum of the airflow noise to form different combinations of the volume weight of the glass wool and the thickness of the clad aluminum foil.

4. The chip muffler structure as defined in claim 3, wherein: when the airflow noise is typical of medium-high frequency noise, the density of the glass wool is 24kg/m for high-speed cultivation, and the thickness of the clad aluminum foil is 0.03 mm; when the typical medium and low frequency noise of air flow noise is generated, the density of the glass wool is 48kg/m for carrying out the thin film glass wool by the thin film glass wool top-down method, and the thickness of the clad aluminum foil is 0.05 mm.

5. A chip muffler structure as defined in claim 3, wherein: according to the requirements of the flow speed and the noise elimination quantity of the air flow, the width of the air flow channel and the length of the noise elimination insert piece are adjusted.

6. The chip muffler structure as defined in claim 1, wherein: the perforated protective panel is a metal perforated protective panel with the aperture of 3mm and the perforation rate of more than or equal to 25 percent.

7. The chip muffler structure as defined in claim 1, wherein: the triangular perforated plate air-out flow guide section of the silencing insertion piece has a triangular apex angle of 90-60 degrees.

Technical Field

The invention relates to a resistive muffler technology, in particular to a chip muffler structure.

Background

The silencer is a device which can not only make the air flow pass through smoothly, but also reduce the noise effectively. The resistive muffler is a muffler which utilizes porous sound-absorbing materials (often called resistive materials) with different structural forms in an airflow pipeline to absorb sound energy and reduce noise. The resistive muffler is the most-used muffler with the most types and the most application in various mufflers, and is particularly the most applied to the mufflers of fan type. The resistive muffler has a wider muffling frequency range, and particularly has remarkable muffling performance in medium and high frequency bands. The silencing performance of a resistive silencer mainly depends on the structural style of the silencer, the sound absorption characteristics of sound absorption materials, the air flow speed passing through the silencer, the effective length of the silencer and the like.

In the field of noise control, ventilation and noise elimination are the only items that need to balance manufacturing and installation costs with long-term operation costs. Therefore, the development of a novel silencer with large silencing quantity, small resistance coefficient and large effective ventilation area is the research and development direction in the industry.

First, several factors that affect the amount of sheet noise cancellation:

1. thickness of glass wool board: the glass wool usually used in the silencing insert sheet has the defects of high attenuation amount to high-frequency noise and low attenuation amount to medium-frequency and low-frequency noise. The thicker the thickness of the glass wool plate in the silencing insert or the higher the density, the better the sound absorption of the middle and low frequency noise. But will increase the volume of the muffler and the manufacturing and installation cost;

2. the distance between the silencing insertion pieces: the narrower the muffler channel, the more sound waves are in contact with the sound-absorbing material, and the better the amount of sound absorption. The wider the muffler channel is, the higher frequency sound waves directly pass through the muffler in a beam shape and rarely contact with the sound absorption layer surface of the inner wall of the pipeline, so that the sound absorption is reduced, the noise elimination effect is reduced, and the phenomenon is called as high frequency failure in engineering;

3. the length of the silencing insertion piece is as follows: effective channel length of mufflerLThe longer the sound wave contacts the sound absorbing material for a longer time, the higher the overall sound attenuation. But the loss of wind pressure along the way is also increased, and the volume of the silencer is also correspondingly increased;

4. effective ventilation area: under the condition that the resistance coefficient of the silencer is certain, the smaller the effective silencing passage sectional area is, the higher the flow rate of gas is, the larger the pressure loss is, and the wind pressure of a fan needs to be increased. Whereby the larger the regeneration noise of the air flow, the lower the amount of noise cancellation.

Current routine choices, relevant data and specification provisions: the density of the centrifugal glass wool plate in the sound attenuation sheet is from 24kg/m to 48kg/m, the thickness of the sound attenuation sheet is from 50mm to 100mm, the thickness of the sound attenuation sheet can be from 150mm to 200mm when the low-frequency noise component is more, and half of the thickness of the sound attenuation sheet is cancelled by the thickness of the sound absorption layer of the shell of the silencer. The distance between the silencing inserting pieces is 100 mm-200 mm, and the effective ventilation area is about 50%.

And II, evaluating the efficiency and the economy: the aerodynamic performance is an important performance index for evaluating the silencer and is also an energy consumption index. When the gas flows through the silencing inserting sheet, the pressure of the resistance fluid rises to generate pressure loss, and in order to offset the pressure loss, the wind pressure of the fan needs to be increased, so that the energy consumption is increased. If the area of the silencing passage is reduced in order to reduce investment, and the wind speed is too high, the noise of the airflow is increased again, and the silencing quantity is reduced. Meanwhile, the long-term energy consumption is increased due to the increase of the pressure loss of the system, and the operation cost is increased.

The silencer resistance coefficient is certain under the condition, gaseous velocity of flow is higher, and loss of pressure is bigger, will reduce gaseous velocity of flow, must increase the volume of silencer, and the great silencer of volume can occupy more building space in actual engineering installation, simultaneously, needs more preparation installation cost, will produce higher set cost.

The mufflers are evaluated in terms of efficiency and economy and are referred to as "evaluation numbersNThe noise reduction amount is large, the evaluation number is high, and the evaluation number is low when the ratio of the sectional area of the muffler to the sectional area of the airflow pipeline is larger.N=L/（S/S ₀ ），

Wherein:L-muffler sound deadening volume (dB);S-muffler cross-sectional area (m);S ₀ -gas flow duct cross-sectional area (m).

Third, regarding aluminium foil glass wool: the aluminum foil glass wool is formed by sticking aluminum foils on two sides of centrifugal glass wool and is used as a sound absorption material of the noise elimination inserting sheet. The aluminum foil as the surface layer of the centrifugal glass wool influences the silencing performance of the sheet type silencer.

Disclosure of Invention

The silencer overcomes the defects of poor silencing effect caused by large insert thickness, wide airflow channel and small effective channel area of the existing resistive silencer. The invention provides a sheet type silencer structure, which improves the absorption of low-frequency sound waves under the condition of reducing the volume weight of glass wool and the thickness of an inserting sheet by adopting a mode of coating aluminum foil on the double surfaces of the glass wool in a silencing inserting sheet, and improves the silencing and noise reduction quantity by reducing the width of an airflow channel. The best efficiency and economic evaluation number are achieved, the volume of the silencer is reduced, and the silencing and noise reduction effects are improved.

The technical scheme of the invention is as follows: a chip silencer structure comprises a silencer shell, a silencing insertion piece and an air flow channel. The silencing insertion piece comprises a circular arc micro-perforated air inlet guide section, a triangular perforated protective panel air outlet guide section, perforated protective panels are arranged on two sides of the circular arc micro-perforated air inlet guide section, double-sided aluminum foil glass wool is filled in the circular arc micro-perforated air outlet guide section, the density of the glass wool is 24kg/m to 48kg/m for carrying out full-length cultivation, and the thickness of a clad aluminum foil is 0.05 to 0.03 mm; the thickness of the silencing insertion pieces is 50mm, sound absorption materials are not arranged on the inner wall of the silencer shell, and the width of an air flow channel between the silencing insertion pieces is 80 mm-100 mm.

The aluminum foil has no air holes, and the aluminum foil mainly transfers sound waves by means of vibration of the aluminum foil and can be regarded as a film resonance sound absorption structure. Compared with the commonly used glass cloth, the aluminum foil can reduce the sound absorption coefficient of the centrifugal glass wool in a high frequency band, and meanwhile, the low-frequency sound absorption performance is improved due to the existence of the film resonance sound absorption effect, so that the absorption frequency spectrum of the aluminum foil glass wool moves towards the low-frequency direction. Because the aerodynamic noise system is mainly full-frequency noise and medium-low frequency, the glass cotton resistive sheet type silencer generally has the defects of insufficient attenuation of medium-low frequency noise and excessive attenuation of high-frequency noise. Therefore, the aluminum foil glass wool is more suitable for the resistance silencer to absorb aerodynamic noise.

The aluminum foil is used as a protective layer of the glass wool, so that the glass wool has the function of preventing the glass cloth from falling slag, the aluminum foil is used as the protective layer to reduce the heat conductivity coefficient of the glass wool, and the aluminum foil has an excellent heat insulation effect; the aluminum foil is used as a protective surface layer, and the closed structure and the compact surface layer enable water vapor to be difficult to permeate, so that the water absorption of the glass wool is reduced; the aluminum foil is used as a protective surface layer, so that the flame retardance of the glass wool is improved; the aluminum foil glass wool is convenient to construct, neat and attractive in appearance, does not irritate skin, does not harm health, and can prevent growth of mold.

The aluminum foil glass wool has relatively higher low-frequency sound absorption capacity compared with the centrifugal glass wool, and is close to the effect of increasing the thickness of the centrifugal glass wool. Therefore, the density of centrifugal glass wool of the silencing insertion piece is selected from conventional 24-48 kg/m high-speed cultivation, and the thickness is selected from the thinnest 50mm, so that the volume of the plate-type silencer can be reduced, and the production cost and the weight of the plate-type silencer can be reduced.

A plurality of silencing insertion pieces are arranged in each silencer shell, airflow channels among the silencing insertion pieces are consistent, and the airflow channel between one side of each silencer shell and each silencing insertion piece is one half of the airflow channel among the silencing insertion pieces. Inside the silencer, do not set up sound absorbing structure all around, the distance between noise elimination inserted sheet and the casing is the half of noise elimination inserted sheet interval. The smaller the cross section area of the air channel between the silencing insertion pieces, the more the sound wave contacts the silencing insertion pieces when passing through, and the larger the silencing quantity. The section of each small channel is small, so that the upper limit failure frequency can be improved, and the high-frequency failure is reduced. On the basis of reducing the thickness of the silencing insertion piece, the width of the silencing channel is reduced. Therefore, the distance between the silencing insertion pieces is selected to be 80-100 mm, the effective ventilation area is 61.5-66%, namely the thickness of the insertion pieces and the thickness of an air layer are 1: 1.6-2, the air speed between the insertion pieces of the silencer with the same volume is lower, the flow resistance of the silencer can be effectively reduced, and the air pressure loss and the airflow regeneration noise are reduced. Or the muffler with smaller volume can achieve the same noise elimination and reduction effect.

And adjusting the volume weight of the glass wool and the thickness of the clad aluminum foil according to the frequency spectrum of the airflow noise to form different combinations of the volume weight of the glass wool and the thickness of the clad aluminum foil. When the airflow noise is typical medium-high frequency noise, the density of the glass wool is 24kg/m and the thickness of the clad aluminum foil is 0.03 mm; when the air flow noise is typical medium and low frequency noise, the density of the glass wool is 48kg/m high-speed polished glass wool, and the thickness of the clad aluminum foil is 0.05 mm. The higher the density of the glass wool and the thicker the thickness of the aluminum foil covering, the absorption of the medium and low frequency sound waves can be improved, and vice versa.

According to the requirements of the flow speed and the noise elimination quantity of the air flow, the width of the air flow channel and the length of the noise elimination insert piece are adjusted. The perforated protective panel is a metal perforated protective panel with the aperture of 3mm and the perforation rate of more than or equal to 25 percent. When the perforation rate of the perforated protective panel is more than or equal to 25 percent, the protective and supporting functions are performed on the aluminum foil glass wool, and the sound absorption influence on the material is relatively negligible. When the hole diameter of the perforation is smaller, the pressure of the airflow on the aluminum foil glass wool in the hole can be dispersed, and the service life of the aluminum foil glass wool is prolonged.

The triangular perforated plate air-out flow guide section of the silencing insertion piece has a triangular apex angle of 90-60 degrees. The triangular air outlet flow guide section is arranged, so that air outlet can be subjected to an expansion slow flow stage, and the air pressure loss of the air outlet section can be reduced. The triangular air outlet flow guide section is provided with a perforated plate, so that the sound absorption quantity of the section can be increased. The smaller the vertex angle of the triangle, the better the slow flow effect, but the setting cost is increased correspondingly.

The invention has the beneficial effects that:

1. the aluminum foil covers the glass wool, so that the absorption of low-frequency sound waves is improved under the condition that the thickness of the glass wool is not increased;

2. by reducing the thickness of the silencing insertion piece, the effective ventilation area is improved, the ratio is high, the size is small, the airflow speed is reduced, and the wind pressure loss is reduced;

3. by reducing the distance between the silencing insertion pieces, the length of the silencing insertion pieces can be reduced, and the silencing and noise reducing effects are improved;

4. the heat-insulating waterproof and moistureproof dust-proof coating has the functions of heat insulation, water resistance, moisture resistance and dust adhesion prevention, and is suitable for severe working conditions;

5. the volume and the cost of the sheet type silencer are reduced while the noise elimination and the noise reduction are the same, and the technical breakthrough of high comprehensive efficiency is realized.

Drawings

The invention is further illustrated by the following figures and examples.

FIG. 1 is a cross-sectional construction view of a sound damping insert.

Fig. 2 is a front sectional configuration view of the embodiment of the present invention.

Fig. 3 is a side view of fig. 2.

Description of reference numerals: 1. a silencer shell 11, an airflow channel; 2. the noise elimination inserted sheet, 21, perforation guard panel, 22, air inlet guide section, 23, air outlet guide section, 3, double-sided aluminum foil glass wool, 31, glass wool, 32, cladding aluminum foil.

Detailed Description

In the embodiment shown in fig. 1, 2 and 3, the sheet type silencer structure comprises a silencer shell (1), a silencing insert (2) and an air flow channel (11). The silencing insertion piece (2) comprises a circular arc micro-perforated air inlet guide section (22), a triangular perforated guard panel air outlet guide section (23), perforated guard panels (21) are arranged on two sides of the circular arc micro-perforated guard panel air outlet guide section, double-sided aluminum foil glass wool (3) is filled in the circular arc micro-perforated guard panel air outlet guide section, the density of the glass wool (31) is 24kg/m for thin film cultivation and 48kg/m for thin film cultivation, and the thickness of the clad aluminum foil (32) is 0.05-0.; the thickness of the silencing insertion pieces (2) is 50mm, sound absorption materials are not arranged on the inner wall of the silencer shell (1), and the width of an air flow channel (11) between the silencing insertion pieces (2) is 80 mm-100 mm.

A plurality of silencing insertion pieces (2) are arranged in each silencer shell (1), airflow channels (11) between the silencing insertion pieces (2) are consistent, and the airflow channel (11) between one side of each silencer shell (1) and each silencing insertion piece (2) is one half of the airflow channel (11) between the silencing insertion pieces (2).

According to the frequency spectrum of the airflow noise, the volume weight of the glass wool (31) and the thickness of the aluminum foil covering (32) are adjusted to form different combinations of the volume weight of the glass wool (31) and the thickness of the aluminum foil covering (32). When the airflow noise is typical medium-high frequency noise, the density of the glass wool (31) is 24kg/m and the thickness of the aluminum foil clad with the film (32) is 0.03 mm; when the air flow noise is typical medium and low frequency noise, the density of the glass wool (31) is 48kg/m and the thickness of the aluminum foil clad laminate (32) is 0.05 mm.

The width of the air flow channel (11) is adjusted according to the requirements of the flow speed and the noise elimination amount of the air flow. The perforated protective panel (21) is a metal perforated protective panel with the aperture of 3mm and the perforation rate of more than or equal to 25 percent. The triangular perforated plate air outlet flow guide section (23) of the silencing insertion piece (2) has a triangular vertex angle of 90-60 degrees.

The present invention is not limited to the above-described embodiments, and various combinations and modifications may be made to the above-described embodiments without departing from the scope of the present invention. Any modification, equivalent replacement, and improvement made within the spirit and principle of the present invention should be included in the protection scope of the present invention.