CN102522079A - Impedance compound right-angled muffler - Google Patents

Abstract

The invention discloses a full-frequency sound-absorbing impedance composite right-angle muffler. The resistive noise-absorbing structure is composed of the muffler shell and the sheet-type sound-absorbing body, which can block the airflow channel in the muffler that propagates sound waves in a straight line along the axial direction, and the arc-shaped flow-guiding sound-absorbing body of the right-angle resistive sound-absorbing structure directly faces the airflow direction Form a resistant structure, block the passage of low-frequency noise, and increase the absorption of low-frequency noise. Both ends of the sheet-type sound-absorbing body are equipped with arc-shaped flow-guiding sound-absorbing bodies with arc-shaped and right-angled resistant noise-absorbing structures, which help to improve aerodynamic performance. The invention has good sound-absorbing performance and process performance, and the resistive sound-absorbing structure and the right-angle resistive sound-absorbing structure can be combined according to specific installation conditions, and the adaptability is strong.

Description

Impedance Composite Right Angle Muffler

technical field

The present invention relates to a muffler, in particular to a muffler with impedance composite broadband.

Background technique

The ventilation muffler, referred to as the muffler for short, is an acoustic device that prevents sound transmission and allows airflow to pass through. In places that need to keep low background noise and block the influence of external noise, and in places with high noise to prevent the impact of noise on the surrounding environment, and at the same time, ventilation is required, mufflers are required. Mufflers are widely used in architectural acoustics and noise control engineering. There are many types of mufflers, and the muffler mechanism includes resistive muffler, resistive muffler, impedance compound muffler, etc. The common muffler adopts a resistive plate muffler, which has the characteristics of simple structure, but it has an unsatisfactory muffler effect on low-frequency noise, and the existence of the space between the plates will cause high-frequency failure. The resistance muffler is a reflection and interference of sound energy caused by the change of the impedance caused by the sudden change of the pipe section or the side-connected resonant cavity during the sound propagation process, thereby reducing the sound energy radiated from the muffler to achieve the purpose of noise reduction muffler.

Impedance composite muffler refers to a muffler that properly combines sound absorption and sound reflection. At the same time, it has the characteristics of resistive muffler to eliminate medium and high frequency noise and resistive muffler to eliminate low and medium frequency noise, and has a wide-band noise reduction effect. Impedance compound muffler is a combination of resistive muffler with remarkable effect on high and medium frequency noise and resistive muffler with remarkable effect on middle and low frequency noise. However, the existing impedance composite mufflers have relatively large wind resistance, and the resistant part does not have the function of absorbing high-frequency noise. At the same time, the standard specifications are uniform, and it is difficult to adjust the structure according to the actual conditions of the project.

Contents of the invention

In order to overcome the disadvantages of the existing impedance composite muffler that the wind resistance is relatively large and the resistant part does not have the function of absorbing high-frequency noise, the present invention provides an impedance composite right-angle muffler, the resistant part of which has the ability to absorb mid-low frequency and high-frequency noise at the same time High-efficiency impedance composite muffler with low wind resistance. The structure can be adjusted according to the actual conditions of the project.

In order to achieve the above purpose, the technical solution of the present invention is: the resistive noise-absorbing structure is composed of sheet-type sound-absorbing bodies. The sound-absorbing body is composed of two sides of the inner sound-absorbing material covered with glass cloth and a perforated face plate. The perforated face plate at both ends of the sheet-type sound-absorbing body is in the shape of an arc, and the arc shape is facing the direction of the airflow, which is conducive to the aerodynamic performance. improvement. The resistant structure is composed of a right-angled resistant structural cube with an arc-shaped flow guide and sound-absorbing body, four of which are the inner wall of the muffler shell, one side is a resistive sound-absorbing structure, and the other side is the air outlet louver or the air inlet flange interface . The right-angle cavity area formed between the arc-shaped flow guide and sound-absorbing body of the right-angle resistant sound-absorbing structure and the inner wall of the muffler shell, the arc-shaped flow guide and sound-absorbing body directly faces the airflow direction to form a resistant structure, although the low frequency band is due to The frequency and wavelength are long and the diffraction ability is strong. However, the existence of the right-angle cavity region makes the sound energy continuously refracted in the cavity region, and the sound energy passing through the right-angle cavity region will be absorbed faster, absorbing non-plane waves more effectively, and can Eliminates noise whose frequency characteristics are dominated by low-frequency bands. It can block the airflow passage of the sound wave propagating in a straight line in the axial direction in the muffler, which can effectively prevent the high-frequency failure in the traditional resistive plate muffler. The inner wall of the muffler and the arc-shaped guide sound-absorbing body are provided with sound-absorbing materials, and the sound-absorbing materials are covered with glass cloth, and the surface is provided with a protective perforated plate. Both ends of the sheet-type sound-absorbing body are provided with arc-shaped flow-guiding sound-absorbing bodies with arc-shaped and right-angled resistant noise-absorbing structures, which help to improve aerodynamic performance.

 If the airflow contains dust, water vapor, oil gas, acid-base substances and other impurities, the glass cloth covered outside the sound-absorbing material should be replaced with a weather-resistant plastic film. Adding weather-resistant plastic film will increase the absorption of medium and low frequencies. It is generally believed that the thickness of weather-resistant plastic film can be between 100μ~10μ. However, if the thickness is 100μ, the high-frequency absorption will be reduced, and if the thickness is 10μ, the strength of the weather-resistant plastic film will be affected. The invention adopts a weather-resistant plastic film with a thickness of about 50 μ, which not only helps to improve the sound absorption coefficient of the middle and low frequencies, but also ensures the use function of the sound-absorbing material.

The sound-absorbing body, inside the muffler shell and the arc-shaped guide can also be folded into the same shape of the sound-absorbing body by using sound-absorbing perforated plates such as foamed aluminum plates, and installed on the muffler shell instead of sound-absorbing materials, glass cloth and perforated panels for face protection. in vivo.

The sheet sound absorbing body, the inside of the muffler shell and the arc guide sound absorbing body can also use the hard sound absorbing board with good sound absorption performance, cut into the sound absorbing body of the same shape, and replace the sound absorbing material, glass cloth and protective surface The perforated plate fits inside the muffler housing.

According to the conditions of the project site, the resistive sound-absorbing structure and the right-angle resistive sound-absorbing structure can be combined according to the specific installation conditions, air inlet pressure, air volume, and noise reduction. For example, due to the limitation of specific installation conditions, the sheet-type sound-absorbing body can be arranged in a ladder shape, and the right-angle resistant noise-absorbing structure can be set in a right-angle trapezoidal shape. At the same time, no arc-shaped guide sound-absorbing body is installed.

The beneficial effects of the present invention are: the combination of the resistive noise-absorbing structure and the right-angle resistant noise-absorbing structure can achieve the purpose of full-frequency noise elimination, and the two ends of the sheet-type sound-absorbing body are provided with arc-shaped and right-angle resistant noise-absorbing structures. The arc-shaped guide and sound-absorbing body contributes to the improvement of aerodynamic performance. The resistive sound-absorbing structure and the right-angle resistive sound-absorbing structure can be combined according to specific installation conditions, air inlet pressure, air volume, and sound-absorbing volume, etc., with strong adaptability.

Below in conjunction with accompanying drawing and specific embodiment the present invention will be further described.

Description of drawings

Figure 1 is a front view structural diagram of the first embodiment of the present invention;

Figure 2 is a side view of Figure 1;

Figure 3 is a top view of Figure 1;

Figure 4 is a partial structural diagram of A in Figure 1;

Figure 5 is a partial structural diagram of B in Figure 3;

Figure 6 is a front view structural diagram of the second embodiment of the present invention;

Figure 7 is a front view structural diagram of the third embodiment of the present invention;

Figure 8 is a frontal view of the fourth embodiment of the present invention;

Figure 9 is a frontal view of the fifth embodiment of the present invention;

Figure 10 is a frontal view of the sixth embodiment of the present invention;

Figure 11 is a frontal view of the seventh embodiment of the present invention;

Figure 12 is a frontal view of the eighth embodiment of the present invention;

In the figure 1. By the muffler shell, 2. Resistive noise reduction structure, 3. Right-angle resistance noise reduction structure, 4. Flange interface, 5. Air outlet louver, 6. Chip sound absorbing body, 7. Positioning Device, 8. arc shape, 9. sound-absorbing material, 10. glass cloth, 11. perforated panel, 12. arc-shaped guide and sound-absorbing body, 13. cube, 14. right-angle cavity area, 15. right-angle Trapezoid, 16. Weather-resistant plastic film, 17. Sound-absorbing perforated sheet, 18. Hard sound-absorbing board.

Detailed ways

In the first embodiment shown in Figures 1, 2, 3, 4, and 5, the muffler housing (1), the resistive sound-absorbing structure (2), the right-angle resistive sound-absorbing structure (3), and the flange interface ( 4) Impedance composite right-angle muffler composed of air outlet louvers (5). The sheet-type sound-absorbing body (6) of the resistive noise-absorbing structure (2) is installed in the muffler shell (1) using a positioner (7), and is arranged in parallel along the airflow direction. The sheet-type sound-absorbing body is composed of (6) inner sound-absorbing material (9) covered with glass cloth (10) on both sides and the perforated face plate (11), and the face-protecting perforated plates (11) into an arc shape (8). The two sides of the resistive noise-absorbing structure (2) are right-angled resistant noise-absorbing structures (3), and the right-angled resistant noise-absorbing structures (3) are composed of cubes (13) with arc-shaped flow-guiding and sound-absorbing bodies (12), Among them, four sides are the inner wall of the muffler shell (1), one side is the resistive noise reduction structure (2), and the other side is the air outlet louver (5) or the air inlet flange interface (4). The inner wall of the muffler shell (1) and the arc-shaped flow-guiding sound-absorbing body (12) are provided with sound-absorbing materials (9), covered with glass cloth (10), and the surface is provided with a protective perforated plate (11).

In the second embodiment shown in Figure 6, according to the actual situation of the project, the muffler shell (1) and three right-angle resistive noise-absorbing structures (3), two resistive noise-absorbing structures (2), and a flange The interface (4) is a combined impedance composite right-angle muffler with an air outlet louver (5). The characteristics of this embodiment are: strong adaptability and large noise reduction capacity, especially suitable for the air inlet and outlet muffler of the sound insulation testing room.

In the third embodiment shown in Figure 7, according to the actual situation of the project, the muffler shell (1) and two right-angle resistive noise-absorbing structures (3) three resistive noise-absorbing structures (2) and one flange interface ( 4) A combined impedance composite right-angle muffler with an air outlet louver (5). The characteristics of this embodiment are: according to the installation conditions, it can be combined freely through the flange interface, with strong adaptability and large noise reduction.

In the fourth embodiment shown in Figure 8, if due to the limitation of specific installation conditions, the sheet-type sound absorbing body (6) can be arranged in a ladder shape, and the right-angle resistant sound-absorbing structure (3) can be arranged in a right-angle trapezoid (15), and at the same time , no arc-shaped guide and sound-absorbing body (12) is provided. The characteristics of this embodiment are: strong adaptability, simple structure, low cost, and wide application, especially suitable for noise reduction of air entering and exiting sound-proof enclosures and sound-proof rooms.

In the fifth embodiment shown in Figure 9, according to the actual situation of the project, the muffler shell (1) and four right-angled trapezoidal (15) right-angle resistant noise-absorbing structures (3) and two sheet-type sound-absorbing bodies (6 ) A resistive muffler structure arranged in a ladder shape (2) A flange interface (4) An air outlet louver (5) A combined impedance composite right-angle muffler. The characteristics of this embodiment are: small occupied space, strong adaptability, and large noise reduction capacity.

In the sixth embodiment shown in Figure 10, if the dust, water vapor, oil gas, acid and alkali substances and other impurities contained in the air flow, the sound absorption of the sheet sound absorber (6) and the inner wall of the muffler shell (1) The glass cloth (10) covered by the material (9) is replaced with a weather-resistant plastic film (16) to ensure the use function of the sound-absorbing material.

In the seventh embodiment shown in Figure 11, the sheet-type sound absorbing body (6), the inside of the muffler shell (1) and the arc-shaped guide sound-absorbing body (12) can also be folded into the same shape using the sound-absorbing perforated plate (17). The shape of the sound-absorbing body replaces the sound-absorbing material (9), the glass cloth (10) and the perforated plate (11) to be installed in the muffler housing (1).

In the eighth embodiment shown in Figure 12, hard sound-absorbing panels with good sound-absorbing performance can also be used in the sheet-type sound-absorbing body (6), inside the muffler shell (1) and the arc-shaped flow-guiding sound-absorbing body (12) (18), cut into sound-absorbing bodies of the same shape, replace the sound-absorbing material (9), glass cloth (10) and perforated plate (11) and install them in the muffler shell (1).

It should be understood that various combinations and changes can be made to the above-mentioned embodiments without departing from the scope of the present invention.

Claims (10)

1. An impedance composite right-angle muffler is characterized in that: it is composed of a muffler housing, a resistive muffler structure, a right-angle resistive muffler structure, a flange interface, and an air outlet louver. 2. The impedance composite right-angle muffler according to claim 1, characterized in that: the resistive noise-absorbing structure is composed of sheet-type sound-absorbing bodies, the axes of the sheet-type sound-absorbing bodies are arranged in parallel along the airflow direction, and the sheet-type sound-absorbing bodies are composed of The inner sound-absorbing material is composed of glass cloth on both sides and the perforated plate for the face protection. The perforated plates for the face protection at both ends are in the shape of an arc. The sheet-type sound-absorbing body is installed in the muffler shell with a positioner. 3. The impedance composite right-angle muffler according to claim 1, characterized in that: the right-angle resistive noise-absorbing structure is composed of a cube and an arc-shaped guide and sound-absorbing body, wherein four sides are the inner wall of the muffler shell, and one side is a resistive noise-absorbing body. Acoustic structure, the air outlet louver on the other side or the flange interface of the air inlet, the arc-shaped flow guide sound-absorbing body and the inner wall of the muffler shell form a right-angle cavity area. 4. The impedance composite right-angle muffler according to claim 1, characterized in that: inside the muffler shell and the arc-shaped flow-guiding sound-absorbing body, sound-absorbing materials are arranged, and the sound-absorbing materials are covered with glass cloth, and the surface is provided with a protective perforated plate . 5. The impedance composite right-angle muffler according to claim 1, characterized in that: if the intake airflow contains other impurities, the outer covering of the sound-absorbing material can be replaced by a weather-resistant plastic film with glass cloth, and the surface is provided with a protective perforated plate. 6. The impedance composite right-angle muffler according to claim 2, characterized in that: the number of sheet-type sound-absorbing bodies of the resistive noise-absorbing structure can be adjusted according to the air volume, and the length of the sheet-type sound-absorbing bodies can be adjusted according to the noise reduction requirements. Adjustment. 7. The impedance composite right-angle muffler according to claim 1, characterized in that: the resistive noise-absorbing structure and the right-angle resistive noise-absorbing structure can be combined according to specific installation conditions, air inlet pressure, air volume, and noise reduction. 8. The impedance compound right-angle muffler according to claim 7, characterized in that: due to the limitation of specific installation conditions, the sheet-type sound-absorbing body can be arranged in a ladder shape, and the right-angle resistance muffler structure can be arranged in a right-angle trapezoid, not Set arc-shaped guide and sound-absorbing body. 9. The impedance composite right-angle muffler according to claim 1, characterized in that: the sheet-type sound absorbing body, the inside of the muffler shell and the arc-shaped flow-guiding sound-absorbing body can be folded into sound-absorbing bodies of the same shape by using sound-absorbing perforated plates, Instead of sound-absorbing materials, glass cloth and perforated panels for face protection, it is installed in the muffler shell. 10. The impedance composite right-angle muffler according to claim 1, characterized in that: a hard sound-absorbing board with good sound-absorbing performance can also be used in the sheet-type sound-absorbing body, the inside of the muffler shell and the arc-shaped flow-guiding sound-absorbing body, and cutting A sound-absorbing body of the same shape is installed in the muffler shell instead of sound-absorbing materials, glass cloth and perforated panels for face protection.

Images