CN204345874U - Anechoic room ventilation sound-attenuating system - Google Patents

Abstract

The utility model discloses a ventilation and muffler system for an anechoic chamber, which is composed of an air-conditioning air inlet muffler system and an air outlet muffler system. The air-conditioning air-inlet muffler system is composed of a ventilation air-conditioning machine room, an air supply fan, an air-inlet static pressure muffler box, an air-supply composite air duct, a flexible vibration-isolation flange, an impedance composite right-angle muffler, and a diffuse air inlet muffler tuyere; The wind muffler system consists of an inner air outlet disc muffler tuyere, an impedance composite right-angle muffler, a flexible vibration isolation flange, an induced draft composite air duct, an induced draft fan, and an induced draft fan vibration isolation mounting frame. When the air-conditioning system of the anechoic room is turned on, the detection work can be carried out continuously and normally, and the influence of the noise of the air-conditioning system of the anechoic room on the background noise value of the anechoic room can be overcome.

Description

Anechoic room ventilation and muffler system

technical field

The utility model relates to the technical field of noise control, in particular to a ventilation and noise elimination system for an anechoic chamber.

Background technique

The anechoic chamber includes a full anechoic chamber and a semi-anechoic chamber. The anechoic chamber is not only a special laboratory for acoustic testing, but also an important part of the testing system. It is also one of the acoustic testing equipment, and its acoustic performance indicators directly affect The precision of the test. The key technology and main technical index of the anechoic chamber is high sound insulation, so that the anechoic chamber can achieve a low-noise environment. The lower the background noise value in the anechoic chamber, the better the test effect. With the diversification of test samples, the sound level requirements for testing are getting lower and lower. Since the noise around the anechoic room is unavoidable, if the ambient noise around the anechoic room is 65 dB(A) and the background noise value in the anechoic room is required to be 15 dB(A), then the sound insulation of the enclosure structure of the anechoic room Should be ≥50dB(A).

The inspectors working in the anechoic chamber shall ensure their working conditions. According to "Industrial Enterprise Design Hygienic Standards" GBZ 1-2010 Chapter 6 Basic Hygienic Requirements for Workplaces 6.6.1 The fresh air in the workplace should come from the outside, the fresh air outlet should be set in the air clean area, and the fresh air volume should meet the following requirements: non-air-conditioned For workshops where the per capita volume of the workplace is less than 20m3, the per capita fresh air volume should be guaranteed to be ≥30m3/h; 30m3/h, and the per capita fresh air volume in the clean room should be ≥40m3/h. For this reason, the ventilation system that should be equipped in the anechoic room should meet the requirement of per capita fresh air volume. Due to the existence of the ventilation system, the noise transmission path is also formed, forming a weak link in the sound insulation of the enclosure structure of the anechoic room.

According to "Code for Design of Noise Control in Industrial Enterprises" GB/T50087-2013 Chapter 4 Sound Insulation Design Section 3 Selection and Design of Sound Insulation Structure Article 4.3.5 The design of the sound insulation cover shall comply with the following regulations: 5.... …All ventilation, smoke exhaust and production process openings shall be equipped with mufflers, and the sound attenuation capacity shall be equivalent to that of the sound insulation enclosure. The muffler of the ventilation system of the anechoic room should have a noise attenuation capacity of ≥50 dB(A).

According to "Code for Design of Noise Control in Industrial Enterprises" GB/T50087-2013 Chapter 5 Noise Reduction Design Section 1 General Provisions  Article 5.1.3 The noise reduction capacity of the muffler shall be determined according to the noise reduction requirements. Usually the designed noise reduction should not exceed 50dB.

According to the "Technical Specifications for Anechoic Chambers and Semi-Anechoic Rooms" GB50800-2012 7 Public Professionals 7.1 HVAC Design 7.1.3 Noise Control of Air Conditioning System... 2 The noise reduction and noise reduction design of ventilation and air conditioning systems should be based on the interior of the anechoic room The allowable noise level is determined by factors such as equipment noise value, vibration size, frequency characteristics and transmission system noise.

According to the "Technical Specifications for Anechoic and Semi-Anechoic Rooms" GB50800-2012 3 Acoustic Design 3.1 General Provisions 3.1.4 The background noise of the anechoic room or semi-anechoic room. It should be determined according to the test content and test requirements. The background noise value is not only the total sound level value, but also the allowable sound pressure level value of each frequency band.

Since the background noise value of the anechoic room is not only the total sound level value, the allowable sound pressure level value of each frequency band should also be given. According to the law of sound insulation quality, that is, the higher the quality and the thicker the material, the better the sound insulation effect, and the surface density is proportional to the sound insulation. If the frequency is reduced by half, the transmission loss will be reduced by 6dB(A); if the quality is doubled, the transmission loss will be increased by 6dB(A). The requirement of the cut-off frequency in the anechoic room leads to the requirement of low-frequency background noise. Therefore, high requirements are put forward for the isolation and absorption of low-frequency noise in the anechoic ventilation system of the anechoic chamber.

At present, the anechoic chamber ventilation system's low-frequency noise attenuation is the main factor restricting the reduction of background noise in the anechoic chamber.

Contents of the invention

In order to overcome the influence of the noise of the existing ventilation system on the background noise value of the anechoic room, the utility model provides a ventilation and silencing system for the anechoic room, which can effectively eliminate low-frequency noise The impact of the noise can meet the requirements of the low-frequency background noise value in the anechoic room.

The technical scheme adopted by the utility model to solve the technical problem is: a ventilation muffler system for an anechoic room, which is composed of an air-conditioning air inlet muffler system and an air outlet muffler system. The air-conditioning air-inlet muffler system is composed of the air-conditioner room, the air supply fan, the air-inlet static pressure muffler box, the air-supply composite air duct, the flexible vibration-isolation flange, the impedance composite right-angle muffler, and the diffuse air-inlet muffler tuyere; The muffler system consists of an inner outlet disc muffler tuyere, an impedance composite right-angle muffler, a flexible vibration isolation flange, an induced draft composite air duct, an induced draft fan, and an induced draft fan vibration isolation mounting frame.

The air-conditioning machine room is independently set beside the anechoic room, and all the air is fed into the static pressure anechoic box, the external air supply composite air duct, the impedance composite right-angle muffler, the internal air supply composite air duct, and the diffuser through the air supply fan. The air flows into the anechoic opening and the anechoic room; the external air supply composite air duct and the anechoic outdoor sound insulation structure, and the interface between the inner side of the anechoic outdoor sound insulation structure and the internal air supply composite air duct are all equipped with flexible vibration isolation Flange; the impedance composite right-angle muffler and the internal air supply composite air duct are arranged between the sound insulation structure in the anechoic chamber and the external sound insulation structure.

The impedance composite right-angle muffler and the internal air supply composite air duct are arranged between the sound insulation structure in the anechoic chamber and the external sound insulation structure. Prevents low frequency noise from entering the muffler interior from the muffler housing.

The flexible vibration isolation flange interface can prevent low-frequency noise from entering the gap between the sound insulation structure and the external sound insulation structure of the anechoic chamber through the gap between the external sound insulation structure and the composite air duct, and affecting the background noise of the anechoic chamber.

The induced draft fan vibration isolation installation frame is independently installed beside the anechoic chamber, the induced draft fan and the induced draft composite air duct are connected through a flexible vibration isolation flange, and the impedance composite right-angle muffler is arranged on the sound insulation structure outside the anechoic chamber. The sound insulation structure in the anechoic chamber, the impedance composite right-angle muffler between the external sound insulation structure, and the composite wind pipe for introducing air are connected to the inner air outlet disc type muffler port arranged on the sound insulation structure in the anechoic chamber. The combination of the resistive noise-absorbing structure and the right-angle resistive noise-absorbing structure of the impedance composite right-angle muffler can achieve the purpose of full-frequency noise reduction. The deflector absorber contributes to the improvement of aerodynamic performance. The impedance composite right-angle muffler and composite air duct are arranged between the sound insulation structure in the anechoic chamber and the external sound insulation structure, which can prevent low-frequency noise from entering the interior of the muffler from the muffler shell.

The wind pressure of the air supply fan is greater than the wind pressure loss along the way and the local wind pressure of the air-conditioning air inlet noise reduction system, and the wind pressure of the induced draft fan is greater than the wind pressure loss along the way and the local wind pressure of the air outlet noise reduction system. Wind pressure, the wind pressure margin of the air supply fan is greater than that of the induced draft fan. When the anechoic chamber is working, the room is in a normal positive pressure state, and the air volume meets the standard of ≥30m3 per person. Since the ventilation and muffler system of the anechoic room is equipped with multiple mufflers, the local wind pressure loss is large. If there are only air inlet or outlet fans, it is difficult to meet the requirements of use. Therefore, both the inlet and outlet fans are equipped with mechanical air supply fans. When the anechoic chamber is working, the indoor is in a normal positive pressure state (the indoor air pressure is greater than the outdoor air pressure), so as to prevent the untreated outdoor air from entering the anechoic chamber to interfere with the indoor air conditioning parameters.

The composite air duct is composed of a galvanized sheet outer tube coated with a damping layer material and an inner air duct lined with a composite glass fiber board. Coating damping material inside the outer pipe of galvanized sheet can improve the sound insulation of low-frequency noise of the outer pipe of galvanized sheet. Noise reduction ability.

The vibration isolation mounting frame of the induced draft fan is installed on the ground outside the anechoic chamber. The induced draft fan and the induced draft fan installation frame are connected by a spring suspension rod. The fan mounting frame is not connected with the sound insulation structure outside the anechoic chamber, in order to prevent the solid transmission of vibration.

The beneficial effect of the utility model is that the noise reduction of the ventilation and noise elimination system can be equivalent to the sound insulation of the anechoic chamber. When the air-conditioning system of the anechoic room is turned on, the detection work can be carried out continuously and normally, and the influence of the noise of the air-conditioning system of the anechoic room on the background noise value of the anechoic room can be overcome.

Description of drawings

Below in conjunction with accompanying drawing and embodiment the utility model is further described.

Fig. 1 is a longitudinal sectional structural diagram of an embodiment of the ventilation and muffler system of the anechoic chamber.

FIG. 2 is a top sectional view of FIG. 1 .

Fig. 3 is a longitudinal sectional structure diagram of the composite air supply pipe.

In the figure 1. Ventilation and air conditioning machine room, 2. Air supply fan, 3. Air inlet static pressure muffler box, 4. Composite air duct, 5. Flexible vibration isolation flange, 6. Impedance composite right-angle muffler, 7. Dispersed flow inlet Wind muffler outlet, 8. Wind disk type muffler tuyere, 9. Induced fan, 10. Vibration isolation mounting frame, 11. Inside the anechoic chamber, 12. External sound insulation structure, 13. Internal sound insulation structure, 14. Plating Zinc plate, 15. Damping layer, 16. Composite fiberglass board, 17. Ground.

Detailed ways

In the embodiment shown in Figure 1, a ventilation and noise reduction system for an anechoic chamber is composed of an air-conditioning air inlet noise reduction system and an air outlet noise reduction system. The air-conditioning air-inlet muffler system consists of ventilation and air-conditioning machine room (1), air-supply fan (2), air-inlet static pressure muffler box (3), air-supply composite air duct (4), flexible vibration-isolation flange (5), Impedance compound right-angle muffler (6), diffuse flow air inlet muffler tuyere (7); the air outlet muffler system consists of inner air outlet disc type muffler tuyere (8), impedance compound right-angle muffler (6), flexible vibration isolation method Blue (5), induced draft composite air duct (4), induced draft fan (9), induced draft fan vibration isolation mounting frame (10).

The ventilation and air-conditioning machine room (1) is independently installed beside the anechoic room, and the air is passed through the air supply fan (2) into the air static pressure anechoic box (3), the external air supply composite air duct (4), the impedance Composite right-angle muffler (6), internal air supply composite air duct (4), scattered air inlet muffler (7), anechoic chamber (11); the external air supply composite air duct (4) and Flexible vibration isolation flanges (5) are provided on the inner side of the acoustic outdoor sound insulation structure (12), the inner side of the anechoic outdoor sound insulation structure (12) and the internal air supply composite air duct (4); the impedance composite right-angle muffler ( 6). The inner composite air supply pipe (4) is arranged between the sound insulation structure (13) and the outer sound insulation structure (12) in the anechoic chamber. The induced draft fan vibration isolation installation frame (10) is independently arranged beside the anechoic chamber, the induced draft fan (9) and the induced draft composite air duct (4) are connected through a flexible vibration isolation flange (5), and the outgoing air muffler (1 ) is set on the sound insulation structure (12) outside the anechoic chamber, through the impedance composite right-angle muffler (6) and the composite air duct (4) Connect with the inner air outlet disc type muffler port (8) arranged on the sound insulation structure (13) in the muffler room.

The wind pressure of the air supply fan (2) is higher than the wind pressure loss and local wind pressure of the air-conditioning air inlet noise reduction system, and the wind pressure of the induced draft fan (9) is higher than the wind pressure loss of the air outlet noise reduction system. Wind pressure loss and local wind pressure, the wind pressure margin of the air supply fan (2) is greater than that of the induced draft fan (9), when the anechoic room is working, the room is in a normal positive pressure state, and the air volume meets the requirements of each person ≥30m3 standard. The composite air duct (4) is composed of a galvanized sheet (14) outer tube coated with a damping layer (15) and an inner tube lined with a composite glass fiber board (16). The vibration isolation installation frame (10) of the induced draft fan is installed on the ground (17) outside the anechoic chamber.

Air flow direction in the anechoic room: air conditioning machine room (1) (adjusting temperature, humidity,) → air supply fan (2) → air inlet static pressure anechoic box (3) → external air supply composite air duct (4) → flexible vibration isolation Flange (5) → Impedance Composite Right Angle Muffler (6) → Internal Air Supply Composite Air Duct (4) → Dispersed Air Inlet and Muffler Tuyere (7) → Anechoic Chamber Interior (11) → Outlet Disc Type Muffler Tuyere (8) → Inner induced air composite air duct (4) → Impedance composite right angle muffler (6) → External induced air composite air duct (4) → Flexible vibration isolation flange (5) → Induced fan (9) → Exhaust gas to the outside emission.

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. All modifications, equivalent replacements and improvements made within the spirit and principles of the present utility model shall be included in the protection scope of the present utility model.

Claims (6)

1. A kind of anechoic room ventilation muffler system, is made up of air-conditioning air inlet muffler system, air outlet muffler system, it is characterized in that: air conditioner muffler system is made up of ventilated air-conditioning machine room, blower fan, air inlet Static pressure muffler box, air supply composite air duct, flexible vibration isolation flange, impedance composite right-angle muffler, diffuse flow inlet muffler tuyere; the air outlet muffler system consists of inner air outlet disc type muffler tuyere, impedance composite right-angle muffler It consists of a muffler, a flexible vibration isolation flange, an induced draft composite air duct, an induced draft fan, and an induced draft fan vibration isolation mounting frame. 2. The anechoic room ventilation and silencing system according to claim 1, characterized in that: the ventilation and air conditioning machine room is independently set beside the anechoic room, and all the air is fed into the static pressure by the air supply fan successively. Anechoic box, external air supply composite air duct, impedance composite right-angle muffler, internal air supply composite air duct, scattered air inlet muffler, and inside the anechoic chamber; the external air supply composite air duct is separated from the anechoic chamber The interface between the sound structure, the inner side of the sound-absorbing outdoor sound-proof structure and the internal air-supply composite air duct is all provided with flexible vibration-isolation flanges; Between external sound insulation structures. 3. The anechoic chamber ventilation and muffler system according to claim 1, characterized in that: the induced draft fan vibration isolation installation frame is independently arranged beside the anechoic chamber, and the induced draft fan and the induced draft composite air duct pass through a flexible Vibration isolation flange connection, through the impedance composite right-angle muffler arranged between the sound insulation structure in the anechoic chamber and the external sound insulation structure, the composite air pipe for introducing air, and the inner air outlet disc type muffler arranged on the sound insulation structure in the anechoic chamber Acoustic connection. 4. The anechoic room ventilation and muffler system according to claim 1, characterized in that: the wind pressure of the air supply fan is greater than the wind pressure loss along the way and the local wind pressure of the air inlet muffler system of the air conditioner, The wind pressure of the induced draft fan is greater than the wind pressure loss and local wind pressure of the air outlet noise reduction system, and the wind pressure margin of the air supply fan is greater than that of the induced draft fan. When the anechoic chamber is working, The room is in a normal positive pressure state, and the air volume meets the standard of ≥30m3 per person. 5. The anechoic room ventilation and muffler system according to claim 1, characterized in that: the composite air duct is made of a galvanized sheet outer tube coated with damping material and lined with a composite glass fiber board air duct. 6. The anechoic chamber ventilation and noise reduction system according to claim 1, characterized in that: the induced draft fan vibration isolation mounting frame is installed on the ground outside the anechoic chamber.