Centrifugal Fan Muffler Application Scope

The FG Centrifugal Fan Silencer is mainly used for various series of high-pressure centrifugal fans to reduce aerodynamic noise at the inlet and outlet air ports.

The FG type has flange connections on both ends and can be串联 in pipelines. The other end features a rainproof cap, suitable only for outdoor pipeline ends and air intake of enclosed machine rooms.

Section 2: Structure and Principle of Centrifugal Fan Muffler

Centrifugal fan silencers are developed based on the sound-absorbing principle of sound-deadening panels. This type of silencer boasts excellent acoustic performance and good aerodynamic performance; its structure is rational and easy to install. It is a high airflow resistive honeycomb silencer. The reactive section utilizes multi-chamber reactive straight tube channels and cruciform sound-absorbing panels, ensuring sufficient sound absorption over a wide frequency range. The FT type silencer structure is composed of many parallel unit silencer tubes, filled with porous sound-absorbing material between the tubes to reduce radiation noise caused by airflow-induced shell wall vibration. Reinforcing ribs are set on the outer shell to this end.

Aerodynamic silencers, centrifugal fan silencers, and blower silencers are all designed with a resistive noise reduction principle that effectively addresses mid-to-high-frequency broadband characteristics, along with a reactive noise reduction principle that is beneficial for low-to-mid frequencies and pulsating characteristics, as well as micro-perforated silencers and impedance composite silencers.

Airflow mufflers are categorized into: centrifugal fan mufflers, Roots fan mufflers, blower mufflers, and axial flow fan mufflers. Airflow mufflers are primarily used to reduce the aerodynamic noise at various fan inlets, ducts, and enclosed machine room air intake openings.

According to the different structural designs of fan inlets and outlets, they are categorized into circular and rectangular structures.

(1) Circular structures are designed for round air duct outlets and are available in two types: A and B. Type A features flanges at both ends and is directly connected to the pipeline (i.e., pipeline muffler). Type B has one flange and the other end is an open vent to the atmosphere (can be fitted with a rainproof wind cap). It is exclusively suitable for outdoor pipeline ends and intake air openings in enclosed machine rooms.

(2) The resistive sound absorbing panels in circular structures typically have a thickness of 100 mm or 150 mm, offering a noise reduction of 15-30 dB(A). Under wind speeds of 5-12 m/s, they are suitable for air volumes ranging from 1000 to 50,000 m³/h. The structure employs two impedance-based sound absorption zones for both high-frequency and low-frequency noise, to maximize the broadening of the sound absorption frequency range.

Please provide the following information when ordering a fan muffler:

(1) Fan model and application scenarios.

(2) Fan air volume and wind speed

(3) Spout size

Structure and Principle of Airflow Noise Suppressor

Based on the spectral characteristics obtained from actual testing of noise sources at industrial fan operation sites, determine the required noise reduction levels across various frequency ranges for designing acoustic absorbers and fluid channels. Additionally, a narrow rectangular channel with a large surface area of acoustic material covering is employed to enhance absorption. Furthermore, at extremely high noise levels, the noise source of the fan may have multiple spectral values, and the noise reduction requirements for different frequency bands vary accordingly.

These silencers for the ventilation pipe series and exhaust fan are of impedance acoustic flow type. They utilize resistive structures that absorb and reduce high and medium-frequency noise, as well as resistive structures that reduce and absorb medium and low-frequency noise. Additionally, both high and low-frequency acoustic absorption areas are incorporated into the resistive channels to maximize the bandwidth of the noise reduction, achieving excellent sound absorption and noise reduction effects.

Duct silencers and blower exhaust silencers are suitable for various centrifugal, axial flow, Roots blowers, and air compressors.

Application and Product Features of Fan Muffler:

Fans are a general type of mechanical equipment with a wide range of applications, essential in industries such as electricity, mining, machinery, metallurgy, and chemical engineering. The noise generated during their operation often becomes a source of harm to workers' health and environmental disturbance. Particularly, fans located near residential areas, with their intake and exhaust airflow noise, are a major factor in environmental pollution, causing public nuisance. They have been one of the primary targets for noise pollution control efforts by China's industrial sector in recent years.

Industrial fans, continuous-running equipment. The International Organization for Standardization (ISO) specifies noise standards for such equipment as ≤90 decibels. Our new standards are identical to this, serving as the basis for continuous noise compliance in industrial enterprises. However, without the use of noise-reduction measures, the noise emitted from the intake and exhaust outlets of the fan can reach 110-120 decibels, significantly exceeding the compliance requirements.

This series of silencer products is of impedance-type acoustic flow. Our factory determines the necessary noise reduction levels within specific frequency ranges for the design of acoustic absorption panel structures and fluid channels based on actual test data obtained from noise sources in the operation of various fans at power plants. Additionally, narrow rectangular channels with a large surface area of acoustic absorption material are used to enhance absorption effectiveness. We recognize that the noise sources of fans often have multiple frequency values at higher noise levels, and the noise reduction requirements vary for different frequency bands. Therefore, this product employs a resistive structure for high and medium-frequency noise reduction and a reactive structure for medium and low-frequency noise reduction. High-frequency and low-frequency noise reduction zones are also incorporated within the resistive channels to greatly expand the noise reduction frequency range, achieving excellent noise reduction performance.

Once installed according to specifications, this product's maximum noise level will not exceed 85-90 decibels.

If the interface exceeds 1600, please contact us. Our company will design a custom solution for you.