Our GF series of fan mufflers are designed to control and reduce aerodynamic noise caused by fans on the environment. They are used for noise attenuation in the intake and exhaust ducts of various centrifugal and ventilation fans.
Fans are a type of general machinery equipment with a wide range of applications, indispensable in the production of various industries such as power, mining, machinery, metallurgy, and chemical engineering. The noise generated during the operation of fans often becomes a source of health issues for workers and interference. Particularly, fans located near residential areas, with their intake and exhaust airflows emitting aerodynamic noise, are a major factor contributing to environmental pollution, creating public nuisances. They have become one of the main targets for pollution control efforts by China's industrial sector in recent years.
Industrial fans, designed for continuous operation. The International Organization for Standardization (ISO) sets noise standards for such equipment at ≤90 decibels. Our country's new standards are identical, serving as the basis for industrial enterprises to meet continuous noise requirements. However, without noise reduction measures, the noise emitted from the intake and exhaust of the fan can reach 110-120 decibels, significantly exceeding the standard requirements.
This muffler series is of the impedance-type acoustic flow design. Our factory determines the required level of sound attenuation for the design of the absorptive panel structure and fluid channels based on frequency characteristics obtained from actual field noise source tests at power plant fan operation sites. We also employ narrow rectangular channels with a large absorptive material surface to enhance absorption. This product utilizes resistive structures for high and medium-frequency noise attenuation and resistive structures for medium and low-frequency noise attenuation. Additionally, it incorporates both high and low-frequency attenuation zones within the resistive channels to maximize the broadening of the attenuation frequency range, achieving excellent noise reduction performance.
After installation according to the user's requirements, the maximum noise level of this product will not exceed 75-80 decibels. The muffler described in this manual is suitable for all types of centrifugal and axial flow fans. In addition, our factory also designs and produces mufflers for various applications such as gas turbines, Roots blowers, air compressors, and diesel engine exhausts. Welcome to inquire and purchase.
Dampers for fans, fan silencers, exhaust pipe silencers, and exhaust blower silencers are all designed with a resistive sound absorption and noise reduction principle that effectively handles mid to high-frequency broadband characteristics, a reactive sound absorption and noise reduction principle that is beneficial for low to mid-frequency and pulsating characteristics, and micro-perforated silencers and impedance composite silencers.
A resistive silencer is an absorbing type of silencer, which is generally categorized into straight tube, plate, corrugated, honeycomb, acoustic flow, labyrinth, and elbow designs, depending on the structure of the air flow channel. It utilizes the friction and viscosity resistance during the propagation of sound waves through porous absorbent materials to convert sound energy into heat and dissipate it, thereby achieving the purpose of noise reduction. It is the most widely used type of silencer among all.
The resistance silencer differs from the resistive silencer in its noise reduction principle; it does not directly absorb sound energy but utilizes abrupt interfaces or auxiliary resonance chambers on the pipe to cause certain frequencies of sound waves propagating along the pipe to reflect and interfere at the interfaces, thereby achieving the purpose of noise reduction. It is categorized into expansion chamber silencers and resonance silencers.
In actual noise control engineering, noise is often wideband. Typically, a combination of resistive sound absorption and resistive silencing structures is used to control high-intensity wideband noise.
1. Acoustic flow impedance ventilation, exhaust pipeline, and fan silencer (fan muffler) structural principle:
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 acoustic material surface has been adopted to enhance absorption. Furthermore, at the highest noise level, the frequency spectrum of the fan's noise source often includes more than one value, and the noise reduction requirements vary for different frequency bands.
The GF series silencers for ventilation ducts and exhaust fans are both of impedance type, utilizing resistive structures that absorb and suppress high and mid-frequency noise, as well as resistive structures that suppress and reduce mid and low-frequency noise. Additionally, both high and low-frequency sound-absorbing and suppressing zones are incorporated into the resistive channels to maximize the broadening of the sound suppression frequency range, achieving an excellent noise reduction effect.
The GF series exhaust silencers for ventilation duct fans and exhaust silencers for blowers are suitable for all types of centrifugal, axial, Roots blowers, and air compressors.
2. Impedance-type aerodynamic muffler (Fan muffler) - Applications and Product Features:
Fans are a type of general mechanical equipment with a wide range of applications, essential in industries such as power, mining, machinery, metallurgy, and chemical engineering. The noise generated during their operation often becomes a source of harm to workers' health and environmental disruption. Particularly, fans located near residential areas, with their intake and exhaust airflows radiating aerodynamic noise, are a major factor in environmental pollution, causing public nuisances. They have been one of the primary targets for noise pollution control efforts by China's industrial sector in recent years.
Industrial fans, which are equipment designed for continuous operation. The International Organization for Standardization (ISO) sets noise standards for such equipment at ≤90 decibels. Our country's new standards are identical to these, serving as the basis for continuous noise compliance in industrial enterprises. However, without adopting noise reduction measures, the noise emitted from the intake and exhaust openings of the fans can reach 110 to 120 decibels, significantly exceeding the compliance requirements.
This series of silencers (fan silencers) is of impedance type. Our factory determines the required noise reduction levels across various frequency spectrums based on actual test data of noise sources from various fans at power plants, which serves as the primary basis for designing the absorptive panel structure and fluid channels. A narrow rectangular channel with a large surface area of absorbent material is also employed to enhance absorption. We recognize that the noise sources from fans often have multiple frequency values at the peak noise level, and the noise reduction requirements vary for different frequency bands. Therefore, this product utilizes a resistive structure for high and mid-frequency noise reduction and a reactive structure for mid and low-frequency noise reduction. Additionally, two noise reduction zones, one for high frequencies and another for low frequencies, are incorporated into the resistive channel to maximize the width of the noise reduction frequency band, achieving excellent silencing performance.
