Muffler is an effective device for controlling the external propagation of aerodynamic noise. Acoustic treatment inside can greatly reduce the generation and propagation of noise without affecting the passage of airflow. After installing the muffler, the noise level of the equipment should reach 20-40dB (A), and the subjective perceived loudness should be reduced by 50-90% accordingly.

Types of mufflers for Roots blowers

1. Resistance silencers have the characteristics of absorbing mid to high frequency sounds and being easy to manufacture. They are generally used for noise reduction in fans such as air conditioning fans, compressors, gas turbines, and blowers.

2. The resistant muffler has the characteristics of strong targeting, good sound absorption effect for medium and low frequencies, and no use of sound absorbing materials. Usually, it can only be used for exhaust noise reduction in small pipelines, such as automobiles, ships, diesel engines, etc.

3. Impedance type mufflers have characteristics such as noise frequency bandwidth and safe use. Mainly used for silencing mid frequency broadband noise with high sound level but low frequency. Steam turbine, deaerator, expansion vessel, small displacement safety valve exhaust, etc.

4. The small hole muffler has low to medium frequency broadband noise reduction performance. The small hole diameter increases the sound absorption coefficient, the low hole gap increases the width of the sound absorption band, and the depth of the orifice plate can change the position of the resonance absorption peak. Small hole silencers have the advantages of strict design, wide absorption bandwidth, low resistance, high temperature resistance, and long service life. Generally used for exhaust and venting of high-pressure equipment such as boilers and compressors.

5. Anti spray composite muffler has the advantages of reducing audio frequency bandwidth, wide range of use, large noise reduction, high temperature and pressure resistance, and is not afraid of water vapor and oil mist. Based on the well-known Chinese sound engineer Ma Dayou's theory of small hole injection noise reduction, it has been successfully developed and is currently the latest structure of exhaust muffler in China, widely used in power plants.

6. The through-hole diffusion type muffler has the advantages of smooth exhaust, high temperature resistance, and anti-interference. Usually used for exhaust noise reduction in safety valves, exhaust valves, steam turbines, and blowpipes.