INERCO designs and manufactures silencers for low frequency noise (predominant tones of low frequency). It consists of metallic elements of passive performance, designed to get acoustic attenuation by reflections of sound waves. The working principle is the resonance and reflection of waves which are produced in the discontinuities inside the silencer. The silencers are manufactured in steel, with different expansion chambers and resonators designed according to the requirements of acoustic attenuations (attenuations up to 30 dBA).
Generally, this type of silencer is used in:
- Aspiration and discharge of four-stroke engines with turbocharger.
- Discharge of two-stroke engines.
- Aspiration of rotary and alternative blower.
- Discharge of non-centrifugal vacuum pumps.
- Fluid exhaust and ejectors.
The design of the reactive silencers depends on the following factors:
- Fluid conditions: type of fluid, mass flow rate and temperature.
- Incident noise (noise spectrum at the inlet of the equipment).
- Required attenuation, required noise level at the discharge of the silencer or at a specific distance.
- Nominal diameter, material and thickness of the connection pipe.
- Pressure drop required.
- Connection type: flanged or welded.
- Physical space, weight or material restrictions.
- Position and location of the silencer.