Robuste und abstimmbare Schalldämpfer in der Abluft von Fertigungs‐ und Heizungsanlagen

Durable and tunable silencers in the exhaust air of manufacturing and heating systems. The requirements for silencers, which are used as secondary noise control devices in exhaust ducts, are particularly high in industrial plants (e. g. paper and mineral fiber production, painting plants) as well as power stations and combined heat and power stations. This is caused by the load of the exhaust gas flow with residual substances, which clog the surfaces of the silencers and reduce their efficiency. High flow rates, temperatures and humidity are further influences, which may affect the service live of the silencers. Additionally, high attenuation at low frequencies is required, as the sound sources (fans, compressors, turbines and engines) exhibit high contributions in this range. Conventional silencers lead to uneconomic solutions under these conditions. This problem is treated here and silencer developments are presented that are durable and tunable with respect to the specific need and frequency range. The operating principle and the construction of the silencers, which consist of panel, cavity and active resonators, are described. Its space and money saving employment are demonstrated with examples realized already in practice. These include the employment of the so‐called Angular Stack Silencer and Cleanable Reactive Silencer as resonators in plants for the paper production and power stations. The employment of active resonators is demonstrated in heating systems. New developments of resistant absorber materials and durable acoustically reacting covers give a survey of innovative solutions.