Acoustic and mass characteristics of plate silencers with wedge-shaped outlet fairings

Plate dissipative silencers allow to reduce the noise that spreads in channels of large industrial facilities. One of the most important characteristics of these type silencers is aerodynamic drag. The use of variable-shape plates and wedge-shaped output fairings reduces that drag. To further improve the design of silencers is proposed to fill the output wedge-shaped fairing with sound-absorbing material. The article analyzes the acoustic and mass characteristics of plate dissipative silencers with wedge-shaped output fairings filled with sound-absorbing material. This paper presents the extra noise reduction for 9 octave bands (with center frequencies from 31.5 to 8000 Hz). Filling the output fairings allows to reduce the mass of the silencer up to 23%. Defined how changes the required length of 100–400 mm thick plates when filling the output fairings. Developed recommendations for constant and variable cross-section. A new method for analyzing the mass characteristics is discussed. Obtained the values of the specific masses of silencers. The universal dependence to choose thickness of the silencer's plates is received.