Modelling Plate Silencers Elements for Large Industrial Facilities

Plate silencers are widely used in power engineering. When plate silencers are installed in ducts, not only their acoustic efficiency must be considered. Their usage leads to the increment of aerodynamic drag, which affects the characteristics of draft machines. Their own electricity consumption may increase and restrictions on their operation may appear. The main element of plate dissipative silencers is a plate filled with a sound-absorbing material. The characteristics of the plates and materials are well-studied and described. The article analyzes the influence of the presence and shape of the inlet and outlet fairings on the aerodynamic and acoustic characteristics of plate dissipative noise silencers. It also shows that the optimal shape of the inlet fairings is a half-cylinder. The authors recommend using wedge-shaped fairings as the outlet ones. The article explores the issue of the reflection of sound energy from the input end of the plate. The sound energy at the entrance to the silencer partially reflects back into the duct. With the help of the analytical method and mathematical modelling tools the authors have revealed that the shape of the inlet fairing doesn’t affect the amount of reflected energy