Composing the Reactive Silencer for Engineering Networks

Abstract

Abstract The substantiation of using reactive silencers in flues and air ducts with two-phase flows is given. It is noted that a silencer on main duct is the multimode system, which ability to even noise reduction in wide frequency range is not enough fully investigated. Reactive silencer’s scheme as a duct separated by bent partitions into range series of reflecting elements that are single-mode in one direction and multimode in the other direction is presented. It is indicated that the implementation options of the proposed scheme were calculated by methods of electroacoustic analogy and were tested on a model stand with flows. The conditions achieving even noise reduction in wide range of frequencies with acceptable aerodynamic resistance were determined: expansion degree in silencer extreme series is 2.5, expansion degree in remaining series is 4; indicator of change lengths for pairwise equal narrowing and extension sections is 2−0.6. The scheme containing expansion chambers, resonator chambers, sections with oppositely oriented partitions was clarified on the device effectiveness in various engineering networks. Obtained results show that for reactive silencers with bent partitions scheme parameters ensuring the required throughout the normalized frequency range with acceptable aerodynamic resistance have been established