Series of split silencers for ventilation systems

Abstract

Abstract The paper is devoted to the prospects of noise reduction in ventilation systems with large cross-section main air ducts. The design schemes of a split silencer for various systems obtained as a result of calculations and experiments are proposed. For a silencer whose split ducts are formed by successive narrowings and expansions the parameters ensuring minimum noise reduction of 7.5 dB and pressure loss of up to 120 Pa are shown and the recommendations for usage in systems where two-phase flows propagate are given. For a silencer whose split ducts contain internal elements the parameters that provide a minimum noise reduction of 10 dB and pressure loss of up to 90 Pa are identified and the recommendation for usage in supply ventilation systems with the required disinfection is presented. For a silencer that combines two sections with oppositely oriented split ducts its applicability in systems without aerodynamic restrictions and with increased acoustic requirements was noted. For additional silencer section composed from Helmholtz split resonators the parameters that ensure even noise reduction are shown and the recommendation for usage in systems without restrictions on the length of the main duct and with increased low-frequency noise reducing requirements is given.