Coupled Helmholtz resonators for broadband Aeroacoustic noise mitigation

As a structurally simple acoustic element, Helmholtz resonators can exhibit strong resonance when acoustic waves enter the cavity, thus providing excellent sound absorption effects. Consequently, they are widely applied in automotive engine and exhaust systems. This paper systematically investigates the noise reduction performance of multiple coupled Helmholtz resonators under conditions with and without tangential flow. A finite element simulation model with multiple Helmholtz resonators is established by employing COMSOL Multiphysics software to solve the linearized Navier-Stokes equations in the frequency domain. The simulation results demonstrate that the structure, which couples multiple Helmholtz resonators, can effectively broaden the low-frequency sound absorption band under the influence of a flow field, enhancing the transmission loss across the entire low-frequency band. This structure holds significant potential for applications in automotive exhaust systems and aero-engine noise reduction.