Optimization Method of Acoustic Filter Structures Composed of Helmholtz Resonators Based on Genetic Algorithm

Abstract

This paper constructs an iteration method based on Genetic Algorithm to optimize the acoustic filter structure comprising Helmholtz resonators, providing a new approach to optimize the low-frequency filtering performance of the acoustic structure under the constraint of keeping the resonator volume unchanged. First, acoustic-electrical analogy is used to design a fifth-order Chebyshev type II acoustic filter structure, which comprises two rectangular Helmholtz resonators; second, an iteration method is constructed based on Genetic Algorithm to optimize the shape of Helmholtz resonator under the constraint of keeping the resonator volume unchanged; finally, an optimal acoustic filter structure is obtained by implementing the iteration procedure to design shapes of the two Helmholtz resonators. The simulation results show that, compared with the original rectangular Helmholtz resonator, the optimal Helmholtz resonator has a reduction of about 10% in the resonant frequency and an obvious shift of the transmission loss curve towards low frequencies; the optimal acoustic filter structure has an effective attenuation frequency range of 84-232Hz, showing a significantly improved low-frequency filtering performance, verifying feasibility and effectiveness of the iteration optimization based on Genetic Algorithm.