Study On Acoustic Characteristics Of Enclosed Cavity-Helmholtz Resonators Coupling System

Enclosed cavity noise,represented by ship cabins,exists widely in real life.Helmholtz resonator has been usually used on account of its simple structure and favorable sound absorption characteristics.A deep understanding of the coupling mechanism of the two is the basis for the effective noise elimination and is conducive to the further implementation and optimization of the muffling scheme.Therefore,the following work is carried out in this paper for the enclosed cavity-Helmholtz resonators coupling system:The energy method is employed for the description of the enclosed cavity-Helmholtz resonators coupling model.A three-dimensional improved Fourier series is constructed to express the sound pressure function,combining the Rayleigh-Ritz procedure to get the matrix formula of the system governing equation.Finally,all the eigenvalues and eigenvectors of the acoustic properties can be obtained by the eigenvalue decomposition.Then the numerical examples show the feasibility of the present model,and the influence of acoustic characteristics in the cavity after introducing the Helmholtz resonators is studied.The reliability of the proposed model is verified by good consistency with the response prediction of other methods in the literature.On the basis of validation of the theoretical model,the influence of the position and impendence of Helmholtz resonator on the noise reduction performance and the cavity modal decay time is studied.Finally,the acoustic experiment of the enclosed cavity-Helmholtz resonators coupling system is designed.The experimental results are compared with the simulation ones,which proves the correctness of the present method and the accuracy of programming.Above all,it is verified that the design scheme of Helmholtz resonators has its application references.