Doctoral thesis focuses on the analysis of the coupled Helmholtz resonator in a liquid medium in the low-frequency range. The coupled vibroacoustic problem includes fluid-structure interaction and coupling of acoustic cavities. Based on the modal-interaction approach an analytical model is developed for the coupled system of an flexible Helmholtz resonator and an acoustic cavity. Improved representation of the pressure response at the geometric discontinuities is achieved with new formulation of the evanescent waves. Hydroelastic vibration of the elastic plate is included in the proposed model to account for the interaction between the structure and the free acoustic field. Furthermore, mechanisms of the acoustic losses and structural damping are implemented. For the purpose of the experimental validation, an impedance tube for the low-frequency dissipation measurements in the liquid medium is designed and methods for the identification of the sound velocity and attenuation are developed. The absorption coefficients of the test Helmholtz resonators show good agreement between the model and the measurements. The proposed model gives more accurate results than the FEM analysis.
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