This study presents a peridynamic (PD) constitutive model for visco-hyperelastic materials under homogenous deformation. The constitutive visco-hyperelastic model is developed in terms of Yeoh strain energy density function and Prony series. The material parameters in the model are identified by optimizing the classical stress–strain relation and tension test data for different strain rates. The peridynamic visco-hyperelastic force density function is proposed in terms of the peridynamic integral and the Yeoh strain energy density. The time-dependent behaviour for different strain rates is captured by numerical time integration representing the material parameters. The explicit form of peridynamic equation of motion is then constructed to analyse the deformation of visco-hyperelastic membranes. The numerical results concern the deformation and damage prediction for a polyurea membrane and membrane-type acoustic metamaterial with inclusions under homogenous loading. Different surface defects are considered in the simulation. The peridynamic predictions are verified by comparing with finite element analysis results.

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To enhance the low-frequency broadband sound absorption, we propose an absorber filled with porous material and establish a relative acoustic model. Based on the critical coupling condition, a Helmholtz absorber was designed to achieve perfect sound absorption at 172 Hz by the complex frequency plane method. Considering the weak adjustability and acoustic impedance of the Helmholtz absorber, we devised four absorber filled with porous material units that can achieve perfect sound absorption at discrete frequencies between 400 and 488 Hz with a thickness of only 51 mm. A composite absorber filled with porous material was designed by arranging four absorber filled with porous material units in a coplanar manner. The broadband perfect sound absorption of the composite absorber filled with porous material was subsequently verified by simulation and experiment. The thickness of the composite absorber filled with porous material is only 1/18 of the wavelength corresponding to the perfect absorption frequency, and it shows excellent subwavelength characteristics. The theoretical acoustic model of the composite absorber filled with porous material and the complex frequency plane method can achieve a more efficient design of broadband perfect sound absorbers. The composite absorber filled with porous material not only realizes low-frequency broadband perfect sound absorption but is also lightweight and easy to fabricate. This demonstrates the composite absorber filled with porous material structure has great potential for application in low to mid frequency noise control.

This study focuses on the constitutive model including temperature and pressure effects to investigate the dynamic, mechanical and acoustic properties of elastomers in frequency domain under different underwater conditions. The developed constitutive relation is based on Harvriliak-Negami (H-N) model by implementing experimental Young's modulus data and by using Williams-Landel-Ferry (WLF) shift function for relaxation time calculation. The H-N model accurately captures the dynamic mechanical modulus for wide range of frequencies for constant temperature and pressure based on measured DMTA (dynamic mechanical thermal analysis) data. Since the WLF shift function is related with the relaxation time for different temperatures and pressures, the proposed model represents a simple and accurate prediction of dynamic modulus for varying external conditions. Relationship between Young's modulus and acoustic properties of the rubber structure can be established by investigating the hydro-wave propagation process. The predictions from the proposed model are verified by comparing with mechanical and acoustic experimental data at different temperatures and pressures. Additionally, the parametric study is conducted to investigate the effect of H-N parameters on mechanical and acoustic properties of elastomer materials. The proposed model can be used to predict the mechanical and acoustic properties in different environmental conditions accurately.