Mechanical Parameters Effects on Acoustic Absorption at Polymer Foam

Abstract

Polymer foams have acoustic absorption properties that play an important role in reducing noise level. When the skeleton is set to motion, it is necessary to use generalized Biot-Allard model which takes into account the deformation of the skeleton and the fluid and the interactions between them. The aim of this work is to study the quality of acoustic absorption in polyurethane foam and to show the importance of the structural vibration of this foam on the absorption by varying mechanical parameters (Young’s modulusE, Poisson’s coefficientν, structural damping factorη, and the densityρ1). We calculated the absorption coefficient analytically using classical Biot formulation (us,uf) and numerically using Biot mixed formulation (us,p) in 3D COMSOL Multiphysics. The obtained results are compared together and show an excellent agreement. Afterwards, we studied the effect of varying each mechanical parameter independently on the absorption in interval of ±20%. The simulations show that these parameters have an influence on the sound absorption around the resonance frequencyfr.

Investigation on Compression Mechanical Properties of Rigid Polyurethane Foam Treated under Random Vibration Condition: An Experimental and Numerical Simulation Study

“…However, beyond that, polyurethane foam also was often used as core material to make sandwich board [22,23] and honeycomb board structures [24], because of its good vibration absorption and isolation performance. To understand the vibration characteristics of foam materials, the researchers studied the density, strength, and viscoelasticity of foam materials [25,26]. Lyes Dib et al found through the 3D COMSOL Multiphysics that Young’s modulus, Poisson’s ratio, damping factor, and density of polyurethane foam would change the absorption coefficient, thereby affecting the sound absorption performance [25].…”

“…To understand the vibration characteristics of foam materials, the researchers studied the density, strength, and viscoelasticity of foam materials [25,26]. Lyes Dib et al found through the 3D COMSOL Multiphysics that Young’s modulus, Poisson’s ratio, damping factor, and density of polyurethane foam would change the absorption coefficient, thereby affecting the sound absorption performance [25]. The method of finite element numerical simulation could be used to analyze the material properties of foam materials under the vibration environment.…”

Vibration Damping and Acoustic Behavior of PU-Filled Non-Stochastic Aluminum Cellular Solids

“…If, during the acoustic propagation, the structure can no longer be considered rigid, for instance, in the case of the polyurethane foams that are used to infiltrate the samples, the formulation must be corrected [43]. According to the poroelastic Biot's theory [46,47], the surface impedance (Z) may be calculated using Equations ( 15) and ( 16) [48]:…”

“…The referred theory considers that the propagation by compression waves is due to three separate waves: fast (P 1 ) and slower (P 2 ) compression waves and a shear wave (S) [48]. Considering these facts, the surface impedance (Z) may be divided into four possible impedance combinations according to Equations ( 17) and (18).…”

Computational Investigations on Soundproof Applications of Foam-Formed Cellulose Materials

“…In addition, mechanical characterizations of the poroelastic materials (i.e., polyurethane foam, recycled rubber, polyurethane resin, etc.) have been comprehensivly analyzed [25,26,27,28]. The reference papers show the importance of structural vibration in polyurethane foam, as the characteristic impedance and propagation of constant absorption vary the mechanical parameters like density, Young’s modulus, Poisson’s coefficient, and the structural damping factor, all characteristics that have influence on resonance frequency absorption.…”