Thermal and Acoustic Numerical Simulation of Foams for Constructions

Cellular foams are widely employed as insulation materials, both thermal and acoustic, often in competition with traditional fibrous insulation material, e.g., rock wool. As for the acoustic and thermal properties, several models have been developed to predict acoustic properties of poroelastic materials, but they are usually applied to fibrous layers or polyurethane foams, whereas their application to new materials like complex cellular foams has not been assessed due to the different cell microstructures. There is a very strong interest both in industrial and academic in developing novel insulation materials; accordingly, the possibility of ideally designing the cellular foam microstructure to achieve desired acoustic performances appears a highly attractive target. The paper will first discuss the state-of-the-art acoustic and thermal models and their application to cellular foam materials. Then a novel sustainable alginate-based foam material will be analyzed as a case study, by focusing the aspects related to their microstructure and acoustic properties. For the derivation of an acoustic model, the determination of the parameters of JohnsonChampoux-Allard (JCA) acoustic model (tortuosity, viscous characteristic length, thermal characteristic length, porosity, and flow resistivity) was performed using five different forecasting methods, including traditional analytical model for fibrous materials as well as inverse procedure.