Partner: F. Scarpa

University of Bristol (GB)

Recent publications
1.Ahsani S., Claeys C., Zieliński T.G., Jankowski Ł., Scarpa F., Desmet W., Deckers E., Sound absorption enhancement in poro-elastic materials in the viscous regime using a mass–spring effect, JOURNAL OF SOUND AND VIBRATION, ISSN: 0022-460X, DOI: 10.1016/j.jsv.2021.116353, Vol.511, pp.116353-1-16, 2021
Abstract:

This paper investigates the mechanisms that can be used to enhance the absorption performance of poro-elastic materials in the viscous regime. It is shown that by adding small inclusions in a poro-elastic foam layer, a mass–spring effect can be introduced. If the poro-elastic material has relatively high viscous losses in the frequency range of interest, the mass–spring effect can enhance the sound absorption of the foam by introducing an additional mode in the frame and increasing its out-of-phase movement with respect to the fluid part. Moreover, different effects such as the trapped mode effect, the modified-mode effect, and the mass–spring effect are differentiated by decomposing the absorption coefficient in terms of the three energy dissipation mechanisms (viscous, thermal, and structural losses) in poro-elastic materials. The physical and geometrical parameters that can amplify or decrease the mass–spring effect are discussed. Additionally, the influence of the incidence angle on the mass–spring effect is evaluated and a discussion on tuning the inclusion to different target frequencies is given.

Keywords:

meta-poro-elastic material, Biot–Allard poroelastic model, mass–spring effect, viscous regime

Affiliations:
Ahsani S.-Katholieke Universiteit Leuven (BE)
Claeys C.-Katholieke Universiteit Leuven (BE)
Zieliński T.G.-IPPT PAN
Jankowski Ł.-IPPT PAN
Scarpa F.-University of Bristol (GB)
Desmet W.-Katholieke Universiteit Leuven (BE)
Deckers E.-Katholieke Universiteit Leuven (BE)