Microstructure based model for sound absorption predictions of perforated closed-cell metallic foams.
Closed-cell metallic foams are known for their rigidity, lightness, thermal conductivity as well as their low production cost compared to open-cell metallic foams. However, they are also poor sound absorbers. Similarly to a rigid solid, a method to enhance their sound absorption is to perforate them. This method has shown good preliminary results but has not yet been analyzed from a microstructure point of view. The objective of this work is to better understand how perforations interact with closed-cell foam microstructure and how it modifies the sound absorption of the foam. A simple two-dimensional microstructural model of the perforated closed-cell metallic foam is presented and numerically solved. A rough three-dimensional conversion of the two-dimensional results is proposed. The results obtained with the calculation method show that the perforated closed-cell foam behaves similarly to a perforated solid; however, its sound absorption is modulated by the foam microstructure, and most particularly by the diameters of both perforation and pore. A comparison with measurements demonstrates that the proposed calculation method yields realistic trends. Some design guides are also proposed.
Chevillotte
Fabien
F
GAUS, Department of Mechanical Engineering, Université de Sherbrooke, Quebec J1K 2R1, Canada. fabien.chevillotte@2006.ecam.fr
Perrot
Camille
C
Panneton
Raymond
R
D000042:Absorption; D000162:Acoustics / Q000295:instrumentation; D003198:Computer Simulation; D004867:Equipment Design; D020342:Finite Element Analysis; D008670:Metals; D008962:Models, Theoretical; D009622:Noise / Q000517:prevention & control; D009716:Numerical Analysis, Computer-Assisted; D016062:Porosity; D011312:Pressure; D013016:Sound; D013696:Temperature; D014783:Viscosity
D008670:Metals