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						Ahsani S.♦, Boukadia R.F.♦, Droz C.♦, Zieliński T.G., Jankowski Ł., Claeys C.♦, Desmet W.♦, Deckers E.♦, On the potential of meta-poro-elastic systems with small mass inclusions to achieve broad band a near-perfect absorption coefficient,
						ISMA2020 / USD2020, International Conference on Noise and Vibration Engineering / International Conference on Uncertainty in Structural Dynamics, 2020-09-07/09-09, Leuven (BE), pp.2463-2472, 2020 Streszczenie: This paper discusses the potential of meta-poro-elastic systems with small mass inclusions to create broadband sound absorption performance under the quarter-wavelength limit. A first feasibility study is done to evaluate whether embedding small mass inclusions in specific types of foam can lead to near-perfect absorption at tuned frequencies. This paper includes an optimization routine to find the material properties that maximize the losses due to the mass inclusion such that a near-perfect/perfect absorption coefficient can be achieved at specified frequencies. The near-perfect absorption is due to the mass-spring effect, which leads to an increase in the viscous loss. Therefore, it is efficient in the viscous regime. The well-known critical frequency, which depends on the porosity and flow resistivity of the material, is commonly used as a criteria to distinguish the viscous regime from the inertial regime. However, for the types of foam of interest to this work, the value of critical frequency is below the mass-spring resonance frequency. Hence, the inverse quality factor is used to provides a more accurate estimation on the frequency at which the transition from the viscous regime to the inertial regime. Afiliacje autorów:
 | Ahsani S. |  -  | Katholieke Universiteit Leuven (BE) |  | Boukadia R.F. |  -  | inna afiliacja |  | Droz C. |  -  | inna afiliacja |  | Zieliński T.G. |  -  | IPPT PAN |  | Jankowski Ł. |  -  | IPPT PAN |  | Claeys C. |  -  | Katholieke Universiteit Leuven (BE) |  | Desmet W. |  -  | Katholieke Universiteit Leuven (BE) |  | Deckers E. |  -  | Katholieke Universiteit Leuven (BE) |  
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