Numerical Validation of a Time Domain Perforated Plate Model with Nonlinear and Inertial Effects

Artikel i vetenskaplig tidskrift, 2014

A time domain perforated plate model based on the "homogenization" concept is presented; the dynamic porous wall model. This model takes into account linear and nonlinear losses as well as inertial effects due to the unsteady flow in the vicinity of the holes. A numerical validation of the dynamic porous wall model is performed via the computation of the impedance versus frequency for an acoustic liner consisting of a solid wall back sheet and a perforated face sheet, separated by a given distance. Two types of unsteady flow are considered; firstly 3D LES in which the holes in the perforated face sheet are fully resolved, and secondly 2D URANS simulations in which the dynamic porous wall model is used to include the effects of the perforated face sheet. Comparisons of the results show that the new dynamic porous wall model captures both nonlinear and inertial effects well.