Elias Zea

On modified wavenumber filters for rail contribution estimations

This brief communication exposes an overview of various wavenumber filters to separate the rail contribution to pass-by noise via the wave signature extraction method [Zea, Manzari, Squicciarini, Feng, Thompson, and Lopez Arteaga, J. Sound Vib. 409, 24-42 (2017)]. It has been found that the originally proposed filters underestimate the rail noise at frequencies above 1.6 kHz due to the presence of higher-order wave families that is unaccounted for. The goal of this letter is thus to propose and examine different filter functions that can capture such waves, and to assess whether the rail contribution estimations can be improved.

Single-layer array method to reconstruct extended sound sources facing a parallel reflector

The accuracy of sound field reconstruction methods with single-layer microphone arrays is subject to the room or enclosure in which the measurements take place. Thus, the authors recently introduced a single-layer method that can be employed to reconstruct compact sources in the presence of a reflecting surface that is parallel to the array. Now the authors propose a method conceived for extended planar sources such as baffled plates facing a parallel reflector. The method is based on a wavenumber-domain function describing the propagation paths between the source, the reflector and the array. The free-space sound field radiated by the source is then recovered by means of a regularized inversion of the propagation function. Numerical simulations are performed in order to assess the methods performance and potential for source reconstructions. The results are promising and point towards future experimental validation.