Estimation of the Acoustic Reflection Characteristics of a Plane Surface Having aPeriodic, Spatially-Varying Surface Admittance

摘要

A possible technique for studying the acoustic reflection from continuous planesurfaces such as flat plates covered with thin anechoic coatings is discussed. It is particularly directed to complex coatings which include a regular array of non-homogeneous inclusions within their structures. The method involves the experimental determination of a position-dependent quantity which can be viewed as either a surface transfer admittance or a surface transfer mobility function. This function can then be used in a mathematical convolution procedure to determine the nature of the reflected wave from surface when it is ensonified by an incident uniform plane wave arriving in a direction normal to the plate surface. The basic elements of an experimental system for measuring the surface admittance function are discussed.