Improvements to the Two-Thickness Method for Deriving Acoustic Properties of Materials

摘要

The Newton-Raphson and Wave Number Space methods of finding solutions for thernpropagation constant when given specific impedance data derived from samples of differentrnthicknesses are shown to produce results comparable to the two-thickness method. The two newrnapproaches do not require that the sample thicknesses be a ratio of 2, thus allowing morernanalyses to be performed on available sample data. Understanding regions of valid datarnimproves interpretation of results and provides a means of combining the valid regions of resultsrnassociated with data from different sample thicknesses.