Locating an Acoustic Emission Source in Multilayered Media Based on the Refraction Path Method

The traditional acoustic emission (AE) source location method, which is based on the model of a single-layered medium, is not appropriate for accurately locating AE sources in multilayered media. To solve this problem, an innovative AE source location method based on a refraction path (RP) method is proposed. In this new method, the refraction points at each interface are first solved according to Snell's law and then substituted into the equations for the time difference of arrival (TDOA). Second, linear equations can be obtained by linearizing the TDOA equations. Finally, the optimal AE source can be obtained by iteratively updating the trial solution based on the linearized equations. The results of a pencil-lead break experiment and a numerical simulation show that the proposed method is applicable of locating the actual AE source in both the single- and multilayered media, and the location error of this method in multilayered media is significantly smaller than that of the traditional method.