Determination of acoustic emission source co-ordinates according to time difference in signal arrival to several receivers

Considered is determination of the coordinates for acoustic emission (AE) sources during nondestructive testing of NPP power reactors based on time difference in signal arrival (DTA) at several separated receivers. Variants of the receiver location are pointed out. It is shown that the more flexible location during AE-testing of large surfaces with complex configurations and high noise resistance are provided by four-point groups of the receivers-piezoaerials as compared to three-point ones. Described are the algorithm for calculating AE source coordinates at the four-point reception scheme and the zone method for determining AE source location. Carried out are evaluations of the errors of determining AE source location for four-point scheme and the error of acoustic field reflection caused by the final accuracy of TDA counts. Considered is the procedure of TDA pseudocombination sorting