Abstract: Due to the multi modes and dispersion nature of acoustic emission (AE) propagating in pipeline, traditional cross correlation technique do not perform well for acoustic leak location. Based on the theory of modal acoustic emission, the principle of guided waves in pipe is applied to AE leak location, and an acoustic leak model with dispersive multi-mode is developed. With the disperse characteristic of guided waves in pipe, an individual mode is isolated by the time-space analysis of the acoustic leak signals. Further more using the information of the individual mode a new leak location model is brought out. Leak location experiments are conducted to verify the validity of the location technique. It is indicated that the acoustic leak location model is practical and effective to locate the leak both of the liquid and gas.

Key words: Disperse, Guided waves, Leak location, Modal acoustic emission, Pipeline