Tank bottom leak detection using AE: on the mechanism of the occurrence of AE bursts due to leakage

Abstract

During leak and bubble tests on a test tank, AE bursts are frequently detected along with the pressure change due to the unsteady flow close to the hole. A model, based on a postulated unsteady state and concentrating on the relationship between. the flow and the velocity gradient, is presented to explain the occurrence of AE burst. It is suggested that only the stream that is crossing the steep velocity gradient near the hole edge will produce strong AE bursts. An unsteady flow is considered favourable for such stream to occur therefore producing more AE bursts.