Hydroacoustic Rupture-Detection System for Major Underwater Pipelines

Abstract

In modern conditions, a continuous monitoring system for major underwater pipelines is an essential part for maintenance of their normal operating. One of the possible approaches to the development of a continuous control system for the pipeline technical condition can be the method that is based on the luminal echo sounding. The work contains numerical experiments for the analysis of influence of leaks and ruptures of gas pipelines on the structure of the illuminated acoustic fields in conditions of natural stochasity of water environment. In the quantitative experiment, the emitter was located on the axis of underwater acoustic channel (UAC). In this case, all the acoustic energy spreads along the UAC axis and there are no shade zones. As a result of the numeric experiments, correlations between the acoustic field distribution along the axis of underwater acoustic channel with and without gas pipeline ruptures at the range of 1 km and different levels of the random componentry were obtained. In the numeric experiment, the random componentry of the acoustic velocity field was discretely changing from 0,05 m/s to 0,5 m/s. The pipeline rupture was modelled at the ranges of 35; 70; 100 km. Pipeline rupture shifts the UAC axis; consequently, the acoustic field range rapidly drops at the depth of emitter. This effect is observed at all levels of the random componentry of the acoustic velocity field in the numeric experiments. Hydroacoustic leak-detection system for major gas pipelines is suggested based on the obtained results; it consists of the emitter and discrete receivers located along the UAC axis. The allocation precision is determined by the intervals between receiver along the UAC axis.