Analytical and experimental methods for the non-destructive acoustic testing of fluid-filled critical infrastructure from the 19th century to the present

Abstract

From boreholes and chimneys, to pipelines, boilers, storage tanks, reactors, and water mains, non-destructive acoustic tests of fluid-filled conduits and shells help to monitor vital infrastructure across the globe. The theoretical treatment of wave propagation in such structures has its origin in the 19th century. In the intervening years, advances in sensors, data logging, and signal processing led to practical applications, first in oil exploration and later in other fields such as medicine and water distribution. This commercial activity accelerated the understanding of wave propagation in large scale multi-layered and multimaterial structures to create a host of new commercial applications. The paper explores the evolution and current state of these technologies and the acoustics behind them through an historical study of the progression of conduit wall impedance modeling and the problems of reflection and dispersion, as encountered in borehole and pipe inspection applications.