Fundamental guided wave attenuations and sensor location estimation in fluid-filled steel pipes

The sound intensities required to sustain a certain interval between two ultrasonic sensors that are installed outside a steep pipe for structural health monitoring are numerically investigated. Two fundamental guided wave modes, longitudinal and flexural, are considered for the calculation of their attenuations via the concept of parametric density and a sink inside steel pipes, and these attenuations are used for the sound-intensity calculations. The results, attenuations, and sound intensities are useful as a guideline when guided-ultrasonic-wave-based inspection is planned for pipeline maintenance and safety, especially for estimation of the axial location between ultrasonic sensors.